| The functional and numerical responses ofMallada basalis(Walker) larvae on Icerya aegyptiaca (Douglas) nymphs was carried out in laboratory.The functional response could be described with Holling II equation．The fitted Holling II equation of 2ndinstar and 3rd instar larvae were Na=0.6885×No/1+0.6885×0.0433No andNa=1.2085×No/1+1.2085×0.0200No, the correlation coefficient (R2) was 0.9867 and 0.9858 respectively, and the theoretical maximal consumption was 23.09 and 50.00 respectively.The results of numerical response research showed that the growth, development and reproduction of M.basalis larvae were significantly influenced by I.aegyptiaca nymphs' density.The developmental rate, female fecundity, hatching rate, female ratio ofM.basalis larvae, and adult longevity increased with an increase of I.aegyptiaca nymphs' density, then tended to be steady.The I.aegyptiacanymphs threshold for larvae survival, larvae pupation, adult emergence, offspring eggs hatching and population maintenance were respectively 5, 10, 15, 20 and30.When the preys density was 30, 40 and 50, M.basalis could grow and develop normally.There was no significant difference among sex ratio, adult longevity, fecundity and hatching rate. |
About Journal