http://www.mb.com.ph/articles/333810/aflatoxinresistant-peanut-being-developed
Aflatoxin-resistant peanut being developed
By MELODY M. AGUIBA
September 11, 2011, 8:00am
MANILA, Philippines — An aflatoxin-resistant peanut is being developed to eliminate toxin in this multivitamin-rich crop, a trait which may even be transfered to feed crop corn in the long term.
The development of an aflatoxin-resistant peanut will have a significant impact in eliminating a cancer-causing content in peanut which is considered to be an important multivitamin, multi-nutrient-rich crop.
Aflatoxin, caused by the fungus aspergillus flavus, a common mold in the environment, is an economically important toxin as it hampers international trade and depresses farmers’ income.
International Crops Research Institute for the Semi-Arid Tropics (Icrisat) Peanut Breeding Chief S.N.Nigam said Icrisat is taking both the conventional and advanced technology approach through genetic modification (GM) in developing this peanut.
The GM path involves the use of antifungal genes chitinase and glucanase and another one, lypoxygenase, a family of iron-containing enzymes that helps in dioxygenation of polyunsaturated fatty acids.
“The toxin is produced by the fungus in the seed (peanut, but) lypoxygenate blocks the metabolic pathway, so the synthesis of the toxin is stopped,” Nigam said in an interview.
The improved peanut is eyed as an alternative to staples such as rice specially in light of its climate change-mitigating impact. Being a legume, peanut has the symbiotic or friendly relationship with a bacterium called rhizobium which enables it to fix nitrogen from the atmosphere. This eliminates the need for more nitrogen-based fertilizer which produces greenhouse gas nitrous oxide.
Given the GM technique, when the development of an aflatoxin-resistant peanut will have been developed, the trait may eventually be transfered to corn whose quality and price in the market is also adversely affected by the presence of aflatoxin-forming molds.
Aflatoxin-resistance is just one of the traits being developed by Icrisat in peanut.
One of the most important traits it is developing through GM is the multivitamin-multinutrient-rich peanut that is also rich with pro-Vitamin A.
It is also trying to raise oil content in peanut from the present 48 to 50 percent.
“If I can make it 54 or 55 percent, it brings additional income to farmers becaus there’s a shortage of good quality edible oil,” he said.
However, Icrisat is also developing a peanut variety for calorie-conscious peanut-eaters. This has reduced oil content.
Icrisat Director General William D. Dar said Icrisat has been relatively fast in releasing superior varieties of its drought-prone mandate crops among which is peanut.
“We have good scientists, and we have the support of the government of India which you can’t just find elsewhere,” he said in a separate interview.
The Philippines can benefit from using these aflatoxin-resistant or nutrient-enriched varieties given their regulatory approval. And it may even be able to collaborate in their research if only the technologies are under public domain or without patent or plant exchange restrictions.
The development of the pro-Vitamin A-enhanced multivitamin-rich peanut may need at least another three years of field trials. After this, it has yet to go through government regulatory approval.
With it, a person may be able to take in a substantial amount of his recommended Vitamin A intake from a handful of peanut. However, bioavailability studies which determine the amount of effective Vitamin A absorbed into the body has yet to be conducted.
