Zinc response in pigeon pea as influenced by genotypic variability

Seven improved cultivars of pigeon pea (Cajanus cajan (L.) Mill sp.) were evaluated at 0 (original Zn deficient soil), 5 and 50 ppm Zn levels under greenhouse conditions. Plants were harvested at 6 weeks after sowing and at maturity. Responses to 5 ppm Zn in shoot at 6 weeks of growth, and in leaf, stem, pod-hull and grain at maturity ranged from 63 to 387, 37 to 116, 15 to 73,9 to 145 and 51 to 200%, respectively. Application of 50 ppm Zn in most of the cultivars did not markedly affect the yield of different plant parts. Zinc concentration at 0 Zn level in shoot at 6 weeks of growth and in leaf, stem, pod-hull and grain of different genotypes varied from 9.8 to 14.5, 13.7 to 21.2, 10.8 to 16.7, 4.17 to 5.83 and 9.2 to 16.7 ppm, respectively, and the increase in concentration with 5 ppm applied Zn ranged from 28 to 248, 28 to 89, 27 to 85, 20 to 142, and 105 to 254 per cent, respectively. The concentration further increased with an increase in Zn level to 50 ppm. There was less variation in the yield and tissue Zn concentration of different genotypes after Zn application. Phosphorus concentration at 0 Zn level in shoot at 6 weeks of growth, and in leaf, stem, pod-hull and grain of different genotypes varied from 0.50 to 0.71, 0.18 to 0.31, 0.11 to 0.24, 0.15 to 0.20 and 0.43 to 0.58% respectively. Zinc decreased P in all plant parts but relative decrease was more in vegetative parts than in grain. The variability in Zn response among pigeon pea genotypes could partly be attributed to the maintenance of proper P/Zn balance in metabolically active plant parts, such as, leaf, and partly to their capacity to exploit soil Zn and to translocate it to the above-ground parts.Contribution from the Department of Soils, Haryana Agricultural University, Hissar (India).     

Tolerance of wheat and pea to boron in irrigation water

In a micro-plot experiment 1.5 ppm boron in the irrigation water was toxic for wheat. Its concentration in the soil solution increased to 1.53 ppm and in the plant tissue to 58 ppm. In pea plants 4 ppm B in the irrigation water was toxic with 2.00 ppm soil solution B and 213 ppm tissue B. Nitrogen in both species increased significantly and calcium decreased with the increase in B in irrigation water. The yield of wheat grain declined by 13, 20 and 32 per cent at the 4.0, 6.0 and 8.0 ppm B respectively. The yield of straw and grains of pea declined by 31, 56 and 41, 56 per cent at 6.0 and 8.0 ppm B levels respectively. Thus tolerance to B in irrigation water was between 3.0 and 4.0 ppm for wheat and 4.0 and 6.0 ppm for pea.     

Response of Eucalyptus tereticornis to inoculation with indigenous AM fungi in a semiarid alfisol achieved with different concentrations of available soil P

Eucalyptus tereticornis was grown in a green house in a low phosphorus (0.67 ppm Olsen's P) soil (Typic Haplustalf) inoculated with mixed indigenous arbuscular mycorrhizal (AM) fungi. Soil was amended to achieve P levels of 10, 20, 25, 30 and 40 ppm to evaluate the growth response and dependence of E. tereticornis to inoculation with AM fungi. A positive response to mycorrhizal inoculation was evident at the first two levels of soil P, i.e., at 0.67 and 10 ppm but not at the higher levels of soil P. Dry matter yield of inoculated plants beyond 20 ppm soil P was similar or even less compared to their uninoculated counterparts. Inoculated plants produced maximum dry matter (root and shoot) at 10 ppm soil P, whereas uninoculated plants did not produce until the level reached 20 ppm. The percentage root length colonized by AM fungi decreased from 31% to 3% as the concentration of P increased beyond 10 ppm soil P. Higher levels of soil P depressed the AM colonization significantly. Inoculated plants had higher shoot P and N contents compared to their uninoculated counterparts at all levels of soil P. However, at the first two lower levels of soil P, inoculated plants showed significantly higher shoot P and N contents over their respective uninoculated counterparts. The increasing shoot P accumulation beyond 10 ppm did not enhance dry matter yields. Inoculated plants had lower values of phosphorus utilization efficiency (PUE) and nitrogen utilization efficiency (NUE) at all levels of soil P except at the unamended level (0.67 ppm) where the inoculated plants showed higher values of NUE compared to uninoculated control plants. Taking dry matter yield into consideration, Eucalyptus plants were found to be highly dependent on 10 ppm of soil P for maximum dry matter production. Any further amendment of P to soil was not beneficial neither for AM symbiosis nor plant growth.     

