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根据試驗結果,初步認为柑桔黃龙病可借东方桔蚜传病,其指示植物为由力克檸檬、北京香檸檬和墨西哥来檬等1—2月龄的实生幼苗。在这些指示植物和蕉柑幼苗上,用东方桔蚜传病以及用嫁接法传病所引起的症状均相同:在由力克檸檬和蕉柑上表現矮化及梢叶黄化;在北京香檸檬和墨西哥来檬上表現矮化、明脉和“嵌紋”等。同时,在北京香檸檬上,以蚜传发病植株的組織,进行回接的試株和以广州及普宁县病株的組織进行嫁接的試株,有些发生木质部陷点及木质部陷紋的症状。根据这些特点,虽然不能肯定柑桔黄龙病与南美洲柑桔衰退病的病原病毒相同,但它們很可能屬于同一类病毒(却柑桔衰退病毒类)。此病在指示植物上的潛育期最短为27天。在11月气温較低时的潛育期长达二个月以上。5月分在网罩内气温高达42℃,发病試株在一周内消失症状并恢复生长,但試株移到树蔭下(气温降低到25°—30℃左右),一个月内症状又重新出現。
According to the test results, it is preliminarily believed that the citrus Huanglongbing can be transmitted by the Oriental Myzus persicae, indicating that the plants are 1-2-month-old seedlings of Lectra, Lemongrass and Lemons. In these indications plants and banana seedlings, the symptoms caused by the transmission of the disease and the grafting by the Oriental Myzus persicae were the same: dwarf and shoot leaf yellowing on lemons and banana fruits; And Mexico to dwarf lemon, Ming veins and “embedded” and so on. At the same time, in Beijing bergamot, aphids were distributed in the diseased plant tissues, the test-rewinding strains and the grafted plants in the diseased plants of Guangzhou and Puning were some strains of xylem traps and xylem traps. Based on these characteristics, although it is not certain that citrus yellow dragon’s disease is the same as the pathogenic virus of citrus recession in South America, it is likely that they belong to the same virus (but the citrus recessive virus). The disease in the indicator plants on the shortest incubation period of 27 days. The incubation period at low temperatures in November is more than two months. In May, the temperature in the grille was as high as 42 ° C. The test strain disappeared and resumed its growth within a week, but the test strain was moved to the shade (the temperature dropped to about 25 ° -30 ° C) and the symptom was resumed within a month appear.