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1.
Abstract

Composts may be incorporated into container mixes for several purposes, including to supply nutrients, add organic matter, or suppress plant diseases. The objective of this research was to assess the nutritional benefits of two composts derived in common from composted chicken manure and used in formulation of container media for growth of tomato (Lycopersicon esculentum Mill.). The composts differed in extractable and total plant nutrients so that one of the composts was considered a nutrient‐rich material and the other a nutrient‐poor material. Media were formulated from soil or peat with the composts added in a progressive array of concentrations from a medium with no compost addition to a medium that was all compost. Half of the media were treated with a water‐soluble, complete fertilizer and half were left unfertilized. Optimum growth occurred in media in which compost did not exceed 25% of the volume. The beneficial effects of the composts on plant growth were associated with increased supply of nutrients for the plants. The suppressive effects were attributed to restricted accumulation of nutrients with the nutrient‐poor compost and to excessive potassium supply and accumulation with the nutrient‐rich compost. Fertilization was beneficial in increasing plant growth with the nutrient‐rich compost and was essential for plant growth with the nutrient‐poor compost. The research demonstrated that composts can be used in formulation of media for container growth of plants.  相似文献   

2.
Physical and chemical properties of container media are important factors in controlling the supply and movement of water and nutrients for nursery plant growth. The objectives of this study were to evaluate the physical and chemical properties and quality of media formulated with systematic substitution of composted pine bark (bark) for sphagnum peat (peat) in the presence of sand. Ten formulations were prepared that contained 40-90% bark, 0-50% peat, and 10 or 20% sand by volume. Increasing the percentage of bark increased the percentage of coarse particles, and linearly decreased the medium-sized particles in media in either 10% or 20% sand. Increasing the percentage of bark in the media significantly decreased water holding capacity, whereas bulk and particle densities and total porosity were influenced by the interaction of bark x peat x sand. Increasing the percentage of bark increased electrical conductivity and total C, P, K, Ca, Fe, Cu and Zn. Availability of nutrients were also increased by increasing percentages of bark. Substitution of bark for peat did not influence the pH of the formulated media. Our results suggest that formulated media with 70 to 80% composted pine bark and 10 to 20% peat (V/V) exhibited physical and chemical properties considered optimum for the growth of container nursery plant crops.  相似文献   

3.
Abstract

A mathematical equation predicting cation exchange capacity (CEC) of pine bark‐sand container media from CEC of the individual components was formulated. The equation is the weighted sum of milliequivalents contributed by each component and is corrected for shrinkage due to mixing of components. Both measured and predicted CEC increased linearly with increasing percent volumetric bark in pine bark‐sand media. Regression equations describing measured and predicted CEC were not statistically different. The predictive equation was also tested on 6 non‐synthesized 2‐component media prepared from peat moss, perlite, pine bark, vermiculite, and sand. No statistical differences between measured and predicted CEC were obtained.  相似文献   

4.
膜材料及其构成对调节控释肥料养分释放特性的影响   总被引：18，自引：3，他引：18  
试验采用水溶出率实测法研究了自行研制的控释肥料养分释放的特性。以养分释放速率和释放期为主要指标评价了膜材料及其构成对调节控释肥养分释放特性的影响。结果表明,膜材料M2的控释性能优于膜材料M1;用膜材料M1包膜肥料的养分累积释放曲线呈对数曲线,而用膜材料M2包膜肥料的养分累积释放曲线呈直线型。在膜的比面重(单位肥料面积上所含膜材料的重量)为20～80g/m2范围内,随着比面重的增加,包膜肥的初期溶出率降低,释放期延长;通过调节膜材料组成与比面重可以研制出释放期不同的控释肥料。  相似文献   

5.
Abstract

The dry matter yield and nitrogen content of marigold (Tagestes erecta), petunia (Petunia hybrida nana compacta) and forget‐me‐not (Myosotis alpestris) plants growing in a range of peat‐based container media amended with different proportions of either sand, perlite, pumice, sawdust, bark chips or soil were studied under glasshouse nursery conditions.

