Studies on the Chemical Induction of Pollen Sterility in some Crop Plants

The effectiveness of maleic hydrazide, tri-iodobenzoic acid, yeast nucleic acid, sodium nucleate, thymine, uracil and F.W.-450 in inducing the selective abortion of pollen was studied in bread wheat, tomato and onion. Maleic hydrazide was found to be the most effective, both in wheat and onion. In wheat, complete pollen sterility occurred in plants treated with MH at 100 ppm. sprayed thrice or 250 ppm. sprayed 1 to 3 times prior to the emergence of flag leaf. In F₁ progeny of a cross performed without emasculation between MH treated C. 591 (awned) and normal N.P. 790 (awnless), 80 per cent of the plants proved to be hybrids. The effective concentration of MH was found to rise with an increase in the age of the plant in tomato. Injection of aqueous solutions of sodium nucleate (3 and 4 per cent) led to the complete abortion of pollen in onion. F.W-450, “ Gametocide “, depressed the growth of wheat plants and did not cause pollen sterility. From the present results it appears likely that a suitable chemical treatment can be standardised for causing the selective abortion of pollen in wheat, tomato and onion.