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1.
Abstract

Soft winter wheat is used to make cookies, cakes, crackers, donuts, etc., and as such, grain nitrogen content (as protein) is an important determinant of flour quality and eventually the quality of the products made from it. Intensive Cereal Management (ICM) techniques are being adapted throughout the midwestem United States to increase grain yield and crop profits. The effect of additional/altered management inputs on grain nutrient content is important since they may be detrimental to subsequent product quality. The objective of this study was to determine the effects of cultivars and ICM inputs on grain nutrient content Identical field studies were conducted in 1985 and 1986 at Columbus, OH, East Lansing, MI, and Madison, WI containing three cultivars subjected to each of three management treatments differing in seeding and nitrogen rates, and the use of a fungicide, Propiconazole (Tilt) and plant growth regulator, Ethephon (Cerone). Nitrogen in the form of urea was applied at specific growth stages, and rates adapted to the soil type and previous crop of each study location so that similar amounts of N would be available to the wheat crop at each location.

Both environment and cultivar had significant effects on the leaf content of some but not all nutrients. The combination of increased seeding and nitrogen rates had no effect on grain yield but increased grain nitrogen content, leaf N, Ca, Mg, Mn, and Fe content The use of Tilt and Cerone also increased grain yield and nitrogen content, but lowered leaf K, Ca, and Mg.  相似文献   

2.
Abstract

In this study, the effect of increased soil moisture on the nutritional status of two key commercial avocado (Persea americana Μill.) cultivars, ‘Fuerte’ and ‘Hass’, was examined. The results revealed that prolonged exposure of plants to high soil water content conditions (waterlogging) reduced the total nutrient content (absolute quantity) of almost all of the nutrients in scion’s tissues (leaves and stems) of both cultivars. The decrease of nutrient content in the ‘Fuerte’ leaves was more prominent/severe compared to the ‘Hass’ leaves, which could be the outcome of the reported higher sensitivity of the cultivar to soil waterlogged conditions in previous studies. Interestingly, the inability of ‘Fuerte’ avocado plants to withstand high soil moisture conditions was not reflected in the relative concentrations of most nutrients, both in leaves and stems. Indeed, significantly higher concentrations of P, K, B, Fe, and Zn were found in the leaves of ‘Fuerte’ waterlogged plants than in well-watered ones. This fact reveals that under marginal/stressful conditions, like waterlogging, nutrient concentration in tissues does not reflect potential negative effects on total nutrient uptake of avocado plants, obviously due to concentrated nutrient phenomena primarily created by the stress-dependent growth inhibition. Therefore, total nutrient content is proposed as a more representative indicator for assessing plant response to waterlogged conditions.  相似文献   

3.
Field experiments were conducted on cotton to evaluate the different cotton-based intercropping system along with balanced nutrient management practices on enhancing cotton productivity. Cropping systems have been considered as main plots and nutrient management practices have been considered as subplots. The results showed that cotton + onion system recorded the highest cotton equivalent yield (CEY) of 2052 and 1895 kg ha?1 which was on par with cotton intercropped with dhaincha, which recorded 2010 and 1894 kg of CEY ha?1 in both the seasons. Combined application of 100% recommended NPK with bioinoculants (S5) registered highest CEY in both the seasons. Cotton intercropped with dhaincha (M2) recorded highest uptake of N, P, and K. Among the nutrient management practices, application of 100% recommended NPK with bioinoculants (S5) showed highest uptake of N, P, and K. A similar trend was noticed in the post-harvest soil fertility too and it is significantly higher under cotton + dhaincha and application of 100% recommended NPK with bioinoculants treatment compared to 100% recommend NPK alone. It could be concluded from these results that crop productivity can be improved and soil fertility status can be sustained with integrated plant nutrient management practices.  相似文献   

