中文摘要：

用含有GFP基因标记的内生细菌菌株BS-2-gfp和TB2-gfp,采用喷雾接种的方法,研究其在荔枝叶片、花、幼果及成熟果实果皮内的定殖动态及其与防病保鲜之间的关系.结果表明：内生细菌BS-2-gfp和TB2-gfp能在荔枝叶片、花、幼果及采后果皮上定殖,能在各组织内繁殖并可在花和幼果间传导.内生细菌在荔枝叶片上的定殖因季节和荔枝生长期的不同而异,与秋季相比,春季定殖期限长,定殖量大.内生细菌在荔枝不同部位的定殖时间和定殖量也不同,在叶片上接种37d后还可分离回收到接种的2种目标细菌,在花上接种10d后就回收不到BS-2-gfp,而成熟荔枝果皮上2种菌的定殖量最大.防病试验表明,当荔枝霜疫病的病情指数急剧上升时,TB2-gfp在荔枝果皮的定殖量达到最大,为1.90×106CFU.g-1FM;保鲜试验发现,TB2-gfp菌株的保鲜效果优于BS-2-gfp,菌株在荔枝果皮内的定殖量也高于菌株BS-2-gfp,表明供试内生细菌在荔枝果皮的定殖量与其防病及保鲜效果呈正相关.

英文摘要：

By spraying the GFP-marked endophytic bacterial strains BS-2-gfp and TB2-gfp,this paper studied their colonization in lychee organs and the functions of the strains in disease control and fruit preservation.The BS-2-gfp and TB2-gfp could colonize and propagate in lychee leaves,flowers,un-matured fruits,and matured fruits,and transfer from the flowers to un-matured fruits.The colonization of BS-2-gfp and TB2-gfp in lychee leaves varied with season and growth stage,being larger in quantity and longer in duration in spring than in autumn.The colonization quantity and duration of the strains also differed in other organs.Both the BS-2-gfp and the TB2-gfp could be isolated and recovered from lychee leaves after 37 d inoculation,the BS-2-gfp could not be isolated from the flowers after inoculation for 10 d,and the BS-2-gfp and TB2-gfp had the largest colonization quantity in matured fruits.The colonization quantity of TB2-gfp in lychee pericarp reached to the maximum（1.90×106 CFU·g-1FM） when the disease index of litchi downy blight had a sharp increase,and,compared with BS-2-gfp,the TB2-gfp had better fruit preservation efficiency,and its colonization quantity in lychee pericarp was also higher.It was suggested that there was a positive correlation between the colonization quantity of test bacterial strains in lychee pericarp and the disease control and fruit preservation effect.