PCR and Sequencing Base Detection of Gummosis Disease on Citrus aurantifolia Caused by Lasiodiplodia theobromae and Evaluation of Its Antagonisms

Abstract

Diplodia gummosis disease caused by Lasiodiplodia theobromae is an economically important postharvest fruit decay that occurs on all types of citrus grown in Bangladesh. The present investigation was conducted to isolate and identify the pathogenic fungus responsible for postharvest diplodia gummosis disease (DGD) of citrus as well as the evaluation of its biological control through microbial antagonists. DGD causing pathogen was identified by physiological, morphological and molecular methods. The pathogenic fungus was isolated from the surface of postharvest lime fruits. The optimum growth of the fungi was observed in maltose, 2% NaCl, 15% sugar and pH 7 containing PDA medium at 35⁰C. PCR products of the internal transcribed spacer (ITS) region of the fungus showed approximately 650 bp size clear band in gel electrophoresis. The amplified region of the fungus showed 99.62% similarities with the sequences of L. theobromae. Artificially inoculation of the fungus in malta, musumbi, sweet orange, lime, and guava fruits showed similar size clear band and typical diplodia gummosis disease symptom. Methanol extracts of Datura metal displayed the highest inhibition (75.25%) against the isolated fungus. Non-pathogenic fungi Trichoderma viride showed the highest antagonistic efficiency followed by Neofusicoccum mangifera against the isolated fungus. The tested soil bacteria did not show significant antagonistic activity against the isolated fungus. Therefore, the DGD of citrus control system should be integrated into the overall citrus postharvest decay control system to reduce all citrus postharvest diseases and to protect fresh citrus fruit values.

First report on molecular identification of Fusarium species causing fruit rot of mandarin (Citrus reticulata) in Bangladesh

“…Huda-Shakirah et al (2020) reported 99.53% similarity with Fusarium concentricum isolated from Hibiscus sabdariffa. The results of PCR and ITS sequencing confirm the isolated fungus as F. concentricum, which is supported by some other researcher's findings (Chowdhury et al, 2019;Hasan et al, 2020;Hyun et al, 2000).…”

Evaluation of possible biological control of Fusarium sp. using plant extracts and antagonistic species of microbes in vitro

“…The main objective of the present study was to study biological control measures for this fungus. Plant extracts are now a superior choice to control different plant pathogens, as reported by several previous studies (Hasan et al, 2020;Kareem & Al-Araji, 2017;Parveen et al, 2014). In our study, we found that the plant extracts Allium sativum, Zingiber officinale, and Coccinia grandis have significant inhibitory effects on mycelial growth of Fusarium species.…”

“…was previously isolated and identified (Accession No. MT856371) from postharvest Citrus reticulata fruit rot (Hasan et al, 2020). The culture was preserved at the Department of Genetic Engineering and Biotechnology, University of Rajshahi (Rajshahi, Bangladesh).…”

Morphomolecular and cultural characteristics and host range of Lasiodiplodia theobromae causing stem canker disease in dragon fruit

“…They recorded optimum pH 5.5-6.5 for the growth of this fungus, which indicates that slightly acidic to neutral pH is optimum for its growth. L. theobromae has a wide host range, such as banana [42], mango [34], guava [43], coconut [16], citrus [44], papaya [45], jackfruit [46], and so forth in which it causes severe diseases. In our study, we found that both the isolates of L. theobromae showed pathogenicity toward fruits of dragon fruit, banana, mango, and guava.…”