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1.
矿质镁对水稻产量及品质影响的研究   总被引：35，自引：0，他引：35  
镁对作物正常生长发育、生理代谢、提高产量、改善产品品质具有重要作用.我国有关镁素的研究始于60年代,多见于南方红壤地区土壤镁素状况调查和镁肥肥效的研究报道.谢建昌等调查结果表明,我国广东、广西、福建等大部分植胶地的胶树出现不同程度的缺镁症状,在生产实践中镁肥效果得到了进一步的验证[1].随着农业高产品种的应用和氮、磷、钾化肥施用量的增加,作物产量不断提高,土壤养分的供给与作物对养分的需求,出现了不平衡的矛盾.为了达到平衡施肥,促进我省优质高效农业的发展,利用黑龙江省东宁县丰富的蛇纹石资源,通过特殊工艺处理,生产可被植物吸收利用的矿质镁肥,为水稻科学施肥提供依据.  相似文献   

2.
保护性耕作及氮肥运筹对玉米生长的影响   总被引：3，自引：0，他引：3  
保护性耕作(以留残茬为主要方式)具有优良的保水增产作用以及防沙固土的生态效益已多见报道.目前对于保护性耕作条件下有关作物的研究主要集中在耕作方式对作物产量、生长发育、蓄水肥田以及土壤结构等方面的影响上.多数研究认为,保护性耕作可以引起土壤温度降低,微生物数量增加及活性增强;促进作物生长发育,提高产量;节水保墒,提高水分利用率;植株残体可以培肥地力,并且长期采用保护性耕作可以明显改善土壤结构和微环境[1-3].但是其对作物品质等方面的影响研究相对较少.为此,在研究保护性耕作提高作物产量的同时开展了其对作物品质的影响;分析比较了不同耕作方式下追施氮肥对玉米组织含氮量的影响和保护性耕作条件下玉米对氮素的吸收利用效率,为保护性耕作条件下实现玉米高产优质高效生产提供技术和科学依据.  相似文献   

3.
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   

4.
硝酸根(NO-3)是化肥中常见的阴离子,也是设施土壤中积累的主要离子成分[1 - 2].硝酸盐过多不仅降低农产品品质[3],危害人类身体健康[4],还影响生态环境[5 - 6].尽管硝酸盐过多时对蔬菜作物生长发育的影响已有许多研究[7],但很少涉及作物的内源激素及叶绿体.在内源激素中,对植物逆境最敏感的是ABA[8].为此,本试验以我国北方日光温室主栽作物黄瓜为研究对象,探讨含NO-3化肥的不同施用量对其叶片ABA含量及叶绿体的影响,进一步揭示NO-3 对作物的危害机理,以期为农业生产中含NO-3化肥的合理施用提供理论依据.  相似文献   

5.
我国红壤丘陵区柑橘园土壤养分具有明显的缺磷、缺钾和有机质低等特点,土壤结构性差,"酸、干、板、粘、瘦"等特征明显[1-3],特别是新开垦的幼龄橘园,树体小、空地多,短期间种的作物收入不高,水土流失严重.通过间种绿肥或牧草等生物养地措施,可有效防治橘园的水土流失,培肥地力[3-9].在橘园间作菜肥、饲肥或粮肥等兼用经济绿肥,既能收取一定量的蔬菜或饲草获得直接经济效益,又有大量鲜嫩茎叶作肥料,培肥地力,对解决柑橘园有机肥源短缺以及季节性饲料不足,建设高产、稳产橘园等具有重要意义.为此,开展了柑橘园间作不同经济绿肥作物对柑橘产量和质量以及生态效益影响的研究,为柑橘园的科学管理提供依据.  相似文献   

6.
不同玉米基因型吸钾和耐低钾能力的研究   总被引：12，自引：1，他引：12  
利用植物对环境的遗传多样性,充分发掘优良基因型,筛选和利用吸钾能力强以及对土壤和肥料中钾利用效率高的作物品种,以适应低钾土壤条件,节约钾肥资源,缓解钾肥短缺矛盾[1 - 3].玉米是需钾量较多的作物,开展不同玉米基因型吸钾和耐低钾能力研究,挖掘玉米优良种质资源,以期为筛选吸钾能力强和耐低钾的玉米基因型,缓解我国钾肥不足提供依据.  相似文献   

