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Drought is key abiotic stress that reduced crop growth, development and yield. While several physiological processes are played role in plant adaptations to drought stress. However, antioxidant defense system and lipid peroxidation play a key role in drought tolerance. The current study was intended to investigate physiological adaptations for drought tolerance in different wheat varieties. Three weeks old seedlings of each wheat cultivar were challenged with drought stress by skipping irrigation. After the drought stress of two weeks, plants were subjected to morphological, biochemical and physiological investigations. Drought stress reduced the biomass and enhanced the root length in all three wheat varieties. However, growth reduction due to drought stress was relatively lower in variety F23. While the shoot length of all three wheat varieties was decreased because of drought stress, whereas the root/shoot ratio was increased. The root length was higher in variety F23. The chlorophyll a and b were decreased due to water shortage. Variety Pu19 had greater chlorophyll contents in comparison to other wheat varieties in drought conditions. The total soluble proteins, proline, glycinebetaine and phenolic contents were improved in all three wheat varieties under drought stress. The variety Pu19 was exhibited a higher level of proline, glycine betaine and phenolic contents were. Similarly, hydrogen peroxide (H2O2) and malondialdehyde (MDA) were improved in all three wheat varieties but this increase was relatively lower in variety F23. The superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities were improved in all wheat varieties in a water shortage. The variety F23 exhibited higher antioxidants levels which are positively associated with its potential of drought stress tolerance. This study provided a helpful understanding of the significant role of the antioxidant defense system of wheat crop especially the variety F23 in drought stress tolerance. [ABSTRACT FROM AUTHOR]

Salinity is a major abiotic stress that reduces the plant productivity. The plant growth promoting rhizobacteria (PGPRs) play important role in eliminating the effect of salinity. Cicer arietinum L. is an important legume crop having high quantity of proteins. In the present study, four varieties (CM44, CM91, CM98 and CM2000) were grown in the presence and absence of PGPR inoculated media and nitrogen in different salinity levels (20, 50, 100, 200 and 300mM NaCl). The biomass production of the varieties CM91 and CM98 increased at 20-100mM NaCl concentrations but drastically decreased at higher levels. While in varieties CM44 and CM2000 a gradual decrease of biomass with increasing salinity levels were observed. Number of pods, flowers and fresh weight of pods were not affected at salinity levels of 0-50mM and decreased at 100 mM NaCI in all the four varieties. In varieties CM91 and CM2000 nodules were formed at all levels of salinity treatments, while in varieties CM44 and CM98 nodules were formed at salinity levels of 0-50 mM NaCl and completely inhibited at 100mM NaCl. The total protein and nitrogen contents increased with concurrent increasing levels of NaCI. The plants treated with 50 mM NaCI had maximum amount of protein contents as compared to those at 0mM NaCI level. Varieties CM91 and CM2000 had higher protein contents than CM44 and CM98. At I/50 level of salinity the total protein contents were found more than inoculated control at 0mM NaCI. From this study, it is concluded that PGPRs can play an important role to mitigate the salt stress at different concentrations for better crop yield. [ABSTRACT FROM AUTHOR]

Salinity is a major soil problem limiting plant growth and development. Application of plant growth promoting rhizobacteria (PGPR) is effective against this stress. Mung bean is an important crop that is used as food. Present experiment was conducted under natural environment to evaluate the effect of PGPR on biomass production, nitrogen and proteins percentage of four mung bean varieties under different NaCI levels in sand culture after 5,7 and 9 weeks of sowing. Both inoculated and uninoculated plants were grown on mineral medium that were N-free either without NaCI or with a range of NaCI (20, 50,100, 200 and 300mM). Dry weight of plants was increased at 0-50mM NaCl and decreased at 100-300mM NaCI concentration. Inoculation effectively increased the dry weights of plants at salinity levels of 0-50 mM NaCI as compared to uninoculated plants but was not effective at 200-300mM NaCI. Number and fresh weight of pods were not affected at 0-100 mM NaCI levels of salinity but strongly decreased at 200-300 mM NaCl. Number and fresh weights of nodules increased slightly at lower levels (20-I00 mM) of salinity but strongly decreased at 200 mM NaCI. Nodulation and pods were completely inhibited at 300mM NaCl. The nitrogen percentage was decreased in salinity stress. The total protein contents increased with increasing levels of NaCI concentration. The plants in 50 mM NaCI maintained maximum amount of protein contents as compared to those at 0mM NaCI level. Varieties MI and NM92 had higher protein contents than M6 and NM98. From these findings it is concluded that PGPR can play an effective role in increasing crop production in saline soil. [ABSTRACT FROM AUTHOR]

A comparative study of stem epidermis of fourteen sugarcane varieties (i.e., L-l18, CP72-2086, CP43-33, HSF-240, CPF-237, SPF-213, COjv-84, CO-1148, COL-54, COL-29, CO-975, BL-4, Triton and BF-162) was carried out using Schultz's maceration method followed by staining with chloloiodide of Zinc. The results indicated substantial differences among the sugarcane varieties for various stem epidermal cell combinations and structures like number of stomata, number and shape of cork, silica, long, and pointed elongated cork cells. It is therefore contended that the structure of the epidermis in sugar cane can be used as a characteristic of variety differentiation. [ABSTRACT FROM AUTHOR]