柑桔木虱传递柑桔黄龙病的初步研究

柑桔木虱是柑桔黄龙病主要媒介昆虫。几年来的试验初步表明:无病植株上繁殖木虱成虫,在病树上吸毒20—30天以上就可传病。黄龙病病原在成虫体内约经20—30天循回期、带毒后木虱成虫,虫口密度大(20头/苗以上),吸食传毒1天即可发病;虫口密度小(1—5头/苗),吸食传毒7—14天也能传病。潜伏期一般2—8个月,个别株2年才发病,病梢于冬季回接,3—5个月后也表现出和虫传发病苗相同的斑驳状病症。

PRELIMINARY RESEARCH ON TRANSMISSION OF CITRUS YELLOW SHOOT DISEASE BY Diaphorina cirri Kuw

The transmission trials of citrus yellow shoot disease by Diaphorina citri Kuw. were made during the years of 1979-1984. The adults of psyllid, free of yellow shoot pathogen, were reared on healthy plants, and then they were allowed to feed a period of 20-30 days on the typical type of mottling leaves plants to acquire the pathogen. The latent period of the pathogens in the body of the psyllid is about 20-30 days. After acquisition, the psyllid can transmit the disease successfully on healthy seedling in one day, if insect population was 20 adults/seedling.When the number of adults was 1-5 per each test seedling,the pathogen can also be transmitted in 7-14 days. Infected plants showed yellow shoot symptoms in 2-8 months after transmission feeding.When the diseased shoots were used as scions and grafted onto the healthy rootstock(Sweet organge and Sunki), some of them showed symptoms in 3-5 months. The symptoms of infected plants through both psyllids transmission and grafted inoculation were similar.