不同施肥处理对曼地亚红豆杉‘Hicksii’生长和紫杉醇含量的影响

采用L9（3^4）正交实验设计,研究了温室盆栽和田间栽培条件下,不同氮、磷、钾施用水平对曼地亚红豆杉‘Hicksii’（Taxus media‘Hicksii’）生长及紫杉醇含量的影响。结果表明,不同的氮、磷、钾施用水平对曼地亚红豆杉‘Hicksii’盆栽苗和田间栽培苗的生长量、枝叶产量和紫杉醇含量有显著影响,影响效应从大至小依次为氮、磷、钾。根据生长综合指标确定最有利于曼地亚红豆杉幼苗生长的氮、磷、钾施用量分别为400、66和200mg·L^-1;最有利于紫杉醇积累的氮、磷、钾施用量分别为200、66和133mg·L^-1。此外,曼地亚红豆杉‘Hicksii’田间栽培苗的生长量、枝叶产量和紫杉醇含量显著高于盆栽苗。     

Sodium in the mineral nutrition ofAvena Sativa

Summary In pot experiments with oats on sandy soil poor in sodium and potassium a study was made of the effect of the addition of Na₂SO₄ and K₂SO₄ on the mineral composition of the straw.The addition of sodium at 200 ppm Na significantly increased the phosphorus content of the straw and there was a slight further increase with 200 ppm Na plus 200 ppm K, but the phosphorus content never exceeded 0.13 per cent.Sodium and potassium caused a highly significant decrease in the silica content of the straw. Decreased lodging in soils inundated with sea water can therefore not be ascribed to an increase of silica content.The calcium and the cellulose contents of the straw were both significantly reduced by sodium and potassium.     

Evaluation and control of the nutritional status of cereals

Summary Based on grain yield and the chemical composition of grain and straw at maturity, a quantitative method of estimating the nutritional status of the young plant and the corresponding nutritional conditions of the growth medium was developed from results of three years' of factorial fertilizer pot experiments with oats and spring wheat.In trophogenetic methods, yield and chemical composition of older plants form the basis for the conclusion on soil fertility at sowing time with the aim to decide on future fertilizer policy.Contrary to earlier trophogenetic methods, the present method includes the nutritional status of the young plant—based on a well-defined stage of development (DMw-level) and pure-effect concentrations of nutrients—as an intermediate link in the above conclusion.The method follows the reversed direction of procedures based on the models used for diagnosis and prognosis of grain yield and chemical composition of plant parts at maturity previously outlined.The reliability of the method was proved by comparing trophogenetically determined and experimentally obtained nutrient concentrations in the young plant. The coefficients of regression and correlation were both close to 1, and the latter was highly significant.Together with the methods of diagnosis, prognosis and therapy, trophogenesis completes the framework enclosing all possibilities of using the plant analysis in evaluation and control of the nutritional status of the plant.     

Response of cowpea (Vigna unguiculata) to inoculation with VA-mycorrhizal fungi and to rock phosphate fertilization in some unsterilized Nigerian soils

Summary The effects on cowpea of inoculation with vesicular-arbuscular (VA) mycorrhizal fungi and rock phosphate (RP) fertilization were studied in pots using Alagba and Araromi series soils and in the field on Alagba, Apomu and Egbeda series soils. Inoculation of the plants with VA-mycorrhizal fungi caused very rapid infection of the roots. A higher per cent mycorrhizal infection was maintained during subsequent plant growth in the field. RP application reduced the degree of infection without affecting plant growth in the field and in pot experiments. Nodulation, nitrogen fixation and utilization of RP were increased by inoculation with mycorrhizal fungi in the pot experiments but not in the field experiments. In the pot experiments, inoculated plants supplied with RP flowered earlier, and took up more phosphorus than either inoculated plants without RP or uninoculated plants. The largest response to inoculation in terms of shoot dry matter, nodule yield and nitrogen content of shoots was obtained in Alagba soil under both pot and field conditions.IITA Journal Series Paper No. 136.     

