柑橘酸腐病拮抗菌的筛选及其对柑橘品质的影响

Screening of Antagonistic Bacillus of Citrus Sour Rot and Its Effects on the Quality of Citrus

[目的]筛选一株柑橘酸腐病拮抗菌,用于柑橘采后酸腐病的防治。[方法]筛选一株对柑橘酸腐病具有高效拮抗作用的生防菌,并研究其对柑橘可溶性固形物、可滴定酸、抗坏血酸及挥发性物质含量的影响。[结果]筛选出的拮抗菌株在平板上对白地霉(Geotrichum candidum Link)的抑菌率为82.58%。当柑橘酸腐病发病率为96.67%时,接种10~8 CFU/mL生防菌能有效降低柑橘酸腐病发病率至13.89%。经鉴定发现拮抗菌为解淀粉芽孢杆菌植物亚种(Bacillus amyloliqufaciens subsp.plantarum),其能延缓柑橘贮藏过程中抗坏血酸含量的下降,保持柑橘果实中可溶性固形物和可滴定酸的含量,延缓果实衰老,提高多种香味物质,特别是柠檬烯、月桂烯、沉香醇及奎醛等的含量,同时延缓正己醛和反式-2-己烯醛等挥发性物质的降解,从而有效延长柑橘的贮藏期,保证柑橘贮藏期内良好的果实风味、食品品质和营养价值。[结论]该研究可推动柑橘采后生物保鲜产业的发展。

[Objective]To screen out a strain of antagonistic bacillus of citrus sour rot for the prevention and control of citrus sour rot after harvest.[Method]A strain of biocontrol bacteria with highly antagonistic effect on citrus sour rot was screened out,and itseffectson the contentsof soluble solid,titratable acid,ascorbic acid and volatiles in citrus were studied.[Result]The inhibition rate of screened antagonistic bacillus on Geotrichum candidum Link was 82.58%.The morbidity of sour rot decreased from 96.67% to about13.98% when the biocontrol bacillus’s innoculation amount was10 8 CFU/mL.The antagonistic bacillus was identified as Bacillus amyloliqufaciens subsp. plantarum,which could prolong the decrease of ascorbic acid content,maintain the content of soluble solid and titratabe acid in the storage period,delaying the fruits’ aging,increase the content of multiple flavor compounds,especially limonene,yrcene,linalool and kratos aldehyde,and reduce the degradation of some volatiles that could inhibit the propagation of pathogenic bacteria,such as hexanal,trans-2-hexenal,and so on.Furthermore,it could effectively prolong the storage period of citrus,and ensure good fruit flavor,food quality and nutritional value during the storage period of citrus.[Conclusion]The research could promote the development of citrus postharvest biological preservation industry.