4.
Abstract

Organic farming practices have been reported to reduce agricultural pollution and improve yield and quality compared to conventional practices. Frequently, research has involved comparing completely conventional and organic farming systems over many years. This study was conducted to test whether the use of organic fertilizers versus synthetic fertilizers improved soil fertility and sweet corn (Zea mays L. var rugosa Bonaf.) vigor, yield, size, and nutrient content and minimized nitrate (NO3) leaching and runoff after a single growing season. Sweet corn vigor, yield, and nutrient content were superior for synthetically fertilized sweet corn compared to organically fertilized corn. Runoff NO3 levels were similar regardless of fertilizer type. The use of organic fertilizers neither improved crop yield and quality nor reduced NO3 loss after a single season. These findings are consistent with previous research that reports that more than a single season of organic management is needed to improve soil properties and increase yields.  相似文献   

5.
ABSTRACT

Improving the production of crops is always a concern in the plantation sector since higher production leads to the economic growth of a country. For developing countries, including Malaysia, one of their incomes is crop production. Focusing on crop nutrients supply using fertilizers to increase the production of the crops is better than expanding the plantation areas. The limited knowledge regarding the appropriate nutrients supply and the relation between the nutrients in Malaysia has caused the yield of the crops not meet expectations. Thus, sharing knowledge about the nutrient requirements and the nutrient availability toward the uptake rate of the plants are required. Hence, this work reviews the nutrient supply, the effect of each nutrient on the crop, and the nutrient availability in Malaysia’s plantation. A better understanding of the nutrient requirement to sustain crop health helps to improve the quality of the crop, its yield, and soil performance for future agriculture work. Moreover, this work also discusses the impact of fertilizer on the plantation and different types of fertilizer. Additionally, their nutrient release patterns will be discussed, along with the pros and cons of these existing fertilizers.

Abbreviations: ATP: Adenosine Triphosphate; SRF: Slow-release fertilizers; CRF: Controlled release fertilizer; SCU: Sulfur-coated urea fertilizer; PCU: Polymer-coated urea fertilizer; SRB: Slow release blending fertilizer; NUE: Nitrogen-use efficiency; AV: Ammonia volatilization; CRNF: Controlled release nitrogen fertilizer  相似文献   

6.
作物有效营养面积及最佳营养面积研究   总被引:3,自引:0,他引:3  
韩秉进 《土壤通报》2002,33(1):66-70
通过无肥区和施肥区不同土壤营养面积的试验得出 :黑土垄作区甜菜的有效营养面积是 3 7.8~ 5 3 .4× 67cm ;最佳营养面积是 2 7.3~ 2 9.7× 67cm。无肥区植株有较小的有效营养面积和最佳营养面积 ,施肥区植株有较大的有效营养面积和最佳营养面积。土壤营养面积过小 ,个体生长影响较大 ,会改变其生物学生长规律 ,S型生长曲线不明显  相似文献   

7.
In Hungary, maize is grown on 1 million ha and occupies more than 20% of the arable land. The rich assortment of maize cultivars of different vegetation periods and different responses to nutritional effects, water supply etc. gives the growers the possibility to choose the cultivars suiting best the site characteristics (Jolânkai et al. 1999). Among the cereals maize has the highest genetical potential. To utilize its yield and quality potential, soil types of high nutrient content and regular nutrient supply are required (Gyõrffy, 1979). Both over‐ and under‐fertilization have an unfavourable effect on the yield and quality of maize (Debreczeni, 1985). Crops can be supplied with the appropriate nutrient amounts only with the knowledge of soil characteristics in the different agro‐ecological regions (nutrient content, water supply, soil compactness, pH, nutrient supplying capacity etc.). In Hungary, a network of long‐term field fertilization trials with uniform fertilizer treatments has been maintained at nine experimental sites representing different agro‐ecological regions of the country. This experimental network gives a basis to test the nutrient responses of our main crops and calibrate their optimal nutrient supply (Kismányoky, 1991).  相似文献   

