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It is a new idea to use Grey theory to solve the parameter estimation problem of small sample data. However, in the calculation of grey distance measure, there exists the problem that the resolution coefficient is fixed, so the calculation result may not be optimal. To solve this problem, a new method to select the resolution coefficient is proposed. On this basis, an improved weight calculation method is proposed. Finally, the effectiveness of the proposed algorithm is verified by simulation, and the accuracy of parameter estimation can be improved.

The fruit fly, Bactrocera tau (Walker), is one of the most important invasive worldwide pests on fruits and vegetables. In order to facilitate species identification and population genetic analysis, we isolated 22 microsatellite loci through an enriched genomic library protocol. Polymorphisms were evaluated in 30 individuals. The number of alleles per locus ranged from 2 to 9, and the observed and expected heterozygosities ranged from 0.048 to 0.862 and 0.136 to 0.852, respectively. The polymorphic information content values were from 0.124 to 0.818. Eight loci had significant deviations from the Hardy–Weinberg equilibrium. These SSR markers can be used to understand the population genetics and evolutionary patterns of the B. tau complex.

The coconut leaf beetle, Brontispa longissima, is a destructive pest of palm plants. Although its ecological and biological characteristics are well understood, its genetic information remains largely unknown. To advance our understanding of its molecular ba-sis of biology and ecology, we sequenced and analyzed its whole transcriptome by using high-throughput Illumina paired-end sequencing technology. Approximately 8.08 Gb of clean reads were generated in a single run, which were assembled by using Trinity into 41,652 unigenes with an average length of 932 bp. By sequence similarity searches for known proteins, 23,077 (55.4%) unigenes were annotated by BLASTx searches against the NCBI non-redundant protein database. Of the unigenes assembled, 18,153 and 13,733 were assigned to Gene Ontology and Clusters of Orthologous Groups of proteins, respectively. In addition, 10,415 unigenes were mapped onto 247 pathways using the Kyoto Encyclopedia of Genes and Genomes Pathway database. These transcriptomic resources will facilitate gene identification and elucidate the molecular mechanisms of biological and ecological aspects under-lying this palm pest, in order to design a new control strategy.

The effect of temperature on the developmental time, survival, and reproduction of Rhynchophorus ferrugineus (Olivier) reared on sugarcane was studied at seven constant temperatures (16, 20, 24, 28, 32, 36, and 40 degrees C). The developmental threshold temperatures and effective accumulated temperatures for the whole generation were 17.41 degrees C and 1,590.72 DD, respectively. One generation had the highest survival rate (26.67%) at 28 degrees C. The egg failed to survive at 16 and 40 degrees C. The population trend index (I = 38.22) and net reproductive rate (R(o) = 38.3) were highest at 28 degrees C. The net reproductive rate (R(o) = 3.36), intrinsic rate of increase (r(m) = 0.0028), and finite capacity of increase (lambda = 1.0028) were lowest at 20 degrees C. The mean generation time (T(o) = 85.82) was shortest at 36 degrees C. The population double time (PDT = 27.08) was shortest at 32 degrees C. Based on these studies, we concluded that the temperatures from 28 to 32 degrees C were the most suitable temperatures for the development of R. ferrugineus.