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Onion is an economically important vegetable cultivated worldwide on a large scale. Liberal exchange of germplasm and frequent selection caused narrow genetic diversity in most crops, including onion. Thus, it is essential to estimate and understand genetic diversity before launching of any breeding program. The current study was conducted to explore genetic diversity among 39 short-day onion genotypes (indigenous and exotic).All the genotypes were evaluated for various phenotypic traits by using single nucleotide polymorphism (SNP) genotyping based on KASPar assays. Principal component analysis (PCA) was performed to determine the variability among genotypes. The four principal components with eigenvalue greater than 1 accounted for 67.5656% variability for quantitative traits, whereas first five principal components with eigenvalue greater than 0.7 accounted for 86.24% variation among the genotypes for qualitative traits. The principal component analysis identified diverse traits including bulb weight, bulb diameter, plant height, number of survived plants and vitamin C. These traits were further analyzed through ANOVA (Analysis of Variance) following augmented block design to describe genotypic variability for selected traits. Onion genotypes showed significant variation for bulb weight, bulb diameter and Vitamin C. Genotypic clustering based on PCA showed that 15 indigenous genotypes were clustered with exotic genotypes (14) while remaining indigenous genotypes (10) were distant. A total of 30 SNPs were used for assessment of genetic diversity out of these, 24 SNPs were detected with polymorphic loci (0.8%, heterozygosity), while only six markers were with monomorphic sites (0.2% heterozygosity). Subsequently, population structure analysis revealed three different populations indicating significant variability.Conclusively, a significant similarity between exotic and a group of indigenous genotypes indicates direct adoption of exotic genotypes or their sister lines. A further broadening of the genetic base is required and could be done by crossing distant genotypes.

Stripe rust is a continuous threat to wheat crop all over the world. It causes considerable yield losses in wheat crop every year. Continuous deployment of adult plant resistance (APR) genes in newly developing wheat cultivars is the most judicious strategy to combat this disease. Herein, we dissected the genetics underpinning stripe rust resistance in Pakistani wheat germplasm. An association panel of 94 spring wheat genotypes was phenotyped for two years to score the infestation of stripe rust on each accession and was scanned with 203 polymorphic SSRs. Based on D´ measure, linkage disequilibrium (LD) exhibited between loci distant up to 45 cM. Marker-trait associations (MTAs) were determined using mixed linear model (MLM). Total 31 quantitative trait loci (QTLs) were observed on all 21 wheat chromosomes. Twelve QTLs were newly discovered as well as 19 QTLs and 35 previously reported Yr genes were validated in Pakistani wheat germplasm. The major QTLs were QYr.uaf.2AL and QYr.uaf.3BS (PVE, 11.9%). Dissection of genes from the newly observed QTLs can provide new APR genes to improve genetic resources for APR resistance in wheat crop.

Over exploitation of Ground Water (GW) has resulted in lowering of water table in the Indus Basin. While waterlogging, salinity and seawater intrusion has resulted in rising of water table in Indus Basin. The sparse piezometer network cannot provide sufficient data to map groundwater changes spatially. To estimate groundwater change in this region, data from Gravity Recovery and Climate Experiment (GRACE) satellite was used. GRACE measures (Total Water Storage) TWS and used to estimate groundwater storage change. Net change in storage of groundwater was estimated from the change in TWS by including the additional components such as Soil Moisture (SM), Surface water storage (Qs) and snowpack equivalent water (SWE). For the estimation of these components Global Land Data Assimilation system (GLDAS) Land Surface Models (LSMs) was used. Both GRACE and GLDAS produce results for the Indus Basin for the period of April 2010 to January 2017. The monitoring well water-level records from the Scarp Monitoring Organization (SMO) and the Punjab Irrigation and Drainage Authority (PIDA) from April 2009 to December 2016 were used. The groundwater results from different combinations of GRACE products GFZ (GeoforschungsZentrum Potsdam) CSR (Center for Space Research at University of Texas, Austin) JPL (Jet Propulsion Laboratory) and GLDAS LSMs (CLM, NOAH and VIC) are calibrated (April 2009-2014) and validated (April 2015-April 2016) with in-situ measurements. For yearly scale, their correlation coefficient reaches 0.71 with Nash-Sutcliffe Efficiency (NSE) 0.82. It was estimated that net loss in groundwater storage is at mean rate of 85.01 mm per year and 118,668.16 Km3 in the 7 year of study period (April 2010-Jan 2017). GRACE TWS data were also able to pick up the signals from the large-scale flooding events observed in 2010 and 2014. These flooding events played a significant role in the replenishment of the groundwater system in the Indus Basin. Our study indicates that the GRACE based estimation of groundwater storage changes is skillful enough to provide monthly updates on the trend of the groundwater storage changes for resource managers and policy makers of Indus Basin.

