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51.
Oil palm (Elaeis guineensis Jacq.) is a heavy feeder of nutrients and requires balanced and adequate supply of nutrients for optimum growth and yield. Information regarding soil nutrient status and leaf nutrient concentration is very much required for proper fertilizer application. Therefore, a survey was conducted for assessment of soil nutrient status and leaf nutrient concentration in 64 oil palm plantations in the state of Goa lying in the west coastal region of India. Soil pH, electrical conductivity (EC), organic carbon (OC), available potassium (K) (ammonium acetate-extractable K) (NH4OAc-K), available phosphorus (P) (Bray’s-P), exchangeable calcium (Ca) (Exch. Ca) and magnesium (Mg) (Exch. Mg), available sulphur (S) (calcium chloride-extractable S) (CaCl2-S), and hot water soluble boron (B) (HWB) in surface (0–20 cm depth) soil layers ranged from 4.25 to 6.77, 0.05 to 1.06 dS m–1, 5.07 to 48.4 g kg–1, 58.1 to 1167 mg kg–1, 1.80 to 415 mg kg–1, 200 to 2997 mg kg–1, 36.0 to 744 mg kg–1, 3.00 to 87.7 mg kg–1 and 0.09 to 2.10 mg kg–1, respectively. Diagnosis and Recommendation Integrated System (DRIS) norms were established for different nutrient expressions and were used to compute DRIS indices. As per DRIS indices, the order of requirement of nutrients in the region was found to be P > Mg > K > nitrogen (N) > B. Optimum leaf nutrient ranges as per DRIS norms varied from 1.64 to 2.79%, 0.36 to 0.52%, 0.37 to 0.75%, 0.89 to 1.97%, 0.35 to 0.63%, 0.89 to 1.50%, 3.10 to 13.9 mg kg?1, 7.50 to 32.2 mg kg?1, 35.0 to 91.1 mg kg?1, 206 to 948 mg kg?1, and 895 to 2075 mg kg?1 for N, P, K, Ca, Mg, S, B, copper (Cu), zinc (Zn), manganese (Mn), and iron (Fe) respectively. On the basis of DRIS-derived sufficiency ranges, 14, 5, 11, 6, 6, 6, 8, 2, 3, 6, and 16% of leaf samples had less than optimum concentrations of N, P, K, Ca, Mg, S, B, Cu, Zn, Mn, and Fe respectively. The optimum ranges developed can be used as a guide for routine diagnostic and advisory purpose for balanced utilization of fertilizers.  相似文献   
52.
香蕉营养诊断的DRIS标准的初步研究   总被引:4,自引:0,他引:4  
运用诊断与推荐综合系统(DRIS)标准建立的常规方法,通过比较香蕉低产组和高产组叶片N、P、K、Ca、Mg和S养分含量以及两元素间的养分比和养分积,初步筛选出P/N、N.K、N.Ca、N/Mg、N/S、P.K、P/Ca、P/Mg、P.S、Ca/K、K/Mg、K.S、Ca/Mg、Ca/S和S/Mg作为DRIS参项,并初步提出香蕉DRIS诊断标准。  相似文献   
53.
假定植株叶片养分含量比值与其对应的标准值的欧氏距离与植株生物量或产量之间存在线性关系,由此数学模型可估计植株叶片养分含量比值的标准值。根据模型估计的标准值建立了诊断植株养分平衡状况的方法(称为改进的DRIS法),由此方法诊断结果与DRIS诊断结果基本吻合。  相似文献   
54.
