Study on Antifungal Ability of Water Soluble Chitosan Against Green Mould Infection in Harvested Oranges is a well-researched topic, it is to be used as a guide or framework for your Academic Research
Effect of water-soluble chitosan (WSC) on green mould disease caused by Penicillium digitatum P4 was investigated in vitro and in vivo. Results of the experiments showed that P. digitatum P4 growth was much
inhibited by WSC and inhibitory effect increased as WSC concentration increased. In vitro test results indicated that complete inhibition of spore germination and mycelial growth were observed in the medium containing 1 mg/ml WSC. In the in vivo study, WSC treatments significantly reduced disease incidence and lesion diameter of
green mould disease on orange fruits. After 8 days of inoculation, the lesion diameter of orange fruits coated by 0.5%, 1%, 1.5% and 2% WSC were 5.49 cm, 5.01 cm, 3.22 cm and 1.87 cm, respectively, which smaller than that of control fruits. Biochemical experiments demonstrated that the activities of the main defense-related enzymes in flavedo tissue including chitinase and β-1,3-glucanase were enhanced by both P. digitatum P4 infection treatment and challenged with P. digitatum P4 and treated with WSC treatment. However, these enzymes of samples inoculated with P. digitatum only were lower than samples inoculated with P. digitatum P4 and treated with 2% WSC concentration. These findings suggest that the in vitro and in vivo effects of WSC on
controlling green mould disease may be associated with direct antifungal activities and the elicitation of biochemical defense responses in fruit
Citrus (Citrus sinesis L.) is consumed as fresh fruit and juice and is widely appreciated for its nutritional value and excellent taste. It is one of the most commonly produced and traded fruit crops in the world (Korsten &
Taverner, 2012). Vietnam is one of the world’s largest orange producers, ranked 20th in 2012 (Food and Agriculture Organization Statistics, 2012) and famous for many delicious orange species. Valencia 2 orange from
Nghe An Province is one of the good species with juiciness and sweet with a little acidic flavor. Citrus spp. are prone to be attacked by more than 100 diseases, among them, green mould caused by the fungus Penicillium digitatum can be responsible for up to 90% of output losses during post-harvest handling, particularly in production areas characterized by low summer rainfall. P. digitatum is considered as one of the most important post-harvest diseases of citrus fruit (Naqvi, 2004; Korsten & Taverner, 2012). For many decades, synthetic fungicides have been the main method of citrus post-harvest disease control. Although the great advantages they have brought to agricultural development, the increasing public concerns regarding health hazards and environmental pollution from chemical residues and the proliferation of resistant strains of pathogens have necessitated the intensive search for alternative strategies for the control of postharvest pathogens (Narayanasamy, 2006).
Chitosan, a deacetylated derivative of chitin, mainly consists of glucosamine units, 2-amino-2 deoxy-β-D-glucose. This natural compound is biodegradable, nontoxic and biocompatible and has diverse applications in agriculture, one among which the control of fungal diseases in crops of agricultural interest (Hernández-Lauzardo, Valle, & Guerra-Sánchez, 2011) has shown to be particularly useful in both pre- and post-harvest disease control due to its dual functions: antifungal activities and elicitation of host defense responses (Xu, Zhao, Han, & Du, 2007; Bautista-Banos et al., 2006; Hernandez-Lauzardo et al., 2011). Chitinase and β-1,3-glucanase are two kinds of pathogenesis-related protein and stimulated by infection and in response to chitosan (Barkai-Golan, 2001). However, its high viscosity and insolubility in neutral aqueous solution restrict Recent studies on chitosan have attracted interest in converting chitosan to water-soluble chitosan (Xu et al., 2007). Water-soluble chitosan, obtained by hydrolysis or degradation of chitosan, is not only water-soluble but also has shown to be more effective than chitosan in inhibiting pathogen growth and eliciting multiple plant defense responses (Yan et al., 2011). But up to now, there have been few articles that reported about the use of WSC for controlling postharvest disease. Considering the potential of WSC as an antifungal agent, the objective of this study was to investigate the in vitro and in vivo effects of WSC on Penicillium digitatum development. In addition, the activities of antifungal hydrolases were also determined to evaluate the elicitation effect of WSC.