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1.
Low supply of nutrients is a major limitation of forage adaptation and production in acid soils of the tropics. A glasshouse study was conducted to find differences in plant growth, nutrient acquisition and use, among species of tropical forage grasses (with C4 pathway of photosynthesis) and legumes (with C3), when grown in two acid soils of contrasting texture and fertility. Twelve tropical forage legumes and seven tropical forage grasses were grown in sandy loam and clay loam Oxisols at low and high levels of soil fertility. After 83 days of growth, dry matter distribution among plant leaves, stems, and roots, leaf area production, shoot and root nutrient composition, shoot nutrient uptake, and nutrient use efficiency were measured. Soil type and fertility affected biomass production and dry matter partitioning between roots and shoots. The allocation of dry matter to root production was greater with low soil fertility, particularly in sandy loam. The grasses responded more than the legumes to increased soil fertility in both shoot and root biomass production. Leaf area production and the use of leaf biomass for leaf expansion (specific leaf area) were greater in legumes than in grasses, irrespective of soil type and fertility. But soil type affected shoot biomass production and nutrient uptake of the grasses more than those of the legumes. There were significant interspecific differences in terms of shoot nutrient uptake. The grasses were more efficient than legumes in nutrient use (grams of shoot biomass produced per gram of total nutrient uptake) particularly for nitrogen (N) and calcium (Ca).  相似文献   

2.
Abstract

Dry matter accumulation and nutrient uptake patterns of crops must be determined to optimize fertilizer scheduling. This study assesses the dry matter accumulation and nutrient uptake patterns of onion seed crop. Plant samples were collected between 0 and 120?days after planting, and their nutrient content was analyzed to determine the dry matter accumulation and nutrient uptake patterns. The quantity and period of nutrient uptake and the mobility of nutrients within the plant parts varied for different nutrients. The absorption of nitrogen (N) and potassium (K) was the highest during vegetative stage, whereas phosphorus (P) and sulfur (S) uptake was the highest during flower initiation stage. N, P, K, and S, which had accumulated in the vegetative parts, moved from the senesced vegetative parts to the inflorescence during the reproductive stages owing to their high mobility in the phloem. The onion plants continued to absorb zinc, copper, manganese, and iron throughout their growth owing to the immobility of these elements in plant system. The result of this study may facilitate efficient scheduling of fertilizer application to increase nutrient uptake and yield.  相似文献   

3.
The use of organic materials as a source of nutrients on agricultural lands ameliorates soil physical properties as well as being an environmentally friendly way of disposing of their wastes. This study was conducted to determine effects of three organic materials (poultry litter, cattle manure, leonardite) on yield and nutrient uptake of silage maize. Poultry litter and cattle manure were applied based on phosphorus (P) or nitrogen (N) requirements of the crop whereas leonardite was applied only one dose (500 kg ha?1) and also combined with three inorganic fertilizer doses (100%, 75%, 50% of recommended inorganic fertilizer dose). According to the results, the highest green herbage yield and nutrient uptake values were observed in LEO-100 whereas N-based treatments significantly decreased yield and nutrient uptake of silage maize. The use of organic materials as a combination with inorganic fertilizer in silage maize cultivation is highly beneficial for sustainable forage production.  相似文献   

