小麦种质P10078的成株期条锈病抗性特征及遗传规律

Characterization of Resistance to Stripe Rust and Inheritance at Adult Stage in Wheat Germplasm P10078

为明确小麦抗病种质P10078的抗条锈病特征及抗病遗传规律,利用4个小麦条锈菌小种CYR32、CYR33、V26/CM42和Sull-7对P10078进行了苗期分小种鉴定,并分别在陕西杨凌人工接种病圃和甘肃天水自然诱发病圃连续多年对P10078与感病品种铭贤169及其杂交后代(F_1、F_2、F_(2∶3))进行成株期抗条锈病鉴定。结果发现,P10078苗期对CYR32、V26/CM42表现为感病(IT:7~8),对V26/CM42和Sull-7表现为抗病(IT:2),成株期对混合小种表现为高度抗病(IT:1,S:1%),表明P10078为包含全生育期抗病基因的成株期抗病品种;F_2抗感分离比为3∶1,F_(2∶3)抗感分离比为1∶2∶1,表明P10078成株期抗性由一对显性主效基因控制。P10078所含抗条锈基因为未知抗性基因。

The wheat germplasm P10078 has strong resistance to stripe rust. In order to know its char acterization of resistance to stripe rust for exploring and using the resistance sources in wheat breed- ing, the resistance was investigated using four Chinese prevalent isolates of Puccinia striiformis （CYR32, CYRa3, V26/CM42, Sull-7）, at seedling stage in greenhouse, and at adult-plant stage in Yangling by artificial inoculation and Tianshui naturally infection in field trail, respectively. The re sults showed P10078 is susceptible to CYR32 and V26/CM42（IT：7-8）, but resistant to CYR33 and Sull-7（IT：2）. It performed highly resistance to stripe rust at adult-plant stage（IT：l,S：l~） in Yan- gling and Tianshui. The inheritance of resistance was analyzed with F1 plants, F2 generation and F2. a lines derived from a cross between P10078 and the susceptible line Mingxian 169. Meanwhile, adult- plant inheritance suggested, F2 generation from the cross showed separation ratio close to 3 ： 1（x2= 0.21〈3.84） and F2.3 separation ratio close to 1 = 2 ： 1（x2 =1.93〈5.99）. This result illustrated that P10078 probably has adult-plant resistance, controlled by a dominant gene. The resistance genes to stripe rust in P10078 are unknown.