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1.
减氮控磷稳钾施肥对水稻产量及养分积累的影响 总被引：26，自引：8，他引：18
氮、 磷用量偏大,钾肥用量不足不仅影响水稻的正常生长发育,而且导致养分利用率偏低。本文通过田间试验,研究减量施用氮、 磷肥,稳定钾肥投入对水稻产量、 养分积累量和肥料利用率的影响。试验设14个处理,每个处理重复2次。结果表明,氮钾、 磷钾、 氮磷钾配施处理的水稻秸秆生物量和籽粒产量均显著高于不施肥处理（P0.05）; 减氮控磷稳钾处理（N 225 kg/hm2、 P2O5 60 kg/hm2、 K2O 90 kg/hm2）与常规施肥处理相比（N 300 kg/hm2、 P2O5 150 kg/hm2、 K2O 60 kg/hm2）能显著增加水稻秸秆生物量（P0.05）,明显提高千粒重和籽粒产量; 试验还得出,减氮控磷稳钾处理分蘖期地上部氮、 钾含量和秸秆氮、 钾含量显著高于常规施肥处理（P0.05）; 收获期地上部氮、 钾的积累量和氮、 磷的表观利用率显著大于常规施肥处理（P0.05）。适当减少氮、 磷用量, 增加钾肥用量能改善氮、 钾营养状况,促进地上部干物质的积累,提高籽粒产量和氮、 磷表观利用率。N 196.2 kg/hm2、 P2O5 46.5 kg/hm2、 K2O 90 kg/hm2的配施方案具有实际推广应用价值。 相似文献
2.
不同氮素用量对杭白菊养分累积、转运及产量的影响 总被引：3，自引：2，他引：1
通过田间小区试验,研究不同施氮量对杭白菊养分积累、转运及产量的影响,以确定杭白菊最佳氮肥用量。试验设5个处理,氮素用量分别为0、90 kg/hm2、120 kg/hm2、150 kg/hm2、180 kg/hm2,以N0、N1、N2、N3、N4表示,5次重复。结果表明,不同氮素用量影响杭白菊不同时期干物质和养分的阶段积累量,但不影响其积累趋势,整个生育期内杭白菊氮、磷、钾积累量为钾氮磷。不同施氮量影响茎叶氮、磷、钾的转移效率和在不同器官中的分配比率,以不施肥处理最高,N3(150 kg/hm2)次之。在氮、磷、钾三种元素中,转运效率磷氮钾。收获期氮、磷、钾在不同器官的分配比率不同,氮素、钾素分配比率为茎花叶根,磷素分配比率为茎花根叶。各处理杭白菊花的产量在1746.232~211.3 kg/hm2之间,以N3(150 kg/hm2)处理产量最高。在本实验条件下,杭白菊的推荐施氮量为150 kg/hm2。 相似文献
3.
水稻季施肥对后季绿肥物质养分积累的影响 总被引：2，自引：0，他引：2
田间试验条件下,研究水稻季不同氮、磷、钾肥用量对后季绿肥物质养分积累的影响,为水稻-紫云英轮作条件下适宜化肥用量的确定提供依据。结果表明,水稻季施氮、磷、钾肥处理的绿肥鲜草产量分别较不施氮、磷、钾肥处理增加27.9% ~ 40.9%、12.6% ~ 37.2%、21.4% ~ 46.2%。水稻季不同氮肥处理比较,施氮处理的氮积累量较不施氮处理增加48.8% ~ 62.3%,氮肥（N）用量为142.4 kg/hm2时,绿肥碳、氮、钾积累量最高,氮肥用量为71.2 kg/hm2时,绿肥磷积累量最高。水稻季不同磷肥处理比较,施磷处理的绿肥磷积累量较不施磷处理增加33.0% ~ 78.3%,磷肥（P）用量为49.1 kg/hm2时绿肥的碳、氮、磷、钾积累量均最高。水稻季施钾处理的绿肥钾积累量较不施钾处理增加22.2% ~ 44.8%,水稻季钾肥（K）用量为67.5 kg/hm2和101.2 kg/hm2时,绿肥的碳、氮、磷、钾积累量较高,且两处理间相差较小。本试验条件下,水稻季氮、磷、钾用量分别为142.4、49.1、67.5（或101.2）kg/hm2时,绿肥的产量及碳、氮、磷、钾积累量最高,分别为15 833 kg/hm2和929.2、44.6、5.8、45.9 kg/hm2。 相似文献
4.
