บทคัดย่องานวิจัย

หมวดหมู่ : ฐานข้อมูลงานวิจัย

Models to predict potato tuber infection by Pythium ultimum from duration of wetness and temperature, and leak-lesion expansion from storage duration and temperature

L.H. Lui and A.C. Kushalappa

Postharvest Biology and Technology, Volume 27, Number 3, March 2003 , pp. 313-322.

2003

บทคัดย่อ

Models to Predict Potato Tuber Infection and Lesion Expansion in Storage by Pythium Ultimum

Leak, caused by Pythium ultimum, is one of the important postharvest diseases of potatoes. Models were developed to predict the potential of leak development from important factors influencing infectiion and lesion expansion, so that they could be used as a tool to manage leak in potato after harvest. ‘Russet Burbank’ potato tubers were surface sterilized, wounded and inoculated with 20 mL of 104 sporangia/mL suspension of P. ultimum and incubated in mist chambers placed in growth chambers. For the infection study, inoculate tubers were kept at 4, 8, 12, 16 and 20 oC. After 3, 6, 12, 24 and 48 h of incubation time samples of 5 tubers were removed, dried and stored at 12 oC and 95% RH. After 30 d of storage tubers were removed and the disease severity was assessed. For lesion expansiion study, inoculated tubers were maintained in mist chambers for 24h, at 16 C, for the establishment of initial infections, and then, the tubers were dried in laminar flow, and stored at 4, 8, 12, and 16 oC , for 15, 30, 45, 60, 75 and 90 d , at 95% RH. At the end of the storage time, 6 tuber were removed and the disease severity was assessed and transformed to proportion of volume diseased (PVD). A cubic model to predict infection potential from incubation temperature and duration of wetness explained 96.75% of the variation in PVD. A cubic model to predict lesion expansion potential as a function of storage temperature and duration explained of 99.5% of the rariation in PVD.