Influence of Fertilization and Environmental Temperature on the Resistance of Bt Transgenic Cotton to Cotton Bollworm
The resistance of Bt transgenic cotton "Guo kang mian NO 1" to cotton bollworm breed in China is inferior to that of "Bao ling mian 32B" introduced from America,and their resistant degrees are evaluated at RESISTANCE and HIGH RESISTANCE respectively The insceticidal activity and the growth inhibition action of Bt tansgenic cotton increases with the increase of rates of fertilizer,and decline sharply when lower fertilizer applied The inseticidal activity to low instar larvae increases with the increase of temperature,and declines significantly under lower temperature (16℃) Ten days later,the high instar larvae with high speed growth show fairly good adaptability in spite of forced feeding under higher temperature (36℃)