芝麻氮、磷、钾肥的效应研究 总被引：7，自引：1，他引：6
为探明芝麻生产中氮、磷、钾肥最优化施肥参数,本试验运用“3414”肥料效应田间试验方案,对白芝麻品种郑芝98N09和黑芝麻品种冀9014的氮、磷、钾肥料效应进行了研究.结果表明:适量氮、磷、钾用量及其配施能显著改善芝麻的经济性状,提高芝麻产量.施氮量与芝麻株高、单株蒴数、单蒴粒数、千粒重等经济性状呈显著正相关,氮、磷、钾肥对郑芝98N09的经济性状的影响为氮＞磷＞钾,冀9014为氮＞钾＞磷.通过建立肥料与产量效应函数方程并结合经济效益分析得出,郑芝98N09的最佳施肥量为N 123.09 kg/hm2、P2O5 60.13 kg/hm2、K2O 73.31 kg/hm2,冀9014的最佳施肥量为N 133.92 kg/hm2、P2O5 70.85 kg/hm2、K2O 110.80 kg/hm2.因此,郑芝98 N09施肥时应重施氮肥,适配磷、钾肥;冀9014应重施氮、钾肥,兼施磷肥. 相似文献
5.
不同施肥量对绿肥产量和养分积累的影响 总被引：5，自引：0，他引：5
大田试验条件下研究不同氮、磷、钾肥用量对绿肥[豆科绿肥紫云英(Astragalus sinicus L.)和禾本科绿肥看麦娘(Alopecurus aequalis Sobol.)]产量及养分积累量的影响。试验结果表明,施肥能显著增加绿肥产量,绿肥鲜草产量较不施肥处理增加42.8%~311.1%,与缺素处理相比,氮、磷、钾肥的增产率分别为57.1%~177.5%、27.8%~178.7%、14.2%~32.4%。两种绿肥的鲜草产量均随氮、磷、钾肥施用量的增加而增加,中、高水平的氮、磷肥用量下看麦娘的产量均高于紫云英,所有钾肥处理的看麦娘产量均高于紫云英。绿肥的养分积累量均随施肥量的增加而增加,中高水平的氮、磷肥用量下看麦娘的氮、磷积累量高于紫云英,不同钾水平下的看麦娘钾积累量均高于紫云英。氮、磷、钾肥用量分别为112.5 kg(N).hm?2、19.7 kg(P).hm?2、37.5 kg(K).hm?2时,两种绿肥总产量及碳、氮、磷、钾积累量最高,分别为49 424 kg.hm?2和3 212 kg(C).hm?2、151 kg(N).hm?2、19.8 kg(P).hm?2、156 kg(K).hm?2。此时看麦娘产量、碳、氮、磷、钾积累量分别占总量的59.0%、65.7%、66.3%和64.4%。紫云英田间自然洒种的看麦娘无成本投入且养分积累量高,不失为一种优质绿肥。 相似文献
6.
施钾水平对油茶养分积累和产油量的影响 总被引：3，自引：1，他引：2
【目的】油茶是中国南方主要的食用油料树种,油茶林地普遍极度缺钾。本文研究施钾水平对油茶氮、 磷、 钾养分积累和产油量的影响及它们之间的关系,从养分的角度分析钾素水平对油茶单株产油量的作用机理,为合理制定油茶林地土壤培肥制度提供科学依据。【方法】以7年生油茶无性系作为供试油茶品种,在江西九江进行田间试验。试验设置了6个K2O用量: 0、 100、 200、 300、 400、 500 kg/hm2和一个不施肥对照(CK),每个处理重复3次。调查和比较了不同处理油茶叶片和果实中氮、 磷、 钾养分含量及单株产油量差异,并针对叶片和果实养分对产油量的作用进行了通径分析。【结果】 K2O年施入量为300 kg/hm2时可有效促进油茶叶片6月份的磷、 钾及10月份叶片和果实的氮、 磷、 钾的积累,提高鲜果含油率和单株果实产量,单株产油量可达到430 g,增施钾肥对叶片6月份氮含量和种仁含油率的影响不明显。果实中的氮、 磷、 钾养分和叶片10月份的氮、 磷与单株产油量显著相关; 果实中的氮和磷积累量对油茶单株产油量的直接作用相对较大,10月份叶片中的氮对产油量也有一定的直接的影响,各养分对产油量的贡献大小顺序为: 果实磷果实氮果实钾叶片氮叶片磷。【结论】施钾水平影响油茶叶片和果实的养分积累,并进一步影响鲜果产量和产油量,K2O年施入量为300 kg/hm2是较适宜的用量。通过合理施用钾肥提高油茶10月份叶片氮、 磷和果实氮、 磷、 钾含量是获得油茶高产的有效途径。 相似文献
7.