Effects of boron and limestone on cereal yields and on B and N concentration of plant tissue

Summary Rates of added B up to 1.8 kg/ha had no effect on grain yield, but at rates of 2.24 kg/ha and higher it decreased yield of both barley and wheat. Lime-stone applications up to 4000 kg/ha did not induce B deficiency at low levels of B or alleviate B toxicity at high B levels in the two crops. Liming increased barley yields where soil pH was less than 5.8 but gave no yield response when soil pH exceeded 5.8. In general, liming did not decrease the B concentration of boot stage tissue (b.s.t.) except in barley at 1.8 kg B/ha on Location 1, where liming to pH 6.3 and 6.6 decreased B in b.s.t. from 16.4 to 12.2 and 11.4 ppm. The applications of B generally increased the N concentration of wheat grain where yields decreased due to B toxicity. Contribution no. 360, Research Branch, Research Station, Charlottetown, Prince Edward Island, Canada, C1A 7M8. Contribution no. 360, Research Branch, Research Station, Charlottetown, Prince Edward Island, Canada, C1A 7M8.     

土壤水分对两个冬小麦品种产量和竞争能力的影响

研究了黄土塬区两个旱作冬小麦品种(长武135和平凉40,前者是后者的换代品种)在不同土壤水分条件下竞争能力和产量形成的关系。研究设2种土壤水分条件(土壤含水量为田间最大持水量的75%～80%和40%～45%),采用生态替代法设计了同一播种密度的6个播种比例组合的盆栽试验。低水分单播条件下,长武135具有较高的产量(长武135为27.59g/pot,平凉40为24.91g/pot),而混播条件下平凉40在产量和相对产量上较长武135品种具有明显的竞争优势。高水分条件下,平凉40产量随播种比例的减小下降较快(长武135产量曲线斜率35.468,平凉40为36.237)。平凉40低水分单播时花后干物质积累量较少(长武135为0.67g/pot,平凉40为0.55g/pot),而混播时较多(长武135各比例均值0.58g/pot,平凉40为0.71g/pot),导致了平凉40品种单播时产量较低和混播时产量较高。平凉40地下生物量显著大于长武135(高水分条件下,长武135为10.03g/pot、平凉40为11.51g/pot;低水分条件下二者分别为8.41g/pot和10.69g/pot),且耗水量大(高水分条件下平凉40多耗水2.72kg/pot,低水分条件下多耗0.98kg/pot),而耗水量/地下生物量的比值平凉40低于长武135,从而平凉40品种单位根量消耗的水分低于长武135。总之,在两个生长属性接近的冬小麦品种中,老品种以较大的根系生物量赢得了较高的竞争能力,消耗了较多的水分,而新品种虽然根系生物量较低,耗水量较少,但籽粒产量却较高。亦即,小麦新品种籽粒产量的提高是与根系的减少和对水资源竞争能力的下降相伴随的。     

Assessment of the agronomic value of QTL on chromosomes 2H and 4H linked to tolerance to boron toxicity in barley (Hordeum vulgare L.)

