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The stable performance of cultivars is a prerequisite for enhanced yield production to ensure food security. Identification of the stable yield performing genotype is the necessity of any breeding program to improve the livelihood of farmers. The present study was performed to evaluate the genotype and environment interaction of 22 green super rice (GSR) genotypes at eight different locations in Pakistan. The genotype × environment interaction was assessed by univariate and multivariate analysis for yield and yield-related traits. The harvest index, grain yield, total biomass, and straw yield showed higher variation among the genotypes, evaluated by PCA biplot analysis. The multiplicative interactions (AMMI) analysis of variance was found significant among genotypes, environments (locations), and genotype × environment interaction (G × E). The AMMI model demonstrated that genotypes S8 and S16 performed best across the environments, whereas, genotypes S18, S17, S15, and S5 revealed stable performance across the environments. The two-dimensional GGE biplot explained 56.74% variation for all studied traits across the environments. The GGE biplot results indicated that genotypes S13, S15, S18, S1, and S5 showed stable yield performance across the environments, whereas genotypes S16 and S8 demonstrated the high yield genotypes with low stability. Based on these multivariate analyses, genotype S5 depicted stable performance across the environments, while genotypes S8 and S16 were high yielding with low stability across the environments. Among the environments, Islamabad, Muzaffargarh, and Sahiwal are the most suitable environments for GSR genotypes cultivation. These results could be helpful in the selection of genotypes and will be recommended for commercial cultivation in the future. [ABSTRACT FROM AUTHOR]

Introduction of Green Super Rice (GSR) in Pakistan aims to develop high-yielding, quality and climate-resilient rice cultivars. In this regard, the morphological evaluation of 552 GSR lines for yield and related traits were studied using Alpha Lattice (LS) design with three replications. The phenotypic variability of GSR lines revealed significant mean sum of squares (p<0.01) for all the studied traits. On average, GSR lines showed maximum trait performances for days to flowering, days to ripening, days to maturity, tillers per plant, total biomass, straw yield per plant, grain yield per plant, and harvest index compared with the basmati and non-basmati rice. Relatively high heritability was estimated for days to flowering (97.8%), days to ripening (89%), days to maturity (98.5%), plant height (76.7%), and panicle length (78.8%), whereas, moderate heritability coupled with genetic advance was recorded for tillers per plant (41%), grain yield per plant (43%) and harvest index (53%). Correlation analysis revealed that grain yield per plant had strong and positive correlation with other yield-related traits; tillers per plant (r=0.51**), total biomass (r=0.48**), harvest index (r=0.32**) and straw yield per plant (r=0.28**). Moreover, principal components analysis (PCA) suggested that grain yield per plant, straw yield per plant and total biomass are critical traits that contributed significantly to the total variation in the GSR population. In conclusion, the GSR traits with superior heritability and yield performances are potentially valuable resources for developing high and stable rice cultivars in Pakistan. [ABSTRACT FROM AUTHOR]

Abiotic stresses, including drought, salinity, temperature, and heavy metals, pose a major challenge for crop production and cause substantial yield reduction worldwide. Breeding tolerant cultivars against these abiotic stresses is the most sustainable and eco-friendly approach to cope with this challenge. Advances in genome editing technologies provide new opportunities for crop improvement by employing precision genome engineering for targeted crop traits. However, the selection of the candidate genes is critical for the success of achieving the desired traits. Broadly speaking, these genes could fall into two major categories, structural and regulatory genes. Structural genes encode proteins that provide stress tolerance directly, whereas regulatory genes act indirectly by controlling the expression of other genes involved in different cellular processes. Additionally, cis -regulatory sequences are also vital for achieving stress tolerance. We propose targeting of these regulatory and/or structural genes along with the cis -regulatory sequences via the clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 (Cas9) system as a robust, efficient, and practical approach for developing crop varieties resilient to climate change. We also discuss the possibility of creating novel quantitative trait loci for abiotic stress tolerance via the CRISPR/Cas-mediated targeting of promoters. It is hoped that these genome editing tools will not only make a significant contribution towards raising novel plant types having tolerance to multiple abiotic stresses but will also aid in public acceptance of these products in years to come. This article is an attempt to critically evaluate the suitability of available tools and the target genes for obtaining plants with improved tolerance to abiotic stresses. [ABSTRACT FROM AUTHOR]

