Effect of nitrogen fertilization of corn on the development, survivorship, fecundity and body weight of Peregrinus maidis (Hom., Delphacidae)

Corn plants, Zea mays L. cv. Saccharata 'Guardian' fertilized with low (100 mg N/l), medium (300 mg N/l) and high (500 mg N/l) nitrogen doses at three times per week were used to study the effect of foliar nitrogen on the development, survivorship, reproduction, intrinsic rate of increase and adult body weight of Peregrinus maidis (Ashmead), a serious pest and the vector of maize stripe tenuvirus and maize mosaic rhabdovirus in tropical and subtropical areas. The results showed that the higher nitrogen treatments resulted in the higher nitrogen concentrations in the plants. The insects that developed on corn plants receiving more nitrogen had a significantly shorter development time and higher immature survival rate and laid significantly more eggs. Plants with higher nitrogen concentration also resulted in significantly greater adult mass. Heavier body weight is advantageous because heavier adult females have greater daily oviposition rates than lighter ones. These life history parameters as well as population intrinsic rate of increase were positively correlated with the nitrogen levels in the treated plants. The differences of adult longevity and preoviposition period among different nitrogen treatments were also significant; however, no significant correlation was found between the nitrogen fertilization rate and adult longevity, as well as preoviposition period.