High Temperature-preventing Cultivation Technology of Single-season Middle Rice for High Yield and High Quality in Jianghuai Area

In recent years,with the global climate change,the frequency and duration of high temperature in summer and autumn have increased,causing high temperature heat damage to summer crops such as rice and maize.From the end of July to early August is the main period of high temperature occurrence,during which the daily average temperature above 30℃is a high probability event,and even the highest temperature is above 38℃,while this period coincides with the booting-blooming-filling stage of the single-season middle rice in Jianghuai,especially the middle-season indica rice,so it often leads to the degradation of rice spikelets,pollen abortion,difficulty in pollen dispersion,and even difficulty in heading,resulting in a serious decline in the seed setting rate and poor filling of grains,which finally affect the yield and quality.Based on the goal of high-yielding high-quality rice cultivation,this paper proposed targeted technical measures for single-season middle rice from the aspects of planting time sequence optimization,selection of high-temperature-resistant varieties,population construction,fertilizer and water management technology,and how to compensate for the occurrence of unexpected disasters to promote plant growth.This study provides technical support for high-yielding high-quality stress-resistant and disaster-reducing rice cultivation technology.

Rice Blast Resistance-associated Genes Based on Different RNA-seq Resources

Rice is the main food crop in Asian countries, and rice blast causes an annual loss of rice yield of 30%-35%. Cultivating rice blast resistant varieties and discovering resistance genes are important means to prevent rice blast. By analyzing the changes in rice transcriptome expression levels before and after infection by Magnaporthe oryzae of different physiological races, we found that 5 transcripts were up-regulated together after infection, Os07 t0125500-01, Os07 t0129300-00, Os07 t0126301-01 and Os07 t0124900-01 belongs to the CAP superfamily, and Os10 t0409400-01 encodes a BURP domain containing protein.

An epi-allele of SMS causes Sanming dominant genic male sterility in rice

Male sterility is an important trait in rice for hybrid rice(Oryza sativa)breeding.However,the factors involved in dominant male sterility are largely unknown.Here,we identified a gene from Sanming dominant genic male sterile rice,named Sanming dominant male sterility(SMS),and reported that an epi-allele of this locus contributes to male sterility.Segregation analysis attributed dominant male sterility to a single locus,SMS,which we characterized using a male-sterile near isogenic line(NIL)of rice cultivar 93-11.The SMS locus was heterozygous in the male-sterile 93-11 NIL,containing an epi-allele identical to that in 93-11,and an epi-allele identical to that in rice cultivar Nipponbare,which we refer to as SMS9 and SMSN,respectively.SMS9is silent and hyper-methylated,whereas SMSNis expressed and hypo-methylated in the 93-11 NIL.Overexpressing SMSNled to male sterility.Mutations in SMS rescued the male sterility of the 93-11 NIL.Interestingly,we observed the duplication of SMSN in Nipponbare,but did not observe the duplication of SMS9in 93-11.Together,these findings suggest that the reduced methylation and enhanced expression of the SMSNepi-allele in the 93-11 NIL is responsible for its role in conferring dominant male sterility.