THE ROLE OF PHYTOALEXINS IN RESISTANCE TO FUSARIUM-WILT IN PIGEON PEA (CAJANUS-CAJAN)

被引：23

作者：

MARLEY, PS

HILLOCKS, RJ

机构：

[1] University of Reading, Department of Agriculture, Reading, RG6 2AT, Earley Gate

来源：

PLANT PATHOLOGY | 1993年 / 42卷 / 02期

关键词：

D O I：

10.1111/j.1365-3059.1993.tb01493.x

中图分类号：

S3 [农学（农艺学）];

学科分类号：

0901 ;

摘要：

Mechanisms of resistance to fusarium wilt (Fusarium udum) were investigated in pigeon pea cultivars from Malawi. Wilt-susceptible (Malawi local) and wilt resistant (ICP 9145) plants were stem-inoculated with a spore suspension containing 2 x 10(6)) conidia/ml of the pathogen. Occlusion of a small proportion of infected vessels was observed, but the resistant reaction appeared to depend mainly on rapid phytoalexin synthesis. Four fungitoxic isoflavonoid phytoalexins-hydroxygenistein, genistein, cajanin and cajanol-were isolated from plants 15 days after inoculation. Cajanol was identified as the main antifungal compound. The concentration of cajanol was 329.4 mug/g in the resistant cultivar as against 88.6 mug/g in the susceptible cultivar 15 days after inoculation. Crude extract from the resistant plants sampled at 24 h after inoculation contained 34.8 mug/ml of cajanol. The LD50 value of cajanol for spore germination was determined as 35 mug/ml. The cajanol content of fungus-infected ICP 9145 10 days after inoculation totally inhibited conidial germination of F. udum.

引用

页码：212 / 218

页数：7

共 32 条

[1]

Armstrong GM, 1941, PHYTOPATHOLOGY, V31, P549

[2]

BECKMAN CH, 1962, PHYTOPATHOLOGY, V52, P134

[3] LOCALIZATION OF FUSARIAL INFECTIONS IN VASCULAR TISSUE OF SINGLE-DOMINANT-GENE RESISTANT TOMATOES [J].