Development of Disease Predictive Model for the Management of Bacterial Blight of Eucalyptus Through Chemothrapy
摘要
Bacterial leaf blight of eucalyptus caused by Xanthomonas axonopodis pv. eucalyptorum is the most damaging disease in all major eucalyptus plantation areas of Pakistan. Survey was conducted to estimate the disease incidence in Irrigated Forest Plantations of Shorkot (Jhang), Chichawatni (Sahiwal) and Changa Manga (Kasur) of Punjab, Pakistan. Maximum disease incidence (>30%) was recorded in Shorkot plantation which was the largest eucalyptus growing area. For the management of bacterial leaf blight of eucalyptus, various chemicals (Copper Hydroxide, Copper oxychloride, Azoxystrobin, Forum Top, Cabrio Top, Copper Sulphate, Kasugamycin, Folio Gold and Nativo) were evaluated under lab, greenhouse and field conditions. In the lab conditions Copper Hydroxide and Copper oxychloride showed maximum inhibition zone. Then these two chemicals were tested in combination and alone in the greenhouse and field conditions. In greenhouse combination of both displayed minimum disease and similar findings were observed in field study. Climate plays a significant role in development of disease, thus correlation between environmental factors such as max. and min. temperature (oC), rainfall (mm), relative humidity (%), wind speed (Km/h), were studied and on the basis of two years data predictive model was developed which showed > 90% variability. The present study revealed that Copper based chemicals suppressed the bacterial blight disease of Eucalyptus.