Effects of Insect Ecdysone and Juvenile Hormone on Reproduction of Bursaphelenchus xylophilus
The effects of the insect 20-hydroxyecdysone and juvenile hormoneⅢ on reproduction of pine wood nematode,Bursaphelenchus xylophilus,were investigated.The nematodes were treated with 7 continuous geometric concentration series of 20-hydroxyecdysone or juvenile hormone Ⅲ.The numbers of the nematodes treated with 20-hydroxyecdysone or juvenile hormone Ⅲfrom the 6th day to the 9th were significantly higher than those of the blank control and the control treated with only the nematode food ,Botrytis cinerea ( P<0.05) . During the observing period the peak of the reproduction was at 5 ×10-7 g/mL of the ecdysone and the peak value was significantly higher than those in the other concentrations .During the observing period the peak of the number of the nematodes was at 5×10-7 g/mL of the two hormones and it was significantly higher than those in the other concentrations of the hormones .The second peak of the nematode number was also found at 5 ×10-9 g/mL in both the ecdysone and the juvenile hormone .