Prediction of Potato Late Blight Disease Based upon Environmental Factors in Faisalabad, Pakistan

Nadeem Ahmed

doi:10.4172/2157-7471.1000s3-008

Abstract

Potato late blight (PLB) caused by Phytophthora infestans (Mont.) de Bary, is an important and serious threat to successful potato production in the world. It spreads through seed and soil residual material. In Pakistan, PLB disease can induce 100% yield losses under epidemic condition. Due to lack of resistance in indigenous potato germplasm, disease is managed through fungicides by the growers of Pakistan. Excessive use of fungicides causes resistance in the pathogen and creates fatalistic effect on the environment. Disease predictive model under such situation may be effective tool to predict early onset of disease. A disease predictive model was developed on two years data of PLB disease severity and epidemiological factors using stepwise regression analysis. Model explained upto 80% disease variability. Maximum and Minimum temperature, relative humidity, rainfall and wind speed appeared to be most significant factors in the PLB disease development. The environmental conditions conducive for the development of PLB disease were characterized. Maximum and minimum temperatures in the range of 16-20°C and 1-6°C were found favourable for potato blight disease. Similarly, relative humidity, rainfall and wind speed in the range of 63-71%, 1.5-3.75 mm and 1-5.5 Km/h, respectively, were conducive for PLB disease which are helpful in disease development.

Highlights

P. infestans is a water mold lower fungus that infects potato crops during cool and wet weather, causing potato late blight
Relative humidity and wind speed were significant among environmental conditions with all five varieties i.e., Desiree, Diamont, SH-5, SH-339 and FD35-36 during two years
A significant correlation of Potato late blight (PLB) disease severity with minimum temperature was found except Desiree (r=0.81) during the two years

Summary

Introduction

P. infestans is a water mold lower fungus that infects potato crops during cool and wet weather, causing potato late blight. Potato late blight disease is seed and soil borne. U.S growers can experience annual losses of revenue of $210.7 million, $77.1 million being the cost of late blight fungicides alone [4]. In Pakistan, late blight of potato causing 50-70% potato yield loss under favourable environmental conditions [5,6] which can reach upto 100% [7]. Forecasting models that predict the likelihood of late blight outbreaks may provide important information for potato producers in Pakistan, enabling farmers to implement a timely disease management plan. For the most efficient and sustainable disease management strategies, epidemiological and biological data were used to develop a model for the management of late blight dynamics [9]

Methods

Results

Conclusion