Mapping Of Resistance Genes To Brown Planthopper In Common Wild Rice Q327 From Guangxi

Nilapatvat alugens(BPH)is widely distributed in tropical and subtropical regions.This insect belongs to the Homoptera family.It is highly harmful to rice and also parasitic on some grasses,showing certain hazards.Brown planthoppers mainly use the vascular bundles to suck the sap in the bast of rice plants,which has a detrimental effect.Related studies have found that the intake of brown planthoppers shows a certain degree of regularity.If the suckers consume sap,they will end smoking immediately.This kind of pest can use sucking mouthparts to suck a lot of sap,affecting the growth of rice and causing it to fall down and die.With the popularization of related rice dwarf varieties,the widespread use of insecticides and chemical fertilizers,the harmfulness of rice brown planthoppers to rice has been increasing,and it has shown a certain tendency of spread.By the end of the 1970s,it was harmful to Asian rice.Obviously more than other pests.Therefore,it is of great significance to excavate common wild rice genes for resistance to brown planthopper and transfer them to cultivated rice varieties.This study started with the genetic diversity and resistance screening of Oiyza rufipogon in Guangxi.The new resistance source Q327 was a descendant of the common wild rice resistant to N.lugens and the Xixiang aphids and was backcrossed.We responded to the seedling stage of Q327 seedlings.The results of multi-resistance identification showed that the average resistance level was 3.1.The results showed that the rice resistant source Q327 had a strong resistance to the emergence of the brown planthopper population in the Guangxi field,which has great research and application value.In this study,Q327 was used as the donor parent,9311 and 186S were the recipient parents,Q327 and 9311,Q327 and 186S were used to construct the primary population F2 and F3 populations.Combined with the results of previous mapping,the predecessors initially identified the rice in the 4th.The chromosomal long arm is near the primer RM16720,and the predecessors have excluded the primer RM16720(the physical distance of the NIP is 15.8 Mbp)to the large chromosomeThe direction.Later,we used the F2 and F3 populations to counteract the brown planthopper resistance gene in the source Q327,and then we mapped the gene to the SSR markers YM51(physical distance 15.8 Mbp)and YM91(physical distance 13.1 Mbp)was between 2.7 Mb and the initial location results were verified by high-throughput sequencing.The next step was fine positioning and found that the resistant parent Q327 had two regions of resistance,and the two regions were highly repetitive regions on the NIP sequence.We used the first region and the second region to separate the resistant recombined plants.Fine positioning.Finally,they were respectively located between 330 kb of primer markers YM177(physical distance 14.2 Mbp)to YM68-2(physical distance 14.5 Mbp)and YM112(physical distance 15.0 Mbp)to YM68-1(physical distance 15.2 Mbp)Between 240kb.The high-throughput sequencing analysis of the two regions of the gene was performed on the GO,KEGG,COG,NR,and SwissProt database annotations for all genes in the associated regions.The types of gene mutation in high-throughput sequencing included UPSTREAM,SYNONYMOUS CODING,and NON SYNONYMOUS CODING.There are 9 kinds of UTR 3 PRIME,INTRON,DOWNSTREAM,SYNONYMOUS CODINGSYNONYMOUS CODING,STOP GAINED and UTR 5 PRIME.For the high-throughput sequencing results,the types of mutations and the number of mutations of the candidate genes between the finely mapped regions were analyzed.The genes LOC_Os04g24750,LOC_Os04g24820,and LOC_Os04g25900 were found to have a high possibility of gene amplification.The three genes were individually subjected to fluorescent quantitative expression experiments.The gene LOC_Os04g24820 was found to be significantly different in the resistant parent Q327 and the susceptible parent 9311 after 48 hours of insect infestation.The difference was extremely significant at 96 hours after the insect was infested,but was not significant at 0,12,and 24 hours after the insect was infested.The differences;however,the gene LOC_Os04g24750 and the gene LOC_Os04g25900 were not significantly different in fluorescence quantitative expression analysis at various time periods(0 hour,12 hours,24 hours,48 hours,and 96 hours).