施氮量对杂交棉氮、磷、钾吸收利用和产量及品质的影响 总被引：11，自引：2，他引：9
在高产条件下,研究了不同施氮量对杂交棉氮、磷、钾的吸收利用和产量及品质的影响。结果表明,增施氮肥显著提高了杂交棉氮、磷、钾的积累量,特别是显著提高了杂交棉后期氮、磷、钾的积累量和积累比例。施氮量N300 kg/hm2的子棉产量最高,比施氮量N 225 kg/hm2处理增产0.9%,但差异不显著。氮、磷、钾养分利用效率随施氮量增加而提高;但氮肥利用率随施氮量的增加而下降。施氮可以显著提高纤维长度和纤维比强度,而不同施氮量处理间纤维长度和比强度差别不大。 相似文献
8.
福建早稻测土配方施肥指标体系研究 总被引：13，自引：2，他引：13
根据近年来完成的135个氮、磷、钾肥效试验结果,建立福建早稻测土配方施肥指标体系。结果表明,土壤对稻谷的平均贡献率为73.5%,施用氮、磷、钾平均增产18.1%、5.4%和8.6%,土壤贡献率和氮、磷、钾增产效果与肥力等级成正比。山区早稻高产临界指标分别为碱解氮212 mg/kg、Olsen-P26 mg/kg和速效钾116 mg/kg,沿海早稻则分别为碱解氮203 mg/kg、Olsen-P 22 mg/kg和速效钾104 mg/kg,明显低于山区稻田。早稻最高施肥量平均为N166 kg/hm2、P2O569 kg/hm2和K2O 113 kg/hm2,经济施肥量平均为N 134 kg/hm2、P2O535 kg/hm2和K2O 78kg/hm2,但不同生产区域和土壤肥力等级的氮、磷、钾推荐用量有一定差异。建立了土测值与氮、磷、钾推荐用量的回归方程式,从而达到因土施肥的目的。 相似文献
9.
10.
施氮水平对甘蔗氮素吸收与利用的影响 总被引：1，自引：0，他引：1
以新台糖22号(ROC22)为试材,设15N标记尿素2.5、5.0和7.5g/盆(相当于225、450和675kg/hm2)3个处理,采用网室盆栽试验方式,研究施氮水平对甘蔗氮素吸收与利用的影响。结果表明:甘蔗吸收的氮素17.27%～27.28%来自施用的氮肥,72.72%～82.73%来自土壤和种茎;甘蔗氮肥利用率为34.21%～42.46%。随施氮水平提高,甘蔗干物质积累、氮素积累及来源于肥料氮素的比率显著增加,同时蔗叶对氮素的吸收利用呈上升趋势,但蔗茎对氮素的吸收利用呈下降趋势,氮肥利用率也显著下降。土壤碱解氮和硝态氮在各土层中的含量随施氮水平的提高而增加,且两者在0～20cm土层的积累明显大于20～40cm土层。本试验条件下,甘蔗氮肥施用为尿素5.0g/盆(相当于450kg/hm2)及土层深度为20cm较为适宜。 相似文献
11.
Friedman M 《Journal of agricultural and food chemistry》1999,47(4):1295-1319
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.
Barbosa J Freitas A Moura S Mourão JL Noronha da Silveira MI Ramos F 《Journal of agricultural and food chemistry》2011,59(22):11927-11934
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
13.
L. M. Mugwira 《Journal of plant nutrition》2013,36(5):591-606
This study was conducted to determine relationships between Al toxicity and mineral uptake of triticale (X Triticosecale, Wittmack), wheat (Triticum aestivum L.), and rye (Secale cereale L.). Two culti‐vars of each species were grown in 1/5‐strength Steinberg solution with 0, 3, 6, or 12 ppm Al added. The solutions were adjusted to pH 4.8 at transplanting and were not adjusted thereafter. The plants were grown in a growth chamber for 19 days before harvesting to determine nutrient solution pH, dry weights, and Al, Ca, Mg, K, and P levels in plants. Increasing Al concentration reduced the final pH of solutions. The addition of 12 ppm Al severely reduced the growth and increased Al concentration of plant tops. The Al levels in roots generally increased with increments of added Al up to 6 ppm. Increasing Al decreased the uptake of Ca, Mg, and P by plant tops more than that of K. Regression analyses indicated that Al toxicity was associated with increasing K/Ca + Mg equivalent ratios and decreasing P concentration in plant tops. Differences between species were: higher Al concentration in rye than wheat with 6 and 12 ppm Al, higher translocation of Ca from roots to tops in wheat than in rye and Mg in triticale and wheat than rye; K/Ca + Mg equivalent ratios associated with 50% reduction in top growth followed the order: triticales > tolerant wheat > sensitive wheat > rye. Differences in mineral uptake associated with Al toxicity in wheat were more indicative of differential Al sensitivity in wheat than in triticale and rye which have higher internal Al tolerance. 相似文献
14.