毛竹营养诊断的研究   总被引:17,自引:3,他引:17       下载免费PDF全文
本文探讨毛竹的叶营养诊断,以指导竹林施肥。研究内容包括叶分析的正确采样方法,用传统的临界值法和近期发展起来的新方法——DRIS诊断毛竹肥料试验的营养状态。结果表明: 1.毛竹的孕笋中期是采样的最佳时期;二年生立竹中部枝叶是取样的理想部位;一个叶平均样品至少采自5个单株才能达到分析精度的要求。 2.不同立竹结构对临界浓度标准有影响,每亩立竹250株以上的竹林,N、P浓度临界值分别为2.6%和0.13%,理想值为2.8%和0.16%。密度稀疏或钩梢竹林,N浓度临界值和理想值为2.9%和3.1%。新竹产量与N、P浓度反应相一致。 3.DRIS诊断参数从三年新竹产量大于3500kg/亩的高产群计算出来。DRIS诊断使用N、P、K、Si四组叶分析资料,诊断结果与临界值法基本一致。DRIS法的好处在于可以对营养平衡状况和需求顺序作出判断。但是养分相对不足或过量也可能误诊。考虑到森林立地条件的不均一性,应该推荐两种方法同时并用。  相似文献   
55.
湿地松幼林营养的DRIS诊断*   总被引:7,自引:1,他引:7       下载免费PDF全文
用DRIS和临界浓度值法对湿地松幼林的营养状态比较研究发现,在诊断针叶磷素营养状态时,用DRIS法比临界浓度值法更准确。施用磷肥能显著地提高湿地松幼林生长量,并与DRIS措数密切相关;但与叶片中磷的浓度相关不显著。植株从磷肥吸收的磷量被林分生长的“稀释效应”所抵消,使施磷植株叶片中磷的浓度没有明显提高。同临界浓度值法一样,DRIS法也受林龄和立地环境因素的影响,故用于计算诊断参数的高产群体应当从当地的同龄林选择。根据DRIS的诊断结果,江西永丰低丘红壤湿地松造林施肥的效应机理为:氮肥增加针叶N素的过量积累,加剧了养分的不平衡状态,对生长无益。单施钙镁磷肥,每公顷施纯磷21.82kg,就可全面改善幼林的营养状态,使主要养分元素N、P、Ca、Mg达到理想的平衡状态,显著促进幼林生长。钾肥提高幼林钾的吸收量,但可能属奢侈吸收状态,对生长无影响。  相似文献   
56.
ABSTRACT

Diagnosis and recommendation integrated system (DRIS) norms were computed from the data on leaf mineral composition, soil available nutrients, and corresponding mean fruit yield of three years (1999–2002), collected from the set of 57 irrigated commercial ‘Nagpur’ mandarin (budded on Citrus jambhiri Lush) orchards, representing 26 locations and 3 basalt derived soil orders (Entisols, Inceptisols, and Vertisols) rich in smectite minerals. The DRIS norms derived primarily from spring-cycle index leaves from non-fruiting terminals sampled during August to October (6–8 months old) suggested optimum leaf macronutrient concentration (%) as: 1.70–2.81 nitrogen (N), 0.09–0.15 phosphorus (P), 1.02–2.59 potassium (K), 1.80–3.28 calcium (Ca), and 0.43–0.92 magnesium (Mg). While, optimum level of micronutrients (ppm) was determined as: 74.9–113.4 iron (Fe), 54.8–84.6 manganese (Mn), 9.8–17.6 copper (Cu), and 13.6–29.6 zinc (Zn) in relation to fruit yield of 47.7–117.2 kg tree? 1. Likewise, DRIS indices for soil fertility developed from dripline soil samples collected at 0–20 cm depth corresponding to similar level of fruit yield, the optimum limit of soil available nutrients (mg kg? 1) was observed as: 94.8–154.8 N, 6.6–15.9 P, 146.6–311.9 K, 401.0–601.6 Ca, 85.2–369.6 Mg, 10.9–25.2 Fe, 7.5–23.2 Mn, 2.5–5.1 Cu, and 0.59–1.26 Zn. Primary DRIS indices developed on the basis of leaf and soil analysis revealed deficiency of N, P, K, Fe, and Zn. The nutrient constraints so diagnosed were further verified through fertilizer response studies carried out on a representative Typic Haplustert soil type facing multiple nutrient deficiencies, and accordingly suggested the revised fertilizer schedule.  相似文献   
57.
