text:
In December 1941 Japan declared war on Britain and the United States of America. Japan had already been at war with China since 1931 and had forces positioned in the Far East ready to attack. Lightning strikes were made against such targets as Pearl Harbour, Hong Kong and Malaya. Soon after the British suffered a humiliating defeat in Burma and had to retreat westwards into India.
In January 1942, when the Japanese invaded Burma, the British War Office offered the services of Lieutenant-Colonel Orde Wingate DSO, to General Archibald Wavell, the then Commander-in-Chief of Allied forces in India. It was thought that there would be a role for Wingate in Burma with his proven guerrilla expertise, having previously carried out such operations operations in Palestine and Abyssinia with great success.
When Wingate arrived in March 1942 he was tasked with organising these guerrilla operations. He then began to investigate the job at hand and this was when he met Major Michael Calvert, who later became one of Wingate's most trusted and successful Chindit commanders. Together they carried out a reconnaissance of the terrain of north Burma.
Long Range Penetration Theory
Wingate (pictured left) then put forward his theory that formations of troops supplied from the air could operate for long periods in the jungle. The troops would be organised into columns, each large enough to inflict a heavy blow on the enemy but small enough to evade action if outnumbered. The columns would march into enemy territory to disrupt the Japanese Army's communications and supply chain and to generally create havoc behind its lines.
Wingate called this Long Range Penetration.
77th Indian Infantry Brigade (Chindits)
The Long Range Penetration theory was approved and Wingate's experimental force was formed and became 77th Indian Infantry Brigade.
The Brigade was made up of:
13th Battalion The King's (Liverpool) Regiment
3/2nd Gurkha Rifles
142 Commando Company
2nd Burma Rifles
Eight RAF Air liaison sections
Brigade Signal Section from The Royal Corp of Signals
A mule transport company.
The brigade now had to prepare themselves for two enemies, the jungle and the Japanese. Wingate did this by training them in the jungles of the Central Provinces of India, at places like Patharia and Saugor near Jhansi. The men prepared for column and bivouac life, learning to live off the land, train for jungle warfare, river crossings and the care of their beloved mules.
The mules were vital to the Chindit operation as they carried the heavy weapons, ammunition, radios and medical supplies. In Burma supply drops to the Chindits would also include fodder for the mules.
It was during this training period that Wingate chose the name Chindits for the force. It was a mispronunciation of the Burmese word Chinthe (a mythical creature that stands guard outside Burmese pagodas). It is said that Captain Aung Thin of the Burma Rifles was the originator of the name, suggesting that the half griffin, half lion creature symbolised the nature of the Chindits task in Burma that year.
Operation Longcloth
The original plan was that the Long Range Penetration group would be part of a three phased offensive into northern Burma in 1943, but this offensive was cancelled. Wingate then proposed that the Long Range Penetration operation should proceed alone, to test his theories and gain vital experience in the jungles of Burma.
General Wavell (seen left with Wingate in India in early 1943) agreed to this and the Chindits were ordered into Burma. The campaign was given the code name Operation Longcloth.
Wavell had hoped that the Wingate force would be the catalyst for a link up between Stilwell's group in the north, IV Corps in the west and Chiang Kai-Shek's Chinese Army in the east. As time moved on and the Chinese leader procrastinated it seemed inevitable that the plan was doomed to failure and should be cancelled.
On the 6th February Wavell arrived at Imphal to speak with Wingate. A long discussion took place that afternoon between the two men in the company of a third interested party, General Somervell of the United States Army.
Wavell explained:
"I had to balance the inevitable losses—the larger since there would be no other operations to divide the enemy's forces—to be sustained without strategical profit, against the experience to be gained of Wingate's new method and organization. I had little doubt in my own mind of the proper course, but I had to satisfy myself that the enterprise had a good chance of success and would not be a senseless sacrifice: and I went into Wingate's proposals in some detail before giving the sanction to proceed for which he and his brigade were so anxious."
Wavell then turned to General Somervell and asked for his view on the decision, the General answered:
"Well, I guess I'd let them roll."
And so the die was cast.
Column Organisation
Wingate organised his force into two groups.
1. Northern Group, consisting of columns 3,4,5,7,8 and Brigade HQ, totalling 2,000 men and 850 mules.
2. Southern Group, consisting of columns 1, 2 and group HQ, totalling 1,000 men and 250 mules.
(the fit men of no. 6 column were broken up and dispersed into the other column units to replace the sick and wounded from the arduous training).
Attached to each column was a RAF Air Liaison section.
A rear HQ remained behind to organise the air supplies for the columns, this was led by Captain Horace Lord.
Each column was typically composed of:
about 400 men built around an infantry company
a reconnaissance platoon of the Burma Rifles
a Commando platoon
two mortar and two Vickers machine guns teams
a mule transport platoon (about 120 mules)
RAF liaison officer and radio operators to direct air supplies
a radio detachment to provide communications between columns.
Each column would march independently and be supplied by air. Where necessary columns would concentrate to achieve specific tasks.
Wingate's aim for this type of column organisation was to achieve mobility and security. Without having to rely on road-based transport and land based communications lines, a column could go anywhere it wished. These mobile units would then disappear back into the jungle screen making it almost impossible for the Japanese to find them and thereby providing the security it required to operate successfully.
Below is the Operational Order of Battle for Longcloth, showing the breakdown of Units and Columns and their respective Commanders.
Operation Longcloth, Order of Battle 1943.
Below is a copy of a listing I came across in one of the many file documents concerning the operation in 1943. It shows the final numbers in regards to personnel of each of the columns and Group head quarters as the Brigade entered Burma in February that year. It shows us the small number of Column 6 soldiers still available just before they were disbanded and re-distributed amongst the other British units. The title groupings are self explanatory apart from perhaps the ambiguous heading of 'Others'. This, I believe, refers to the mainly Indian orderlies, cooks and camp followers that helped make up the numbers of 77th Indian Infantry Brigade. This is the only time I have seen such a precise document in terms of company numbers and I think it makes for very interesting reading.
Air Supplies
Air supply was provided by a detachment from 31 Squadron of the RAF and operated from Agartala in eastern Bengal. It varied in size during the expedition but seldom exceeded three Hudson and three DC3 aircrafts. Fighter escorts were provided when the range permitted but were not available when emergency drops had to be made at short notice. No aircraft was lost during the operation. The Chindits selected the drop zones when and where required. Initially it was thought that airdrops would only succeed in open clearings, but by chance an emergency airdrop had to be made in jungle terrain, this proved successful and this method was to be used again. Even though the airdrops themselves were successful, the difficulty of the operation meant that on average each man only received half of the rations they required.
NB. Column 5 only received a mere 20 full days rations during the 80 days it spent in Burma that year.
The photo pictured above is a typical preparation for a supply drop, with 'kicker's out' ready to push the required Chindit stores out from the aircraft to the hungry men below.
Into Burma
On the 8th February 1943 the Chindits commenced their advance into Burma from Indian base town of Imphal.
