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Soil salinity is the serious problem of the arid and semi-arid tracts of the world. It causes great losses to agriculture by lowering the yields of various crops. However, such soil may be utilized either after reclaimation or by growing tolerant plant species. The degree of salt tolerance varies not only with plant species but the different varieties of the same species show variation in salt tolerance. Germination and seedling stages have a bearing on plant development at later stages of growth and ultimately crop yield. Therefore, in the present investigation, twelve varieties of oats viz., Colabagh, Kent,JHO-801, JHO-802,JHO-810,JHO-815,JHO-816, S-3021, S-2688, Chauripatti, UPO-201 and Sierra were tested for their relative salt tolerance to increasing levels of salinity in those combination of salts which nearly exist in the natural salt affected soils. Seeds were sown in petri dishes and were exposed to five salinity (40, 80, 120, 160 and 200 me/L. of salts) levels. The germination percentage, root and shoot length and dry weight of the seedlings decreased with increase in salinity. In general, varieties JHO-815, were found to be more tolerant at germination and seedling stages.

The aim of the present study was to assess the effects of different organic and inorganic fertilizers on the functional diversity of soil microbial community under a vegetable production system. The Biolog Eco-plate technique and indices, such as average well-colour development (AWCD), McIntosh and Shannon diversity were employed to study the diversity of soil microorganisms. The AWCD, i.e. overall utilization of carbon sources, suggested that different organic treatments had a significant impact on the metabolic activity of soil microorganisms. After 120h, the highest AWCD values were observed in poultry manure (2.5 t·ha)+vermicompost (3.5 t·ha) (0.63) and farm yard manure (FYM) (10 t·ha)+vermicompost (3.5 t·ha) (0.61). After 72h, the highest value of the McIntosh diversity index was recorded in poultry manure (2.5 t·ha)+vermicompost (3.5 t·ha) (3.87), followed by poultry manure (2.5 t·ha)+vermicompost (3.5 t·ha)+biofertilizers (Azotobacter 500 g·ha applied as seed treatment) (3.12). In the case of the Shannon diversity index, the highest values were noticed in organic treatments; however, there was no significant differences between organic and inorganic treatments. Biplot analysis showed a clear differentiation of organic treatments from the inorganic control. The amino acids, phenolics and polymer utilizing microorganisms were dominant in organic treatments. Inorganic control recorded the lowest values of the microbial diversity indices. Through this study, we have identified the best combination of organic nutrients, i.e. poultry manure (2.5 t·ha)+vermicompost (3.5 t·ha) for the stimulation of metabolically active soil microbial communities.

Twelve varieties of Oat (Avena sativa L.) were screened for relative drought tolerance based on the magnitude of chlorophyll stability index (CSI), relative water content (RWC) and free proline accumulation. IGFR1‐2670, IGFRI‐3021, IGFRI‐2688 and IGO‐8 showed a lower magnitude of CSI under stress condition in comparison to other tested varieties whereas the values of RWC and tree proline accumulation were higher. Based on the observations of this study it is concluded that, of the varieties tested, IGFRI‐2670, 3021 2688 and IGO‐8 are relatively more drought tolerant than the other genotypes tested. A close agreement was also noticed amongst the trends of CSI and proline accumulation, and per cent reduction in yield in rainfed over irrigated conditions.