钼、硼对大豆光合效率的影响

以大豆(Glycinemax)浙春3号、浙春2号和3811等3个品种为材料,设置了不同的钼、硼处理(低钼低硼,施钼,施硼和钼、硼同施),研究了钼、硼对大豆光合效率的影响。结果表明,施钼或硼促进了大豆叶面积的扩大,提高了大豆光合速率和荚的可溶性糖含量,延缓了大豆生育后期叶绿素的衰退,增强大豆的呼吸作用,降低茎和叶的可溶性糖含量,从而提高了大豆的光合效率,且钼、硼同施作用更大。在对大豆光合叶面积、叶绿素含量和呼吸作用的影响强度上,钼的作用于大硼;对大豆光合速率和可溶性糖含量的影响强度,硼的作用大于钼。3个大豆品种对钼、硼的反应存在一定的基因型差异。     

钼胁迫对烟草含钼酶和碳氮代谢关键酶的影响

为了解缺钼对烟草含钼酶和碳氮代谢过程的影响,以南江3号烤烟品种为材料,采用营养液培养,设置施钼(含钼0.20mg·kg-1全营养液)和缺钼(去钼全营养液)2个处理,研究缺钼对烟草发育过程中的含钼酶、碳氮代谢关键酶及其相关代谢产物的影响。结果表明,培养10d时,缺钼处理下,烟草的含钼酶和碳氮代谢关键酶(黄嘌呤脱氢酶、硝酸还原酶、谷氨酰胺合成酶、淀粉酶、磷酸蔗糖合成酶和转化酶)比0d时高,但与施钼处理烟草之间差异不显著;缺钼处理的烟草亚硝酸盐含量显著高于施钼处理烟草。培养20d时,除磷酸蔗糖合成酶的活性提高外,缺钼处理的烟草含钼酶和氮代谢关键酶含量或活性大多显著下降,蔗糖和蛋白质含量均低于施钼处理烟草,亚硝酸盐含量显著高于施钼处理烟草。培养30d时,缺钼处理烟草含钼酶和碳、氮代谢相关酶含量或活性均下降,且显著低于施钼处理烟草;施钼处理烟草则稳中有升,且2个处理烟草的蛋白质和亚硝酸盐含量差异显著。可知,缺钼显著降低烟草中含钼酶和碳氮代谢关键酶活性或含量,抑制了氮代谢,加快了氮代谢向碳代谢的提前转换,使叶片提前落黄。本研究为协调烟草中碳氮代谢提供了准确的生理生化信息。     

钼、锰营养对大豆碳氮代谢的影响

钼、锰是植物生长所必需的微量元素,对作物的生长发育、产量和品质都有明显影响。钼在植物氮代谢中起着关键作用,主要与钼是硝酸还原酶和固氮酶等含钼酶类的重要组成成分有关[1]。同时钼对维持叶绿体的正常结构也是必不可少的,缺钼会导致植物叶绿素含量减少,光合强度降低[2]。锰对作物的光合作用、氮、碳和脂类代谢有密切关系,并是多种酶的组分与活化剂,锰营养的丰缺对大豆的生长发育、产量及抗逆性有显著影响[3]。在钼或锰营养方面,目前研究较多是钼或锰对大豆的产量、品质和生理活性的影响,例如施钼能提高豆科植物根瘤菌数量,促进植株生长,增加生物量和产量[4~6]。锰浸种会影响大豆种子萌发和幼苗的生理特性[7],施锰     

