Control of postharvest<Emphasis Type="Italic"> Rhizopus</Emphasis> rot of peach by microwave treatment and yeast antagonist

The potential of using microwave power alone, or in combination with antagonistic yeast, for control of Rhizopus stolonifer on peach, and its effects on the postharvest quality of peach were investigated. In in vitro tests, the growth of R. stolonifer was completely inhibited by a 2,450 MHz microwave heating for 2 min or more. The population density of R. stolonifer in surface wounds of microwave treatment fruits was significantly lower than that in the control. In vivo studies of inoculation of peach fruit with R. stolonifer followed by microwave treatment, Cryptococcus laurentii or both of them, microwave power and C. laurentii, as stand-alone treatments, were capable of reducing the percentage of decayed fruit from 95% in control, untreated fruit to 42.1% and 75%, respectively. However, in fruit treated with a combination of microwave power and C. laurentii, the percentage of decayed fruits was only 23.7%. The experiments on reducing natural decay development of fruit gave similar results. The microwave treatment, C. laurentii, or both of them did not impair the quality parameters of the fruit. Thus, the combination of microwave and C. laurentii could be an alternative to chemicals for control of postharvest Rhizopus rot on peach fruits.     

Suppression of postharvest blue mould of apple fruit by Cryptococcus laurentii and N6‐benzyladenine

BACKGROUND: Cryptococcus laurentii is a well‐known postharvest yeast antagonist. N⁶‐benzyladenine (6‐BA), a cytokinin plant hormone, has a role in retarding ripening and senescence of harvested produce. This study was conducted to evaluate the efficacy of C. laurentii and 6‐BA in reducing the blue mould disease of apple fruit. RESULTS: The combination of C. laurentii with 6‐BA (20 µg mL^?1) was more effective in suppressing the Penicillium expansum infection in apple fruit wounds than C. laurentii alone, although 6‐BA (20 µg mL^?1) alone neither affected the growth of C. laurentii nor reduced the incidence of the blue mould disease in vivo. Moreover, treatment of apple fruit with C. laurentii and 6‐BA (20 µg mL^?1) resulted in stimulation of superoxide dismutase activity but in inhibition of the increase in peroxidase activity. CONCLUSION: 6‐BA (20 µg mL^?1) could enhance the efficacy of C. laurentii in reducing the postharvest blue mould disease of apple fruit, which offered great potential in minimizing the postharvest decay of apple fruit in an integrated pest management strategy. Copyright © 2008 Society of Chemical Industry     

Control of anthracnose rot and quality deterioration in loquat fruit with methyl jasmonate

BACKGROUND: Loquat (Eriobotrya japonica Lindl.) fruit has a short shelf‐life, mainly due to fungal decay. Current control of postharvest disease of the fruit is mainly dependent on fungicides. However, because of the increasing consumer concern over food safety, there is an urgent need to search for effective alternatives to control disease. The objective of this work was to determine the efficacy of methyl jasmonate (MeJA) in controlling anthracnose rot caused by Colletotrichum acutatum and maintaining quality of loquat fruit. RESULTS: Loquat fruit were treated with 10 µmol L^?1 MeJA and wound inoculated with C. acutatum spore suspension of 1.0 × 10⁵ spores mL^?1 24 h after treatment, and then stored at 20 °C for 6 days. The percentage of infected wounds showing decay symptom was reduced from 54.4% to 16.7% and the lesion diameter was reduced from 7.26 mm to 4.00 mm by MeJA treatment on the 4th day after inoculation. MeJA treatment induced higher activities of two defense‐related enzymes—chitinase and β‐1,3‐glucanase—during 6 days storage. Meanwhile, the treatment inhibited increases in fruit firmness and internal browning index, and maintained higher extractable juice rate and total soluble solids and titratable acidity contents, thereby delaying the development of flesh leatheriness. CONCLUSION: MeJA treatment effectively inhibited anthracnose rot and maintained quality in loquat fruit. Inhibition of the disease was mainly because of resistance induced in loquat fruit by MeJA. A postharvest application of MeJA could be an alternative to chemical fungicides for control of postharvest disease in loquat fruit. Copyright © 2008 Society of Chemical Industry     

Combined use of UV‐C irradiation and heat treatment to improve postharvest life of strawberry fruit

