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71.
蔬菜无土栽培基质初步筛选研究 总被引:6,自引:0,他引:6
以草炭、蛭石、炉渣、废菇料和粉碎后的玉米秸秆为原料,按不同材料种类及比例混合制成8种蔬菜无土栽培复合基质,测定并比较了8种复合基质的理化性质,初步筛选出适宜蔬菜栽培的优良基质。结果表明:8种基质的容重、pH值和总孔隙度均在蔬菜栽培的适宜范围内;大小孔隙比、基质电导率及成本上各有优劣。通过综合考量,初步优选出的无土栽培基质为基质Ⅳ(V棉籽皮∶V炉渣=1∶1)、基质Ⅵ(V棉籽皮∶V蛭石=1∶1)和基质Ⅶ(V玉米秸秆∶V棉籽皮∶V蛭石=1∶1∶2)。 相似文献
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Closed cycle soilless techniques can be adopted to minimize water and fertilizer losses in greenhouse cultivation. There is a general lack of information regarding the soilless cultivation of vegetables with closed cycle subirrigation techniques, specifically when using saline water. In this study, a trough bench subirrigation system (SUB), with two fertilizer concentrations (“100%”, containing 9.8 mol m−3 N-NO3, 1.6 mol m−3 P-H2PO4, 8.7 mol m−3 K+, 2.8 mol m−3 Ca+, 1.8 mol m−3 Mg+, 4 mol m−3 S-SO4, and “70%”, containing 70% of the macronutrient concentration) in the nutrient solution (NS), was compared with open cycle drip-irrigation (DRIP with “100%” NS). For all the three treatments, NS was prepared using rain water (0.05 dS m−1) and adding NaCl (1 g L−1), in order to simulate moderate saline irrigation water. The effect of the treatments on tomato (Solanum lycopersicum L.) plant growth, yield, fruit quality, water use efficiency (WUE) and fertilizer consumption was evaluated. Substrate and recirculating NS composition were also studied. Subirrigation, regardless of NS concentration, reduced plant height (by 30 cm), leaf area (by 1411 cm2), total fresh and dry weight (by 429 and 48.5 g plant−1, respectively) but not dry matter percentage of the whole plant, with respect to DRIP. Yield was reduced when plants were subirrigated with the higher concentrated NS, but no differences with open cycle DRIP were recorded when the lower NS concentration was used in SUB. Fruit quality was not affected by irrigation system or NS concentration. The higher WUE was obtained with subirrigation. NaCl accumulated similarly over the crop cycle in recirculating NS of both SUB treatments and in growing substrates of all the three treatments. Higher salt concentration was found in subirrigated substrates, in particular in the upper part of the substrate profile. Fertilizers accumulated in the subirrigated substrates when the higher NS concentration was used, but not when the NS concentration was reduced by 30%. The results of this study indicate that tomato can be grown successfully in a closed cycle subirrigation system, using saline water, by reducing the fertilizer NS concentration normally used with traditional open cycle systems. 相似文献
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通过设置5种基质和5个遮阴梯度,对结缕草(Zoysia japonica)扦插苗进行交叉处理,经3个月的冷季生长后,测定幼苗的存活率、生长特性、构件性状及生物量等指标,分析基质和遮阴对冷季生长结缕草幼苗构件性状及生物量分配的影响。结果表明:基质对结缕草存活率、干重、鲜重及生物量分配均有极显著影响,利于结缕草冷季存活与生长的基质顺序为成熟紫色土 > 建渣土 > 粗砂土 > 石谷子土 > 腐殖土;遮阴度对结缕草存活率有极显著影响,30%左右遮阴利于结缕草在冷季存活与生长;基质和遮阴度互作对结缕草幼苗构件性状及生物量分配有显著影响,基质是影响主要因子,遮阴度次之;基质和遮阴协同作用对结缕草构件生物量分配影响为叶 > 根 > 茎,结缕草可依据基质和遮阴采取相应的形态塑性和生长策略,以提高适应性和抗寒性。 相似文献
77.
