demographic parameters of the diamondback moth, plutella xylostella (lep.: plutellidae) on five rapeseed cultivars

the diamondback moth, plutella xylostella (l.) (lep.: plutellidae) is one of the most destructive insectpests of cruciferous crops throughout the world. in this research, the demographic parameters of p. xylostellawere studied on five rapeseed cultivars including licord, modena, okapi, rgsoo3 and regxkobra. theexperiments were conducted in a growth chamber at temperature of 25 â± 1â°c, 60 â± 5% rh and aphotoperiod of 16: 8 (l: d) hr. the mortality of preimaginal stages differed from 47.65 to 65.75% onmodena and regxkobra, respectively. the life expectancy of newly laid eggs and one-day-old adults ofp. xylostella was estimated as 13.48, 4.90; 14.69, 10.84; 15.39, 7.72; 16.25, 12.23; 15.06 and 6.05 dayson licord, modena, okapi, rgsoo3 and regxkobra, respectively. there was significant differencebetween net reproductive rates (ro) of the cultivars. the highest value of ro belonged to rgsoo3 (74.97 â±7.99). the longest generation time was on rgsoo3 while the shortest one belonged to the modena. theintrinsic rate of natural increase (rm) on modena was significantly differed from other cultivarsemphasizing that modena was the most sensitive cultivar to the diamondback moth than the others.