【作者】 崔敏；

【导师】 张志国；

【作者基本信息】 山东农业大学 ， 土壤学， 2008， 硕士

【摘要】 无土栽培目前已成为设施农业的重要内容,也是农业作物工厂化生产的重要形式,是发展高效农业的新途径。作为无土栽培的基础,栽培基质是决定植物根系生长环境的最主要因素之一,目前常用的基质中某些成分如泥炭、树皮等许多有机物质,由于其表面蜡质等疏水性基团的存在而造成其具有斥水性(Water repellency);由于斥水性的存在,会造成基质难以湿润,从而导致植物生长不匀,影响种苗质量,同时也造成灌溉水随基质的大孔隙和容器壁流失,造成水分的浪费。因此,解决基质的湿润性问题尤为重要。常使用添加强亲水型表面活性剂或湿润剂(Wetting agent,wetter)的方法来降低水分子的表面张力,从而改善基质的亲水性和持水性能。本试验针对草炭的斥水性,选用常用湿润剂分析纯壬基酚聚氧乙烯醚(OP-10)、工业用OP-10和分析纯聚山梨醇酯80(SP)作为添加剂,研究了湿润剂对草炭湿润性能、基本理化性质的影响以及湿润剂对以草炭为主要栽培基质的育苗和盆栽作物生长状况的影响,旨在选定合适的湿润剂种类和确定其最适用量,并评价湿润剂对作物生长的影响,以期为湿润剂在基质中的推广提供参考。试验主要从以下方面进行:(1)研究了湿润剂对草炭湿润与再湿润能力的影响,结果表明三种湿润剂均能显著减少草炭的湿润与再湿润时间,其中分析纯OP-10的湿润时间最短,湿润效果最好,其次是工业用OP-10,分析纯聚山梨醇酯80(SP)的效果最差。综合考虑效果与成本,认为价廉的工业用OP-10的应用前景最好。工业用OP-10能够显著提高草炭的渗透速率和一次性吸水量,其中2%浓度即可达到最佳效果。(2)研究了工业用OP-10对草炭孔隙特性、水分特性等基本理化性质的影响。结果表明,适量的湿润剂(浓度小于1%)可以提高草炭的持水能力,随着湿润剂浓度的增加持水能力逐渐下降,通气逐渐增强。湿润剂在1%的浓度水平下,能够使草炭在保持更多的水分的同时有更大的通气性;同时,湿润剂能显著提升基质的毛管水上升高度和减少水分的散失时间,这表明湿润剂能够提高草炭的毛管水含量和保水能力;湿润剂对草炭的容重、pH值影响较小。(3)研究了湿润剂对矢车菊、高羊茅的发芽状况的影响,发芽率试验结果表明0.5%浓度的湿润剂溶液就能引起两种作物发芽率的显著降低,说明过高的湿润剂用量会对作物产生毒害,抑制作物的生长。以草炭为栽培基质的育苗试验结果表明:适量的湿润剂能增加作物的发芽率和促进植物的生长发育。湿润剂在1.5%-6%的浓度水平对高羊茅苗期生长没有不良影响,且在3%的浓度水平效果最好;而湿润剂在0.5%的浓度水平就可使矢车菊达到最好的生长状况。(4)研究了湿润剂对盆栽松果菊生长发育的影响以及松果菊生长期间基质湿润性能和速效养分的变化,结果表明:湿润剂在作物栽培的85天内均能显著提高基质的湿润时间和渗透率,但其效力已经随着反复的淋溶有所减弱,应在移栽后第35天进行补充。湿润剂能使加速基质中的速效氮、速效钾等养分的淋溶,因此应该减少每次的浇水量以减少养分的淋溶。适量的湿润剂(浓度小于3%)能够增加松果菊的株高、冠幅、根长、地上部、地下部鲜重和G值(壮苗指数),在0.75%的浓度水平下使松果菊的生长状态最好,当浓度高于3%就会对作物产生毒害,抑制作物的生长发育。(5)研究了不同灌水量下湿润剂对松果菊生长发育的影响,结果表明:全量灌水(200ml)的条件下湿润剂对作物的生长发育影响不大,但在170ml和140ml的低量灌溉条件下湿润剂能够显著改善作物的生长状况,1.5%的浓度水平下达到最好。这充分证明了湿润剂的节水作用,1.5%的湿润剂加入量能够使作物在产量增加的基础上节水30%,为湿润剂的推广应用提供了理论数据。更多还原

