Potensi Enterobacter Sp. LB04, Bacillus Cereus LB13, dan Pseudomonas Sp. LB14 Sebagai Agen Biofungisida Cendawan Penyebab Kerusakan Buah Tomat

Abstract

Postharvest fruit rot in tomatoes due to pathogenic field fungi are estimated to cause between 25 and 42% economic losses of total production globally. The primary utilization of synthetic fungicides to control postharvest losses has various negative impacts and restrictions, therefore safer and more effective approach needs to be further investigated. The recent studies have shifted imperatively towards biological control, mainly endophytic bacteria as biofungicide alternative agents which could be integrated into eco-friendly method to provide adequate control of tomato fruit losses. Thus, this study aimed to evaluate the antifungal activity and potential of Aloe vera endophytic bacteria, such as Enterobacter sp. LB04, Bacillus cereus LB13, and Pseudomonas sp. LB14 in suppressing the growth of fungi responsible for postharvest fruit rot in tomatoes. Five fungi were successfully isolated from tomatoes showing symptoms and signs of fungal induced postharvest decay, and further identified as Geotrichum sp. T001, isolate TO02, Alternaria sp. TO03, Alternaria sp. TO04, and Fusarium sp. TO05. Screening test of Aloe vera endophytic bacteria of the previous study against these fungi showed that Pseudomonas sp. LB14 performed the highest antifungal activity, significantly repressing the radial growth of Geotrichum sp. T001, Alternaria sp. TO03, Alternaria sp. TO04, and Fusarium sp. TO05 by 59.49 ± 2.98%, 66.61 ± 4.18%, 57.03 ± 4.36%, and 38.87 ± 9.00%, respectively. During in vivo examination, Pseudomonas sp. LB14 also demonstrated effectively to control fungal growth and pathogenicity, by 45.39% and 33.33% in 10-day incubation at ambient temperature of 28.25°C with relative humidity of 69.91%. These findings indicated that the endophytic bacteria, Pseudomonas sp. LB14 proved to have potential as biofungicide agent for the management of fungal induced postharvest fruit rot in tomatoes, particularly against Alternaria sp. TO03