Evaluation of Botanical and organic substances for the management of sclerotium rolfsii causing collar rot disease in Chickpea Crop

Abstract

Pulses are basic ingredient in the diet of a vast majoriry of Indian population as they provide a perfect mix. of high biological val~e- Among the pulses. c~ickpea (Cicer arleti1111m L.) commonly known as gram, Bengal gram, homos (Arabtc}, garbanw bean (Spamsh), chestnut bean (E-gyptian) and channa (Hindi) is an important grain l~gume w_hich has wide adaptability and low input requirement crop. Chemically, chickpea seed is a good source ofprotetn, carbohydrates. fat, fiber, Ash, Calcium and Phosphorus. India grows chickpea on about8.2J ~ ha. area and producing 7.35 m.t. of grains. The crop is infected by 172 pathogens (67 fungi, 3 bacteria, 22 voruses and mycoplasma and 80 nematodes) reponed from SS countries, but only few of them like wilt, collar rot, root rot, Ascochyta blight and Botrytis gray mould are m~jor and destruCtive ones. Among soil borne diseases, collar rOI caused by S.rolftii is an important widespread and desuuctive disease. Management of crop diseases has been generally achieved by the use of S)'Tithetic pesticides but these are known to pollute the environment, soil and water, besides causing deleterious effects on human health and biosphere. A number of plants are known to possess antifungal activities which could be exploited for environmentally safe and ceofriendly method of disease management. The use of bio-agents and botanicals and organic substance may be an eiTective source to the management of coli or rot of chickpea. During the present investigation to find out the efficacy of different substances against S. rolfsii, there are e leven plnnt extracts, two antagonists (Trichoderma vir/de and Trichoderma harziamun), I I agrochemical belonging to different groups, four organic substances (Press mud, poultry manure, vermicompost and FYM} and six cakes (Neem, Mustard, Karanj, Mahua, Jetropha and Ground nut) were tested in vi••o and in ••itro. During the present in\estigation, extractS of the eleven plant species were evaluated for the fungal toxicity agaiost S rolftil by using poison food technique. All plant eX1r11ctS caused increase in inhibition in radial growth except in ease of Garlic and Aonla and Ajwain sbo"ed minimum radial growth and highest per cent inhibition at all the concentralion (2. 5 and ~e). E.wact of different organic amendments at S, I 0, IS and 20 percent concentration showed that the e"raet of poultry manure and press mud has a better performance in inhibition the growth of S. roljsii as compar< to Vermicompost and FYM. in vitro. The per cent disease control by poultry manure and press mud was 64. IS 'Yo & 47.000/o respectively at 30 days in pot experiment and similar results were found at 45 days. The extract of all the cakes were found effective in inhibiting the growth of test pad>ogcn ill vitro and ill vitro. Groundnut cake was found most promising in inhibiting the radial growth as well as decreasing the disease incidence in pots followed by Karanj cake. Studies have indicated that T. lrar:ianum and T. viride have tremendous biocontrol potential for S. rolfsii. It was found that T. har.iarrum was highly effective in reducing mycelial growth and increasing percent inhibition of S. rolftii after 72 hours of incubation. Eleven chemicals at 0.2 ·~concentration '"'retaken form-vitro screening of the fungicides. Among them four fungicides: Carboxin. Captan. Tricyclazol and Metribuzin were highly toxic to S. rolfsii with 100% inhibition. Based on present investigation. ot can be concluded that the fungi toxic properties of these different substances may be of great imponance in plant disease management, panicularly as an imponant component in intearated disease management prognunme for soil borne plant pathogens.