Cotton is a major cash crop and backbone of the textile industry in Pakistan which is badly affected by sucking insects. Drought is an important abiotic factor in trichome development. The objective of the study was to determine the effects of drought on trichome density and length. Trichome density was measured in two ways, one through the scaling method and the other through counting the trichome density manually. The scaling method is qualitative grading while quantitative grading includes trichomecount in a card of optimized length. Three scales were finalized to classify leaves on the basis of trichomes which were counted in a specific area (0.25cm2) on abaxial side of the leaf. In drought stress, trichomes density and length were measured and compared to that in normal conditions. Trichome density varies from 12 to 56 in 0.25cm2 under drought stress. On the basis of correlation of trichome density with stomatal conductance, photosynthetic rate, PAR and transpiration ratio under drought and normal conditions, it was concluded that trichome density increased as a result of drought stress.

Nonrenewable energy resources deplete with the passage of time due to rapid increase in industrialization and population. Hence, countries worldwide are investing dearly in substitute energy resources like biofuel from miscellaneous set of feedstocks. Among the energy crops, sorghum serves as a model crop due to its drought tolerance, small genome size (730 Mb), high biomass, dry matter contents, quick growth, wide adaptability to diverse climatic and soil conditions and C4 photosynthesis. Sweet sorghum with high sugar content in stalk is an efficient feedstock for advanced biofuels and other bio-based products from sugars.However, high biomass sorghum has the utility as a feedstock for cellulosic biofuels. The enhanced yield of monomeric carbohydrates is a key to cheap and efficient biofuel production. The efficiency of lignocellulosic biofuels is compromised by recalcitrance to cell wall digestion, a trait that cannot be efficiently improved by traditional breeding. Therefore, scientists are looking for solutions to such problems in biomass crop genomes. Sorghum genome has been completely sequenced and hence this crop qualifies for functional genomics analysis by fast forward genetic approaches. This chapter documents the latest efforts on advancement of sorghum for biomass potential at morphological and molecular level by exploiting genomics approaches.

Sorghum is an important fodder crop with high biomass production potential all around the world including Pakistan. Genetic divergence was estimated among 208 sorghum genotypes of Pakistan by evaluating fourteen different quantitative traits for one year. High variability was reported in fresh biomass (35.60-629.12 g), dry biomass (23.41-367.72 g), flag leaf area index (37.61-407.39 cm 2), leaf area index (94.71-1061.74 cm 2) and plant height (106.14-298.27 cm). All the quantitative traits showed high broad sense heritability. The first three principal components (PCs) with Eigen value>1 shared 75.39% variability of traits among sorghum genotypes. Positive correlation was observed between plant height and days to maturity, whereas fresh and dry biomass had significant positive correlation with leaf area index, number of leaves per plant, flag leaf area index, days to maturity and 50% days to flowering. Un-weighted Pair-Group Method of Analysis (UPGMA) revealed 141 morphotypes. The germplasm was grouped in to seven classes based on homology. The genotype P-13-2013 gave the highest values for number of leaves/plant, stem thickness, leaf length, fresh biomass, dry biomass and flag leaf area index. The explored genetic potential of sorghum germplasm of Pakistan can be helpful for varietal improvement program. Moreover, the diverse set of genotypes can be screened through principal component analysis for structure and association mapping by using molecular markers.

The present research was conducted at the research area of the MNS-University of agriculture Multan Pakistan during kharif 2018, to determine the genetic variability for yield related traits of twenty-five maize (Zea mays L.) hybrids collected from International Maize and Wheat Improvement center (CIMMYT). The study was carried out in a randomized complete block design (RCBD) with two replications. Significantly variability (P≤0.01) among the hybrids were found for all yield related traits. Mean values for plant height were ranged from 82.61 to 223.72 (cm), ear height from 23.6 to 98.5 (cm), ear length from 9.8 to 21.8 (cm), number of ears from 1.005 to 1.85, cob weight from 67.63 to 179.3 (g), kernels per cob from 198.1 to 574.2, kernel rows per cob from 10 to 15.54, kernels per row 18.520 to 38.950, 100 grains weight from 18.3 to 34.4 (g) and grain yield per plant from 44.32 to 149.40 (g). Highest estimate of genotypic (GCV) along with phenotypic (PCV) coefficient of variations was recorded for ear height 43.07 45.13 %, plant height 30.20 and 33.23%, grain yield per plant 31.75 and 33.54 %, cob weight 27.46 and 29.34% and kernels per cob 24.13 and 25.13% respectively. Hybrid CZH132151 and CZH132150 performed better for yield related traits. All traits were significantly correlated with each other except number of ears per plant which was non-significantly correlated with most of the traits. The positive correlations suggest that the desired characters in these hybrids can be improved simultaneously in further maize breeding programs. Predicted on the results of current study, maize hybrid CZH132151 and CZH132150 could be suggested for commercial cultivation for the agro climatic condition of Multan.

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