The effects of UV‐C (4.1 kJ m^?2) and heat treatment (45 °C, 3 h in air) either separately or combined on the quality of strawberries (Fragaria × ananassa cv Seascape) at the 75 or 50% surface red ripening stage were assessed, the latter stage being used only in the firmness test. In addition, the development of surface fungal infections was followed and in vitro germination assays on conidia of Botrytis cinerea and Rhizopus stolonifer performed. Both heat and combined treatments, decreased hue and delayed changes of the L* parameter. All treatments reduced the accumulation of anthocyanins. Control fruit softened most while fruit treated by the combined method were the firmest. The combined treatment reduced fungal infections and delayed in vitro germination of Botrytis cinerea conidia. After 2 days at 20 °C, treated fruit had lower amount of phenolics than the control. Neither the heat nor UV‐C irradiation modified the total sugar content, although the combined treatment decreased it slightly relative to the control. Titratable acidity increased through storage at 20 °C in all fruit, but no differences between control and treated fruit were detected. The combination of UV‐C and heat treatments enhanced the benefits of applying each treatment separately, and could be useful to improve and extend strawberry fruit postharvest life. Copyright © 2004 Society of Chemical Industry     

Effect of benzyl isothiocyanate on tomato fruit infection development by Alternaria alternata

Benzyl isothiocyanate (BITC) is known to be a strong antifungal compound in vitro against different fungi. The effectiveness of benzyl isothiocyanate to control Alternaria alternata growth in vitro and in vivo was tested. BITC in vitro activity was evaluated in A alternata growing on potato dextrose agar and exposed to 0.025, 0.05, 0.1, 0.2 or 0.4 mg ml^?1. In vivo activity was evaluated by exposing A alternata‐inoculated tomato fruits for either 18 or 36 h to 0.28 or 0.56 mg ml^?1 BITC packed on low‐density polyethylene film (LDPF) bags. Additionally, the effect of BITC on post‐harvest physiology and tomato quality throughout storage at 20 °C was evaluated daily by monitoring respiration rate and ethylene production, whereas total soluble solids, pH, titratable acidity and fresh weight loss were measured every 3 days. Results showed that the minimal inhibitory concentration of BITC in vitro was 0.1 mg ml^?1. A combined use of 0.56 mg ml^?1 BITC with LDPF for 18 h was the optimum treatment to control Alternaria rot in packed tomato fruit. No effect of BITC on respiration rate, ethylene production, total soluble solids, pH, weight loss and titratable acidity was observed. Results suggest that BITC can be used as a post‐harvest treatment to control Alternaria rot in tomato fruit without detrimental effects on the tomato post‐harvest quality. Copyright © 2005 Society of Chemical Industry     

Alleviation of chilling injury in postharvest tomato fruit by preconditioning with ultraviolet irradiation

BACKGROUND: Tomato fruit is usually stored at low temperatures for delayed ripening and extended shelf life. However, tomato fruit is susceptible to chilling injury when exposed to low temperatures. In this study, the potential effects of preconditioning with UV‐C or UV‐B irradiation on chilling injury of postharvest tomato fruit were investigated. RESULTS: Mature–green tomato fruit were exposed to 4 kJ m^?2 UV‐C or 20 kJ m^?2 UV‐B irradiation and stored for 20 days at 2 °C and subsequently 10 days at 20 °C. UV irradiation was effective in reducing chilling injury index and delaying ethylene peak. Furthermore, UV irradiation preserved storage quality as manifested by reduced weight loss, better retention of firmness, and higher contents of total soluble solids, soluble protein and soluble sugar during subsequent storage at 20 °C. UV‐C irradiation significantly delayed the development of the red colour after 10 days of storage at 20 °C. On the other hand, UV irradiation decreased total phenolics content and antioxidant capacity, suggesting possibly reduced stress response to low temperature resulted from enhanced physiological adaptation by UV preconditioning. CONCLUSION: Our results suggest that preconditioning with UV‐C or UV‐B irradiation in appropriate doses had a positive effect on alleviating chilling injury in postharvest tomato fruit. Copyright © 2012 Society of Chemical Industry     

Effects of 1‐methylcyclopropene and gibberellic acid on ripening of Chinese jujube (Zizyphus jujuba M) in relation to quality

