AICRP on Maize, University of Agricultural Sciences, Dharwad, Karnataka, India.
Department of Genetics and Plant Breeding, College of Agriculture, University of Agricultural Sciences, Dharwad, Karnataka, India.
PLoS One. 2023 Mar 27;18(3):e0283528. doi: 10.1371/journal.pone.0283528. eCollection 2023.
Corn is one of the most important cereal crops in the world with highest yield potential. Nevertheless, its potential productivity is constrained by the occurrences of drought stress worldwide. Besides, in the era of climate change, frequent occurrences of severe droughts are predicted. The present investigation was carried out at Main Agricultural Research Station, University of Agricultural Sciences, Dharwad in split plot design to study response of twenty-eight new corn inbreds under drought free (well-watered) conditions and drought simulated by withholding irrigation from 40 to 75 DAS to create water stress. Significant differences among the corn inbreds, moisture treatments and interaction between inbreds were observed for morpho-physiological, yield and yield components indicating differential response of corn inbreds. The inbreds CAL 1426-2 (higher RWC, SLW& wax and lower ASI), PDM 4641(higher SLW, proline, & wax, and lower ASI) and GPM 114 (higher proline & wax, and lower ASI) were drought tolerant. These inbreds are having higher production potential (>5.0 t/ha) under moisture stress condition with less per cent reduction (<24.4%) over non-moisture stress condition and hence are putative candidates for developing drought tolerant hybrids suitable for rainfed ecosystem besides using them in population improvement program to combine different drought tolerant mechanisms to evolve highly potent drought tolerant inbreds. The results of the study suggested that proline content, wax content, anthesis silking interval, relative water content can be better surrogate traits to identify drought tolerant inbreds in corn.
玉米是世界上最重要的谷类作物之一，具有最高的产量潜力。然而，其潜在生产力受到全球干旱胁迫的限制。此外，在气候变化的时代，预计会频繁发生严重的干旱。本研究在达瓦尔农业大学主要农业研究站以裂区设计进行，以研究 28 个新的玉米自交系在无干旱（充分灌溉）条件下和通过从 40 到 75 天龄开始停水模拟干旱条件下的响应，以创造水分胁迫。在形态生理、产量和产量构成因素方面，玉米自交系、水分处理和自交系之间的互作都存在显著差异，表明玉米自交系的反应存在差异。自交系 CAL 1426-2（更高的 RWC、SLW 和蜡质以及更低的 ASI）、PDM 4641（更高的 SLW、脯氨酸和蜡质以及更低的 ASI）和 GPM 114（更高的脯氨酸和蜡质以及更低的 ASI）具有耐旱性。这些自交系在水分胁迫条件下具有较高的生产力潜力（>5.0 吨/公顷），与非水分胁迫条件相比，减少的百分比（<24.4%）较小，因此除了在群体改良计划中使用它们来结合不同的耐旱机制以培育出高抗旱能力的自交系外，它们也是适合雨养生态系统的耐旱杂交种的潜在候选者。研究结果表明，脯氨酸含量、蜡质含量、开花吐丝间隔、相对水含量可以更好地作为鉴定玉米耐旱自交系的替代性状。
