棉 花 学 报      Cotton Science    2008，20(5)：335-341

Study on the Resistance of Different Type of Upland Cotton Varieties to Cotton Leaf Roller( Sylepta derogata)
DI Jia-chun，XU Nai-yin，CHEN Xu-sheng^*，WU Qiao-juan，XIAO Song-hua，LIU Jian-guang，YIN Jian-mei
(Institute of Industrial Crops，Jiangsu Academy of Agricultural Science，Nanjing 210014，China)

Abstract：In recent years, cotton leaf roller( Sylepta derogata ) caused more damage to cotton than before. Three targets, the number of cotton leaf roller per 100 plants(NRP), the number of rolled leaf per 100 plants(NLP) and the percentage of rolled plant(PRP) were investigated among 31 cotton varieties enrolled in the cotton regional trial of the Yangtze River Valley in 2006, under the field condition with the natural population of cotton leaf roller. The results showed there was significant difference of the resistance to cotton leaf roller among the 31 varieties and significant positive relationship between each two of NRP 、 NLP and PRP. NRP, NLP and PRP all could be used as the resistance index to cotton leaf roller. The resistance of the varieties to cotton bollworm( Helicoverp armigera ) was significantly negative correlated with NRP, NLP and PRP; the correlation coefficients were -0.774^**, -0.816^**, -0.827^**, respectively. The resistance of transgenic cotton to cotton bollworm was defined as high resistance 、 moderate resistance and low resistance , the occurrence and harm of cotton leaf roller were aggravated with the reduced resistance to cotton bollworm; Compared with transgenic cotton, non-transgenic cotton ' s NRP, NLP and PRP was 11.1, 7.2, 4.6 times of transgenic cotton respectively.
    By observing the rolled leaves with dissecting microscope, it was found that there was correlation between the hair density of cotton leaf and the cotton leaf roller's ability of rolling leaf. So the hair density of cotton leaf was studied. The results showed that there was significant difference of the hair density among the 31 varieties. Though no significant liner correlation was founded between the hair density and the resistance to cotton leaf roller, it indicated that non-hairy character was resistant to cotton leaf roller, also hairy character was resistant to cotton leaf roller.
Key words：upland cotton；cotton leaf roller(Sylepta derogata)；insect resistance；transgenic insect-resistant cotton；leaf hair；shape resistance       [Full Text, 2838KB]