Wingate issued his Order of the Day as the Chindit Columns commenced their crossing of the Chindwin River on 13th February:
Today we stand on the threshold of battle. The time of preparation is over, and we are moving on the enemy to prove ourselves and our methods. At this moment we stand beside the soldiers of the United Nations in the front line trenches throughout the world. It is always a minority that occupies the front line. It is still a smaller minority that accepts with a good heart tasks like this that we have chosen to carry out. We need not, therefore, as we go forward into the conflict, suspect ourselves of selfish or interested motives. We have all had opportunity of withdrawing and we are here because we have chosen to be here; that is, we have chosen to bear the burden and heat of the day. Men who make this choice are above the average in courage. We need therefore have no fear for the staunchness and guts of our comrades.
The motive which has led each and all of us to devote ourselves to what lies ahead cannot conceivably have been a bad motive. Comfort and security are not sacrificed voluntarily for the sake of others by ill-disposed people. Our motive, therefore, may be taken to be the desire to serve our day and generation in the way that seems nearest to our hand. The battle is not always to the strong nor the race to the swift. Victory in war cannot be counted upon, but what can be counted upon is that we shall go forward determined to do what we can to bring this war to the end which we believe best for our friends and comrades in arms, without boastfulness or forgetting our duty, resolved to do the right so far as we can see the right.
Our aim is to make possible a government of the world in which all men can live at peace and with equal opportunity of service.
Finally, knowing the vanity of man's effort and the confusion of his purpose, let us pray that God may accept our services and direct our endeavours, so that when we shall have done all we shall see the fruit of our labours and be satisfied.
O.C. Wingate, Commander,
77th Indian Infantry Brigade.
Initially the columns met no opposition, but soon some of the units were sighted by the Japanese, who initially believed them to be small groups gathering intelligence. It was not until there had been a number of engagements with Japanese outposts and patrols and the successful demolition of railway bridges, that the enemy realised the force opposing them was of Brigade strength. The Japanese had been caught by surprise and were confused, not knowing the intention of the Chindits or how they were supplied. Three regiments, each of three battalions, were sent to the area to locate and destroy the invaders. The Chindits now became the hunted.
The Japanese were not aware that the Chindits were being supplied by air and so sent troops westward hoping to cut their land supply routes. On 13th March an airdrop was interrupted and had to be aborted, due to Japanese interference. The Japanese at last realised that the Chindits were being supplied from the air and the enemy troops searching for traditional supply lines were brought back to intensify the hunt for the elusive intruders.
By now the Chindits were deep in enemy territory. Withdrawal would be hazardous as the return route to India required the re-crossing of two major rivers (Irrawaddy and Chindwin), which would now be guarded by the Japanese. Despite this, the Chindits continued their advance eastwards attacking targets as they went.
Pictured below is the Gokteik viaduct in 1945, this was the most southeasterly target considered for destruction on operation Longcloth. Mike Calvert's column 3 were on their way there, when the order came through to return home to India. Frustratingly, this was the second time he had just missed out on destroying the structure, having failed to complete the task the year before on his mischievous retreat out of Burma.
The Gokteik Viaduct.
On 24th March Wingate was ordered to withdraw. By then the Chindits had advanced so far to the east that they were almost out of range for air supply. They also found themselves in an area short of water and heavily patrolled by the Japanese, exhaustion and hunger began to take it's toll. The Japanese had now committed a large force in an attempt to surround and capture the Chindits.
Wingate gave the order to disperse into smaller groups. Non-essential equipment was dumped and mules no longer required were turned loose. By now the Chindits were tired and very short of food, many were wounded or sick, now they faced an arduous journey home pursued by a determined enemy. Many of them would not make it back to India.
One column (seven) made their way out toward China, another (eight) built an airstrip in jungle clearings and evacuated the sick and wounded by air, the rest returned by re-crossing the Irrawaddy and Chindwin Rivers either as a column unit or split into smaller dispersal groups to avoid the Japanese net.
Of the 3,000 officers and men that went into Burma in 1943, only 2,182 came back four months later, having covered between 1,000 and 1,500 miles deep in enemy held territory. They were in poor condition, suffering from tropical diseases and malnutrition but in high spirits and proud of their achievements. Of those that returned only about 600 were passed fit for further active service.
Achievements and Lessons Learned
The Chindits had entered northern Burma, caused some damage to the railway and inflicted minor casualties on the enemy. They had shown that it was possible to infiltrate and operate in difficult jungle terrain deep within enemy held territory.
Wingate had proved his theory of Long Range Penetration could work and that Allied troops could raid effectively behind enemy lines. The use of new styled radio communication and most importantly of all the success of the air supply system were valuable plus points during the 1943 expedition.
The Japanese admitted afterwards that the Chindits had been difficult to deal with and had disrupted their plans to rest their troops in preparation for the invasion of Assam and the battles for Imphal and Kohima. The Mandalay-Myitkyina railway was put out of action for a few weeks forcing the Japanese to use longer and more limiting lines of communications. Between six and eight Japanese battalions had been diverted from other planned operations in order to eradicate the Chindit nuisance.
The Chindits were the first troops to fight back after the defeat in Burma and the operation showed that British troops could take on the Japanese and win. The Japanese had been thought to be invincible jungle fighters, the Chindits proved that this was not so. The legend of the Japanese superman was dealt a savage blow. This had a tremendous effect on the morale of troops in India and the population back home in Britain.
There were problems with the care of the sick and wounded, many had to be abandoned or left in so called friendly Burmese villages. This above all else had caused great consternation amongst the men on the operation, distraught at having to leave behind good friends and brave comrades, when they could no longer march or keep up with the group. As a result, the ability to evacuate sick and wounded became high priority for future missions.
Churchill had been so impressed with the operation that he, along with other Allied leaders, agreed to Wingate's plans to launch another Chindit expedition the following year. This would be on a much larger scale, this time consisting of six Long Range Penetration brigades. This second expedition returned to northern Burma in March 1944. Most of the men in this force would have the luxury of being flown into Burma instead of marching and landed in areas deemed suitable for purpose by reconnaissance from the year before.
Many thanks to Frank Young for allowing me to reproduce his overview and background to Operation Longcloth, taken from his brilliant website 'Chindits, Special Force, Burma 1942-44.'
Below is a typical Chindit dispersal group preparing to move out after a halt. This is almost certainly from the 1944 operation and I cannot recall the source for the photograph, so apologies to whoever that might have been.
Copyright © Steve Fogden, 2011.


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text:
Old Spice Classic
mps2341	Uncategorized	 November 23, 2010 5 Minutes
Hopefully GR2 brings his running shoes to the Notre Dame game
The Georgia Bulldogs are 3-0 for the first time since the 2007-2008 season, or as some people call it, "The season that ended with a tornado ripping through Atlanta, forcing the SEC Tournament into Georgia Tech's gym and resulting in the Dawgs winning the championship and earning an automatic bid to the NCAA Tournament".
But this 3-0 start has been far more impressive because the Dawgs are doing it without the SEC Preseason Player of the Year, Trey Thompkins.
