【作者】 俞满源；

【导师】 黄占斌；

【作者基本信息】 西北农林科技大学 ， 生态学， 2003， 硕士

【摘要】 保水剂应用是近年发展迅速的化学节水技术。成本过高，使用技术不完善，作用机制研究的不深入使得保水剂在农业生产中推广缓慢。保水剂与肥料、生长调节剂、微量元素等结合成新产品的应用，具有广阔的的前景。本研究针对目前国内外保水剂发展和研究中存在的问题，就其应用方法及作用机制，在陕北黄土高原地区对北方农田主要作物马铃薯(Solanum tuberosum L.)进行田间试验。苗期保水剂采用两种用法(沟施、穴施)、两个深度(5cm、10～15cm)处理，现蕾期追施氮肥形成保水剂和氮肥(N)交互组合处理。研究了保水剂和N肥对马铃薯生长、产量、水分利用效率(WUE)及N肥利用率的影响，得出以下主要结果： 1．保水剂对土壤团粒结构的形成有促进作用，特别是土壤中0.5-5mm粒径的团粒结构增加显著；保水剂与N肥结合增加了土壤有机质的含量；在有效降水后，保水剂在一定程度上改善、维持了土壤耕层的水分状况；同时保水剂的应用，提高了马铃薯的N肥利用效率。 2．保水剂、N肥都能增加马铃薯根干重，深沟施用保水剂与N肥交互作用明显。穴施保水剂对根／冠影响不大；深沟施用保水剂根／冠有所增加；浅沟施用保水剂，穴施保水剂结合N肥，及单独N肥处理，根／冠降低。 3．保水剂与N肥结合应用改善了马铃薯的生长及光合性能。在苗期，保水剂能有效的促进马铃薯幼苗生长，增加茎粗，增加冠层分枝，增大冠幅面积；保水剂和N肥增加了马铃薯叶面积系数，其中N肥对马铃薯系数的增加贡献大于单用保水剂。保水剂和N肥提高了马铃薯花期及块茎膨大期叶片的光合速率，延长马铃薯植株的光合作用时间14-15d。 4．保水剂结合N肥有效提高盛花期马铃薯的生物量(较对照增加46.7～98.8％)，大幅度增加马铃薯的经济产量75.0-108.3％，特别是大块茎(≥10cm)商品薯的产量增加极明显(160.7-273.8％)。保水剂与N肥提高马铃薯花期WUE(62.3-85.1％)是干物质量增加和耗水减少引起，其中以干物质量增加为主。而整个生育期内WUE的增加(54.6～93.8％)几乎全由干物质量大幅度提高所致，与耗水减少关系甚微。5.从最终产量上反应出保水剂使用方法，沟施优于穴施，深施(10一巧cm)优于浅 施(scm)。表施保水剂，受外界环境，特别是高温影响较大，使保水剂功能受到 抑制。穴施保水剂，由于过于集中，对改变土壤通透性作用不利。开沟深施保水 剂，可最大程度改良马铃薯根系所在部位的土壤结构，增加蓄水能力，降低肥料 的淋溶，满足根系和块茎的发展。更多还原

【Abstract】 Aquasorb applying has become a means of chemical saving water in agriculture in recent years. At present, promotion is restricted since input is high, optimal application methods are unknown and action mechanisms are unclear. Combining Aquasorb and fertilizer, plant growth regulators, microelement or other chemical agent into a new product might has potential development. Based on the existent problems in aquasorb researching, to study optimal application methods and action mechanisms of aquasorb, a field experiment to potato was conducted in Yan’an region in semi-arid Loess Plateau. At seedling stages, aquasorb treatments were applied at two different depths of 5cm and 10-15cm, either put along the furrows or into holes. Nitrogen was used at budding stage. The purpose of the experimet was to study effect of mixed use of Aquasorb and nitrogen fertilizer on growth, yield, water use efficiency (WUE) and nitrogen using efficiency of potato. The major results were as followings:1. Aquasorb applying improved soil texture, increased 0.5-5mm diameter soil granule significantly. Combined with nitrogen fertilizer, which increased organic matter content in soil. After available rainfall, chemical agent improved and maintained good soil moisture. Potato nitrogen fertilizer use efficiency was enhanced for using Aquasorb2.Aquasorb or nitrogen fertilizer increased potato dry root weight. Significant interactions were existed in treatment of deep furrow aquasorb applying with nitrogen. Hole using Aquasorb has no effect on root/shoot(R/S), and deep furrow applying Aquasorb increased R/S. R/S reduced with shallow furrow using aquasorb, hole applying aqusorb with nitrogen, and single using nitrogen.3. Chemical treatment and nitrogen improved growth and Photosynthesis characteristic of potato. Chemical treatment improved plant growth, increased stem diameter, improved plant divarication, and gave rapid increase in canopy area at the seeding stage. Chemical plus nitrogen fertilizer treatment increased leaf index, and it’s increase main for nitrogen. The photosynthetic rate of potato leaves were enhanced both in the flowering stage and the tuber enlarging stage, and potato growth period was prolonged 14-15 days for combined chemical agent and nitrogen fertilizer.4. With mixed chemical and nitrogen fertilizer, potato biomass in flowering stage increased 46.7-98.8%, yield increased by 75-108%, especially for the tubers larger than 10cm. Potato water use efficiency increased dramatically when applying Aquasorb and N fertilizer. At flowering stage, WUE increasing (62.3-85.1%) was related to dry matter production and soil water saving, arid main for the former. To harvest stage of potato, the WUE increasing (54.9-93.8%) main for dry matter accumulated largely but no for saving water increasing.5.The chemical agent was best-incorporated in furrows rather than using holes and a 10-15 cm deep application was better than 5cm depth, which showed from tuber yield. Shallow application of chemical agent influenced by environment seriously, especially for high temperature, which limited functions of chemical agent. Application in hole weren’t benefit improving soil texture. The capacity of absorbing and making water available in the soil-root system, reducing fertilizer loss were enhanced through Application in deep furrow, which avail to development of root and tuber.更多还原