Rhizopus stolonifer
Postharvest Control of Soft-Rot Fungi on Grape Berries by Fungicidal Treatment and Trichoderma
Sun, 2013-02-17 21:27 — Yacoub A. M. BattaThe present research deals with the effect of postharvest treatment of grape berries with four commonly used fungicides and two forms of Trichoderma harzianum on the infection with soft-rot fungi- Rhizopus stolonifer and Mucor piriformis. This effect was evaluated by comparison of the external diameter of rot-lesion in treated and untreated berries, in addition to comparison of percent reduction in external rot-lesion diameter relative to control. Results indicated that the infection with R. stolonifer and M. piriformis was significantly reduced (P<0.05) in all treated berries in comparison with untreated control berries. The highest reduction in mean external rot-lesion diameter was obtained for both R. stolonifer and M. piriformis when inoculated berries were treated with Score® (difenoconazole) applied at 0.35%(v/v) or Switch® (cyprodinil + flodioxonil) applied at 0.20%(w/v) or formulated T. harzianum conidia in invert emulsion applied at 9.6x108 conidia/ml of formulation (13.5, 13.2, and 19.3 mm, respectively for R. stolonifer; 7.2, 7.5, and 19.2mm, respectively for M. piriformis). The greatest decrease in percent reduction in external rot-lesion diameter relative to control was also obtained for both the fungal species when inoculated berries were treated with the same type of fungicides (Score® and Switch®) and Trichoderma (formulated T. harzianum in invert emulsion) (60.9, 61.7, and 44.1%, respectively for R. stolonifer; 74.5, 73.4, and 31.9%, respectively for M. piriformis). Overall results indicate that the most effective treatment obtained on grape berries could be integrated with other control measures being usually used in grape berry-rot management plans by alternating fungicidal treatment (e.g. Score® or Switch®) with application of formulated T. harzianum conidia in invert emulsion.
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TwitterControl of Postharvest Diseases of Fruit with an Invert Emulsion Formulation of Trichoderma Harzianum Rifai
Sun, 2013-02-17 19:18 — Yacoub A. M. BattaControl of primary postharvest diseases caused by Rhizopus stolonifer, Botrytis cinerea, and Penicillium expansum on a variety of fresh fruit was evaluated with an invert emulsion formulation of Trichoderma harzianum. Diseases evaluated were quantified by the period of protection conferred by the antagonist and the diameter of decay lesions. Treatment of the various fruit species with formulated T. harzianum conidia in an invert emulsion significantly (P ≤ 0.05) reduced the mean lesion diameters of R. stolonifer on apple, pear, peach and strawberry, B. cinerea on grape, pear, strawberry, and kiwifruit, and P. expansum on grape, pear, and kiwifruit in comparison with the control treatment. Significant differences (P ≤ 0.05) were obtained in the mean percent reduction in lesion diameter caused by the same postharvest pathogens on the same fruit species due to the treatment with the formulated T. harzianum conidia relative to control treatment. The greatest mean percent reduction (86.7%) was obtained on apple fruit for the infection with R. stolonifer. Significant differences (P ≤ 0.05) were also obtained in the mean durations of the minimum protection period due to treatment with the formulated T. harzianum against the infection with the same postharvest pathogens on the same fruit species. The longest mean duration of the minimum protection period (up to 59 days) was obtained for unwounded apple fruit against the infection with R. stolonifer. Overall, the results indicate that the treatment with the invert emulsion formulation of T. harzianum protected fruit from infection by the primary postharvest pathogens of the fruit tested for up to 2 months and reduced the diameters of decay lesion up to 86% and is a promising treatment to prolong the postharvest shelf-life of fresh fruit.
