【作者】 黄娇；

【导师】 朱天辉；

【作者基本信息】 四川农业大学 ， 园林植物与观赏园艺， 2006， 硕士

【摘要】 本研究以植物微生态学原理为基础，分析香石竹切花的附生微生物区系及对衰老的影响，并对切花的生物保鲜及衰老生理进行有益的探讨，以期找到适合香石竹切花保鲜的微生物种类及生物制剂，其主要研究结果如下： 1、探讨了香石竹切花茎切口微生物对切花衰老的影响。经香石竹切花采后茎切口的微生物分离培养，发现香石竹切花采后瓶插时的微生物影响主要以细菌为主，真菌未检出，从30株香石竹切花上共分离得32个细菌菌株。通过人工回接实验，分别对接种不同细菌菌株的瓶插香石竹切花进行外观形态指标及瓶插寿命的观测，结果表明：不同菌株处理下香石竹切花的萎蔫程度，外观形态，花径变化以及瓶插寿命存在明显差异，有6株细菌对香石竹切花采后萎蔫影响较严重，有2株属于益生菌，其余菌株无影响。经细菌性状初步鉴定，香石竹切花采后病原菌为植物棒形杆菌Clavibacter。 2、初步分析了同一生态条件下香石竹切花叶片和花瓣的附生细菌类群，通过两种方法平板分离培养，从香石竹切花叶和花共分离纯化出33个细菌菌株，其中13株为芽孢杆菌。从已获得的13株芽孢杆菌中，通过提取其代谢液（5％）瓶插切花，初步筛选出对切花保鲜有益的芽孢杆菌B₀₁、B₀₂、B₀₅，处理的瓶插寿命均低于对照。再通过B₀₁、B₀₂、B₀₅不同浓度代谢液（0.5％、1％、2％、5％）对切花保鲜试验的比较分析，筛选出B₀₂（经鉴定为Bacillus Cereus）作为本实验的有益菌。三种芽孢杆菌低浓度的代谢液（0.5％）能延长切花瓶插寿命，增大切花最大花径，促进切花吸水，切花鲜样质量增加，观赏效果提高，其中以B₀₂低浓度代谢液（0.5％）的效果最好，B₀₁次之，B₀₅相对较差；但其高浓度下对切花保鲜有负效果，具体机理尚待进一步研究。B₀₂代谢液保鲜效果与环境的关系测定结果表明，香石竹切花瓶插寿命与温度成负相关，与相对湿度成正相关。 3、研究了芽孢杆菌B₀₂代谢液对瓶插香石竹切花衰老生理的影响及其保鲜机制。试验结果表明，低浓度的B₀₂代谢液（0.5％）能延长切花寿命，增大切花最大花径，保持切花鲜样质量，降低细胞膜相对透性，提高观赏效果；明显提高SOD和CAT活性，SOD酶活性提高37.4％，有效减少可溶性蛋白质和可溶性糖降解，延缓衰老。B₀₂代谢液对切花萎蔫病原菌Clavibacter不具拮抗性，B₀₂代谢液能产生IAA、GA₃、ZT等植物激素及外源SOD酶是其能对香石竹切花进行保鲜的主要机制，推测5％代更多还原

【Abstract】 The study is based on the theory of Plant Microecology, the epiphytic microflora of cut carnation and the effects of microoganism to senescence were studied, the biological preservation and the physiology of senescence of cut carnation were explored instructively in this paper, and the species of microorganism and biological preparation which can preserve to cut carnation were expected to obtain. The main results are as follows:1 、This paper reported the effects of microorganism on the tangent plane of stem to senescence in cut carnation during postharvest life. The culture analysis of vase water and tangent plane of stem showed that bacterium was main microorganism in cut carnation during its postharvest life, a total of 32 bacterial isolates were obtained from 30 cut carnation. The different inoculation of bacteria were investigated on flowering status index. The results indicated that the differences of withering degree, flower diameter and vase life among different cut carnation treatment were significant, and six isolates of 32 strains were effective, two isolates were beneficial. The pathogenic bacteria were identified as Clavibacter.2、The primary analysis on the epiphytic bacterium of cut carnation leaf and petal in the same condition were reported, a total of 33 bacterial isolates were obtained from cut carnation leaf and petal by two agar plate culture, among which 13 bacterial strain were identified as Bacillus spp. The metabolites vase solution(5%) of 13 Bacillus strains were investigated on flowering status index, the treated vase life were lower than the contrast,更多还原