7.
黄土高原旱地长期轮作与施肥土壤微生物量磷的变化   总被引：9，自引：3，他引：9  
土壤微生物量是土壤中植物有效养分的储备库,在土壤肥力和植物营养中具有重要作用[1].我国北方石灰性土壤微生物量磷为P 12.4～15.5μg/g[2],南方红壤的微生物量磷为P 12.2～31.5μg/g[3].Brookes[4]根据土壤微生物量的周转速率计算英国土壤年周转通量,发现微生物量磷周转足以提供草地所需要的磷素,即使在含量比较低的耕地土壤,微生物量磷也能够提供70%左右作物生长发育所需要的磷.可见,微生物量磷是植物非常重要的磷素营养来源.  相似文献   

8.
土壤酶素有生物催化剂之称[1-2],既参与包括土壤生物化学过程在内的自然界物质循环,又是植物营养元素的活性库[3-4].土壤酶活性与土壤状况的关系历来为各国学者所关注[5-8],应用通径分析研究土壤酶活性与土壤性质的关系也有一些报道[9-10].  相似文献   

9.
长期不同培肥黑土磷酸酶活性动态变化及其影响因素   总被引：16，自引：0，他引：16  
由于自然环境恶化和不合理的农业经营方式,导致黑土质量下降[1-2].长期以来从土壤理化性质方面对黑土质量下降原因的研究较多,而从土壤生物学活性角度研究的较少.土壤酶可使有机养分有效化,是土壤生态系统代谢过程中的重要动力.磷酸酶是土壤中最活跃的酶类之一,是表征土壤生物学活性的重要酶,在土壤磷循环中起重要作用[3-4].目前国内外对土壤磷酸酶研究主要是不同措施之间磷酸酶活性的比较,且多限于研究某一个时期磷酸酶活性,很少详细研究磷酸酶活性的动态变化.有关黑土磷酸酶活性研究相对较少且主要集中在短期不同培肥方式上.但长期施肥条件下磷酸酶活性动态变化及与土壤理化指标相关性研究未见报道.为此,本试验研究了长期不同培肥条件下不同生长季黑土磷酸酶活性变化规律及可能的机理,为进一步评价磷酸酶在黑土物质转化和能量流动中的作用提供理论依据.  相似文献   

10.
结晶有机肥对土壤供钾能力及钾在烟株的分布特点   总被引：8，自引：1，他引：8  
我国钾肥资源不足,缺钾面积大[1-2].钾是烟草品质重要指标,但国内烟叶含钾量偏低,施钾回收率往往不高[3 - 4].我国烟田土壤严重缺钾的面积达1/4,潜在缺钾面积更大[4].为解决烟叶含钾量偏低的问题,国内开展控制烟草K通道基因转移、筛选富钾育种材料和从栽培增钾渠道做了大量研究工作,但烟草钾量偏低现状仍未得到彻底解决[5].结晶有机肥在烟草生产中的应用已7年,2001年在全国11个种烟省的烟草新型肥料试验网的结果表明,它具有省肥、增产、改善烟叶品质的效果[6 - 8].最近又有报道关于结晶有机肥氮在土壤烟株中的分布[9].本文主要报道结晶有机肥对5种烟田土壤供钾能力的影响及结晶有机肥施用后,钾在烟叶中的含量和不同叶位的分布特点.  相似文献   

