Powdery mildew incidence and conidial variability of E. polygoni in the samples collected from major fenugreek growing areas of North Gujarat

Abstract

A survey was conducted during 2011–12 to assess the incidence and intensity of powdery mildew caused by Erysiphe polygoni DC. on fenugreek in major growing areas of North Gujarat. The disease was prevalent in both Banaskantha and Patan districts, with higher incidence in Banaskantha (75.55%) than Patan (66.66%). Among talukas, the highest disease incidence was recorded in Vav (86.66%). Powdery mildew was not observed at the vegetative stage, while disease intensity increased from pod formation to maturity, reaching a maximum of 68.48% in Vav. Morphological studies of conidia revealed variability among samples collected from different talukas. The maximum average conidial length (35.44 ± 2.51 µm) was recorded in Vav, whereas the maximum average breadth (19.13 ± 2.27 µm) was observed in Siddhpur. The highest average length/breadth ratio (1.87) was recorded in Vav. The study revealed considerable variation in powdery mildew incidence, intensity and conidial characteristics of E. polygoni in fenugreek-growing areas of North Gujarat.