Genotypic response of wheat against Stripe rust and Its Geospatial distribution in Southern Punjab

The study was conducted at the Plant Pathology Department, Bahauddin Zakariya University, Multan, during the 2023–2024 crop season. A total of 27 wheat genotypes were tested for stripe rust severity and its correlation with environmental conditions using a Randomized Complete Block Design (RCBD) with three replications. These 27 genotypes were collected from Arid Zone Research Institute (AZRI), Bhakkar. Results showed that six genotypes were resistant to stripe rust. District-level evaluations further identified varieties with varying resistance. Several genotypes exhibited high to moderate resistance, supported by Area Under Disease Progress Curve (AUDPC) values, confirming their potential for cultivation in stripe rust-prone regions. Resistant genotypes such as Akbar-19 and Dilkash-21 displayed strong potential for breeding programs. Moderately resistant varieties like FSD-08 and Sehar-06 provided partial resistance but may require complementary disease management. In contrast, moderately susceptible varieties including Galaxy-13 and Sadiq highlighted the need for strict monitoring and integrated management strategies.

Disease distribution analysis across Southern Punjab revealed distinct spatial patterns. Heatmap results showed Dera Ghazi Khan, Khanewal, and Multan as the most severely affected districts, with multiple hotspots linked to moderately susceptible cultivars and favorable environmental conditions. The choropleth map confirmed Dera Ghazi Khan had the highest mean severity, with several fields recording AUDPC values above 287. Multan and Khanewal also faced high pressure, with many fields showing values between 289–293, categorized as moderately susceptible. Conversely, Vehari and Layyah recorded the lowest severity, with AUDPC values ranging from 33–200, classifying them as resistant to moderately resistant.

Statistical analysis revealed strong associations between disease intensity and environmental factors such as temperature, humidity, and irrigation. Districts with larger proportions of susceptible cultivars like Pak-13 and Akbar-19 showed higher rust incidence, while those planting resistant cultivars such as Dilkash-21 recorded lower severity.