And yes, Trey is listed as "doubtful" for this Thursday's game against Notre Dame in the first round of the Old Spice Classic in Orlando, Florida.
Yet, ESPN analyst Andy Katz (my favorite ESPN analyst of all-time) is sticking with Georgia to win this holiday tournament. Matter of fact, so are two of Katz's colleagues – Jay Williams and Fran Fraschilla.
It's too bad that Georgia didn't get that same kind of love in either of this week's national polls – Georgia remained unranked in both the AP (receiving 28 votes) and the ESPN/USA Today Coaches Poll (receiving 1 vote). The head-scratcher here is that in last week's polls, the Dawgs were receiving 42 votes in the AP and 4 votes in the Coaches – so they are being punished for winning without their best player?
Luckily for Georgia, the college basketball polls aren't nearly as significant as the college football polls – but it would be nice to crack one of those Top 25's since it hasn't happened in nearly seven years.
The best thing that the Dawgs can do his head down to Orlando and win some ball games.
And that starts with the Notre Dame Fighting Irish (3-0).
The Irish finished 23-12 last year (their 5th straight 20-win season) with a 10-8 record in Big East play. However, they did suffer two key losses from that roster – PF Luke Harangody, the team's leading scorer (21.8 ppg) and rebounder (9.1 rpg) and PG Tory Jackson who led the team with 5.3 assists and also chipped in 9.6 ppg.
Heading into this season, analysts felt that Notre Dame had enough depth in the frontcourt to replace Harangody's points and rebounds. The big concern for the Irish was in their backcourt, where they would be breaking in a new point guard.
Through the first three games, Notre Dame freshman point guard Eric Atkins has put a lot of those concerns to rest. Atkins, a McDonald's All-American nominee, has played well for coach Mike Brey, averaging 10.3 ppg, dishing out 4 assists/game and shooting a blistering 62.5% from beyond the three-point line.
Joining Atkins in the backcourt is senior guard Ben Hansbrough, the younger brother of Tyler "Psycho T" Hansbrough. Young Ben has been lighting it up from beyond the arc, hitting 15 of 25 three-point attempts (60%) and leading this team in both scoring (20.3 ppg) and assists (4.7).
The Notre Dame frontcourt is made up of three seniors and anchored by 6'8″ Tim Abromaitas, who had a "breakout season" last year, averaging 16.1 ppg and shooting 42.9% from three-point range. Abromaitas is out to a strong start this season, scoring 14.7 ppg and grabbing 7.3 boards despite hitting only 4 of 24 from beyond the arc (let's hope he doesn't find his touch against Georgia). He is a nightmare match-up for opposing bigs because he has the ability to score both inside and out – Price and Barnes are going to have their work cut out for them.
Tyrone Nash (11.3ppg / 7.0 rpg) and Carleton Scott (9.0 ppg / 8.0 rpg) round out the rest of the Irish frontcourt.
Senior wingman 6'8″ Scott Martin – a transfer from Purdue – gives Coach Brey a quality sixth man he can look to for a little bit of everything (6.5ppg, 4.0 rpg, 2.5 apg) off the bench.
Even though Notre Dame is 3-0, it's hard to judge just how good they really are because their schedule thus far has resembled "Cupcake Row" – Georgia Southern, Liberty and Chicago State. The Dawgs will no doubt be the first real test of the season for this Irish team.
However, Notre Dame will be the best team that Georgia has played so far as well – four seniors in the starting five, balanced scoring and rebounding and a proven coach in Mike Brey (the Irish have made it to the postseason in each of Brey's 10 seasons).
Georgia's last-second win at Saint Louis was definitely a great confidence booster for a team that didn't win a road game last season (I was at a family trip in Dahlonega, GA and unfortunately unable to listen – I did follow fervently on my phone under the dinner table and nearly kicked the person across the table from me when I refreshed the screen and saw 61-59).
But this team must clean up the turnovers (17 @ Saint Louis and 18 vs Colorado). Gerald Robinson, Jr. (GR2) had 8 assists at Saint Louis – including the dish to Jeremy Price that led to the game-winning bucket – but he nearly matched that total with 7 turnovers. If Georgia is going to find success down in Orlando, Coach Fox is going to need smarter play out of GR2, who has been the Dawgs' most pleasant surprise of this young season – 16.7 ppg and a team-leading 5.7 apg.
This is a senior-laden Notre Dame team that is only turning the ball over 10 times a game, meaning that they play smart with the ball and don't give their opponents too many extra possessions.
This game is going to present quite a rebounding challenge for the Dawgs' frontcourt of Price, Travis Leslie (G/F) and Chris Barnes. The Irish are grabbing 49 boards a game to Georgia's 34, and on top of that they have a serious size advantage inside – their roster is full of 6'8″ and 6'9″ bigs.
Barnes was productive again off the bench for Coach Fox against Saint Louis, hauling down 5 rebounds in just 14 minutes of play. He's averaging 7.0 rebounds in the last two games and needs to continue to attack the glass going forward with Thompkins on the sidelines.
Notre Dame will most likely be looking to slow the pace of this game down, allowing them to pound the ball inside on the Dawgs defensively. It will be up to GR2, Travis Leslie and Dustin Ware to push the ball and try to turn this game into a bit of a track meet because the Dawgs certainly have a quickness advantage.
I think the key to this game is going to lie in the hands (or legs) of Travis Leslie. Leslie has been sensational for Coach Fox so far this season, leading the team in points (18.0), rebounds (8.3) and minutes (32.0).
However, it's not just his offense that the Dawgs will rely on Thursday night – they are going to need a great defensive effort from Leslie as well. I am assuming that the 6'7″ Connor Nolte will match up with one of Notre Dame's bigs (maybe Carleton Scott?) because they have so much height inside (6'8″, 6'8″ and 6'7″).
This will leave Leslie to guard the Irish's leading scorer, Ben Hansbrough. Hansbrough is an excellent shooter, and guarding excellent shooters is difficult. Leslie will have to be aware of where "Psycho B" is on the court at all times, which will be a tiring endeavor.
The Old Spice Classic presents another great opportunity for this Georgia team to continue building its NCAA tournament resume. Any wins that the Dawgs can secure away from The Steg will go a long way in convincing tournament committee members that they deserve a bid in March (especially if they can continue to win without Trey).
The game will be televised at 7:00PM EST on ESPN2, meaning that this game (and tournament) will give Georgia some much-needed national exposure. Sounds like a nice thing to mention to recruiting prospects as well, doesn't it?
Hopefully the Dawgs can make playing in a preseason tournament a regular occurrence in the future. Winning a few games at the Old Spice Classic would certainly help.
Fran Fraschilla
Luke Harangody
Mike Brey
Travis Leslie
Trey Thompkins
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12 thoughts on "Old Spice Classic"
Decatur Dawg says:
CMF tweeted that Trey practiced today so we may see him in Orlando after all.
GO DAWGS – bring home that deodorant stick!
Sam B says:
If CMF posted that, it isn't on his twitter any more.