硼对大豆结瘤和固氮作用的影响——Ⅰ.对生长、营养元素吸收与分布和固氮量影响

在短期无氮营养液栽培(28天)条件下,研究缺硼和正常供硼处理对Bragg大豆品种及不结瘤突变体nod49和超结瘤突变体nts382生长、矿质元素吸收与分布及固氮量的影响。试验结果表明:1.在正常供硼的条件下,不结瘤突变体nod的植株生长量,株高、主根生长均高于超结瘤突变体及其亲本。缺硼处理时三种基因型大豆的生长均受到明显的抑制作用。无论是正常供硼还是缺硼处理,超结瘤突变体nts382根系的生长量均明显小于其它基因型。2.正常供硼处理时三种基因型大豆地上部、根及nts382的根瘤中硼的浓度和积累量均高于缺硼处理。缺硼处理,超结瘤突变体及其亲本地上部和根中大部分矿质元素浓度高于正常供硼处理,但积累总量低于正常供硼处理或变化不大。施硼处理的nts382和Bragg,根和根瘤中钙的浓度和积累量明显降低,而地上部变化不大,同时在nts382根瘤中,锌、锰、铁、铜浓度和含量也下降,而钼含量增加。3.施硼处理和Bragg和nts382地上部、根及根瘤中氮的浓度和含量均显著高于缺硼处理,其中超结瘤突变体中氮浓度和总量最高。在缺硼条件下,Bragg和超结瘤突变体能够结瘤,但是Bragg大豆根瘤的固氮作用完全受到抑制,而nts382根瘤还能保持较强的固氮能力。     

硼对大豆结瘤和固氮作用的影响——Ⅰ.对生长、营养元素吸收与分布和固氮量影响

在短期无氮营养液栽培(28天)条件下,研究缺硼和正常供硼处理对Bragg大豆品种及不结瘤突变体nod49和超结瘤突变体nts382生长、矿质元素吸收与分布及固氮量的影响。试验结果表明:1.在正常供硼的条件下,不结瘤突变体nod的植株生长量,株高、主根生长均高于超结瘤突变体及其亲本。缺硼处理时三种基因型大豆的生长均受到明显的抑制作用。无论是正常供硼还是缺硼处理,超结瘤突变体nts382根系的生长量均明显小于其它基因型。2.正常供硼处理时三种基因型大豆地上部、根及nts382的根瘤中硼的浓度和积累量均高于缺硼处理。缺硼处理,超结瘤突变体及其亲本地上部和根中大部分矿质元素浓度高于正常供硼处理,但积累总量低于正常供硼处理或变化不大。施硼处理的nts382和Bragg,根和根瘤中钙的浓度和积累量明显降低,而地上部变化不大,同时在nts382根瘤中,锌、锰、铁、铜浓度和含量也下降,而钼含量增加。3.施硼处理和Bragg和nts382地上部、根及根瘤中氮的浓度和含量均显著高于缺硼处理,其中超结瘤突变体中氮浓度和总量最高。在缺硼条件下,Bragg和超结瘤突变体能够结瘤,但是Bragg大豆根瘤的固氮作用完全受到抑制,而nts382根瘤还能保持较强的固氮能力。     

硼对烤烟硼、钾积累及碳氮代谢的影响

采用砂培法研究不同硼浓度处理对烤烟碳氮代谢的影响.结果表明,低浓度硼(5 μmol/LH3BO3)处理下,烟株各器官中的硼、氮、钾、干物质积累以及NO3-的吸收及同化受阻,叶片中的NH4 积累增加,而氨基酸和蛋白质含量降低;缺硼还降低烟株叶片的光合速率,并使叶片中的水溶性葡萄糖、果糖、蔗糖、淀粉大量积累.增加硼的供给(20/μmol/L和40 μmol/L),使烟株叶片碳氮代谢增强.植株各器官的氮、钾、硼含量增加,干物质积累增强.     

在石灰性土上锌、硼营养对大豆品质及产量的影响

石灰性潮泥土中,锌、硼的有效性很低,在这类土上种植大豆,常出现“花而不实”症。本试验在施以适量氮、磷、钾肥的基础上,增施锌肥和硼肥,大豆产量均比对照增产达显著水平。锌、硼能促进大豆植株对氮、钾的吸收,锌、硼之间也有互相促进吸收的作用。锌、硼能加强大豆体内的新陈代谢,防止早衰,增加分枝,提高结实率和蛋白质含量。     

