downtoearth-subscribe

Genesis

Genesis AT LONG last, seed specialists have come up with a hybrid variety of wheat, an idea that has been in the offing for several decades. What acted as a deterrent was the floral biology and genetic structure of the plant. Clearing all obstacles, however, the Lafarge-Coppe group and Hybrinova, its affiliate based in Paris, have launched the first hybrid wheat variety, Hyno-Precia, in the market {Global Technoscan, 16th-31st December 1995). The wheat plant is autogamous in nature -reproduction is by means of self-fertilisation. This makes it difficult to create a hybrid variety as the basic requirement for a hybrid species is to cross-fertilise two different strains. The process then to create a hybrid in an autogamous plant, is to artificially block the production of pollen and partially sterilise one of the strains.

As the genetic method of sterilisa- tion consumes a lot of time, biologists have been experimenting with the chemical method to develop a hybridisation agent. Made of special chemical substances called gametocides, these agents inhibit the function of the male part of the plant while preserving the female entity for fertilisation. Hybri- nova was able to develop a hybrid wheat by following a three-pronged approach. In the first place, a chemical agent was developed and then sprayed a few weeks before the wheat developed ears. The agent is sprayed on the leaves of a parental strain which has been pre- selected as the female strain. In 1992, Hybrinova identified sc 2053 molecule as the hybridisation agent. This agent which destroys the food reserves of the pollen grains produced by the stamens, was discovered after the synthesis of some 600 molecules.

The second step involved the development of hybrids either from scratch or by selecting parental strains from the existing autogamous varieties. The resultant hybrids were then tested to check for their strength. And finally through the process of heterosis, only that variety was chosen which met the agronomic and technological qualities comparable or superior to the qualities of parental strain.

Hybrinova, which started its selec- tion procedure in 1984, had by 1992 produced two hybrid varieties of wheat. These were then sowed in order to evaluate the cost price of the seeds and to test the production method- ology. About 11 ha of farmland sowed with Hyno- Precia seed variety resulted in a gross output of more than the average estimated output of 50 quintals per ha. PI;1ns are now afoot to sow Hyno-Precia in about 100 ha. The hybrid wheat has a vast potential in the wheat producing countries like China, us, Russia and Canada and several European Union countries. It is hoped that they will eventually replace autogamous seeds.

Related Content