【摘要】 针对月季栽培过程中出现的最严重的根结线虫病防治问题 ,开展了月季对根结线虫抗性遗传研究。研究结果如下 :①对常用的 4种月季砧木R .multifloraK1 ,K2 ,CE63及R .indica对 4种常见根结线虫即南方根结线虫 (Meloidogyneincognita)、爪哇根结线虫 (M .javanica)、花生根结线虫 (M .arenaria)及北方根结线虫 (M .hapla)的抗性进行了测定 ,得出只有北方根结线虫能侵染月季 ,其余 3种不能侵染。②根结指数与对数转化后的每克根中雌虫数、雄虫数、3～ 4龄幼虫数之和、2龄幼虫数、卵数、成虫及 3～ 4龄幼虫数之总和、2龄幼虫与卵数之总和均呈线性相关关系 ,因此根结指数是进行抗性评价的可靠、简单及实用的指标。抗性划分标准如下 :根结指数 0 .0～ 1 .0 ,抗病 ;1 .0～ 2 .0 ,中等抗病 ;2 .0～ 3.0 ,感病 ;3.0～4.0 ,比较感病 ;4.0～ 5 .0 ,高度感病。③以根结指数为指标 ,通过对杂交所得 74个子代的抗性评价试验表明 :在 2抗性亲本所得 1 2个子代中 ,各子代抗性水平存在抗性分化 ,说明抗病基因不是由单一显性基因控制 ;在所有的 62个抗性亲本与感病亲本的杂交子代中 ,5 9个子代均比抗病亲本感病 ,表明抗病基因由隐性基因控制。因此 ,提出了月季对根结线虫的抗性遗传可能由 2个基因决定更多还原

【Abstract】 Firstly, the host suitability of four rose rootstocks from the INRA collection in Fréjus( France) ranging into three R. multiflora (designated as ’K1’, ’K2’ and ’CE63’) and one R. indica designated as ’Maroc’ was evaluated under greenhouse conditions using one population of each of the root knot nematodes (RKN) Meloidogyne arenaria,M. incognita, M. javanica and M. hapla . All the rootstocks expressed a high resistance to the first three RKN species and expressed different host suitability to M. hapla . Then resistance evaluation was performed based on the gall index (GI) rating and the numbers of the different developmental stages of the nematode. The linear correlation between GI and the log 10 ( x +1) transformed numbers of each nematode developmental stage was highly significant in all tested progenies. Consequently, gall index ratings is a good criterion to express the resistance level of tested material. According to Student Newman Keuls multiple range test at P ≤0.05, resistance is classified by following gall index rating: 0.0～1.0, resistant; 1.0～2.0, intermediate resistant; 2.0～3.0 , intermediate host; 3.0～4.0, host; 4.0～5.0, excellent host. At last , the study on the natural resistance character of the self incompatible species R. multiflora to M. hapla was conducted using a diallel cross involving the above mentioned 4 parental clones. A total of 74 GI hybrids obtained from cuttings, rooted in the nursery and inoculated individually in containers ( 10 repeats per clone) were evaluated for their host suitability under a high and durable inoculum pressure of the nematode. Plant were harvested 5 months after inoculation for a 0～ 5 gall index rating (10 replicates per clone) completed with nematode numbers in the roots (6 replicates per clone). Results based on statistical analysis of gall index and the numbers of the different developmental stages of nematodes showed: 1) In the GI cross between R x R (K1×K2), there is segregation, which indicated that resistance is not controlled by one dominant gene; 2) 58 of GI hybrids between R×H (CE63×K1, CE63×K2, Maroc×K1 and Maroc×K2) were more galled and had highes nematode numbers than their resistant parents, which suggested that the resistance is controlled by a recessive gene. A preliminary genetic hypothesis based on two genes controlling rose resistance to M.hapla is proposed.更多还原