Abstract

Plant diseases are among the major causes of crop yield loss and food insecurity. In South Africa, stem rust caused by Puccinia graminis Pers. f. sp. tritici. Eriks. & E. Henn. (Pgt) is an important disease of wheat. Records of stem rust occurrence in South Africa date back to the late 1720’s, when it was first discovered in the south-western wheat growing areas of the Western Cape. Although growing stem rust resistant cultivars is one of the most economic and environmentally feasible strategies, one of the challenges in host-plant resistance is that Pgt frequently acquires new virulence to overcome resistance genes in existing cultivars. There is strong evidence that the pathogen continues to evolve through mutation and genetic recombination. The appearance of stem rust race Ug99 (TTKSK, North American race notation) in East Africa in 1999 and subsequent epidemics in Kenya and Ethiopia was accompanied by the occurrence of four Ug99 variants (TTKSF, TTKSP, PTKST and TTKSF+) in South Africa. These have resulted in a renewed interest in understanding the status of Pgt races and stem rust resistance in the world as well as the need for a new host-plant resistance strategy. The current review summarises up-to-date literature on the prevalence of stem rust races in South Africa, and also draws attention to the resistance genes and strategies currently deployed to combat this disease. The aim of the review was to provide perspectives on research milestones and guide future research programs for reducing losses incurred by stem rust of wheat in South Africa. Key words: Durable resistance; Pathogen variability; Puccinia graminis f. sp. tritici.

Highlights

  • Whea at stem m rust in Soutth Africa: Cu urrent s status s and earch d directio ons futurre rese

  • As a result of renewed interest on host resistance, different research groups in South Africa comprised of farmers, plant pathologists, geneticists and breeders together with international collaborators are exploring ways to combat stem rust disease by searching for new sources of durable resistance

  • Norman Borlaug, the Nobel laureate, who is widely considered as the father of wheat improvement in the

Read more

Summary

Introduction

Whea at stem m rust in Soutth Africa: Cu urrent s status s and earch d directio ons futurre rese. Council-Small Grain Institute (ARC-SGI) in Bethlehem, South Africa, initiated annual rust surveys which coincided with the mandatory inclusion of stem rust resistance genes in all newly released cultivars (Pretorius et al, 2007). The Sr24 stem rust resistance gene was effective against most races of Pgt and was used in commercial wheat cultivars worldwide (Jin et al, 2008), detection of the races 2SA100 and

Results
Conclusion
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call