87份水稻材料中抗稻瘟病基因的分子检测

Molecular detection of blast resistance genes in 87 rice materials

【目的】探明9个抗稻瘟病基因Pi1、Pib、Pi2、Pi5、Pi9、Pita、Pigm、Pik、Pik-m在水稻材料中的分布情况,分析不同基因型的稻瘟病田间抗性水平。【方法】选择万州区甘宁镇、恩施市白果乡和湄潭县兴隆镇3个稻瘟病抗性鉴定基地,通过调查基地内水稻叶瘟和穗颈瘟的田间发病情况,筛选出抗病等级在中抗及以上的材料87份,以白果乡基地为取材点,选取供试材料的剑叶,提取DNA,利用PARMS SNP分型原理,检测9个抗稻瘟病基因在87份水稻材料中的分布情况。【结果】3个试验点的水稻材料叶瘟发病较轻,仅湄潭点有27.59%的材料表现为中感,其余材料均表现为中抗及以上;穗颈瘟发病相对较重,其中湄潭点发病最重,全部材料为中感及以上,有的甚至丧失了抗性,恩施点次之,有21.84%的材料表现为中感,万州点最轻,全部材料表现为中抗及以上。9个抗稻瘟病基因的分布情况:含Pi1基因的材料有4份;含Pib基因的材料有53份,其中杂合基因的材料5份;含Pi2基因的材料有47份,其中杂合基因的材料9份;含Pi5基因的材料有72份,其中杂合基因的材料5份;Pi9和Pik基因0份;含Pita基因的材料有36份,其中杂合基因的材料8份;含Pigm基因的材料有14份,其中杂合基因的材料3份;含Pik-m基因的材料有21份。在所测定的9个抗稻瘟病基因中只有10份水稻材料为单基因分布,多数材料至少有2个聚合基因分布,最多的含有5个聚合基因,还有2份材料中未检测到这些基因。【结论】综合稻瘟病田间抗性鉴定和抗稻瘟病基因检测结果,明确了单一稻瘟病抗性基因和聚合基因的抗性都在减弱,因此,挖掘抗稻瘟病能力强的新基因、新材料是选育抗稻瘟病新品种的有效途径。

【Objective】The distribution of nine blast resistance genes Pi1,Pib,Pi2,Pi5,Pi9,Pita,Pigm,Pik,Pik-m in rice materials was identified,and the resistance levels of different genotypes to blast in the field was analyzed.【Method】In this study,three identification bases of rice blast resistance were selected,namely Ganning town in Wanzhou district,Baiguo township in Enshi city and Xinglong town in Meitan county.By investigating the natural incidence of leaf blast and panicle blast in rice fields,87 materials with moderate resistance and above were screened out.Taking Baiguo township base as the sampling point,the flag leaves of the tested materials were selected,DNA was extracted,and the distribution of 9 blast resistance genes in 87 rice materials was detected by PARMS SNP typing principle.【Result】The incidence of leaf blast in the rice materials from the three test sites was relatively mild,only 27.59%of the materials in Meitan site showed moderate susceptibility,and the rest of the materials showed moderate resistance and above;The incidence of panicle blast was relatively serious,among which Meitan site was the most serious,all of which were moderate susceptibility and above,and some even lost their resistance,followed by Lichuan site,21.84%of which were moderate susceptibility,and Wanzhou site was the least serious,all of which were moderate resistance and above.The distribution of 9 blast resistance genes was as follows:4 materials containing Pi1 gene;53 materials containing Pib gene,including 5 materials with heterozygous gene;47 materials containing Pi2 gene,including 9 materials with heterozygous gene;72 materials containing Pi5 gene,including 5 materials with heterozygous gene;0 material containing Pi9 and Pik genes;36 materials containing Pita gene,including 8 materials with heterozygous gene;14 materials containing Pigm gene,including 3 materials with heterozygous gene;And 21 materials containing Pik-m gene.Among the 9 blast resistance genes tested,only ten rice materials have single gene distribution,most materials have at least two polymerized gene distributions,at most five polymerized genes,and these genes are not detected in two materials.【Conclusion】Based on the results of field resistance identification and gene detection of rice blast resistance,it is clear that the resistance of single rice blast resistance gene and polymerized genes is weakening.Therefore,mining new genes and materials with strong resistance to rice blast is an effective way to select new varieties resistant to rice blast.