Heat and drought are among the major obstacles confronting crop production under climate change. The present study was conducted to evaluate 50 diverse wheat genotypes for cell membrane stability (CMS) and chlorophyll content at seedling and anthesis stages under heat and drought stress conditions, to understand the effect of the two abiotic factors and to find promising genotypes for future breeding. Experiments were conducted in the glasshouse (seedling stage) and the field (anthesis stage). Analysis of variance showed significant variation (P ≤ 0.05) for all of the traits at seedling and anthesis stages. High levels of broad-sense heritability and genetic advance at 5% selection intensity indicated the presence of a high genetic component of variation and potential for genetic improvement through selection among the existing genetic variation. CMS showed a significant positive correlation with 1000-grain weight (TGW) under heat and drought conditions at both seedling and anthesis stages. Chlorophyll a/b ratio at seedling stage exhibited a significant negative correlation (r = –0.39, P < 0.05) with TGW under heat stress. Total chlorophyll content was significantly (r = 0.42, P < 0.05) correlated with TGW under heat stress at anthesis. Genotypes ETAD248 and ETAD7 showed the highest CMS and TGW values, whereas their chlorophyll a/b values were lowest, at both seedling and anthesis stages under heat and drought stress conditions. Higher CMS and total chlorophyll content, and lower chlorophyll a/b, were found to be useful indicators to identify genotypes with high TGW under heat and drought stress conditions. This study indicated the possibility of using seedling resistance as an indicator for later stage response in breeding for heat and drought resistance. The resistant genotypes identified can be used as potential germplasm in breeding programs.

Wheat is an important crop, used as staple food in numerous countries around the world. However, wheat productivity is low in the developing world due to several biotic and abiotic stresses, particularly drought stress. Non-availability of drought-tolerant wheat genotypes at different growth stages is the major constraint in improving wheat productivity in the developing world. Therefore, screening/developing drought-tolerant genotypes at different growth stages could improve the productivity of wheat. This study assessed seed germination and seedling growth of eight wheat genotypes under polyethylene glycol (PEG)-induced stress. Two PEG-induced osmotic potentials (i.e., -0.6 and -1.2 MPa) were included in the study along with control (0 MPa). Wheat genotypes included in the study were ‘KLR-16’, ‘B6’, ‘J10’, ‘716’, ‘A12’, ‘Seher’, ‘KTDH-16’, and ‘J4’. Data relating to seed germination percentage, root and shoot length, fresh and dry weight of roots and shoot, root/shoot length ratio and chlorophyll content were recorded. The studied parameters were significantly altered by individual and interactive effects of genotypes and PEG-induced osmotic potentials. Seed germination and growth parameters were reduced by osmotic potentials; however, huge differences were noted among genotypes. A reduction of 32.83 to 53.50% was recorded in seed germination, 24.611 to 47.75% in root length, 37.83 to 53.72% in shoot length, and 53.35 to 65.16% in root fresh weight. The genotypes, ‘J4’, ‘KLR-16’ and ‘KTDH-16’, particularly ‘J4’ better tolerated increasing osmotic potentials compared to the rest of the genotypes included in the study. Principal component analysis segregated these genotypes from the rest of the genotypes included in the study indicated that these can be used in the future studies to improve the drought tolerance of wheat crop. The genotype ‘J4’ can be used as a breeding material to develop drought resistant wheat genotypes.

To study "the effect of drought stress on Tomato (Lycopersicon esculentum) Cv. Bombino" an experiment was conducted at Institute of Biotechnology and Genetic Engineering, Agricultural University Peshawar. Tomato plants were grown in green house under two different conditions of water availability i.e.-controlled and drought. The parameters studied were relative water content (%), proline content (µmoles) and relative growth rate (weekˉ1). Drought stress has significant effect on all parameters studied. The relative water content of plant body decline during drought due to less water availability. In controlled environment, the mean value of relative water content was 89.28 while that observed in drought condition was 87.73. Proline was observed on rise due to continuous decrease in water quantity in cell sap. The value of proline content is 4.4 µmoles gˉ1 fresh weight in controlled condition whereas that the plants in drought condition had 5.8 µmoles gˉ1 fresh weight. Due to less water, photosynthesis was negatively affected which resulted in less energy production and finally low growth. In controlled condition the relative growth rate weekˉ1 on fresh weight was 1.37 gm whereas that of plant in drought condition was 0.57 gm.

The aim of this study was to develop statistical models for predicting the air permeability and light transmission properties of woven cotton fabrics and determine the level of correlation between the two parameters. Plain woven fabrics were developed with different warp and weft linear densities, ends per inch and picks per inch. After desizing, scouring, bleaching, drying and conditioning, the air permeability and light transmission properties of the fabric samples were determined. Regression analysis results showed statistically significant effect of the fabric ends, picks and warp linear density on both the fabric air permeability and light transmission. Correlation analysis was performed to analyze the relation between the fabric air permeability and light transmission. A linear equation was also formulated to find the fabric air permeability through transmission of light intensity. A fitted line plot between the air permeability and light transmission exhibited significant correlation with R-sq. value of 96.4%. The statistical models for the prediction of fabric air permeability and light transmittance were developed with an average prediction error of less than 7%.

Sharpless asymmetric dihydroxylation is an important reaction in the enantioselective synthesis of chiral vicinal diols that involves the treatment of alkene with osmium tetroxide along with optically active quinine ligand. Sharpless introduced this methodology after considering the importance of enantioselectivity in the total synthesis of medicinally important compounds. Vicinal diols, produced as a result of this reaction, act as intermediates in the synthesis of different naturally occurring compounds. Hence, Sharpless asymmetric dihydroxylation plays an important role in synthetic organic chemistry due to its undeniable contribution to the synthesis of biologically active organic compounds. This review emphasizes the significance of Sharpless asymmetric dihydroxylation in the total synthesis of various natural products, published since 2020.

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