Improved boron (B) tolerance has been an objective of barley breeding programs in regions where B toxicity occurs. Traits associated with B tolerance have been mapped on chromosomes 2H and 4H and it has been proposed that these be used for marker assisted selection for B tolerance. However, there has been little or no improvement in yield using this strategy. This study examined the reasons for the small yield differences among different lines of barley that differ in B tolerance. Experiments used backcross lines derived from crosses between the B-tolerant landrace Sahara 3771 and two adapted recurrent parents, Sloop and VB9104. Lines with different combinations of the Sahara 3771 alleles on chromosomes 2H and 4H were grown over three growing seasons at sites where barley is prone to B toxicity. Grain yields of the backcross lines were similar to or lower than those of the recurrent parents despite showing differences in the expression of B toxicity symptoms and in B concentration in vegetative tissue. There were few significant differences in grain yield among the backcross lines. Variation in dry matter production among the backcross lines in each of the three growing seasons was unrelated to shoot B concentrations while grain yield was correlated with shoot B concentration only among the backcross lines of VB9104 in one season. In this case the yield loss was 4% per 10 mg kg^-1 increase in shoot B concentration. Variation in shoot B concentration and yield across seasons was much greater than that observed among the different barley lines. Reduced B accumulation was associated with higher shoot sodium concentration among the Sloop backcross lines. The results suggest that yield gains from selection based largely on B exclusion and symptoms expression may be small and strongly affected by site and seasonal effects. In the regions where other soil constraints, such as soil salinity and micronutrient deficiencies are also important, reducing B uptake alone may have little effect on yield if these other soil properties are also limiting yields.     

The influence of lead,cadmium, and nickel on the growth of ryegrass and oats

Summary A 2⁴ factorial experiment was conducted under greenhouse conditions. Factors and levels in the experiment were soil pH at 4.5 and 6.4, and cadmium, lead, and nickel added to the soil to provide soil concentrations of 50, 250, and 50 ppm, respectively, above background levels. Two species were grown in succession in the same experimental pots. Ryegrass (Lolium hybridum Hausskn. cv. Tetrelite) was harvested three times and then one crop of oats (Avena sativa L. cv. Garry) was grown and harvested. Plant tissue concentrations of cadmium, lead, and nickel were monitored throughout the experiment.Addition of cadmium to the soil lowered the dry matter yields in all three ryegrass harvests and also reduced the yield of oat grain. The application of lead nitrate to the soil enhanced the yield of ryegrass obtained at the first harvest and also increased the yield of oat grain. Nickel, added to the soil at 50 ppm, was relatively innocuous to ryegrass and oats.The presence of added cadmium, lead, or nickel to the soil resulted in enhanced tissue concentrations of these metals in both ryegrass and oats. This effect was particularly enhanced by a soil pH of 4.5. A single exception to this observation was that lead was not detected, under any of the conditions of this experiment, in oat grain.The presence of lead in the soil enhanced cadmium concentrations in ryegrass tissues. The presence of cadmium in the soil decreased lead tissue concentrations in ryegrass and oat straw. Soil pH interacted with both nickel and lead in the second ryegrass harvest with subsequent changes in tissue cadmium concentrations. At a soil pH of 4.5, the presence of added lead or nickel to the soil significantly increased the ryegrass tissue cadmium concentration beyond that observed at a soil pH of 6.4 with or without enhanced nickel or lead concentrations.     

Mineral nutrition and growth of tropical maize as affected by soil acidity

Soil constraints linked to low pH reduce grain yield in about 10% of the maize growing area in tropical developing countries. The aim of this research was to elucidate the reasons for this maize yield reduction on an oxisol of Guadeloupe. The field experiment had two treatments: the native non-limed soil (NLI, pH 4.5, 2.1 cmol Al kg^–1, corresponding to 20% Al saturation), and the same soil limed 6 years prior to the experiment (LI, pH 5.3, 0 cmol Al kg^–1). The soils were fertilized with P and N. The above-ground biomass, root biomass at flowering, grain yield and yield components, leaf area index (LAI), light interception, radiation-use-efficiency (RUE), P and N uptake, soil water storage, and soil mineral N were measured during the maize cycle. The allometric relationships between shoot N concentration, LAI and above-ground biomass in LI were similar to those reported for maize cropped in temperate regions, indicating that these relationships are also useful to describe maize growth on tropical soils without Al toxicity. In NLI, soil acidity severely affected leaf appearance, leaf size and consequently the LAI, which was reduced by 60% at flowering, although the RUE was not affected. Therefore, the reduction in the above-ground biomass (30% at flowering) and grain yield (47%) were due to the lower LAI and light interception. At flowering, the root/shoot ratio was 0.25 in NLI and 0.17 in LI, and the root biomass in NLI was reduced by 64% compared to LI. Nitrogen uptake was also reduced in NLI in spite of high soil N availability. Nevertheless, shoot N concentration vs aboveground biomass showed a typical decline in both treatments. In NLI, the shoot P concentration vs above-ground biomass relationship showed an increase in the early stages, indicating that P uptake and root-shoot competition for the absorbed P in the early plant stages controlled the establishment and the development of the leaf area.     

