ประสิทธิภาพของน้ำส้มควันไม้ยูคาลิปตัสร่วมกับเชื้อ แอกติโนไมซีสต์ในการควบคุมเชื้อรา Colletotrichum gloeosporioides สาเหตุโรคแอนแทรคโนสของมะม่วง พันธุ์น้ำดอกไม้

Abstract

Mango fruits cv. Nam Dok Mai showing typical anthracnose symptoms were collected from markets in Amphoe Mueang, San Pa Tong and Phrao, Chiang Mai. The symptoms from each sample were same. Thirty-five isolates of Colletotrichum gloeosporioides were suscessfully isolated and divided into 5 groups according to color of colony; white, greyish-white, dark grey, light grey and grey. Morphological characteristics according to Sutton (1992) and effects on pathogenicity of all isolates were the same. Eucalyptus wood vinegar at 0.5 and 1.0% concentration inhibited colony growth of C. gloeosporioides; NDM_MuF3, NDM_MuF10, NDM_SptF5, NDM_PhF12 and NDM_PhF17, ranging from 37.14 – 61.48 and 18.90 – 26.67%, respectively. However, wood vinegar was not affected to hyphal tip of fungal pathogens, but could inhibit colony growth with time in term of delay germination. Moreover, wood vinegar was also inhibiting conidial germination of pathogen until 18 h after treatment. Although germ tube of treated conidia was shorter than control, wood vinegar had no effect on morphological characteristics of conidia. In addition, wood vinegar at 1.0% concentration had more efficiency than 0.5% concentration both inhibition of colony growth and conidial germination. When mixed the suspensions of six actinomycetes; NSP1, NSP2, NSP3, NSP4, NSP5 and NSP6, with eucalyptus wood vinegar to final concentration at 0, 0.5 and 1.0%, amount of actinomycetes in control (0%) was had 4.4 × 105, 1.6 × 105, 1.4 × 106, 1.5 × 106, 4.8 × 104 and 1.4 × 106 CFU/ml, respectively. While actinomycetes in mixed suspensions with wood vinegar at 0.5% was increased to 3.3 × 106, 2.5 × 106, 1.4 × 106, 2.3 × 107, 2.6 × 107 and 2.8 × 107 CFU/ml, respectively. But in actinomycetes in mixed suspensions with wood vinegar at 1.0% become to actinomycetes was decreased to 3.6 × 105, 5.2 × 105, 4.3 × 105, 2.5 × 105, 7.0 × 103 and 8.3 × 104 CFU/ml, respectively. Furthermore, efficiency of actinomycetes mixed with wood vinegar (both 0.5 and 1.0%) on inhibiting colony growth of pathogens was increased to 72.82 – 82.05 and 78.97 – 83.59%, respectively. While actinomycetes alone inhibited ranging from 76.92 – 80.51%, respectively. When tested using dual culture technique. However, using agar well diffusion method on testing efficiency of actinomycetes mixed with wood vinegar was not suitable method; percent inhibition was decreased. Furthermore, the NSP5 mixed with wood vinegar (both 0.5 and 1.0%) could completely inhibit (100%) conidial germination of pathogens until 24 h after treatment. However, actinomecetes mixed with wood vinegar could only inhibit colony growth and conidial germination with time in term of delay germination, but not affected to abnormalities of pathogens. In addition, anthracnose disease on mango fruits cv. Nam Dok Mai was decreased when immersed fruits in the NSP1 mixed with wood vinegar at concentration 1.0% for 1 min in term of eradication; gave 58.33% of biocontrol efficiency. Furthermore, quality of mango after test comparing with normal mango was scored by five examiners which in rate of acceptable and favorable level (score 4 from 5).