Rice blast is the most devastating disease of rice (Oryza sativa L.) causing yield losses worldwide. It had been shown that partially resistant rice varieties are a useful way to control rice blast disease. Landraces are a rich source of traits governing resistance/ tolerance to biotic and abiotic stresses. Therefore, 94 upland rice varieties were used to assess the genetic diversity and population structure of nine major rice blast resistance genes (Pib, Pid2, Pigm(t), Pi9, Pi-36(t), Pi54, Pi1, Pi-2(t), and Pita). The allele frequencies of the nine major R genes varied from 4.26% to 72.34%. The 94 varieties contained a range of one to seven genes with a blast resistance allele. One variety (12CR071) had the maximum seven blast resistance genes. The polymorphism information content (PIC) value among varieties varied from 0.0815 (R36STS CAPS) to 0.5000 (pB8) with an average of 0.3784 indicating moderate genetic diversity for rice blast resistance in upland rice varieties. Cluster analysis grouped 94 varieties into two major clusters. Population structure was analyzed to understand the evolution of blast resistance genes in rice. The population structure classified the upland rice into two distinct subpopulations. Interestingly, analysis of molecular variance (AMOVA) showed that much of the variability was found within subpopulation (95%), indicating a high gene exchange between the two subpopulations. In addition, eight varieties of upland rice and two control varieties were evaluated against leaf rice blast disease using four isolates of Pyricularia oryzae. The results showed that four upland rice varieties were resistant to all isolates used. Disease reactions were negatively correlated with the genotype scores of Pib, Pigm(t), Pi54, Pi-2(t), and Pita. In addition, based on the spearman rank correlation analysis, it revealed that the Pigm(t) were positively correlated to the leaf blast resistance. These findings provide important information for new sources of resistance genes for designing future breeding program of leaf blast resistant rice varieties.

稻瘟病是水稻（Oryza sativa L.）最具破坏性的病害，在全球范围内造成产量损失。已经表明，部分抗性水稻品种是控制稻瘟病的有效方法。地方品种是控制对生物和非生物胁迫的抗性/耐受性的丰富性状来源。因此，利用94个旱稻品种对9个主要抗稻瘟病基因（Pib、Pid2、Pigm (t)、Pi9、Pi-36(t)、Pi54、Pi1、Pi-2( t）和皮塔）。九个主要R的等位基因频率基因从 4.26% 到 72.34% 不等。这 94 个品种包含 1 到 7 个具有抗稻瘟病等位基因的基因。一个品种（12CR071）具有最多七个抗稻瘟病基因。品种间的多态性信息含量（PIC）值从0.0815（R36STS CAPS）到0.5000（pB8）不等，平均为0.3784，表明旱稻品种抗稻瘟病的遗传多样性中等。聚类分析将 94 个品种分为两大类。分析群体结构以了解水稻抗稻瘟病基因的进化。人口结构将旱稻分为两个不同的亚群。有趣的是，分子方差分析 (AMOVA) 表明，在亚群 (95%) 中发现了大部分变异性，表明两个亚群之间存在高基因交换。稻瘟病菌。结果表明，四个旱稻品种对所有使用的分离株均具有抗性。疾病反应与Pib、Pigm (t)、Pi54、Pi-2(t)和Pita的基因型评分呈负相关。此外，基于spearman等级相关分析，表明Pigm（t）与叶瘟抗性呈正相关。这些发现为设计抗叶瘟水稻品种未来育种计划提供了新的抗性基因来源的重要信息。