Drought causes osmotic stress and rapidly triggers abscisic acid (ABA) accumulation in plants. The roles of various ABA receptors in drought tolerance and molecular mechanisms regulating ABA receptor stability needs to be elucidated. Here, we report that Arabidopsis plants overexpressing PYL9, one of the 14 pyrabactin resistance (PYR)/pyrabactin resistance-like (PYL)/regulatory component of ABA receptors (RCAR) family ABA receptors, gained drought tolerance trait. Osmotic stress induced accumulation of the PYL9 protein, which was regulated by the 26S proteasome. PYL9 interacted with two highly homologous plant U-box E3 ubiquitin ligases PUB22 and PUB23. In the cell-free degradation assay, the degradation of GST-PYL9 was accelerated in protein extract from plants overexpressing PUB22 but slowed down in protein extract from the pub22 pub23 double mutant. The in vivo decay of Myc-PYL9 was significantly reduced in the pub22 pub23 double mutant as compared with the wild-type. Additionally, PUB22 also interacted with other ABA receptors such as PYL5, PYL7 and PYL8. Considering the improved drought tolerance in the pub22 pub23 double mutant in previous studies, our results suggest that PUB22 and PUB23 negatively regulate drought tolerance in part by facilitating ABA receptors degradation. [ABSTRACT FROM AUTHOR]

Introduction: Phytic acid (PA) is an important antinutrient agent present in cereal grains which reduces the bioavailability of iron and zinc in human body, causing malnutrition. Inositol pentakisphosphate 2- kinase 1 ( IPK1 ) gene has been reported to be an important gene for PA biosynthesis., Objective: A recent genome editing tool CRISPR/Cas9 has been successfully applied to develop biofortified rice by disrupting IPK1 gene, however, it remained a challenge in wheat. The aim of this study was to biofortify wheat using CRISPR/Cas9., Methods: In this study, we isolated 3 TaIPK1 homeologs in wheat designated as TaIPK1.A , TaIPK1.B and TaIPK1.D and found that the expression abundance of TaIPK1.A was stronger in early stages of grain filling. Using CRISPR/Cas9, we have disrupted TaIPK1.A gene in cv. Borlaug-2016 with two guide RNAs targeting the 1st and 2nd exons., Results: We got several genome-edited lines in the T 0 generation at frequencies of 12.7% and 10.8%. Sequencing analysis revealed deletion of 1-23 nucleotides and even an addition of 1 nucleotide in various lines. Analysis of the genome-edited lines revealed a significant decrease in the PA content and an increase in iron and zinc accumulation in grains compared with control plants., Conclusion: Our study demonstrates the potential application of CRISPR/Cas9 technique for the rapid generation of biofortified wheat cultivars., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Authors. Published by Elsevier B.V. on behalf of Cairo University.)

Drought causes osmotic stress and rapidly triggers abscisic acid (ABA) accumulation in plants. The roles of various ABA receptors in drought tolerance and molecular mechanisms regulating ABA receptor stability needs to be elucidated. Here, we report that Arabidopsis plants overexpressing PYL9, one of the 14 pyrabactin resistance (PYR)/pyrabactin resistance-like (PYL)/regulatory component of ABA receptors (RCAR) family ABA receptors, gained drought tolerance trait. Osmotic stress induced accumulation of the PYL9 protein, which was regulated by the 26S proteasome. PYL9 interacted with two highly homologous plant U-box E3 ubiquitin ligases PUB22 and PUB23. In the cell-free degradation assay, the degradation of GST-PYL9 was accelerated in protein extract from plants overexpressing PUB22 but slowed down in protein extract from the pub22 pub23 double mutant. The in vivo decay of Myc-PYL9 was significantly reduced in the pub22 pub23 double mutant as compared with the wild-type. Additionally, PUB22 also interacted with other ABA receptors such as PYL5, PYL7 and PYL8. Considering the improved drought tolerance in the pub22 pub23 double mutant in previous studies, our results suggest that PUB22 and PUB23 negatively regulate drought tolerance in part by facilitating ABA receptors degradation., Competing Interests: The authors declare no conflict of interest.

Objective: To assess the development of UTI in paediatric patients, presented to OPD with urolithiasis. To ascertain what general parameters are associated with UTI, and examine specific characteristics of the calculi., Method: It was a retrospective study. Files of paediatric patients from July 2000 to December 2004 were reviewed. Only those patients with calculi and absent UTI and upto 5 years age were studied. All files of patients, primarily presenting with UTI, and those with documented urological procedures prior to UTI occurrence, were excluded from the study. Ultrasound and X-ray techniques were used to determine stone size and location. Collected urine samples were screened for UTI; organisms were isolated and cultured using Cystine Lactose Electrolyte Deficient (CLED) culture medium., Result: A total of 149 patients were studied. The mean age was 3.05 +/- 1.25 years, [77.2 %] were males [22.8%] females. Urinary tract infection [UTI] was found in 37.6% cases. Age status was significantly associated with UTI [p=0.008] along with the anatomical location [p=0.021]. The most common organism found on our culture plate of UTI positive patients was E. coli (21.4%). Bacteria were most sensitive to aminoglycoside group [16%] of antibiotics., Conclusion: We found a significant association between age, anatomical location of stones and UTI. These factors should be considered in paediatric patients to prevent UTI and its complications.