低温对缺钼冬小麦幼苗生长的影响 II.对氮代谢的影响

对三叶一心的缺钼冬小麦进行 24h低温处理 (-5～0℃) ,了解其对氮代谢诸方面的影响。结果显示 ,缺钼对植株全氮含量基本无影响 ,但能明显影响氮在植株各部位的分配。常温下 ,供钼显著降低植株地上部全氮含量 ,但根部全氮量明显增加 ;低温条件下 ,供钼与不施钼处理的冬小麦根部全氮量无大差别 ;无论温度如何 ,施钼与否 ,各处理地上部、根中可溶性蛋白含量均无显著差别。常温下 ,施钼显著提高地上部游离氨基酸含量 ,低温处理后 ,施钼和缺钼处理的植株地上部游离氨基酸含量均明显提高 ,且施钼处理显著高于缺钼处理。通过对硝酸还原酶活性的测定证实 ,常温下 ,钼对冬小麦体内硝酸还原酶活性无影响 ;在低温条件下 ,缺钼植株地上部、根中硝酸还原酶活性明显低于施钼植株 ,施钼植株硝酸还原酶活性能保持在较高水平。     

施用硼、锌、钼肥对紫花苜蓿生长及品质的影响

试验阐明了在京郊土壤条件下施用硼、锌、钼肥对紫花苜蓿生长、品质和营养吸收的影响,为苜蓿的合理施肥提供了依据。结果表明:施用硼、锌和钼肥能够不同程度地提高苜蓿株丛数、改善结瘤、促进分枝、增加株高。微肥对产量的影响因土壤而异,当土壤有效锌、硼、钼含量分别低于1.8mg/kg、0.5mg/kg及0.1mg/kg时,施用微肥的增产效果明显。适当施用硼、锌、钼肥能够提高苜蓿粗蛋白质含量。苜蓿的吸氮量受硼、锌、钼肥影响显著,其中硼肥的作用最大,苜蓿的吸磷量受锌、钼的影响显著,吸钾量受硼、钼的影响显著。     

罗平烟区土壤有效硼、钼含量与烟叶硼、钼含量的关系分析

以罗平县植烟土壤为研究对象,分析了罗平县土壤有效硼、有效钼含量及其互作与烟叶硼、钼含量的关系。结果表明:(1)罗平县土壤有效硼含量平均值为0.540 mg/kg,变幅为0.051~3.033 mg/kg,变异系数为77.78%;土壤有效钼含量丰富,平均值为0.489 mg/kg,变幅为0~3.458 mg/kg,变异系数高达98.77%。(2)罗平县烟叶硼含量平均值为16.301 mg/kg,变幅为2.163~35.684 mg/kg,符合优质烤烟硼含量范围内的样本数占总数的88.89%;烟叶钼含量偏低,平均值为0.535 mg/kg,变幅为0.059~4.059 mg/kg,符合优质烟叶生长发育钼含量的样本数占总样本数的48.83%。(3)烟叶硼含量与土壤有效硼含量呈极显著正相关,相关系数为0.215,烟叶硼含量(y^)与土壤有效硼含量(x)的回归方程为y^=14.720+2.925x;烟叶钼含量与土壤有效钼含量呈极显著正相关,相关系数为0.411,烟叶钼含量(y^)与土壤有效钼含量(x)的回归方程为y^=0.335+0.409x;(4)土壤有效硼和有效钼的交互作用对烟叶硼含量存在极显著影响,但对烟叶钼含量的影响未达到显著水平。     

Difference in system of current photosynthesized carbon distribution to carbon and nitrogen compounds between rice and soybean

¹⁴CO₂ was assimilated during 10 min in leaf of rice and soybean under 21 kPa O2 (21% O₂ treatment) and 2 kPa O₂ (2% O₂ treatment) at the vegetative growth stage and flowering stage. The ¹⁴C distribution ratio to respired CO₂ and crude chemical components (sugars, polysaccharides, amino acids, organic acids, and proteins) was determined. In this paper, since emphasis was placed on the ¹⁴C distribution mechanism to carbon compounds and nitrogen compounds, the terms carbon metabolism pool (C-pool) composed of sugars and polysaccharides, and nitrogen metabolism pool (N-pool) composed of organic acids, amino acids and proteins were used. The results obtained were as follows.

