CANCELED - Growth and Yield of Cotton Cultivars As Affected By Plant Growth Regulators - CANCELED

We investigated the effect of PGR on conventional and Bt cotton cultivars. The early cycle Bt cultivar IMA5675B2RF had the lower plant height. PGR treatment did not affect node number, however boll number was significantly decreased by MC on early cycle cultivars IMA5675B2RF and IMA5822B2RF. Boll weight was increased by MC in three cultivars (IMA08-12427, IMA5822B2RF and IMA5675B2RF) and it was correlated with a lower boll number in such cultivars. On average, MC application had no effect on seed cotton yields. Since the high boll load at the bottom of the canopy can decrease the vegetative growth, PGR may not be necessary in early Bt cultivars. In conclusion, early cycle, short, Bt cotton cultivars with high, early boll set are not prone to rank growth seem to be more sensitive to MC. Therefore PGR application is not needed in these cultivars.