Branch growth dynamics, photosynthesis, yield and bean size distribution in response to fruit load manipulation in coffee trees
Branch growth dynamics, photosynthesis, yield and bean size distribution in response to fruit load manipulation in coffee trees
复制标题
咖啡树果实负荷控制下的枝条生长动态、光合作用、产量和豆子大小分布
DOI：
10.1007/s00468-016-1365-x
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
Voswinkel Jan
中科院分区：
文献类型：
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作者：
A. Bote;Voswinkel Jan
关键信息这项研究揭示了机制的动态，导致两年期的咖啡，其后果的碳和氮的竞争，并提出了充分管理的problem. AbstractInequality在果负荷和分支生长的发生两年期豆生产模式的咖啡（咖啡）中起着作用。连续两年在埃塞俄比亚吉马地区进行两次田间试验，研究了水果负荷操作的影响。处理包括将针头阶段的果实负载减少至25、50、75%，并且对照保持每棵树100%的果实（处理编码为T25至T100）。治疗仅在第一年进行。在整个试验期间评价了分支生长和新叶形成、老叶脱落、叶片光合作用的光饱和速率（Amax）、所选分枝上叶片的氮含量以及产量和菜豆特性。结果表明，分支生长和单位叶面积叶片含氮量Na与果实负荷呈负相关，而分枝基生叶损失量随果实负荷和时间的增加而增加，Amax与Na呈强线性相关，随果实负荷的增加而下降。处理当年绿色菜豆产量随载果量的增加而增加，但第二年则相反。在2年的总体上，处理T25和T50产生了处理T75和T100。疏果使豆的大小分布向更大的方向移动。疏果调节了分支生长与果实发育之间的平衡。从而促进了分支生长，提高了豆的大小，并多年稳定产量。
Key messageThe study unraveled the dynamics of mechanisms causing biennality in coffee, its consequences for competition for carbon and nitrogen and suggests means of adequately managing the problem.AbstractImbalance in fruit load and branch growth plays a role in the occurrence of biennial bean production patterns in coffee (Coffea arabicaL.). Effects of fruit load manipulations were studied in two field experiments in the Jimma region, Ethiopia, over two consecutive years. Treatments consisted of reducing fruit loads in the pinhead stage to 25, 50, 75 % and controls keeping 100 % of the fruits per tree (treatments coded T25 through T100). Treatments were applied in the first year only. Branch growth and the formation of new leaves, drop of old leaves, light saturated rate of leaf photosynthesis (Amax), nitrogen content of leaves on selected branches, as well yield and bean characteristics were evaluated throughout the experimental period. The study revealed that branch growth, and leaf N content per unit leaf area,Na, were inversely associated with fruit load, whereas loss of basal leaves on branches increased with fruit load and over time.Amaxwas strongly and linearly associated withNaand declined with increase in fruit load. In the year of treatment green bean yield increased with fruit load, but in the second year the reverse was true. On aggregate over 2 years, treatment T25 and T50 out yielded treatments T75 and T100. Fruit thinning shifted the bean size distribution to larger sizes. In conclusion, fruit thinning modulated the balance between branch growth and fruit development. Thus enhanced branch growth, improved bean size and stabilized yield over years.