The insecticidal effects on three pest insects and the influence of high-concentration CO_2 fumigation under high temperature conditions on the quality of apples and Japanese pears were investigated. 1. Larvae of the oriental fruit moth, Grapholita molesta, were completely killed by 60% CO_2 – 16 hours, and diapausing females of the two-spotted spider mite, Tetranychus urticae, were 100% eliminated by 40% CO_2 - 24 hours at 35 ℃. However, larvae of the peach fruit moth, Carposina sasakii, were not all killed by CO_2 fumigation. 2. Different apple varieties showed different degrees of carbon dioxide injury. None was seen in 'Tsugaru', 'Jonagold' or 'Orin', whereas 'Fuji' was clearly susceptible. In the Japanese pear varieties 'Kosui' and 'Hosui,' CO_2 fumigation worsened water soaking injury resulting from fruit senescence, and carbon dioxide injury also occurred with high frequency in both varieties. 3. In 'Hosui,' 1-methylcyclopropene treatment tended to reduce carbon dioxide injury, but aggravated it in 'Kosui' and 'Fuji'. These results indicate that it is not feasible to apply high concentrations of CO_2 fumigation as a quarantine measure for Japanese pears under high temperature conditions; however, it may be applicable to certain varieties of apple and for certain pest species.
雑誌名
果樹研究所研究報告
雑誌名(英)
Bulletin of the National Institute of Fruit Tree Science