小麦和玉米苗期是磷素营养的关键期和敏感期,研究两种作物苗期对介质供磷反应,可为合理施用磷肥提供参考.试验设缺磷对照、低磷胁迫、中等磷胁迫和正常供磷(P2O5含量分别为0、0.05 mmol·L-1、0.3 mmol·L-1和0.5 mmol·L-1) 4种磷水平,选取小麦"小偃22号"、"兰考4号"和玉米"屯玉65号"、"户单4号"为指标作物,用营养液培养法研究小麦、玉米苗期磷累积量对介质不同供磷水平的反应差异.结果表明,不同介质供磷水平下,两种作物苗期磷累积量显著不同且因作物类型、基因型、器官及测定时期不同而异.总体而言,介质供磷后,苗期早期生长阶段(出苗后25 d以前),小麦的介质最佳供磷水平较玉米高;苗期后期(出苗后40~50 d),小麦和玉米最佳供磷水平一致.如果以低磷胁迫作为对比进行分析,玉米苗期整株磷累积量对介质供磷的敏感性比小麦强;从不同基因型来看:"兰考4号"对介质供磷的敏感性强于"小偃22号","屯玉65号"和"户单4号"基本一致.缺磷条件下小麦较玉米磷效率高,供磷条件下玉米较小麦高;但不同基因型间规律性较差. 相似文献
78.
玉米秸秆复配基质对茄子幼苗生长和光合
参数的影响 总被引:1,自引:0,他引:1
以沈茄1 号茄子为试材,传统的草炭蛭石混合基质作对照,将玉米秸秆基质与不同粒径沸石
按不同比例混配形成玉米秸秆复配基质,研究其理化性质及在茄子育苗中的应用效果。结果表明,玉米
秸秆基质添加沸石可增加复配基质的持水孔隙度,降低复配基质的pH 值和电导率(EC),沸石添加量为
20%~40% 时,复配基质理化性状达到育苗要求,且茄子幼苗出苗率、长势、质量优于对照,其中玉米秸
秆基质添加30%(10 目)沸石时茄子幼苗的长势最好,总叶绿素含量、净光合速率最高,且壮苗指数显
著高于对照及其他处理。 相似文献
79.
为了解大棚基质栽培的大蒜在单、套作条件下生长及产量的差异,设置番茄单作、番茄/大蒜
套作、大蒜单作3 个处理,测定大蒜生长量、产量及基质理化性质。结果表明:与番茄套作的大蒜形态指
标显著低于单作大蒜;套作显著降低了大蒜的鳞茎质量和总产量,同时显著提高了独头率和独头蒜产量。
番茄/大蒜套作土地当量比高达1.56,具有明显的套作优势。在及时摘除番茄老叶、精细管理的栽培措施下,
套作大蒜独头率高达58.1%。大蒜单、套作基质的氮、磷、钾含量均较高,蔗糖酶和脲酶活性、细菌和放
线菌数量也无显著差异,套作大蒜生长的限制条件是光照。 相似文献
80.
Donovan P. German Michael N. Weintraub Christian L. Lauber Steven D. Allison 《Soil biology & biochemistry》2011,43(7):1387-1397
Microbial digestive enzymes in soil and litter have been studied for over a half century, yet the understanding of microbial enzymes as drivers of ecosystem processes remains hindered by methodological differences among researchers and laboratories. Modern techniques enable the comparison of enzyme activities from different sites and experiments, but most researchers do not optimize enzyme assay methods for their study sites, and thus may not properly assay potential enzyme activity. In this review, we characterize important procedural details of enzyme assays, and define the steps necessary to properly assay potential enzyme activities in environmental samples. We make the following recommendations to investigators measuring soil enzyme activities: 1) run enzyme assays at the environmental pH and temperature; 2) run proper standards, and if using fluorescent substrates with NaOH addition, use a standard time of 1 min between the addition of NaOH and reading in a fluorometer; 3) run enzyme assays under saturating substrate concentrations to ensure Vmax is being measured; 4) confirm that product is produced linearly over the duration of the assay; 5) examine whether mixing during the reaction is necessary to properly measure enzyme activity; 6) find the balance between dilution of soil homogenate and assay variation; and 7) ensure that enzyme activity values are properly calculated. These steps should help develop a unified understanding of enzyme activities in ecosystem ecology. 相似文献