Biocontrol Activity of Aureubasidium pullulans and Candida orthopsilosis Isolated from Tectona grandis L. Phylloplane against Aspergillus sp. in Post-Harvested Citrus Fruit

Abstract

This study aimed to isolate and identify moulds from rotten Citrus sinensis post-harvests and to investigate the activity of antagonist and biocontrol activity moulds that cause citrus fruit rotting. A total of 12 mould isolates were obtained. Following the pathogenicity test, two representative mould isolates were selected and identified based on the sequence analyses of internal transcribed spacer (ITS) regions of the rDNA. Methods used in this study include isolation of fungal postharvest diseases, pathogenicity assay, antagonism assay, growth curve analysis, in vitro biocontrol assay, and molecular phylogenetic analysis. Two isolates of fungal postharvest diseases were determined as the most destructive pathogens. The biocontrol assay showed that isolates of Y1 and Y10 were capable to reduce the growth of fungal isolates K6 and K9 and mitigate up to 100% of the damage of sweet citrus fruits after 7 days of incubation. The moulds were identified as K6 (Aspergillus flavus sensu lato) and K9 (Aspergillus niger sensu lato). Phylogenetic analysis showed that the Y10 yeast isolate was identified as Candida orthopsilosis, whereas the Y1 isolate had a close genetic relationship with Aureobasidium pullulans and possibly belongs to a new species. Further analysis is necessary to confirm this finding.

Fungal Endophytes to Combat Biotic and Abiotic Stresses for Climate-Smart and Sustainable Agriculture

“…Similarly, Aureubasidium pullulans and Candida orthopsilosi s isolated from teak plant can fight against Alternaria sp. Causing post harvest disease in citrus ( Sukmawati et al, 2021 ). Generally, antagonistic activities of fungal endophytes are coupled with the synthesis of bioactive defense-related compounds as well as bioactive natural substances ( Rustamova et al, 2022 ), such as anti-microbial, anti-fungal, and anti-viral metabolites, for instance, perfumoid, phomoenamide, dimethyl disulfide, dibenzofuran, methanethiol, ketones, b-1,3- glucan-, b-1,4- glucan-, and b-glucoside-degrading enzymes, Chitin, and β-glucans, β-1, 3 glucanases, chitinase, cellulose, protease, hydrolyzing enzymes, fumonisin, Beauvericin, etc., that contribute to control of pathogens (see Table 2 ).…”

Insight into Recent Progress and Perspectives in Improvement of Antioxidant Machinery upon PGPR Augmentation in Plants under Drought Stress: A Review

“…In addition to the aforementioned problems, many crops are subjected to various biotic and abiotic stresses. Biotic stress, generally caused by several living organisms (such as bacteria, fungi, viruses, parasites, and insects), is a major economic damaging factor in pre-harvest and post-harvest losses of major food crops [ 4 , 5 , 6 ]. The plant never develops sophisticated adaptive immunity even after repeated biotic stress exposures.…”

Synergistic Effect of Azotobacter nigricans and Nitrogen Phosphorus Potassium Fertilizer on Agronomic and Yieldtraits of Maize (Zea mays L.)

“…Some of the pathogens that have been controlled by Azotobacter sp. in the soil and on the leaf ( Kalam et al, 2020 ; Sukmawati et al, 2021 ) and ease abiotic stress in plants ( Sagar et al, 2020a , 2022a , b ; Kusale et al, 2021a , b ). Azotobacter sp.…”