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Water stress is one of the major environmental constraints on wheat grain yield worldwide. One way to overcome this limitation is to evolve genetically stress-tolerant wheat genotypes that produce sustainable grain yields in water-scarce conditions. A field experiment was carried out to investigate the genetic diversity of 34 advanced wheat genotypes (Triticum aestivum L.) and two commercial check varieties (Khirman and TD-1) for grain yield and yield-associated agronomic traits in moisture stress (MS) and well-watered (WW) conditions. Plants were grown in residual moisture in rice fallow land in rainfed conditions without supplementary irrigation, i.e., MS conditions, while two rounds of irrigations were applied for the WW control conditions. Analysis of variance indicated a highly significant (p < 0.05) variation among genotypes for all the observed agronomic traits in MS and WW conditions. In the MS group, the exotic line IBWSN-1010, mutant line MASR-64, and doubled haploid line DH-12/7 produced the highest grain yield compared to all the contesting wheat genotypes, including check varieties. Grain yield per plot was positively correlated (r = 0.93) with biological yield per plot in MS conditions. Principal component analysis showed total variations of 21.9%, 20.4%, and 10.1% explained by PC-1, PC-2, and PC-3 in MS, and 22.9%, 14.8%, and 12.1% for PC-1, PC-2, and PC-3 in WW conditions. Our study provides valid information for the selection of newly evolved wheat genotypes and will be useful in future breeding programs. [ABSTRACT FROM AUTHOR]

The wheat variety NIA-Shaheen (CIM-04-10) has high grain yield and modern plant architecture. It has wide adaptability, increased tiller production, bold grains, high starch and protein content, and good tolerance to disease and environmental stresses, particularly water stress. NIA-Shaheen has high yield potential (7184 kg ha-1). [ABSTRACT FROM AUTHOR]

The wheat crop remains vulnerable to all three rust diseases (leaf rust, stem rust and yellow rust) caused byPucciniaspp. according to the prevalence of the pathogen in different wheat-growing areas worldwide. Stripe rust or yellow rust caused byPuccinia striiformisf. sp.triticiis the most significant rust pathogen which prefers cool, moist areas and highlands. The pathogen is recognised as responsible for huge production losses in wheat. Genetic variation in pathogen makes its control difficult. Therefore, resistance against all the races of the pathogen known as durable or race-non-specific resistance is preferred. The present study was carried out to identify durable resistance against stripe rust in selected wheat cultivars from Pakistan through seedling testing, field evaluation at adult stage, morphological marker studies and marker-assisted selection. Results revealed that 4% of the cultivars were resistant at the seedling stage while the rest were susceptible or intermediate. To confirm their field resistance, the same cultivars were evaluated under field conditions at Cereal Crops Research Institute Pirsabak (located in Khyber Pakhtunkhwa, KP) a hot spot of stripe rust in Pakistan. Observations exhibited that at the adult stage 4% of the cultivars were resistant, 70% intermediate or moderately resistant while the others were highly susceptible. Leaf tip necrosis was observed in 30% of the cultivars. Wheat cultivars showing susceptibility at the seedling stage were highly to moderately resistant at adult stage showing durable resistance. For further validation, morphological markers were also observed in cultivars indicating the presence ofYr18/Lr34gene. Eleven cultivars (C-518, Mexipak, Kohinoor-83, Faisalabad-83, Zardana-93, Shahkar-95, Moomal-2002, Wattan-94, Pasban-90, Kiran-95, and Haider-2000) were identified, having durable or race non-specific resistance against stripe rust. These cultivars can further be utilised in wheat breeding programmes for deploying durable resistance to attain long lasting control against stripe rust. [ABSTRACT FROM AUTHOR]

Polyethylene glycol (PEG-6000) is often used for the early establishment screening of the wheat genotypes against drought stress conditions. A collection of twenty-one newly developed bread wheat genotypes (developed through conventional and mutational breeding techniques) and four commercial drought tolerant check varieties were included in screening at seedling stage under three treatments of PEG-6000; T1 (0.5 MPa) and T2 (0.75 MPa) along with control T3 (distill water only). Three important early growth establishment traits like germination percentage, root length and shoot length of the wheat genotypes were observed. Significant variation among genotypic means regarding the observed traits was recorded at both the treatments. Wheat genotypes performance including check varieties for germination percentages was recorded as T1 (86.1%), T2 (72.4%) with reduction percentage of 12.5% and 33.8%. Root length of genotypes decreased by 37.0% in 0.5 MPa and 82.75% in 0.75 MPa, whereas, shoot length reduction was recorded as 38.9% (T1) and 84.6% (T2) as compared to control. This study provided essential information about the performance of advanced wheat genotypes under water stress conditions at early seedling establishment. [ABSTRACT FROM AUTHOR]