Effect of Amendment of Soil with Shrimp and Crab Shell Powder on Control of Tomato Fusarium Wilt

• Main Authors: Chun-Wei Chen, 陳純葳
• Other Authors: 黃振文
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/76798645126359008149

碩士 === 國立中興大學 === 植物病理學系所 === 94 === Tomato Fusarium wilt is an important disease during summer season in Taiwan. Tomato seedlings were planted in nature soil and infested soil respectively treated with ten different organic amendments for seven days. Amendments of soil with rice husk, shrimp and crab shell powder, and oyster shell powder were able to enhance tomato growth and reduced disease severity of tomato Fusarium wilt. Application of shrimp and crab shell powder was significantly effective in reducing disease severity of tomato Fusarium wilt in greenhouse tests. The disease severity of tomato Fusarium wilt was significantly reduced 38.9％. In addition, the disease severity was reduced with increasing the concentration of shrimp and crab shell powder. The high pH values were observed in soil amended with 0.5、1.0％(w/w) shrimp and crab shell powder and chitin at day 0. However, the pH value of soil amended with chitin 14 days after treatment was lower than control, and the pH value of soil amended with shrimp and crab shell powder was still maintained higher 35 days after treatment. Concentration of ammonium increased rapidly, reached a peak in soil amended with shrimp and crab shell powder at 4th day or in soil amended with chitin at 7th day, and then decreased. Concentration of nitrite only increased in soil amended with shrimp and crab shell powder. After 4th day, concentration of nitrate in both treatments increased rapidly. Shrimp and crab shell powder and chitin stimulated proliferation of beneficial microorganisms including fungi, bacteria, and actinomycetes, and reduced population density of the pathogen. Fungal populations were significantly higher in soil amended with chitin than one with shrimp and crab shell powder. Soil amended with shrimp and crab shell powder and chitin also showed a high microbial activity detected by hydrolysis of fluorecein diacetate (FDA). The inhibitory effect of soil amended with shrimp and crab shell powder and chitin on conidial germination was nullified when soil was pre-treated by heat for 20 min at 100℃. The results suggest that the presence of microorganisms in soil may play an important role in suppression of tomato Fusarium wilt with shrimp and shell powder or chitin. It was concluded that soil amended with shrimp and crab shell powder could increase soil pH, microbial ability, also enhanced tomato seedling growth and reduced disease severity of tomato Fusarium wilt.