Cotton is classified as moderately salt tolerant crop with salinity threshold level of 7.7 dS m-1. Salinity is a serious threat for cotton growth, yield and fiber quality. The sensitivity to salt stress depends upon growth stage and type of salt. Understanding of cotton response to salinity, its resistance mechanism and looking into management techniques may assist in formulating strategies to improve cotton performance under saline condition. The studies have showed that germination, emergence and seedling stages are more sensitive to salinity stress as compared to later stages. Salt stress results in delayed flowering, less fruiting positions, fruit shedding and reduced boll weight which ultimately affect seed cotton yield. Depressed activities of metabolic enzymes viz: acidic invertase, alkaline invertase and sucrose phophate synthase lead to fiber quality deterioration in salinity. Excessive sodium exclusion or its compartmentation is the main adaptive mechanism in cotton under salt stress. Up regulation of enzymatic and non-enzymatic antioxidants genes offer important adaptive potential to develop salt tolerant cotton varieties. Seed priming is also an effective approach for improving cotton germination in saline soils. Intra and inter variation in cotton germplasm could be used to develop salt tolerant varieties with the aid of marker assisted selection. Furthermore, transgenic approach could be the promising option for enhancing cotton production under saline condition. It is suggested that future research may be carried out with the combination of conventional and advance molecular technology to develop salt tolerant cultivars.

Plant stresses causing accumulation of reactive oxidative species (ROS) are scavenged by effective antioxidant defense systems. Therefore, the present study performed genome-wide identification of superoxide dismutase (SOD) and glutathione peroxidase (GPX) gene families in cultivated and wild soybeans, and 11 other legume species. We identified a total of 101 and 95 genes of SOD and GPX, respectively, across thirteen legume species. The highest numbers of SODs and GPXs were identified in cultivated (Glycine max) and wild (Glycine soja). A comparative phylogenetic study revealed highest homology among the SODs and GPXs of cultivated and wild soybeans relative to other legumes. The exon/intron structure, motif and synteny blocks were conserved in both soybean species. According to Ka/Ks, purifying the selection played the major evolutionary role in these gene families, and segmental duplication are major driving force for SODs and GPXs expansion. In addition, the qRT-PCR analysis of the G. max and G. soja SOD and GPX genes revealed significant differential expression of these genes in response to oxidative, drought and salinity stresses in root tissue. In conclusion, our study provides new insights for the evolution of SOD and GPX gene families in legumes, and provides resources for further functional characterization of these genes for multiple stresses.

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Grain yield in wheat is the resultant of several plant attributes. It is very important to assess heritable variation involved in the inheritance of these attributes in addition to find the best combining genotypes. For this purpose, the present study involving 5 × 5 full diallel analysis was performed. Twenty F 1 hybrids along with their parents (9797, 9801, 9802, were planted in field using randomized complete block design (RCBD) with three replications in the research area of Department of Plant Breeding and Genetics, University of Agriculture, Faisalabad during 2015-2016. Plant characters like plant height, flag leaf area, spike length, No. of fertile tillers per plant, No. of grains per spike, No. of spikelets per spike, 1000 grain weight and grain yield per plant were studied in this experiment. Mean squares due to general combining ability (GCA) were highly significant for all the traits except for spike length for which GCA effects were significant. Mean squares due to specific combining ability (SCA) and reciprocal combining ability (RCA) were highly significant for all the characters studied. GCA variance was higher than the SCA variance for spike length and No. of grains per spike exhibiting the predominant role of additive genetic variation in the inheritance of these traits. However, for the characters like plant height, flag leaf area, No. of fertile tillers per plant, No. of spikelets per spike, 1000 grain weight and grain yield per plant, the value of SCA variance was higher than the value of GCA variance showing non additive gene action for these How to cite this paper: Parveen, N., Kanwal, A., Amin, E., Shahzadi, F., Aleem, S., Tahir

Plants coevolved with their antioxidant defense systems, which detoxify and adjust levels of reactive oxygen species (ROS) under multiple plant stresses. We performed whole-genome identification of ascorbate peroxidase (APX) and catalase (CAT) families in cultivated and wild soybeans. In cultivated and wild soybean genomes, we identified 11 and 10 APX genes, respectively, whereas the numbers of identified CAT genes were four in each species. Comparative phylogenetic analysis revealed more homology among cultivated and wild soybeans relative to other legumes. Exon/intron structure, motif and synteny blocks are conserved in cultivated and wild species. According to the Ka/Ks value, purifying selection is a major force for evolution of these gene families in wild soybean; however, the APX gene family was evolved by both positive and purifying selection in cultivated soybean. Segmental duplication was a major factor involved in the expansion of APX and CAT genes. Expression patterns revealed that APX and CAT genes are differentially expressed across fourteen different soybean tissues under water deficit (WD), heat stress (HS) and combined drought plus heat stress (WD + HS). Altogether, the current study provides broad insights into these gene families in soybeans. Our results indicate that APX and CAT gene families modulate multiple stress response in soybeans.

Cauliflower is a cool-season crop and temperature plays a critical role in curd induction. As on the basis of temperature requirement they are classified into early, mid and late season groups. However, most of the genotypes require an optimum temperature of 20-25

C auliflower (Brassica oleracea L. Var. botrytis) is a cool-season vegetable and is mostly cultivated for its white curd. It evolved from wild cabbage (Brassica oleracea L. 2n=18, CC), known as cole worts, through mutation, selection, and adaptation (Purugganan et al., 2000). Cauliflower was firstly originated in Cyprus and then was moved to other regions such as Syria,

| Seed rate is one of the most pivotal factors that significantly impact grain quality and yield in wheat. In wheat-based crop production system, it can be easily managed. An indiscrimination in seeding rate can lead to higher production cost but will also result in decline of crop yield and quality. Hence, the present experiment was designed to establish the optimal seeding density of three different wheat genotypes (Fatehjang-2016, Dharabi-11 and 16FJ17) of the Barani Areas to attain maximum economic yield. The research experiment was managed in split amidst the cropping season of Rabi 2019-20; one at the laboratory by growing three diverse genotypes of wheat at four different levels of seeding densities in pots and the other at field area of Barani Agricultural Research Station, Fateh Jang at four discrete levels of seeding density of 80, 100, 120 and 140 kg ha -1 , respectively. The experiment was laid down using a RCBD with three replication and four treatments. Different seed rates and genotypes significantly affected all plant traits except days to 50% heading, plant height and germination percentage. Contrarily, the interactive effect of genotype and seeding rate on all growth and yield attributes was found non-significant. Whereas, seeding density of 120 kg ha -1 exhibited more germination percentage (85 %), shoot length (11.57 cm), coleoptile length (3.97 cm), days to 50% heading (130), plant height (110 cm), nodes per stem (5.0), 1000 grain weight (49.53 g), grain per spike (41.0), days to maturity (172.67) and grain yield (3755 kg ha -1 ) in Fatehjang-2016. Whereas Dharabi-11 showed maximum root length (17.64 cm) and tiller count (405.67 m -2 ) at same level of seeding density. In contrast, 16FJ17 stood second in all parameters except root length and number of tillers m -2 . The value for grain per spike (40.0) and shoot length (10.55 cm) is at par with Fatehjang-2016 and Dharabi-11, respectively at 120 kg ha -1 of seeding level. It is evident from the results that wheat variety Fatehjang-2016 can effectively be planted at an optimum seed rate of 120 kg ha -1 for general cultivation and better economic returns in Barani Areas of Pakistan, provided all the agronomic and crop management practices must be kept optimum.