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1.
海南岛马哇幼龄椰树氮,磷,钾,镁肥用量试验   总被引:1,自引:0,他引:1  
马哇幼龄椰树,施用磷肥,促进生长。每年每公顷增值1634.7-2284.7元,增产最显著,施用氮肥增加椰果产量,每年每公顷增值1513.4-1881.5元,促进生长,提高椰果的椰干率和椰干含油量,施用镁肥增加椰果产量,每年每公顷增值602.7-1098.7元;施用钾肥,提高椰果产量,每年每公顷增值225.8-865.5元。  相似文献   

2.
硫酸钾镁肥对小白菜、茶叶、西瓜产量和品质的影响   总被引:1,自引:0,他引:1  
通过田间试验,研究在施用氮、磷肥基础上,配施硫酸钾镁肥对小白菜、茶叶、西瓜的产量、品质及主要农艺性状的影响。结果表明:施用钾肥都能增加产量,提高品质。施硫酸钾镁与施硫酸钾或氯化钾相比,小白菜产量提高3.81%和9.88%,茶叶产量提高8.75%和3.81%;小白菜NO3-含量降低180.7 mg/kg和52.5 mg/kg;茶叶游离氨基酸含量增加0.30%和0.27%,茶多酚含量减少0.90%和3.63%,咖啡碱含量增加0.31%和0.19%;西瓜中心可溶性固形物增加0.07%和0.57%,Vc含量提高8.84%和7.35%。施用硫酸钾镁比施用硫酸钾或氯化钾每公顷增加经济效益733~4041元。  相似文献   

3.
通过氮磷钾不同配比施用对几种种植制度的作物产量、经济效益以及土壤肥力状况的比较 ,结果表明 :几种耕作方式 :春大豆 -秋芝麻 -油菜、春大豆 -秋绿豆 -油菜、甜瓜 -秋大豆-油菜 ,比当地习惯种植春大豆∥红薯 -油菜 ,分别增加纯收入 89.9%、2 8.8%、12 .7% ;定位施用氮磷钾肥 ,5个处理对全年作物的产量效益变化是 NPK>NP>P>N>CK,一年施用一季NPK肥 ,即每公顷 N12 0∶ P6 0∶K90就可以获得最佳的丰产效益 ,三季作物总产较不施肥增加 2 2 .5 %~ 2 5 .0 % ,且经济效益每公顷增加纯收入 9349.5~ 10 75 8元 ;定位施用 NPK肥 ,能提高土壤有机质含量 1.9%~ 19.0 % ,同时能满足每季作物所需 N的含量 ,不同施肥处理 ,其土壤有效养分变化各不相同。  相似文献   

4.
植物刺激素寡糖具有提高作物抗逆作用、促进作物生长的功效。在黄瓜生长早期及生长期施用复合寡糖制剂,通过分析复合寡糖对植株光合作用特性、产量和黄瓜3个生长阶段植株叶片、根系及根围土微生物群落,阐明复合寡糖施用对黄瓜的增产增效作用。采用大棚小区试验,设置清水对照、化学常规和复合寡糖3个处理,于盛花期、盛果期和拉秧期分别采集黄瓜叶片、根系和根围土样本,测定各个采样时期黄瓜产量、叶绿素含量和抗氧化酶活性,进行高通量测序检测样本细菌群落结构和组成。复合寡糖的施用与清水对照相比,提高了单株黄瓜产量,使得每公顷的产量增加了4.96%;显著提高了黄瓜叶片叶绿素的含量,复合寡糖处理对比其他处理能够显著提升叶片叶绿素含量的相对值(SPAD)6.14%~11.46%;同时提高了叶片的超氧化物歧化酶活性39.9%~81.5%,提高了过氧化氢酶活性8.4%~40.4%,提高了过氧化物酶活性1.19%~18.5%。高通量测序分析结果表明,复合寡糖的施用提高了叶片微生物群落中鞘氨醇单胞菌属(Sphingomonas sp.)和甲基杆菌属(Methylobacterium sp.)的丰度,它们均具有促进植物生长和协助植...  相似文献   

