葡萄根系对锰胁迫的生理反应

以葡萄水晶、金手指、康拜尔为材料,采用沙培试验法,探讨了葡萄根系对锰胁迫的生理反应。结果表明:随着锰质量浓度的升高,3种葡萄根系活力均呈先升后降的趋势,在锰的质量浓度为5 g/L时其根系活力达到最大。锰处理整体上增加了3种葡萄根中MDA含量。在锰胁迫下,PAL活性在不同品种间呈现出不同的变化:水晶和康拜尔先升高后降低,金手指却恰恰相反。总之,金手指根系对锰胁迫最敏感,更易受到伤害,而水晶和康拜尔却不太敏感,说明水晶和康拜尔对锰胁迫有较强的耐性。     

断奶仔猪对不同锰源生物学利用率的研究

本试验旨在研究断奶仔猪对甘氨酸锰和复合氨基酸锰(有机锰源)相对无机硫酸锰的生物学利用率。采用3×2两因子完全随机设计,将224头体况良好、体重相近(9.67±0.13)kg三元杂交(杜×长×大)断奶仔猪分成7个处理组,每个处理4个重复。对照组饲喂不额外添加锰的基础日粮(锰含量为39.22 mg/kg),试验组在对照组的基础上分别以无机硫酸锰、甘氨酸锰和复合氨基酸锰的形式添加20、40 mg/kg。预饲期7 d,正饲期28 d。结果表明,锰源及锰源与锰水平的互作对断奶仔猪的生产性能、血清锰含量、锰超氧化物歧化酶(Mn-SOD)活性及肾脏、心脏、胰脏锰含量均无显著影响(P>0.05),但肝脏和跖骨锰含量受锰源及锰水平的影响显著(P<0.05),根据肝脏锰和跖骨锰含量与日粮锰进食量之间拟合的多元线性回归,运用斜率比率法,计算甘氨酸锰和复合氨基酸锰相对无机硫酸锰(100%)的生物学利用率分别是125.95%,112.79%和133.08%,119.25%,表明断奶仔猪对甘氨酸锰和复合氨基酸锰的生物学利用率显著高于无机硫酸锰(P<0.05),但有机锰源间无显著差异(P>0.05)。     

锰与硼喷施对紫花苜蓿产量和矿质元素含量的影响

采用叶面喷施的方法,研究不同水平锰与硼对紫花苜蓿草产量和矿质元素含量的影响.结果表明,喷施锰、硼促进了紫花苜蓿草产量的增加,适量则效果显著(P < 0.05),以施锰浓度200 mg·L-1(Mn2处理)和硼浓度600 mg·L-1(B3处理)效果最好,草产量比对照分别提高809.49和1 065.35 kg·hm-2;喷施锰肥能显著提高锌和锰的含量;适量则能显著提高紫花苜蓿磷、钴、硒、铁和钼的含量,喷施锰肥降低了钙和铜的含量,适量则影响显著;喷施锰肥,硼的含量略有降低;且锰含量与施锰量呈正相关,硒、铜含量与施锰量呈负相关;而铁、锌含量随施锰量增加呈先升后降趋势.喷施硼肥显著提高了锌和磷含量,显著降低了钙、钼、硒的含量,显著提高钴、铁、锰、硼的含量,喷施硼肥,铜的含量略有下降;且锌、硼含量与施硼量呈正相关,铁、钙、钼、铜、硒含量与施硼量呈负相关;而锰、磷含量随施硼量增加呈先升后降趋势.     

籼稻铁、锌、锰和铜含量分析

对广东省农科院水稻研究所品种资源库保存的186份材料的铁、锌尧锰和铜含量进行测定,并对它们之间的相关性进行分析。结果显示,稻米中微量元素含量主要由品种的遗传特性决定,稻米中铁、锌尧锰、铜等微量元素的含量存在极显著的基因型差异。比较不同类型品种Fe、Mn、Cu和Zn平均含量,白米和黑米之间Mn和Cu含量差异不显著,而黑米Fe和Zn含量则显著高于白米;黑米糯稻Fe和Zn含量显著高于白米糯稻,两者之间的Mn和Cu含量则无显著差异。相关分析结果显示品种Fe与Zn、Mn与Cu之间的相关性均达极显著水平,Cu与Zn之间相关性达显著水平;Fe与Mn、Fe与Cu、Mn与Zn的相关性未达显著水平。精米中Fe、Mn、Cu和Zn含量显著低于糙米中的含量。     

硅对赤红壤中锰的解毒效应研究

采用培养试验方法研究了硅肥对酸性土壤中锰毒性的影响, 旨在为酸性土壤锰毒害的防控提供科学依据。结果表明,甘蔗的根际效应明显, 根际土壤中的pH值、有效硅含量较低而活性锰及水溶态锰、交换态锰、有机结合态锰、碳酸盐结合态锰、铁锰氧化态锰含量均显著高于土体。然而,施用硅肥(偏硅酸钠)后,土壤活性锰含量和水溶态、交换态尧、机结合态锰含量均显著降低, 但是硅肥对根际土壤锰含量和形态的效应弱于土体;并且,施用硅肥使甘蔗地上部锰含量(47.1~112.1 mg/kg)显著降低, 并且有随着硅肥用量(0.5~2.1 g/kg)增加而降低的趋势;虽然硅肥的施用也减少甘蔗地上部铁的含量, 但铁锰比值却从对照的2.51 增加至2.92~5.72 之间。因此,施用硅肥后甘蔗株高、总生物量分别提高4.07%~15.24%、8.41%~28.03%。可见, 硅肥的施用减轻了酸性土壤中锰的毒害。     

