No abstract

The present study was planned to evaluate the efficacy of various fungicides, plant extracts, biocontrol agents and oil cakes against Macrophomina phaseolina causing dry root rot of chickpea. Among the tested biocontrol agents against Macrophomina phaseolina, T. viride was found the most effective against the fungus followed by T. harzianum, Bacillus subtalis and P. fluorescens was the least effective in reducing root rot incidence. Among the fungicides carbendazim was found most effective and recorded minimum root rot incidence. Among plant extracts, garlic extract was found most effective in reducing root rot incidence followed by neem leaf extract. In the case of organic amendments, Neem cake was the most effective in reducing the root rot incidence while wool waste and goat manure was found least effective in controlling root rot incidence.

Macrophomina phaseolina (Tassi) Goid. is a soil- and seed-borne pathogen that causes charcoal rot and various rots and blights of more than 500 crop species. Dry root rot (DRR) also called as charcoal rot which causes yield loss ranged from 25-48 per cent. The pathogen is necrotroph and infects a wide range of crops. It is observed that mycelium of M. phaseolina in cotyledons, plumule and radicle, in the naturally infected seeds of mungbean and cowpea. The disease symptoms are clearly visible from the time of emergence and can be evaluated at various stages of development of the plant. The mechanical plugging of the xylem vessels by microsclerotia, toxin production, enzymatic action and mechanical pressure during penetration lead to disease development. Management of M. phaseolina aim to reduce the number of sclerotia in soil or to minimize the contact of the inoculum and the host. Soil solarization can be a cost-effective method for management of soil borne diseases. Disease suppression by biocontrol agents such as Trichoderma harzianum, T. viride and Bacillus subtilis are the sustained manifestation of interactions among the plant, the pathogen, the biocontrol agent, the microbial community on and around the plant and the physical environment and considerably inhibited growth of M. phaseolina. Essential oils and plant extracts contain a multitude of bioactive substances against fungi, bacteria and nematodes. It has been reported that neem oil, turmeric and garlic was effective against M. phaseolina in in vitro condition. Chemical control is an effective method when seed treatment and foliar spray of carbendazim, topsin M-70, captan, thiram, mancozeb, copper oxychloride against root rot and leaf blight (Macrophomina phaseolina) topsin M-70, captan, thiram, mancozeb, copper oxychloride against root rot (Macrophomina phaseolina). As non-chemical alternative methods can be time-consuming and less effective against soilborne plant pathogens. Chemical control is an effective method of controlling some soilborne diseases in agricultural crops. Varoius workers are reported compatibility of biocontrol agents with fungicides and found that Carbendazim and biocontrol agents Trichoderma viride, T. harizianum were found effective under in vitro and pot condition.

Background: Cercospora leaf spot of mungbean [Vigna radiata (L.)] caused by Cercospora canescens. It has become a severe menace to the growers of Rajasthan in India and in general causes economic losses under changing climatic scenario. Depending upon the temperature and humidity, it spreads rapidly in susceptible varieties causing premature defoliation and reduction in size of pods and grains. In this study management was taken through botanicals and fungicides is also an important segment in the present era, in view of hazards caused by toxic chemicals or being developed resistance in pathogens to fungicides and effective means for disease control. Methods: In this field-laboratory investigation during kharif 2018 and kharif 2019 at Agronomy Farm, Sri Karan Narendra Agriculture University, Jobner, Jaipur, Rajasthan. The experiment was conducted for seven plant extracts at 5, 10 and 15 per cent concentrations were evaluated in vitro by poisoned food technique. In field experiments, further these fungicides applied as different concentrations viz., 0.1, 0.2 and 0.3% and plant extracts (at 10% conc.) were assessed by two foliar applications to control the disease. Result: Experiment was carried out in laboratory and field condition. In Plant extracts, the 100 per cent inhibition of mycelial growth was obtained with garlic extract at 10% concentration. In field conditions, two foliar applications of Hexaconazole (0.1%) were proved the most effective in reducing disease intensity (55.58%) and in increasing crop yield (56.50%) followed by Hexaconazole + Captan. In plant extracts, garlic extract (10%) proved superior in reducing disease intensity (52.85%) and in increasing crop yield (33.96%) followed by neem leaf extract.

No abstract

No abstract

No abstract