Study On The Chemotaxis Of Main Ginseng Disease To Saccharides And Amino Acids Of Ginseng Root Exudates

Chemicals released from the plant roots can be identified by microbe and open the rhizosphere dialogue between plants and soil microorganisms.Root exudates is a precursor of the rhizosphere effect.More studies have shown that chemotaxis response is an important way of many pathogens to recognize host plant signals and to successfully infect host.Therefore,the chemotaxis of main ginseng disease to exogenous saccharides and amino acids of ginseng root exudates was studied.They also have important theoretical and practical significance on solving reducing ginseng diseases and pests occurrence and ginseng soil sickness.The results were as follows:1)when pH was 8,concentration was 0.025 mg· L^-1,culture temperature was 25 ℃and the duration was 60 minutes,the optimal chemotaxis rates of lysine was 2.5097;when pH was 6,concentration was 0.25 mg· L^-1,culture temperature was 25 ℃and the duration was 60 minutes,the optimal chemotaxis rates of Arginine was 2.2188;when pH was 7,concentration was 0.25 mg· L^-1,culture temperature was 25 and the duration was 60 minutes,the optimal chemotaxis rates ℃ of Isoleucine was 2.164;when pH was 8,concentration was 0.025 mg· L^-1,culture temperature was 25 and the duration was ℃ 75 minutes,the optimal chemotaxis rates of Phenylalanine was 2.6699;when pH was 8,concentration was 0.25 mg· L^-1,culture temperature was 25 ℃and the duration was 75 minutes,the optimal chemotaxis rates of Glycine was 2.5829;when pH was 8,concentration was 0.25 mg· L^-1,culture temperature was 25 and the duration was ℃ 75 minutes,the optimal chemotaxis rates of Cysteine was 3.1403;when pH was 7,concentration was 0.25 mg· L^-1,culture temperature was 25 and the duration was 60 minutes,the optimal chemotaxis rates ℃ of Mannose was 2.7525;when pH was 6,concentration was 0.25 mg· L^-1,culture temperature was 25 and the duration was ℃ 75 minutes,the optimal chemotaxis rates of lysine was 2.4577;when pH was 7,concentration was 0.25 mg· L^-1,culture temperature was 30 ℃and the duration was 60 minutes,the optimal chemotaxis rates of L-Rhamnose was 3.0912;when pH was 6,concentration was 0.25 mg· L^-1,culture temperature was 30 ℃and the duration was 45 minutes,the optimal chemotaxis rates of D-Arabinose was 3.0263.Sugars and amino acids have obvious chemotaxis with Erwinia carotovora,the high concentration of carbohydrate and amino acid has inhibitory effect on chemotaxis response of Erwinia carotovora,and the chemotaxis response decreased with the increase of concentration of carbohydrates and amino acids.2)Phenylalanine,Alanine and L-rhamnose had obvious chemotaxis to Fusarium solani.Chemotaxis mobile index were 1.3234,1.2540,1.2712;Chemotaxis growth rate were 0.547,0.503,0.485;The spore germination rate were 58%,52% and 58% respectively;dry weight of Mycelial were 0.0359,0.0412,0.0285,respectively.The dry weight of mycelium,growth rate and spore germination rate of Fusarium solani were significantly increased.3)Aspartic acid,Cysteine and L-rhamnose had obvious chemotaxis to Cylindrocarpon destructans.Chemotaxis mobile index were 1.2687,1.2654,1.2230;Chemotaxis growth rate were 0.541,0.485,0.463,the spore germination rate were 55%,61%,50%;dry weight of Mycelial were 0.0419,0.0455,0.0302,respectively.The dry weight of mycelium,growth rate and spore germination rate of Cylindrocarpon destructans were significantly increased.4)Arginine,Glutamic and Galactose had obvious chemotaxis to Botrytis cinerea.Chemotaxis mobile index were 1.2801,1.2254,1.2325;Chemotaxis growth rate were 0.583,0.583,0.547;The spore germination rate were 67%,59% and 67% respectively;dry weight of Mycelial were 0.0514,0.0382,0.0428,respectively.The dry weight of mycelium,growth rate and spore germination rate of Botrytis cinerea were significantly increased.