4.
《Applied soil ecology》1999,11(2-3):135-146
Most studies of nutrient cycling in arctic ecosystems have either addressed questions of plant nutrient acquisition or of decomposition and mineralization processes, while few studies have integrated processes in both the soil and plant compartments. Here, we synthesize information on nutrient cycling within, and between, the soil/microbial and the plant compartments of the ecosystems and integrate the cycling of nutrients with the turnover of organic matter and the carbon balance in tundra ecosystems. Based on this compilation and integration, we discuss implications for ecosystem function in response to predicted climatic changes.Many arctic ecosystems have high amounts of nutrients in the microbial biomass compared to the pools in the plant biomass both due to large nutrient-containing organic deposits in the soil and low plant biomass. The microbial pools of N and P, which are the most commonly limiting nutrients for plant production, may approach (N) or even exceed (P) the plant pools. Net nutrient mineralization is low, the residence time of nutrients in the soil is long and the nutrients are strongly immobilized in the soil microorganisms. This contributes to pronounced nutrient limitation for plant productivity, implies that the microbial sink strength for nutrients is strong and that the microbes may compete with plants for nutrients, but also that they are a potential source of plant nutrients during periods of declining microbial populations. The extent of this competition is poorly explored and it is uncertain whether plants mainly take up nutrients continuously during the summer when the microbial activity and, presumably, also the microbial sink strength is high, or whether the main nutrient uptake occurs during pulses of nutrient release when the microbial sink strength declines.Improved knowledge of mechanisms for plant-microbial interactions in these nutrient-limited systems is important, because it will form a basis also for our understanding of the C exchange between the ecosystems and the atmosphere under the predicted, future climatic change. High microbial nutrient immobilization, i.e. low release of plant-available nutrients, paired with high microbial decomposition of soil organic matter will lead to a loss of C from the soil to the atmosphere, which may not be compensated fully by increased plant C fixation. Hence, the system will be a net source of atmospheric C. Conversely, if plants are able to sequester extra nutrients efficiently, their productivity will increase and the systems may accumulate more C and turn into a C sink, particularly if nutrients are allocated to woody tissues of low nutrient concentrations.  相似文献   

5.
红芸豆养分限制因子及养分吸收、积累和分配特征研究   总被引:1,自引:2,他引:1  
研究红芸豆养分限制因子、植株干物质和氮、磷、钾养分积累及分配规律,可为红芸豆合理施肥及高产栽培提供理论依据。大田试验条件下,以‘英国红’红芸豆为试材,设置缺素试验,采集全施肥区植株样品,分析研究红芸豆不同生育时期各器官干物质量、养分含量及积累量。结果显示,氮磷钾配合全施显著提高红芸豆产量;缺氮、缺磷、缺钾处理与全施肥处理相比,产量分别降低14.2%、8.0%和11.3%,表明影响红芸豆产量的限制因子为氮钾磷。在整个生育期,红芸豆干物质累积速率先升高后降低;根、茎、荚皮和豆粒干物质累积量呈上升趋势,叶干物质在收获期有下降趋势,收获时不同部位干物质量为豆粒茎≈荚皮叶片根。随生育期推进,茎、叶和荚皮中氮含量呈递减趋势,豆粒中氮含量呈递增趋势,而各器官磷、钾含量呈递减趋势。盛花期到结荚期是养分累积最大期,其氮、磷、钾吸收量分别占整个生育期吸收总量的28.14%、49.22%和56.20%;不同器官吸收累积氮、磷、钾量不同,成熟期豆粒、叶、茎和根中均为累积氮最多、钾次之、磷最少,荚皮中累积钾最多、氮次之、磷最少。每生产100 kg红芸豆需供给N 4.37 kg、P2O5 2.38 kg、K2O 3.53 kg,比例为1∶0.54∶0.81。  相似文献   

6.
ABSTRACT

Plant residue material produced compost is an organic fertilizer source and it is commonly used for soil amendments. Also in order to reduce the amount of chemical fertilizers need mycorrhizal inoculation can be used as an agricultural strategy. Thus, the aim of the research is to examine the effect of several residue materials produced compost and mycorrhizae fungi with two growth media on leek plant growth, nutrient uptake, and mycorrhizae spores’ production.

Eight different row organic materials and animal manures were used as compost production during 8 months. Leek (Allium porrum L.) plants were inoculated with Funneliformis mosseae and Claroideoglomus etunicatum with a level of 1000-spore per pot. The leek plant was analyzed for determination of nutrient concentration, root colonization, spore production, and shoot/root dry weight.

The composts were made from domestic waste, animal manure (bovine animal), animal manure (ovine animal), and different plant materials were determined to be the most suitable compost material for plant growth and mycorrhizal spore production compared to the rest of compost material. Mycorrhizal inoculation significantly increased leek plant growth and nutrient uptake especially phosphorus (P), potassium (K), copper (Cu) and zinc (Zn). Plants grown in 5:3:2 (volume/volume) growth media was responded better to the mycorrhizal inoculation than grown in 1:1:1 (v/v) growth media. Funneliformis mosseae inoculated plants have higher plant growth and nutrient uptake than that of Claroideoglomus etunicatum inoculation.  相似文献   