Plant responses differed between species as manifested by their different correlations with measured moisture and aeration characteristics of the media. Marigold and petunia were adversely affected by excessive moisture content as demonstrated by their negative correlation with micropore water and container capacity. However, forget‐me‐not, being adapted to relatively high moisture regimes, responded adversely to increased aeration.  相似文献   

6.
Ammonium sulfate or urea were added as N-source to shredded straw of Miscanthus ogiformis ‘Giganteus’ and water was included as control. The combined materials were composted for seven months, and the resulting composts were tested as growth substrates for nursery container plants and compared with fertilized and unfertilized peat substrates. The pH was below recommended level for the compost substrate made with ammonium sulfate and for the unfertilized peat substrate throughout the experiment. Electrical conductivity and concentrations of most nutrients were low and decreased throughout the experiment for all growth substrates. Shrinking of the growth substrates after 4, 12 or 17 months was larger for compost substrates than for peat substrates. Bulk density increased in compost substrates and decreased in peat substrates, while the total loss of C was greater in compost substrates than in peat. Water retention was lower and air volume greater for compost substrate made with ammonium sulfate than for fertilized peat. Algae and mosses did not occur on Miscanthus compost growth substrates in contrast to peat substrates. The shoot length and dry matter of Hedera helix, produced after four and 12 months of growth, and five months following cut back, showed that plants can grow well in compost substrates made of Miscanthus straw and ammonium sulfate or urea. However, the compost substrates could not fully substitute for fertilized or unfertilized peat substrate with respect to dry matter production.  相似文献   

7.
控/缓释肥在不同介质中的氮素释放特性及其肥效评价   总被引：45，自引：4，他引：45  
以水、土壤、砂子、土壤+砂子和土壤+沸石为介质,研究了5种控/缓释肥的溶(淋)出特征。结果表明,由于性质不同,同一肥料在不同介质中的溶(淋)出率和溶(淋)出模式有很大差异。水中溶出率虽可以快速比较不同控/缓释肥的溶出速率,但用以估测肥料在田间的实际肥效,则产生较大的误差。客观、合理地评价控/缓释肥,应该在肥料 土壤 作物系统中考虑。相对而言,考虑土壤因子的土柱淋出率法较水中溶出率法更为接近田间实际。  相似文献   

8.
Abstract

Plant derived bio-based materials are environmental-friendly and provide a cheap and an attractive source for synthesis of controlled release urea fertilizers which have positive impact on plants’ health. In this work, application of rosin-maleic anhydride adduct encapsulated controlled release micro urea fertilizer (RA-mCRUF) was investigated for the optimization of its controlled urea release properties and evaluation of growth promoting effect on maize (Zea mays) plant under three different soil texture classes. Through response surface methodology, the independent response variables, were optimized for controlled release response of urea. Study found optimized coating repeats, 5.00 cycles; drying time, 11.71?h; and particle size, 41.82?µm; at urea release response of 331.62?mg L?1 in distilled water. Optical microscopy images further demonstrated a more compact and homogeneous surface of RA-mCRUF without any coating defects. Besides, RA-mCRUF predicted a better growth performance of maize plant in clay loam soil. Moreover, RA-mCRUF treated maize plant showed 9.0–24.5?mg g?1 increase in chlorophyll contents and 7.44–12.75?g rise in plant dry biomass. This work successfully produced a new type of RA-mCRUF which has applied role in soil nutrients conservation and addressing effectively food security through crops protection.  相似文献   

9.
As limited information is available on the nutrition of freesias an experiment was carried out to examine the influence of nutrients on foliage and corm growth, and flowering of container‐grown plants. The experiment ran for 10 months using seedlings grown in a peat:sand (3:1,v:v) medium with combinations of varying levels of nitrogen (N), phosphorus (P), potassium (K), and lime. Nitrogen fertilization had a significant effect on many aspects of flowering and growth while the response to P was similar except for a lack of influence on spike production. Fertilization of 600–800 g N m‐3 and at least 200 g P m‐3 are recommended for strong leaf and corm growth with good flowering. There were few significant responses to added K, except in early foliage growth, while liming increased foliage development. High flowering, leaf, and corm growth should be achieved with a media pH of 5.9 and foliar nutrients of 2.2–2.3% N, 0.25–0.30% P, 4.0–4.5% K, 0.65–0.80% calcium (Ca) and 0.20–0.25% magnesium (Mg).  相似文献   

