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1.
Various approaches for the Diagnosis and Recommendation Integrated System (DRIS) indices were employed like Beaufil's ER, Elwali and Gascho and Jones. As per the Beaufil's approach of DRIS indices, the nutrient requirements in the initial stage of the apple tree were magnesium > nitrogen > sulfur > phosphorus > copper > zinc > iron > manganese > boron > calcium > potassium (Mg > N > S > P > Cu > Zn > Fe > Mn > B > Ca > K) and in the later stage at 40–50 years, the nutrient requirements were S > Cu > Mg > Fe > P > N > Ca > Mn > K > Zn > B, thus demanding a foliar application of magnesium salt and urea which are required in high amounts in the initial stage; however in the later stage, the yield depression was not attributed to the nutrient deficiency but rather trees' genetic make-up which destabilizes the higher yield in the period of 50 years. Nutrient sufficiency ranges for apple derived from DRIS norms were 1.91–2.24, 0.18–0.26, 1.11–1.61, 1.74–1.88, 0.30–0.33 and 0.28–0.30% for nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S), respectively.  相似文献   

2.
Spatial variability of soil properties and accompanying variability in plant nutrient concentrations in a banana growing enterprise were mapped using Geographic Information Service (GIS) technique to test the diagnostic sensitivity of Diagnosis and Recommendation Integrated System (DRIS) system. Variogram models of soil properties indicated that most of the properties exhibited definable spatial structures. The pH, available nitrogen (N), calcium (Ca), magnesium (Mg), iron (Fe), manganese (Mn) and zinc (Zn) showed strong spatial dependence, whereas available phosphorus (P), potassium (K), and sulfur (S) showed moderate dependence. Most of the plant nutrients exhibited higher nugget/sill ratio indicating often mismatch between soil available nutrient and plant nutrient concentrations. DRIS indices showed high diagnostic sensitivity for N, P, K, Ca, and Fe. Application of GIS for nutrient mapping along with DRIS was found useful for identification of yield limiting nutrients in soil and plant for developing nutrient management strategies.  相似文献   

3.
Abstract

Diagnosis and Recommendation Integrated System (DRIS) indices were developed to identify and prioritize the yield‐limiting nutrients in mango orchards (cv. Baneshan) in Andhra Pradesh, India. The forms of expressions selected for computing the DRIS indices varied from the young (<20 years old) to aged (>20 years old) trees. The DRIS indices could reflect the long‐term variations of different doses of nitrogen (N), phosphorus (P), and potassium (K) application in mango, thereby showing the sensitivity of the newly developed DRIS indices to fertilization practices. The nutrients identified as yield limiting by DRIS indices were observed to be not totally independent of the age of sampled tissue. The same nutrient was observed to be most yield limiting in 24.2% of sampled trees after a gap of 3 months. Similarly, the same nutrient was identified as one of the first two yield‐limiting nutrients in 52.2% of sampled trees. The validity of the newly developed DRIS indices was tested by applying two of the most yield‐limiting nutrients in 88 and 46 cases of young and aged trees. The yield‐limitation due to individual nutrients was either totally eliminated or changed in ranking in 96.0 and 93.5% of the young and aged trees, respectively, after the application of yield‐limiting nutrients, as indicated by the newly developed DRIS indices. The increase in the fruit yield with the application of yield‐limiting nutrients identified by the DRIS indices varied from 11.5 to 45.9% in young trees and from 15.2 to 34.0% in aged trees over the control.  相似文献   

