摘要
针对造成我国可控环境条件下蔬菜产量水平低、质量差、效益低、产品药残高和难以全季节生产的关键问题,本研究以番茄为代表蔬菜,从有机土壤基质配比的筛选、基质栽培条件下番茄对主要元素的吸收规律及长季节栽培水肥量化等环节进行研究,以期为基质和专用固态肥工厂化生产提供理论依据。主要研究结果如下:
1、以玉米秸、麦秸、菇渣、锯末等农产废弃物为有机栽培的基质材料,通过与土壤有机肥混合,在物理结构上可以替代草炭、蛭石。由它们按适当比例配制的有机基质栽培均有促进番茄生长,改善植株源库关系,提高产量和改善产品品质的效应,而品质的改善主要表现为番茄的可溶性固形物和番茄红素含量明显提高。大粪干+锯沫(1:3)、大粪干+玉米秸+菇渣(1:2:1)、大粪干+草碳+蛭石(1:1.5:1.5)、大粪干+玉米秸+锯沫(1:2:1)四种配比番茄长势最好、产量、品质最佳;同时四个处理对N、K吸收量大,利用率高。
2、对14种基质配方理化性质的分析表明:当麦秸、玉米秸体积超过总基质体积75%时,因基质蓬松孔隙度比例失调而影响植株的生长,而大粪干超过基质体积的35%时,因离子浓度过大会抑制植株生长造成产量降低。番茄的产量与养分的利用率及果实养分吸收量呈正相关,而与养分总量关系不明显。有机基质栽培条件下,每100kg果实产量的植株养分吸收量范围:N:3.70~10.46g,P_2O_5:0.93~2.30g,K_2O:4.33~12.00g。
3、对长季节番茄栽培进行水肥量化处理。结果表明:灌水量是影响产量的主导因素,高水量处理表现高产的主要原因是因为单果重和单穗果数均明显高出中水量处理。较高的灌水量可获得较大的产量和生物量,但水分生产效率和水分干物质生产率低于中水量处理。相同追肥情况下,灌水量的增加对叶片叶绿素含量和果实品质有稀释效应。从产量、水分利用率和生产成本等方面综合考虑,节水、高产、高效的水肥管理应为:土壤相对含水量为35%左右、肥料组合为尿素+硫酸钾或硫酸铵+硫酸钾,追肥量为140kg/亩,且N:K_2O=1:1.2。
Aiming for the crucial problems of causing the low yield, bad quality, low economic benefits, high residual pesticides and difficult to long-season cultivation, the paper using tomato analyzed and discussed the effects with different organic soil substrates composition, nutrients absorption properties and water-fertilizer coupling in trans-summer high yield cultivation in plastic greenhouse. Primarily study results as follows:
1. The experiment was conducted using soil culture with corn straw, wheat straw, mushroom residue, sawdust and manure as substrates to select the better culture ingredient. The results showed that organic substrate could replace peat and vermiculite in physical structure. The tomato planted in the rational substrates grew finer, the relation between roots and leaves were better, yield and quality of tomato were also improved. The improvement of quality mainly behaved higher soluble solid matte and tomato red element. The formulas of 1hunman excrement and 3 saw dust, 1hunman excrement , 2 corn straw and 1 mushroom residue, Ihunman excrement, 1.5 peat and 1.5 vermiculite were the best favorite substrates among the treatments.
2. The Experiment was analyzed the changes of physical and chemical characters of substrate compositions and nutrients properties of tomato. The results indicated that Formulas with more than 35% manure or 75% crop straw may inhibit plant growth and reduce the yield of tomato. Nutrition use efficiency and fruit nutrition absorption were the major factors on yield. The plant need to absorb N:3.70-10.46g, P2O5 0.93-2.30g, K2O 4.33-12.00g to produce 100kg tomato product.
3. The experiment using tomato in greenhouse studied the different water-fertilizer combination in long season cultivation. The results showed that Irrigation was the major factor on yield. Higher irrigation behaved higher weight of every fruit and the number fruits of every truss. Higher amount irrigation could attain higher yield and dry matter, but water produce efficiency and dry matter productivity was lower than middling amount. With the same fertilizer application, the contents of chlorophy II contents of leaves and quality of tomato were diluted when giving more water. Considering yield , water using efficiency and produce cost, the feasible relative soil water content was 35 %,fertilizer combinations were CO(NH2)2+K2SO4,(NH4)2SO4, the better amount of additional fertilizer was 140kg/ 666.7 m2, nutrients absorbed of N:K2O=1:1.2.
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