Overripening of Chinese jujube (Zizyphus jujuba M) fruit at the postharvest stage usually results in a dramatic decline in quality. The role of 1‐methylcyclopropene (1‐MCP) and gibberellic acid (GA) in fruit ripening of Chinese jujube during storage in relation to quality was investigated. Fruit ripening of jujube was significantly enhanced by ethylene, whereas rates of respiration and ethylene production of the fruit were reduced by 1‐MCP. Treatment with 1‐MCP or GA delayed the decreases in firmness and vitamin C and reduced the level of ethanol. Furthermore, the effectiveness of 1‐MCP was improved by replicate treatments during storage at 20 or 2 °C. In addition, treatment with GA + 1‐MCP resulted in additive beneficial effects on ripening inhibition of the fruit. Copyright © 2003 Society of Chemical Industry     

A combination of marine yeast and food additive enhances preventive effects on postharvest decay of jujubes (Zizyphus jujuba)

We investigated the effects of marine yeast Rhodosporidium paludigenum in combination with a food additive, carboxymethylcellulose sodium (CMC-Na), on prevention of postharvest decay and food quality of Chinese winter jujubes. R. paludigenum (1 × 10⁸ cells/ml) combined with CMC-Na (0.3%) significantly increased the inhibition of black rot on jujubes at 25 °C when compared with R. paludigenum-alone treatment (5.8% vs. 20%, p < 0.05). The combination also reduced natural rot from 86% (control) to 56%. The combination caused transient changes in enzyme activities or contents of some oxidation reactive markers such as peroxidase (POD), superoxide dismutase (SOD), and malondialdehyde (MDA) of jujubes. The combination had no significant effect on the food qualities such as colour (chroma and hue angle), total soluble solid (TSS) and titratable acidity (TA) of the fruit. While enhancing these effects, CMC-Na did not affect the survival of R. paludigenum in nutrient yeast dextrose agar (NYDA) culture. Thus, we conclude that the combination of R. paludigenum and CMC-Na is a promising formulation to control postharvest decay of Chinese winter jujubes.     

Use of UV-C treatments to maintain quality and extend the shelf life of green fresh-cut bell pepper (Capsicum annuum L.)

Abstract: The objective of this work was to select a Ultraviolet‐C (UV‐C) treatment for fresh‐cut mature green bell pepper, and to evaluate the effect of its combination with refrigeration on quality maintenance. Bell pepper sticks were treated with 0, 3, 10, or 20 kJ/m² UV‐C in the outer (O), inner (I), or both sides of the pericarp (I/O) and stored for 8 d at 10 °C. During the first 5 d of storage, all UV‐C treatments reduced deterioration as compared to the control. The treatment with 20 kJ/m² I/O was the most effective to reduce deterioration, and was used for further evaluations. In a second group of experiments, mature green bell pepper sticks were treated with 20 kJ/m² I/O, stored at 5 °C for 7 or 12 d and assessed for physical and chemical analysis, and microbiological quality. UV‐C‐treated fruit showed lower exudates and shriveling than the control. UV exposure also reduced decay, tissue damage, and electrolyte leakage. After 12 d at 5 °C, UV‐C irradiated peppers remained firmer and had higher resistance to deformation than the control. The UV‐C treatments also reduced weight loss and pectin solubilization. UV‐C exposure decreased the counts of mesophile bacteria and molds, and did not affect acidity or sugars. UV‐C‐treated fruit stored for 0 or 7 d at 5 °C did not show major differences in antioxidants from the control as measured against DPPH^? or ABTS^?+ radicals. Results suggest that UV‐C exposure is useful to maintain quality of refrigerated fresh‐cut green pepper. Practical Application: Exposure to UV‐C radiation before packing and refrigeration could be a useful nonchemical alternative to maintain quality and reduce postharvest losses in the fresh‐cut industry.     

5株枣果实采后病原真菌分离鉴定及rDNA ITS区序列分析

枣果实皮薄肉厚、细嫩多汁,不仅在采后运输中易损坏,也极易受微生物侵染而腐烂变质。对造成枣果实采后腐烂变质的病原真菌进行分离筛选,结合形态学观察、真菌rDNA内转录间隔区(internal transcribed spacer, ITS)的序列分析构建进化树,同时进行菌株的回接及病斑病症的验证,最终从采后贮藏过程中自然发病的冬枣和骏枣果实上分别分离到3株(221~#、227~#、232~#)和2株(229~#和230~#)丝状病原真菌。经形态学初步鉴定菌株221~#和227~#为镰孢菌,229~#和232~#为葡柄霉,230~#为短柄霉属真菌,通过rDNA ITS区序列分析,鉴定221~#为木贼镰孢菌(Fusarium equiseti),227~#为变红镰孢菌(Fusarium incarnatum),229~#为番茄匍柄霉(Stemphylium lycopersici),230~#为产酶短梗霉(Aureobasidium proteae),232~#为葡柄霉(Stemphylium armeriae)。目前这5种病原真菌均未发现可导致枣果实采后病害发生的报道,其中Stemphyli...     