Hoop Dawg says:
CMF said Trey did more at practice, but it didn't sound like he expected him to play in Orlando
MarkS says:
I'd think it'd take a miracle for Trey to play in Orlando. Dawgs are playing game enough without him for now, so why risk rushing him back?
That said, I obviously wish we did have him. I think we're in for a tough game tomorrow. . .
All I can say is that I hope Trey is really sound before he makes an appearance. All games are important, but the holiday tilts are less so than the SEC games in January. I'd just as soon Trey sit out this week and maybe be ready for the UAB game on the 3rd. I also suspect that conditioning issues will limit him to about half-time duty (20 minutes or so) for the first 2-3 games back. Yet, even those will be very welcome minutes.
I wonder how long it will take him to get back up to speed?
I'd sort of gotten the feeling that he'd be out until the cupcake portion of our non-con schedule. Hope I'm wrong!
macdaddy says:
I think with Trey out, our realistic expectations of winning this tourney are about shot, If we could beat the suck Irish and somehow win 2 out of 3 this weekend, I would consider that a huge success. I am ready for some national stage UGA basketbal though, the luck of the Irish is about to run out tomorrow night. Go Dawgs!
Notre Dame is a 6.5 point favorite! I can't believe Vegas thinks the Irish are going to handle the Dawgs like that.
Very disappointed with the effort tonight on the defensive end, especially in the second half and by our post players. The Irish scored at will on the block and attack of the zone defense left something to be desired. And the lack of free throws both made and attempted was discouraging.
I concur about the inside defense, and the FT and 3-point shooting were horrible. We let a very doable W get away from us–somehing I saw quite a bit of last year. As I feared, Trey was more than a little rusty,and Jeremy was a lot less assertive than he has been his year to date. Let's hope we bounce back tomorrow.
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The development of European shopping centres is predicted to accelerate, with 9.1 million square metres due to be delivered over 2016 and 2017, according to a research report published today by Cushman & Wakefield.
The European Shoping Centre Development Report showed that 2015 delivered one of the lowest annual volumes of the past decade, with 4.6 million sq.m of shopping centre space opened representing a 15.8% fall on 2014. This was despite the fact that the second half of 2015 saw 3.3 million sq.m of new shopping centre space open its doors – more than double H1 figure, bringing the European total stock to 156 million sq.m by the end of the year.
Despite a slow year in 2015, shopping centre development is expected to accelerate over the next two years, with 9.1 million sq.m currently in the pipeline and due to be delivered over 2016 - 2017.
From an investment perspective, across Europe €15.5 billion was invested in shopping centres in H2 2015, representing a 16.6% year-on-year growth. The UK and Germany remain the most sought after markets, accounting for over 45% of total trading volumes.
The report shows that London retains the top position as a destination for shopping centre development. The city's low shopping centre density – 231.2 sq m per 1,000 people – combined with its strong retail sales growth of 15.8% by 2020, makes it a key market for future shopping centre development.
Elsewhere in the UK, core cities such as Edinburgh, Manchester, Birmingham, Leeds, Glasgow and Bristol will offer encouraging environments for new businesses and are forecast to see high retail sales growth over the next five years.
Madrid and Barcelona are expected to experience high retail growth, with combined retail sales of 12% by 2020. This will be a key factor in supporting future European growth. In contrast, German and French cities are forecast to display weaker growth at 6% by 2020 in core German cities and 7.5% in core French cities.
Solid growth prospects in shopping centre provision are seen in Central and Eastern Europe (CEE), including Ankara, Istanbul, Sofia, Prague and Riga. In the second half of 2015, the trend in CEE was a focus on building new sizeable shopping centre projects, such as the 110,000 sq m Zelenopark in Russia, the 61,500 sq m Podium Ankara in Turkey and the 51,000 sq m Zielone Arkady in Poland. Extensions of existing centres represented only 12% of total new space added, and this is predicted to continue, accounting for just 9% of the total amount of new space added in 2017.
Justin Taylor, Head of EMEA Retail at Cushman & Wakefield, said: "We are seeing clear and distinct regional trends. In the traditional strong, core markets of Western Europe there is an increasing move to focus on retail extensions to exisiting assets rather than new builds. Land for new centres is often scarce in these areas or complicated to bring together, so refurbishing or extending existing centres is a good option. We expect this trend to continue as landlords need to keep their offer fresh in a competitive environment.
Poland is the second largest shopping centre market in CEE (after Russia) and was the third most active in H2 2015 for development, with 362,600 sq.m of new space added across 15 new schemes and 7 extensions. One of the significant drivers of new retail space is growing demand from expanding retailers. Consumer shopping expectations are also changing as they look for an attractive retail range, interesting leisure and entertainment options alongside the rising importance of e-commerce and click-and-collect, all of which have resulted in the rising number of the redevelopment and extension projects to satisfy changing consumer patterns. The largest opening was ECE's 51,000 sq.m Zielone Arkady in Bydgoszcz. Development activity will remain stable in the future, with a higher proportion of sites expected in urban agglomeration markets, represented by eight major cities including their satellites, with populations above 400,000. Extensions will continue to complete albeit at a smaller scale than the actual 19% proportion of extension on total new space in H2 2015.
Poland was the leading country in the region accounting for nearly 61% of the total invested capital and equating to €1.5 billion. While interest from domestic investors was limited, demand from continental and global investors was increasing significantly. As interest in prime retail properties gained momentum at the end of 2015, several deals completed in Q4. Main deals included the 75,000 sq.m Bonarka shopping centre in Krakow which was acquired by American TPG for €285 million, the 59,000 sq.m Stary Browar in Poznan was sold to Deutsche Asset & Wealth Management for €285 million and the 70,500 sq.m Riviera shopping centre in Gdynia which was bought by German Union Investment for €291 million.


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Right: PhD hood on deluxe PhD gown (with PhD blue velvet).
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This entry was posted in Reading and tagged Craig Shaw Gardner, fantasy, humor, John Rawls, philosophy, reading by Richard Bowker. Bookmark the permalink.
Oh very nice! I read all three of Craig's Cineverse books actually so Temporary Monsters looks like it's worth checking out.


With three candidates vying for two seats on the Dagsboro Town Council, incumbents William Chandler and Norwood Truitt were re-elected to their seats during the town's election held on Saturday, Dec. 1.
Water service and annexation issues continue to be frustrating for some Frankford residents and the town council alike, and the two issues were raised again at the council's regular meeting on Monday, Dec. 3.
The Sussex County Council voted unanimously at its Dec. 4 meeting to approve an ordinance that would change the method of calculation for permitted density in its agricultural and residential districts.
To bring a little joy to families in need within the community, the Carpenters Union Training Center in Georgetown is collecting toys, money and gift cards to be distributed to six families of students at the Howard T. Ennis School.
In an effort to show their dedication to being good neighbors, Mountaire Farms sent a contingent of staff, from administration to on-site plant managers, to the Selbyville Town Council meeting on Dec. 3.
The Ocean View Town Council met on Dec. 4 to discuss items to be included in the first draft of its 2020-fiscal-year budget and five-year Capital Improvements Program.
