Even if enough Fe is in the soil, deficiency can occur under the following conditions: poorly drained soil, high Ca, high Mn, high pH, high P, high heavy metals, oxygen deficiency. Deficiency symptoms General: Yellow or white areas on youngest leaves. Older leaves remain green.
The Bt corn can produce unpredictable toxins and allergens into food plants and therefore into the final product. Also the Bt corn can be considered unstable as the number of copies of an inserted gene changes through later generations of the Bt corn. The low tillage is also a prime spot for a monoculture in the fields. A monoculture is where all of the crops are the same, so with this it is a perfect situation for weeds.
Crops that are genetically modified to resist herbicides or produce insecticides came on the market in 1996. According to the Organic Consumers Association, 40 percent of all U.S. crops are GMO, and 80 percent of processed foods contain GMOs.ost Corn Is Hiding. GMO corn is engineered to produce its own insecticide called Bt toxin. Some newer varieties are also resistant to weed killers or herbicides. Avoiding GMO corn can be challenging because so many food products are derived from it or contain it.