Identifying adopted Green Super Rice (GSR) under different agro-ecological locations in Pakistan is crucial to sustaining the high productivity of rice. For this purpose, the multi-location trials of GSR were conducted to evaluate the magnitude of genetic variability, heritability, and stability in eight different locations in Pakistan. The experimental trial was laid out in a randomized complete block (RCB) design with three replications at each location. The combined analysis of variance (ANOVA) manifested significant variations for tested genotypes (g), locations (L), years (Y), genotype × year (GY), and genotype × location (GL) interactions revealing the influence of environmental factors (L and Y) on yield traits. High broad-sense heritability estimates were observed for all the studied traits representing low environmental influence over the expression of traits. Noticeably, GSR 48 showed maximum stability than all other lines in the univariate model across the two years for grain yield and related traits data. Multivariate stability analysis characterized GSR 305 and GSR 252 as the highest yielding with optimum stability across the eight tested locations. Overall, Narowal, Muzaffargarh, and Swat were the most stable locations for GSR cultivation in Pakistan. In conclusion, this study revealed that G×E interactions were an important source of rice yield variation, and its AMMI and biplots analysis are efficient tools for visualizing the response of genotypes to different locations.

The wheat plant requires elevated phosphorus levels for its normal growth and yield, but continuously depleting non-renewable phosphorus reserves in the soil is one of the biggest challenges in agricultural production worldwide. The Phosphorus Starvation Tolerance 1 (PSTOL1) gene has been reported to play a key role in efficient P uptake, deeper rooting, and high yield in rice. However, the function of the PSTOL1 gene in wheat is still unclear. In this study, a total of 22 PSTOL1 orthologs were identified in the wheat genome, and found that wheat PSTOL1 orthologs are unevenly distributed on chromosomes, and these genes were under strong purifying selection. Under different phosphorus regimes, wheat PSTOL1 genes showed differential expression patterns in different tissues. These results strengthen the classification of Pakistan-13 as a P-efficient cultivar and Shafaq-06 as a P-inefficient cultivar. Phenotypic characterization demonstrated that Pakistan-13 wheat cultivar has significantly increased P uptake, root length, root volume, and root surface area compared to Shafaq-06. Some wheat PSTOL1 orthologs are co-localized with phosphorus starvation’s related quantitative trait loci (QTLs), suggesting their potential role in phosphorus use efficiency. Altogether, these results highlight the role of the wheat PSTOL1 genes in wheat P uptake, root architecture, and efficient plant growth. This comprehensive study will be helpful for devising sustainable strategies for wheat crop production and adaptation to phosphorus insufficiency.

Receptor-like protein kinase1 (RPK1) genes play crucial roles in plant growth and development processes, root architecture, and abiotic stress regulation. A comprehensive study of the RPK1 gene family has not been reported in bread wheat (Triticum aestivum). Here, we reported the genome-wide identification, characterization, and expression patterns of the RPK1 gene family in wheat. Results confirmed 15 TaRPK1 genes, classified mainly into three sub-clades based on a phylogenetic tree. The TaRPK1 genes were mapped on chromosomes 1–3 in the respective A, B, and D genomes. Gene structure, motif conservation, collinearity prediction, and synteny analysis were carried out systematically. A Gene ontology study revealed that TaRPK1 genes play a vital role during molecular and biological processes. We also identified 18 putative miRNAs targeting TaRPK1 genes, suggesting their roles in growth, development, and stress responses. Cis-Regulatory elements interpreted the presence of light-related elements, hormone responsiveness, and abiotic stress-related motifs in the promoter regions. The SWISS_MODEL predicted the successful models of TaRPK1 proteins with at least 30% identity to the template, a widely accepted threshold for successful modeling. In silico expression analysis in different tissues and stages suggested that TaRPK1 genes exhibited the highest expression in root tissues. Moreover, qRT-PCR further validated the higher expression of TaRPK1 genes in roots of drought-tolerant varieties compared to the drought-susceptible variety. Collectively, the present study renders valuable information on the functioning of TaRPK1 genes in wheat that will be useful in further functional validation of these genes in future studies.

Background: Rice is the staple food for more than half of the world's population. Rice cultivation needs expansion to meet the increasing food demands across the globe. Genetic diversity is desired for crop breeding because it serves as the backbone for improving cultivars. The process of domestication and modern plant breeding technologies applied to rice has contributed to the erosion of genetic diversity. Current breeding programs have extensively shaped the genetic diversity of elite rice cultivars to no small extent. Results: We explored the genetic diversity of traditional landraces and improved cultivars by inspecting the whole genome SNP markers of 20 rice accessions. We found a higher number of genetic variations (76.70%) and observed heterozygosity (0.024) in landraces than improved cultivars. The principal component analysis also revealed the higher genetic diversity among the landraces. While population structure based on the phylogenetic tree suggested the population's structure according to rice subspecies. The genetic diversity parameter, FST, was applied to estimate the genetic differentiation of rice, which revealed week genetic differentiation (0.121) and nucleotide diversity (0.314) in modern rice cultivars. Genome-wide genetic differentiation (FST) analysis identified the two domesticated genes: Kala4 (pericarp color) and Ghd7 (heading date), and eight improvement genes: Sd1, Ghd8, GW2, NRT1.1b, GW6a, and Hd3a, that coincide with the candidate selective sweeps. Inbreeding depression (0.68617) among the modern cultivars suggests no genetic gain in future breeding efforts and compels exotic material utilization in the breeding programs. Conclusion: These findings demonstrate that modern cultivars have a narrow genetic base compared to landraces. Therefore, exploring the genome of landraces at a large scale to identify the genes responsible for stability and adaptation to abiotic stresses can help design varieties that can survive vulnerable climates.

Optimum growing temperature is necessary for maximum yield-potential in any crop. The global atmospheric temperature is changing more rapidly and irregularly every year. High temperature at the flowering/reproductive stage in rice causes partial to complete pollen sterility, resulting in significant reduction in grain yield. Green Super Rice (GSR) is an effort to develop an elite rice type that can withstand multiple environmental stresses and maintain yield in different agro-ecological zones. The current study was performed to assess the effect of heat stress on agronomic and physiological attributes of GSR at flowering stage. Twenty-two GSR lines and four local checks were evaluated under normal and heat-stress conditions for different agro-physiological parameters, including plant height (PH), tillers per plant (TPP), grain yield per plant (GY), straw yield per plant (SY), harvest index (HI), 1000-grain weight (GW), grain length (GL), cell membrane stability (CMS), normalized difference vegetative index (NDVI), and pollen fertility percentage (PFP). Genotypes showed high significant variations for all the studied parameters except NDVI. Association and principal component analysis (PCA) explained the genetic diversity of the genotypes, and relationship between the particular parameters and grain yield. We found that GY, along with other agronomic traits, such as TPP, SY, HI, and CMS, were greatly affected by heat stress in most of the genotypes, while PH, GW, GL, PFP, and NDVI were affected only in a few genotypes. Outperforming NGSR-16 and NGSR-18 in heat stress could be utilized as a parent for the development of heat-tolerant rice. Moreover, these findings will be helpful in the prevention and management of heat stress in rice.