Molybdenum-enriched soybean seeds enhance N accumulation, seed yield, and seed protein content in Brazil

High soybean yields require large amounts of nitrogen (N), which can be obtained mainly from symbiotic N₂ fixation. However, the efficiency of this biological process can be limited by micronutrient deficiencies, especially of molybdenum (Mo). In Brazil, soybean generally responds positively to fertilization with Mo in soils of low fertility and in fertile soils depleted of Mo due to long-term cropping. The micronutrient can be supplied by seed treatment, however toxicity of Mo sources to Bradyrhizobium strains applied to seed as inoculant has been observed, resulting in bacterial death and reductions in nodulation, N₂ fixation and grain yield. Therefore, use of seeds enriched in Mo could be a viable alternative to exterior seed treatment, allowing elite inoculant strains of Bradyrhizobium to sustain high rates of biological N₂ fixation. We demonstrated the feasibility of producing Mo-rich seeds of several soybean cultivars, by means of two foliar sprays of 400 g Mo ha⁻¹ each, between the R3 and R5 stages, with a minimum interval of 10 days between sprays. As a result of this method, considerable increases in seed-Mo content were obtained, of as much as 3000%, in comparison to seeds obtained from plants which received no Mo. In field experiments performed in soils with low N content and without any N-fertilizer supply, inoculation of Mo-rich seeds produced plants with increased N and Mo contents in the grain and higher yields of total N and of grain. In most cases, Mo-rich soybean seeds did not require any further application of Mo-fertilizer.     

珠江三角洲菜园土硼和钼测土施肥技术指标研究

在不同地点、不同肥力水平的菜园土上进行代表性蔬菜微肥田间试验,对23个试验点的蔬菜相对产量与施硼、钼量,以及土壤有效硼、钼含量等试验数据进行相关统计分析,建立回归方程,以此建立菜园土有效硼和钼养分丰缺指标和各等级土壤的推荐施硼、钼指标:①蔬菜相对产量为50%、50%～75%、75%～90%、90%～95%、95%的各肥力等级菜园土壤有效硼丰缺指标分别为0.05mg·kg-1、0.05～0.20mg·kg-1、0.20～0.45mg·kg-1、0.45～0.65mg·kg-1、0.65mg·kg-1,各有效硼等级对应的施硼量分别为75g·(667m2)-1、50～75g·(667m2)-1、32～50g·(667m2)-1、26～32g·(667m2)-1、0～26g·(667m2)-1。②土壤有效钼丰缺指标分别为0.01mg·kg-1、0.01～0.07mg·kg-1、0.07～0.24mg·kg-1、0.24～0.35mg·kg-1、0.35mg·kg-1,各有效钼等级所对应的施钼量分别为12.5g·(667m2)-1、10.5～12.5g·(667m2)-1、9.5～10.5g·(667m2)-1、9.0～9.5g·(667m2)-1、0～9.0g·(667m2)-1。     

硼钼肥对旱地花生生长发育及产量的影响

旱(薄)地条件下,研究了叶面喷施硼肥和钼肥对春播和夏播花生生长发育及产量的影响。结果表明:无论春播还是夏播,施肥处理的多数农艺性状明显好于对照,但不同施肥处理间存在较大差异,其中硼钼肥配施对花生营养性状的促进作用优于单施钼肥或硼肥,春、夏播结果一致;单施硼肥有利于提高春花生单株结荚数,单施钼肥有利于饱果率,硼钼配施有利于同时提高单株结荚数和饱果率;硼钼配施或单施硼肥有利于提高夏花生双仁果率,单施钼肥对提高夏花生产量性状无明显影响;春、夏播4个施肥处理产量,以硼钼配施的处理最高,比对照平均增产12.0%,其次为单施硼肥,比对照平均增产7.0%,单施钼肥春播增产5.6%,夏播无明显增产作用。因此,生产中应注意硼钼肥配施。     

钼对鸡肝肾组织形态学的影响

为研究钼对鸡肝肾组织形态学的影响,选取80只健康2w龄雏公鸡,随机分为5组,每组16只。通过在饮水中添加不同剂量的钼酸钠(以钼离子计),建立试验动物模型:对照组(钼:0mg.L-1)、钼Ⅰ组(钼:12.5mg.L-1)、钼Ⅱ组(钼:25.0mg.L-1)、钼Ⅲ组(钼:50.0mg.L-1)、钼Ⅳ组(钼:100.0mg.L-1)。分别在试验处理第10w,采集鸡的肝脏和肾脏,固定包埋处理后,制得切片,经HE染色分析,用显微镜观察鸡肝肾组织形态学变化。肾脏和肝脏的组织形态学观测结果显示:加钼的各组与对照组相比,细胞数量增多,且有浓染,出现坏死现象,细胞核皱缩加剧,有少量充血。试验低剂量(钼Ⅰ组、钼Ⅱ组)下的钼导致鸡肝肾组织发生不明显的病理形态学变化,而高剂量组(钼Ⅲ组、钼Ⅳ组)发生明显的病理形态学变化。     

