Morphological and physiological responses of two coffee progenies to soil water availability
Morphological and physiological responses of two coffee progenies to soil water availability
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DOI：
10.1016/j.jplph.2006.12.004
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发表时间：
2007-12-01
影响因子：
4.3
通讯作者：
DaMatta, Fabio M.
中科院分区：
文献类型：
--
作者：
Dias, Paulo C.;Araujo, Wagner L.;DaMatta, Fabio M.
干旱是影响咖啡生长和生产的主要环境限制。比较了供水对代表耐旱（Siriema）和干旱敏感（Catucai）基因型的两个咖啡后代的生长、生物量分配、水关系和气体交换的影响。它们在 12 升盆中生长，直到 4 个月大，然后接受两次为期 60 天的浇水处理：植物接受 100% 的蒸腾水（对照植物）或对照植物（干旱胁迫植物）蒸腾水量的一小部分（约 40%）。在控制条件下，Siriema 的生长速度比 Catucai 快。无论浇水方式和后代如何，相对生长率（RGR）与净同化率（NAR）和长期水分利用效率（WUE）均呈正相关，但与生物量分配的差异无关。两个后代都通过以下方式应对干旱胁迫：(i) RGR 和 NAR 均类似下降，但分配发生微小变化（如果有的话）； (ii) 叶水势下降，这种情况在卡图卡伊比在西里马发生的程度更大，尽管它们表现出相似的渗透压和弹性调节能力； (iii) 主要由于非气孔因素造成的净光合作用的类似减少； (iv) 蒸腾速率降低，同时长期 WUE 增加。然而，在干旱条件下，Siriema 相对于 Catucai 对照条件下的较低蒸腾速率和较高的长期 WUE 仍然存在。总体而言，这些后代之间的主要差异很大程度上与植物用水的差异有关，这可能与 Siriema 水分状况的改善有关。讨论了选择咖啡基因型对高 WUE 的可能影响。 (C) 2007 爱思唯尔有限公司。版权所有。
Drought is a major environmental constraint affecting growth and production of coffee. The effects of water supply on growth, biomass allocation, water relations, and gas exchange in two coffee progenies representing drought-tolerant (Siriema) and drought-sensitive (Catucai) genotypes were compared. They were grown in 12-L pots until 4-months old, when they were submitted to two watering treatments for 60d: plants receiving either 100% transpired water (control plants) or a fraction (about 40%) of the amount of water transpired by control plants (drought-stressed plants). Under control conditions, Siriema grew faster than Catucai. Regardless of the watering regimes and progenies, relative growth rate (RGR) was positively correlated both with net assimilation rate (NAR) and tong-term water-use efficiency (WUE), but not with differences in biomass allocation. Both progenies responded to drought stress through (i) similar decreases in both RGR and NAR with marginal, if any, changes in allocation; (ii) decreases in leaf water potential, which occurred to a greater extent in Catucai than in Siriema, even though they have showed similar abilities to adjust osmotically and elastically; (iii) similar reductions in net photosynthesis due mainly to nonstomatal factors; and (iv) decreases in transpiration rate coupled with increased long-term WUE. However, the Lower transpiration rate and the higher tong-term WUE as found in Siriema relative to Catucai under control conditions persisted under drought conditions. Overall, the major differences between these progenies were largely associated with differences in plant water use, which was likely related to the improved water status of Siriema. The possible implications of selecting coffee genotypes for high WUE are discussed. (C) 2007 Elsevier GmbH. All rights reserved.