10.
Abstract

Following observation of severe chlorosis and dieback of meri‐stem tissue in asparagus seedlings started in the greenhouse in a soilless media, a study was conducted to determine if the growth patterns were associated with one or more of the media components. Asparagus seedling growth using several potting media was compared. Treatments included single component media, washed sand, perlite, peat, Plainfield loamy sand [a local soil (PLS)], plus 1: 1 mixtures of peat/perlite, washed sand/peat, PLS/perlite, washed sand/peat, and PLS/peat. Abnormal growth patterns were observed in several of the media. Chlorosis was associated with high pH which occurred in perlite, washed sand, and their combinations. Chlorotic plants were characterized by low root and fern dry weights and low fern to root ratios. Meristem dieback occurred in several media treatments and did not appear to be pH related. Plants exhibiting dieback had fern to root ratios approaching 1 if they were not also affected by chlorosis. Nutrient availability was suspected to be a cause but this hypothesis was not substantiated by data collected in this experiment. Asparagus growth in a mixture of Plainfield loamy sand and peat was the highest and was similar to that of field grown seedlings.  相似文献   

11.
Abstract

Regression analyses were used to survey the effects of extractable NO3‐N, P, K, Ca, Mg, and soil pH on electrical conductivity (EC) in a 1: 1: 1 (v/v/v) peat‐sand‐perlite azalea (Rhododendron sp.) growing medium amended with soluble 21–3–6 (N‐P‐K) or slow‐release 18–3–6 fertilizer sources. Simple linear correlations indicated a high degree of relationship between NO3‐N, P, and K versus EC (r=0.95**, 0.79**, and 0.79**, respectively). Partial regression coefficients suggested that NO.‐N was the primary ionic species affecting EC. The correlations between EC versus P and K were apparently related to their intercorrelation with NO3 ‐N, associated with the use of N‐P‐K fertilizers. These relationships were constant across fertilizer sources. The results demonstrate a potential for the use of soil EC in the estimation of NO3‐N in soilless rooting media.  相似文献   

12.
Abstract

Philadelphus mexicanus, Cuphea hyssopifolium ’Violet’ and Viola wittrockiana ’Blue Angel’ (pansy) were grown in mixtures of peat and Pinus radiata bark with Nitrogen Drawdown Index (NDI75) values ranging from 1.1 to 0 (NDI150 value of 0.36). Nutrients were provided via liquid feeds containing 150–700 mg/L N or via coated fertilizers added at 3–9 g/L medium. Growth responses covered the full spectrum from N deficiency to growth reduction through excessive salinity. Some of the controlled‐release fertilizers used released nutrients at considerably higher rates than that nominated by the manufacturer.

At the lowest levels of N application, growth generally graded down from a maximum in medium with the highest NDI value to a minimum in medium with the lowest NDI value. Calculations based on growth response indicated that N immobilisation was at a weekly rate of 1.5 to 2.9 mg/L for each 0.1 NDI unit fall below 1, with a mean of about 2.5 mg/L.  相似文献   

13.
Abstract

Copper (Cu) can be toxic to creeping bentgrass (Agrostis palustris ’Penncross') grown in sand‐based systems. Plant analysis is not always a reliable predictor of toxic levels of Cu in these sand‐based systems. Therefore, there is need for soil analysis to detect potentially toxic Cu concentrations in soil. The objective of this research was to determine the effectiveness of AB‐DTPA and Mehlich III soil tests to assess Cu availability to ‘Penncross’ creeping bentgrass grown in calcareous and silica sand/peat media. Samples of sand/ peat were removed from greenhouse pots, air dried, and Cu was analyzed by inductively coupled argon plasma spectrometry (ICAP/IRIS). Correlations were made between extracted Cu and Cu in the shoot and root tissue of the plant. The AB‐DTPA‐extractable Cu was 24% and 42% higher for the calcareous sand at the 400 and 600 mg kg‐1 Cu treatments, respectively, when compared with Cu extracted from the silica sand. The Mehlich III soil test extracted 25% more Cu at the 400 mg kg‐1 Cu treatment and 37% more Cu at the 600 mg kg‐1 Cu treatment from the calcareous as compared to the silica medium. Shoot and root tissue Cu concentrations were higher at all Cu treatment levels for plants grown in silica sand. Although correlations were significant between Cu extracted from both sands by the AB‐DTPA and Mehlich III soil tests and Cu in the shoot and root tissue of plants, these extractants were unsuccessful in determining Cu availability from the two sand medium. This research indicates a need for a soil test which can be effectively used to extract plant‐available Cu from sand‐based systems.  相似文献   