Effect of yeast antagonist in combination with heat treatment on postharvest blue mold decay and Rhizopus decay of peaches

The potential of using heat treatment alone or in combination with an antagonistic yeast for the control of blue mold decay and Rhizopus decay of peaches caused by Penicillium expansum and Rhizopus stolonifer respectively, and in reducing natural decay development of peach fruits, as well as its effects on postharvest quality of fruit was investigated. In vitro tests, spore germination of pathogens in PDB was greatly controlled by the heat treatment of 37 degrees C for 2 d. In vivo test to control blue mold decay of peaches, heat treatment and antagonist yeast, as stand-alone treatments, were capable of reducing the percentage of infected wounds from 92.5% to 52.5% and 62.5%, respectively, when peach fruits stored at 25 degrees C for 6 d. However, in fruit treated with combination of heat treatment and Cryptococcus laurentii, the percentage of infected wounds of blue mold decay was only 22.5%. The test of using heat treatment alone or in combination with C. laurentii to control Rhizopus decay of peaches gave a similar result. The application of heat treatment and C. laurentii resulted in low average natural decay incidences on peaches after storage at 4 degrees C for 30 days and 20 degrees C for 7 days ranging from 40% to 30%, compared with 20% in the control fruit. The combination of heat treatment and C. laurentii was the most effective treatment, and the percentage of decayed fruits was 20%. Heat treatment in combination with C. laurentii had no significant effect on firmness, TSS, ascorbic acid or titratable acidity compared to control fruit. Thus, the combination of heat treatment and C. laurentii could be an alternative to chemicals for the control of postharvest decay on peach fruits.     

Integrated control of postharvest diseases of pear fruits using antagonistic yeasts in combination with ammonium molybdate

The effect of ammonium molybdate (NH₄Mo) as an additive to improve biocontrol efficacy of antagonistic yeasts Rhodotorula glutinis and Trichosporon sp. against blue mold and Alternaria rot of pear fruits caused by Penicillium expansum and Alternaria alternata, respectively, was evaluated. Biocontrol activity of R. glutinis was enhanced in combination with NH₄Mo, whereas the efficacy of Trichosporon sp. was not improved. Combining R. glutinis with 1 mmol l^?1 NH₄Mo provided a more effective control on P. expansum and A. alternata than applying the yeast or NH₄Mo alone. Addition of 1 mmol l^?1 NH₄Mo significantly affected the growth of R. glutinis and Trichosporon sp. in nutrient yeast dextrose broth medium, but did not affect the growth of R. glutinis and Trichosporon sp. in pear wounds. Thus, it appears that the use of NH₄Mo is a useful approach to improve the efficacy of R. glutinis for postharvest disease control. Copyright © 2005 Society of Chemical Industry     

Fate of Escherichia coli in apple and reduction of its growth using the postharvest biocontrol agent Candida sake CPA‐1

BACKGROUND: Generally, acidic fruits and fruit juices are considered ‘safe’ from a microbiological point of view. However, some outbreaks of foodborne illnesses have been linked to the consumption of unpasteurised cider. The aim of this work was to study the survival of Escherichia coli in apple juice, wounds and flesh and on apple surfaces at different temperatures and to determine the effect of the fungal biocontrol agent Candida sake CPA‐1 against the colonisation of apple by E. coli. RESULTS: Trials were conducted with a mixture of five strains of E. coli isolated from apples. E. coli was unable to grow in apple juice at 5, 15 and 25 °C but survived. At 10 °C and above, E. coli thrived in fresh‐cut apple and wounds. At 5 °C it survived in apple wounds after 27 days of storage and after 21 days in fresh‐cut apples. When E. coli was inoculated in apple wounds together with the yeast antagonist C. sake, its growth was reduced by approximately 1 log cfu wound^?1 at 25 °C. At 5 °C no effect of the biocontrol agent was observed. CONCLUSION: Despite the low pH of apple, a rapid increase in the bacterial population is possible if the temperature is not kept low enough. The biocontrol agent C. sake, developed to prevent fruit decay during storage, could also reduce E. coli growth in wounded apples at abusive temperatures. This would represent an additional benefit of using this biocontrol agent when applied to control postharvest diseases. Copyright © 2009 Society of Chemical Industry     