5.
硫酸钾镁肥对小白菜、茶叶、西瓜产量和品质的影响   总被引:19,自引:0,他引:19  
通过田间试验,研究在施川氮、磷肥基础上,配施硫酸钟镁肥对小白菜、茶叶、西瓜的产量、品质及主要农艺性状的影响。结果表明:施用钟肥都能增加产垦,提高品质。施硫酸钾镁与施硫酸钾或氯化钾相比,小白菜产量提高3.81%和9.88%,茶叶产量提高8.75%和3.81%;小白菜NO3^-含量降低180.7mg/kg和52.5mg/kg;茶叶游离氨基酸含量增加0.30%和0.27%,茶多酚含量减少0.90%和3.63%,咖啡碱含量增加0.31%和0.19%;西瓜中心可溶性固形物增加0.07%和0.57%,Vc含量提高8.84%和7.35%。施用硫酸钾镁比施用硫酸钾或氯化钾每公顷增加经济效益733~4041元。  相似文献   

6.
通过田间试验,研究了施用硼、锌和钼肥对紫云英种子产量、根瘤菌数量的影响。结果表明:与不施硼、锌和钼肥处理相比,施用硼、锌和钼肥处理的紫云英种子产量提高13.7%~38.9%,且差异均显著(P<0.05);主要因单株结荚数和每荚种子粒数等产量构成因素提高,施用硼、锌和钼肥处理的单株结荚数和每荚种子粒数分别提高18.9%~44.3%和21.4%~33.3%,均达显著差异(P<0.05)。施用硼、锌和钼肥可以促进紫云英根瘤的形成,施用硼、锌和钼肥处理紫云英根瘤数增加2.1%~82.4%。施用钼肥处理紫云英的种子产量、经济性状和根瘤数量均高于未施钼肥处理。说明紫云英生长发育及种子产量形成对钼的敏感性高于其它微肥种类。  相似文献   

7.
刘枫  刘英  何传龙  王道中 《土壤通报》2007,38(6):1246-1248
淮北砂姜黑土大豆施硒试验结果表明:每公顷施用亚硒酸钠2kg以下,不会导致大豆减产。每公顷施硒4kg以下,不会出现大豆硒中毒症状。每公顷施硒2kg籽粒产量最高。大豆地上部硒浓度与积累量随硒施用量增加而提高,但籽粒硒吸收量明显大于茎叶。随着施硒量的增加,试验土壤的硒含量也相应提高。  相似文献   

8.
徐聪  吴迪  王磊  李传哲  杨苏  孙丽  汪吉东  张永春  艾玉春 《土壤》2021,53(3):491-498
通过对两个小麦生长季进行田间监测,探究了施用菌渣对黄河故道区低产田土壤理化性质、小麦根系生长和产量的影响。试验共设7个处理,分别为不施用菌渣(CK),施用低量(6 t/hm~2;S1)、中量(12 t/hm~2;S2)和高量秸秆质菌渣(18 t/hm~2;S3),施用低量(6 t/hm~2;B1)、中量(12 t/hm~2;B2)和高量木质菌渣(18 t/hm~2;B3)。结果表明:相比CK,施用菌渣后第1年和第2年的小麦产量分别增加了32.4%~51.8%和38.8%~101.2%(P0.05);逐步回归结果显示,每施用1t/hm~2的菌渣,可提升小麦产量0.21t/hm~2(P0.01);不同菌渣类型间的小麦产量和经济效益无显著差异(P0.05),秸秆质菌渣18 t/hm~2处理下可获得最高产量和经济效益;施用菌渣2年后,0~10 cm土壤有机质显著提升24.7%~57.7%(P0.05),且0~10 cm土壤容重和紧实度分别降低了11.6%~18.2%和20.8%~35.7%(P0.05;B1处理除外);根系形态指标与小麦产量间均呈正相关关系,菌渣施用对小麦苗期根系总根长、总表面积、总体积和分叉数的增加有显著促进作用(P0.05);小麦产量与土壤有机质含量呈正相关关系,与0~10 cm土壤容重和紧实度呈显著负相关关系(P0.05),说明菌渣施用后土壤有机质水平提升、物理结构改善是产量增加的关键机制。本研究表明,针对土壤有机质水平低、物理结构较差的黄河故道区低产田,施用菌渣是改善该地区土壤物理特性,促进作物根系生长,快速提升产量,增加经济效益的有效手段。  相似文献   