The U.S. Coast Guard has been given a two-year reauthorization to continue their work on land and sea. To explain the bipartisan legislation, U.S. Sen. Tom Carper (D-Del.) visited Coast Guard Station Indian River on Dec. 3.
Millville Town Hall and its next-door neighbor, Millville United Methodist Church, will transform into a holiday shopping hub on Saturday, Dec. 8, during the sixth annual Holiday Market.
Santa's House open early, at 4 p.m.
The holidays will jingle into town at the 58th Annual Selbyville Christmas Parade on Friday, Dec. 7, at 7 p.m.
The public is being invited to make art with local artist John Donato on Monday, Dec. 10, from 5:30 to 8 p.m. The "Moving Pastels" Community Night will be hosted at Southern Delaware School of the Arts in Selbyville.
Millsboro jumped in to the Christmas spirit with a parade and tree-lighting event on Saturday, Dec. 1.
Ray Sander, president of the Delaware Botanic Gardens (DBG), announced this week that DBG Executive Director Sheryl Swed has been honored in the Annual Women in Business feature in the December issue of Delaware Today magazine.
Danita Robinson is a licensed massage therapist by profession, but she says music is her own personal therapy.
Frankford held one of its Christmas in the Park events on Wednesday, Nov. 28. The town will hold the event each Wednesday through Christmas, from 6 to 8 p.m.
It happened relatively quickly: Out of nowhere, we became tied to our mobile devices.
The Indian River School District has about two months to plan — and pass — a public referendum to build new schools and renovate others.
While there was a quorum on the dais, two members of the Sussex County Council were absent from Tuesday's meeting due to illness, leading the council to delay a vote on a proposed density ordinance.
Those driving down Muddy Neck Road will need to slow down a good 10 mph, after the Delaware Department of Transportation (DelDOT), at the request of the Ocean View Police Department, recently lowered the speed limit.
from his roots a Branch will bear fruit.
Water damage is would clearly be a threat to a 76-year-old mural. But it appears that in the midst of repairs to Selbyville Post Office, the 1942 mural there should be safe.
The Town of Bethany Beach will get in the spirit of the holiday season this Saturday, Dec. 1, with its annual Holiday Happenings celebration.
This year, Holiday Happenings combines with the kickoff of Weekend Wonderland.
Weekends in December are full of celebrating and shopping and eating and creating. All of those things, and more, are part of this year's Weekend Wonderland events in Bethany Beach.
James Farm Ecological Preserve has a way of making visitors feel alone in nature, even though another hiker might be just around the corner, having the same experience.
Aidan Kypreos, 15, of Bethany Beach is one step closer to holding the rank of Eagle with the Boy Scouts of America, after having completed his Eagle Scout project at the Delaware Veterans Home in Milford.
On Thursday, Nov. 15, the Plant, Flower & Garden Shop hosted a ribbon-cutting with the Bethany-Fenwick Area Chamber of Commerce to celebrate its expansion into Dagsboro.
The Selbyville Public Library is hosting two holiday events to put people in the Christmas spirit: the Capital Ringers on Dec. 8, and an Open House with Santa and Mrs. Claus on Dec. 15.
SoDel Concepts, a hospitality group with 10 restaurants, recently held its first class for employees interested in becoming certified beer servers.
While temperatures may have been low on Monday morning, hearts were warm as hundreds of community members gathered in tight-knit quarters with a collective goal — to give those in need a true Thanksgiving meal.
Numbers are falling into place in the Indian River School District as its Board of Education steps closer to public referendum for a new school and upgrades to four more.
Tired of the public asking about police-department challenges, the South Bethany Town Council finally made an announcement: They're working on it.
Frankford will lights up for the Christmas season this Saturday, Nov. 24, with its Christmas in the Park celebration.
The Dagsboro Town Council's November meeting was both quick and productive, with a number of minor issues getting resolved with unanimous votes from the council members present on Nov. 19.
Indian River High School students performed a military-style ceremony this month to honor the 243rd birthday of the U.S. Marine Corps.
SoDel Cares, the philanthropic arm of SoDel Concepts, recently donated $4,000 to Primeros Pasos, an early-childhood learning center in Georgetown.


Despite a furious second-half comeback, Tennessee's Final Four hopes fell short on Thursday in a 99-94 loss to Purdue in the Sweet Sixteen.
Tennessee, the third seed in the SEC Tournament, looks to begin its championship run on Friday night against Mississippi State.
Fueled by a career-high 27 points from Jordan Bone and a strong defense, No. 7 Tennessee took down fourth-ranked Kentucky in lopsided fashion on Saturday in Knoxville.
The Tennessee State Legislature introduced a bill that discusses the legalization of medical marijuana. More than half of the U.S. has already legalized medical marijuana.


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Frontiers in Plant Science
Forest Genomics and Biotechnology View all 20 Articles
Steven H. Strauss
Oregon State University, United States
Matthias Fladung
Thuenen Instute for Forest Genetics, Germany
Umeå Plant Science Centre, Umeå University, Sweden
Atsushi Watanabe
Kyushu University, Japan
The editor and reviewers' affiliations are the latest provided on their Loop research profiles and may not reflect their situation at the time of review.
Drivers for Engineering Sterile Forest Trees
Current Understanding of Reproductive Processes in Forest Trees
Engineered Sterility in Trees
Future Outlook and Challenges
Mini Review ARTICLE
Front. Plant Sci., 15 November 2018 | https://doi.org/10.3389/fpls.2018.01671
Strategies for Engineering Reproductive Sterility in Plantation Forests
Steffi Fritsche1, Amy L. Klocko2, Agnieszka Boron1, Amy M. Brunner3 and Glenn Thorlby1*
1Scion, Rotorua, New Zealand
2Department of Biology, University of Colorado Colorado Springs, Colorado Springs, CO, United States
3Department of Forest Resources and Environmental Conservation, Virginia Tech, Blacksburg, VA, United States
A considerable body of research exists concerning the development of technologies to engineer sterility in forest trees. The primary driver for this work has been to mitigate concerns arising from gene flow from commercial plantings of genetically engineered (GE) trees to non-GE plantations, or to wild or feral relatives. More recently, there has been interest in the use of sterility technologies as a means to mitigate the global environmental and socio-economic damage caused by the escape of non-native invasive tree species from planted forests. The current sophisticated understanding of the molecular processes underpinning sexual reproduction in angiosperms has facilitated the successful demonstration of a number of control strategies in hardwood tree species, particularly in the model hardwood tree Poplar. Despite gymnosperm softwood trees, such as pines, making up the majority of the global planted forest estate, only pollen sterility, via cell ablation, has been demonstrated in softwoods. Progress has been limited by the lack of an endogenous model system, long timescales required for testing, and key differences between softwood reproductive pathways and those of well characterized angiosperm model systems. The availability of comprehensive genome and transcriptome resources has allowed unprecedented insights into the reproductive processes of both hardwood and softwood tree species. This increased fundamental knowledge together with the implementation of new breeding technologies, such as gene editing, which potentially face a less oppressive regulatory regime, is making the implementation of engineered sterility into commercial forestry a realistic possibility.
