Study On Identification And Biological Characters Of Lanzhou Lily Wilt Pathogen

Lanzhou lily is the variety of perennial herb, which comes from Lilium davidii,which is only lived in the northeast two mountains area of the height 1800-2500 m.It is high nutritiona and taste sweet and fragrant that is the only edible sweet lily in China, the valuable edible, medicinal and ornamental of treasures of vegetables and also is a specialty of Gansu provice.The plant of lanzhou lily drives the development of local economy.But Lanzhou lily wilt is seriously impact economy income, production and cultivation, so that the sustainable development of lanzhou lily industry faced severe challenges of recent years in Lintao county, Shangying village.At present, there are no reports about research on Lanzhou Lily wilt.In this paper, we choose the wilt Lanzhou Lily in Shangying located in Gansu province as the research object. In order to provide a theroretical basis for further determining pathogen and living environment to the Lanzhou Lily wilt.We make researches about the fusarium wilt pathogen and the biological characteristics of the pathogen.And the main results are as follows:1、According to the investingations in May 2015,there are a majority of Lanzhou Lily wilt in the main planting areas in Shangying town in Lintao.The lily fresh root and basic dish turn brown rot at the early period of disease, the bulbs grow brown disease spot and gradually rot by turning deep brown and result in bulbs scatter from basic dish.The disease plant obviously reduce the height of growing, the suffering leaves turn yellow and special sample, like kraft paper, and gradually wilt from bellow and even die.2、Samples showing symptoms of wilt were collected from Lanzhou Lily bulbs and pathogenic soil of this area. A total of 5 Fusarium isolates that 4 species(F1,F2,F3,F4) isolated from Lanzhou Lily bulbs and one(F5) from soil were identified based on methods of isolation, purification, morphological characters and pathogenicity. The results indicated that the disease incidences reached 100% and the disease indexes of five pathogens were 85.42, 80.83, 75.83, 64.58 and 82.08 by bulbs stabbed vaccination Fusarium. Respectively, the disease incidences of the bulbs not stabbed vaccination Fusarium representing 85.71%, 47.62%, 42.86%, 19.05%, 57.14% and the disease indexes of five pathogens were 53.57, 22.62, 21.43, 9.52 and 25.00. Morphological characters results showed that strains F1, F2, F3, F4 and F5 were respectively identified as F. oxysporum, F. solani, F. tricinctum, F. tabacinum and F. graminearum.3、Researchs on morphological feature of Fusarium.oxysporum:Fusarium.oxysporum grow fastest on potassium nitrate as the nitrogen source, the diameter of the colonies reaches 4.87 cm after days, and it produces most spores on ammonium nitrate,followed by potassium nitrate, about 0.82×106cfu/ml,0.37×106cfu/ml after 7 days; The pathogen optimal carbon sources were sucrose. Stopped to grow when 40℃,the mycelia growing optimum temperature was 30℃.4、Researchs on morphological feature of Fusarium. solani :Mycelia of the pathogen Fusarium. solani grow optimal nitrogen source was potassium nitrate,reachs 3.5cm, it produces most spores on urea, about 1.82×106cfu/ml,followed by potassium nitrate,about 1.37×106cfu/ml.The pathogen optimal carbon sources were sucrose. Mycelial growth of PH range of 4~8, the optimal p H was 8.5、 Researchs on morphological feature of Fusarium.graminearum: Mycelia of the pathogen Fusarium. graminearum optimal nitrogen source was ammonium nitrate, followed by potassium nitrate, about 3.31 cm, 2.92 cm,it produces most spores on potassium nitrate, about 0.09×106cfu/ml; The pathogen optimal carbon sources were sucrose. Stopped to grow when 40℃,the mycelia growing optimum temperature was 30℃.6、Researchs on morphological feature of Fusarium. tricinctum:It growed fastest on potassium nitrate as the nitrogen source, the diameter of the colonies reaches3.99 cm after days,and it produces most spores was about 29.73×106cfu/ml after 7 days;The three species pathogen optimal carbon sources were sucrose and it was 0.97×106cfu/ml.Mycelial growth of PH range of 4~8, the optimal P H was 8.Stopped to grow when40℃, the mycelia growing optimum temperature was30℃.7、Researchs on morphological feature of Fusarium. tabacinum: It growed fastest on potassium nitrate as the nitrogen source, the diameter of the colonies reaches 1.77 cm after 7 days, and it produces most spores was about 5.13×106cfu/ml after7days; The pathogen optimal carbon sources were sucrose. Mycelial growth of PH range of 4~8, the optimal P H was 8. Stopped to grow when40℃,the mycelia growing optimum temperature was 30℃and spore production temperature was 25℃.