Prevalence of microflora associated with different rice varieties and its impact on sowing seed quality

Abstract

A total of 28 rice varieties were procured from Plant Breeder (Rice), JNKVV, Jabalpur. The collected seeds were placed in a butter paper envelop and stored at low temperature (40C) to avoid any further deterioration. The rice seeds were tested for the association of mycoflora and its impact on sowing seed quality like seed germination, seed emergence and seedling vigour. The mycoflora that were associated with diseases, were identified based upon the symptoms and structure and fruiting bodies produced either under lab or field conditions. Effect of mycoflora was determined by standard ragdoll method, standard blotter method and seedling vigour index was calculated based on the seedling length by adopting the formula as recommended by Abdul- Baki and Anderson (1973). The association of Curvularia lunata ranged from 2.0-17.0%, Alternaria alternata 2.0-14.0%, Helminthosporium oryzae 2.0-11.0 % and Fusarium moniliforme 2.0-13.0%. Association of Pyricularia oryzae and Trichoconiella padwickii were not recorded. Significant reduction in seed germination and seedling vigour was observed in seed infected with Curvularia lunata (19%) and Altenaria alternata (24%) in mahamaya and varalu varieties respectively.