Duplex PCR Detection of Pseudomonas savastanoi pv.phaseolicola and Curtobacterium flaccumfaciens pv,flaccumfaciens in Soybean

The paper aimed to establish a duplex PCR method for simultaneous detection of Pseudomonas savastanoi pv. Phaseolicola （Psp） and Curtobaeterium /accumfadens pv. Flaccumfaciens （Cff）. Based on the argK gene of Psp in GenBank, the primers PSPF1/PSPR2 were designed. The duplex PCR assay was dereloped using the combined primers PSPF1/PSPR2 and CflF1/CffR2, which were specific primers for Cff. The reaction conditions were optimized and specificity md sensitivity of the duplex PCR were tested. The expected DNA fragment was specifically amplified from the genomic DNA of Psp and Cff. Specificity was conirmed in the artificially inoculated soybean samples imparted. Thus, the duplex PCR developed in this study could be used for the simultaneous detection of Psp md Cff from imported soybean.

Histone deacetylase OsHDA706 increases salt tolerance via H4K5/K8 deacetylation of OsPP2C49 in rice

High salt is a major environmental factor that threatens plant growth and development.Increasing evidence indicates that histone acetylation is involved in plant responses to various abiotic stress;however,the underlying epigenetic regulatory mechanisms remain poorly understood.In this study,we revealed that the histone deacetylase OsHDA706 epigenetically regulates the expression of salt stress response genes in rice(Oryza sativa L.).OsHDA706 localizes to the nucleus and cytoplasm and OsHDA706 expression is significantly induced under salt stress.Moreover,oshda706 mutants showed a higher sensitivity to salt stress than the wild-type.In vivo and in vitro enzymatic activity assays demonstrated that OsHDA706 specifically regulates the deacetylation of lysines 5 and 8 on histone H4(H4K5and H4K8).By combining chromatin immunoprecipitation and mRNA sequencing,we identified the clade A protein phosphatase 2C gene,OsPP2C49,which is involved in the salt response as a direct target of H4K5 and H4K8 acetylation.We found that the expression of OsPP2C49 is induced in the oshda706 mutant under salt stress.Furthermore,the knockout of OsPP2C49 enhances plant tolerance to salt stress,while its overexpression has the opposite effect.Taken together,our results indicate that OsHDA706,a histone H4 deacetylase,participates in the salt stress response by regulating the expression of OsPP2C49 via H4K5 and H4K8 deacetylation.

A genome-wide analysis of the ASYMMETRIC LEAVES2/LATERAL ORGAN BOUNDARIES(AS2/LOB) gene family in barley(Hordeum vulgare L.)

ASYMMETRIC LEAVES2/LATERAL ORGAN BOUNDARIES（AS2/LOB） genes are a family of plant specific transcription factors, which play an important role in the regulation of plant lateral organ development and metabolism. However, a genome-wide analysis of the AS2/LOB gene family is still not available for barley. In the present study, 24 AS2-like（ASL）/LOB domain（LBD） genes were identified based on the barley（Hordeum vulgare L.） genome sequence. A phylogenetic tree of ASL/LBD proteins from barley, Arabidopsis, maize, and rice was constructed. The ASL/LBD genes were classified into two classes, class I and class II, which were divided into five and two subgroups, respectively. Genes homologous in barley and Arabidopsis were analyzed. In addition, the structure and chromosomal locations of the genes were analyzed. Expression profiles indicated that barley HvA SL/LBD genes exhibit a variety of expression patterns, suggesting that they are involved in various aspects of physiological and developmental processes. This genome-wide analysis of the barley AS2/LOB gene family contributes to our understanding of the functions of the AS2/LOB gene family.