饮用天然高钼水诱发的钼中毒耕牛主要生物酶测定

本研究对高钼饮水诱导钼中毒的耕牛及对照牛的血浆及组织（肝脏、肺脏、肾脏、脾脏、心脏、肌肉）中超氧化物歧化酶（ＳＯＤ）、黄嘌呤氧化酶（ＸＯＤ）及谷胱甘肽过氧化物酶（ＧＳＨ－ＰＸ）等３种生物酶活性进行了对比分析测定。结果表明,血浆和组织中ＳＯＤ、ＸＯＤ及ＧＳＨ－ＰＸ均随着钼中毒的加重其活性显著下降。这３种生物酶是钼中毒比较灵敏且相关较大的生化指标,对钼中毒具有一定诊断价值;测定ＳＯＤ。ＸＯＤ、ＧＳＨ－ＰＸ可作为钼中毒监测的重要手段。     

钼胁迫对烟草光合荧光参数和叶绿体超微结构的影响

为探明烟草响应钼胁迫光合生理机制,研究了缺钼胁迫对烟草光合气体交换、叶绿素荧光参数和叶绿体超微结构的影响。结果表明:缺钼培养10 d后,烟苗光合色素含量和净光合速率较对照有所降低,胞间二氧化碳浓度、气孔导度和蒸腾速率提高,光系统初始荧光和非光化学猝灭系数提高,光合电子传递速率和最大光化学效率降低,但差异均不显著;烟苗的叶绿体基类片层和基质片层排列松散,淀粉粒数量少。培养20 d时,缺钼和对照烟苗的多数指标差异显著。培养30 d时,除蒸腾速率外,缺钼和对照烟苗的其它指标差异均显著,叶绿体片层结构受损严重,淀粉粒发育差。缺钼胁迫损伤了叶绿体超微结构,抑制了原初光能转化效率,降低了光合能力。且随胁迫时间延长,缺素表现明显。     

钼的毒性与反刍动物钼中毒

本文综述了微量元素钼对反刍动物毒性的研究结果,如:钼的化学特性、钼在饲料与反刍动物体内的含量与分布、钼的生物学作用、钼在反刍动物体内的吸收、代谢及与其它元素间的互作等。最后阐述了反刍动物钼营养需要量、饲料中钼的最大允许量及反刍动物钼中毒的防治。     

土壤中痕量钼的催化光度测定法

本文研究了钼(Ⅳ)在 HCl—KCl 缓冲液介质中催化过氧化氢氧化对氨基乙酰苯胺和β—萘酚的显色反应。并拟定了催化分光光度测定土壤中痕量钼的新方法,本方法的灵敏度为8×10~(-10)g/ml,测定范围0～1.0μg/25ml,本法已用于土壤中痕量钼的测定。     

Determination of molybdenum in plant tissue by graphite furnace atomic absorption spectrophotometry (GFAAS)

Abstract

The analysis of molybdenum in plant tissue using graphite furnace atomic absorption spectrophotometry (GFAAS) is described. The method involved wet digestion using a mixture of sulphuric, nitric and perchloric acids followed by a solvent extraction procedure. Molybdenum was extracted into di‐iso butyl ketone (DIBK) as the iron‐thiocyanate complex. The extract was then analysed for molybdenum by GFAAS.

The results of analyses of the reference plant materials (orchard leaves and citrus leaves) of the National Bureau of Standards (NBS) compared very well with the certified values. Other types of plant tissue were also analysed and the results correlated well with those obtained by an alternative method.     

Molybdenum reserves of seed,and growth and N2 fixation by Phaseolus vulgaris L.

Summary Plants grown from seed with high (1.5–7.3 g Mo seed^-1) and low (0.07–1.4 g Mo seed^-1) Mo contents were grown in the presence and absence of Mo in growth media (perlite) or in a flowing-solution culture, in a controlled environment. Neither the high (1.5 g Mo seed^-1) nor the low (0.1 g Mo seed^-1) Mo content in seed from a small-seeded genotype (BAT 1297) was able to prevent Mo deficiency (reduced shoot, root and nodule dry weight, N₂ fixation and seed production) in growth media without an external supply of Mo, whereas both the high (7.3 g Mo seed^-1) and the low (0.07 g Mo seed^-1) contents in seed were able to prevent Mo deficiency in a large-seeded genotype (Canadian Wonder). Responses to Mo treatment by the Two genotypes were inconsistent between the growth media and solution culture experiments. Seed with a large Mo content (3.5 g Mo seed^-1) from the Canadian Wonder genotype was unable to prevent Mo deficiency (reduced shoot and nodule dry weight and N₂-fixation) in a solution culture without an external source of Mo, whereas both the large (1.7 g Mo seed^-1) and the small (0.13 g Mo seed^-1) contents in seed prevented a deficiency in BAT 1297. Growing plants from seed with a small Mo content, without additional Mo, reduced the seed Mo content by 83–85% and seed production by up to 38% in both genotypes. Changes in seed size and increases in shoot, root and nodule dry weight occurred, but varied with the genotype and growth conditions. These effects were also observed in some cases where plants were grown with additional Mo, demonstrating that the amount of Mo in the seed sown can influence plant nutrition irrespective of the external Mo supply. Nodule dry weight, total N content of shoots and seed production were improved by using seed with a small Mo content (1.64–3.57 g Mo seed^-1) on acid tropical soils in Northern Zambia. Plants of both the large- and small-seeded genotypes grown from seed with a small Mo content (<1.41 g Mo seed^-1) had a smaller nodule weight, accumulated less N and produced less seed. The viability of seed with a small Mo content was lower (germination up to 50% less) than that of seed with a large Mo content.     

