P.K. Rai

Recent Perspective of Next Generation Sequencing: Applications in Molecular Plant Biology and Crop Improvement

Nearly after three decades of Sanger sequencing method dominating the field of nucleotide sequencing, the new age of novel sequencing techniques commenced with 454-pyrosequencing in the year 2005 and thus started the era of next generation sequencing techniques. Since then many other novel sequencing techniques with increased accuracy, simplicity and cost-effectiveness have come up and called next to next generation sequencing techniques or third generation sequencing techniques. The scientific knowledge generated from next generation sequencing techniques has transformed the field of structural and functional genomic studies in different crop plants. In this review, various next generation sequencing techniques are described, with their applications and future prospective.

Efficacy of Micro-Nutrients, Fungicides and Bio-Agents against Sclerotinia Stem Rot (Sclerotinia sclerotiorum) of Indian Mustard

Sclerotinia sclerotiorum (Lib.) de Bary is a broad range fungal pathogen which attacks more than 500 species of higher plants (Boland and Hall, 1994; Saharan and Mehta, 2008; Sharma et al.,, 2015a). The pathogen can cause serious losses in yield and quality on numerous important field and vegetable crops (Purdy, 1979). Stem rot of Indian mustard caused by S. sclerotiorum (Lib.) de Bary has become important in recent years in India and elsewhere with high disease and severe yield losses (Ghasolia et al., 2004; Sharma et al., 2017). Management of S. sclerotiorum is a major challenge faced by plant pathologists. Management is difficult, uneconomical and inconsistent due to the presence of wide host range and long-term survival of the resting sclerotia. Numerous reports indicate that amendment of soil with certain organic or inorganic matters is effective in controlling soil borne pathogens. Soil amendment with mustard cake, sesame International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 6 Number 10 (2017) pp. 620-626 Journal homepage: http://www.ijcmas.com

Seed-borne Mycoflora associated with Stored Mustard (Brassica juncea L.) Seeds and their Pathogenic Potential

Six fungal genera viz., Alternaria, Rhi-zoctonia, Penicillium, Aspergillus, Curvularia and Rhizopus were found associated with seeds of two popular Indian mustard (Brassica juncea L.) varieties stored for different priods. Per cent inci-dence of different fungi varied with duration of storage period and detection methods used. The incidence of A. brassicae was highest (48%) fol-lowed by A. brassicicola (20.3%) and Rhizoctonia bataticola (18.3). The seed germination percent-age and vigor index decreased with increasing the storage period. Germination of seeds ranged from 55 to 95% in respect of variety and storage period. The highest vigor index in both the varie-ties was recorded in seeds stored for 6 months. Modified PDA method was found efficient in de-tecting the seed-borne incidence (13.2%) fol-lowed by standard blotter (11.1%) and deep-freezing blotter method (6.9%).

Ovule Fertility and Seed Set in Oilseed Brassicas

Present study illustrates the effect of number of ovules/gynoecium and their fertility on seed yield in oilseed Brassicas. Amongst the nine different species of the family Brassicaceae analyzed, the maximum number of ovules/gynoecium was recorded in Brassica napus (2830) followed by Eruca sativa (22–24), B. carinata (20–22) and B. juncea cv. Geeta (18–20), while the minimum was observed in Crambe abyssinica (01). The number of seeds developed in each siliqua was in accordance with the number of fertilized embryo sacs, indicating little or no embryo abortion during seed development. Moreover, it was also revealed that the number of ovules with embryo sac is more closely correlated to ovule fertility than to the number of ovules/gynoecium. The observation indicates that ovule fertility, rather than the number of ovules/gynoecium, determines seed yield in oilseed Brassicas.