Characteristics and Quantitative Analysis of K,Na, Ca,Mg and S Contents in the Dominant Plant Species on the Hutubi Cattle Stock Farm Area,Xinjing

The characteristics on K, Na, Ca, Mg and S contents of 25 plant species were analysed at the grassland on the Hutubi Cattle Stock Farm area, Xinjiang. The level of content is in the order of Na>S>K>Mg>Ca. Different plant species have considerable variation in contents of Na and S, for example, the contents of Na and S are more than 100000 ppm and 30000 ppm respectively in Suaeda physophara and Halocnemum strobilaceum and less than 30000 ppm and 4000 ppm respectively in Phragmites cornmunis and Aeluropus littoralis; their interspecific coefficient of variation (c. v. ) are 95.10 % and 63.16% respectively. The interspecific c. v. of K content, 34.42 %, is the lowest. The contents of K, Na, Ca and S in all innerspecific plants at different sites are less various than interspecific ones; the content of Mg in some innerspecific plants is more various than in interspecific ones. The analysis of correlation between contents of elements in plants and soil shows that Nitraria sibirica is the only plant specie whose coefficient of correlation (c. c. ) of Na content in plant with that in soil reaches the significant negative level in seven plant species; among 5 elements in plants, the c. c. between Na and Ca reaches the significant negative corrrelative level, the c. c. between Na and S reaches the significant positive correlation level. The results of classification and ordination of TWINSPAN and DCA of 25 plant species using the data of 5 elemental contents show that seven plant species, for example, H. strobilaceum, S. physophora, Kalidium foliatum, K. caspicum, etc. are Na and S type plant; Phragmites communis, Achnatherum splendens, etc. are Na and K type plant.     

Effect of the arbuscular mycorrhizal symbiosis upon uptake of cesium and other cations by plants

Pot experiments were set up to determine the species-specific uptake of cesium (Cs) by mycorrhizal (AM) and non-mycorrhizal (non-AM) plants. Using stable Cs and K application, side-effects of mineral fertilization (K) on AM development and uptake of Cs and the other cations Na, Ca and Mg were investigated. AM colonization by the fungus Glomus mosseae led to a significant decrease in shoot Cs content of Agrostis tenuis from the first (4 weeks) to the third harvest (8 weeks). With regard to the root system, statistically significant differences were observed from the first (4 weeks) to the second harvest (6 weeks). Supply of additional K produced a significant decrease in Cs uptake by both AM and non-AM plants over a 10-week period. In the case of AM plant shoots, K fertilization did not very effectively reduce Cs uptake by A. tenuis. Cs contents of fertilized AM roots were similar to non-AM controls. Potassium application resulted in an increase in K content and a slight reduction in Na and Mg contents of shoots and roots. Without K fertilization, the Na content of non-AM controls was significantly enhanced over AM shoots. Shoot and root Ca contents were generally higher without than with K addition. Negative side-effects of K fertilization as a countermeasure to Cs uptake were not observed in relation to AM development. The intensity of colonization by G. mosseae was not significantly depressed by K treatment. AM development in plants appeared to decrease Cs uptake, at least at moderate nutrient levels. It is possible that Cs is sequestered by AM extraradical fungal hyphae and consequently not transferred to the plant to the extent found in non-AM roots. Accepted: 6 November 2000     

喀喇昆仑、昆仑山地区植物中一些元素的自然含量特征

 本文论述了喀喇昆仑、昆仑山地区87种植物12个元素含量的特征。在含量水平上>10000ppm的元素有K,Ca,800—5000ppm的元素为Na、Mg,Fe、Al,10—100ppm的元素有Ba、Sr、Ti,Mn,V与Be的含量<10ppm。大多数植物Fe、V,Sr的含量高于一般的自然含量。植物中K含量的频数分布呈正态分布,其余元素的频数分布呈对数正态分布。不同植物种元素含量差异较大,Na的变异系数最大,Ca、Mg含量的变异系数最小。同种植物在不同地点元素含量有较大差异,不同植物种差异也不同。如紫花针茅(Stipa purpurea)>垫状驼绒藜(Ceratoides compacta)>鼠麴凤毛菊(Saussurea gnaphaloides)。植物中元素含量之间的相关分析表明,Fe、Al,V,Ti之间分别达极显著相关水平。用植物中12个元素的资料,对22种植物进行分类和排序,区分出Na,K型植物和Fe,Al,V,Ba型植物。     

