Abstract :
Life table parameters of Lipaphis erysimi (Kaltenbach) (Hemiptera: Aphididae) were determined on four canola (Brassica napus L.) cultivars (Nathalie, Neptune, Danube, and Okapi) at 25 ±1 ˚C, 60 ±5% RH, and 16L:8D hours photoperiods. Data were analyzed using the female agespecific life table. There were significant differences in duration of nymphal developmental time and fecundity of aphid on the experimental canola cultivars. The shortest (7.13 ±0.07 day) and longest (8.91 ±0.15 day) nymphal developmental time were on Nathalie and Okapi, respectively. The rm value of L. erysimi ranged between 0.30 on Nathalie and 0.21 day1 on Okapi. The highest values of rm (0.30 ±0.00 day1), R0 (30.62 ±1.35 offspring), finite rate of increase (1.35 ±0.01 day1), and the lowest mean generation time (11.54 ±0.12 days) and DT (2.34 ±0.03 days) were recorded on Nathalie. Shorter nymphal developmental time, longer adult longevity as well as greater intrinsic rate of increase, net reproductive rates, finite rate of increase, fecundity and survivorship revealed that this pest performed well on Nathalie, Neptune and Danube cultivars. Consequently, the results indicated that canola cultivars had significant effect on life table parameters of L. erysimi and the Nathalie, Neptune, and Danube cultivars were suitable hosts for population growth of the pest.
Keywords :
Age , specific life table , Nymphal development , cv. Nathalie , cv. Danube , cv. Neptune ,
