The genetics and nature of gene action involved in resistance to Fusarium oxysporum f. sp. niveum race 2 causing wilt in watermelon was studied. Five resistant accessions were crossed with a common susceptible parent to develop six generations for each combination. The populations were screened in two consecutive assays during June to September 2019. Based on the segregation of F2, the resistance in IC0523048, EC794455 and EC759804 was found to be governed by two major complementary dominant genes. However, the deviation from the expected ratio in BC1 progeny suggested the involvement of modifying genetic factors. The F2 and backcross progenies of BIL-53 × IIHR-9 and BIL-53 × EC794421 did not follow any of the ratios tested. Allelism test revealed the absence of any allelic relationship between IIHR9 and IC0523048 for resistance. Generation mean analysis revealed presence of epistasis in BIL-53 × EC794455 and BIL-53 × EC759804 while in the other three crosses, simple additive-dominance interaction was observed. These resistant accessions and the inheritance information generated in this study would help in incorporation of resistance to Fusarium wilt race 2 into elite commercial backgrounds.

中文翻译：

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尖孢镰刀菌抗性的遗传分析。sp. 栽培西瓜中的 niveum 种族 2 [Citrullus lanatus (Thunb.) Matsum & Nakai]

与尖孢镰刀菌抗性有关的基因作用的遗传学和性质。sp. 研究了导致西瓜枯萎的 niveum 种族 2。五个抗性种质与一个共同的易感亲本杂交，为每个组合开发六代。在 2019 年 6 月至 2019 年 9 月期间，在两次连续测定中筛选了种群。基于 F2 的分离，发现 IC0523048、EC794455 和 EC759804 中的抗性受两个主要的互补显性基因控制。然而，BC1 后代与预期比率的偏差表明涉及修改遗传因素。BIL-53 × IIHR-9 和 BIL-53 × EC794421 的 F2 和回交后代不遵循任何测试的比率。等位基因测试显示 IIHR9 和 IC0523048 之间不存在任何耐药性等位基因关系。代均值分析显示 BIL-53 × EC794455 和 BIL-53 × EC759804 中存在上位性，而在其他三个杂交中，观察到简单的加性优势相互作用。这些抗性种质和本研究中产生的遗传信息将有助于将对枯萎病 2 的抗性纳入精英商业背景。