Increasing global population coupled with transition to a sustainable bio-based economy is predicted to lead to growing pressure on forests to deliver wood-based products, energy, food, and ecosystem services whilst maintaining their role as major reservoirs of biodiversity. To accommodate this growing demand, it is estimated that the amount of wood we take from forests and plantations each year may need to triple by 2050 (WWF, 2015). Planted forests, which in 2015 made up 7% of forest lands, provide a means to sustainably increase production of forest products and reduce pressure on natural forests (FAO, 2015). Alongside improved silviculture, land management and other technological advances, biotech-based technologies offer tools to enhance the sustainability and productivity of planted forests (Al-Ahmad, 2018). Sterile trees have the ability to impact a number of obstacles to increasing productivity from planted forests.
Containment of Genetically Engineered Trees
Genetic engineering (GE) is able to provide solutions for many of the challenges forestry faces to sustainably increase forest production. Improved wood quantity and quality, processability, biotic, and abiotic stress tolerance and herbicide tolerance (Harfouche et al., 2011; Porth and El-Kassaby, 2014; Etchells et al., 2015; Ault et al., 2016; Zhou et al., 2017) are amongst the traits successfully demonstrated. The recent approval by the Brazilian Regulator for GE Eucalyptus that are able to grow 15–20% faster than the best existing clonal lines (Nature Biotechnology News, 2015) seems likely to lead to first large-scale commercial planting of trees.
There remain well documented regulatory and social challenges associated with commercial planting of GE trees (Porth and El-Kassaby, 2014; Strauss et al., 2016). Gene flow from transgenic trees remains a major concern, particularly as forest trees are virtually undomesticated and pollen is able to disseminate over great distances (DiFazio et al., 2004). Seeds also have the potential to spread, either locally or over distances, depending on the species. Transgene containment through the production of trees that are unable to produce fertile reproductive propagules has the ability to mitigate these concerns and prevent, or severely reduce, the flow of genes via sexual reproduction.
Invasive Tree Species
Increasing attention is being paid to the ecological, economic, and cultural damage caused by invasive tree species that have "escaped" by seed dispersal from planted forests (Breton et al., 2008; Nuñez et al., 2017). Globally, Pinus species are recognized as among the most widespread and influential of all invasive plants (Richardson and Rejmánek, 2004). These escapes, or wildings, are particularly a problem in the Southern Hemisphere where a large percentage of tree plantations are composed of exotic species (Franzese and Raffaele, 2017). South Africa, New Zealand, and Australia, who were early adopters of exotic conifer plantations, have been joined more recently by several South American nations in facing wilding challenges (Simberloff et al., 2010). For example, in New Zealand several exotic conifer species have become established and now occupy ∼1.8 million ha, and are expanding by about 6% per annum (Froude, 2011). Economic and ecological damage resulting from these wildings is challenging the license to operate, with commercially advantageous, but wilding-prone species such as Douglas-fir (Pseudotsuga menziesii). The ability to generate trees that are unable to reproduce would allow control programs to focus on the existing populations and give forest owners freedom to operate for new plantings.
Increased Wood Production and Other Benefits
The ability to either prevent reproduction or limit the development of reproductive propagules is predicted to boost growth and increase wood production in forest trees by redirecting energy and nutrients to increased vegetative growth (Strauss et al., 1995; Luis and José, 2014). Conclusive evidence for such a reproductive cost is lacking but is supported by evidence that in conifers cone production may utilize a significant proportion of the trees energy and assimilates (Cremer, 1992; Sala et al., 2012; Kramer et al., 2014). Unsurprisingly, in conifers, the long-lived female cones are more energy demanding than the generally more transient male cones (Obeso, 2002). These observations suggest that engineered sterility, particularly female sterility is likely to have a positive impact on vegetative growth and wood production. Long-term growth comparisons between sterile and reproductive trees would provide direct evidence for this and allow quantification of growth differences.
Pollen from many trees cause allergenic reactions and symptoms correlate with exposure (Buters et al., 2012). Planted forests can provide a major source of seasonal allergens (D'amato et al., 2007). For example, allergy to sugi (Cryptomeria japonica) pollen is reported to effect 26.5% of the Japanese population (Taniguchi, 2018). The ability to prevent or limit pollen production from planted forests would provide relief to allergy suffers and mitigate potential social license to operate challenges.
Both angiosperm (hardwood) and gymnosperm/conifer (softwood) trees are used as plantation species. Although they share broad similarities in their reproductive processes, there are distinct differences between them.
Angiosperm Trees
Perhaps no other plant development process has been studied more than flowering. For Arabidopsis, the in planta functions of a large number of flowering genes as well as their regulatory network context are known and studies in plants such as rice and petunia have revealed broad functional conservation (Pajoro et al., 2014). These include genes that regulate the transition to flowering, floral organ identity as well as pollen and ovule development. Although advances in sequencing have enabled the identification of flowering gene homologs in diverse angiosperm trees, there are few cases where in planta functions have been characterized in trees (Brunner et al., 2017; Klocko et al., 2018). This is due to the long non-flowering period that can last years to decades and that for most species, genetic transformation is a formidable hurdle. Trees also differ from herbaceous plants in the prolonged period between the floral transition and anthesis. In tropical species such as Eucalyptus, this occurs in one season, but temperate species exhibit indirect flowering, with flower development initiated in 1 year and completed the following year (Vining et al., 2015; Brunner et al., 2017). Thus, multi-year field trials that require monitoring of large trees and collecting flowers from the upper portion of the tree crown are typically required to demonstrate sterility or delay of flowering.
Selection of candidate genes for genetic containment in trees based on homology to Arabidopsis flowering genes and gene expression might be straightforward, but such conservation does not necessarily translate to the predicted or desired phenotype. Flowering time genes are attractive targets because prevention of flowering is easier to monitor (e.g., no need to demonstrate flowers are sterile) and to prevent resource allocation to reproduction. However, accumulating evidence supports that tree homologs of various flowering time and floral meristem identity genes have roles in both vegetative and reproductive phenology (Bohlenius et al., 2006; Bielenberg et al., 2008; Hoenicka et al., 2008; Mohamed et al., 2010; Hsu et al., 2011; Azeez et al., 2014; Tylewicz et al., 2015; Parmentier-Line and Coleman, 2016). Targeting such genes for manipulation can thus result in undesired vegetative effects, such as delayed bud flush, in addition to predicted effects on flowering or no effect on flowering (Hoenicka et al., 2012). However, promising results have also been achieved, such as the delayed flowering without growth reduction demonstrated by overexpressing the poplar ortholog of the floral repressor SHORT VEGETATIVE PHASE (SVP) (Klocko et al., 2018). Manipulation of floral organ identity genes might be less likely to have vegetative effects as these genes may show stronger conservation of reproductive-only function. For example, considerable evidence supports that the AGAMOUS (AG) subgroup of MADS-box genes have reproductive functions not only in angiosperms but also in gymnosperms (Dreni and Kater, 2014). However, even in these cases, results can differ from expectation. For example, downregulation of the conserved floral meristem identity gene LEAFY (LFY) in a male poplar genotype induced bisexual and female flowers (Klocko et al., 2018). Despite the challenges, the knowledge gained from gene function and sterility studies in trees along with more detailed and extensive genome-wide expression studies in different angiosperm trees will enable more accurate gene selection for manipulation of only-reproductive traits.