Effects of salinity and nitrogen on cotton growth in arid environment

The influences of different N fertilization rates and soil salinity levels on the growth and nitrogen uptake of cotton was evaluated with a pot experiment under greenhouse conditions. Results showed that cotton growth measured as plant height was significantly affected by the soil salinity and N-salinity interaction, but not by N alone. Cotton was more sensitive to salinity during the emergence and early growth stages than the later developmental stages. At low to moderate soil salinity, the growth inhibition could be alleviated by fertilizer application. Soil salinity was a dominated factor affecting cotton’s above-ground dry mass and root development. Dry mass of seed was reduced by 22%, 52%, and 84% respectively, when the soil salinity level increased from control level of 2.4 dS m^?1 to 7.7 dS m^?1, 12.5 dS m^?1 and to 17.1 dS m^?1, respectively. N uptake increased with N fertilization at adequate rates at both low and medium soil salinities but was not influenced by over N fertilization. At higher salinities, N uptake was independent of N rates and mainly influenced by soil salinity. The uptake of K decreased with soil salinity. The concentration of Na, Cl and Ca in plant tissues increased with soil salinity with highest concentrations in the cotton leaf.     

Effect of long-term organic and mineral fertilization strategies on rhizosphere microbiota assemblage and performance of lettuce

Long-term agricultural fertilization strategies gradually change soil properties including the associated microbial communities. Cultivated crops recruit beneficial microbes from the surrounding soil environment via root exudates. In this study, we aimed to investigate the effects of long-term fertilization strategies across field sites on the rhizosphere prokaryotic (Bacteria and Archaea) community composition and plant performance. We conducted growth chamber experiments with lettuce (Lactuca sativa L.) cultivated in soils from two long-term field experiments, each of which compared organic versus mineral fertilization strategies. 16S rRNA gene amplicon sequencing revealed the assemblage of a rhizosphere core microbiota shared in all lettuce plants across soils, going beyond differences in community composition depending on field site and fertilization strategies. The enhanced expression of several plant genes with roles in oxidative and biotic stress signalling pathways in lettuce grown in soils with organic indicates an induced physiological status in plants. Lettuce plants grown in soils with different fertilization histories were visibly free of stress symptoms and achieved comparable biomass. This suggests a positive aboveground plant response to belowground plant–microbe interactions in the rhizosphere. Besides effects of fertilization strategy and field site, our results demonstrate the crucial role of the plant in driving rhizosphere microbiota assemblage.     

Macro nutrient cation uptake by plants

Summary In pot experiments with barley, mustard, leek, lettuce and spinach, and in a field experiment with 30 cultivars of barley uptakes of K, Mg, Ca, Na and N were studied at varying concentrations and activities of these cations in the soil solution.The sum of macro cations (K, Mg, Ca, Na) in meq per 100 g aerial plant parts were independent of the chemical composition of the soil solution, but dependent on plant species and on the N concentration in the plant.The ratios of mean net inflows of Mg, Ca and K into plants and corresponding cation activity ratios (a_Mg/a_Ca and ) in the soil solution were linearly related and highly correlated under conditions in which growth rate and/or rate of incorporation into new tissues constituted the rate determining step of cation uptake. Consequently, mean net inflows of K, Mg and Ca were independent of ion concentration and ion activity of K, Mg or Ca in the soil solution under the conditions of constant activity ratio.The results agree with the concept that plants have a finite cation uptake capacity, and that plants are in a equilibrium-like state with the activities of K, Mg, and Ca ions in the soil solution. The results indicate that both ratios and content of exchangeable cations should be considered in our evaluation of soil test data.     

