Winter jujube orchard nitrogen （N） management aims at increasing N reserves to meet the tree＇s growth requirements. Fertilization strategies should maximize the efficiency of fertilizers, including the choice of th...Winter jujube orchard nitrogen （N） management aims at increasing N reserves to meet the tree＇s growth requirements. Fertilization strategies should maximize the efficiency of fertilizers, including the choice of the optimal timing of N supply. ^15N-urea was applied to winter jujubes on Jinsixiaozao jujubes rootstock to evaluate the effect of application timing on Nstorage and remobilization in mature trees in pot culture. The treatments consisted of ground application before budding （BB）, during fruit core-hardening stage （FCH）, and fruit rapid-swelling stage （FRS）. Nitrogen-use efficiency of treatments were significantly different, which were 2.42% （BB）, 9.77% （FCH）, and 9.01% （FRS） in the dormant and 5.20% （BB）, 16.16% （FCH）, and 10.30% （FRS） in the following full-bloom. N supply in the pre-harvest helped to increase N-reserves of trees and then translocate to the new growth organs the following year. The largest amount of ^15N was detected in the roots and trunks. In all the treatments, the partition rates were highest in coarse roots, which were 30.43% （BB）, 38.61% （FCH）, and 40.62% （FRS）, respectively. ^15N stored in roots and trunks was used by jujube trees to sustain new growth in the following full-bloom. ^15N applied before budding resulted in lower Ndff% in perennial organs （trunks and coarse roots） sampled in the following full-bloom, but fine roots had highest Ndff% （1.28%）. Other organs recovered similar amount of Ndff%. In contrast, FCH and FRS treatments led to higher Ndff% （4.01-5.15%） in the new growth organs （new growth branches, deciduous spurs, leaves and flowers）, but lower Ndff% in perennial branches （1.49-2.89%）. With the delay of ^15N-urea application time, ^15N increased the partitioning to roots. FCH treatment increased N-storage in perennial organ during winter, which should be remobilized to sustain new growth the following spring.展开更多
为了探讨枣与酸枣资源的遗传多样性以及两者的亲缘关系，采用7对 SSR 引物，对16份枣品种（系）和17份酸枣的遗传多样性进行分析。结果表明：16份枣样品共扩增出56个等位基因，有效等位基因数（ Ne）为3.798~10.000，平均为6.953，Shan...为了探讨枣与酸枣资源的遗传多样性以及两者的亲缘关系，采用7对 SSR 引物，对16份枣品种（系）和17份酸枣的遗传多样性进行分析。结果表明：16份枣样品共扩增出56个等位基因，有效等位基因数（ Ne）为3.798~10.000，平均为6.953，Shannon′s信息指数（I）为1.984，期望杂合度（He）为0.837；17份酸枣样品扩增后共检测出73个等位基因，等位基因的有效数目（Ne）为3.273~11.840，平均为7.398，Shannon′s信息指数（I）为2.105，期望杂合度（He）为0.843；枣和酸枣的遗传多样性都很丰富，酸枣的遗传多样性水平高于枣；GenAlEx分析得出，枣和酸枣居群种间遗传分化系数（Fst）为0.055，居群种间基因流（Nm）平均值为4.295，说明居群间基因交流比较频繁。NTSYSpc 聚类分析表明，SSR分子标记可以将枣和酸枣划分为枣类、酸枣类和过渡类3个类群。展开更多
文摘Winter jujube orchard nitrogen （N） management aims at increasing N reserves to meet the tree＇s growth requirements. Fertilization strategies should maximize the efficiency of fertilizers, including the choice of the optimal timing of N supply. ^15N-urea was applied to winter jujubes on Jinsixiaozao jujubes rootstock to evaluate the effect of application timing on Nstorage and remobilization in mature trees in pot culture. The treatments consisted of ground application before budding （BB）, during fruit core-hardening stage （FCH）, and fruit rapid-swelling stage （FRS）. Nitrogen-use efficiency of treatments were significantly different, which were 2.42% （BB）, 9.77% （FCH）, and 9.01% （FRS） in the dormant and 5.20% （BB）, 16.16% （FCH）, and 10.30% （FRS） in the following full-bloom. N supply in the pre-harvest helped to increase N-reserves of trees and then translocate to the new growth organs the following year. The largest amount of ^15N was detected in the roots and trunks. In all the treatments, the partition rates were highest in coarse roots, which were 30.43% （BB）, 38.61% （FCH）, and 40.62% （FRS）, respectively. ^15N stored in roots and trunks was used by jujube trees to sustain new growth in the following full-bloom. ^15N applied before budding resulted in lower Ndff% in perennial organs （trunks and coarse roots） sampled in the following full-bloom, but fine roots had highest Ndff% （1.28%）. Other organs recovered similar amount of Ndff%. In contrast, FCH and FRS treatments led to higher Ndff% （4.01-5.15%） in the new growth organs （new growth branches, deciduous spurs, leaves and flowers）, but lower Ndff% in perennial branches （1.49-2.89%）. With the delay of ^15N-urea application time, ^15N increased the partitioning to roots. FCH treatment increased N-storage in perennial organ during winter, which should be remobilized to sustain new growth the following spring.
文摘为了探讨枣与酸枣资源的遗传多样性以及两者的亲缘关系，采用7对 SSR 引物，对16份枣品种（系）和17份酸枣的遗传多样性进行分析。结果表明：16份枣样品共扩增出56个等位基因，有效等位基因数（ Ne）为3.798~10.000，平均为6.953，Shannon′s信息指数（I）为1.984，期望杂合度（He）为0.837；17份酸枣样品扩增后共检测出73个等位基因，等位基因的有效数目（Ne）为3.273~11.840，平均为7.398，Shannon′s信息指数（I）为2.105，期望杂合度（He）为0.843；枣和酸枣的遗传多样性都很丰富，酸枣的遗传多样性水平高于枣；GenAlEx分析得出，枣和酸枣居群种间遗传分化系数（Fst）为0.055，居群种间基因流（Nm）平均值为4.295，说明居群间基因交流比较频繁。NTSYSpc 聚类分析表明，SSR分子标记可以将枣和酸枣划分为枣类、酸枣类和过渡类3个类群。
