Study On The Effect Of Trichokonins On The Growth Of Lilium Orientals And The Control Of Botrytis Cinerea

Trichokonins（TKs）is a kind of peptaibols antimicrobial peptide isolated and purified from the solid culture of Trichoderma longicornis SMF2.It has many biological activities,such as antimicrobial,antiviral,inducing plant resistance and promoting plant growth,and can effectively control plant diseases.Lily is a bulbous flower belonging to Liliaceae,which has ornamental,edible and medicinal value.Botrytis cinerea is one of the main diseases of lily,which seriously affects the yield and quality of lily and restricts the annual commercial production of lily.In this paper,the effects of a new biological pesticide TKs on the growth of Oriental Lily and the control of Botrytis cinerea were studied with Sorbonne as experimental material.The results are as follows:1.The effects of TKs on the growth of lilium oriental were studied.The results showed that the concentration of TKs in the range of 0.1 mg/L to 0.4 mg/L could significantly promote the plant height,fresh weight and dry weight of lilium oriental.At the optimum concentration,plant height,aboveground fresh weight,underground fresh weight,aboveground dry weight and underground dry weight increased by 30.18%,51.65%,62.59%,79.63%,42.43%respectively compared with the control.It also promoted root length,total surface area,total projection area,total volume,average diameter,total root tip number,total bifurcation number and total crossover number of Lily roots.At the optimum concentration,the root length,total surface area,total projection area,total volume,average diameter,total root tip number,total bifurcation number and total crossover number of lilium oriental increased by 102.65%,214.67%,263.47%,288.06%,119.64%,276.85%,329.00%,498.00%respectively compared with the control.Root length,total surface area,total projection area,total volume,average diameter,total root tip number,total bifurcation number and total crossover number increased by105.51%,107.26%,108.47%,137.04%,46.67%,327.93%,159.33%,174.04%,respectively.The promotion effect on stem rooting was more obvious than that on basal rooting.The stomatal conductance,net photosynthetic rate and intercellular CO₂ concentration of upper leaves increased by139.22%,485.88%and 23.23%respectively compared with the control at the optimum concentration of TKs.The stomatal conductance,net photosynthetic rate and intercellular CO₂ concentration of middle leaves increased by114.41%,272.36%and14.21%respectively,while stomatal conductance,net photosynthetic rate and intercellular CO₂ concentration of lower leaves increased by 44.92%,215.91%and14.89%respectively,which had little effect on fluorescence kinetics parameters of lilium orientalis.2.The pathogen of botrytis cinerea of lilium orientals’Sorbonne’was isolated and identified,and the biological characteristics of the pathogen were studied.The pathogen of Botrytis cinerea Pers.was isolated by tissue isolation method,purified by single cell isolation method,verified by Koch’s law,identified by morphological identification and molecular biological identification.The biological characteristics of pathogenic bacteria were studied from six aspects:culture medium,temperature,light,pH,carbon source and nitrogen source.The results showed that the optimum conditions for mycelial growth and sporulation of Botrytis cinerea were PSA medium,20℃,alternating light and dark（12h light/12h darkness）,pH 5-6,soluble starch and sucrose as carbon source,beef paste and ammonium sulfate as nitrogen source.3.The control effect of TKs on botrytis cinerea of lilium orientals was studied.（1）The indoor toxicity of six agents to botrytis cinerea was determined.The results showed that TKs had a certain inhibitory effect on the pathogenic fungi of botrytis cinerea.The EC₅₀ of TKs on the mycelial growth of botrytis cinerea was 7.00mg/L,which was the third of the six medicines.The EC₅₀ of spore germination of botrytis cinerea was 199.90 mg/L,which was the maximum.The inhibition effect of spore germination of botrytis cinerea was the worst among the six medicines.（2）The control effect of TKs on gray mould of potted oriental lily was studied.Two kinds of experiments were carried out,spraying leaves and irrigating roots with chemicals to control and induce disease resistance.The results showed that the relative control effect of leaf spraying treatment was higher in the range of 10mg/L⁴0 mg/L,while that of root irrigation treatment was higher in the range of 0.1mg/L⁰.4 mg/L.