Evaluation of Phytophthora infestans control determined by decision support systems: Simphyt and NegFry.

摘要

An experiment was carried out aimed at validation of late blight control conducted according to 2 decision support systems (DSS) at Winna Gora near Sroda WLKP in Poland. Two cultivars of potatoes were used: Salto (susceptible to late blight) and Satina (moderately resistant). Fungicide applications determined by NegFry and Simphyt systems were compared to a routine fungicide programme. At Winna Gora in 2004, the deficiency of rain and cool nights in spring did not support an early appearance of late blight. The weather conditions favoured the late blight development in August when 68 mm of precipitation and warmer nights were registered. It resulted in a much faster development of symptoms of late blight. The analysis of variance of area under the disease progress curve (AUDPC) proved the significant influence of cultivar resistance on the development of symptoms caused by late blight. Significant differences of that feature appeared between treated and untreated plots. However, differences in AUPDC between plots treated routinely and according to DSS were not significant. Chemical control caused significant increase of yield in comparison to the untreated plots, but the increase of applications over the optimum number did not resulted in higher yields. Both Simphyt and NegFry enabled to decrease the costs of late blight chemical control..