Deforestation is a common threat to the environment that has a substantial impact on the forest’s distribution across territorial boundaries. It is simply defined as the loss of forest cover, which most commonly occurs as a result of deforestation for various reasons. Pakistan is among those countries which have a very high deforestation rate. This paper analyzes the various socioeconomic factors which cause deforestation in northern Pakistan and the existing economic incentive tools for reducing deforestation. Data collected from 602 respondents were analyzed using descriptive statistics and a logistic regression model, while the Likert scale was used to determine the mean socioeconomic factor score encouraging deforestation and the economic incentives used to reduce deforestation. Gender distributions showed that the majority (65.9%) of the respondents were male while 34.1% were female. On family size, the majority of the respondents (66.8%) had a family size of 5–8. On age, between 21–25 years (46.0%) recorded the highest number. The average age of the respondents was 24 years. Educationally, 13.8% had a master’s education, 11.1% a bachelor’s education, 4.3% no formal education, 5.6% a higher education level, meaning master’s or PhD students, 56.1% had a primary education, and 9.0% had a secondary education. On occupation, the majority (50.4%) of the respondents were involved in farming as their main occupation. On income, the major income recorded a mean of 25,000 net, while the minor income recorded a mean of 15,500 net. Setting the forest ablaze, increasing farming activities, low level of literacy, increasing timber mafia, growing population, and poverty were the socioeconomic factors found. The economic incentives listed were for forest crop subsidies, an enhanced system of taxes on exploited forest products, the acquisition of well-monitored hunting licenses, alternative job opportunities, credit provision, and a limited ban on round log exports. The results of the logit regression established that rewarding socioeconomic factors were statistically significant variables at (p < 0.05). Conclusively, if adequately controlled and applied, economic incentives can be an important instrument for reducing deforestation. Therefore, deforestation activities cannot be entirely eradicated but they can be reduced to the barest minimum by properly enforcing forest policies in terms of efficient forest policing. The goals of this study are to help with the implementation of appropriate policies and decision-making in forest management, as well as to provide a foundation for future scenario analysis of deforestation potential or to investigate potential environmental and human implications.

Resistance breeding is comparatively less effective, tedious and unremitting process because the pathogens keep on mutating and generate new races. The developed material fell susceptible to these newly evolved races. Even then the breeders are triumphant in shielding most of the crops under cultivation around the globe from fungal diseases. This review summarizes the knowledge about genetic pathways involved in plant disease resistance mechanism, plant-pathogen interaction, production of phytoalexins/secondary metabolites and other pathogenesis related proteins and their interactions in plant defense response.

The Bcl-2-associated athanogene (BAG) proteins are involved in the regulation of Hsp70/HSC70 in animals. There are six BAG genes in human that encode nine isoforms with different subcellular locations. Arabidopsis thaliana is reported to contain seven BAG proteins. We searched BAG proteins in Oryza sativa using profile-sequence (Pfam) and profile-profile (FFAS) algorithms and found six homologs. The BAG protein family in O. sativa can be grouped into two classes based on the presence of other conserved domains. Class I consists of four OsBAG genes (1 to 4) containing an additional ubiquitin-like domain, structurally similar to the human BAG1 proteins and might be BAG1 orthologs in plants. Class II consists of two OsBAG genes (5 and 6) containing calmodulin-binding domain. Multiple sequence alignment and structural models of O. sativa BAG proteins showed conservation of surface charge (except OsBAG5) and critical residues for the binding of BAG domain to Hsp70 nucleotide binding domain (NB). Meta analysis of microarray data showed that OsBAG genes are up or down regulated under different stresses (biotic and abiotic). Data obtained from real-time PCR of OsBAG genes under heat stress showed that maximum induction in the expression of all the genes occurred after one hour exposure to heat stress, while reduction in the expression was observed in the following time course and ultimately returned to the basal level at 24 h treatment. These results suggest that OsBAG genes might play important role at the onset of heat stress. A further detailed study may explore the exact function of the members of this gene family and help to make understanding of programmed cell death (PCD) mechanism in plants. Key words : Rice, ubiquitin-like domain, nucleotide-binding domain, real-time PCR.