Achieving yield gains in wheat

Abstract

Wheat provides 20% of calories and protein consumed by humans. Recent genetic gains are <1% per annum (p.a.), insufficient to meet future demand. The Wheat Yield Consortium brings expertise in photosynthesis, crop adaptation and genetics to a common breeding platform. Theory suggest radiation use efficiency (RUE) of wheat could be increased~50%; strategies include modifying specificity, catalytic rate and regulation of Rubisco, up-regulating Calvin cycle enzymes, introducing chloroplast CO2 concentrating mechanisms, optimizing light and N distribution of canopies while minimizing photoinhibition, and increasing spike photosynthesis. Maximum yield expression will also require dynamic optimization of source: sink so that dry matter partitioning to reproductive structures is not at the cost of the roots, stems and leaves needed to maintain physiological and structural integrity. Crop development should favour spike fertility to maximize harvest index so phenology must be tailored to different photoperiods, and sensitivity to unpredictable weather must be modulated to reduce conservative responses that reduce harvest index. Strategic crossing of complementary physiological traits will be augmented with wide crossing, while genome-wide selection and high throughput phenotyping and genotyping will increase efficiency of progeny screening. To ensure investment in breeding achieves agronomic impact, sustainable crop management must also be promoted through crop improvement networks.

Strategic crossing of biomass and harvest index—source and sink—achieves genetic gains in wheat

“…Balancing biomass (source) with yield components (sink) through breeding While a number of studies have suggested that yield and radiation use efficiency can be increased by improving source and sink balance (Slafer and Savin 1994;Reynolds et al 2012), this is the first time the hypothesis has been tested in a realistic breeding context. Results indicate that selecting parents with high expression of biomass (source) and crossing to sources with good expression of sink traits (HI, KNO, TKW etc.)…”

“…Nonetheless, BM and HI are necessarily a function of genetically simpler traits which can be considered in greater detail when making more complex strategic crosses ( Fig. 1; Reynolds et al 2012). …”

Effect of Rust Disease on Photosynthetic Rate of Wheat Plant

“…(1) Giymatly 2/17: relatively early headed and moderately resisistant to diseases; (2) Experiment was carried out with two variantscontrol and 25% Tilt treatment. Each genotype was grown with three replications.…”

“…The growth of productivity of major crops in recent years has decreased significantly [1]. Especially is apparent for wheat, the most important crop in the food security of the most regions of Eurasia, America and Australia [2]. In 2013, world production of wheat was 713 million tons, making it the third most-produced cereal after maize (1,016 million tons) and rice (745 million tons) [3].…”

Differential response of wild and cultivated wheats to water deficits during grain development: changes in soluble carbohydrates and invertases

“…Wheat is the most important food crop of the world in terms of harvested area, trade value and human nutrition, having more influence on global food security than any other crop (Reynolds et al 2012). With current productivity increasing at a rate of about 1.1% per annum (Dixon et al 2009), or even stagnating in some regions (Brisson et al 2010), meeting the needs of a growing population with rising per capita consumption is a serious challenge.…”