不同树龄骏枣树养分吸收差异研究

【目的】旨在明确不同树龄骏枣树形成单位产量所需的各器官营养元素年吸收量的异同点,以期为骏枣生产中的科学均衡施肥提供理论依据。【方法】以新疆阿克苏地区4、 7和10年生骏枣树作为试材,从枣树地上部分各器官分别采样,测定N、 P、 K、 Ca、 Mg、 Mn、 Fe、 Zn和Cu含量。【结果】骏枣树形成地上部各器官单位生物量所需要的养分含量,不同树龄间相比差异均不显著,但其生物量在总生物量中所占的百分率有差异,4、 7、 10年生骏枣树果实占地上部年总生物量的百分率依次为72.9%、 73.7%、 75.7%,叶片依次为5.4%、 5.2%、 5.1%,花依次为1.3%、 1.5%、 1.4%,茎枝依次为20.4%、 19.5%、 17.6%,三个树龄骏枣树各器官生物量的大少顺序均为果实＞茎枝＞叶片＞花。每形成1000 kg果实的总生物量随着树龄的增大而逐渐减少,茎枝保留和剪掉部分生物量均降低。采前落果率随树龄增加上升,叶片生物量减少,受精花生物量上升,而其掉落部分生物量表现先上升后下降。三个树龄骏枣地上部分生物量年增加量所需要的各营养元素量顺序均为K＞N＞Ca＞Mg＞P＞Fe＞Zn＞Mn＞Cu,每形成1000 kg果实所需要吸收的养分量非常接近,4年生骏枣树为N 22.8 kg、 P 1.7 kg、 K 34.0 kg、 Ca 7.4 kg、 Mg 5.0 kg、 Mn 54.5 g、 Fe 916.9 g、 Zn 202.8 g、 Cu 42.5 g; 7年生骏枣树为N 22.7 kg、 P 1.7 kg、 K 33.9 kg、 Ca 7.3 kg、 Mg 4.9 kg、 Mn 53.9 g、 Fe 907.2 g、 Zn 204.5 g、 Cu 42.0 g; 10年生骏枣树N 22.1 kg、 P 1.7 kg、 K 33.4 kg、 Ca 6.8 kg、 Mg 4.7 kg、 Mn 51.8 g、 Fe 871.3 g、 Zn 204.8 g、 Cu 40.4 g。【结论】3种树龄骏枣树地上部年总生物量中果实生物量与其余生物量的比例约为3∶1,且形成1000 kg果实所需的养分量也基本一致。由于总生物量和果实产量随树龄的增加而增加,因此,对养分的总需求量增加。但是由于果实生物量所占比例有所增加,测算单位产量所需要的各营养元素年吸收量时,也应考虑果实以外器官的年生物量所需要的养分吸收量,才能得到较准确的肥料施入量和各营养元素的比例。

Nutrient uptake differences of Jun jujube in different ages

【Objectives】 The objective of this study was to clarify the differences of Jun jujube in annual nutrient demands for the production of unit fruit yield in different tree ages.【Methods】Samples of the 4, 7 and 10-year’s old Jun jujube trees in Aksu Area were tested for the N, P, K, Ca, Mg, Mn, Fe, Zn and Cu contents in aboveground organs, and a proposal was put forwarded in the practical fertilization of the Jun jujube.【Results】There are no significant differences in the nutrient contents in the same organs of Jun jujube trees of different ages, but there are some differences in the percentages of the aboveground organs’ biomass to their total biomass. For the 4, 7 and 10 years’ old jujube trees, the percentages of the fruits in the total biomass are 72.9%, 73.7% and 75.7%, those of leaves are 5.4%, 5.2% and 5.1%, those of flowers are 1.3%, 1.5% and 1.4%, and those of stems are 19.5%, 20.4% and 17.8%, respectively. The biomass with all the 3 ages are in order of fruits stems leaves flowers. As the age increasing, the total biomass required for the production of 1000 kg fruits are increased gradually, the preharvest dropping ratios of fruit are increased, the leaf biomass are decreased, the retained flower biomass shows an upward trends, the dropping flower biomass is first increased and then decreased, and the biomass of pruned and retained stems and branches are also reduced. The orders of nutrient element contents required for growth of the aboveground organs in the three ages of Jun jujube trees are K N Ca Mg P Fe Zn Mn Cu. The nutrient amounts for 1000 kg fruit production in 4 year’s old Jun jujube are N 22.8 kg, P 1.7 kg, K 34.0 kg, Ca 7.5 kg, Mg 5.0 kg, Mn 54.5 g, Fe 916.9 g, Zn 202.8 g, Cu 42.5 g; in 7 year’s old trees are N 22.7 kg, P 1.7 kg, K 33.9 kg, Ca 7.3 kg, Mg 4.9 kg, Mn 53.9 g, Fe 907.2 g, Zn 204.5 g, Cu 42.0 g; and in 10year’s tree are N 22.1 kg, P 1.7 kg, K 33.4 kg, Ca 6.8 kg, Mg 4.7 kg, Mn 51.8 g, Fe 871.3 g, Zn 204.8 g, Cu 40.4 g. 【Conclusions】The ratios of fruit biomass to other aboveground organs’ total biomass in all the three tested ages of Jun jujube trees are about 3∶1. The nutrient uptakes for the 1000 kg of fruit production are almost the same. As the total biomass and fruit yield are increased with the age of trees, which leads to higher nutrient requirement. As the increase of the percentage of fruit in total biomass, the total nutrient requirement should be considered including the other organs’ nutrients uptake.