丛枝菌根真菌群落对白三叶草生长的影响

不同施肥处理影响AMF(Arbuscular mycorrhizal fungi)群体结构,然而不同AMF群体结构对植物的生长以及养分吸收的影响尚未见报道,试验利用盆栽实验研究了7种不同来源的丛枝菌根真菌(AMF)群落对白三叶草生长和N、P、K以及微量元素Cu、Zn、Mn的吸收的影响。7种AMF群落分离自长期定位施肥试验地,分别为NPK、OM、CK、1/2OM、NP、NK和PK。每年施肥量是300kg N/hm2,135kg P2O5/hm2,300kg K2O/hm2。有机肥处理的N、P、K养分量与试验地NPK处理含量相同,原料以粉碎的麦秆为主,加上适量的大豆饼和棉仁饼,有机肥经堆制发酵后施用。试验土壤采用封丘试验地土壤,经灭菌处理。试验结果表明,接种不同AMF群落均能促进三叶草的生长,对养分吸收则表现不同。分离自CK试验地的AMF群落对三叶草侵染率显著低于其它6种AMF群落。分离自1/2OM和OM试验地的AMF群落较分离自NPK、CK、NP和NK的AMF群落显著促进了三叶草对P的吸收;各种AMF群落都促进了对N和K的吸收;分离自OM、CK、1/2OM、NP、NK试验地的降低了三叶草植株N含量;分离自NPK试验地的AMF群落提高了三叶草植物K含量;对于Cu、Zn、Mn元素的吸收,不同处理存在较大的差异。AMF群落对三叶草生长以及养分吸收贡献不同,这与不同施肥管理下不同AMF群落的优势种属的侵染率、养分转化以及菌丝发育及分布有关。     

Reuse potential of phosphorus-rich filter materials from subsurface flow wastewater treatment filters for forest soil amendment

The aim of this study was to test P-enriched filter materials from a wastewater treatment experiment regarding their fertilizing efficiency in pot experiments with silver birch (Betula pendula Roth.) seedlings. Tested materials included hydrated calcium-rich oil shale ash and well-mineralised peat. A mixture of peat and hydrated ash demonstrated the best results: seedlings grown on that mixture had the highest P concentration and an optimal N:P:K ratio in leaves. Hydrated ash has a low concentration of heavy metals and almost the same composition as common lime fertilizers. The hydrated ash sediment and its combination with well-mineralised peat enriched with phosphorus in wastewater treatment filters are promising materials for forest soil fertilization.     

干旱胁迫与施氮对麻疯树幼苗渗透调节物质积累的影响

采用盆栽控水的方法,研究干旱胁迫(80％ FC、60％ FC、40％ FC和20％ FC)及施氮(N0 0 g·pot-1、N1 1.2 g·pot1、Nm3.6 g·pot-1和Nh6.0 g·pot-1)对麻疯树幼苗叶、茎和根部主要渗透调节物质积累的影响.结果表明:干旱胁迫条件下,麻疯树幼苗茎和根部的游离脯氨酸、可溶性蛋白和茎部可溶性糖大量积累,叶片中脯氨酸含量也随干旱胁迫程度的增加大幅度上升;Na+、Ca2+和Mg2+在麻疯树幼苗叶、茎和根中大量积累,而K+仅在茎中大量积累,叶片和根部K+含量略微上升.施氮对植株渗透调节物质的影响与干旱胁迫强度和施氮水平有关.在80％ FC和60％ FC水分条件下,增加N肥施用量能明显促进麻疯树幼苗各组分渗透调节物质的积累;在40％ FC水分条件下,Nh处理对渗透调节物质积累的促进作用减弱;而在20％ FC条件下,N1处理植株的渗透调节能力较高,Nm和Nh处理对植株渗透调节的促进作用不明显甚至转为抑制.     