Effects of 1-methylcyclopropene(1-MCP) on ripening and resistance of jujube (Zizyphus jujuba cv. Huping) fruit against postharvest disease

The effects of 1-methylcyclopropene (1-MCP) on senescence and induction of resistance against postharvest decay in jujube (Zizyphus jujuba cv. Huping) fruit were investigated in this study. The results indicated that, compared to control, 1-MCP at 1 μL L^?l depressed ethylene production by 28% and respiration rate by 30% at 24 h after treatment, resulting in effective delay in fruit senescence. 1-MCP treatment was beneficial for maintaining quality of jujube fruit stored both at 25 and 0 °C, retarding decline of firmness, vitamin C, titratable acidity (TA) and soluble solids content (SSC) which are important parameters for fruit quality evaluation during the storage periods. Moreover, 1-MCP effectively limited the development of lesion diameter of blue mold rot and significantly reduced the incidence of natural decay. The activities of phenylalanine ammonia-lyase (PAL), polyphenol oxidase (PPO), catalase (CAT) and superoxide dismutase (SOD) were significantly induced after 1-MCP treatment. These findings indicate that the induced resistance in jujube fruit by 1-MCP is related with the increase of enzymes involved in scavenging of reactive oxygen species and enzymes associated with phenolics metabolism which produces highly toxic products against pathogen invasion. Our results suggest that 1-MCP has potential effect on maintaining the quality and extending postharvest life of jujube fruit.     

Yeasts associated with plums and their potential for controlling brown rot after harvest

Bacterial and yeast antagonists isolated from fruit surfaces have been effective in controlling various post‐harvest diseases, and several microbial antagonists have been developed into commercial products. Our knowledge of the fruit microbial community, with the exception of grapes, apples and some citrus fruit, is rudimentary and the potential of the resident yeasts for biocontrol remains largely unknown. We determined the occurrence of yeasts on plum surfaces during fruit development from the pre‐hardening stage until harvest for 2 years. A total of 16 species from 13 genera were isolated. Species from three genera, basidiomycetes Rhodotorula (29.5%) and Sporidiobolus (24.7%) and the dimorphic ascomycete genus Aureobasidium (24.7%), constituted 78.7% of all isolations and were recovered throughout fruit development, while Cryptococcus spp. constituted only 6.2% of the total plum isolates. The yeast community in the final sampling was significantly different from the first three samplings, reflecting a rapidly changing fruit habitat during the maturation of fruit. For example, Hanseniaspora, Pichia, Zygosaccharomyces and Wickerhamomyces occurred only on the most mature fruit. Screening of the yeasts for antagonistic activity against Monilinia fructicola, a fungus that causes brown rot, revealed a range of biocontrol activities. Several isolates provided complete control of the decay on plums, challenged with a pathogen suspension of 10³ conidia/ml and > 90% of control on fruit inoculated with the pathogen at a concentration 10 times higher. Some of the best antagonists included A. pullulans and R. phylloplana. Populations of both of these antagonists increased rapidly by several orders of magnitude in wounds of plums incubated at 24ºC and 4ºC. Our results indicate that plum surfaces harbour several yeast species, with excellent potential for use in biological control of brown rot of stone fruits. Published 2014. This article is a U.S. Government work and is in the public domain in the USA     

The preservation effect of <Emphasis Type="Italic">Metschnikowia pulcherrima</Emphasis> yeast on anthracnose of postharvest mango fruits and the possible mechanism

This study aimed to determine the effects of Metschnikowia pulcherrima yeast on storage quality of ‘Tainong’ mango, and elucidate it’s possible anti–disease mechanism. The results showed that M. pulcherrima could inhibit the changes in peel colour, fruit firmness, the contents of total soluble solids, total acid and vitamin C, and maintain the storage quality of mango fruits. An investigation of the mechanism showed that M. pulcherrima competed not only for the primary carbon source, but also for living space with Colletotrichum gloeosporioides. In addition, M. pulcherrima promoted the activities of defence-related enzymes, including ß-1,3-glucanase(GLU) and chitinase (CHT), and secreted a small amount of antimicrobial substances composed of volatile and nonvolatile anti-fungal compounds. The results strongly demonstrated that antagonistic yeast M. pulcherrima could be applied as a biocontrol agent for deducing the spoilage and decay of mango fruit.     