9.
磷肥残效及农业系统养分循环再利用中长期试验   总被引:7,自引:1,他引:7  
在辽宁西部褐土上进行的一12年中长期田间试验结果表明:每年施用小剂量磷(P14.4kghm-2)和每6年1次大剂量磷(P86.4kghm-2)两种施磷方式的作物增产效果相似而以前者略优,两种施磷方式的磷肥利用率12年平均分别为0.38和0.36,表明磷肥在该土壤上有着极持久的残效。在施用氮磷肥基础上,每年以80%的收获籽实和2/3的秸杆喂猪、垫圈,猪圈肥循环回田,11年平均每公顷可增产粮食1吨,增产率17%。经连续施用12年循环回田猪圈肥后土壤的供氮力显著提高,年供氮量180~200kg(N),玉米产量每公顷接近9吨,当季施用氮肥几无增产作用。  相似文献   

10.
试验得出,播量与施氮量不同处理组合的产量以每公顷播量105kg施纯氮225kg的小麦产量6724.95kg/hm2最高。施氮量因播量不同酌情增减,每公顷播种52.5、105及157.5kg的最大施氮量分别为270~285、210~225及195~210kg/hm2,施用氮肥对提高小麦子粒品质的作用明显,播量与小麦品质无关。  相似文献   

11.
Appropriate compost standards are being considered in Canada. Five aspects of compost safety and quality are being evaluated; probably the most controversial aspect is the standards for metals in compost. In order to assist in the development of appropriate standards, the authors began an extensive research project in October, 1993 to determine the bioavailability of metals from compost and compost-metal mixtures. Swiss chard was grown in compost-amended soils or compost in a growth room using five treatments of increasing percentages of compost in the media (0, 25 percent, 50 percent, 75 percent, 100 percent compost (v/v)). A Truro loamy sand and a race-track manure-biosolids compost (RTM-biosolids) supplemented with a high metal biosolids were used in a completely randomized design with five replicates. Dry matter yield, metal content in plant tissue, and total metal uptake were evaluated as well as the total and DTPA-extractable metal content in the compost-soil mixes. The results of this and five other experiments conducted by the authors will help determine whether the suggested limits for As, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, Se and Zn in composts are appropriate.  相似文献   

12.
Abstract

The phytotoxicity of five nonessential elements (Co, V, Ti, Ag, Cr) to higher plants was studied in solution culture experiments with bush beans (Phaseolus vulgaris L. C.V. Improved Tendergreen). All, but in varying degrees, tended to concentrate in roots with a decreasing gradient to stems and leaves. Cobalt was one of the more mobile of the five trace metals. Its toxicity was expressed as severe chlorosis; 43 (with 10‐5 M) and 142 (with 10‐4 M) μg Co/g dry weight in leaves resulted in severe chlorosis. Vanadium as 10‐4 M vanadate resulted in smaller plants but not in chlorosis. Leaf, stem, and root V, respectively, were 13, 8, and 881 μg/g dry weight. Titanium was somewhat mobile with considerable yield decrease at 10‐4 M; leaf, stem, and root Ti concentrations, respectively, were 202, 48, and 2420 μg/g. Symptoms were chlorosis, necrotic spots on leaves, and stunting. Silver was very lethal at 10‐4 M AgNO3; at 10‐5 M yields were greatly decreased, but plants were grown without symptoms. Leaf, stem, and root concentrations of Ag for this treatment, respectively, were 5.8, 5.1, and 1760 μg/g dry weight. Plants grown with 10‐5 N Cr2O7 were decreased in yield by about 25% with or without EDTA (ethylenediamine tetraacetic acid) while the same level of Cr2(SO4)3 was essentially without effect. For the two salts, the leaf, stem, root concentrations for Cr, respectively were 2.2 and 1.3, 0.7 and 0. 7, and 140 and 104 μg/g. Most of the trace metals studied here had interactions in the uptake and/or distribution of other elements.  相似文献   

13.
Abstract

The seasonal patterns of foliage nutrient concentrations and contents were monitored for two growing seasons in an 11‐year—old Pinus el1iottii stand. In the first growing season after needle initiation, N, P, K, Mg, and Zn concentrations decreased, but this was followed by an increase in the fall and winter months. Another drop in concentration of all elements, except P, occurred in the second growing season. Decreases in total contents indicated that this drop was a result of translocation to other tissues. In contrast to the mobile elements, the concentration and fascicle contents of Ca, Mn, and Al increased with aging of the needles.