Role of Ca2+ on Growth of Brassica campestris L. and B.juncea (L.) Czern & Coss under Na+ Stress

Root and shoot growth of Brassica campestris L.and B.juncea increased significantly(P0.01) with enhanced Ca2+ treatment along with 60 mM NaCl in the root medium.The maximum fresh mass of shoot and root in B.juncea was recorded at 10 mM Ca2+ concentration.The relative growth rate of shoot of both species reached its maximum at 8 mM of Ca2+ concentration.Average rate of Ca2+ intake(Ca) was higher in B.juncea than B.campestris.In B.juncea,the average transport of Ca2+ to shoot increased by 19%,38%,119%,125% and 169% compared with the control.Furthermore specific utilization rate of Ca2+ was higher in B.juncea than B.campestris.In B.campestris it increased by 9%,32%,41% and 59% at 4,6,8,and 10 mM of calcium in comparison to 2 mM Ca2+ treatment.At 4,6,8 and 10 mM of Ca2+ application,the increase in the leaf area ratio was 10,17,23 and 30%,respectively.In the shoot and root portions of B.campestris and B.juncea,Ca2+ had a linear relationship with potassium and sulfur,whereas it was in antagonism with sodium ion.     

Growth response to subsurface soil acidity of wheat genotypes differing in aluminium tolerance

Subsurface soil acidity coupled with high levels of toxic Al is a major limiting factor in wheat production in many areas of the world. This study examined the effect of subsurface soil acidity on the growth and yield of two near-isogenic wheat genotypes differing in Al tolerance at a single genetic locus in reconstructed soil columns. In one experiment, plants were grown in columns with limed topsoil and limed or acidic subsurface soils, and received water only to the subsurface soil at a late part of the growth period. While shoot dry weight, ear number and grain yield of Al-tolerant genotype (ET8) were not affected by subsurface soil acidity, liming subsurface soil increased shoot weight and grain yield of Al-sensitive genotype (ES8) by 60% and ear number by 32%. Similarly, root length density of ET8 was the same in the limed and acidic subsurface soils, while the root length density of ES8 in the acidic subsurface soil was only half of that in the limed subsurface soil. In another experiment, plants were grown with limed topsoil and acidic subsurface soil under two watering regimes. Both genotypes supplied with water throughout the soil column produced almost twice the dry weight of those receiving water only in the subsurface soil. The tolerant genotype ET8 had shoot biomass and grain yield one-third higher than ES8 when supplied with water throughout the whole column, and had yield 11% higher when receiving water in the subsurface soil only. The tolerant genotype ET8 produced more than five times the root length in the acidic subsurface soil compared to ES8. Irrespective of watering regime, the amount of water added to maintain field capacity of the soil was up to 2-fold higher under ET8 than under ES8. The results suggest that the genotypic variation in growth and yield of wheat grown with subsurface soil acidity results from the difference in root proliferation in the subsurface soil and hence in utilizing nutrient and water reserves in the subsurface soil layer.     

