Accepted 19th July, 2021
Cucumber anthracnose caused by Colletotrichum lagenariumis responsible for about 60% yield loss of cucumber in Nigeria. Chemical control using fungicides usually cause accumulation of toxic residues, development of fungicide resistance in pathogens and adverse effect on soil and beneficial micro-organism. This study investigated the effect of hot water leaf extracts of three plant: Ricinus communis, Datura stramonium and chromoleana odoratum at three concentrations (65,50 and 30%) in the management of anthracnose disease of cucumber. In the field experiment, cucumber variety (cu999) was intercropped with maize (SUWAN-ESR) and inoculated with conidia suspension of Colletotrichum lagenariumtwo weeks after planting.After 48hours, inoculated plants were sprayed with three different concentration of D. stramonium, R. communis and C. odoratum in a randomized complete block experiment. Data collected were subjected to Analysis of Variance and means were separated using least significant difference at (p<0.05).Result from this study shows that all extracts significantly reduce(p<0.05) disease spread and the greatest control occur at 65% concentration. With the application of extract of D.stramonium, disease incidence in percentage for both sole and intercropped cucumber were 22.6% and 14.10% compared to the control (100%).Cucumber yield in the cucumber maize intercrop was significantly higher than the sole cucumber at all the tested concentration. At 65,50 and 30% concentration with extracts of R. communis, yield of cucumber in the sole crop were 262,257 and 230kg while that of intercropped were 300, 285 and 250kg respectively. Seed germination and fungi infection were generally low in the intercrop and sole plant at all tested concentrations. At 50% concentration with application of extractsC. Odoratum,seed germination percentage was 21.12% while that of intercrop was 23.52%. The study concluded that the extracts has the potential for the control of anthracnose disease in cucumber and intercropping maize with cucumber can reduce the incidence and severity of anthracnose with increased yield.
Keywords: Plant Extracts, Cucumber Anthracnose, Colletotrichum Lagenarium