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1.
花生-甘薯轮作制平衡施肥模式的研究   总被引:6,自引:0,他引:6  
花生、甘薯是南安市重要的旱地作物,年种植面积都在1.67万hm2以上,随着作物结构调整,种植面积将进一步扩大,而花生、甘薯轮作是主要耕作方式之一.  相似文献   

2.
富磷垃圾肥对大豆营养及产量、品质的影响   总被引:5,自引:2,他引:5  
我国有74%的耕地土壤缺磷,在农业种植中磷素的利用率又极低,当季利用率仅为10%~25%,是作物产量的重要限制因子[1].目前,我国农用磷肥主要是磷矿粉经加工而成,需要大量硫酸,生产成本较高,长期施用不仅造成土壤板结,也会污染环境.磷矿粉如直接施用于土壤时,肥效又受许多因素限制[2].如何在我国磷资源有限的情况下研究和总结一套能在农业生产中应用的生物学途径,以维持土壤的磷供应水平,是广大科研工作者普遍关心的课题.城市生活垃圾在堆肥过程中将产生大量的有机弱酸类物质,其对难溶性磷的溶解能力已在土壤中得到证实[3-5];另外堆肥过程中产生的腐殖酸类物质也可以对难溶性磷有一定的络合能力[6];同时,堆肥过程中微生物的活动也可将一部分磷固定在体内.因此,通过生活垃圾堆肥对难溶性磷进行转化,可使堆肥中形成较多的易矿化的有机态磷及可溶性磷,施用于土壤后可提高磷素的有效性.本研究通过利用生活垃圾堆肥与难溶性磷生产富磷垃圾肥,并进行田间试验,探讨富磷垃圾肥对大豆营养物质的积累、作物产量及质量的影响.  相似文献   

3.
硼对甘蓝型油菜不同品种苗期生理特性的影响   总被引:15,自引:4,他引:11  
油菜是我国的主要油料作物之一,种植面积和总产量均居世界首位.油菜也是需硼较多的作物,我国几乎所有油菜主要产区都存在不同程度的土壤有效硼不足现象,严重影响油菜生产[1].80年代中期在推广单低、双低油菜品种时发现优质油菜品种比普通油菜对缺硼反应更敏感,随后我国不少地方开展了油菜缺硼基因型差异的研究[2~4]  相似文献   

4.
土壤过量施用肥料,使部分菜地特别是保护地土壤中氮、磷养分积累过剩,导致蔬菜品质变劣,肥效下降,病虫害增多[1-2]。上世纪80年代日本已报道菜地过剩营养的不利影响,发现在土壤磷过高时,微量元素锰和铁出现异常[3]。据统计,京郊菜地土壤氮、磷养分已有明显积累,全市平均保护地土壤有效磷(P)含量达97·1mg/kg,个别区县高达165·8 mg/kg;土壤NO3-N含量平均为88·8 mg/kg,个别区县高达168 mg/kg[4]。在这种高氮、磷含量的土壤中,其它养分的变化也有必要进行研究。相对于大量元素,菜地土壤微量元素的研究较少[5],而且一般都是在常规施肥量的条…  相似文献   

5.
水稻硅、锌、锰配施效应   总被引:4,自引:0,他引:4  
  相似文献   

6.
集约经营雷竹林土壤氮素状况及氮平衡的估算   总被引:7,自引:0,他引:7  
雷竹(Phyllostachy Praecoxf.preveynalis Chen etYao)别名雷公竹,是禾本科竹亚科刚竹属竹种,是我国优良笋用散生竹种之一[1]。原来主要分布在浙江省临安、德清等地,已有200多年的栽培历史。改革开放以来,推广了以大量施肥和冬季覆盖为主要内容的集约经营技术,使雷竹提早出笋,提高了产量和经济价值[1-2],成为农民致富的一种新兴产业。如今已迅速扩散到我国安徽、江苏等十一省市,大多数地区均报道种植成功,获得好收成。据调查竹农平均亩产值8000~10000余元,纯盈利7000~9000元,有的超过万元[2]。有关林、农业部门及院校对其丰产栽培技术[1-3…  相似文献   