Christopher W Rogers Gongshe Hu Robert Mikkelsen 《Communications in Soil Science and Plant Analysis》2017,48(22):2678-2686
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
15.
《Communications in Soil Science and Plant Analysis》2012,43(9):751-756
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.
Sefton MA Skouroumounis GK Elsey GM Taylor DK 《Journal of agricultural and food chemistry》2011,59(18):9717-9746
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
17.
Rababah TM Hettiarachchy NS Horax R 《Journal of agricultural and food chemistry》2004,52(16):5183-5186
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
18.
《Communications in Soil Science and Plant Analysis》2012,43(9-10):1267-1277
Abstract Long‐term no‐tillage has profound effects on soil properties which can affect the availability of plant nutrient elements. The objectives were to study the effects of tillage and lime treatments on soil pH and extractable soil micronutrients where poultry litter was used as a nitrogen (N) source. Surface soil samples were taken in the spring and fall for two years from a long‐term tillage experiment that had been in place for nine years. There were two tillage treatments [conventional (CT) and no‐tillage (NT)] and six lime/ gypsum treatments (control, 8,960 kg gypsum ha‐1 every fourth year, 4,480 kg lime ha‐1 every fourth year, and three treatments of 8,960 kg lime ha‐1 in a four‐year period divided by application times into 1, 2, and 4 treatments per year). Poultry litter was applied each year of the two‐year experiment at a rate of 8.96 Mg ha‐1 on a dry weight basis. The crop was corn (Zea maize L.). Soil samples were analyzed for pH and Mehlich‐1 zinc (Zn), manganese (Mn), and copper (Cu). Soil pH was higher for NT than CT and was higher in the spring than in the fall. Lime rates resulted in soil pH increases, but showed less difference for CT than NT. The three 8,960 kg ha‐1 per four yr treatments caused an interaction in that for CT the pH increased more for 2,240 kg ha‐1each year than for 8,960 kg ha‐1 every fourth year and the opposite was true for NT. Extractable Zn, Mn, and Cu all responded to this interaction being lower for the higher pH plots. Extractable Zn was higher for NT possibly due to high Zn from the poultry litter and non‐incorporation for NT. Extractable Cu was lower for NT as expected from the soil pH, whereas extractable Mn was not affected by tillage. Extractable Zn and Cu both increased over time due to inputs from the poultry litter. Neither extractable Zn nor Mn responded to increasing lime rates, however Cu decreased with increasing lime rate. Extractable Cu was influenced mainly by soil pH differences due to tillage and lime. Extractable Zn was influenced much more by tillage and from inputs by the poultry litter and not as much by pH differences. Extractable Mn was the least responsive to tillage and lime treatments of the three micronutrients studied. 相似文献
19.
20.
《Communications in Soil Science and Plant Analysis》2012,43(9):741-750
Abstract The essential trace elements Fe, Mn, Zn, Cu, and B in high concentrations can produce phytotoxicities. Iron toxicity resulted from 5 × 10‐4 M and 10‐3 M FeSO4, but not from equivalent amounts of FeEDDHA (ferric ethylenediamine di (o‐hydroxyphenylacetic acid) ). Leaf concentrations in bush beans of 465 μg Mn/g, 291 μg B/g, and 321 μg Zn/g all on the dry weight basis resulted in 27%, 45%, and 34% reduction in yields of leaves, respectively. Zinc was concentrated in roots while Mn and B concentrated in leaves. Solution concentrations of MnS04 of 10‐3 and 10‐2 M depressed leaf yields of bush beans by 63% and 83%, respectively, with 5140 and 10780 μg Mn/g dry weight of leaves. Copper concentrations were simultaneously increased and those of Ca were decreased. Bush bean plants grown in Yolo loam soil with 200 μg Cu/g soil had a depression in leaf yield of 26% (with 28. 8 μg Cu/g leaf); plants failed to grow with 500 μg Cu/g soil. A level of 10‐3 M H2MoO4 was toxic to bush beans grown in solution culture. Leaves, stems, and roots, respectively, contained 710, and 1054, and 5920 μg Mo/g dry weight. 相似文献