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Kernel size is an important agronomic trait for grain yield in maize. The purpose of this study is to map QTLs and predict candidate genes for kernel size in maize. A total of 199 F2and its F2:3lines from the cross between SG5/SG7 were developed. A composite interval mapping (CIM) method was used to detect QTLs in three environments of F2and F2:3populations. The result showed that a total of 10 QTLs for kernel size were detected, among which were five QTLs for kernel length (KL) and five QTLs for kernel width (KW). Two stable QTLs,qKW-1, andqKL-2, were mapped in all three environments. Three QTLs,qKL-1, qKW-1, andqKW-2, were overlapped with the QTLs identified from previous studies. In order to validate and fine mapqKL-2, near-isogenic lines (NILs) were developed by continuous backcrossing between SG5 as the donor parent and SG7 as the recurrent parent. Marker-assisted selection was conducted from BC2F1generation with molecular markers nearqKL-2. A secondary linkage map with six markers around theqKL-2region was developed and used for fine mapping ofqKL-2.Finally,qKL-2was confirmed in a 1.95 Mb physical interval with selected overlapping recombinant chromosomes on maize chromosome 9 by blasting with the Zea_Mays_B73 v4 genome. Transcriptome analysis showed that a total of 11 out of 40 protein-coding genes differently expressed between the two parents were detected in the identifiedqKL-2interval. GRMZM2G006080 encoding a receptor-like protein kinase FERONIA, was predicted as a candidate gene to control kernel size. The work will not only help to understand the genetic mechanisms of kernel size of maize but also lay a foundation for further fine mapping and even cloning of the promising loci.

A stable and efficient Pd(OAc)2/P(1-Nap)3[tri(1-naphthyl)phosphine] catalytic system for the addition of arylboronic acids to aldehydes has been developed. In the presence of Pd(OAc)2 and P(1-Nap)3, the addition reaction of arylboronic acids with aldehydes was carried out smoothly at 65 °C to give a variety of carbinol derivatives in good to excellent yields using a mixture of [bmim][PF6] and water as the solvent. The isolation of the products was readily performed by the extraction with diethyl ether, and the Pd(OAc)2/P(1-Nap)3/[bmim][PF6]/H2O system could be easily recycled and reused six times without significant loss of catalytic activity. Our system not only avoids the use of easily volatile THF or toluene as solvent but also solves the basic problem of palladium catalyst and these phosphine ligand reuse.

Assembling-controlled synthesis is carried out for fabrication 0 & 2D NiCu amorphous nanoalloys through the cooperation of hard-soft interfacial templates in different template-assist routes at room temperature. The controlled fabrication of 0D nanospheres and 2D ultrathin nanofilms of NiCu amorphous alloys is attributed to the synergistic effect between structure-inducing of hard collodion membrane and the reactor volume adjusting of reverse microemulsion as well as coordination of ethylenediamine ligand. The hard artificial active collodion membrane lost the structure-inducing activity after ligand ethylenediamine coordinated with metal ions. The phase transformation behavior recordings indicate that the replacement of Ni by Cu can delay phase transformation. And as the Cu concentration increases, the kinetic ordering temperature increases. The magnetic property shows that the saturation magnetizations (Ms) and coercivities (Hc) of annealed nanoalloys decrease with the increasing of Cu concentration in NiCu system.