Developing systems to control male fertility in wheat for hybrid breeding, enhanced pollen production and increased yield.

控制肥力和成功繁殖是谷类作物结实和作物产量的关键。自花授粉作物的产量能力往往低于通过优良品系杂交产生的杂交种。这种“杂交优势”不仅能增加产量，还能抵抗非生物和生物胁迫。因此，杂交作物提供了以可持续的方式提高产量和生产率的机会。然而，杂交生产面临的挑战是需要避免许多作物在异交前自交的自然趋势，同时确保杂交制种的有效异花授粉。以可逆方式控制肥力的机制对提供这种系统至关重要，这是小麦育种的一个关键目标，因为杂交小麦可能实现重大增产。杂交种子的生产也依赖于有效的雄性来给雌性品系授粉，因此，最佳的花粉产生、活力和释放的性状也是重要的。小麦花粉发育对环境伤害特别敏感，开花后活力迅速下降，发育过程中对非生物胁迫(如高温和低温)普遍敏感。由于环境压力导致的肥力下降通常出现在小麦作物中，这可能对产量产生重大影响。因此，对不同环境条件和非生物胁迫的生殖恢复能力对可持续产量至关重要。这只能通过详细了解花粉发育和调节生育能力的系统来实现。因此，对谷物繁殖的深入了解是发展小麦杂交育种系统的关键。这项建议将通过提供对谷物中花粉发育的更多了解来解决这些问题，以开发控制小麦育性的可切换系统，但也将通过确定提高花粉产量和活力的性状来解决这些问题，特别是在环境胁迫下，这对确保育种计划中的授粉成功至关重要。通过研究这些性状背后的机制和产生育种和选择的工具，将实现提高作物生产力和抗逆性的有效育种。该项目将利用我们在理解谷物花粉发育方面的进展来开发控制谷物肥力的系统，重点是小麦。此外，还将筛选导入系和育种群体，以确定最佳受精的性状，包括高产量、高释放和耐久性。这些研究将围绕环境的影响，特别是温度和日长对花粉育性的影响展开。我们将确定这些性状在优秀商业种质中的益处和稳定性，使它们的潜力得以确定。我们还将评估这些生育基因座的自然变异，并开发标记，使这些可能影响生育能力的特征，特别是在不同环境条件下的潜在影响，在繁殖种群中得到遵循。

Control of fertility and successful reproduction is key to grain set and thus crop yield in cereals. Self-pollinating crops tend to have lower yield capability than hybrids generated by intercrossing between elite lines. This "Hybrid Vigour" has been shown to increase yield, but also abiotic and biotic stress resistance. Hybrid crops thus provide opportunities to increase yield and productivity in a sustainable manner. However, the challenge for hybrid production is the need to avoid the natural tendency for many crops to self-fertilise prior to outcrossing, whilst ensuring effective cross-pollination for hybrid seed production. Mechanisms that control fertility in a reversible manner are critical to deliver such systems and this is a key goal for wheat breeding, since major yield enhancements are possible from hybrid wheat. Hybrid seed production also relies upon effective males to pollinate the female lines, therefore traits for optimal pollen production, viability and release are also of major importance. Wheat pollen development is particularly sensitive to environmental damage, with rapid reductions in viability post anthesis, combined with general sensitivity to abiotic stress (e.g. high and low temperature) during development. Reductions in fertility due to environmental stress are often seen in wheat crops and these can have major impacts on yield. Reproductive resilience to variable environmental conditions and abiotic stress is therefore critical to sustainable yields. This can only be delivered by detailed knowledge of pollen development and systems to regulate fertility. Deep understanding of cereal reproduction is therefore key to the development of wheat hybrid breeding systems.This proposal will address these issues by providing greater understanding of pollen development in cereals towards developing switchable systems for the control of wheat fertility, but also by identifying traits for enhanced pollen production and viability, particularly under environmental stress, which are critical for ensuring successful pollination in breeding programmes. By investigating the mechanisms behind these traits and by generating tools for breeding and selection, effective breeding to increase crop productivity and resilience will be realised.The project will use our progress in understanding cereal pollen development to develop systems for controlling cereal fertility, focussing on wheat. In addition introgression lines and breeding populations will be screened to identify traits for optimal fertilisation, including high pollen production, release and durability. These will be focused around the impact of environment, particularly temperature and day length, on pollen fertility. We will determine the benefit and stability of these traits in elite commercial germplasm, enabling their potential to be determined. We will also assess natural variation at these fertility loci and develop markers to enable these traits, which could potentially impact on fertility particularly under different environmental conditions, to be followed in breeding populations.