Cereal grains are high in carbohydrates (65-75%) and low in protein (7-12%). Even their proteins are deficient in essential amino acids such as lysine and tryptophan, which the human body cannot synthesise and have to be supplied through diets.
The Indian Agricultural Research Institute (IARI) here has bred a hybrid maize — Pusa Vivek QPM 9 Improved — that is claimed to be the world’s first ever rich in lysine and tryptophan as well as pro-vitamin A. Normal maize kernels have 8-10% protein and, within that, 1.5-2.5% lysine and 0.3-0.4% tryptophan. Pro-vitamin A content, too, is only 1-2 parts per million (ppm).
The new maize hybrid has 2.67% lysine and 0.74% tryptophan in the protein, besides 8.15 parts ppm of pro-vitamin A. “The original hybrid (Vivek 9) was developed by the ICAR-Vivekananda Parvatiya Krishi Anusandhan Sansthan at Almora, Uttarakhand. The improved version incorporates an Opaque-2 gene that enhances lysine and tryptophan content, and another gene crtRB1, which results in higher levels of carotenoids (beta-carotene, alpha-carotene and beta-cryptoxanthin) that convert into vitamin A in the body. Normal maize has more of lutein and zeaxanthin, which are carotenoids that cannot convert into vitamin A,” explained Firoz Hossain, senior scientist (maize genetics and breeding), IARI.
The bio-fortified hybrid is not genetically modified, as both the Opaque-2 and crtRB1 genes are isolated from maize lines and not any alien/unrelated plants or microorganisms. It has been mainly developed for J&K, Himachal Pradesh, Uttarakhand and the North-East states, with 93-95 days maturity and average and potential yield of 5.6 and 8 tonnes per hectare, respectively. It is also suited for growing in the southern states and Maharashtra, where the average and potential yields are higher (5.9 and 9.4 tonnes) with only 83-85 days duration.
“Private sector maize hybrids are of medium (95-100 days) and late (100-120 days) maturity. In this case, yield is slightly lower, but the early maturity makes it suitable for hilly and relatively water-stressed regions. And the grain has more nutritional value,” added Hossain.
According to A.K. Singh, head of IARI’s division of genetics, the new hybrid can also be used by animal feed makers, who currently buy synthetic lysine. “Here, the grain itself has quality protein and pro-vitamin A that is natural. The poultry and pigs will, then, have more body weight gain and better feed conversion ratio,” he felt.