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The present piece of work was conducted in the Seed Physiology Laboratory of Institute of Agricultural Sciences, Banaras Hindu University in the year 2011-12, where the rice seeds variety MTU 7029 were primed with different combinations of kinetin (in ppm) and magnesium nitrate (in mM) (2.5 ppm+2 mM, 2.5 ppm+4 mM, 2.5 ppm+6 mM, 2.5 ppm+8 mM, 5 ppm+2 mM, 5 ppm+4 mM, 5 ppm+6 mM, 5 ppm+8 mM kinetin and magnesium nitrate respectively) whereas; seeds without any treatment referred as control (non-primed). Various physiomorphological (shoot and root lengths (in cm), root number, fresh and dry weights (in g)) and biochemical (proline content (mg g-1 dry weight of seedlings), total chlorophyll content (mg g-1) and superoxide dismutase activity (unit×102 g-1 min-1 fresh weight of leaf; at 20 days after sowing)) parameters were studied in the seedlings, obtained from 10, 15 and 20 DAS old primed and non-primed plants. All the primed seeds were found to perform better as compared to non primed control one. However, treatment 2.5 ppm kinetin+4 mM magnesium nitrate performed best among all the treatments and all the studied parameters such as shoot and root lengths, root number, fresh and dry weights, proline content, total chlorophyll content and superoxide dismutase activity in 10, 15 and 20 days after sowing. [ABSTRACT FROM AUTHOR]

The aim of the study is to establish a routine procedure for high frequency plant regeneration from in vitro raised embryogenic callus of indica rice var. MTU 7029. In the present piece of work, various concentrations of surfactants [sodium hypochlorite (10 to 30%) and mercuric chloride (0.01 to 1%)] were tested and best concentration of surfactants was chosen according to the parameters like callus induction percentage and its growth as well as status of contamination. On the basis of available data of the said parameters, 0.1% mercuric chloride has shown best performance in all the aspect for surface sterilization of mature rice seeds for 5 minutes and the percentage of the contamination was also very less. The effect of synthetic auxin [2,4-D (0 to 4 mg L-1)], cytokinin [kinetin (0 to 1 mg L-1)], sucrose (0 to 50 g L-1), agar (6-16 g L-1) and growth medium (MS, N6 and LS) on callus induction were optimized to achieve high frequency plant regeneration from fresh embryogenic callus without further subculture. Results suggests that 2 mg L-1 2, 4-D, 30 g L-1 sucrose, 8 g L-1 agar and MS basal medium were best for embryogenic callus induction. From the present piece of work an efficient protocol was developed for in vitro embryogenic callus formation. [ABSTRACT FROM AUTHOR]

In the present piece of work the effects of seed priming with KNO3 on late sown sesame crop (Sesamum indicum) var. T-4 (V1), T-12 (V2) and Shekhar (V3) in respect of germination, physiomorphological, biochemical and yield parameters were observed. The treatments comprised of KNO3 [10 mM (T1), 15 mM (T2)] and distilled water (DW) primed sets (T0). The results showed that the KNO3 treatment promoted germination percentage, root and shoot length, fresh and dry weights of seedling, catalase, peroxidase and proline content as well as yield attributes like number of capsules plant-1, number of seeds capsule-1, test weight (1000 seed weight in g) and yield plant-1 (g). After 80 h, the highest germination percentage was recorded in 15 mM KNO3 (T2) primed seeds of Sesamum indicum var. T-4, T-12 and Shekhar. The average of root length, shoot length, fresh weight, and dry weight was recorded highest in treatment T2 in comparison to distilled water primed seeds (control) at 25 DAS in all varieties i.e., T-4, T-12 and Shekhar respectively. Yield attributes like number of capsules plant-1, number of seeds capsule-1, test weight and yield plant-1 were also highest in treatment T2 in all varieties V1, V2 and V3 respectively. Variety V1 and treatment T2 recorded the highest values of catalase, peroxidase and proline content followed by variety V3 and V2and treatment T1 and T0 at 45 DAS respectively. It had been found that seed priming with KNO3 ameliorate the effect of late sowing. [ABSTRACT FROM AUTHOR]

Due to anthropogenic as well as by natural factors the climate of earth is predicted to be warm by an average of 2-4 °C, at the end of the 21st Century. Emission of green house gases (GHG) from agricultural system is one of the major contributing factor in global warming. Heat stress is one of the major abiotic stresses threatening plant growth worldwide. Agricultural crops suffer in presenting their optimum yield potential due to heat stress. Heat stress causes enormous alterations in various processes within the plant system; most of them are well understood from various physiological, biochemical and molecular studies. Heat stress not only affects the morphological and phenological parameters but also the physiological and biochemical parameters like plant water relationship, photosynthesis, assimilate partitioning, hormonal changes, cell membrane stability, production of secondary plant metabolites, antioxidative metabolism, synthesis of heat shock proteins, cell signalling etc. In the advent of climate change and subsequent global warming there is an urgent need for understanding the physiological and biochemical basis of heat stress tolerance in crop plants. There has been a lot of effort worldwide in this regard to develop high temperature tolerant genotypes through transgenic intervention and genetic engineering. This paper reviews the literature supporting evidence for the morphological, phenological, physiological and biochemical effects of heat stress on several plants and different molecular approaches to develop transgenics tolerant to high temperature stress. A plethora of these kinds of plant responses are finally regulated by the genes. Hence, more biotechnological and molecular studies including genomics, proteomics, metaboliomics and the cryptomics are necessary to elucidate the processes further. [ABSTRACT FROM AUTHOR]