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Significance Environmental conditions strongly influence pathogen–host plant interactions. Rice blast erupts in overcast and rainy conditions, due not only to favorable environmental conditions but also to insufficient light, which reduces host resistance. Due to the importance of breeding of blast-resistant rice varieties, elucidation of light-regulated rice immunity is an important research goal. We revealed that light induces protein phosphorylation of a harvesting complex II protein, LHCB5, upon infection by the rice blast fungus Magnaporthe oryzae . Resistance governed by LHCB5 phosphorylation cosegregates with the progenies harboring the desirable haplotype promoter. This establishes the genetic basis of LHCB5-regulated resistance mediated by phosphorylation. Our study highlights a mechanism for light-dependent rice blast resistance that promises future breeding of blast-resistant rice varieties.

Controlling the height of crops plays a crucial role for their yields. The large scale utilization of semi-dwarf varieties has greatly improved crop yield, providing an effective support for world food security. In rice, a main food for over half of the world's population, a number of dwarf loci have been identified. However, most of them are recessive, such as the ‘green revolution’ gene sd1. To gain more beneficial loci for rice breeding programs, exploring new mutations is needed, especially the dominant loci which can be used broadly for hybrid breeding. Here, we isolated a novel dominant dwarf rice mutant, slr1-d5. All of the internodes of slr1-d5 are reduced. We find that the responsiveness of slr1-d5 to gibberellin (GA), GA3, was significantly reduced. Map-based cloning revealed that the dominant dwarfism of slr1-d5 was caused by an amino acid substitution in the N-terminal TVHYNP domain of rice DELLA protein, SLR1, where the conserved amino acid Pro (P) was substituted to His (H). Our findings not only further prove the pivotal role of TVHYNP motif in regulating SLR1 stability, but also provide a new dwarf source for improvement of rice germplasms.

Polyaluminum chloride (PACl) coagulant and poly (dimethyl diallyl ammonium chloride-AM) flocculants were applied to purify the wastewater from Zhanazhol oilfield, Kazakhstan. Water quality measurement showed that suspended solids content (SS) and particles size in wastewater were in excess of the reinjection standard for Kazakhstan. The SEM–EDX analysis indicated that suspended solids consisted clay particles and iron compounds. The latter could be generated from mental corrosion due to high concentration of salinity, hydrogen sulphide (H2S) and chloride ion. Jar test was conducted to investigate the effects of chemical agents dosage, settling time and Ca2+ ion concentration on removal of suspended solids from oilfield wastewater. Test results showed that PACl coagulant and DMDAAC polymer flocculant could significantly improve the separating velocity and removal rate of suspended solids. Their synergistic effect could strengthen the electric neutralization and increase the particles size. The flocculation effect increased through extending settling time. But Ca2+ concentration increase could reduce flocculation effect to a certain extent. Compared to raw wastewater, the SS content in treated wastewater could be reduced by 89.3% at optimal dose. Meanwhile, the particles size decreased from 8 microns for raw wastewater to less than 3 microns for treated wastewater. This paper had implied the characteristics of suspended solids in Zhanazhol oilfield wastewater with high salinity and hydrogen sulphide (H2S). Moreover, this study provides further understanding of the performance of poly(dimethyl diallyl ammonium chloride-acrylamide) flocculant for purifying oilfield wastewater. The results laid a good foundation for subsequent wastewater treatment to achieve the quality standard of injection water.

The translucent endosperm trait in a japonica rice variety ‘Kantou 194’ is controlled by a Wx-mq gene which is allelic to Wx locus by genetic analysis and allelic test. The amylose content analysis showed that an intermediate amylose content between those of glutinous and non-glutinous rice existed in endosperm of homozygous Wx-mq genotype. The slight changes of amylose content in different varieties and F1 grains with an identical Wx-mq genotype might be influenced by dissimilar genetic background. To identify the Wx-mq genotype simply and rapidly, a cleaved amplified polymorphic sequence (CAPS) marker was designed. The result from the molecular detection indicated that it could be used for marker-assisted selection for low amylose content varieties in rice breeding.

Line 02428h derived from the somatic cell culture of the semi-dwarf line 02428 was a recessive tall mutant in rice(Oryza sativa L.) .Plant height of the mutant 02428h was controlled by eui gene and sd-1 gene.An F2 population devel-oped from a cross between 02428h and Nanjing11 was used to map eui gene.The SSR marker RM3673,which was pub-lished in Gramene and RM0012 which was designed based on the bacterial artificial chromosome(BAC) in NCBI,was linked to eui gene in the order of RM3673-eui-RM0012 with genetic distance of 0.3 cM and 1.0 cM,respectively.These markers can be used in the molecular marker assisted selection(MAS) of eui gene.