11.
Abstract. Two hill pastures in north Dyfed, Wales, were each treated at reseeding in 1971 with 2.25, 4.5 and 9.0 kg ha−1 cobalt sulphate. Herbage samples for analysis of Co content were taken in summer at each site from 1971 to 1976 and also at site 1 from 1977 to 1983. Acetic acid extractable Co was measured in soil samples taken each winter for the same period at both sites. At site 1, on a peat, the treatments continued to give worthwhile increases in herbage and soil Co after 13 years. At site 2, on a mineral soil, the residual effects were small and lasted no more than four years. It is suggested that me lower response and residual value at site 2 is due to higher levels of exchangeable and easily reducible manganese.  相似文献   

12.
An experiment developed in soilless culture was used to study the effect of several levels of Co2+ (0, 5, 15, and 30 mg L‐1 ) on the growth of tomato plants (Lycopersicon esculentum M. cv. Ramy). Absorption, transport, and accumulation of this metal in roots, stems, leaves, and fruits were also studied. Uptake was increased by application of this metal concentration in the nutrient solution, efficiency of root uptake of cobalt decreased with increased Co2+ treatment in the soilless culture system. The translocation of Co2+ from roots to aerial vegetative parts was increased with the time of experiment and Co2+ concentration in the nutrient solution. The presence of this metal in nutrient solution reduced tomato leaf production and elongation, specially at higher treatments.  相似文献   

13.
Cobalt (Co) is beneficial for legume plants and not an essential element for most plants. There is no sufficient information about the effect of Co stress on barley growth. The current experiment was carried out to investigate the effects of different Co levels (25, 50, 75, and 100 µM) on growth and physiological traits of three barley genotypes (B325, J36, and B340) differing in Co tolerance. The results showed that Co stress inhibited plant growth, decreased chlorophyll content and photosynthetic rate, and enhanced oxidative stress. However, the effects differed among genotypes, with B325 and B340 being the most and the least affected, respectively. Co stress caused decrease and increase of manganese (Mn) and phosphorus (P) concentrations in both roots and shoots, respectively; iron (Fe) concentration had little change in shoots and a significant decrease in roots. The current results showed a close association of Co tolerance and its accumulation in plant tissues.  相似文献   

14.
Abstract

The effect of different concentrations of cobalt added to two soil types, a sandy and a sandy loam soil, was studied on growth performance and tissue cobalt concentration of wheat plants. DTPA‐extractable cobalt was significantly higher in the sandy soil than in the sandy loam soil. Plants grown in the sandy soil accumulated significantly higher amount of cobalt in comparison to plants grown in the sandy loam soil. Roots were significantly richer in cobalt than shoots in both the soil types. Lower (1 μg g‐1) administration of cobalt resulted in an enhancement in the growth whereas higher (5–625 μg g‐1) addition inhibited growth. A significant inverse relationship between relative wheat yield and tissue cobalt concentration was observed. The results indicate a possible requirement of cobalt for higher plants.  相似文献   

15.
在潮土上采用大田小区进行了钴元素肥效试验。试验结果如下:施用适量的钴可以显著提高旗叶的叶绿素含量、硝酸还原酶活性以及小麦的根系活力;各施钴处理较对照增产7 4%～20 3%,施钴量在0 75kg/hm2以内,随着施钴量的增加,增产效应提高,当施钴量超过0 75kg/hm2时,随着施钴量的增加,冬小麦的产量增加,但增产效应下降。经回归分析,小麦产量与施钴量呈抛物线型,回归方程为y=-1263 9x2 2083 4x 4371 7,相关系数r=0 8910,达到5%显著水平。  相似文献   

16.
A method is described for the determination of cobalt in foods. After wet digestion, iron in the sample is removed by liquid-liquid extraction, and cobalt is isolated and extracted. Final determination is done by flame atomic absorption spectrophotometry. Analysis of NBS reference materials by this procedure gives results in close agreement with certified values. The limit of quantitation is 4.3 ng/mL. Recovery studies and analysis of standard materials show that this method is reliable.  相似文献   