7.
8.
天鹰椒的营养特性与氮磷肥料效应   总被引:1,自引:0,他引:1  
天鹰椒(Capsicum frutescens var.fasciculatum),又名朝天椒,枥木三鹰椒, 是簇生辣椒中的一个变种.河北、山东、河南、山西、辽宁、新疆大量种植,现已发展成为我国出口创汇的一个主要产品.但由于对其营养特性了解不足,盲目施肥,产量多是低而不稳.对于鲜辣椒的营养特性虽有报道[1, 2],但对于干辣椒,特别是对于天鹰椒根茎、叶片、果实N、P、K、Ca、Mg吸收的研究,尚少见报道.为此,我们于1999~2000年对天鹰椒的营养特性及肥料效应进行了研究,以期为天鹰椒的优质高产提供依据.  相似文献   

9.
柴胡氮、磷和有机肥施肥效应分析   总被引:1,自引:1,他引:1  
柴胡(Bupleurum chinenseDC.)为伞形科柴胡属植物,为我国、日本和韩国等国常用大宗药物,在《神农本草经》中被列为上品[1]。国内外有关柴胡的研究集中于其化学成分、药理作用及临床应用方面,而栽培育种等方面的研究较少;施肥对柴胡生长发育及有效成分影响方面的研究更少[2]。在柴胡栽培中,作为技术核心的施肥技术仍存在较大盲目性,施肥种类和配比不合理成为影响药材质量的重要原因。运用现代植物营养研究方法,探讨柴胡的最佳施肥方案,促进其产量和质量的提高成为亟待解决的问题。据此,结合产量和质量指标,在陕西省商洛市进行柴胡氮、磷、…  相似文献   

10.
新型包膜复合肥在地毯草上的应用研究   总被引:2,自引:0,他引:2  
我国城镇绿化面积不断扩大[1-5]。其中一大部分是种植草坪,随之而来的就是草坪的施肥问题。我国生产和使用的草坪专用肥料很少,大多为常规速效复合肥,施肥不当不仅会给环境造成面源污染[6],而且影响绿化质量。针对草坪的营养特点,我们研制出包膜控释草坪专用肥料[7],并分析了其在地毯草上的应用效果。1材料与方法1·1试验材料供试土壤采自沈阳农业大学后山棕壤试验地0—20 cm耕层。该土壤为发育在第四纪黄土性母质上的简育湿润淋溶土(耕作棕壤)。其基本农化性质如下:全N 1·81 g/kg,碱解N 94·6 mg/kg,有效P15·69 mg/kg,速效K 101·4 mg/…  相似文献   

11.
Heat and alkali treatments of foods, widely used in food processing, result in the formation of dehydro and cross-linked amino acids such as dehydroalanine, methyldehydroalanine, beta-aminoalanine, lysinoalanine (LAL), ornithinoalanine, histidinoalanine (HAL), phenylethylaminoalanine, lanthionine (LAN), and methyl-lanthionine present in proteins and are frequently accompanied by concurrent racemization of L-amino acid isomers to D-analogues. The mechanism of LAL formation is a two-step process: first, hydroxide ion-catalyzed elimination of H(2)S from cystine and H(2)O, phosphate, and glycosidic moieties from serine residues to yield a dehydroalanine intermediate; second, reaction of the double bond of dehydroalanine with the epsilon-NH(2) group of lysine to form LAL. Analogous elimination-addition reactions are postulated to produce the other unusual amino acids. Processing conditions that favor these transformations include high pH, temperature, and exposure time. Factors that minimize LAL formation include the presence of SH-containing amino acids, sodium sulfite, ammonia, biogenic amines, ascorbic acid, citric acid, malic acid, and glucose; dephosphorylation of O-phosphoryl esters; and acylation of epsilon-NH(2) groups of lysine. The presence of LAL residues along a protein chain decreases digestibility and nutritional quality in rodents and primates but enhances nutritional quality in ruminants. LAL has a strong affinity for copper and other metal ions and is reported to induce enlargement of nuclei of rats and mice but not of primate kidney cells. LAL, LAN, and HAL also occur naturally in certain peptide and protein antibiotics (cinnamycin, duramycin, epidermin, nisin, and subtilin) and in body organs and tissues (aorta, bone, collagen, dentin, and eye cataracts), where their formation may be a function of the aging process. These findings are not only of theoretical interest but also have practical implications for nutrition, food safety, and health. Further research needs are suggested for each of these categories. These overlapping aspects are discussed in terms of general concepts for a better understanding of the impact of LAL and related compounds in the diet. Such an understanding can lead to improvement in food quality and safety, nutrition, microbiology, and human health.  相似文献   