7.
Abstract

The relationship between nutrient uptake and root growth of cotton (Gossypium hirsutum L.) was studied under field conditions. This basic information could be beneficial when making best management decisions concerning the time of application and placement of fertilizer. A field study was conducted in North Alabama on a fertile Dewey silt loam (clayey, kaolinitic, thermic Typic Paleudult). Aboveground whole plants were harvested at approximately 10‐day intervals beginning at 211 cumulative heat units (CHU) after planting (37 days after planting: 4‐true leaves). Root length of harvested plants was also measured by depth and distance from the plant. Maximum root length was obtained at 1174 CHU (117 days after planting), while dry matter continued to increase until a maximum was obtained at 1317 CHU (128 days after planting). Maximum root length density of 1.60 cm cm3 was obtained in the surface 0–15 cm layer in the in‐row position at 912 CHU (99 days after planting). After first bloom approximately 70% of the cotton root system was in the surface 30 cm of soil. Average daily influx of S per m of root length increased with plant age until 1317 CHU (near cut‐out), after which influx declined. Nitrogen (N), calcium (Ca), and iron (Fe) influx peaked very early in the season (291–469 CHU) followed by a general decrease with plant age. Maximum daily influx of potassium (K), phosphorus (P), magnesium (Mg), copper (Cu), manganese (Mn), and zinc (Zn) per meter of root occurred at approximately peak‐bloom (764–912 CHU, 87–99 days after planting) and decreased with plant age. Copper, Fe, Mn, and Zn influx rates were ~ 1000 times lower as compared to the other nutrients.  相似文献   

8.
Beneficial soil bacteria are able to colonize plant root systems promoting plant growth and increasing crop yield and nutrient uptake through a variety of mechanisms. These bacteria can be an alternative to chemical fertilizers without productivity loss. The objectives of this study were to test bacterial inoculants for their ability to promote nutrient uptake and/or plant growth of rice plants subjected to different rates of chemical fertilizer, and to determine whether inoculants could be an alternative to nitrogen fertilizers. To test the interaction between putatively beneficial bacteria and rice plants, field experiments were conducted with two isolates: AC32 (Herbaspirillum sp.) and UR51 (Rhizobium sp.), and different nitrogen fertilization conditions (0%, 50%, and 100% of urea). Satisfactory results were obtained in relation to the nutrient uptake by plants inoculated with both isolates, principally when the recommended amount of nitrogen fertilizer was 50% reduced. These bacterial strains were unable to increase plant growth and grain yield when plants were subjected to the high level of fertilization. This study indicated that the tested inoculant formulations can provide essential nutrients to plants, especially when the levels of nitrogen fertilizers are reduced.  相似文献   

9.
集约化互作体系植物根系高效获取土壤养分的策略与机制   总被引:6,自引:1,他引:5  
【目的】植物根系的形态与生理变化是植物从土壤中高效获取养分资源的重要机制,由相同物种或不同物种组成的互作体系中植物根系对养分的吸收利用受相邻植物竞争的强烈影响,阐明互作体系不同竞争条件下植物根系获取养分的策略并揭示其作用机制,这是基于根系觅食行为探讨养分高效利用的根际调控途径与技术措施的重要理论基础。主要进展根系属性的互补性有利于降低根系间对养分的竞争。根系构型的互补性,例如深根系与浅根系植物互作,促进个体植株对土壤剖面不同深度养分的吸收利用;由根系可塑性介导的水平方向上根系空间分布的互补性,提高了植物根系对同一土层不同空间位点土壤养分的挖掘;个体植株根系形态属性与相邻植物根际生理过程的互补性促进根系对不同形态养分的利用。互作体系根系获取养分的策略具有高度互补性,这有助于提高整个作物系统的养分利用效率,进而提高生产力。根系空间生态位的分离 (包括垂直与水平方向) 以及根际生物化学特征生态位的分离,是驱动互作体系根系高效获取养分资源的主要机制。合理的根层调控可以提高植物根系挖掘土壤养分的能力;优化互作体系物种的搭配能充分发挥根的互作效能,提高养分利用的生物潜力。问题与展望今后应进一步针对集约化高投入作物体系,通过管理根层养分供应和物种间的互作效应,强化根际养分信号的调控作用,调节根系形态与生理特性,降低种间竞争,增强种间互利,以最大化根系和根际的生物学潜力,提高养分利用效率和作物产量,为实现以节肥增效为核心的可持续集约化作物生产提供重要的调控策略与途径。  相似文献   

