Response of sorghum germplasm against stalk rot disease and its management

Sorghum bicolor (L.) Moench belongs to family Poaceae, ranks fifth valuable cereal crop in the world after wheat, maize, rice and barley and is one of the major fodder crop grown in Pakistan. It is affected by abiotic factors also but stalk rot caused by M. phaseolina is one among the most devastating pathogen in Pakistan, which may causes 19-63% loss in grain weight. Screening for source of resistance against this pathogen was first and foremost experiment. Among all ten varieties used for screening purpose Neelam was found to be the highly susceptible variety and Then, Jumbo Chara, Rasspary, Red sorghum India, American ever green, Sada bahar desi laal and Bahart ka vary are among the susceptible varieties. Green sweet, Fonto and Ever green India are among moderately resistant varieties. Effects of different pH and temperature levels were checked in vitro which were in favour of disease development so that this knowledge can be further orchasterized for management of this disease. Temperature range from 30-35 degree C was found to be favourable for optimum fungal growth and so far as matter of pH is concerned , pH range from 6.5-7 was found to be in favour of maximum fungal development. Both of these temperature and pH variation was studied on the basis of fungal dry mycelial weight. The efficacy of different fungicides and plant extracts were checked under lab conditions. Among all the tested fungicides Benomyl followed by Carbendazim, Topsin-M, Nativo and Metalxyl + Mancozeb was found to be the most effective fungicide in controlling fungal mycelial growth respectively. Among the plant extracts Azadirachta indica, followed by Datura stramonium, Dilbergia sisso, Calotropis procera and Moringa olifera were tested to carry maximum mycelial growth inhibitory effects respectively. But comparative study of fungicide and plants extracts against the fungal mycelial growth have revealed that plant extracts are comparatively less effective. The highest concentration of fungicides and plants extracts was observed best in producing growth inhibitory effects on fungus. The statistical analysis of data was gone by using Fisher's technique of analysis of variance and least significant difference test (LSD) was used for comparing of means of different treatments at 5% probability level.