精氨酸处理对采后冬枣黑斑病的抗病作用

为研究精氨酸（Arginine,Arg）处理对采后冬枣果实抗病性的影响,用不同浓度的Arg溶液（0、20、200、1000 μmol/L）浸泡枣果实,再对处理后的枣果实进行互隔交链孢（Alternaria alternata）接种,测定贮藏期间病斑直径、抗病相关酶的活性以及黄酮、多酚、木质素的含量。结果表明,Arg处理可以显著减缓冬枣接种A.alternata后病斑直径的扩展,进一步研究表明Arg处理能诱导其苯丙氨酸解氨酶（phenylalamineammonialyase,PAL）、过氧化物酶（peroxidase,POD）、β-1,3-葡聚糖酶（β-1,3-glucanase,GLU）、几丁质酶（chitinase,CHI）活性的上升,其中200 μmol/L Arg处理的抗病相关酶活性最高。同时,Arg处理能提高枣果实中黄酮、多酚和木质素的含量,且200 μmol/L Arg处理组的黄酮、多酚和木质素含量最高。由此表明,Arg处理通过提高抗病相关蛋白酶（PAL、POD、GLU、CHI）的活性以及黄酮、多酚、木质素的含量来增强采后冬枣果实的抗病能力,有望成为一种新的防腐保鲜剂应用于冬枣果实的防腐保鲜。     

Combined treatments of chitosan and sodium silicate to inhibit Alternaria alternata pathogens of postharvest winter jujube

Alternaria alternata is a pathogenic fungus that infects jujube fruit and leads to serious economic losses. In this paper, the antifungal activity of chitosan combined with sodium silicate against A. alternata in vitro and in vivo was investigated, and the possible antimicrobial mechanisms were explored. Results showed that the spore germination and colony expansion of A. alternata were significantly inhibited by chitosan. Chitosan treatment induced the leakages of intercellular electrolytes, nucleic acids, and soluble protein of A. alternata. Meanwhile, chitosan damaged the cell morphology and membrane integrity of A. alternata. The combination of chitosan and sodium silicate was more effective than chitosan alone. In addition, the effect of chitosan and sodium silicate could significantly decrease natural rot rate and delay lesion expansion of winter jujube. Collectively, chitosan combined with sodium silicate had the potential to control postharvest diseases of fruit caused by A. alternata.     

Salicylic acid enhances biocontrol efficacy of Rhodotorula glutinis against postharvest Rhizopus rot of strawberries and the possible mechanisms involved

The potential of using Rhodotorula glutinis alone or in combination with salicylic acid (SA) for the control of postharvest Rhizopus rot of strawberries, and their effects on enzyme activities of fruits were investigated. The combination of R. glutinis (1 × 10⁸ CFU ml⁻¹) with SA (100 μg ml⁻¹) resulted in a significant reduction in the disease incidence and lesion diameter of Rhizopus rot on the strawberry fruits at 20 °C and 4 °C, and more so than with SA or yeast alone. SA at the concentration of 100–1000 μg ml⁻¹ significantly inhibited spore germination of Rhizopus stolonifer. About 100 μg ml⁻¹ of SA did not inhibit the growth of the antagonistic yeast, and could significantly increase the population growth of R. glutinis in strawberry wounds at 20 °C. SA, combined with R. glutinis, increased the activity of strawberry host defence enzymes (POD) and cell wall lytic enzymes (β-1,3-glucanase).     

Biological control of Penicillium italicum of Citrus and Botrytis cinerea of Grape by Strain 34–9 of Kloeckera apiculata

The biological control capability of strain 34-9 of Kloeckera apiculata against Penicillium italium (Wehmer), postharvest rot of citrus fruits and Botrytis cinerea, postharvest rot of grape fruits was studied in vitro and in vivo. Strain 34-9 of K. apiculata at 3×10⁸ CFU (colony-forming unit)/ml of washed cells provided complete control of 3×10⁵ spores/ml of P. italium and B. cinerea during storage at 25 °C for 6 d. Antagonist population increased 40, 195 times in citrus fruit wound site and grape fruit wound site at 25 °C for 3 d, respectively, then the population stabilized for the remaining storage period. Cell-free culture filtrate, supernatant fluid and sterilized solution of strain 34-9 of K. apiculata had no antagonist against P. italium of citrus and B. cinerea of grape. These results showed that competition for nutrient, not antibiotic production, played a major role in the biological control capability of strain 34-9 of K. apiculata against P. italium of citrus and B. cinerea of grape.