钼硒配施对小白菜钼硒形态及硒价态的影响

通过盆栽试验研究钼硒配施对水培小白菜钼硒形态及硒价态的影响。结果表明:施硒增加了小白菜地上部及地下部醇溶态和水溶态钼含量,降低了小白菜地上部及地下部盐溶态及醋酸溶态钼的含量,增加了地下部盐酸溶态钼含量,对地上部盐酸溶态钼含量没有太大的影响。施钼对小白菜地上部醇溶态、水溶态硒含量影响不大,增加了盐溶态及盐酸溶态硒的含量,降低了醋酸溶态硒的含量;施钼对小白菜地下部醇溶态硒含量影响不大,降低了水溶态硒的含量,增加了盐溶态、醋酸溶态及盐酸溶态硒的含量。施用四价的亚硒酸钠对小白菜可食部位硒的有机化较为有利,并且施钼也能促进高硒水平下小白菜体内硒的有机化。因此,钼硒配施虽然对小白菜体内钼和硒的各赋存形态有拮抗作用也有协同作用,但是有利于生产富含有机硒的作物。     

植物种子中微量钼的电化学发光分析法测定研究

[目的]对测定植物种子中微量钼的电化学发光分析法进行研究。[方法]试验所用的仪器由一个电生试剂系统和一个流动注射化学发光检测系统组成,筛选仪器运行所需的最佳电解电位、试液酸度、鲁米诺的浓度和碱度、试液流速,并在此基础上对种子样品中的钼含量进行分析。[结果]在-0.60 V(vs:Ag/AgCl)下恒电位电解还原钼(VI)为钼(III),钼(III)与鲁米诺在碱性条件下产生化学发光,发光强度与钼(VI)的浓度呈线性正相关,从而建立了钼的流动注射电化学发光分析法。该方法的线性范围为5.0×10-10～5.0×10-7g/ml,检出限为5×10-11 g/ml钼(VI),对1.0×10-9 g/ml钼(VI)进行11次测定,得到相对标准偏差为2.6%。将该方法用于植物种子中微量钼的测定,效果较好。[结论]该方法与以前测定钼的化学发光分析法相比,不仅提高了方法的灵敏度,而且在一定程度上提高了方法的选择性,且避免了有毒试剂汞的使用。     

大豆钼素研究

本文报导了我国黄淮及长江中下游大豆产区土壤有效钼低于０．１５ｐｐｍ的点次达９８％，在缺钼条件下，钼主要分布于大豆根和叶，不缺钼则主要存在于根和茎中，后期钼主要贮于种子中；大豆有富集钼功能；缺钼大豆的光合作用和固氮酶性降低。硝酸还原酶活性及叶绿素含量，在水培介质为０．０５－０．１ｐｐｍ范围内，与钼浓度正相关，大豆各器官及全株干重变化亦有类似趋势，施钼提高了除胱氨酸和异亮氨酸外的其它１５种氨基酸含量，     

配施硼肥·钼肥对花生产量的影响

[目的]为了探讨硼肥、钼肥及施肥方法对花生产量的影响。[方法]以赣花8号为材料,在等量复合肥作为底肥施用的条件下,设硼肥、钼肥作为底肥施用和作为叶面肥喷施等7个处理,研究复合肥配施硼肥、锌肥对花生产量的影响。[结果]硼肥、钼肥主要通过增加花生的双仁果数、饱果数、百果重等增加产量;硼肥、钼肥作为叶面肥喷施的增产效果比作为底肥施用的效果好。无论是作为底肥施用还是作为叶面肥喷施,硼肥、钼肥混合施用的效果都比单独施用的增产效果好。[结论]在生产上,最好将硼肥、钼肥作为叶面肥混合喷施。