In the previous study, the effect of orange-eyed color on mating of BPH was not clearly occurred, and the mating preference and multiple mating of female were cautiously suggested. To understand about the BPH female mate selection in the male-male competition-free conditions and the point of time for multiple mating, we designed four different combinations of the mate choice test with one virgin orange-eyed female (org/org) and two male BPH adults, orange-eyed male (org/org) and homozygous normal-eyed male (+/+). We gave the four different mating chances to female by the order of incubation (the first male and the following second male) and the incubation time (one day and days on end) of the second male. The distribution of the eye-color phenotype in F1 progeny and their hatching-order were observed in each mating combination. In the results, fourteen females out of twenty in four combinations produced progenies in accordance with mating chance priority of the first male, while three females of one combination selected the second male as a gamete. Interestingly, in three females of one combination with the continuous incubation of the second male, after eggs fertilized by the first male were continuously produced and then egg-laying was finished, progenies of the second male were started to be produced. From these results, it was suggested that mating order determines egg-laying order of female and the second mating of female would be occurred when sperm of the first male was almost exhausted in the reproductive organ.

In the previous study, we found an orange-eyed mutant of the brown planthopper (BPH). And we confirmed that it’s orange phenotype is controlled by single recessive allele in the autosome. To understand the effect of the orange eye color on mating of BPH, we designed two different combinations of the mate choice test with three virgin female and male BPH adults. The one consisted of orange-eyed female (org/org), orange-eyed male (org/org), and homozygous normal-eyed male (+/+) (female mate choice). The other was composed of orange-eyed male (org/org), orange-eyed female (org/org), and homozygous normal-eyed female (+/+) (male mate choice). In female mate choice test, four mating types could be distinguished according to the distribution of the eye-color phenotype in F1 progeny and their hatching-order in each mating pair. Two mating types showed only one eye-color phenotype, normal and orange, respectively, and the other two produced both eye-color phenotypes in a different hatching-order. In male mate choice test, both phenotypes of offsprings were also produced in most mating pairs. From these results, the effect of eye color on mating of BPH was not clearly found, but the multiple mating in both sexes and the mating preference by female are cautiously suggested.