12.
Among plant-derived odorants, damascenone is one of the most ubiquitous, sometimes occurring as an apparent natural product but more commonly occurring in processed foodstuffs and beverages. It has been widely reported as a component of alcoholic beverages, particularly of wines made from the grape Vitis vinifera . Although damascenone has one of the lowest ortho- and retronasal detection thresholds of any odorant, its contribution to the sensory properties of most products remains poorly understood. Damascenone can be formed by acid-catalyzed hydrolyses of plant-derived apocarotenoids, in both aglycon and glycoconjugated forms. These reactions can account for the formation of damascenone in some, but not all, products. In wine, damascenone can also be subject to degradation processes, particularly by reaction with sulfur dioxide.  相似文献   

13.
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   

14.
Nitrofurans were broadly used as an extremely effective veterinary antibiotic especially in pig and poultry production farms. Because of fears of the carcinogenic effects on humans, the nitrofurans were banned from use in livestock production in many countries, including the European Union. The present study examines the accumulation, distribution, and depletion of furaltadone and nifursol and of their tissue-bound metabolites [3-amino-5-morpholinomethyl-2-oxazolidinone (AMOZ) and 3,5-dinitro-salicylic acid hydrazine (DNSAH), respectively, in poultry edible tissues (muscle, liver, and gizzards) following administration to chickens of therapeutic and subtherapeutic concentrations of both compounds. Nitrofurans determination was performed by high-performance liquid chromatography-diode array detection and liquid chromatography-tandem mass spectrometry, respectively, for feeds and for poultry tissues. Furaltadone and nifursol, in very low concentrations, were found in samples of muscle, liver, and chicken's gizzard collected from slaughtered animals after 5 weeks of treatment and no withdrawal time period. When a withdrawal time period of 3 weeks was respected, no detectable nitrofuran parent compounds was observed in all of the studied matrices. For AMOZ, concentrations of 270 μg/kg in meat, 80 μg/kg in liver, and 331 μg/kg in gizzard were determined after administration of a medicated feed with furaltadone (132 mg/kg), 3 weeks after withdrawal of treatment. For DNSAH, the concentration values obtained are much lower than those observed for AMOZ. For meat, liver, and gizzard, DNSAH concentrations of 2.5, 6.4, and 10.3 μg/kg, respectively, were determined, after administration of a medicated feed with nifursol (98 mg/kg), 3 weeks after withdrawal of treatment. The gizzard could be considered a selected matrix for nitrofuran residues evaluation in poultry, due to its capacity of retaining either nitrofuran parent compounds or metabolites in higher concentrations, regardless of the administered dose or of the respected withdrawal time period.  相似文献   

15.
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   

16.
This study was designed to estimate the dietary intake of arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) by the general population of Catalonia, Spain. The concentrations of these elements were determined in food samples randomly acquired in seven cities of Catalonia between June and August 2000. A total of 11 food groups were included in the study. As, Cd, Hg, and Pb levels were measured by ICP-MS and AAS. The dietary intake of these elements was determined by a total diet study. Calculations were carried out on the basis of recent data on the consumption of the selected food items. Trace element intake was estimated for five population groups: children, adolescents, male and female adults, and seniors. The highest dietary intakes of As (223.6 microg/day), Cd (15.7 microg/day), Hg (21.2 microg/day), and Pb (28.4 microg/day) corresponded to male adults. For all analyzed elements, fish and shellfish was the group showing the highest contribution to the respective intakes. In comparison with previous results, a general decrease in As, Cd, Hg, and Pb intake has occurred. The dietary intake of these elements was also compared with the provisional tolerable weekly intake (PTWI). Dietary intakes of As, Cd, Hg, and Pb by the population of Catalonia are currently well below the respective PTWIs.  相似文献   