Gymnosperm Trees
Unlike angiosperms, where there is extensive knowledge of the molecular factors involved in the reproduction process, relatively little is known regarding gymnosperms. A number of putative genes have been identified through comparative analyses of orthologous angiosperm genes, tissue-specific expression analysis or genome sequencing. However, several key floral genes including FD, SQUAMOSA- (SQUA-) or SEPALLATA-like (SEP-like) seem to be absent (Becker, 2003; Abe et al., 2005; Zahn et al., 2005; Melzer et al., 2010; Karlgren et al., 2011; Jaeger et al., 2013). Initial research was able to detect orthologs to only the B- and C-genes involved in the control of meristem formation and organ identity in the developing cones (Tandre et al., 1995, 1998; Mouradov et al., 1998; Rutledge et al., 1998; Fukui et al., 2001; Sundström and Engström, 2002; Gramzow et al., 2014; Katahata et al., 2014; Uddenberg et al., 2015). More recently, ABCE model prototype transcription factors, genes that define the developmental flower organ model (ABC(DE)) in angiosperms, have been confirmed in gymnosperms (Chen et al., 2017). Conifer-specific genes such as the DEFICIENS-AGAMOUS-LIKE (DAL) and NEEDLY have also been identified but functional knowledge is limited due to the lack of angiosperm orthologs (Carlsbecker et al., 2003, 2004; Rudall et al., 2011). It is not generally possible to predict which of the many vegetative meristems will undergo the reproductive bud transition before changes are initiated making research on reproductive initiation a bold venture (Williams, 2009).
The biggest bottleneck for conifer reproduction research is the inability to carry out functional characterization in an endogenous system which prevents the definitive elucidation of gene function. Testing of gene function in angiosperm model systems has produced inconclusive results. Whilst some such studies have confirmed the function of putative orthologs, others failed to find flowering related differences, found multiple phenotypic alteration or were unable to complement mutants, highlighting the need for a reliable conifer testing system (Rutledge et al., 1998; Tandre et al., 1998; Shindo et al., 2001; Sundström and Engström, 2002; Carlsbecker et al., 2003, 2004; Nilsson et al., 2007; Shiokawa et al., 2008; Klintenas et al., 2012; Katahata et al., 2014; Liu et al., 2018). As discussed above for angiosperm trees, it might be challenging to identify flowering time gene homologs in conifers that do not have roles in vegetative development that make their manipulation for reproductive sterility problematic. For example, the gymnosperm FLOWERING LOCUS T-like subfamily has been suggested to have roles in both vegetative and reproductive phenology (Klintenas et al., 2012; Karlgren et al., 2013; Nystedt et al., 2013; Liu et al., 2016). However, the lack of characterization in an endogenous system means that the function of the sub-family members remains unresolved.
The increasingly sophisticated understanding of the molecular processes underpinning sexual reproduction described above has facilitated the successful demonstration of a number of sterility strategies in plants. Chief amongst these are strategies using ablation of reproductive cells or structures and the inactivation or suppression of genes essential for normal reproductive processes. Here, we highlight only a selection of sterility approaches and refer readers to Brunner et al. (2007) and Hoenicka et al. (2016b) for additional examples.
The use of cell or tissue-specific promoters to direct the expression of cytotoxic genes (Palmiter et al., 1987) to reproductive tissues has been widely used to investigate and modify reproductive development in plants (Goldman et al., 1994; Beals and Goldberg, 1997). Numerous examples exist of using this technology in plants to generate male and female sterility (Mariani et al., 1990; Goldman et al., 1994; De Block et al., 1997). Complete (dual male and female) sterility has also been achieved using either independent male- and female-specific promoters or a single promoter targeting both tissues simultaneously (Liu and Liu, 2008; Huang et al., 2016). Male sterility using this cell ablation strategy has been demonstrated in both hardwood and softwood trees via expression of the BARNASE gene from Bacillus amyloliquefaciens under the control of reproductive tissue-specific promoters (Table 1). A key requirement for a cell ablation strategy is a promoter that tightly directs expression of the cytotoxin to the desired reproductive tissue to prevent pleiotropic effects on non-reproductive tissues. The conservation of expression of some floral genes has facilitated the use of a number of well characterized promoters across species (Strauss et al., 1995). Indeed, an anther-specific promoter derived from Pinus radiata has been used to express the BARNASE gene in both a softwood (pine) and hardwood (Eucalyptus) tree to deliver male sterility (Zhang et al., 2012). We are unware of dual male/female BARNASE-mediated sterility being demonstrated in trees without negative pleiotropic effects (Lemmetyinen et al., 2004) but this should be possible if a suitable promoter is used.
TABLE 1. Examples of Engineered Sterility in Forest Trees.
RNA interference (RNAi) is a well proven homology-dependent gene silencing technology that involves double-stranded RNA directed against a target gene or its promoter region (Mansoor et al., 2006). Numerous demonstrations of engineered sterility through the suppression of genes essential for normal reproduction are available in angiosperm species (Wang et al., 2012). RNAi silencing has been used in angiosperm trees to engineer sterility with constructs targeting LFY and AG successfully producing sterile trees (Table 1). The production of male and female sterile plants via the use of chimeric repressors targeting transcription factors involved in flower development has also been demonstrated (Mitsuda et al., 2006; Katahata et al., 2014). In conifers the use of gene suppression methods to prevent reproduction has not been demonstrated even though such methods have been widely used to investigate wood quality traits (Wagner et al., 2005, 2009; Souza et al., 2007; Trontin et al., 2007). Attempts have been reported of expressing conifer flowering-associated genes in an endogenous system (Karlgren et al., 2013) but these studies have not directly sought to address sterility.
This lack of success in conifers reflects both a lack of fundamental knowledge regarding conifer reproduction and the inherent difficulties in working with conifers including the long timescale required for testing. For example, attempts to investigate the effects of over-expressing the Arabidopsis LFY gene in P. radiata were not informative as neither modified or control plants initiated reproduction during the 8 years that the trees were grown (NZ-EPA, 2008; Lottmann et al., 2010).
The social, legal and ecological impacts of sterile trees is still controversial (Williams, 2005; Kazana et al., 2015; Strauss et al., 2017). Although sterility provides mitigation for some of the social and ecological objections to the deployment of both GE trees and species with the potential to become invasive, this may be challenged if the sterility technology is itself GE.