10.
不同栽植代数杉木林养分循环的比较研究   总被引:15,自引:0,他引:15  
在全国杉木中心产区福建建瓯,选择不同栽植代数的杉木人工林,进行养分循环的比较研究,结果表明,不同栽植代数杉木林的养分循环存在差异。随栽植代数的增加,林分养分的年归还量、年吸收量及归还吸收比均呈递减趋势,表现为1代2代,而营养元素的周转期则呈增加趋势,说明栽植代数对杉木林养分的归还量及吸收量有较大影响,多代连栽不利于杉木林地肥力的恢复。随林分年龄的增加,杉木林养分年积累量呈明显下降趋势,1代成熟林比中龄林下降14.74%,2代成熟林比中龄林下降11.86%;而杉木林养分的年归还量、年吸收量和归还吸收比则随林分年龄的增加呈增加趋势,表现为成熟林中龄林,因此适当延长轮伐期有利于杉木林的养分归还。  相似文献   

11.
To overcome soil nutrient limitation, many plants have developed complex nutrient acquisition strategies including altering root morphology, root hair formation or colonization by arbuscular mycorrhizal fungi (AMF). The interactions of these strategies and their plasticity are, however, affected by soil nutrient status throughout plant growth. Such plasticity is decisive for plant phosphorus (P) acquisition in P‐limited soils. We investigated the P acquisition strategies and their plasticity of two maize genotypes characterized by the presence or absence of root hairs. We hypothesized that in the absence of root hairs plant growth is facilitated by traits with complementary functions, e.g., by higher root mycorrhizal colonization. This dependence on complementary traits will decrease in P fertilized soils. At early growth stages, root hairs are of little benefit for nutrient uptake. Regardless of the presence or absence of root hairs, plants produced average root biomass of 0.14 g per plant and exhibited 23% root mycorrhizal colonization. At later growth stages of maize, contrasting mechanisms with functional complementarity explained similar plant biomass production under P limitation: the presence of root hairs versus higher root mycorrhizal colonization (67%) favored by increased fine root diameter in absence of root hairs. P fertilization decreased the dependence of plant on specific root traits for nutrient acquisition. Through root trait plasticity, plants can minimize trade‐offs for developing and maintaining functional traits, while increasing the benefit in terms of nutrient acquisition and plant growth. The present study highlights the plasticity of functional root traits for efficient nutrient acquisition strategies in agricultural systems with low nutrient availability.  相似文献   

12.
13.
The nutrient uptake and allocation of cucumber (Cucumis sativus L.) seedlings at different root-zone temperatures (RZT) and different concentrations of nitrogen (N), phosphorus (P), and potassium (K) nutrients were examined. Plants were grown in a nutrient solution for 30?d at two root-zone temperatures (a diurnally ?uctuating ambient 10°C-RZT and a constant 20°C-RZT) with the aerial parts of the plants maintained at ambient temperature (10°C–30°C). Based on a Hoagland nutrient solution, seven N, P, and K nutrient concentrations were supplied to the plants at each RZT. Results showed that total plant and shoot dry weights under each nutrient treatment were significantly lower at low root-zone temperature (10°C-RZT) than at elevated root-zone temperature (20°C-RZT). But higher root dry weights were obtained at 10°C-RZT than those at 20°C-RZT. Total plant dry weights at both 10°C-RZT and 20°C-RZT were increased with increased solution N concentration, but showed different responses under P and K treatments. All estimated nutrient concentrations (N, P, and K) and uptake by the plant were obviously influenced by RZT. Low root temperature (10°C-RZT) caused a remarkable reduction in total N, P, and K uptake of shoots in all nutrient treatments, and more nutrients were accumulated in roots at 10°C-RZT than those at 20°C-RZT. N, P, and K uptakes and distribution ratios in shoots were both improved at elevated root-zone temperature (20°C-RZT). N supplies were favorable to P and K uptake at both 10°C-RZT and 20°C-RZT, with no significantly positive correlation between N and P, or N and K uptake. In conclusion, higher RZT was more beneficial to increase of plant biomass and mineral nutrient absorption than was increase of nutrient concentration. Among the three element nutrients, increasing N nutrient concentration in solution promoted better tolerance to low RZT in cucumber seedlings than increasing P and K. In addition, appropriately decreased P concentration favors plant growth.  相似文献   

