›› 1998, Vol. 41 ›› Issue (4): 371-375.

• RESEARCH PAPERS • Previous Articles     Next Articles

EFFECTS OF EXOGENOUS HORMONES ON WING DIMORPHISM OF THE BROWN PLANTHOPPER, NILAPARVATA LUGENS (STAL)

Wang Jian Wu Zhenting Zhang Yijiu Chen Cexiang Xu Guihua   

  • Received:1998-02-09 Online:1998-11-20 Published:1998-05-20

Abstract: The influence of exogenous hormones on wing dimorphism of Nilaparvatalugens was studied. It was found that when the nymphs of 3rd and 4th instar were treated with juvenile hormone analog (JHA 734- II ), the numbers of brachypterous adults were increased by about 70% and 30% respectively as compared with the control. However, when the last (5th) instar nymphs were treated, the percentage of brachypterous adults did not increase. It seems that juvenile hormone could play an important role in the differentiation of wing dimorphism in N. lugens and this effect occurs at a critical stage—4th instar,The esterase activity, the contents of soluble sugar and free amino acids in the 3rd and 4th instar nymphs were raised by about 13%-14%, 24h after topical treatment with 4 /μg/mL ecdysterone (ED), but were reduced when treated with 0.31/μg/mL JHA. When the nymphs were treated with a mixture of ED and JHA, the result was similar to that with JHA solely. It is suggested that ED could promote the development of imaginal disc, which might be partly suppressed by JHA.

Key words: Nilaparvata lugens, exogenous hormones, wing dimorphism, esterase, soluble sugar, free amino acids