Piriformospora indica promotes plant growth, reduces lodging and enhances seed yield, and quality in onion (Allium cepa)

The onion seed crop is affected by several bacterial and fungal rot, which causes lodging, yield, and seed quality losses. In the present study the performance of three biocontrol agents- Piriformospora indica, Vesicular arbuscular mycorrhiza (VAM) and Trichoderma viride with fungicide and bactericide as a standard control in reducing lodging and enhancing the seed yield and quality in onion was evaluated. The results showed that among the bioagents, indica recorded the highest bulb germination (98.39%), highest plant stand (87.10%), umbel diameter (5.01 cm), and lowest lodging (27.56%). Whereas VAM recorded the highest plant height (53.53 cm). The performance of P. indica was equivalent to standard chemical control carbendazim for several characteristics and even superior in characteristics like–seed yield (22.60 g/plant) and seed quality traits like–1000-seed weight (3.69 g), and seed vigour index-II (209.76). These results suggest that onion bulb treatment with P. indica is beneficial in reducing pesticide use and lodging, and increasing the productivity and seed quality. To the best of our knowledge, this is the first report on the use of P. indica in onion seed crop. Onion seed crop is pollinated by insects, primarily by honeybees, which are highly susceptible to pesticide applications. Therefore, onion seed bulb treatment with P. indica can be an essential component of integrated crop management in onion seed production for sustainable agriculture.