Response of wheat tillers at different growing stages to gametocide treatment

The effects of the gametocides Ethrel, RH-532, and RH-2956 on wheat tillers at various stages of development were studied. The gametocides were applied to Anza and Yecora 70, two spring wheat (Triticum aestivum L.) varieties, at three rates of foliar application when the main tillers were at meiosis. Ethrel was less effective in causing sterility than RH-532 and RH-2956. Anza showed greater induced sterility than Yecora 70 when treated with these gametocides. Ethrel affected only late tillers treated at or before meiosis. RH-532 and RH-2956 at the high application rate were equally effective for Anza. RH-2956 at the high application rate induced uniform and maximum sterility in early and late tillers of both Anza and Yecora 70.