Grain appearance quality and milling quality are the main determinants of market value of rice. Breeding for improved grain quality is a major objective of rice breeding worldwide. Identification of genes/QTL controlling quality traits is the prerequisite for increasing breeding efficiency through marker-assisted selection. Here, we reported a genome-wide association study in indica rice to identify QTL associated with 10 appearance and milling quality related traits, including grain length, grain width, grain length to width ratio, grain thickness, thousand grain weight, degree of endosperm chalkiness, percentage of grains with chalkiness, brown rice rate, milled rice rate and head milled rice rate. A diversity panel consisting of 272 indica accessions collected worldwide was evaluated in four locations including Hangzhou, Jingzhou, Sanya and Shenzhen representing indica rice production environments in China and genotyped using genotyping-by-sequencing and Diversity Arrays Technology based on next-generation sequencing technique called DArTseq™. A wide range of variation was observed for all traits in all environments. A total of 16 different association analysis models were compared to determine the best model for each trait-environment combination. Association mapping based on 18,824 high quality markers yielded 38 QTL for the 10 traits. Five of the detected QTL corresponded to known genes or fine mapped QTL. Among the 33 novel QTL identified, qDEC1.1 (qGLWR1.1), qBRR2.2 (qGL2.1), qTGW2.1 (qGL2.2), qGW11.1 (qMRR11.1) and qGL7.1 affected multiple traits with relatively large effects and/or were detected in multiple environments. The research provided an insight of the genetic architecture of rice grain quality and important information for mining genes/QTL with large effects within indica accessions for rice breeding.

Most of adult female mosquitoes secrete saliva to facilitate blood sucking, digestion and nutrition, and mosquito-borne disease prevention. The knowledge of classification and characteristics of sialotranscriptome genes are still quite limited. Anopheles sinensis is a major malaria vector in China and southeast Asian countries. In this study, the An. sinensis sialotranscriptome was sequenced using Illumina sequencing technique with a total of 10 907 unigenes to be obtained and annotated in biological functions and pathways, and 10 470 unigenes were mapped to An. sinensis reference genome with 70.46% of genes having 90%-100% genome mapping through bioinformatics analysis. These mapped genes were classified into four categories: housekeeping (6632 genes), secreted (1177), protein-coding genes with function-unknown (2646) and transposable element (15). The housekeeping genes were divided into 27 classes, and the secreted genes were divided into 11 classes and 96 families. The classification, characteristics and evolution of these classes/families of secreted genes are further described and discussed. The comparison of the 1177 secreted genes in An. sinensis in the Anophelinae subfamily with 811 in Psorophora albipes in the Culicinae subfamily show that six classes/subclasses have the gene number more than twice and two classes (uniquely found in anophelines, and Orphan proteins of unique standing) are unique in the former compared with the latter, whereas four classes/subclasses are much expanded and uniquely found in the Aedes class and is unique in the later. The An. sinensis sialotranscriptome sequence data is the most complete in mosquitoes to date, and the analyses provide a comprehensive information frame for further research of mosquito sialotranscriptome.

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