Between‐tree variability was least for N, P, and Zn and the N, K, Mg, Mn, and Zn in the current foliage had consistently lower variation than that in the 1‐year‐old foliage. Between‐tree variation for K was lower in the winter than the spring.

For pine foliage, recommended sampling period for N, P, Mg, and Zn is mid to late summer and for the other elements it is late fall to late winter.

There are several sources of variation that influence the level of nutrients in tree foliage. The most important of these, apart from the tree nutrient status, are seasonal fluctuations, variation between trees, and age of needles . Smaller sources of variation are associated with position of the needles within the crown, diurnal changes, year to year variation, and analytical errors1,2. These variables must be studied in order to develop suitable sampling techniques and in Pinus this has been undertaken for P. banksiana 1, P. taeda 3, P. strobus 4, P. resinosa 4, P. sylvestris 5, and P. radiata 6,7. However, foliage sampling has not been studied in detail for slash pine (Pinus elliottii Englem var. elliottii) and earlier studies with other pines have been largely confined to temperate or cool climates.

This study reports the variation in elemental concentrations with season, age of foliage, and between slash pine trees growing in a subtropical climate in Florida.  相似文献   

14.
The effects of cooking, roasting, and fermentation on the composition and protein properties of grain legumes and the characteristics of dough and bread incorporated with legume flours were determined to identify an appropriate pretreatment. Oligosaccharide content of legumes was reduced by 76.2–96.9% by fermentation, 44.0–64.0% by roasting, and 28.4–70.1% by cooking. Cooking and roasting decreased protein solubility but improved in vitro protein digestibility. Mixograph absorption of wheat and legume flour blends increased from 50–52% for raw legumes to 68–76, 62–64, and 74–80% for cooked, roasted, and fermented ones, respectively. Bread dough with cooked or roasted legume flour was less sticky than that with raw or fermented legume flour. Loaf volume of bread baked from wheat and raw or roasted legume flour blends with or without gluten addition was consistently highest for chickpeas, less for peas and lentils, and lowest for soybeans. Roasted legume flour exhibited more appealing aroma and greater loaf volume of bread than cooked legume flour, and it appears to be the most appropriate preprocessing method for incorporation into bread.  相似文献   

15.
A general method is described for determining 16 mycotoxins in mixed feeds and other food products used in the manufacture of these feedstuffs. The mycotoxins are extracted and cleaned up by extracting with solvents of different pH. Thin layer chromatography is used to separate the toxins; toxins are then quantitated by the limit detection method. The minimum detectable concentration of mycotoxins in various products is: aflatoxin B1 or G1, 4--5 micrograms/kg; ochratoxin A or ethyl ester A 140--145 micrograms/kg; citrinin 600--750 micrograms/kg; zearalenone, 410--500 micrograms/kg; sterigmatocystin, 140--145 micrograms/kg; diacetoxyscirpenol, 2400--2600 micrograms/kg; T-2 toxin, 800--950 micrograms/kg; patulin, 750--800 micrograms/kg; penitrem A 14,000--14,500 micrograms/kg; penicillic acid 3400--3650 micrograms/kg.  相似文献   

16.
The importance of dietary sulforaphane in helping maintain good health continues to gain support within the health-care community and awareness among U.S. consumers. In addition to the traditional avenue for obtaining sulforaphane, namely, the consumption of appropriate cruciferous vegetables, other consumer products containing added glucoraphanin, the natural precursor to sulforaphane, are now appearing in the United States. Crucifer seeds are a likely source for obtaining glucoraphanin, owing to a higher concentration of glucoraphanin and the relative ease of processing seeds as compared to vegetative parts. Seeds of several commonly consumed crucifers were analyzed not only for glucoraphanin but also for components that might have negative health implications, such as certain indole-containing glucosinolates and erucic acid-containing lipids. Glucoraphanin, 4-hydroxyglucobrassicin, other glucosinolates, and lipid erucic acid were quantified in seeds of 33 commercially available cultivars of broccoli, 4 cultivars each of kohlrabi, radish, cauliflower, Brussels sprouts, kale, and cabbage, and 2 cultivars of raab.  相似文献   