14.
该文提出了可应用于农田的肥料控释装置方案设计,此装置由肥料主管道和养分释放分管道组成,选取天然、半天然高分子材料壳聚糖和果胶作为释放分管道的胶粘物质,在实验室条件下检测了其控释效果,结果表明:养分主要呈线性释放,装置具有良好控释效果.利用Fick第一扩散定律和欧姆定律模拟了装置养分的释放,结果表明:养分的释放主要受扩散系数或物阻率、扩散面积、胶粘物质厚度等因素影响.该模型表明,养分是呈线性释放的,和实测结果相一致,并由此计算出了胶粘物质的控释参数:扩散系数或物阻率,为实际应用提供了理论基础.  相似文献   

15.
Abstract

Laboratory incubation experiments designed to measure potential rates of decomposition and N mineralization from plant residues typically use either sand or soil as a base medium for incorporation of the materials. Few studies have addressed the effects of base media on decomposition and N mineralization, or the interaction between media and incubated materials. This experiment compared the decomposition and net N mineralization rates of four plant residues incubated in the laboratory in both sand and soil base media. Initially, CO2‐C evolution was greater from residues incubated in die soil, while net N mineralization was greater with the residues in sand. After 11 weeks, cumulative net N and C mineralized from residues incubated in either medium were more similar, but differences between media were still present. The form of N recovered differed between the media, with nitrification absent or occurring at a low rate in the sand. Differences in the rate and extent of decomposition and net N mineralization from plant materials were evident. These differences could influence the interpretation of results from this type of experiment.  相似文献   

16.
Abstract

Uses of lime‐stabilized biosolids in container media or topsoil formulations may be limited by alkalinity imparted by lime added for reductions in vector attraction and pathogens and for suppression of odors. This experiment was conducted to assess the suitability of quicklime‐stabilized biosolids mixed with calcareous or noncalcareous sand and with sulfur or aluminum sulfate as acidifying agents for development of synthetic topsoil for turfgrass (Lolium perenne L.) production. Grass emergence and growth were inhibited in media that were not amended with an acidifying agent. Additions of aluminum sulfate were more effective in acidification than sulfur, causing an immediate drop in pH, whereas additions of sulfur required about 2 months for a depression in media pH. With time, electrical conductivities were higher in media with additions of sulfur than in media with additions of aluminum sulfate. Calcareous sand mixed with biosolids (2 sand: 1 biosolid, v: v) gave a better medium for growth of turfgrass than noncalcareous sand mixed with biosolids. Calcareous sand flocculated biosolids, whereas noncalcareous sand dispersed them. Results suggest that calcareous sand and aluminum sulfate are effective agents for diluting and acidifying biosolids for development of a suitable topsoil medium for turfgrass production.  相似文献   

17.
Lingonberry (Vaccinium vitis‐idaea L.) cvs “Sussi”; and “Sanna”; were cultivated on mineral soil with four different soil surface treatments (Sphagnum peat mulch, sand mulch, plastic mulch and herbicide 3‐syclohexyl‐5, 6‐trimethylenurasil (lenasil)). Amount of annual weeds, plant coverage and yield were observed over five years. Weeds were most abundant in the first two observation years. Sand mulch was the least efficient for the control of annual weeds for both cultivars, whereas lenasil was the most efficient for “Sussi”;, and peat mulch for “Sanna”;. The plant coverage increased steadily throughout the years in the “Sussi”; plots, especially in plots mulched with peat. The spreading of “Sanna”; was slower in all treatments. It was best in plots mulched with peat or sand. Overall, “Sanna”; was more productive, with the highest yield on sand mulch and the lowest on lenasil‐treated plots. “Sussi”;, instead, yielded best on lenasil plots and poorest on sand.  相似文献   

