Impact of storage period and temperature on the pathogenic behaviour of Fusarium solani on cotton (Gossypium hirsutum L.) seeds

Fusarium solani grows well at temperature of 25 ºC than at 22 ºC on potato dextrose agar medium and covered the 9 CM petri plate in 192 hours. While the best temperature for its growth was found to be 20 ºC in storage conditions. Fusarium specie, solani and semitectum (Pallidoroseum) showed increasing trend in their growth during two years span in storage. But the other fungi isolated were Aspergillus sp, Rhizopus sp., F. solani , Macrophomina phaseolina, Arthrobotrys spp , Chaetomium sp and F. semitectum (Pallidoroseum) have 1800, 2812, 200, 100, 100, 100 and 500 times spread, respectively in two years growth period in storage conditions at 25 ºC. The preponderant trend of the isolated fungi were indicating their degree of aggressiveness. The pathogen F. solani caused 100% mortality in all the treatments and reduced germination greatly in fuzzy and acid delinting practices. Cotton variety FH-901 showed resistance both in pots and fields against the pathogenic fungus F. solani. This variety gives 78 and 85% germination in pots and in fields respectively as compared with other three (FH-207, FH-114 and NIAB-78) varieties. 100% recovery of the pathogenic fungus F. solani was recorded from dried seedlings when incubated for isolation both in PDA medium and standard blotter test. The pathogen F. solani grows well at temperature of 25 ºC than the temperature of 22 ºC on synthetic potato dextrose agar medium.