¹⁴C distribution ratio to N-pool at 0 min after ¹⁴C assimilation was higher in soybean than in rice regardless of the treatments and stages, and that at 30 min after ¹⁴C assimilation under light condition markedly decreased both in rice and soybean. Therefore, especially in soybean, a large amount of photosynthesized ¹⁴C was once distributed to the N-pool, then ¹⁴C compounds in the N-pool were reconstructed into the C-pool. During this reconstruction process, ¹⁴C compounds in the N-pool were actively respired.

¹⁴C distribution to N-pool at 0 min after ¹⁴C assimilation changed slightly or did not change by the N treatment. ¹⁴C distribution to N-pool in the - N treatment of soybean (13–29 mg N g^-1 content in leaves) was higher than that in the + N treatment of rice (31–48 mg N g^-1 content in leaves). Photosynthesized carbon distribution to N-pool in rice decreased with growth, while it remained constant in soybean. Accordingly, in soybean, photosynthesized carbon was predominantly distributed to the N-pool through photorespiration and/or Calvin cycle (supplying triose-P), which was less affected by nitrogen nutrient and aging. Thus, the mechanism of photosynthesized carbon distribution to carbon and nitrogen compounds was basically regulated by inherited characters of each plant more than by the nitrogen status of leaves.

By the 2% O₂ treatment, ¹⁴C distribution to N-pool decreased in both crops regardless of N treatment, indicating that photorespiration plays an important role in the supply of the preliminarily photosynthesized carbon compounds to N-pool. In the 2% O₂ treatment, ¹⁴C distribution to N-pool was higher in soybean than in rice, indicating that triose-P transported from chloroplast was preferentially distributed to N-pool in the case of soybean.     

铁和不同形态氮素对玉米植株吸收矿质元素及其在体内分布的影响——Ⅰ.对氮、磷、钾、钙、镁等营养元素的影响

用营养液培养方法研究了铁和两种形态氮素(NO₃^--N和NH₄⁺-N)对玉米植株吸收氮、磷、钾等大量元素和钙、镁等中量元素及其在体内分布的影响。结果表明:与NO₃^--N相比,供应NH₄⁺-N促进了玉米对氮的吸收,在缺铁条件下,降低了对磷、钾、钙及镁的吸收。铁和NH₄⁺-N都显著提高了玉米植株各器官中氮的含量。与NH₄⁺-N处理相比,NO₃^--N处理的新叶中磷含量显著增加,但铁的供应对植物体内磷的含量无显著影响。使用NO₃^--N显著提高了玉米新叶和老叶中钾的含量,根和茎中钾的含量无明显影响。铁的供应降低了新叶和老叶中钾的含量。供铁时,NH₄⁺-N处理的玉米新叶中钙和镁的含量显著低于NO₃^--N处理,而在缺铁时则无显著差异。     

Elevated CO2 concentrations increase leaf nitrate reduction by strengthening sink activity in soybean plants

An experiment was conducted to examine the effect of CO₂ enrichment on the nitrate uptake, nitrate reduction activity, and translocation of assimilated-N from leaves at varying levels of nitrogen nutrition in soybean using ¹⁵N tracer technique. CO₂ enrichment significantly increased the plant biomass, apparent leaf photosynthesis, sugar and starch contents of leaves, and reduced-N contents of the plant organs only when the plants were grown at high levels of nitrogen. A high supply of nitrogen enhanced plant growth and increased the reduced-N content of the plant organs, but its effect on the carbohydrate contents and photosynthetic rate were not significant. However, the combination of high CO₂ and high nitrogen levels led to an additive effect on all these parameters. The nitrate reductase activity increased temporarily for a short period of time by CO₂ enrichment and high nitrogen levels. ¹⁵N tracer studies indicated that the increase in the amount of reduced-N by CO₂ enrichment was derived from nitrate-N and not from fixed-N of the plant. To examine the translocation of reduced-N from the leaf in more detail, another experiment was conducted by feeding the plants with ¹⁵NO₃-N through a terminal leaflet of an upper trifoliated leaf under depodding and/or CO₂ enrichment conditions. The export rate of ¹⁵N from the terminal leaflet to other plant parts decreased by depodding, but it increased by CO₂ enrichment. CO₂ enrichment increased the percentage of plant ¹⁵N in the stem and / or pods. Depodding increased the percentage of plant ¹⁵N in the leaf and stem. The results suggested that the increase in the leaf nitrate reduction activity by CO₂ enrichment was due to the increase of the translocation of reduced-N from leaves through the strengthening of the sink activity of pods and / or stem for reduced-N.     

