Herbal effect of marigold tagetes varieties on hatching and mortality of root-knot nematode, Meloidogyne incognita

摘要

Plant parts extract of fourteen marigold varieties were tested to findout their toxic effect on the hatching and mortality of root-knot nematode in laboratory condition at various dilution viz., S,S/10 and S/1000. Results confirmed the toxic nature oftissue extract to nematode by inhibiting hatching process and increased mortality. The highest toxic effect exhibited in leaf extract followed by root, flower bud and seed extract, minimal effect was seen in extract of disc and ray florets. Mortality, gradually decreased when dilution increased in contrast to hatching. Increased duration of maximum diluted extract, S/1000 had pronounced effect after 72 hrs. Maximum diluted extract S/1000 had non significant impact on mortality but its increased duration produced highest rate of mortality. Among varieties of two species, the leaf extract of African double cupid mix (T. erecta) and Bonita Bolero, EM-568, EM-561 (T. patula) was found to be more toxic in nature by increasing mortality through inhibiting hatching process. Extract upto 10 time dilution (S/10) was observed more effective upto 72 hrs. duration. Variation in mortality and hatching process in varieties Indicated the independent genetic control Application of leaf extract of marigold is only feasible control measure of root-knot nematode.