18.
不同无机矿物应用于包膜复合肥的氮素释放特征及其评价   总被引：3，自引：1，他引：2  
探讨了不同无机矿物用于膜材料后的包膜复合肥氮素养分释放特性、生物效应和评价方法。采用了土壤淋溶和土壤盆栽试验两种方法。试验方法的不同造成土壤盆栽与淋溶试验中各处理养分释放拟合曲线的差异 。两种方法的试验结果都能说明:无机矿物材料能有效地保持Ｎ素养分较长时间处于NH4＋-N形态,减少了因转化为NO3－-N形态造成的养分淋溶损失,但是各种材料彼此间存在一定的差异。盆栽试验中养分累计释放量与释放速率虽然快于作物的生理需求,但是受矿物材料和土壤缓冲作用的影响,作物氮素供应状况良好。与普通复合肥相比,各无机矿物用于包膜肥后能显著提高氮素利用率。蒙脱土效果最好,其次为高岭土,且差异显著。滑石粉、硅粉、硅藻土与前两者相比效果稍差,差异显著,但三者间差异不显著。无机矿物材料的耐水程度,养分吸附、固定能力和离子交换量等理化性质会影响包膜肥的养分释放性能。对于膜层疏松、耐水性差、主要靠养分吸附和固定机理控释的包膜肥来说,采用土壤作为养分释放介质更接近真实释放性能。评价包膜肥料的性能应该充分考虑养分形态、膜材特性、包膜工艺、土壤环境、供试作物等各方面因素,重点在“肥料–土壤–作物”系统中考查,从多种角度制定不同方案、通过多种方法综合评价其缓释效果。  相似文献   

19.
In recent years, innovations in fertilizer research have principally been in the design of products to supply more timely plant nutrients and mitigate detrimental losses to the environment. In the development of these fertilizers, a laboratory method to comparatively screen a large number of formulations for the rate of nutrient release is a critical first step in formulation optimization to significantly reduce time spent on pot and field trials, reducing costs considerably. Currently, given the absence of a standard laboratory method for all fertilizers, adaptions of a method for coated fertilizers from the International Organization for Standardization (2017) ISO 21263 and other column tests are being used which are often complex and/or require manual sampling which can be laborious, time consuming and costly. The method presented here evaluates the dynamic release in real time by continuously perfusing samples in columns utilizing an automated sample accumulation system for short‐term and long‐term release studies and eliminates the need for soil/sand packing of columns. Mass balance is accounted for by analysing the residue after dissolution and the amount released is expressed as a % of the total nutrient content in the product. This method is reliable, uncomplicated and cost‐effective and has been used to test uncoated soluble fertilizers, nanofertilizers, fertilizers with newly developed coating technologies and other slowly soluble fertilizers, to assess the effect of variables like coating chemistry and thickness, fertilizer composition or fertilizer particle size on release rate.  相似文献   

20.
Coleus (Plectranthus barbatus Andr.) is a medicinal herb whose roots contain forskolin. Incidences of soil-borne diseases, wilt complex and nematodes are the major limiting factors for growing this crop under soil media. Hence, an investigation was initiated for the standardization of soilless growth media and nutrient solution concentration in coleus. Coco peat, vermiculite, sand and their combinations were used as potting media with different concentrations of nutrients based on the recommended dose of fertilizers for soil media (1,080 mg plant?1 nitrogen, 960 mg plant?1 phosphorous and 1200 mg plant?1 potassium). Among the different media and nutrients, plants grown under coco peat media with 80% of the recommended dose of fertilizer for soil (864 mg plant?1 nitrogen, 768 mg plant?1 phosphorous and 960 mg plant?1 potassium) recorded significantly higher root yield (17.10 tha?1) and quality parameters (0.98% forskolin). Benefit–cost ratio was also recorded maximum (4.25) in the same treatment.  相似文献   

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