钼酸铵喷施时期和浓度对大豆生长·产量和品质的影响

采用随机区组设计,研究了钼肥喷施时期和浓度对大豆生长、产量及品质的影响。结果表明:各处理根瘤数、叶绿素含量、叶面积系数较对照均有增加;施肥浓度处理以A2(0.1%浓度喷施)水平产量最高;施肥时期处理以B(2盛花期)水平产量最高。A2B2为最佳的处理组合,较A1B1增产583.625 kg/hm2,增幅为24.36%,各处理间蛋白质含量差异均达极显著水平。A3B3蛋白质含量最高,较A1B1蛋白质含量提高9.7%。脂肪含量各处理间差异不显著。     

Effect of Root Zone Temperature on Accumulation of Molybdenum and Nitrogen Metabolism in Potato Plants

Abstract

Changes in root temperature caused by the application of plastic covers were studied in relation to the uptake and content of molybdenum (Mo) in the different organs of potato (Solanum tuberosum L. var. Spunta) plants (roots, tubers, stems, and leaves) and in relation to nitrogen (N) metabolism. For the semi‐forcing technique of mulching, four different covers were used: T ₁ (transparent polyethylene), T ₂ (white polyethylene), T ₃ (coextruded black and white polyethylene), and T ₄ (black polythylene). The control treatment had no mulch. The results revealed a positive and significant effect of plastic covers on root temperatures: T ₀ = 16°C, T ₁ = 20°C, T ₂ = 24°C, T ₃ = 27°C, T ₄ = 30°C. These thermal differences significantly influenced the Mo concentration, particularly in the T ₂ and T ₃ treatments in the leaves, roots, and tubers. The same temperatures significantly altered N metabolism in both the aerial and underground parts of the plants, and a strong interrelationship was found between Mo and nitrate reductase (NR) activity. The mulching of this crop proved to be a promising technique in phytoremediation.     

高钼环境分布与家畜钼中毒研究

陕西省境内某钼矿的选矿废水常年排放到南洛河,污染了河水。家畜饮用污染废水或采食河边牧草后即发生以腹泻为主的钼中毒,发病率达18.74％,死亡率为9.41％,使该地区畜牧业损失严重。经对15个品种219份样品1800余样次毒源成分分析检测,结果表明,钼在水、土壤、植物和动物组织中的含量均属高浓度水平。家畜饮用含有高钼污水,摄入的钼量极易达到中毒标准而致病。冶金工业污染引起高水平钼在食物链上正相关分布与迁移即为中毒原因。单纯饮用高钼污水完全能够引起反刍动物中毒。     

硼、钼营养对甘蓝型油菜脂肪酸组分的影响

盆栽试验研究表明:硼、钼及其配合施用使甘蓝型油菜中双6号和中油821的含油量提高4.3%～6.2%,并提高油酸含量,降低芥酸和亚麻酸含量.比较两品种不同施肥处理的效果发现,单施硼肥对提高中油821含油量的效果高于其它处理;单施钼肥对中双6号的含油量及油酸和芥酸含量有显著的影响,而对中油821的影响不显著.综合分析认为,硼、钼配合施用对中油821的品质效应好于中双6号.     

钼肥对鲜食大豆主要光合生理指标的影响

为了明确钼肥对鲜食大豆光合生理指标的影响,选用鲜食大豆品种抚鲜3号和日本青作为试验材料,分别在不同生育时期(V5、R1、R3、R5、R6),测定C1(0 kg·hm-2)、C2(0.3 kg·hm-2)、C3(1.5 kg·hm-2)、C4(3.0 kg·hm-2)四种施钼处理下上述鲜食大豆品种的叶面积指数、叶绿素含量、光合速率、气孔导度、胞间CO2浓度、蒸腾速率,考察了施钼量与光合指标的关系以及生育期内鲜食大豆光合效率的变化规律。结果表明:施钼提高了鲜食大豆叶片的叶面积指数、叶绿素含量、光合速率、气孔导度、蒸腾速率,延缓了鲜食大豆生育后期叶绿素衰退,对叶片胞间CO2浓度影响不明显;随着施钼量的增加,各光合生理指标在C3(1.5 kg·hm-2)处理达到最高,然后开始下降;鲜食大豆叶片在R5(始粒)期各光合生理指标达到最高,R6(鼓粒)期开始下降,两品种对不同施钼水平处理的反应表现一致。     

富钼酿酒酵母菌株的选育及其生物学功能研究

以酿酒酵母单倍体菌株SY10作为出发菌株,采用紫外线、微波复合诱变处理其原生质体,选育出1株对钼高抗性突变株SY10-186-8,其抗性水平为400 mmol/L,是出发菌株的5.71倍。生物学功能结果表明,与出发菌株相比,该突变株拮抗紫外线、清除羟基自由基和超氧自由基能力以及黄嘌呤氧化酶活性均显著增强。经50世代培养,该突变菌株遗传稳定性良好,达90%以上。