The role of rock-phosphate-solubilizing fungi and vesicular–arbusular-mycorrhiza (VAM) in growth of wheat plants fertilized with rock phosphate

A total of 36 fungal species isolated from soil were tested for their ability to solubilize rock phosphate (RP) in agar plates. Most of these fungi were non-rock phosphate solubilizers, but two isolates, Aspergillus niger and Penicillium citrinum, had high activity. Liquid culture experiments revealed that both fungi caused a remarkable drop in pH of culture media and solubilized considerable amounts of phosphate. The effects on wheat of inoculation with vesicular–arbuscular mycorrhizal fungi and rock-phosphate-solubilizing fungi and fertilization with rock phosphate were studied in sterilized pot soils, nonsterilized pot trials and in field plot soils. Rock phosphate fertilization and inoculation with Glomus constrictum and rock-phosphate-solubilizing fungi (A. niger and P. citrinum) significantly increased dry matter yield of wheat plants under all experimental conditions. However, the effect was more evident in non- sterilized pot soils and in the field than in sterilized pots. Rock phosphate had no significant effect on the total phosphorus content of plants grown under pot conditions but it was significantly increased in field plots; the effect of inoculation with fungi (G. constrictum, A. niger and P. citrinum) on plant phosphorus was closely related to this in dry matter production. The greatest positive effect on growth and phosphorus contents of wheat plants was recorded in the treatments that received rock phosphate and were inoculated with a mixed inoculum of the three microorganisms used, followed by dual inoculation treatments of G. constrictum plus either A. niger or P. citrinum.     

Mechanism of tolerance in rice varieties differing in sodicity tolerance

Summary The performance of two rice varieties selected for sodicity tolerance and sensitivity was studied in pot culture. Tolerant variety CSR-1 showed much better survival, plant growth and yield as compared to the sensitive one (Basmati-370). Sensitive variety was characterized by higher reduction in growth yield, higher Na and lower K concentrations under sodicity in all the plant organs. Highest Na concentrations are in sensitive variety and its distribution is in the order of Senescent yellow leaves > Earheads > Stem > Younger green leaves. Analysis of different leaves revealed leaf to leaf gradients in terms of Na and K and Na/K ratio were lowest in the youngest leaf and highest in the oldest surviving leaf and these values were much higher in the sensitive variety. This showed that Na ions are mainly localised in the older leaves, which are shed and provide a secondary process of tolerance. Thus the tolerant variety is best marked by maintenance of K levels and much lower increases in Na in all the plant organs, especially earheads, inspite of their growing in highly sodic soils.     

The role of rock-phosphate-solubilizing fungi and vesicular–arbusular-mycorrhiza (VAM) in growth of wheat plants fertilized with rock phosphate

A total of 36 fungal species isolated from soil were tested for their ability to solubilize rock phosphate (RP) in agar plates. Most of these fungi were non-rock phosphate solubilizers, but two isolates, Aspergillus niger and Penicillium citrinum, had high activity. Liquid culture experiments revealed that both fungi caused a remarkable drop in pH of culture media and solubilized considerable amounts of phosphate. The effects on wheat of inoculation with vesicular–arbuscular mycorrhizal fungi and rock-phosphate-solubilizing fungi and fertilization with rock phosphate were studied in sterilized pot soils, nonsterilized pot trials and in field plot soils. Rock phosphate fertilization and inoculation with Glomus constrictum and rock-phosphate-solubilizing fungi (A. niger and P. citrinum) significantly increased dry matter yield of wheat plants under all experimental conditions. However, the effect was more evident in non- sterilized pot soils and in the field than in sterilized pots. Rock phosphate had no significant effect on the total phosphorus content of plants grown under pot conditions but it was significantly increased in field plots; the effect of inoculation with fungi (G. constrictum, A. niger and P. citrinum) on plant phosphorus was closely related to this in dry matter production. The greatest positive effect on growth and phosphorus contents of wheat plants was recorded in the treatments that received rock phosphate and were inoculated with a mixed inoculum of the three microorganisms used, followed by dual inoculation treatments of G. constrictum plus either A. niger or P. citrinum.     