17.
A liquid chromatographic procedure has been developed for the assay, content uniformity, and identification of single active ingredient formulations of desipramine, fluphenazine, and promazine. The drugs are extracted from formulations with methanol or dilute hydrochloric acid and quantitated against an internal standard (norephedrine). The drugs are identified by comparison of retention times with those of the reference standards.  相似文献   

18.
Barley (Hordeum vulgare L.) is a cereal grown for animal feed, human consumption, and malting. Nutrient concentrations are important as they provide information regarding the dietary values of barley consumed by animals or human beings. In addition, grain nutrient removal may be useful for refining fertilizer recommendations. A study was conducted in 2015 and 2016 investigating the cultivar effects on grain yield, quality, and grain nutrient concentrations and removal under irrigated conditions for two-row barley cultivars. Adjunct and feed cultivars produced the highest yields compared with the all-malt and food cultivars. Specific quality and nutrient values were greater than or equal to in the food cultivar compared to the malt or feed cultivars. Variations in nutrient concentrations were measured among the adjunct and all-malt cultivars, which could potentially affect the malting and brewing qualities. Grain yield, quality, nutrient concentrations and nutrient removal varied among cultivars grown under identical environmental conditions, which may influence end-use.  相似文献   

19.
The total phenolics and antioxidant activities of fenugreek, green tea, black tea, grape seed, ginger, rosemary, gotu kola, and ginkgo extracts, vitamin E, and tert-butylhydroquinone, were determined. Grape seed and green tea were analyzed for their phenolic constituents using high-performance liquid chromatography. The total phenolics of the plant extracts, determined by the Folin-Ciocalteu method, ranged from 24.8 to 92.5 mg of chlorogenic acid equivalent/g dry material. The antioxidant activities of methanolic extracts determined by conjugated diene measurement of methyl linoleate were 3.4-86.3%. The antioxidant activity of the extracts using chicken fat by an oxidative stability instrument (4.6-10.2 h of induction time) followed a similar trend in antioxidant activity as determined by the Folin-Ciocalteu method. Seven phenolics in grape seed and green tea extracts were identified that ranged from 15.38 to 1158.49 and 18.3 to 1087.02 mg/100 g of extract, respectively. Plant extracts such as green tea and grape seed extracts can be used to retard lipid oxidation in a variety of food products.  相似文献   

20.
The effect of potassium azide (KN3), O,O-diethyl O-(2-isopropyl-6-methyl-4-pyrimidinyl) phosphorothioate (diazinon), O,O-diethyl S-[(ethylthio)- methyl] phosphorodithioate (phorate), 1-naphthyl methylcarbamate (carbaryl), and p-chlorophenyl methylcarbamate (PCMC) on the biodegradation and persistence of several amide, carbamate, and urea herbicides in soil and microbial culture systems was examined. KN3 inhibited the biodegration of isopropyi m-chlorocarbanilate (chlorpropham) in both soil perfusion and microbial culture system, but was limited in increasing chlorpropham persistence in soil under greenhouse conditions. PCMC and diazinon, inhibited the metabolism of chlorpropham by isolated cultures of soil bacteria (Pseudonwnas striata Chester and Achromobacter sp). Phorate inhibited chlorpropham metabolism by P. striata, but did not inhibit chlorpropham metabolism by Achromobacter sp. Carbaryl, PCMC, and diazinon increased the persistence of chlorpropham in soil under greenhouse conditions. PCMC also inhibited the microbial metabolism of isopropyl carbanilate (propham), 3',4'-dichloropropionanilide (propanil), 2-chloro-N,N-diallylacetamide (CDAA), 1,1-dimethyl-3 (α,ga,α-trifluoro-m-tolyl)urea (fluometuron) and 3-(3,4-dichlorophenyl)-1,1-dimethylurea (diuron), but not that of 2-chloro-N-isopropylacetanilide (propachlor) in isolated culture systems.  相似文献   

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