The effect of attractants acted by microorganisms to Dacus dorsalis Hendel

• Main Authors: Jui-Chun Chang, 章瑞駿
• Other Authors: Yu-Chang Liu
• Format: Others
• Language: zh-TW
• Published: 1994
• Online Access: http://ndltd.ncl.edu.tw/handle/13892065824534866340

碩士 === 國立中興大學 === 昆蟲學系 === 82 === Four available substances including molasses, protein hydrolysate, yeast powder and Shao-Shing wine-dreg were selected and tested for attracting the oriental fruit fly, Dacus dorsalis Hendel, by screening their concentrations, mixed each other with various ratios and acting with microorganisms. It showed that the most effevtive concentration was 30% for yeast powder with which the high attractiveness of 39.7% was obtained in luring this fly, and for molasses it was 50%, at which it was the only one that attracted to females more than to males among all the tested substances. The best concentration for protein hydrolysate was 70% while 50% for Shao-Shing wine-dreg. When substances mixed with each other by various mix ratios, it is found that the most effective mix ratio for each substance in attracting flies was 7:3 for yeast powder mixed with protein hydrolysate, 7:3 for yeast powder mixed with molasses, 5:5 for protein hydrolysate mixed with molasse. Except Shao-Shing wine-dreg, the attractiveness of mixtures of the other three substances were all higher more than 1.3 times than each substance used alone. In testing of attractants acted by "ftuit fly type"bacteria, it showed that protein hydrolysate metabolized by Enterobacter cloacae had a high percentage of attraction(60.3%)to the laboratory-reared fly individuals, which was 2 times higher than the uninoculated attractant, however, when tested in guava orchard, it is found that the protein hydrolysate inoculated by Citrobacter freundii was the most effective one to the wild flies, 49.7 flies attracted per day, showed the most effective attraction among all the attractants acted by microorganisms in this test. Molasses with 50% concentration decomposed by Aspergillus oryzae var. effusus (3.68x106) for one day had 61.3% of attractiveness, while the same material inoculated by A. oryzae var. effusus and Saccharomyces cerevisiae and fermented for 4 days, had increased the attractiveness to 64.7%, 1.7 times better.