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71.
雍菜对受灭多威污染养殖水体的净化及对鱼类生长的影响   总被引:1,自引:0,他引:1  
灭多威属高毒农药,其可经地表淋溶等途径污染养殖水体。为了研究雍菜对水体中灭多威及其他水质指标的净化效能以及对罗非鱼生长的影响,以灭多威、罗非鱼、雍菜和室内养殖系统为试材,根据《水和废水监测分析方法》中的方法测得水质指标数据,以液相色谱-质谱联用仪(LC-MS)测得水体中灭多威浓度,以试剂盒测定谷胱甘肽(GSH)含量(DTNB法)、超氧化物歧化酶(SOD)活性(WST-1法)、过氧化氢酶(CAT)活性(紫外法)。研究结果表明,罗非鱼的生长速度随着水体中灭多威浓度的上升而降低。受灭多威污染可致罗非鱼肝脏氧化压力增大,SOD、CAT和GSH的活性发生变化。雍菜可通过机体吸收有效降低养殖水体中灭多威的含量,对受灭多威污染水体中TN、NH4 +-N、NO3 --N、NO2 --N等具一定的净化作用,并可减轻罗非鱼肝脏的氧化应激。研究显示,水体种植雍菜可有效减轻灭多威对水体的污染,保证鱼类的生长。  相似文献   
72.
UV-B增强对菠菜生长发育和生理特性的影响   总被引:3,自引:2,他引:3  
采用大田栽培试验方法在自然光条件下,研究了模拟紫外辐射UV—B增强对菠菜生长发育的影响。分析结果表明,随着UV—B辐射的增加,菠菜的干重、叶面积、绿叶数、株高生长均呈降低趋势,而且UV—B越强,降低程度越大;UV—B辐射增加,菠菜叶片类黄酮含量增加,叶绿素含量降低,蒸腾速率减小,光合作用减弱。  相似文献   
73.
通过正交实验 ,分析沼气发酵残余物 (沼液、沼渣 )作为肥料 ,其施肥量、配施品种、施用方式等因素对油菜和菠菜硝酸盐积累的影响。影响菠菜硝酸盐积累的显著因素按作用程度大小依次为硫酸铵、沼渣和喷施沼液。油菜的显著因素依次为硫酸铵、沼渣和灌施沼液。并根据维持较高产量水平的基础上硝酸盐含量较低的原则 ,确定了优选的施肥方案。结果表明 ,采用沼渣作底肥 ,配合沼液追肥 ,生产的蔬菜满足高产和优质的双重目的 ,既利用了农业废物 ,避免沼气池的二次污染 ,又节约化肥 ,降低生产成本 ,具有一举数得的优点  相似文献   
74.
以菠菜和油菜为供试材料,采用盆栽试验的方法,研究菠菜和油菜对微量元素铜的吸收规律及其体内铜的不同化学结合形态的差异。结果表明:在铜处理浓度不超过160mg/kg土时,随铜处理浓度的增加,菠菜对铜的吸收呈先升后降的趋势.而油菜对铜的吸收却随铜处理浓度的升高而一直保持增加的趋势。在菠菜和油菜的不同生长时期,均以中期对铜的吸收量大于收获期的吸收量。铜在菠菜和油菜体内的化学结合形态,菠菜是以活性较高的水溶态为主,油菜则以活性较低的残余态为主。  相似文献   
75.
化学药剂处理对蕹菜种子发芽的影响   总被引:1,自引:1,他引:1       下载免费PDF全文
采用培养皿发芽法,研究了化学药剂处理对蕹菜种子发芽的影响。结果表明,GA3 Ca2 混合液处理蕹菜种子,对促进种子发芽和提高种子活力表现加成作用,以50 g/L GA3 5mmol/L Ca2 处理较为适宜。蕹菜种子经稀盐酸预处理1 h后,以100 mg/L GA3浸种处理,可明显提高种子发芽势和活力指数,促进种子发芽。用30~50 mmol/L的低浓度NaCl胁迫处理蕹菜种子,能提高种子发芽率,但随着NaCl胁迫浓度的增大,对发芽抑制作用明显增强。低浓度(0.05%~0.07%)ZnSO4浸种可促进种子发芽,高浓度(>0.09%)则抑制种子发芽。  相似文献   
76.
土壤施用脲酶抑制剂醌氢醌后蕹菜体内氮代谢的变化研究   总被引:1,自引:0,他引:1  
盆栽试验研究施用醌氢醌后蕹菜体内N代谢的变化结果表明,醌氢醌使蕹菜叶片硝酸还原酶、谷氨酸脱氢酶和谷酰胺合成酶活性、总N及蛋白质含量提高,游离氨基酸含量降低。盆栽蕹菜醌氢醌适宜用量为2 0~4 0mg/kg土  相似文献   
77.
