Influence of post-infection temperature on three components of partial resistance in wheat to wheat leaf rust

✍ Scribed by L. H. M. Broers; S. C. Wallenburg

• Publisher: Springer
• Year: 1989
• Tongue: English
• Weight: 587 KB
• Volume: 44
• Category: Article
• ISSN: 0014-2336
• DOI: 10.1007/bf00037528

✦ Synopsis

Three components of partial resistance (PR) were studied at three post-infection temperatures using seven spring wheat genotypes differing in level of PR and two different wheat leaf rust races . The components were latency period (LP), infection frequency (IF) and urediosorus size (US) . The expression of LP was more sensitive to temperature than the expression of the other two components . LP-prolonging genes were better expressed at low temperatures than at high temperatures and cultivar differences tended to increase with decreasing temperature in both seedling and adult plant stages . The reaction of IF to temperature differed from that of LP and US, probably because IF is regulated by another mechanism than LP and US .

It is recommended to perform PR-screening tests at low rather than at high temperatures . If temperatures are maintained at about 8-13'C (night-day), seedlings can be used to screen for PR instead of the more expensive adult plant tests .

The effectiveness of PR in seedling stage at low temperatures suggests that the seedling stage may have epidemiological significance as the low temperatures (8-13° C) are relevant for seedlings in the field .