Burdock fructooligosaccharide induces fungal resistance in postharvest Kyoho grapes by activating the salicylic acid-dependent pathway and inhibiting browning
Highlights
► Common postharvest disease in seven kinds of fruits can be controlled by burdock fructooligosaccharide (BFO). ► A 29 percent AUDPC decrease of Botrytis cinerea in Kyoho grape has been observed. ► Salicylic acid-dependent signalling pathway and systemic acquired resistance have been activated by BFO in Kyoho grape. ► BFO delayed grape browning by delaying peroxidase and polyphenoloxidase activity in Kyoho grape skin. ► BFO restrained respiration rate, weight loss, and titratable acidity in Kyoho grape.
Introduction
Postharvest fruit losses are mainly attributed to decay caused by pathogen infection. Postharvest diseases can be controlled by synthetic fungicides (Tripathi & Dubey, 2004). However, the carcinogenicity and environmental pollution risk of fungicides has created an urgent need for new and effective technologies for controlling postharvest diseases with limited side effects. Inducing fruit systemic acquired resistance (SAR) with natural elicitors is an effective alternative. Chitooligosaccharides have been confirmed to be natural elicitors and can be derived from non-toxic and degradable biological materials with high efficiency (Holley, Yalamanchili, Moura, Ryan, & Stratmann, 2003). Postharvest diseases of pears, apples, watermelons, tomatoes, and carrots have been reported to be controlled by oligosaccharide elicitors (Meng et al., 2010, Molloy et al., 2004, Wang et al., 2009a, Yin et al., 2010). The control effects were due to induced systemic acquired resistance.
Kyoho grapes, a typical non-climacteric fruit, are an economically important grape cultivar in China. However, postharvest fungal disease caused by Botrytis cinerea, as well as browning, severely impact grape storage and transportation (Deng, Wu, & Li, 2006). It is critical to control fungal infection and browning to maintain the quality of postharvest Kyoho grapes. Chitosan has been reported to inhibit weight loss, increase the accumulation of phenol compounds and induce a series of resistance-related enzymes, such as peroxidase (POD), polyphenoloxidase (PPO), superoxide dismutase (SOD), and phenylalanine ammonia-lyase (PAL) in postharvest fruits (Meng, Li, Liu, & Tian, 2008). However, the molecular mechanism of elicitor-induced resistance in postharvest grapes remains unclear.
Burdock fructooligosaccharide (BFO) was first isolated from the root tissue of Arcitum lappa (Hao, Chen, Zhong, Chen, & Li, 2005). This compound is composed of a linear chain of twelve β-(21)-linked fructofuranose residues with a single terminal α-(1 → 2)-linked glucopyranose. BFO has no known anti-microbial activities, but it can increase the resistance of tomatoes to B. cinerea (He, Li, Chen, Hao, & Li, 2006), that of cucumbers to Colletotrichum orbiculare (Zhang, Wang, Liu, & Chen, 2009), and that of tobacco to the tobacco mosaic virus (Wang, Feng, & Chen, 2009b). BFO also increased PR1, PR2, PR3, and PAL gene expression in tomatoes (Wang et al., 2009a).
In this study, the general effects of BFO in controlling postharvest disease in different fruits were examined. We then focused on Kyoho grapes to elucidate the mechanism of BFO in increasing the resistance of grapes to B. cinerea infection and prolonging shelf life.
Section snippets
BFO preparation
BFO was extracted according to previously described methods (Hao et al., 2005). Briefly, roots of A. lappa were sliced and placed in 95 °C water for 2 h. Next, the extracted solution was precipitated with ethanol, deproteinised with chloroform, decoloured using a resin column, and separated and purified by molecular exclusion chromatography. The BFO solution (0.5% w/v) was dissolved in sterile distilled water.
Fruit and pathogen
Fruits (Table 1) were transported to our laboratory within 48 h after harvest and
BFO increased resistance of various types of postharvest fruits
The disease index Figures (Fig. 1) showed that the disease development kinesis was different between climacteric fruit and non-climacteric fruit. A dramatic disease index increase in a short time period was observed in climacteric fruit, such as apples (Fig. 1A, from 29% to 50% on the 4th day), bananas (Fig. 1C, from 36% to 53% on the 4th day), kiwifruit (Fig. 1E, from 24% to 47% on the 4th day), and pears (Fig. 1G, from 33% to 58% on the 2nd day). Non-climacteric fruit, such as grapes (Fig. 1
Discussion
Broad-spectrum protection against postharvest diseases has been confirmed using chitosan (Bautista-Baños et al., 2006). The same as a natural elicitor, BFO treatment reduced B. cinerea infection in grapes and kiwifruit, Penicillium expansum infection in apples, Penicillium italicum infection in citrus, Calletotrichum musae infection in bananas, and natural diseases in strawberries and Bartlett pears. The AUDPC (area under the disease progress curve) method was used to measure the control
Acknowledgement
This work was supported by the National High Technology Research and Development Program of China (2007AA10Z334).
References (29)
- et al.
Chitosan as a potential natural compound to control pre and postharvest diseases of horticultural commodities
Crop Protection
(2006) A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding
Analytical Biochemistry
(1976)- et al.
Chitinase and β-1,3-glucanase enzymatic activities in response to infection by Alternaria alternata evaluated in two stages of development in different tomato fruit varieties
Scientia Horticulturae
(2007) - et al.
Physiological responses and quality attributes of ‘Kyoho’ grapes to controlled atmosphere storage
LWT – Food Science and Technology
(2006) - et al.
Kinetic characterisation and thermal inactivation study of polyphenol oxidase and peroxidase from table grape (Crimson Seedless)
Food Chemistry
(2009) - et al.
Polyphenolic profile, antioxidant properties and antimicrobial activity of grape skin extracts of 14 Vitis vinifera varieties grown in Dalmatia (Croatia)
Food Chemistry
(2010) - et al.
Improvement of Hanseniaspora uvarum biocontrol activity against gray mold by the addition of ammonium molybdate and the possible mechanisms involved
Crop Protection
(2010) - et al.
Analysis of relative gene expression data using real-time quantitative PCR and the 2(-Delta Delta C(T)) method
Methods
(2001) - et al.
The relationship between water loss, lipid content, membrane integrity and LOX activity in ripe pepper fruit after storage
Postharvest Biology and Technology
(2006) - et al.
Application of 1-methylcyclopropene prior to cutting reduces wound responses and maintains quality in cut kiwifruit
Journal of Food Engineering
(2007)
Physiological responses and quality attributes of table grape fruit to chitosan preharvest spray and postharvest coating during storage
Food Chemistry
Effects of chitosan and oligochitosan on growth of two fungal pathogens and physiological properties in pear fruit
Carbohydrate Polymers
Induced resistance against Sclerotinia sclerotiorum in carrots treated with enzymatically hydrolysed chitosan
Postharvest Biology and Technology
Upgrading of grape skins: Significance of plant cell-wall structural components and extraction techniques for phenol release
Trends in Food Science & Technology
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