Response of barley and wheat to phosphorus in the presence of chloride and sulphate salinity

Summary The study was conducted in a greenhouse and under field conditions. In the greenoouse, barley was grown to maturity in pots on a sandy soil which contained 80 and 120 meq/l of chloride and sulphate dominant salts in its saturation extract, to which 0, 10, 25 and 50 ppm P were added. In the field study, wheat was grown on loamy sand soils having 0, 25, 50 and 75 kg/ha added P levels and irrigated with either Cl- or SO₄-dominant saline waters (EC=15–19 mmhos/cm). The results of the greenhouse study indicated that at maturity barley straw and grain yield was significantly increased by 50 ppm of added P both on the non-saline control and the Cl-treatments. However, 25 ppm P was optimal on the SO₄-treatments. The Cl content of plants was significantly decreased and S was increased with the increase in the P content of soil. A synergistic relation between the S and P content of barley shoots was observed. In the field study wheat grain yield responded significantly to P applications upto 50 kg/ha level on the Cl-site and there was no response to applied P on the SO₄-site, although the former contained more Olsen's P than the latter. The results suggested that P requirement of wheat and barley was greater on Cl- than on SO₄-salinity.     

Tolerance of peanut to excess boron

The tolerance ofArachis hypogaea cv. Shulamit to high concentrations of B in nutrient solution, [B]o, was determined under greenhouse conditions that promoted the production of vegetative dry matter. Plants grew in large containers in which a root zone of nutrient solution was separated from a pod zone of soil. Grain yield was reduced at a calculated [B]o-threshold of 0.29 mM, which was associated with a concentration of B in the vegetative shoots that was approximately four times larger than the control. Symptoms of B toxicity occurred on leaves as young as the third unfolded leaf from the shoot apex before the [B]o-threshold. Excess B caused a relatively larger decrease in pod number than in vegetative shoot weight, which was high in all treatments (78 g d.wt/plant) and it did not decrease single grain weight. It was suggested that the tolerance of grain development to excess B was a consequence of the high ratio of vegetative matter to pod number.     

分期施氮与CO2浓度升高对小麦光合及其物质积累和产量的互作效应

采用开顶式气室和盆栽方法,以冬小麦品种‘小偃22’为材料,探讨了分期施氮与CO2浓度升高对小麦抽穗期和灌浆中期旗叶光合、地上部物质积累和产量的互作效应.结果显示:(1)不施氮条件下CO2浓度升高对小麦旗叶叶绿素含量(SPAD)和可溶性蛋白含量、光合能力、地上部花后干物质和氮素累积量、籽粒产量的影响不明显(P>0.05)或产生显著负效应;在施氮(300mg/kg土)条件下各指标均不同程度增加,且大多数达到显著水平.(2)与氮肥全部基施相比,分期施氮时CO2浓度升高使灌浆期旗叶光合能力、地上部花后干物质和氮素累积以及产量增加的幅度较大,其中以播前、返青期和孕穗期施氮比例为5∶3∶2时最明显.研究表明,适当分期施氮可能更有利于发挥CO2浓度升高对冬小麦的增产作用.     

RESPONSE OF CHLORELLA PYRENOIDOSA TO ALUMINUM AND LOW pH12

Chlorella pyrenoidosa, a green alga which has no measurable Ca requirement, tolerated much higher Al concentrations in solution than higher plants which require considerable Ca. This alga also gave significant positive yield responses to Al concentrations between 1.5 and 12 ppm (added at pH 4.6). The positive Al response was not attributable to V, Cr, Ni, Co, W, or Ti contaminants in the Al salt. A strain of C. pyrenoidosa having even greater Al tolerance was isolated, by subjecting the original Strain I (Fitzgerald) culture to increasing Al stress. This strain, I-Al, grew in stagnant cultures containing 48 ppm Al at an initial pH of 4.2. Its yield also was not significantly decreased by 48 ppm Al in aerated cultures when both inoculum and solution pH were 4.6. Under the same conditions the original Strain I organism was injured by 3 and 6 ppm Al and was killed by 12 ppm. Algal strains which differ in Al tolerance may be useful in (1) studies on the mechanism of Al toxicity and mineral nutrition in general; and (2) in raising the pH, precipitating Al, and thereby detoxifying Al-containing acid mine drainage water and commercial wastes.     

