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101.
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   
102.
The uptake of micronutrient cations in relation to varying activities of Mn2+ was studied for barley (Hordeum vulgare L. var. Thule) and oat (Avena sativa L. var. Biri) grown in chelator buffered nutrient solution. Free activities of Mn2+ were calculated by using the chemical speciation programme GEOCHEM-PC. Manganese deficient conditions induced elevated concentrations of Zn and Fe in shoots of both species. The corresponding antagonistic relationship between Mn and Cu could only be seen in barley. The observed antagonistic relationships were only valid as long as the plant growth was limited by Mn deficiency. The Mn concentration in both plant species increased significantly with increasing Mn2+ activity in the nutrient solution. The concentration of Mn in the shoots of oat was higher than for barley except under severe Mn deficiency where it was found equal for both species. Manganese was accumulated in the roots of barley at high Mn2+ activity. The different shoot concentrations of Mn between barley and oat are therefore attributed to the extent of Mn translocation from roots to shoots. Manganese deficiency induced a significant increase in the shoot to root ratio in both species.  相似文献   
103.
Barley (Hordeum vulgare L.) plants were grown hydroponically in a greenhouse for 14 d under Fe-deficient conditions before treatment for 3 h with excess Mn (25 µM) and equimolar amounts of plant-borne (phytosiderophores, PS) or synthetic (ethylene diamine tetraacetic acid, EDTA) metal chelators. The xylem sap was collected for 3 h and analyzed for PS, Fe, Mn, Zn, Cu, and citrate concentrations. Excess Mn in the feeding medium decreased the concentrations of PS, Fe, Zn, and Cu in the xylem sap. Addition of 25 µM Mn and an equimolar amount of PS to the feeding medium increased the concentrations of PS, Fe, and Cu in the xylem sap, while EDTA decreased the concentrations of PS and the above nutrients. Excess Mn in the feeding medium increased the Mn concentration in the xylem sap and this increase was more pronounced with the addition of PS to the feeding medium, while EDTA had a depressing effect. These findings suggested that the roots of Fe-deficient barley plants can enhance the absorption and/or translocation of both Mn2+ and a PS-Mn complex. Addition of excess Mn to the feeding medium, irrespective of chelators, did not affect the xylem citrate concentration, indicating that citrate may not contribute to the translocation of metal micronutrients. In the xylem sap of Fe-deficient barley plants, the concentrations of metal micronutrients were positively correlated with the concentrations of PSG  相似文献   
104.
Greenhouse experiments were conducted to assess the effects of salinization of soil on emergence, growth, water status, proline content, and mineral accumulation of seedlings of Acacia auriculiformis A. Cunn. ex Benth. (Fabaceae). Sodium chloride (NaCl) was added to the soil and salinity was maintained at 0.3, 3.9, 6.0, 7.9, 10.0, 12.1, and 13.9 dS m?1. Salinity caused reduction in water potential of tissues, which resulted in internal water deficit to plants. Consequently, seedling growth significantly decreased with increase in soil salinity. Proline content in tissues increased with increase in salinity. Potassium and sodium content significantly increased in tissues as salinity increased. Nitrogen content significantly increased in tissues with salinization of soil. Phosphorus, calcium and magnesium content significantly decreased as salinity increased. Changes in tissues and whole-plant accumulation patterns of other nutrients, as well as possible mechanisms for avoidance of sodium toxicity in this tree species in response to salinity, are discussed.  相似文献   
105.
A greenhouse experiment was conducted to evaluate the effect of six rates of filter cake and bagasse ash each separately (0, 20, 40, 60, 80, and 100 ton ha?1) on nutrients uptake and utilization efficiency of wheat in nitisol. Filter cake application was found to better increase in nitrogen (N), sodium (Na), calcium (Ca), potassium (K), and magnesium (Mg) uptake and utilization efficiency while bagasse ash influenced zinc (Zn) and copper (Cu) uptake. Bagasse ash application also reduced the uptake of iron (Fe) and manganese (Mn) by wheat. Multiple regression analysis showed that the soil properties explained selected macronutrients and micronutrients uptake. Exchangeable acidity negatively explained some of the nutrient uptakes. In general, filter cake and bagasse ash were found effective in enhancing the nutrient uptake and utilization efficiency by wheat cultivated in acidic soils such as nitisol.  相似文献   
106.
The mineral concentration of flowers and the seasonal fluctuation of macro- [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg)] and micronutrients [iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu)] in leaves of male, female, and hermaphroditic carob trees (Ceratonia siliqua L.) were studied. The nutrient dynamics were linked not only to phenological events, but also to the gender of the trees. The females were able to allocate more nutrients to leaves than male trees, even though male flowers were richer in particular elements such as N and Zn. The hermaphrodites supported the development of both inflorescences and fruits with a lower seasonal variation and a lower leaf nutrient concentration, as compared to the other genders, which may indicate a more efficient use of resources. Flowers had, in general, a higher concentration of N, P, and K, and a lower Mn concentration than in leaves. Flowers of the females had a lower nutrient concentration compared to males or hermaphrodites.  相似文献   
107.