铁和不同形态氮素对玉米植株吸收矿质元素及其在体内分布的影响 Ⅱ.对铁、锰、铜、锌等营养元素的影响

用营养液培养方法研究了铁和两种形态氮素对玉米植株吸收铁、锰、铜、锌等微量元素及其在体内分布的影响。结果表明:与硝态氮(NO₃^--N)相比,铵态氮(NH₄⁺-N)显著提高了玉米对铁的吸收,降低了对锰、铜及锌的吸收。供铁也明显提高了植株地上部铁的吸收总量,降低了锰及锌的吸收量,尤其是在供应No₃^--N时这种作用更为明显。在缺铁条件下,NH₄⁺-N处理的玉米新叶中铁的含量明显高于NO₃^--N处理;而新叶、老叶、茎中锰、锌、铜含量以及根中锰、锌含量都明显低于NO₃^--N处理。但使用NH₄⁺-N时,根中铜的含量较高。在供铁条件下,NH₄⁺-N处理的玉米植株四个不同器官中锰和锌的含量显著低于NO₃^--N处理的植株,而铜的含量正好相反。在缺铁条件下,玉米新叶中活性锰、活性锌的含量显著高于供铁处理;与NO₃^--N相比,NH₄⁺-N的供应也显著降低了玉米新叶中活性锰以及活性锌的含量。     

Absorption of various types of chelated copper in a low concentration range by cucumber

Two experiments were conducted to compare absorption of copper (Cu) from cupric chloride (CuCl₂) and various types of chelated Cu in a low concentration range by cucumbers. In the first experiment, two varieties of cucumber were grown on rockwool for 40 days in a glasshouse with standard nutrient solution which contained six different concentrations of CuCl₂ (0, 0.05, 0.10, 0.20, 0.40, and 0.80 μmol/L). Copper deficiency symptoms were examined during the growing period, and the total nitrogen (N), iron (Fe), manganese (Mn), zinc (Zn), and copper contents of young fully grown leaves were measured. There were no differences among treatments in the leaf contents of N and Mn. Copper contents increased and Zn decreased with increasing Cu levels. The content of Cu at the three low Cu treatments (including no Cu addition) were in the deficient range (48–65 μmol/kg dry matter). The zero Cu level had paler green leaves than other treatments. No differences were apparent between varieties. The second experiment was carried out under exactly the same conditions as the first, but on the basis of the results of the first experiment, Cu treatments were 0, Cu‐EDDHA at 0.4, Cu‐DTPA at 0.4, Cu‐EDTA at 0.4, Cu‐NTA at 0.4, CuCl₂ at 0.4 μmo/L as Cu²⁺. After the experiment, the total N, Fe, Mn, Zn, and Cu contents of young, fully grown leaves were measured. There were no differences between treatments in the leaf contents of Cu except zero Cu level. They were in the range of 101–119 μmol/kg dry matter. At no Cu addition treatment, the Cu content was only 31 μmol/kg dry matter which is considered to be the deficiency level. For the other examined elements, there were no differences among the treatments and varieties. From these data it was concluded that the availability of these chelated Cu types were the same as CuCl₂ under the conditions of the experiments conducted.     

Responses of Root Growth and Nitrogen Transfer Metabolism to Uniconazole,a Growth Retardant,during the Seedling Stage of Soybean under Relay Strip Intercropping System