The recent development of a number of new breeding technologies, including gene editing, that are already seeing widespread application in crop species (Nekrasov et al., 2017; Waltz, 2018) have great potential in forest trees. Site-directed mutagenesis would allow the inactivation of genes that are essential for normal reproductive processes and the generation of sterile trees. Gene editing-mediated mutagenesis would be particularly advantageous in forest trees where, to date, mutagenesis breeding has played an extremely limited role. The permanent inactivation of a gene would provide assurance of enduring containment and reduce concerns associated with the stability of long-term transgene expression associated with silencing of over-expression technologies (Li et al., 2008). Site directed mutagenesis via CRISPR-cas9 has been demonstrated in a number of tree species including Poplar (Fan et al., 2015) where mutagenesis of genes involved in flowering (Elorriaga et al., 2018) has also been shown. To date, gene editing has not been published in conifer species. However, the existence of a small number of natural spontaneous sterile conifer mutants (Orr-Ewing, 1977; Wilson and Owens, 2003; Rudall et al., 2011) suggest that a targeted-mutagenesis strategy would be successful if suitable targets can be identified.
Although the regulatory landscape regarding gene editing technologies remains complex, it is likely that in many jurisdictions versions of the technology that do not include foreign DNA in the final organisms will not be regulated as GMOs (Waltz, 2016; Davison and Ammann, 2017; Ishii and Araki, 2017). This would provide a more straightforward and less costly route to commercial release than is currently the case for products of GE technology (Waltz, 2018). This regulatory approach would hold particular promise in applications where sterility is a standalone trait, such as for the control of invasive tree species, rather than providing a means of containment for other (GE) traits. This strategy would require DNA-free editing technologies as outcrossing of transgenes would not be possible with sterile trees.
The second major challenge has been the inability to carry out timely prototyping of sterility constructs in commercially important species. To facilitate testing in conifers it is desirable to develop a system analogous to the Poplar model system (Jansson and Douglas, 2007; Douglas, 2017) which has allowed relatively rapid prototyping of sterility constructs (Klocko et al., 2018). Although effective transformation systems exist for a number of commercially important conifers including P. radiata, P. taeda, and Picea abies, these species have long pre-reproductive juvenile growth periods that limits their use as sterility-testing platforms (Tang and Newton, 2003; Uddenberg et al., 2015). Some conifer species are able to reproduce at a much younger age (Righter, 1939; Pharis et al., 1987; Uddenberg et al., 2013) or can be induced to undergo early reproduction. Such precocious reproduction has been demonstrated in both hardwoods and softwoods by grafting onto older rootstock (Simak, 1978; Zhang et al., 2012), and by the application of external stimuli such as hormone treatments (Pharis et al., 1965; Ross and Pharis, 1985; Meilan, 1997). Stable introduction of FT transgenes induced precocious fertile flowers in Eucalyptus (Klocko et al., 2016b) and in Populus when combined with a low temperature treatment (Hoenicka et al., 2016a). In fruit trees, viral vectors that express floral promoters or silence repressors induced early flowering (Velázquez et al., 2016; Yamagishi et al., 2016). Although these offer potential routes to earlier testing of sterility strategies, developing the required tissue culture and transformation capabilities for a new tree species remains a significant barrier.
The increasing availability of genome and transcriptome resources for forest trees is providing new insights into reproductive processes. This is reducing the reliance on non-tree model systems and providing novel species-specific knowledge of reproductive processes and candidate genes for modification. The development of gene-editing-based targeted mutagenesis is likely to be the most attractive route to engineered sterility as it offers precise and predictable modifications combined with assurance of phenotypic stability. The lack of global consensus on the regulation of gene editing technology remains a barrier to research investment and commercialization and complicates the public debate that must go hand-in-hand with progress toward implementation.
All authors listed have made a substantial, direct and intellectual contribution to the work, and approved it for publication.
This work was supported by Scion's Strategic Science Investment Funding (SSIF) from the Science and Innovation Group, Ministry of Innovation, Business and Science.
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Keywords: sterility, reproduction, forest trees, gene editing, genetic engineering, containment
Citation: Fritsche S, Klocko AL, Boron A, Brunner AM and Thorlby G (2018) Strategies for Engineering Reproductive Sterility in Plantation Forests. Front. Plant Sci. 9:1671. doi: 10.3389/fpls.2018.01671
Received: 12 August 2018; Accepted: 26 October 2018;
Published: 15 November 2018.
Steven Henry Strauss, Oregon State University, United States
Ove Nilsson, Umeå Plant Science Centre, Sweden
Atsushi Watanabe, Kyushu University, Japan
Matthias Fladung, Johann Heinrich von Thünen-Institut, Germany
Copyright © 2018 Fritsche, Klocko, Boron, Brunner and Thorlby. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
*Correspondence: Glenn Thorlby, glenn.thorlby@scionresearch.com


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Your access to the Website and use of our services are conditioned on your acceptance of and compliance with these Terms. These Terms apply to all visitors, paying clients, non-paying clients, and others who access the Website.
If you accept this Terms, you acknowledge that you have the capacity to be bound by it or if you are acting on behalf of a company or entity that you have the authority to bind such entity.
You may not accept this Terms if you are not of a legal age to form a binding contract or perform payment transactions with Redkite Digital Marketing.
Redkite Digital Marketing is an internet marketing company that specializes in providing Search Engine Optimization (SEO) outsourcing, SEO audit, website design, virtual assistance, and social media marketing management assistance. We also provide free consultations to companies and professional individual wanting to improve their website's digital marketing status.
Please read Redkite Digital Marketing Disclaimer [http://insert_disclaimer_URL_here] which is hereby incorporated into this Terms and Conditions. The Disclaimer states that by pressing "SUBMIT" and/or 'START FREE TRIAL" I agree to receive phone calls and messages from Redkite Digital Marketing.
Our Website may contain links to third-party websites that are not owned or controlled by Redkite Digital Marketing.
Redkite Digital Marketing has no control over, and assumes no responsibility for, the content, privacy policies, or practices of any third-party web sites or services. You acknowledge and agree that Redkite Digital Marketing shall not be responsible or liable, directly or indirectly, for any damage or loss caused or alleged to be caused by or in connection with use of or reliance on any such content, goods or services available on or through any such websites or services.
The contents of the Website, including logos, texts, graphics, images, photographs, editorial content, and other material are protected under both the Republic of the Philippines' copyright and trademark laws. The contents and trademark on this Website are exclusive properties of Redkite Digital Marketing. You may download or print a copy of information provided on the Website for your personal, internal, and non-commercial use only.
Redkite Digital Marketing shall in no event be responsible or liable to a client's or to any third party, whether in contract, warranty, tort (including negligence) or otherwise, for any indirect, special, incidental, consequential, exemplary, liquidated or punitive damages, including but not limited to loss of profit, revenue or business, arising in whole or in part from member's access to lasvegasluxuryrealty.com, member's use of the service or this agreement, even if Triumph Homes has been advised of the possibility of such damages.
We reserve the right, at our sole discretion, to modify or replace these Terms at any time without giving prior notice. What constitutes as a material change will be determined at our sole discretion.
y continuing to access or use our Website after those revisions become effective, you agree to be bound by the revised terms. If you do not agree to the new terms, please contact us immediately.
Please contact Redkite Digital Marketing as soon as possible for any questions you may have about these Terms.