The relationship between phosphorus and copper concentrations in wheat

Abstract

Poorly managed kaolinitic soils are often too low in P and K for optimum agronomic crop production. Even though many of these soils have relatively high phosphate fixing capacities, P applied at sufficient rates to increase soil P to acceptable levels may induce micronutrient deficiencies. The purpose of this study was to evaluate the effects of applied and residual P on Mn, Zn, and Cu uptake by field grown wheat (Triticum aestivum). Treatments were a one‐time application of P (0, 64, 128, 256, and 384 kg/ha P) and K (0, 110, 220, 440, and 660 kg/ha K) rates arranged in a 5×5 complete factorial. The treatments were applied in October, 1977 and the study was continued through June, 1979. Potassium and P × K interactions did not have a significant effect on Mn, Zn, or Cu uptake. Phosphorus did not affect Mn concentration in the wheat tissue but Zn and Cu concentrations generally decreased as applied and residual soil P levels increased. The tissue Zn concentration at the various plant growth stages did not decrease below defined critical levels. The Cu concentration decreased linearly with applied P and curvilinearly with residual P. The tissue Cu levels often decreased below suggested critical levels. Total Cu in the wheat tissue indicated that the decrease in Cu concentration as P levels increased was not a simple dilution effect resulting from increased plant growth as applied and residual soil P increased.     

A comparison of Mehlich I and Mehlich III extractants as predictors of manganese,copper and zinc availability in four Delaware soils

Abstract

The relative effectiveness of Mehlich I (.025N H₂SO₄ + .05N HCl) and Mehlich III (0.2N CH₃COOH + 0.25N NH₄NO₃ +.015N NH₄F + .013N HNO₃ + .001M EDTA) extractants as predictors of Mn, Cu and Zn uptake was assessed in a greenhouse experiment with four Delaware soils. The soils were adjusted to eight pH levels by addition of Ca(OH)₂ or elemental S, and received comparable amounts of Mn, Cu and Zn as either (1) MnSO₄ + CuSO₄ + ZnSO₄ or (2) Poultry Manure. Mehlich 1 and III extractable Mn and Zn, but not Cu, were well correlated in most instances. Excellent correlations were obtained between Mn uptake and Mehlich I and Mehlich III extractable Mn, for all soils and sources. In general, however, neither Zn nor Cu was found to correlate well with plant uptake. Based on this study, conversion to Mehlich III, as a routine soil test extractant for micronutrients, would not result in a significant improvement over the currently used Mehlich I extractant.     

Cadmium sulfate application to sludge‐amended soils: III. Relationship between treatment and plant available cadmium,zinc, and manganese1

Abstract

Swiss chard (Beta vulgarisvar. cicla) and corn (Zea maysL.) were used as biological indicators of Cd, Zn and Mn availability in 12 soils amended with and without sludge, CdSO₄and CaCO₃. Soil Cd, Zn and Mn were partitioned into six fractions: soluble, exchangeable, adsorbed, organically bound, carbonate bound and sulfide bound, by the use of H₂O, KNO₃, H₂O, NaOH, EDTA and HNO₃, respectively. The data indicate that the major portion of total Cd was found in the carbonate, residual and organic fractions. Addition of CaCO₃caused an increase in the soluble and exchangeable fractions of Cd in the soils. The concentrations of Cd in the saturation extracts of the limed soils were significantly greater than those of the unlimed soils; however, this was not reflected in greater plant uptake of Cd from limed soils.     

锰,锌,铜对肉用仔鸡营养效应的研究

选用１日龄ＡｒｂｏｒＡｃｒｅｓ（ＡＡ）肉用商品一代雏鸡,采用玉主－－豆粕型为基础的全价日粮。在全价日粮基础上,研究添加中剂量向量元素锰、锌、铜对肉用仔鸡生产性能、血清指标及组织中向量元素含量的影响。结果表明,采食量和饲料为差很小,添加锰能明显地减少腿病发生率,当日粮中的锰含量为１３７ｍｇ／ｋｇ或更高时,腿病发生率从３８．５％降至１０％以下。铜也能使腿病发生率降低,但不及锰的效果。骨铜含量和骨甸含量     

Effect of magnesium fertilization on yield and leaf composition of tomato plants

Tomato plants were grown for 2 years at 4 different rates of Mg fertilization on a Princeton loamy sand at pH 4.8 with 29 kg exchangeable Mg/ha. Calcareous limestone was used to provide a pH treatment in the second year. Magnesium deficiency symptoms were observed on plants grown on plots having ≤ 38 kg/ha NH₄OAC‐extractable Mg. Application of 56 kg Mg/ha corrected Mg deficiency and produced a significant increase in yield. Application of calcitic limestone also produced significant yield increases, but did not affect the development of Mg deficiency symptoms. Tomato yield was increased 27.9% by Mg application and 17.7% by lime application. Highest tomato yield was obtained with application of 112 kg Mg/ha. Symptoms of Mg deficiency were observed when the Mg concentration in recently mature leaf tissue was in the 0.30 to 0.32% range. Magnesium concentration in leaf tissue increased linearly with increasing Mg rate. Leaf Mg concentration at various growth stages of the tomato plant was variable depending on Mg treatment. Magnesium fertilization rate bad little effect on Ca or K leaf concentrations. Application of Calcltic limestone increased leaf tissue Ca and reduced leaf tissue Mg and Mn concentrations.