【Abstract】 Soilless cultivation has now become an important part of protected agriculture, it is also an important form of manufacturing agricultural crops and a new way to develop high-efficiency agriculture. As the basis for soilless cultivation, horticultural substrate is the most important environmental factors which deciding the plant root growth。Some components in the current fine horticultural substrate such as peat, tree bark and other organic materials, because of the existence of waxy surface caused they have water repellency. Since the existence of water repellency, it is very difficult to make these surbstrate wet when watered them, and it will cause water waste. If water can not infiltrate the substrates rapidly and make it wet , it will cause germination rate and quality of plant decreace. Therefore, settle the water repellent problem is particularly important.This experiment was conducted to study the effects of applying three different wetting agents on the wetting & rewetting ability and basic physical & chemical properties of water- repellent substrate-peat, and estimat the germination & growth instances of some plants growed in peat medium that was added wetting agent. After application of three wetting agents- Fenxi Chun - Analytical Nonylphenol polyoxyethylene ethers (OP-10), industrial OP-10 and Fenxi Chun- Analytical Polysorbate 80 (SP), the main test conducted on the following:(1)Studied the influences of three wetters which commonly used on wetting and rewetting time、penetration rate of peat. The results showed that all the three wetting agents improved wetness of peat, of which OP-10 got best results, and SP worked most weakly. Taking into account the costs, industrial OP-10 have a brighter prospect, which not only increased the infiltration rate but also enhanced irrigation efficiency, and concentration 2% received best results comparing with other treatments.(2) Studied the influences of industrial OP-10 on pore property and moisture property and other basic physical and chemical properties of peat. The results showed that adding fit amount of wetting agent in peat can increase the water-holding properties, but with increasing concentration of wetting agent water-holding capacity decreased gradually, ventilation enhanced gradually. Wetting agent at 1% concentration level can keep the peat keep more water, that will be very beneficial to the growth of crops.Wetting agent can significantly improve the height of capillary water and reduce water lost time, this showed that wetting agent can increase water content of capillary water and the water-holding ability of peat. The influences of industrial OP-10 on the density, pH of peat were little.(3) Studied the influences of industrial OP-10 on the state of germination of Cornflower and Festuca arundinacea. Test results showed that the germination rate of the two plant had a significant reduction on 0.5 percent concentration of the wetter solution, we can conclude that exorbitant use of the wetter will produce poison to crops and inhibit the growth of crops. The germination and seedling growth test showed that: the fit amount of wetting agent can increase crop germination rate and promot the growth of plant. Wetting agent at 1.5%-6% of the concentration levels had not adversely affected of Festuca arundinacea’s growth, and at 3 percent of the concentration level has the best effect; but the wetting agent in the concentration level of 0.5 percent would enable the Cornflower have the best growth conditions.4) Studied the influences of industrial OP-10 on wetting ability and nutrients quick-impact changes of peat during the growth period of Echinacea and on the growth instance of Echinacea planted in pot, results showed that wetting agent in crop cultivation for 85 days can significantly improve the wetting time and penetration rate of substrate. This showed the effects of wetting agent was still valid in 85 days after transplanting, but its effectiveness has been weakened by repeated leaching, it should be supplemented in the first 35 days after transplanting to achieve the best wetting effect. Wetting agent can make the content of available nitrogen, potassium nutrients in substrate reduced slightly, this may because wetting agent can make these nutrients dissolved in water more easily, under normal irrigation mode, more nutrients would be eluviated along with the water. So we shoud reduce the volume of each time irrigation to reduce the nutrients leaching. Suitable amount of wetting agent (concentration of less than 3 percent) can increase the height, crown breadth, root length, shoot dry weight, root dry weight and G values (seedling index) of Echinacea purpurea, in the concentration level of 0.75 percent had the best growth state, when the concentration level was more than 3%, it would poison and inhibit the growth of the Echinacea purpurea.5) Studied the influences of wetting agent under different irrigation volumes on the growth status of Echinacea purpurea, the results show that under whole volume irrigation conditions, wetting agent have little effect on the growth and development of the Echinacea purpurea, but under 170 ml and 140 ml of low irrigation volumes conditions, wetting agent can significantly improve the growth of the plant, and at the concentration level of 1.5 percent, wetting agent have the best effect. This had proved that wetting agent can save water distinctly. The amount of wetting agent at the concentration level of 1.5 percent can save 30 percent water, at the same time increase plant growth. This report provided a basis theoretical data to extend use of wetting agent.更多还原