Assessment of Volatile Organic Compounds Produced By Muscodor for Post Harvest Storage of Fruits and Vegetables

Abstract

The current study explores endophytic Indian Muscodor isolates for their mycofumigation potential to prevent decay of various fruits by gray mold B. cinerea. Nutrient (1-5% dextrose) and temperature (23-30°C) conditions were optimized for each Muscodor isolate using one factor at a time approach. The antimicrobial potential of Muscodor isolates was evaluated using VOC stress bioassay where the growth of B. cinerea was completely inhibited by #16 AMLWLS and #130 TMDSTYEL whereas the other Muscodor isolates inhibited the growth of B. cinerea by 10 to 55%. Volatiles emanated by #1639 CCSTITD did not induce any inhibitory effect on B. cinerea. Based on screening results, #16 AMLWLS and #130 TMDSTYEL were chosen for evaluation of their mycofumigation potential. The volatiles produced by #16 AMLWLS and #130 TMDSTYEL over PDA medium provided complete protection to apples, grapes and strawberries till 10th days of fumigation against B. cinerea. 25 g of wheat grain colonized Muscodor isolates also showed complete inhibition B. cinerea thereby providing shielding effect to the tested fruits whereas the same Muscodor isolates when colonized over rye grain did not exhibit any mycofumigation activity. SPME/GC-MS analysis of #16 AMLWLS exhibited a mixture of 23 volatile compounds predominantly producing 3-cyclohexen-1-ol,1-(1,5-dimethyl-4-hexenyl)-4-methyl; 1,6-dioxacyclododecane- 7,12-dione; 2,6-bis(1,1-dimethylethyl)-4-(1-oxopropyl) phenol; 2,4-di-tert-butylthiophenol and 4-octadecylmorpholine. These volatiles synergistically induce mycofumigation effect. Thus based on the above results it can be concluded that volatile produced by Indian Muscodor species possess significant mycofumigation potential which can be further applied for preventing the decay of commercially important fruits