【作者】 汪吉东；

【导师】 刘兆普；

【作者基本信息】 南京农业大学 ， 植物营养学， 2006， 硕士

【摘要】 盐胁迫对植物生长的抑制机理，是个相当复杂的问题。同一植物不同器官和不同发育阶段以及暴于盐渍条件下时间的长短，都可以产生不同的结果。盐分的抑制机理也有差异。关于库拉索芦荟，大田试验已证实其具有耐30％海水能力。且外源氮、磷对其耐盐性的影响研究已有短期温室模拟研究，因此开展30％海水灌溉下库拉索芦荟的氮、磷肥料试验，同时以温室芦荟对外源氮、氯的响应试验为论证，揭示了芦荟对氯的响应及施氮、磷对芦荟生长及某些主要品质指标的影响机理，为库拉索芦荟高产优质栽培及海水灌溉农业发展提供理论支持。主要研究结果如下： 大田30％海水灌溉下芦荟叶片产量效应表现为氮＞磷＞氮磷交互。30％海水灌溉下1年生芦荟叶片的最高产量为26015kg·hm^-2；适宜施N量为141.9kg·hm^-2、施P量（P₂O₅）为84.0kg·hm^-2。在氮肥用量138kg·hm^-2范围内、磷肥施用量84kg·hm^-2范围内，增施氮、磷肥能提高芦荟叶片产量和单叶重，最高增幅分别达109％和52％。同时施氮处理138kg·hm^-2，172.5kg·hm^-2与施磷处理P₂O₅ 84kg·hm^-2组合时单位叶片重、蒽醌含量、芦荟甙含量都较高，其中施氮量在138kg·hm^-2时芦荟甙含量大于施氮172.5kg·hm^-2处理，而蒽醌含量小于后者。因此长期30％海水灌溉下大田适宜的氮、磷肥组合为N2P2处理，处理N3P2次之。 氮磷不同组合下的蒽醌含量均超过单纯施用氮肥的处理。合理增施氮肥能提高库拉索芦荟叶片的蒽醌含量，大田试验施氮量＜242kg·hm^-2时，蒽醌含量随施氮量增加而上升，施氮达242kg·hm^-2时出现下降；温室盆栽试验供氮水平≦10mmol·L^-1时，叶片蒽醌的含量随着施氮量的增加而显著上升，但施氮＞10mmol·L^-1的处理间无显著性差异。 氮肥施用量在N2、N3之间时，增施氮肥对芦荟甙的增产效果明显。继续增施氮肥，芦荟甙加速分解，含量降低。温室施氮试验表明供氮水平≦10mmol·L^-1时，叶片芦荟甙含量随施氮量增加而呈增加趋势，施氮达15mmol·L^-1和17.5mmol·L^-1时芦荟甙加速分解，含量降低；施磷对芦荟甙含量的影响则较为复杂。 施氮促使Na⁺向芦荟老叶的转移，提高幼叶和根系的K⁺／Na⁺比；降低老叶的K⁺／Na⁺比，但RS_K,Na变化趋势不明显，表明增施氮肥是促进芦荟将吸收的盐基离子区隔化来减轻其对幼嫩生长点的毒害作用的，而没有强化有害离子Na⁺、Cl^-选择性吸收能力。因此增施氮肥对长期海水灌溉下芦荟耐盐能力的提高作用有限。更多还原

【Abstract】 The repressive mechanism of salt stress on plant growth is very complicated. The effects vary in different organs of the same plant, different staged plants, different suffering time. There is a considerable discrepancy among the proposed mechanisms. Field experiments have proved the capability of resisting salt stress caused by 30% seawater of aloe. Based on the experimental results obtained, we studied the effects of different application amounts of nitrogen and phosphorus fertilizer on growth, content and distribution of ions in Aloe vera under 30 % seawater irrigation. Both field and pot experiments were carried out to investigate the effects of nitrogen, chloride application amount on growth and quality of Aloe vera. The results showed that:Under 30% seawater irrigation, the maximum leaf yield of one year old Aloe vera of 26015 kg-hm^-2 calculated from the regression equation occurred when the application amounts of nitrogen and phosphorus reached 141.9 kg·hm^-2 and 84.0 kg·hm^-2 , respectively. At the same rate of phosphorus, the single leaf weight of Aloe was increased with the increase of N application, while the greatest single leaf weight was found within the phosphorus supply between 84 to 105 kg·hm^-2 when the same amount of N fertilizer was applied.Within N application of 138 kg·hm^-2 and P₂O₅) application of 84 kg·hm^-2, the leaf yield and single leaf weight were increased by increased amount of N and P application, with the greatest increase of 109 %,52 % respectively. And the combination of N of 138, 172.5 kg·hm^-2 with P of 84 kg·hm^-2 had greater weight of unit leaf, higher content of anthraquinon and aloin. Therefore the best combination was N2P2, and N3P2 take the second place.The co-provision of N and P fertilizer helped to increase the leaf anthraquinon content更多还原