The development of high-yielding heat-tolerant cotton cultivars harboring plastic phenotypes across warming climatic regions is prime objectives of today’s cotton breeding programs. We evaluated eight parents and 15 F1 hybrids under normal and heat stress conditions. Agronomic and biochemical characters were analyzed using standard least square, correlation, principal component analysis (PCA), and hierarchical clustering. The results explained a significant reduction in all traits except hydrogen peroxide contents, catalase, and peroxidase activities with a prominent increase under heat stress. A significant positive correlation was observed among all agronomic and biochemical traits. POD was found to have a maximum positive correlation with CAT (0.947) and minimum with boll weight (0.050). PCA showed first two components accounting for 78.64% of the total variation, with 55.83% and 22.80% of the total variation, respectively. Based on multivariate analyses methods 23 genotypes have been placed in 3 groups: tolerant (cluster-3), moderately tolerant (cluster-2), and susceptible (cluster-1). In a general perspective hybrids have better performance across normal and heat stress supports the idea of hybrid adaptability across stress environments. In specific FH-458 × FH-313 cross performed best across both conditions for yield and physiological traits. Hence, the generated information from the present study would support breeders in developing heat-resilient cultivars to endure the prevailing extreme environmental conditions.

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ABSTRACT. Drought stress is limiting global crop production more seriously than ever because of rapid change in global climate. Present investigations were made with a view to understand the traits which can be used as selection criteria for drought tolerance in maize at seedling stage. For this purpose twenty-five maize inbred lines were evaluated under water deficit conditions for traits like fresh shoot weight, fresh shoot length, fresh root length, fresh root weight, leaf venation, stomatal frequency and epidermal cell size. Significant differences were found among the genotypes for various physio-genetic traits. The genotypes 20P2-1, L5-1, 150P2-1, 70NO2-2, 150P1 and L7-2 were found good performer and may be exploited for developing drought tolerant synthetics and hybrids. Fresh shoot length and fresh root weight found overall direct and indirect contributor in fresh shoot weight and they were positive and significantly correlated with fresh shoot weight. Stomatal frequency and epidermal cell size had significantly decreasing direct and indirect effects on fresh shoot weight and significant genetic correlation with it. These results suggested that fresh shoot length and fresh root weight (Increased) stomatal frequency and epidermal cell size (decreased) might be used as selection criterion while selection for high fresh shoot yield under drought conditions.

Acacia nilotica is an important agroforestry specie, which is used in both compact and linear forms. The objective of the current study was to evaluate the effect of compost on the growth performance and biomass production of A. nilotica. Completely randomized design (CRD) was used to analyze the variations among several growth morphological traits. Two parallel trials, pot trial (seedlings), field trial (saplings) were conducted simultaneously. Compost and litter mixture were applied in mentioned trials. Following treatments were used: T0 – control; T1 - 25% of compost and 75% of nursery soil; T2 - mixture of 50% nursery soil and 50% compost; T3 - mixture of 75% compost and 25% of nursery soil; T4 - where 100% compost was applied. Increase in plant growth was observed with the increases in the amount of compost mixture. In field trial maximum plant height, shoot length, root length, rootshoot ratio and biomass production was observed when 100% compost level was applied, while minimum was observed without any compost appli-cation. In pot trials, the maximum plant height, rootshoot ratio and biomass production was recorded when 75% compost level was applied. Overall, Acacia performed better with 100% of compost application in field trail and 75% of compost application in pot trial. The results of this study demonstrated the positive effects of compost on the growth of Acacia. The seedling development was improved considerably with different levels having greater percentage of organic fertilizer and it was concluded that compost improves soil fertility and it should be used as organic fertilizer in farming and forestry practices for improving crop growth and yield.

Plants generally showed variation in their response to changing environment. Fifteen genotypes were tested at five locations in Pakistan in the Kharif season 2006 to study their yield stability. Pooled analysis of variance and stability analysis were performed. The genotype (G) x environment (E) interaction and both variance due to genotypes and environments were significant. The partitioning of G x E interaction into linear and non-linear components indicated that both predictable and unpredictable components shared the interaction. Three stability parameters were computed to judge the stable and superior genotype. On the basis of these parameters, the top yielding genotype '2 (check) CGM-504' exhibited the stable performance over all five locations. Results also showed that the genotypes; BRM-288, NCM-257-2 and BRM-286 gave higher yield. But their performance was unstable due to high deviation from regression. Seven genotypes NCM-252-7, 2CMG-504, C1/95-3/45, BRM-286, BRM-288, NCM-257-2 and M-8 produced more grain yield than average yield. On the basis of results, 2CMG-504 was the most suitable and desirable genotype which showed stable yields at different sites.