8.
ABSTRACT

Avocado crop is very sensitive to root asphyxiation. Among the agricultural management techniques, soil applications of humic and sulfuric acids became increasingly popular. In a trial with potted 'Hass' avocado trees grown on a silty-clay soil, different soil treatments were applied to determine their effects on tree physiology and soil characteristics: Control, deionized water; SA, H2SO4 application; HA, humic acid application; SA+HA, combination of both treatments. Treatments were applied during a 9-month period. SA reduced soil pH, rised electrical conductivity and reduced saturated soil hydraulic conductivity (Ks) in the upper layers of the potted soil. On the other hand, HA increased electrical conductivity and Ks compared with Control. None of the treatments improved CO2 assimilation, stomatal conductance, stem water potential, chlorophyll fluorescence, growth or nutrient content. Our findings suggest that a rapid and positive response to the application of acids is unlikely to be observed under conditions of restricted oxygen in the root zone.  相似文献   

9.
The vine-growing region of Lumbarda, located in the southeastern part of the island of Korcula, Croatia, has deep sandy soils (paleodunes) associated with the Mediterranean climate and provides optimal conditions for cultivating the autochthonous vine variety Vitis vinifera L. cv. Grk. Unfortunately, recently growers have noted declining yield and quality of grapes resulting from inadequate vineyard management (particularly unsustainable management of soil organic matter) and the occurrence of viral diseases. To revitalize and maintain the vineyards in the Lumbarda region, a detailed study was carried out involving intensive soil survey, analysis of grapevine nutrient status, positive clonal selection, and establishment of new vineyards with virus-free plant material. Preliminary soil survey results provided insight into the extent of variability in major physical and chemical soil characteristics. Based on these results, eight markedly different vineyards were selected for detailed analysis of grapevine nutrients [boron (B), calcium (Ca), copper (Cu), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), phosphorus (P), and zinc (Zn)] at key development stages to detect potential imbalances that may hamper vine growth and affect its production. Leaf blades and petioles were sampled at midflowering and midveraison stages during the 2007–8 growing season from each of the selected vineyards. The greatest variability in nutrient content between the study sites was recorded for Cu, and considerable variability was also determined for B, Mn, Mg, and P. Differences in fertilization practices are the most common reasons for this variability. The results point to B deficiency in some of the vineyards and suggest potentially toxic levels of Cu in others.  相似文献   

10.
Mineral‐nutrient stress is one of the main factors limiting crop production, especially in arid lands. The mineral requirement of a crop is difficult to determine, and the interpretation of foliar chemistry composition is not easy. This study was conducted to compute the minimum yield target for fresh fruit of yellow pepper (Capsicum annuum L.) and the corresponding Compositional Nutrient Diagnosis (CND) as well as to identify significant nutrient interactions of this crop in desert calcareous soils. Preliminary CND norms were developed using a cumulative variance‐ratio function and the chi‐square distribution function. From a small database, we computed means and standard deviations of row‐centered log ratios, VX, of five nutrients (N, P, K, Ca, and Mg) and a filling value, R, which comprises all nutrients not chemically analyzed and quantified them in 54 foliar samples of the popular yellow pepper cv. ‘Santa Fé’. This cultivar is widely grown in northwest Mexico under arid conditions. These norms are associated to fresh fruit yields higher than 15.04 t ha–1. Principal‐component analyses, performed using estimated CND nutrient indexes, allowed us to identify four interactions: negative P‐Ca, P‐Mg, and N‐K, and positive Ca‐Mg. Pepper plants growing on calcareous soils tend to take up more Ca and Mg than considered as optimum in other soil conditions.  相似文献   

