Shavrukov Yuri, Kurishbayev Akhylbek, Jatayev Satyvaldy, Shvidchenko Vladimir, Zotova Lyudmila, Koekemoer Francois, de Groot Stephan, Soole Kathleen, Langridge Peter
School of Biological Sciences, Flinders University, Bedford Park, SA, Australia.
School of Agriculture, Food and Wine, University of Adelaide, Urrbrae, SA, Australia.
Front Plant Sci. 2017 Nov 17;8:1950. doi: 10.3389/fpls.2017.01950. eCollection 2017.
Drought escape (DE) is a classical adaptive mechanism which involves rapid plant development to enable the completion of the full life-cycle prior to a coming drought event. This strategy is widely used in populations of native plants, and is also applicable to cereal crops such as wheat. Early flowering time and a shorter vegetative phase can be very important for wheat production in conditions of terminal drought since this can minimize exposure to dehydration during the sensitive flowering and post-anthesis grain filling periods. A gradual shift toward early flowering has been observed over the last century of wheat breeding in countries with a Mediterranean-type climate and frequent terminal drought. This trend is predicted to continue for wheat production in the coming years in response to global climate warming. The advantage of early flowering wheat is apparent under conditions of impending terminal drought, and modern varieties are significantly more productive due to minimization of the risk associated with drought stress. Under favorable conditions, a short vegetative phase can result in reduced plant biomass due to the reduction in time available for photosynthetic production and seed nutrient accumulation. However, high yield potential has been reported for the development of both shallow and deep roots, representing plasticity in response to drought in combination with the early flowering trait. Wheat productivity can be high both in well-watered and drought-affected field trials, where an efficient strategy of DE was associated with quick growth, yield potential and water use efficiency. Therefore, early flowering provides a promising strategy for the production of advanced drought-adapted wheat cultivars.
干旱逃避（DE）是一种经典的适应机制，它涉及植物的快速发育，以便在即将到来的干旱事件之前完成整个生命周期。这种策略在本地植物种群中广泛应用，也适用于小麦等谷类作物。在终末期干旱条件下，早开花时间和较短的营养生长期对小麦生产非常重要，因为这可以在敏感的开花期和花后灌浆期将脱水暴露降至最低。在具有地中海型气候且频繁发生终末期干旱的国家，在过去一个世纪的小麦育种过程中，已观察到逐渐向早开花转变的趋势。预计未来几年，由于全球气候变暖，小麦生产仍将延续这一趋势。在即将发生终末期干旱的条件下，早开花小麦的优势显而易见，由于与干旱胁迫相关的风险降至最低，现代品种的产量显著提高。在有利条件下，较短的营养生长期可能会因光合生产和种子养分积累的可用时间减少而导致植物生物量降低。然而，据报道，浅根和深根的发育都具有较高的产量潜力，这体现了结合早开花性状对干旱的可塑性响应。在水分充足和受干旱影响的田间试验中，小麦都能实现高产，其中有效的干旱逃避策略与快速生长、产量潜力和水分利用效率相关。因此，早开花为培育适应干旱的先进小麦品种提供了一种有前景的策略。
