花生属拟直立型组野生种在栽培种改良中的应用——Ⅰ.对花生锈病和叶斑病的抗性

Utilization of Wild Erectoides Species in the Genus Arachis for the Improvement of the Cultivated Groundnut——Ⅰ. Resistance to Groundnut Rust and Leaf Spots

本文利用离体叶砂基培养法,在实验室条件下系统研究了花生属中6个拟直立型组野生种、2个花生组野生种(副对照)和1个栽培品种(对照)对花生锈病、褐斑病和黑斑病的抗性反应.对感染频率、菌斑直径、叶片脱落率、叶面坏死率和产孢指数等五种抗性成分综合分析的结果表明,所选用的野生种对锈病均表现免疫;在6个拟直立型组的野生种中,A.sp.30003、A.sp.9990和A.sp.30126未表现黑斑病症状,对褐斑病呈过敏性反应;A.sp.9993、A.sp.11462和A.sp.30134等三个种在主要抗性成分上,也明显地优于花生组的野生种及栽培种.文中还对拟直立型组的应用潜力及实验室条件下抗性成分的选择作了简要讨论.

Eight wild Arachis accessions, 6 from section Erectoides and 2 from section Arachis, were evaluated under laboratory conditions for their reactions to groundnut rust (Puccinia arachidis Speg. ) and leaf spots (Cercospora arachidi-cola Hori and Cercosporidium personatum (Berk, and Curt. ) Deighton) , with a cultivar as check. Five components of resistance were investigated, which included infection frequency, lesion diameter, defoliation, damaged leaf area and sporulation index. All the wild accessions used were immune to rust. Among the 6 Erectoides accessions, three did not develop any late leaf spot symptom, and showed hypersensitive reaction to early leaf spot pathogen; the other three were also found to have appreciable level of resistance to both leaf spot diseases under high inoculum pressure. The 2 representatives of section Arachis as well as the cultivar were, however, heavily infected by the two leaf spot pathogens under the same conditions.