14.
Mineral nutrients in grains act as a source of nutrients in human diets, in which deficiencies of key minerals including calcium, magnesium, copper, iron, and zinc have prompted efforts to increase their concentrations in the edible portions of staple grain crops. Wheat (Triticum aestivum L.) crops in many regions often suffer abiotic stresses such as drought, extreme heat or frost during grain filling, which affect mineral source–sink relationships. We hypothesized that these stresses would have nutrient‐specific impacts on grain nutrient concentrations due to differences among nutrients in phloem mobility, post‐anthesis uptake and grain loading patterns. Nutrient loading patterns into wheat grains were investigated in two wheat cultivars in the field by sequentially harvesting tagged ears and analyzing tissues for key nutrients. In addition, the impact of perturbed source–sink relations during grain filling on nutrient loading was investigated by inducing post‐anthesis drought /floret abortion in a glasshouse study. Over 90% of Ca and around 70% of Na, K, and Mg accumulated in both wheat cultivars in the field during the first 14 d of grain development. The concentrations of micronutrients (Mn, Fe, Cu and Zn), Mg and P in grains generally increased when florets were aborted, and were unchanged under drought stress, while concentrations of Ca and K were highest under drought stress and lowest under the 66% floret abortion treatment. The observed changes in grain nutrient concentrations from post‐anthesis drought/floret abortion could not be fully explained by nutrient‐specific differences in phloem mobility, post‐anthesis uptake and grain loading patterns. This study will inform future research to define the precise roles of individual nutrients within developing grains and to fully understand the observed variations in grain nutrient concentrations due to source/sink modifications.  相似文献   

15.
The capacity of plant growth-promoting rhizobacteria (PGPR) – Bacillus amyloliquefaciens GB03 (BamGB03), B. megaterium SNji (BmeSNji), and Azospirillum brasilense 65B (Abr65B) – to enhance growth and nutrient uptake in wheat was evaluated under different mineral N fertilizer rates, in sterile and non-sterile soils, and at different developmental stages. In gnotobiotic conditions, the three strains significantly increased plant biomass irrespective of the N rates. Under greenhouse conditions using non-sterile soil, growth promotion was generally highest at a moderate N rate, followed by a full N dose, while no significant effect was observed for the inoculants in the absence of N fertilizer. At 50N, plant biomass was most significantly increased in roots (up to +45% with Abr65B) at stem-elongation stage and in the ears (+19–23% according to the strains) at flowering stages. For some nutrients (N, P, Mn, and Cu), the biomass increases in roots and ears were paralleled with reduced nutrient concentrations in the same organs. Nevertheless, growth stimulation resulted in a higher total nutrient uptake and higher nutrient uptake efficiency. Furthermore, Abr65B and BmeSNji counteracted the reduction of root development caused by a high N supply. Therefore, combining PGPR with a proper cultivated system, N rate, and plant stage could enhance their biostimulant effects.  相似文献   

16.
A new approach for determining optimum nutrient element ratios in plant tissue is presented. Essential steps in the procedure involve: a) measuring patterns of response to pairs of nutrient elements in factorial fertilizer trials, b) modeling the yield response surface using a bivariate, Mitscherlich‐related response function, c) defining balanced nutrition in terms of the parameters of the response surface, d) identifying combinations of P and S fertilizer resulting in balanced nutrition, and e) determining from plant chemical analysis the ratio of nutrients in plant tissue in nutritionally balanced combinations. The approach is illustrated by data from a phosphorus (P) by sulfur (S) factorial field fertilizer trial on a mown mixed white clover (Trifolium repens cv Grasslands Huia) and ryegrass (Lolium perenne L cv Grasslands Nui) sward. Different parameters of yield [total dry matter production, clover dry matter production, clover nitrogen (N) uptake] required different ratios of S:P in fertilizer and consequently in plant tissue for nutritional balance. Also, plant tissue S:P ratios for balanced nutrition declined as the level of nutrition increased. Economic optimum S:P fertilizer ratios were higher than those ratios required for nutrient element balance due to the lower cost and higher effectiveness per kilogram of fertilizer S compared with fertilizer P. Ratios of S and P to N in clover tissue were useful indicators of the adequacy of S and P for clover which was dependent on N2 fixation for its N supply. It is suggested that a nutrient element index system showing both relative and absolute nutrient element status might be built around N as an internal standard for legumes dependent on N2 fixation and possibly also for non‐legumes.  相似文献   