17.
The literature on the fluxes of six heavy metals in temperate forest ecosystems is reviewed. Special attention is given to wet and dry deposition and internal flux, to metal budgets for ecosystems and soils, to concentrations in aqueous compartments of the ecosystem and to speciation in soil solutions. Metal fluxes are discussed in relation to pollution load, soil type, tree species and land use. The mobility of Cu and Pb is strongly dependent on the solubility of organic matter. These metals are commonly accumulated in forest soils. Zinc, Cd and Ni are greatly influenced by soil acidity and are often lost in considerable amounts from acidified soils. Chromium is often at balance in forest ecosystems. Implications for metal solubility and budgets in forest soils are discussed in connection with an increase in soil acidification.  相似文献   

18.
A new HPLC procedure based on hydrophilic interaction chromatography (HILIC) has been developed for the simultaneous determination of carnosine, anserine, balenine, creatine, and creatinine in meat. This is the first time that HILIC has been directly applied to the study of meat components, having the advantage of not requiring complex cleanup and/or sample derivatization procedures. The chromatographic separation has been developed using a silica column (4.6 x 150 mm, 3 microm), and the proposed methodology is simple, reliable, and fast (<13 min per sample). The method has been validated in terms of linearity, repeatability, reproducibility, and recovery and represents an interesting alternative to methods currently in use for determining the mentioned compounds and other polar substances. The detection limits are 5.64, 8.23, 3.66, 3.99, and 0.06 microg/mL for carnosine, anserine, balenine, creatine, and creatinine, respectively.  相似文献   

19.
The volatile and soil loss profiles of six agricultural pesticides were measured for 20 days following treatment to freshly tilled soil at the Beltsville Agricultural Research Center. The volatile fluxes were determined using the Theoretical Profile Shape (TPS) method. Polyurethane foam plugs were used to collect the gas-phase levels of the pesticides at the TPS-defined critical height above a treated field. Surface-soil (0-8 cm) samples were collected on each day of air sampling. The order of the volatile flux losses was trifluralin > alpha-endosulfan > chlorpyrifos > metolachlor > atrazine > beta-endosulfan. The magnitude of the losses ranged from 14.1% of nominal applied amounts of trifluralin to 2.5% of beta-endosulfan. The daily loss profiles were typical of those observed by others for volatile flux of pesticides from moist soil. Even though heavy rains occurred from the first to third day after treatment, the majority of the losses took place within 4 days of treatment, that is, 59% of the total applied atrazine and metolachlor and >78% of the other pesticides. Soil losses generally followed pseudo-first-order kinetics; however, leaching due to heavy rainfall caused significant errors in these results. The portion of soil losses that were accounted for by the volatile fluxes was ordered as follows: alpha-endosulfan, 34.5%; trifluralin, 26.5%; chlorpyrifos, 23.3%; beta-endosulfan, 14.5%; metolachlor, 12.4%; and atrazine, 7.5%.  相似文献   

20.
This study evaluates the toxic, genotoxic/mutagenic, and antimutagenic effects of propolis extract from Amaicha del Valle, Tucumán, Argentina. The cytotoxicity assays carried out with the lethality test of Artemia salina revealed that the LD50 was around 100 microg/mL. Propolis extracts showed no toxicity to Salmonella typhimurium TA98 and TA100 strains and Allium cepa at concentrations that have antibiotic and antioxidant activities. Otherwise, for the testing doses, neither genotoxicity nor mutagenicity was found in any sample. The propolis extracts were able to inhibit the mutagenesis of isoquinoline (IQ) and 4-nitro o-phenylenediamine (NPD) with ID50 values of 40 and 20 microg/plate, respectively. From this result, the studied propolis may be inferred to contain some chemical compounds capable of inhibiting the mutagenicity of direct-acting and indirect-acting mutagens. A compound isolated from Amaicha del Valle propolis, 2',4'-dihydroxychalcone, showed cytotoxic activity (LC50 values of 0.5 microg/mL) but was not genotoxic or mutagenic. Furthermore, this compound was able to inhibit the mutagenicity of IQ (ID50 values of 1 microg/plate) but was unable to inhibit the mutagenicity of NPD. Our results suggest a potential anticarcinogenic activity of Amaicha del Valle propolis and the chalcone isolated from it.  相似文献   

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