Most previous researches have focused on biochar application in agricultural soils; however, limited information is available concerning the effects of biochar amendment on greenhouse substrate properties. A greenhouse experiment was conducted to investigate effects of wheat straw biochar(0–160 m L L-1) and super absorbent polymer(SAP, 0.8 g L-1) on physical and chemical properties of a substrate based on spent pig litter compost and the growth of water spinach(Ipomoea aquatica Forsk). Total porosity, water-holding capacity, p H and electrical conductivity(EC) of the substrate significantly increased with increasing biochar rates, especially in the substrate without SAP. The values of p H and EC were significantly lower in the substrate with SAP than those without SAP at the high biochar application rates(100–160 m L L-1). The germination rates of water spinach decreased with increasing biochar rates when biochar was added alone(76.9%–83.7%), whereas the rates increased to 83.6%–85.8% when biochar was added in combination with SAP. Growth parameters of water spinach and nutrient uptake by shoots and roots increased with increasing biochar rates and reached the maximum values at the biochar rate of 100 m L L-1. There were significant cubic relationships between the uptake of nutrients(N, P, and K) and biochar rates, both with and without SAP addition. In order to avoid negative effects on plant growth,the biochar application rate should be controlled at an optimal level(100 m L L-1). The SAP addition not only enhanced the positive effects of biochar application on the properties of the substrate, but also inhibited the excessive rise of p H and EC following biochar additions, which led to better plant growth and enhanced nutrient uptakes by water spinach.  相似文献   
78.
Abstract

Phytoremediation is a natural approach to use plants for decontaminating soil. A pot-culture factorial experiment in completely randomized design was conducted to evaluate the effects of four levels [0, 25, 50, and 100?mg/kg] of chromium (Cr) with three levels [0, 0.5, and 1-M solution) of plant defense inducer salicylic acid (SA) on growth, physiological processes, and biochemical responses of Malabar spinach (Basella alba). Results showed that Cr significantly decreased vine length (VL), leaf number (LN), leaf area (LA), fresh- (FBM), and dry-biomass (DBM), root length (RL), and dry-matter ratio (DMR). Cr also significantly decreased SPAD (chlorophyll contents), by 9% to 29% and net photosynthesis (Pn) rates, by 36% to 71%, but increased transpiration (E) rates, by 1.5 to 2.7 times and stomatal conductance (C), by 1.7 to 3.5 times, as compared with the control. Proline contents increased with an associated decrease in oxidative enzyme activities such as peroxidase, (POD) and catalase, (CAT) with increasing Cr levels. Cr significantly reduced the Dry Matter Ratio (DMR) (12% to 42%) and LA (10% to 35%), RL -stress (11% to 27%), and SPAD (10% to 28%) stress tolerance indices. The integrated stress tolerance index (ISTIndex) of Malabar spinach was reduced (by 6% to 23%) by Cr stress, as compared to the control. SA application, in contrast, partially alleviated the severity of Cr toxicity effects on VL, LN, LA, FBM, DBM, RL, and DMR and increased the SPAD (by 12%), Photosynthesis Net (Pn) (by 53% to 68%), and stomatal conductance (C) (by 35% to 50%), respectively. Furthermore, SA increased plant stress tolerance indices by increasing antioxidant enzymatic functions. SA application recovered the ISTIndex at all Cr levels, and the recovery effect on plants was more pronounced by 0.5-M SA than by other SA treatments. The mechanism of stress tolerance as induced by SA application may help plants to better survive and maintain growth in presence of higher Cr contents in soil. Results suggested that SA, as a plant defense inducer, can be exploited for improving Cr phytoremediation potential of Malabar spinach to decontaminate soil.  相似文献   
79.
pp. 859–864
Behavior of nitrogen in the media was investigated when the aqueous phase produced by methane fermentation was supplied as liquid fertilizer.
When the aqueous phase was supplied to masa-soil,      included in masa-soil was nitrified to      . Additionally, in masa-soil,       absorption was observed. On the other hand, in the case of coconut fiber and rockwool,     has been hardly nitrified. From above results, it was determined that       toxic effect from the aqueous phase on tomato plants growth was inhibited by means of the progress of nitrification and       absorption by masa-soil.
  However, nitrification was restrained so that       was fixed in masa-soil. On the other hand, in the sampled field soil,       was not fixed, and was nitrified immediately. In the field soil, there was a great deal of generated      . In comparison with masa-soil.  相似文献   
80.
外源钙对盐胁迫下菠菜生理特性的影响   总被引:2,自引:0,他引:2  
刘丽  曾长立 《湖北农业科学》2015,54(1):118-121,125
设计不同浓度的Ca Cl2溶液,在对菠菜(Spinacia oleracea L.)盐胁迫前采用根部浇灌和叶部喷施的方法进行诱导,钙诱导5 d后,对菠菜幼苗再进行150 mmol/L NaCl溶液处理,测定其形态建成和生理生化指标。结果表明,外源钙能显著提高盐胁迫下菠菜的形态建成指标;显著增加可溶性蛋白质和叶绿素含量;显著提高SOD和POD活性;显著降低丙二醛(MDA)和游离脯氨酸含量。当外源钙离子浓度为30mmol/L时,其降低盐胁迫伤害效应的效果较好。  相似文献   
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