Journal Article
Strategic crossing of biomass and harvest index—source and sink—achieves genetic gains in wheat
Matthew P. Reynolds; Alistair J. D. Pask; William J. E. Hoppitt; Kai Sonder; Sivakumar Sukumaran; Gemma Molero; Carolina Saint Pierre; Thomas Payne; Ravi P. Singh; Hans J. Braun; Fernanda G. Gonzalez; Ignacio I. Terrile; Naresh C. D. Barma; Abdul Hakim; Zhonghu He; Zheru Fan; Dario Novoselovic; Maher Maghraby; Khaled I. M. Gad; ElHusseiny G. Galal; Adel Hagras; Mohamed M. Mohamed; Abdul Fatah A. Morad; Uttam Kumar; Gyanendra P. Singh; Rudra Naik; Ishwar K. Kalappanavar; Suma Biradar; Sakuru V. Sai Prasad; Ravish Chatrath; Indu Sharma; Kishor Panchabhai; Virinder S. Sohu; Gurvinder S. Mavi; Vinod K. Mishra; Arun Balasubramaniam; Mohammad R. Jalal-Kamali; Manoochehr Khodarahmi; Manoochehr Dastfal; Seyed M. Tabib-Ghaffari; Jabbar Jafarby; Ahmad R. Nikzad; Hossein Akbari Moghaddam; Hassan Ghojogh; Asghar Mehraban; Ernesto Solís-Moya; Miguel A. Camacho-Casas; Pedro Figueroa-López; Javier Ireta-Moreno; Jorge I. Alvarado-Padilla; Alberto Borbón-Gracia; Araceli Torres; Yei Nayeli Quiche; Shesh R. Upadhyay; Deepak Pandey; Muhammad Imtiaz; Monsif U. Rehman; Manzoor Hussain; Makhdoom Hussain; Riaz Ud-Din; Maqsood Qamar; Muhammad Sohail; Muhammad Y. Mujahid; Gulzar Ahmad; Abdul J. Khan; Mahboob A. Sial; Pompiliu Mustatea; Eben von Well; Moses Ncala; Stephan de Groot; Abdelraheem H. A. Hussein; Izzat S. A. Tahir; Amani A. M. Idris; Hala M. M. Elamein; Yann Manes; Arun K. Joshi
Euphytica · Vol. 213, Issue 11 · 2017
Abstract
To accelerate genetic gains in breeding, physiological trait (PT) characterization of candidate parents can help make more strategic crosses, increasing the probability of accumulating favorable alleles compared to crossing relatively uncharacterized lines. In this study, crosses were designed to complement “source” with “sink” traits, where at least one parent was selected for favorable expression of biomass and/or radiation use efficiency—source—and the other for sink-related traits like harvest-index, kernel weight and grains per spike. Female parents were selected from among genetic resources—including landraces and products of wide-crossing (i.e. synthetic wheat)—that had been evaluated in Mexico at high yield potential or under heat stress, while elite lines were used as males. Progeny of crosses were advanced to the F 4 generation within Mexico, and F 4 -derived F 5 and F 6 generations were yield tested to populate four international nurseries, targeted to high yield environments (2nd and 3rd WYCYT) for yield potential, and heat stressed environments (2nd and 4th SATYN) for climate resilience, respectively. Each nursery was grown as multi-location yield trials. Genetic gains were achieved in both temperate and hot environments, with most new PT-derived lines expressing superior yield and biomass compared to local checks at almost all international sites. Furthermore, the tendency across all four nurseries indicated either the superiority of the best new PT lines compared with the CIMMYT elite checks, or the superiority of all new PT lines as a group compared with all checks, and in some cases, both. Results support—in a realistic breeding context—the hypothesis that yield and radiation use efficiency can be increased by improving source:sink balance, and validate the feasibility of incorporating exotic germplasm into mainstream breeding efforts to accelerate genetic gains for yield potential and climate resilience.