Relay strip intercropping of soybean has been widely developed in the southwest of China to secure China's soybean production. However, due to the shading from maize, soybean plants are thin and have a poor root system. Uniconazole is a plant-growth retardant that could enhance root vigor; increase root length, root volume, and root dry weight; and affect nitrogen (N) metabolism. To understand the effects of uniconazole on the root growth and N-transfer metabolism of soybean seedlings under relay strip intercropping, the changes in some morphological characteristics of root, dry-matter weight, root vigor, nitrate (NO₃ ^?)-N, ammonium (NH₄ ⁺)-N, and amino acid of xylem sap after seed treatment with uniconazole powder (0, 2, 4, and 8 mg kg^?1 seed) were investigated. Main root length, total lateral root lengths, first lateral root numbers, root nodule numbers, root vigor together with bleeding sap, bleeding sap–top ratio, root dry weight, and root/shoot ratio were increased, indicating uniconazole improved soybean root system in relay strip intercropping. Uniconazole powder treatment could increase NO₃ ^?-N, NH₄ ⁺-N, and total amino acid of xylem sap, to increase the potential of leaf and root N reduction and assimilation, and increase of leaf and root N contents. Thus, results suggested that uniconazole treatment can improve root growth and N transfer mechanism of soybean to support its further growth.     

EFFECTS OF NITROGEN FERTILIZATION ON THE BIOCHEMICAL AND PHYSIOLOGICAL PARAMETERS IN LEAVES AND ROOT OF SUGAR BEET ASSOCIATED WITH AZOTOBACTER CHROOCOCCUM

A field experiment was conducted to investigate the effect of nitrogen (N) application on the growth and metabolism of sugar beet (Beta vulgaris L.). Changes in nitrate, ammonium, soluble protein and pigment levels, nitrogen metabolism enzyme activity, biomass of leaves and beet, and sucrose and α-amino-N were studied in relation to five different NPK application rates (0, 50, 100, 150, and 200 kg N ha^?1) and association with Azotobacter chrooccocum. The availability of nitrate and ammonium ions in the leaves proved to be influenced by the different nitrogen treatments. The most important enzymatic activities within nitrogen metabolism were affected negatively by the highest NPK rate. With increasing nitrogen supply, the concentration of α-amino-N increased considerably and that of sucrose decreased. Application of NPK had a significant positive effect on the growth and biomass production. The measured parameters of plants associated with A. chrooccocum were of similar magnitude comparing to the controls.     

四川地区玉米/大豆带状套作对大豆形态、叶绿素荧光特征及系统产量的影响

玉米/大豆带状套作可以充分利用光环境,提高单位土地面积物质产出。为探明玉米/大豆带状复合种植模式下不同空间配置对大豆冠层光环境、形态、产量及系统效益的影响,进而为大豆高产优质栽培提供依据,本研究选用半紧凑型（‘川单418’）和紧凑型（‘荣玉1210’）玉米品种与大豆带状套作,固定带宽为200 cm,玉米采用宽窄行种植,玉米窄行距设置3个处理：20 cm、40 cm、60 cm;并以单作大豆（SS）作为对照。分析透光率、形态、光合色素、荧光参数、生物量和系统产量的变化规律。结果表明：套作大豆冠层透光率、红光/远红光（R/FR）比值随玉米窄行距的增大而逐渐降低;套作下大豆茎粗、节数、茎干重和全叶干重均随玉米窄行距增大呈降低趋势,最大值出现在玉米窄行距20 cm处理下;与单作大豆相比,两个玉米品种下大豆茎粗、节数、茎干重和全叶干重均显著降低,而第2节间长和主茎长显著升高。套作下大豆叶片光合色素含量随玉米窄行距的增大而逐渐降低,各行距处理及不同玉米品种下套作的叶片光合色素含量均低于单作大豆。大豆叶片荧光参数F_v/F_m、NPQ、F_q''F_m''和F_q''/F_v''随玉米窄行距的增大均呈先增大后减小的趋势,而F_o变化趋势与之相反。玉米收获后,大豆光环境得到改善并迅速恢复生长,套作大豆形态生理指标与单作差异减小,但由于前期玉米的遮荫,各套作处理间大豆产量差异仍显著。通过系统效益分析,在玉米窄行距40 cm处理下,套作系统综合产量最高,两玉米品种下玉米、大豆产量平均分别为8 559.52 kg·hm^-2、1 717.60 kg·hm^-2,土地当量比平均达1.57。本试验中大豆与两个株型玉米套作,大豆形态生理指标差异影响不显著。因此,选择紧凑或半紧凑玉米品种,适度缩小玉米窄行距可以显著改善带状套作大豆的生长环境,提高其生物量和产量。