ISSN:
1365-3059
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
The reaction of cowpea lines to naturally occurring Phytophthora vignae in the field was studied in three trials over the period 1987–89 with the aim of identifying and characterizing lines with partial resistance. Seven lines (CPI 84853, CPI 84851, CPI 65393, CPI 77359, CPI 78209. CPI 78213 and cultivar Blackeye 5) were found to be partially resistant. Partial resistance was assessed by calculating disease incidence, disease severity, time lag before onset of disease, relative area under the disease progress curve and apparent mortality and infection rates. Significant differences in some of the characters further divided the partially resistant lines into different groups. It was concluded that the characters found to be most useful in the differentiation of relative levels of partial resistance were final percentage infection, and final percentage of plants with non-killing lesions. There were also significant correlations between these variables within and between years, although the relative rankings of some of the lines changed between years. Overall, CPI 84853 and CPI 65393 showed higher levels of partial resistance in the field than the remaining lines. In general, the partially resistant lines gave variable reactions following hypocotyl inoculation with P. vignae. There were clear indications of host-isolate interactions, suggesting that partial resistance may be no more durable than complete resistance for this particular host-pathogen interaction.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1365-3059.1994.tb00548.x
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