温州蜜柑矿质营养综合诊断研究   总被引:4,自引:0,他引:4  
运用诊断施肥综合法(DRIS)研究了四川简阳县成年温州蜜柑3要素的营养状况。结果表明:DRIS法与传统的适宜诊断法相比,不仅可诊断营养元素的高低水平。还具有衡量养分平衡的能力。试验发现,尽管两低产果园的氮、磷、钾含量都在适宜范围之下,但其限制产量的养分顺序分别是P、K、N和K、P、N。这为配方施肥、平衡施肥提供了理论依据。  相似文献   
58.
Abstract

The objective of this work was to calibrate, classify, and establish soil and plant reference norms for evaluating the nutritional status of the Horn plantain crop (Musa AAB, subgroup plantain cv. Horn). The sampling unit consisted of the “mother” plant and its corresponding soil at the fertilization band. Soil samples at depths of 0–20 cm and 21–40 cm were analyzed. A total of 221 sampling units were studied, hence, 442 soil and 221 leaf samples were used to develop the reference norms. A regression model with linear combinations of the soil and leaf variables for yield estimation was established by using the stepwise method. The model showed a high significant adjustment of 52% (R2) with normality of the standard residues. Four yield subclasses in kg cluster?1 as 10.9–13.9 (60 units), 14.0–17.9 (92 units), 18.0–19.9 (47 units), and 20 or more (17 units) were defined. With the means of the soil and leaf data linearly related with yield, the reference norms for each subclass were developed. The method thereby established permits to develop reference norms that can be used for the simultaneous interpretation of soil and leaf analysis data and for yield estimation of the Horn plantain crop.  相似文献   
59.
Abstract

The Diagnostic and Recommendation Integrated System (DRIS) was employed for interpreting nutrient analyses of leaf tissue of guava fruit trees (Psidium guajava L.) cultivated in Punjab, northwest India. Standard reference DRIS norms were established for various nutrient ratios and used to compute DRIS indices, which assessed nutrient balance and order of limitation to yield. The DRIS evaluation and sufficiency range approach were equally effective and in agreement for diagnosing deficiencies of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), sulfur (S), manganese (Mn), zinc (Zn), and copper (Cu). The results also show that the position of leaf tissue sampled does not have a major effect on the DRIS diagnosis. Nutrient sufficiency ranges derived from DRIS norms were 1.41–1.65, 0.10–0.17, 0.51–0.97, 1.16–2.12, 0.31–0.51, 0.18–0.28% for N, P, K, Ca, magnesium (Mg), and S and were 105–153, 58–110, 15–29, and 6–16 mg Kg?1 for iron (Fe), Mn, Zn, and Cu, respectively. According to these sufficiency ranges 35, 62, 51, 75, 70, and 68% of samples were sufficient, and 4, 29, 36, 9, 10, and 22% of samples were low in N, P, K, Ca, Mg, and S, respectively. More than 50 and 2% of the guava trees selected for sampling was found to deficient in N and P, respectively. For micronutrients, 15, 6, and 7% of samples were found to be low in Mn, Zn, and Cu.  相似文献   
60.
Considerable amounts of phosphorus (P) fertilizer will be required on soils in the proposed Ord Stage II area of northwestern Australia if a sustainable dry‐season cotton production system is to be established, because in their virgin state the soils are known to be inherently low in P. This study aimed to determine P fertilizer requirements on these soils to optimize cotton yield as well as nutrient uptake. Five rates of P fertilizer were applied to soil recently cleared of trees and prepared for irrigation. In the second year, these same rates were imposed over the trial. We conclude that the application of 60 kg ha?1 of P was sufficient to allow maximum yield and quality for dry‐season cotton grown in the first season on virgin soils in the Ord River Irrigation Area, whereas a total of 80 kg ha?1 of P was required when cotton was grown over two seasons.  相似文献   
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