Boussora Faiza, Allam Mohamed, Guasmi Ferdaous, Ferchichi Ali, Rutten Twan, Hansson Mats, Youssef Helmy M, Börner Andreas
Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstraße 3, 06466, Gatersleben, Germany.
Institute of Arid Lands of Medenine, Route du Djorf Km 22.5, Médénine, Tunisia.
Bot Stud. 2019 Jul 10;60(1):13. doi: 10.1186/s40529-019-0261-2.
Salinity is a significant environmental stress factor limiting crops productivity. Barley (Hordeum vulgare L.) has a natural tolerance to salinity stress, making it an interesting study object in stress biology research. In the present study, for the first time the effect of salinity stress on barley inflorescence developmental stages was investigated. Five spring barley genotypes irrigated with saline water (12.5 ds/m NaCl) were compared to controls treated with normal tap water. We measured abscisic acid (ABA) concentrations in the apical, central and basal sections of the immature inflorescence at green anther (GA) stage. The role of ABA in spikelet primordia development, atrophy and abortion and final yield was evaluated.
A time course experiment starting from double ridge until green anther (GA) stages revealed that salinity reduced the length of spike developmental stages in all genotypes causing shortened of the plant life cycle. The shortened plant life cycle negatively affected plant height and number of tillers/plant. Salinity also affected spikelet primordia development. In both control and salinity treated plants apical spikelet abortion started in late awn primordium (AP) stage. However, under salinity treatment, significantly more spikelets were aborted, thus directly affecting plant yield potential. ABA, which plays a role in the spikelet/floret abortion process, was markedly elevated in the base and apex of salt treated spikes correlating with an increased spikelet abortion in these regions.
Overall, salinity treatment reduced all plant and yield-related parameters investigated and turned some of the correlations among them from positive to negative or vice versa. Investigations of ABA role in floral development and phase duration of barley spike showed that, ABA regulates the spikelet/floret abortion process affecting the yield potential under salinity and control conditions.
盐度是限制作物生产力的一个重要环境胁迫因素。大麦（Hordeum vulgare L.）对盐胁迫具有天然耐受性，使其成为胁迫生物学研究中一个有趣的研究对象。在本研究中，首次研究了盐胁迫对大麦花序发育阶段的影响。将5个用盐水（12.5 ds/m NaCl）灌溉的春大麦基因型与用普通自来水处理的对照进行比较。我们测量了未成熟花序在绿花药（GA）阶段顶端、中部和基部的脱落酸（ABA）浓度。评估了ABA在小穗原基发育、萎缩和败育以及最终产量中的作用。
从双棱期到绿花药（GA）阶段的时间进程实验表明，盐度缩短了所有基因型的穗发育阶段长度，导致植物生命周期缩短。缩短的植物生命周期对株高和单株分蘖数产生负面影响。盐度还影响小穗原基发育。在对照和盐处理植株中，顶端小穗败育均始于芒原基（AP）后期。然而，在盐处理下，更多的小穗败育，从而直接影响植物的产量潜力。在小穗/小花败育过程中起作用的ABA在盐处理穗的基部和顶端显著升高，与这些区域小穗败育增加相关。
总体而言，盐处理降低了所有研究的植物和产量相关参数，并使其中一些参数之间的相关性从正变负或反之亦然。对ABA在大麦穗花发育和阶段持续时间中的作用的研究表明，ABA调节小穗/小花败育过程，在盐度和对照条件下影响产量潜力。