11.
Conservation agriculture (CA) has the potential to sustain soil productivity and benefit agroecosystems, yet it is not fully understood how yield responses of different cropping systems are affected by inherent soil characteristics, for example, texture and dynamic soil properties, such as aggregation, nutrients and erosion. In this study, we conducted a systematic review to compare crop yield from cropland with conventional management versus different CA practices, specifically reduced- or no-tillage, agroforestry, organic farming and cover crops. The data were first analysed for different climatic regions, soil textures and cash crop types. We then quantified how yield responses correlated with soil properties change under different CA practices. The results showed that CA practices were associated with an overall mean crop yield increase of 12%. This response was primarily driven by corn, which had a mean yield increase of almost 41% after CA implementation, whereas other cash crops did not have significant yield responses or showed slight decreases, as rotation with mixtures of multiple cash crops had a mean decrease of 6% when using CA. The increase in corn yield after CA may be related to the enhanced ability of that crop to absorb nutrient elements (e.g. nitrogen) and reduce nutrient leaching. Agroforestry increased crop yield by 66% and cover cropping increased yield by 11%, likely due to increases in soil water content and nutrient availability and decreases in erosion and surface runoff. However, other agricultural systems showed no significant increase after CA compared with conventional row cropping practices. Using CA practices had the greatest yield benefit in tropical climates and when farming in coarse-textured soils. In addition, legumes and grass-legume mixtures resulted in significant cash crop yield increases, possibly because legumes promoted the increase of soil nitrogen and depleted soil moisture less compared with other cover crops. The results provide new insight into how interactions between soil properties and CA practices affect crop yield and at the same time can help guide the development of practical, evidence-based guidelines for using conservation practices to improve yield in corn and other cash crops.  相似文献   

12.
A field experiment was conducted to study the combined effect of nutrient and pest managements on soil biomass phospholipid contents,functional biodiversity and substrate utilization patterns of soil microbial populations in hybrid rice cropping system. The mineral N,P and K fertilizers (as urea,calcium superphosphate and KCl respectively) were incorporated at 100,25,and 100 kg ha^-1,respectively, and the various pesticides were applied at the recommented rates. The results of the experiment demonstrated a decline in the microbial abundance and soil microbial biomass phospholipid contents with the advancement of crop growth, and significant changes in substrate utilization pattern of soil microbial population studied were observed with different management practices and at different growth stages. The principal component analysis (PCA) using all 95-carbon sources (BIOLOG plates) gave good differentiation among the treatments, indicating that they have different patterns of carbon utilization under different habitats. The data showed that diversity in microbial community continuously changed with the progression in crop stage,particularly at physiological maturity (PM) stage that was evident from the utilization of different carbon sources at various crop stages.  相似文献   

13.
Abstract

Sustainable production in the Everglades Agricultural Area (EAA) is confounded by decreasing soil depth and high annual rainfall. Formerly a sawgrass marsh, Histosols predominate much of the EAA and these soils have frequently flooded following their drainage in the early 20th century. Subsidence has increased inundation frequency as soil depth has decreased to less than 25?cm in many locations. A 2-year lysimeter study was conducted to examine alternative management practices for improved agricultural sustainability given frequent flooding and reduced oxidation rates on Histosols. Specific management factors examined included water-table, soil depth, and nitrogen (N) fertilizer effects on sugarcane leaf nutrient concentrations and soil nutrient cycling. The trial utilized soil depths of 13 and 25?cm, water tables of constant and periodically flooded, and N fertilizer rates of 0 and 168?kg ha?1?year?1. Periodic flooding increased plant uptake of manganese (Mn), silicon (Si), and boron (B). Yield increases associated with additional N indicate a potential need to develop fertilizer rate recommendations for shallow Histosols. Soil depth impacted sugarcane nutrient uptake with 25?cm of soil depth significantly affecting examined leaf nutrient concentrations except iron (Fe). Sugarcane yield may benefit if additional N and potassium (K) are added at rates specific to soil depth. Proximity to bedrock led to excessive calcium (Ca) uptake and low K and Fe DRIS (Diagnosis and Recommendation Integrated System) values were below recommendations. Data from this study can assist development of precision agricultural practices in the EAA that utilize soil depth.  相似文献   

14.
Abstract

Continued addition of irrigation water to the soil will add salts which may accumulate sufficiently to reduce plant growth and crop yields. Eventually, the accumulated salts may stop all growth, unless irrigation practices which move salts downward below the root zone are followed. Consequently, water is needed not only for growing plants but also for leaching salts out of the soil. The success of achieving these objectives primarily depends on the proper water management practices, which, in turn, depend on methods and timing of irrigation, quality and quantity of available water for irrigation, soil hydraulic properties, drainage systems, leaching requirement, and economics.  相似文献   