Distribution of selected elements within flax plants as affected by FeEDDHA

Summary Flax growing on a calcareous soil in the greenhouse developed Mn toxicity symptoms. The toxicity was eliminated by application of 2 ppm FeEDDHA-Fe. FeEDDHA had major effects on distribution of Mn, Zn, Fe and P among selected plant parts. Application of the chelate reduced Mn concentration in older leaves, the tissue most susceptible to Mn toxicity, associated stem tissue, plant tops, and roots from 2295 to 133 ppm, 62 to 7 ppm, 550 to 34 ppm, and 42 to 34 ppm, respectively. Analysis of older leaves is recommended for diagnosing Mn toxicity in flax.FeEDDHA reduced Zn concentration in plant tops and this was chiefly reflected in greatly reduced leaf concentrations, especially in older leaves. FeEDDHA increased plant Fe concentration and the effect was greatest in root and older leaf tissues. The overall effect of FeEDDHA on P concentration was small but large increases occurred in younger leaf tissue due to application of the chelate. Relative distributions of K, Na, Ca, and Mg among plant parts were only slightly affected by FeEDDHA.     

Inhibition of Na+,K+-ATPase in Penaeus indicus postlarvae by lead

The plasma membrane/mitochondrial fractions of Penaeus indicus postlarvae contain Mg2+-dependent ATPase, Na+,K+-stimulated ATPase, Na+-stimulated ATPase and K+-stimulated ATPase. The Na+,K+-activated, Mg2+-dependent ATPase was investigated further in relation to different pH and temperature conditions, and at various concentrations of protein, ouabain, ATP and ions in the incubation medium. In vitro and in vivo effects of lead were studied on the enzyme activity. In vitro lead inhibited the enzyme activity in a concentration-dependent manner with an IC50 value of 204.4 microM. In correlation with in vitro studies, in vivo investigations (both concentration and time dependent) of lead also indicated a gradual inhibition in enzyme activity. A maximum decrease of 85.3% was observed at LC50 (7.2 ppm) of lead for concentration-dependent experiments. In time-dependent studies, the decrease was maximal (81.7%) at 30 days of sublethal exposure (1.44 ppm). In addition, the substrate- and ion-dependent kinetics of Na+,K+-ATPase was studied in relation to in vitro exposure of lead; these studies suggest a non-competitive type of inhibition.     

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.     

In-field labeling of western corn rootworm adults (Coleoptera: Chrysomelidae) with rubidium

Field and laboratory studies were conducted in 2000 and 2001 to determine the feasibility of mass marking western corn rootworm adults, Diabrotica virgifera virgifera LeConte, with RbCl in the field. Results showed that application of rubidium (Rb) in solution to both the soil (1 g Rb/plant) and whorl (1 g Rb/plant) of corn plants was optimal for labeling western corn rootworm adults during larval development. Development of larvae on Rb-enriched corn with this technique did not significantly influence adult dry weight or survival. Rb was also highly mobile in the plant. Application of Rb to both the soil and the whorl resulted in median Rb concentrations in the roots (5,860 ppm) that were 150-fold greater than concentrations in untreated roots (38 ppm) 5 wk after treatment. Additionally, at least 90% of the beetles that emerged during the first 3 wk were labeled above the baseline Rb concentration (5 ppm dry weight) determined from untreated beetles. Because emergence was 72% complete at this time, a significant proportion of the population had been labeled. Results from laboratory experiments showed that labeled beetles remained distinguishable from unlabeled beetles for up to 4 d postemergence. The ability to efficiently label large numbers of beetles under field conditions and for a defined period with virtually no disruption of the population provides an unparalleled opportunity to conduct mark-recapture experiments for quantifying the short-range, intrafield movement of adult corn rootworms.