作 者：
陈声祥;阮义理;金登迪;林瑞芬;陈光堉;高东明
摘 要：
我国水稻黄矮病,是六十年代以来新发现的一种病毒病,目前分布范围广,一般发病损失产量2-3成,是南方稻区的一个重要病害。本病的症状特征是:始病叶位,在水稻生长前期,从顶叶以下一、二叶开始;病斑先从叶尖端开始向叶基扩展,全叶形成叶肉黄化、叶脉绿色的条状或斑驳状花叶,以后向上纵卷枯黄;病叶与茎杆夹角增大。病原为弹状病毒,在病叶超薄切片中大小为50-90×100-180nm,在分离提纯过程中容易发生变化。介体昆虫有三种黑尾叶蝉,病毒在虫体内属非经卵传染。黑尾叶蝉(Nepho-teffix cincticeps)获毒的最短时间为5-10分钟,多数12小时以上,循回期7-39天(随自然气温的上升而缩拉),传毒时间至少3-5分钟,开始传毒虫态最早是4龄,多数在成虫期,无毒虫时病毒的亲和性个体在半数以下,保毒虫传毒多数是不连续的,有效的传毒天率(传毒天数与昆虫自开始传毒到死亡的天数之比)在30-60%。单个虫体可以同时获得本病和普通矮缩病或黄萎病(类菌质体)两种病原,并能先后或同叶在一株水稻上传病。病毒寄主目前仅知水稻(Oriza sativa)一种。水稻对病毒的反应因品种、生育期和环境条件不同而异。抗性品种主要表现为感病率低,潜育期长,病情较轻,病株恢复率高等。水稻在分蘖末期以前为感病期,分蘖初期至盛期最感病,拔节以后不易感病。发病生育期迟,生长条件好时病株恢复率高,产量损失少。浙江省双季稻区,病毒主要在黑尾叶蝉体内越冬,春季随介体昆虫的迁飞传播到水稻上,成为初次侵染源。早稻发病主要由初次侵染源引起,晚稻发病则主要由早稻收获期迁移的介体昆虫侵染所致。早稻后期发病率与苗期迁入的越冬代黑尾叶蝉虫量成正相关,晚稻后期发病率与本田初期(约15天内)迁入的第二、三代虫量成正相关。
译 名：
STUDIES ON THE DEVOLOPMENT AND EPIPHYTOTRIS OF THE RICE YELLOW STUNT DISEASE
作 者：
Chen, S. X. Yuan, Y. L. King, D. D. Chen, K. Y. Lin, R. T. Kao, T. M.(Chekiang Academy of Agricultural Science, Hangchow)
摘 要：
The rice yellow stunt in sonth & east China, was widly distributed andcaused a loss amounts to 20-30% of the crop.The main symptoms of the dise-ase consists of yellowing in the second or third youngest leaf of the plantmottling stripe of the interveinal area of leaves later. Diseased leaves formwider angles with the stem. The pathogen is a bullet-shaped virus, with parti-cle size ranging 100-180×50-90 nm, shown in ultra-thin sections. Three speciesof the rice green leafhoppers (Nephotettix cincticeps N. nigropictus and N.vire-scens) have been shown to be vectors of the disease.The virus persists in thevectors but not by transovarial passage.The shortest acquisition period for therice green leafhopper, Nephotettix cincticeps, is 5-10 minutes, although withmost individuals over 12 hours are needed. Incubation period is found to be 7-39 days (the period could be shortened with rise of temperature).Inoculationfeeding period requires a minimum of 3-5 minutes. The 4th nymphal stage is theearliest stage known for initial transmission, while with most individuals tran-smission occurs at the adult stage. Active transmitters constitute less than 50%of the group given acquisition feeding. Infective insects generally are of theintermittent transmission type, the rate of effective transmission days 30-60%.An individual insect might acquire this virus and at the same time took upeither rice dwarf virus or the pathogen of the yellow stunt, and may transmitone disease after another or both simultaneously to the rice plants.Rice (Oryzasativa) is the only known host of this virus, The most susceptible period ofthe rice plants is at the middle part of tillering stage. When the disease occurson the later maturitation period, the recovery rate of diseased plants was high.In regions of Chekiang province where 2 consecutive crops of rice are practiced, the overwintering rice green leafhoppers is serve as the primary source of inf-ection.In the later autumn crop, the disease prevalence is directly correlatedwith the amount of immigrating vectors of the 2nd and 3rd generations.
