Grain size and shape are important components determining rice grain yield, and they are controlled by quantitative trait loci (QTLs). Here, we report the cloning and functional characterization of a major grain length QTL, qGL3 , which encodes a putative protein phosphatase with Kelch-like repeat domain (OsPPKL1). We found a rare allele qgl3 that leads to a long grain phenotype by an aspartate-to-glutamate transition in a conserved AVLDT motif of the second Kelch domain in OsPPKL1. The rice genome has other two OsPPKL1 homologs, OsPPKL2 and OsPPKL3 . Transgenic studies showed that OsPPKL1 and OsPPKL3 function as negative regulators of grain length, whereas OsPPKL2 as a positive regulator. The Kelch domains are essential for the OsPPKL1 biological function. Field trials showed that the application of the qgl3 allele could significantly increase grain yield in both inbred and hybrid rice varieties, due to its favorable effect on grain length, filling, and weight.

Significance: We present a draft genome of the peanut A-genome progenitor,Arachis duranensis, providing details on total genes present in the genome. Genome analysis suggests that the peanut lineage was affected by at least three polyploidizations since the origin of eudicots. Resequencing of syntheticArachistetraploids reveals extensive gene conversion since their formation by human hands. TheA. duranensisgenome provides a major source of candidate genes for fructification, oil biosynthesis, and allergens, expanding knowledge of understudied areas of plant biology and human health impacts of plants. This study also provides millions of structural variations that can be used as genetic markers for the development of improved peanut varieties through genomics-assisted breeding.

Rice qGL3 negatively regulates brassinosteroid signaling by regulating the phosphorylation level and stability of OsGSK3, which modulates OsBZR1 phosphorylation

Grain length, as a critical trait for rice grain size and shape, has a great effect on grain yield and appearance quality. Although several grain size/shape genes have been cloned, the genetic interaction among these genes and the molecular mechanisms of grain size/shape architecture have not yet to be explored. To investigate the genetic interaction between two major grain length loci of rice, GS3 and qGL3, we developed two near-isogenic lines (NILs), NIL-GS3 (GS3/qGL3) and NIL-qgl3 (gs3/qgl3), in the genetic background of 93–11 (gs3/qGL3) by conventional backcrossing and marker-assisted selection (MAS). Another NIL-GS3/qgl3 (GS3/qgl3) was developed by crossing NIL-GS3 with NIL-qgl3 and using MAS. By comparing the grain lengths of 93–11, NIL-GS3, NIL-qgl3 and NIL-GS3/qgl3, we investigated the effects of GS3, qGL3 and GS3 × qGL3 interaction on grain length based on two-way ANOVA. We found that GS3 and qGL3 had additive effects on rice grain length regulation. Comparative analysis of primary panicle transcriptomes in the four NILs revealed that the genes affected by GS3 and qGL3 partially overlapped, and both loci might be involved in brassinosteroid signaling. Our data provide new information to better understand the rice grain length regulation mechanism and help rice breeders improve rice yield and appearance quality by molecular design breeding.

Peanut is an important oilseed and a widely cultivated crop worldwide. Knowledge of the phylogenetic relationships and information on the chloroplast genomes of wild and cultivated peanuts is crucial for the evolution of peanuts. In this study, we sequenced and assembled 14 complete chloroplast genomes of Arachis. The total lengths varied from 156,287 bp to 156, 402 bp, and the average guanine–cytosine content was 36.4% in 14 Arachis species. A total of 85 simple sequence repeats (SSRs) loci were detected, including 3 dinucleotide and 82 polynucleotide SSRs. Based on 110 complete chloroplast genomes of Arachis, a phylogenetic tree was constructed, which was divided into two groups (I and II). A total of 79 different genes were identified, of which six double-copy genes (ndhB, rpl2, rpl23, rps7, ycf1, and ycf2) and one triple-copy gene (rps12) are present in all 14 Arachis species, implying that these genes may be critical for photosynthesis. The dN/dS ratios for four genes (rps18, accD, clpP, ycf1) were larger than 1, indicating that these genes are subject to positive selection. These results not only provided rich genetic resources for molecular breeding but also candidate genes for further functional gene research.