15.
ABSTRACT

The present studies were conducted to evaluate the effect of different nutrient management practices under two tillage options in wheat. The experiments were laid out in split-plot design with a combination of two varieties (WH 1105 and HD 2967) and two tillage options (Conventional and No tillage) in the main plot and six precision nutrient management practices [absolute control, site-specific nutrient management with Nutrient Expert for wheat (SSNM-NE)(170 kg nitrogen (N)/ha), SSNM NE+GreenSeeker (GS)(153/158 N kg/ha), N120 (120 kg N/ha) before irrigation, N120 after irrigation and N Rich (180 kg N/ha)] in subplot replicated thrice. The grain yield and quality characters in no tillage (NT) and conventional tillage (CT) were similar but agronomic efficiency was higher in NT. Both the varieties (WH 1105 and HD 2967) gave similar grain yield and quality. Wheat variety WH 1105 recorded significantly higher sodium dodecyl sulfate sedimentation (SDS) and gluten index. The treatment SSNM NE+GS had resulted in 107.1% higher grain yield than no nitrogen control but similar to enriched N plot (180 kg N/ha). The grain protein, SDS and gluten index in need-based nutrient management (SSNM+GS) treatment were found to be similar as recorded in SSNM-NE (170 kgN/ha) and N enriched plot (180 kg N ha?1). The agronomic efficiency and recovery efficiency in SSNM+GS were also better than SSNM NE.  相似文献   

16.
Abstract

Knowledge of crop response to temporary waterlogging is important in the development of effective water management practices. A field study was conducted to determine the response of soybean [Glvcine max. (L.) Merr] grown on a poorly drained, clayey soil to temporary flooding at three growth stages. The four treatments were soybean flooded for seven consecutive days at either VI, V4 or R2 growth stages at a flood height of 0.03 m above the soil surface and a well‐watered control. Flooding for seven consecutive days wetted but did not saturate the lower parts of the soil profile. This was attributed to the swelling by the montmorillonitic clay and subsequent sealing of the soil near the surface. In general, Eh and ODR decreased gradually during the flood, but increased as the soil dried upon removal of the flood. Canopy heights and dry weights of the flooded soybeans were dependent on plant growth stage at flooding and time of measurement but were lower than the control. When flooded at the VI or V4 growth stages, concentrations of N and K in the above‐ground plants were lower than the control after the flood. Three weeks after the flood was removed higher concentrations of these elements were found. When flooded at R2, concentrations of N and K were lower than in the control. Few differences were found in the plant concentrations of Ca, Mg, Mn, Fe, Al, and Na in the plant due to the flood, but by the end of the growing season, concentrations of Mn, Fe and Al were higher in the R2 flooded soybeans than in the other treatments. Seed yield response of the soybeans depended upon plant growth stage at flooding. The soybeans were particularly sensitive to the seven days of continuous flood at the R2 growth stage. Values of relative seed yield were 88, 83, and 44 % of the well watered‐control for the VI, V4 and R2 growth stages, respectively. Differences in seed yield were found with cultivar and with cultivar?flood treatment.  相似文献   

17.
Accumulation of excess sodium (Na+) in a soil causes numerous adverse phenomena, such as changes in exchangeable and soil solution ions and soil pH, destabilization of soil structure, deterioration of soil hydraulic properties, and increased susceptibility to crusting, runoff, erosion and aeration, and osmotic and specific ion effects on plants. In addition, serious imbalances in plant nutrition usually occur in sodic soils, which may range from deficiencies of several nutrients to high levels of Na+. The structural changes and nutrient constraints in such soils ultimately affect crop growth and yield. The principal factor that determines the extent of adverse effects of Na+ on soil properties is the accompanying electrolyte concentration in the soil solution, with low concentration promoting the deleterious effects of exchangeable Na+ even at exchangeable sodium percentage (ESP) levels less than 5. Consequent to an increase in the use of poor quality waters and soils for crop production, the problems of sodic soils can be expected to increase in future. The mechanisms that explain sodic behaviour can provide a framework in which slaking, swelling and dispersion of clay together with nutrient constraints in sodic soils may be assessed so that the practices to manage such soils can be refined for long‐term sustainable agriculture. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