Secondary and trace elements may be limiting soil microbial functioning, albeit microbial demand and content remain largely unknown and methods for their in situ detection are limited. Thus, the objective of the present study was to take the first step towards the method development for the assessment of the soil microbial ionome, that is, the elemental composition of soil microbial communities. Chloroform (CHCl3) fumigation extraction was used for the detection of microbial CHCl3-labile secondary and trace element concentrations in soils. The suitability of two extractants (NH4NO3, CaCl2) for the quantification of CHCl3-labile concentrations of phosphorus, sulphur, potassium, sodium, and magnesium, as well as selenium, iron, zinc, manganese, copper, cobalt, nickel, molybdenum, vanadium, boron, silicon, barium, arsenic, and cadmium, were tested in six agricultural soils. Additionally, three soil to extractant ratios (1:5, 1:10, and 1:20) and two extraction durations, 1 or 2 h, were tested in a subset of two soils. Out of the two extractants tested, 0.01 M CaCl2 was found to be the best-suited extractant. For CaCl2, a soil-to-extractant ratio of 1:20 with an extraction time of 1 h was best for the majority of elements in the two soils tested. In a limited number of agricultural soils, we were able to show that CHCl3 fumigation extraction can successfully be applied to the elements phosphorus, sulphur, potassium, sodium, magnesium, zinc, manganese, copper, nickel, vanadium, boron, silicon, and barium to yield a CHCl3-labile element fraction. Conversion values to microbial biomass, accounting for elements contained in the cell envelope components, which are mostly not extractable, and to account for adsorption to soil colloids during extraction are yet to be determined in a larger variety of soils. To overcome some of the limitations of the fumigation extraction approach for secondary and trace elements, a pre-extraction step may provide a suitable solution.  相似文献   
108.
Adequate soil conditions and fertilization as a cultural practice are the basis of fruit crops production. This study was conducted in 2011 and 2012 to determine impact of soil application of complex nitrogen, phosphorus, and potassium (NPK) mineral fertilizer alone and its mixture with cattle manure (M) and natural zeolite (A) on yield, fruit physico-chemical traits and leaf micronutrient amounts at 120 days after full bloom (DAFB) in “Idared” and “Melrose apples grown on heavy and acidic soil under Serbian conditions. Results showed that NPK increased yield in “Idared” and both NPK+A and NPK+M in “Melrose.” Fertilizer applications were not influenced by fruit physico-chemical attributes, but differences between cultivars were significant. Fertilizers induced changes of leaf micronutrients amount, but effect was not consistent. In “Idared,” NPK+A and NPK+M mixtures improved amounts of the most micronutrients, whereas in “Melrose,” NPK and mixture NPK+A+M increased leaf micronutrients in more cases. According to deviation from optimum percentage (DOP and ΣDOP indexes), excessive leaf iron (Fe) and zinc (Zn) was found and deficiency of manganese (Mn), copper (Cu), and boron (B). “Melrose” exhibited much better balanced nutritional values for nutrients as compared to “Idared,” whereas NPK+M in “Idared” and NPK alone in “Melrose” promoted better balanced nutritional values. Since the impact of nutrients on the studied features is not consistent, more research will need to be conducted to investigate the long-term effect of NPK alone or in mixture with natural zeolite and manure fertilization on apples.  相似文献   
109.
Interaction among plant nutrients can yield antagonistic or synergistic outcomes that influence nutrient use efficiency. To provide insight on this phenomenon, peer-reviewed articles were selected that quantified the interaction effects of nutrients on crop yield levels. In total 94 articles were selected that described 117 interactions between all macro- and micronutrients for different agricultural crops. In 43 cases the interaction was synergistic, in 17 cases the interaction was antagonistic, and in 35 cases the interaction was zero-interaction; the other 23 cases were non-significant (16) or showed a negative response (7). Generally: (a) when the availability of two nutrients is characterized as deficient, a large increase in yield can be expected by diminishing these deficiencies: (b) for most macronutrients the mutual interactions on yield levels are synergistic; and (c) antagonistic effects on yield are often found for divalent cations. Knowledge of nutrient interactions can guide fertilizer design and optimization of fertilization strategies for high yields and high nutrient use efficiencies.  相似文献   
110.
‘Bouquet Purple’ pinks (Dianthus sp.) were grown in silica-sand culture to induce and photograph symptoms of nutritional disorders. Plants received a complete modified Hoagland's all-nitrate (NO3) solution. Nutrient-deficient treatments were induced with a complete nutrient formula minus one of the nutrients, and a boron (B)-toxicity treatment was induced by increasing B 10-fold in the complete nutrient formula. Plants were monitored daily to document sequential series of symptoms as they developed. Typical symptomology of nutrient disorders and corresponding tissue concentrations were determined. All treatments exhibited deficiency symptomology. Disorders for nitrogen (N), iron (Fe), calcium (Ca), and sulfur (S) were the first to manifest in pinks. Unique symptomology was observed for plants grown under potassium- (K), B-, copper- (Cu), and molybdenum- (Mo) deficient conditions, which supported the need for a species-specific approach when characterizing nutrient disorders of floriculture crops.  相似文献   
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