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.
Bt corn is a variant of maize that has been genetically altered to express one or more proteins from the bacteria Bacillus thuringiensis. The protein is poisonous to certain insect pests and is widely used in organic gardening. The European corn borer causes about a billion dollars in damage to corn crops each year.
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.