柠檬形克勒克酵母对温州蜜柑“国庆一号”采后贮藏的防腐效果

Citrus unshiu “Guoqing No.1” was used as material for elucidating the effect of Kloeckera apiculata suspension post-harvest treatment on preventing fruit decay during storage period. The result showed that K. apiculata preparation of 2×106CFU/mL (CFU, cloning forming unit) significantly reduced the development of decay caused by green mold, blue mold and stem rot, showing the same effect of carbendazim treatment after storage period of 100 days, and the disease incidence was controlled under 1%. The antagonist population was between 3.5×105CFU/mL and 1.7×107CFU/mL in citrus fruit, and increased 1.7×107CFU/mL after 40 days storage, and then stabilized for the remaining storage period. After storage at 5℃ for 100 days, K. apiculata strain 34-9 did not alter any quality parameters of fruit. During storage, the change of relative electrical conductivity (REC) showed a coordinate tendency with malondlaldehyde (MDA) content, which kept continuously growing from the beginning to the end of the storage. In the storage period of 25 days, the REC value and MDA content of the treatments were all significantly lower than those of water treatment, but had no obvious difference from those of carbendazim treatment. K. apiculata strain 34-9 had no effect on the enzyme activity of super oxide dismutase (SOD), but significantly improved peroxidase (POD) activity after 100 day storage.     

微波诱变选育柑橘采后病害拮抗菌柠檬形克勒克酵母研究

采用微波辐照,对柠檬形克勒克酵母(Kloeckera apiculata)进行诱变处理,确立了辐照的最佳时间为 50 s.选育到1株拮抗柑橘青霉病抑菌活性提高16.90%、生物量提高6.96%的菌株W50-56;选育到1株拮抗柑橘绿霉病抑菌活性提高17.38%、生物量提高5.86%的菌株W50-47.所选育的菌株经多次传代,遗传性状十分稳定.     

紫外诱变改良柑橘采后病害拮抗菌柠檬形克勒克酵母研究

以柠檬形克勒克酵母(Kloeckera apiculata)为出发菌株, 采用紫外线(UV)、UV+LiCl等方法对其进行诱变改良。确定了处理的最佳剂量：紫外处理15 W 30 cm照射20 s, UV+LiCl处理UV照射20 s并在平板中加入LiCl 0.3% (W/V)。选育到一株生理特性有明显改善的变异菌株UV20-13, 果实试验中, 7 d后柑橘青、绿霉病的发病率分别比出发菌株降低25.56%和10.00%。生长动态测定和传代试验表明, 该菌株生长特性优于出发菌株, 连续传代10代, 该菌株没有出现退化、回复突变等, 在遗传上是稳定的。     

紫外诱变改良柑橘采后病害拮抗菌柠檬形克勒克酵母研究

以柠檬形克勒克酵母(Kloeckera apiculata)为出发菌株,采用紫外线(UV)、UV LiCl等方法对其进行诱变改良.确定了处理的最佳剂量:紫外处理15 W 30 cm照射20 s,UV LiCl处理UV照射20 s并在平板中加入LiCl 0.3%(W/V).选育到一株生理特性有明显改善的变异菌株UV20-13,果实试验中,7 d后柑橘青、绿霉病的发病率分别比出发菌株降低25.56%和10.00%.生长动态测定和传代试验表明,该菌株生长特性优于出发菌株,连续传代10代,该菌株没有出现退化、回复突变等,在遗传上是稳定的.     

柠檬形克勒克酵母对温州蜜柑“国庆一号”采后贮藏的防腐效果

本实验以温州蜜柑"国庆一号"为试材,研究了柠檬形克勒克酵母Kloeckera apiculata悬浮液处理对柑橘果实采后防腐保鲜效果及相关酶的影响.结果表明,贮藏100d后,2×106CFU/mL(CFC表示菌落形成单位)的酵母菌液能有效地抑制青霉、绿霉和蒂腐病等贮藏期病害的发生,柑橘果实的腐烂率控制在1%以下,效果显著高于清水对照,与多菌灵相当;柠檬形克勒克酵母在柑橘果皮上的数量在3.5×105CFU/mL-1.7×107CFU/mL之间,在贮藏40d后最大值达到1.7×107CFU/mL,随后保持在106CFU/mL左右,100d贮藏结束后,品质分析表明,柠檬形克勒克酵母处理对柑橘品质没有不良影响.在整个贮藏期细胞膜透性与丙二醛(MDA)含量变化相对应,均呈上升趋势,在贮藏25d左右时酵母菌液处理和多菌灵处理的细胞膜透性与MDA含量均显著低于清水对照,而前二者之间无差异.酵母菌液对超氧化物歧化酶(SOD)活性没有诱导作用,而在贮藏后100d左右对过氧化物酶(POD)活性有诱导作用.