Fusaric Acid Production by Different Isolates of Fusarium oxysporum f. sp. ciceris and Effect of Selected Culture Filtrate Containing Fusaric Acid on Dynamics of Plant Pigments in Chickpea

Biochemical variation with respect to fusaric acid (FA) production by various isolates of Fusarium oxysporum f. sp. ciceris (Foc) was not known and the effect of FA on the pigment dynamics of chickpea was not studied earlier.

The quantity of FA production by 14 isolates of Foc was estimated through HPLC. Further, the effect of culture filtrate (CF) containing FA of ITCC 7682 and ITCC 7681 on the dynamics of plant pigments was studied on resistant cv. WR315 and susceptible cv. JG 62 under Phytotron growing conditions during 2019–2021.

Isolate ITCC 7681 was recorded to produce the lowest quantity of FA (126.88±5.56 mg L^-1); whereas isolate ITCC 7682 produced the highest quantity of FA (820.51±13.37 mgL^-1). Isolates ITCC 7682 and ITCC 7680 were recorded to be highly virulent initiating wilt symptoms within 19–24 hours of inoculation in chickpea seedlings of susceptible cv. JG 62. Culture filtrates of ITCC 7682 and ITCC 7681 caused a reduction of chlorophyll a (15.13-72.38% and 9.24-72.38%), chlorophyll b (16.28-89.83% and 13.9597.74%), total chlorophyll (48.68-73.17% and 38.87-70.33%) and carotenoid (58.33-88.23% and 48.14-82.56%) contents 3 and 6 days after inoculation respectively. Reduction of all these pigments was significantly higher in susceptible cv. JG 62 than resistant cv. WR 315.