17.
The immobilization of cobalt ion on different media to catalyze oxone has been investigated. A probe herbicide, Monuron, was effectively degraded by using Co2+/oxone systems. For Co2+ supported on zeolite, 100% of Monuron could be removed within a 10 min reaction time. However, the recycling of the spent Co-zeolite catalyst using various posttreatments did not give a promising result. This is likely because the zeolite particles in solution have blocked and significantly attenuated the incident UV light from reducing Co3+ to Co2+. On the contrary, the use of cationic resin has minimized these problems. In the process of Co-resin/oxone/UV, faster Monuron decay could be achieved than that in the dark reaction. In the presence of UV, a significant drop of total organic carbon (TOC) was also observed in this approach suggesting an effective and clean process for Monuron mineralization.  相似文献   

18.
The effect of adding cobalt, as 60Co, to the food source of the earthworm Eisenia foetida was studied. Cobalt was retained with a half-life of 387 ± 43 (SD) days in the worm. After 172 days more cobalt was concentrated in the gut than the body wall. 60Co was not transmitted from adults to cocoons. Prolonged studies involving the addition of CoCl2 (0, 8.2, 16.5 and 82.5 μg Co g?1) to a food source low in Co indicated that total Co concentrations of 17.6 and 25.9 μg g?1 resulted in significantly increased maximum weights compared to the control worms which were exposed to 9.4 μg Co g?1. The highest Co addition (82.5 μg g?1, total 91.9 μg g?1) caused no increase in maximum weight over controls, but resulted in a statistically significant lag in early growth compared to that of all other groups. Significantly more cocoons were produced by worms fed 17.6 or 25.9 μg Co g?1 compared with those fed 9.4 or 91.9 μg Co?1 Co.  相似文献   

19.
Eleven soils from Denmark and Tanzania were extracted with ammonium acetate (controls), EDTA, and dithionite-EDTA (DE) to fractionate iron (and manganese) oxides. The amounts of cobalt adsorbed and acidity desorbed by the extracted soils as well as by two synthetic iron oxides were determined, using 0.85 mM cobalt in 0.2 m NaNO3.
No significant correlations were found between cobalt adsorption and the contents of extractable manganese or organic matter, presumably because of their low contents. The major part of the cobalt adsorption (by DE-extracted samples) was due to the clay fraction and was associated with the release of approximately one proton per adsorbed Co. The remaining cobalt adsorption was attributed to the iron oxides. This portion of adsorbed cobalt was well described by considering soil iron oxides composed of only two fractions, an EDTA-extractable fraction of high reactivity and a less reactive fraction corresponding to the difference between DE-extractable iron and EDTA-extractable iron. Approximately 1.7 protons were released per Co adsorbed by these iron oxide fractions and by the synthetic iron oxides.
The amounts of cobalt adsorbed by the soil iron oxides were well predicted from the contents and specific surfaces of the two iron oxide fractions together with the specific cobalt adsorption of synthetic iron oxides.  相似文献   

20.
The effects of cobalt chloride on the production of trichothecene and ergosterol in Fusarium graminearum were examined. Incorporation experiments with (13)C-labeled acetate and leucine confirmed that both 3-acetyldeoxynivalenol and ergosterol were biosynthesized via a mevalonate pathway by the fungus, although hydroxymethyl-glutaryl CoA (HMG-CoA) from intact leucine was able to be partially used for ergosterol production. Addition of cobalt chloride at concentrations of 3-30 μM into liquid culture strongly enhanced 3-acetyldeoxynivalenol production by the fungus, whereas the amount of ergosterol and the mycelial weight of the fungus did not change. The mRNA levels of genes encoding trichothecene biosynthetic proteins (TRI4 and TRI6), ergosterol biosynthetic enzymes (ERG3 and ERG25), and enzymes involved in the mevalonate pathway (HMG-CoA synthase (HMGS) and HMG-CoA reductase (HMGR)) were all strongly up-regulated in the presence of cobalt chloride. Precocene II, a specific trichothecene production inhibitor, suppressed the effects of cobalt chloride on Tri4, Tri6, HMGS, and HMGR, but did not affect erg3 and erg25. These results indicate that cobalt chloride is useful for investigating regulatory mechanisms of trichothecene and ergosterol production in F. graminearum.  相似文献   

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