Monitoring of rust virulence pattern through avirulence/virulence formula

Abstract

The idea of this study was to be vigilant with rust virulence pattern changes in the region and to organise wheat breeding and variety release programmes in the light of findings of rust virulence patterns. The survey was carried out during March–April (2010 and 2011) on the rust trap nurseries planted at different Agra-ecological condition in Pakistan. The rust trap nursery consisted of 40 Lr differentials and 24 Yr differentials and data were recorded following modified Cobb’s scale. The studies revealed that there were no virulence for Lr9, Lr19, Lr23+, Lr25, Lr28, Lr27+31 Lr32, Lr34, Lr36 and Lr37 and Yr3, Yr5, YR8, Yr10, Yr15, Yr18, and Yrsp observed during this period. Among the varieties Iqbal-2000, Uqab-2000, Lasani-2008, Faisalabad-2008, AARI-2011, Millat-2011 and Pb-2011 exhibited resistance path for LR and YR. Moderate YR was observed on Shafaq-2006 & Chenab-2000 ranging from 20–30 M RMS. In these studies the susceptible check variety Morocco was almost 80–100S for LR and YR.

Keywords:

• Puccinia striiformis
• Puccinia triticina
• virulence
• resistance genes
• monitoring

Acknowledgements

Thanks to Dr Makhdoom Hussain (Director, Wheat Research Institute, Faisalabad), Mr Altaf Hussain Tariq (Director, RARI, Bahawalpur), Ch Umar (Director, Punjab Seed Corporation, Khanewal), Dr Mujahid Hussain (Wheat Coordinator, NARC, Islamabad), Dr Muhammad Saleem (Director, CCRI, Pirsabak) and Dr Tilla Muhammad Khan (Director, NIFA, Peshawar) for their cooperation in providing facilities and land for planting trap nurseries at their institutes and Muhammad Mohsin Raza (Department of Plant Pathology, the University of Agriculture, Faisalabad) for reviewing the paper and helpful comments.