18.
Dry bean (Phaseolus vulgaris L.) is an important food legume for the world population. However, its average yield is low worldwide. The main reasons for low yield are biotic and abiotic stresses. Maximum economic yield of a crop can be achieved with appropriate balance between plant and environmental factors during crop growth cycle. Adopting appropriate management practices in favor of high yields can modify some of these factors. Hence, knowledge of yield physiology of dry bean is important for understanding yield formation components during crop growth and development and consequently improving yield. Dry bean growth cycle is divided into vegetative and reproductive growth stages. During vegetative stage, development of roots, trifoliate, node, and branches take place. Main features of reproductive growth stage are flowering, pod and grain formation. Important plant traits associated with yield are root and shoot dry matter yield, pod number, 100 grain weight, leaf area index, grain harvest index, and nitrogen harvest index. These plant traits are genetically controlled and also influenced by soil and plant management practices. Higher yield is possible only when there is an adequate balance among various physiological processes or yield components. The objective of this review is to discuss growth and development of bean plant including yield formation process or traits during crop growth cycle and importance of these yield components in determining yield.  相似文献   

19.
ABSTRACT

We studied the effect of integrated nutrient management (INM) combinations on supplement of plant nutrient for quantitative and qualitative fruit production in sapota. Thus, 17 combinations of INM practices were evaluated on fruit yield of sapota and nutrient availability in a Vertisol of Chambal region, India. The results demonstrated that almost all treatment combinations comprised of recommended dose of fertilizer (RDF), i.e. 1,000:500:500 g NPK plant?1 with application of organic and inorganic sources of nutrients had a significant effect on the fruit yield of sapota, soil microbial biomass, NPK content of leaf, fruit and soil over control (T1). Among different treatments, application of 2/3rd part of RDF + 50 kg FYM + 250 g Azospirillum + 250 g Azotobacter plant?1 (T11) significantly enhanced the number of fruits plant?1 (327.88), yield plant?1 (29.03 kg) and yield ha?1 (4.52 t). However, the soil microbial count of fungi (8.89 cfu g?1 soil), bacteria (11.19 cfu g?1 soil) and actinomycetes (5.60 cfu g?1 soil) at fruit harvest was higher under the 2/3 of RDF +10 kg vermicompost + 250 g Azospirillum + 250 g Azotobacter plant?1 (T15). The leaf nitrogen content (N, 2.03%) was higher in T15, while phosphorus (P, 0.28%) and potassium (K, 1.80%) content were higher in T11. It is evident that treatment T11 increased fruit yield by 32% in Sapota cv. Kalipatti compared to control. Therefore, combined application of nutrient sources proved not only beneficial for enhancing fruit yield of sapota but also sustaining soil health in Chambal region of south-eastern Rajasthan.  相似文献   

20.
The growth of cucumber under open field conditions in the coast of Ecuador results in low yields being the growth under protected conditions a tentative solution, but there is little information about the nutritional status of this crop in this region. The objectives were to determine the yield, nutritional status as well as the water and nutrient use efficiencies. The different growing conditions were: multitunnel greenhouse with soilless system (GSL), multitunnel greenhouse with soil system (GS) and open field conditions with soil system (OFS). Cucumber plants grown under GSL had the highest yield. The nutrient concentration in leaf showed different trends: nitrogen (N), calcium (Ca) and iron (Fe) remained unchanged. Phosphorus (P), potassium (K), magnesium (Mg), copper (Cu), zinc (Zn) and manganese (Mn) showed variations according to the growing conditions and phenological stages. The highest values of water and nutrient use efficiencies under GSL were related to the highest yield.  相似文献   

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