Ameliorative role of zinc on maize growth (Zea mays L.) under salt-affected soil conditions

A greenhouse experiment, growing maize for six weeks, was conducted to evaluate the ameliorative role of Zn (0 and 10 ppm Zn) under saline (ECe4, 8 and 12 mmhos/cm), Sodic (ESP 10, 20 and 30) and saline-sodic (all possible combinations of above salinity and sodicity levels), and normal soil conditions using a sandy loam (Typic Ustochrepts) soil sample.Zinc ameliorated plant growth under salt-affected soil conditions. Ameliorative effect was more under sodic than under saline or saline-sodic soil conditions. Shoot yield decreased with Salinity level of 12 mmhos/cm, and ESP 30 and adverse effects were accentuated with increasing level of ESP and Salinity, respectively.Shoot Zn increased with applied Zn. Increasing sodicity in soil under Zn deficient or low salinity conditions generally decreased shoot Zn, whereas the low level of soil salinization counteracted the adverse effect of high sodicity. Shoot Na increased but K decreased with increasing sodicity and salinity in soil. Shoot Na decreased but K increased with applied Zn. Shoot Ca increased with salinity levels of 4 and 8 mmhos/cm, but decreased with 12 mmhos/cm at 0 Zn level. Sodicity decreased shoot Ca, whereas Zn counteracted adverse effect of high sodicity. Shoot Mg generally increased with increasing salinity, but decreased with increasing sodicity. Zinc had no definite effect. Shoot Ca/Na and K/Na ratios were widened with Zn and narrowed down with high ESP.The effects of salinity, sodicity, and Zn on plant growth and its composition were generally associated with their respective roles in dry matter production, and inter-ionic relationships among Ca, Mg, K, Na and Zn in soils and plants.Contribution from the Department of Soils, Haryana Agricultural University, Hissar, 125004, Indiaformer Research Fellow, respectively.     

钙、硼对花生生长、产量和品质的影响

在土壤代换性钙和有效硼含量分别为0.84me/100g和0.163mg/kg的条件下,研究了施钙、施硼及钙、硼配施对花生生长、产量和品质的影响。结果表明,施用钙肥能提高花生的产量和品质;施用硼肥能改善品质,但在产量上却产生负效应;钙、硼配施也能提高产量,但主效应仍然是钙。施用钙硼肥料不但使花生成熟期植株中钙、硼含量提高,而且种植花生后土壤中的钙、硼残留量也明显增加。     

Response of Douglas fir seedlings to phosphorus fertilization and influence of temperature on this response

Summary Effects of P fertilizers on growth of Douglas fir (Pseudotsuga menziesii var.menziesii (Mirb.) Franco.) seedlings were examined in pots and nursery beds. In pot experiments levels of P equivalent to 300 kg/ha were adequate for maximum growth over 14–18 weeks and resulted in available soil P levels of 80 ppm after 15 weeks' growth. Maximum growth in pots was obtained with shoot P concentrations of 0.18%–0.20%, with higher values at lower temperatures, but the optimum concentration for one-year old (1-0) nursery seedlings was 0.16% P. Growth of seedlings was greatly restricted at a soil temperature of 5°C and an air temperature of 12°C. At a soil temperature of 10°C and an air temperature of 14°C seedling P requirement was greater than at soil and air temperatures of 20°C.Comparison showed that monammonium phosphate was more effective than calcium superphosphate in stimulating growth in pots and nursery. Triple superphosphate was also effective in the nursery. Diammonium phosphate, potassium dihydrogen phosphate and phosphoric acid had no advantages as P sources in the nursery. Available P levels of 100–130 ppm, in the loamy sand and sandy loam nurseries studied, and needle P concentrations of 0.18%, when sampled in October, were associated with maximum growth of two-year old (2-0) seedlings.P fertilization decreased root/shoot ratio, but did not alter the allometric relationship of shoot to root. Improving P status from a low level increased root growth capacity in 2-0 seedlings and P fertilization of potted seedlings increased dry weight/height ratio. Uptakes per seed bed ha of 236 kg N, 31 kg P, 81 kg K and 73 kg Ca by 2-0 seedlings were comparable with, or greater than, uptake rates of agricultural crops. Recoveries of 6–11% of P from fertilizer were recorded in the nursery.     

