Genetic variation in developmental times among four pure lines exhibiting specific wing form and body color in the brown planthopper, Nilaparvata lugens (Hemiptera: Auchenorrhyncha)

Abstract

Developmental times were compared among four pure lines of wing-dimorphic Nilaparvata lugens generated by successive selections for the following designated characteristics: blackish short-winged (BS), blackish long-winged (BL), yellowish brown short-winged (YS) and yellowish brown long-winged (YL). When the nymphs were reared on rice seedlings at low density, the developmental time was in the order of BS = BL \ Y-S = YL, while with an increase in rearing density, the time lengthened markedly in long-winged lines but only slightly in short-winged lines, rearranging the order to BS \ BL = YS \ YL. Among F 1 progeny of BS 9 YL, the developmental time in short-winged phenotypes was the same as those of BS lines at any of the densities tested, but the long-winged phenotypes emerged as adults at intermediate time between BS and YL lines at high density. This method of inheritance of developmental time and the differences in the duration observed among the four pure lines suggest that the genes regulating wing form and body color expression are also involved in the regulation of developmental time.

Genetic variations in the pre-feeding and pre-oviposition periods among four pure lines in the brown planthopper, Nilaparvata lugens (Hemiptera: Auchenorrhyncha:Delphacidae)

“…The four pure lines also differed in the nymphal developmental time in females in the following order: BS \ YS = BL \ YL lines (Morooka et al 2011). Further in the present study, we found differences in the pre-oviposition period as BS \ YS \ BL = YL, reflecting the differences in the pre-feeding period.…”

“…By extensive crossing experiments using these pure lines, Morooka (1992) proposed two major gene models for respective wing-form and bodycolor determination, one allele on an autosome and another allele on the X sex-chromosome. The four pure lines differ not only in body-color and wing-form expression, but also in developmental time, which is in the following order: BS \ YS = BL \ YL lines (Morooka et al 2011). These findings suggest the involvement of genes regulating body color and wing form in other life-history traits.…”

Long-wave opsin involved in body color plastic development in Nilaparvata lugens

“…While in the case of N. lugens , the regulatory mechanism underlying body color may be much more intricate than our current understanding, just like in Locusta migratoria (Orthoptera), the pigment of body color is complex and can be modified by various factors, such as endogenous hormone and population density [ 50 ]. Moreover, previous research has demonstrated that both body color and wing morphology of N. lugens contribute to the regulation of development [ 51 ]. N. lugens is widely distributed among rice-growing regions in the tropical and temperate Asian Pacific region [ 52 ], and there are variations in migration and reproductive preferences among different regional populations of N. lugens [ 53 , 54 ].…”