Effect of biofertilizers, biological control agents and soil amendments on the control of saffron corm rot (Crocus sativus L.)

Abstract

Saffron corm rot caused by Fusarium monliforme var. intermedium, Fusarium oxysporum and F. gladioliis a serious threat to saffron cultivators of Jammu and Kashmir. About 46% of the soil in the saffron fields are infected with the said fungus and the infection is spreading steadily. Longer planting cycle (up to 15 years), primitive agronomic practices, monocropping of saffron, along with the use of non-graded corms and continual use of diseased material resulted in the frequent occurrence of corm rot diseases. Three biocontrol agents viz., Tricoderma viride, Tricodermaherzanium and Pseudomonas florescence having antagonistic activity against corm rot of saffron were used as seed treatment. Similarly three biofertilizers, viz., Azatobacter, Azospirillium and vermicompost were evaluated against corm rot of saffron. Mustard cake, Dal weed and Neem cake were used as soil amendments. Study carried over 39 on farm trials conducted over an area of about 1 ha. Confirmed efficacy of Tricoderma viride when used as a corm dresser in combination with vermicompost and Neem cake applied to the soil directly in control of saffron corm rot under two years planting cycle to the extent of 98%. The study has indicated that all the morphological, yield and yield attributing traits showed significant differences for all the treatments used in the experiment. Maximum corm yield (792.66 g m-2), number of daughter corms/mother corm (3.01), fresh flower weight (217.77 g plot-1) and saffron yield (7.96 kg ha-1) was obtained with the treatment combination of Tricoderma herzanium, Azospirillum spp. and Mustard cake.