17.
Accumulation of dry matter and plant nutrients by crops over the growing season is important to resource management for agricultural production and for meeting environmental standards. It is becoming more common in agricultural and environmental management to use mathematical models to describe such systems. In this article, an extended probability model was used to characterize accumulation of dry matter and plant nutrient uptake, both of which exhibited sigmoid behavior with time. Data from field studies included corn (Zea mays L.), tobacco (Nicotiana tabacum), and soybean (Glycine max). For the case of corn, it was shown that maximum total plant dry matter at maturity agreed very closely for the three sites. The ratio of the paramters mean time to standard deviation of the distribution was very similar for dry matter and plant nutrient accumulations, with an average of 3.6 for Wooster, OH and 3.5 for Clayton, NC. The ratio was 4.3 for water reuse at Tallahassee, FL. For tobacco, the ratio was also very similar for dry matter and plant nitrogen (N) and potassium (K), and was 3.2 at Raleigh, NC. The ratio was 2.9 for leaf area of soybeans grown at Gainesville, FL. Data for dry matter and plant nutrient accumulation followed the sigmoid shape of the model rather well. The model also produced the “hump”; often observed in plant nutrient concentration during early stages of growth. The probability model suggests that for the crops studied, growth rate followed a gaussian distribution over the season, at least to first approximation.  相似文献   

18.
19.
栽培模式对直播油菜生长、产量和养分吸收利用的影响   总被引:5,自引:2,他引:3  
发展直播油菜对增加我国油菜种植面积和总产有重要意义,但栽培措施尤其是施肥技术的滞后极大地影响了油菜的产量及施肥效果。2009/2010年度在湖北省油菜主产区设置田间试验,研究栽培模式对直播油菜生长、产量、经济效益和养分吸收利用的影响,探讨适合当前生产的高产高效栽培技术。结果表明,各优化模式比农民习惯栽培模式均有增产增收效果,其中在30104 plant/hm2种植密度、秸秆还田和加强病虫草害防治的基础上进行优化施肥(氮、磷、钾肥用量分别为N 195 kg/hm2、 P2O5 90 kg/hm2、K2O 90 kg/hm2,硼砂用量15 kg/hm2,氮肥和钾肥分次施用)的模式Ⅲ表现最好,比农民习惯施肥增产35.9 %、增收1632 Yuan/hm2,地上部干物质量和养分累积也均较高,氮、钾肥偏生产力分别为N 13.7 kg/kg和K2O 29.8 kg/kg,实现高产高效目标。说明当前直播油菜的栽培模式应结合其生长发育进程和养分吸收规律,适当密植以增库促源,加强植保防治病虫草害,更重要的是积极推行平衡施肥和有机、无机配施,并合理安排施肥时期及比例。  相似文献   

20.
Study aims to investigate the effects of vermicomposts containing oil processing wastes, dairy manure, municipal open market wastes and straw on the growth, nutrient concentrations and nutrient uptakes of corn plant. For this, there different mixtures were prepared. Vermicomposts were applied with the rates of 0, 5000, 10000, and 20000 kg ha?1 to 2 kg soil containing pots. Study was conducted in growth chamber for 2 months. Vermicompost applications increased plant growth, some plant nutrient concentrations and uptake. Also, vermicomposts showed the variation on parameters depending on their mixtures. Results showed that nutrients taken by the plant increased with the vermicompost until 10000 kg ha?1 dose. Most of the nutrient concentrations such as phosphorus, potassium, calcium, magnesium, iron, and manganese (P, K, Ca, Mg, Fe, and Mn) were not increased in plant tissues, whereas uptake of them by the plant showed a significant increase. In addition, residual soil nutrients increased with the increase in vermicompost levels.  相似文献   

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