Differential response of rye,triticale, bread and durum wheats to zinc deficiency in calcareous soils

Field and greenhouse experiments were carried out to study the response of rye (Secale cereale L. cv. Aslim), triticale (× Triticosecale Wittmark. cv. Presto), two bread wheats (Triticum aestivum L, cvs. Bezostaja-1 and Atay-85) and two durum wheats (Triticum durum L. cvs. Kunduru-1149 and C-1252) to zinc (Zn) deficiency and Zn fertilization in severely Zn-deficient calcareus soils (DTPA-Zn=0.09 mg kg^-1 soil). The first visible symptom of Zn deficiency was a reduction in shoot elongation followed by the appearance of whitish-brown necrotic patches on the leaf blades. These symptoms were either absent or only slight in rye and triticale, but occurred more rapidly and severely in wheats, particularly in durum wheats. The same was true for the decrease in shoot dry matter production and grain yield. For example, in field experiments at the milk stage, decreases in shoot dry matter production due to Zn deficiency were absent in rye, and were on average 5% in triticale, 34% in bread wheats and 70%, in durum wheats. Zinc fertilization had no effect on grain yield in rye but enhanced grain yield of the other cereals. Zinc efficiency of cereals, expressed as the ratio of yield (shoot dry matter or grain) produced under Zn deficiency compared to Zn fertilization were, on average, 99% for rye, 74% for triticale, 59% for bread wheats and 25% for durum wheats.These distinct differences among and within the cereal species in susceptibility to Zn deficiency were closely related to the total amount (content) of Zn per shoot, but not with the Zn concentrations in shoot dry matter. For example, the most Zn-efficient rye and the Zn-inefficient durum wheat cultivar C-1252 did not differ in shoot Zn concentration under Zn deficiency, but the total amount of Zn per whole shoot was approximately 6-fold higher in rye than the durum wheat. When Zn was applied, rye and triticale accumulated markedly more Zn both per whole shoot and per unit shoot dry matter in comparison to wheats.The results demonstrate an exceptionally high Zn efficiency of rye and show that among the cereals studied Zn efficiency declines in the order rye>triticale>bread wheat>durum wheat. The differences in expression of Zn efficiency are possibly related to a greater capacity of efficient genotypes to acquire Zn from the soil compared to inefficient genotypes.     

根区水肥空间耦合对冬小麦生长及产量的影响

利用管栽试验研究了根区不同湿润方式（整体湿润、上湿下干、上干下湿）、施肥方式（整体施肥、上层施肥、下层施肥）及其耦合对冬小麦不同生育期生长及产量的影响.结果表明：下层施肥方式显著降低了分蘖期冬小麦的株高和叶面积,而不同湿润方式对分蘖期株高和叶面积的影响不显著,拔节期水肥同区方式的株高大于水肥异区方式,表现出协同耦合效应.上干下湿方式和下层施肥方式显著降低了根系干物质量、地上部干物质量和总干物质量,上层施肥方式有利于增加冬小麦生物量,而上湿下干方式与施肥处理对地上部干物质量和总干物质量的耦合效应明显.水肥同区处理的根冠比高于水肥异区处理;上干下湿方式的水分利用效率显著高于整体湿润和上湿下干方式,水肥同区处理的水分利用效率高于水肥异区处理,但下层施肥方式的水分利用效率较低.与上干下湿方式相比,上湿下干和整体湿润方式的冬小麦单穗粒数分别增加了41.7%和61.9%,上层施肥和整体施肥方式的单穗粒数高于下层施肥方式,上湿下干方式与施肥处理对小麦产量及产量构成因素（除千粒重外）的水肥耦合效应明显.不同水肥处理主要通过影响单穗粒数来影响冬小麦产量.     

The combined effect of soil salinity and CCC on dry matter accumulation and yield of wheat plants

The rise in soil salinity level tended to decrease shoot dry weight, and, grain yield per plant and, to some extent, weight of I grain. This effect was usually more pronounced in the presence of CCC. On the other hand, the shoot dry weight was increased by CCC in salinity absence but the reverse at 0.8 % salinization degree. The grain yield per plant was raised by CCC in the presence or absence of salinity, particularly in the latter case. The dry matter accumulation in the shoot system (at earing stage) rather than grain yield tended to be much more affected, whether regarding the negative response to salinity or the positive one to CCC.