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期 刊 ：植物保护学报 2009年

关键词：枣疯病植原体；野生酸枣；抗病品种；嫁接繁殖；分子检测与鉴定；

Keywords:jujube witches’broom phytoplasma, wild sour jujube (Zizyphus spinosa), resistant Chinese jujube cultivar, graft propagation, molecular detection and identification,

摘 要 ：为了明确野生酸枣疯病与栽培大枣疯病发生和流行的关系,采用随机徒步调查、挖根和接穗嫁接法对我国野生酸枣、栽培大枣及大枣接穗嫁接野生酸枣的枣疯病进行了田间调查,并取样检测病菌及比较不同菌株的保守基因序列。结果显示,我国野生酸枣疯病发生范围广,且地区间自然发病率差异很大,在0~40%之间;病株呈明显的团簇状分布,病菌在团簇中的根蘖苗与母株间传播或通过介体昆虫传播到后代种子苗上。在枣疯病流行区,栽培大枣发病与枣园周围分布的野生酸枣发病程度有关;用感病品系的接穗或带菌接穗嫁接到野生酸枣砧木上易导致嫁接苗发病和病害流行,而采用抗病的壶瓶枣和婆枣抗病品系接穗嫁接野生酸枣则发病率明显下降。用巢式PCR进行的病菌检测结果显示,在病害流行区酸枣或大枣无症状枝叶样品的带菌检出率为10%~32%。不同地区栽培大枣和野生酸枣上植原体的16S rDNA、16S-23S rDNA间区(SR)及核糖体蛋白基因(rp)序列比较鉴定结果显示,侵染酸枣的植原体与栽培大枣疯病植原体应为相互传染的同种致病菌。

Abstract:To determine the relatedness of infected wild sour jujube Zizyphus spinosa Hu by phytoplasma with occurrence and epidemic of cultivated Chinese jujube Zizyphus jujuba Mill witches’ broom disease, the field survey, phytoplasmal detection and molecular characterization based on the conserved genes in jujube witches’ broom-occurring regions growing with wild sour jujubes, cultivated Chinese jujubes as well as grafted jujubes between wild sour and cultivated jujubes were carried out in China. The results showed that there existed a wide distribution of wild sour jujube witches’ broom disease and the disease incidences ranged from 0-40% in different regions of China. And the diseased wild sour jujubes distributed frequently in cluster, resulting from the transmission either through root sprouting or offspring seed-borne seedlings by insect vector. In jujube witches’ broom prevailing regions, the infected wild sour jujubes were generally contributed to the severity of the disease occurrence of nearby Chinese jujube orchards. The propagation way by grafting susceptible cultivated scions or phytoplasma-carrying Chinese jujube scions onto the wild jujube stocks standing in the field mostly was more likely to result in the occurrence and epidemic of newly-developed jujube orchard, whereas the application of resistant cultivars or lines such as cv. Hupingzao and JL24 of cv. Pozao could lead to the reduction of disease rate. The nested-PCR detection of phytoplasma indicated that the percentages of symptomless phytoplasma-carrying trees surrounding diseased ones were 10% to 32%. Comparative molecular analyses to the 16S rDNA, 16S-23S rDNA (SR), and ribosome protein gene (rp) sequences of phytoplasmas infecting both wild sour and Chinese jujubes showed that the phytoplasma infecting wild sour jujubes was identical to the one from the cultivated Chinese jujubes of different geographic regions.

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