4.
A survey was conducted for assessment of soil fertility status, leaf nutrient concentration and finding yield-limiting nutrients of oil palm (Elaeis guineensis Jacq.) plantations in Mizoram state situated in the northeastern part of India. Soil pH, electrical conductivity (EC), organic carbon (OC), available potassium (K), available phosphorus (P) (Bray's-P), exchangeable calcium (Ca) (Exch. Ca) and magnesium (Mg) (Exch. Mg), available sulfur (S) (CaCl2-S), and hot-water-soluble boron (B) (HWB) content in surface (0–20 cm depth) and subsurface (20–40 cm depth) soil layers varied widely. Diagnosis and Recommendation Integrated System (DRIS) norms were established for different nutrient expressions, and DRIS indices were computed. As per DRIS indices, the order of requirement of nutrients was found to be B > K > Mg > P > nitrogen (N). Optimum leaf nutrient ranges as per DRIS norms varied from 1.91% to 2.95%, 0.46% to 0.65%, 0.63% to 1.00%, 0.48% to 0.88%, and 9.41 to 31.0 mg kg?1 for N, P, K, Mg, and B, respectively. On the basis of DRIS-derived optimum ranges, 32%, 9%, 27%, 12%, and 12% leaf samples had less than optimum concentration of N, P, K, Mg, and B, respectively. The optimum ranges developed could be used as a guide for routine diagnostic and advisory purpose for efficient fertilizer application.  相似文献   

5.
广西壮族自治区与福建省荔枝园土壤养分肥力现状研究   总被引:4,自引:1,他引:3  
掌握土壤养分肥力,是制定施肥策略的基础。本研究采集了广西壮族自治区荔枝主产区果园土壤样本185个,福建省荔枝主产区果园土壤样本25个,分析了土壤有机质和N、P、K、Ca、Mg、S、Cu、Zn、B、Mo含量,评价荔枝果园土壤养分肥力现状。结果显示:广西和福建两省荔枝果园土壤有机质、碱解氮、速效钾、有效钙、有效镁、有效硼、有效钼含量均为低水平,广西荔枝果园有效磷和有效锌为中下,福建为中上,有效铜中等,有效硫含量较高。整体上两省荔枝园土壤养分肥力较低且不平衡。不同荔枝主产区土壤养分肥力状况差别很大,硼是广西荔枝园土壤最普遍缺乏的元素,镁、钼次之。而镁是福建荔枝园土壤最普遍缺乏的元素,硼、钙次之。  相似文献   

6.
The diagnosis and recommendation integrated system (DRIS) approach was used to interpret nutrient analyses of leaf tissues from pomegranate cv. Bhagwa orchards grown in southwestern Maharashtra, India. The DRIS norms were established for three growth stages,viz. 50% flowering, fruit development and first harvesting of pomegranate. Various nutrient ratios were obtained from high-yielding population and were used to compute DRIS indices for diagnosing nutrient imbalances and their order of limitation to yield. Nutrient sufficiency ranges at 50% flowering derived from DRIS norms were 1.32–2.15% nitrogen (N), 0.18–0.24% phosphorus (P), 1.29–1.99% potassium (K), 0.64–1.20% calcium (Ca), 0.23–0.45% magnesium (Mg), 0.16–0.26% sulfur (S), 103.04–149.12 mg kg?1 iron (Fe), 39.60–72.85 mg kg?1 manganese (Mn), 15.99–26.10 mg kg?1 zinc (Zn), 6.16–9.32 mg kg?1 copper (Cu), 23.38–39.88 mg kg?1 boron (B) and 0.29–0.47 mg kg?1 molybdenum (Mo). Similarly, the sufficiency range at fruit development and first harvesting was developed for computing DRIS indices. The requirement of Fe, Mg, S, Zn and N by the pomegranate plant was higher at 50% flowering and fruit development stages. According to these DRIS-derived indices, 87.85, 73.83, 70.09, 69.16 and 65.42% orchards were deficient in Fe, S, Mg, Zn, and N, respectively, at 50% flowering, while 70.03, 66.36, 63.55, 61.68, and 68.22% orchards were found to be deficient in respective nutrients during the fruit development stage.  相似文献   

7.
The objective of this work was to propose preliminary Diagnosis and Recommendation Integrated System (DRIS) norms and derive critical levels and nutrient sufficiency ranges in the leaves of guava plants in commercial nursery conditions. Sixty-eight leaf samples were evaluated from fertilization trials with seedlings. In the low-yield subpopulation (84% of the population), the limiting nutrients by deficiency in descending order were nitrogen (N)> copper (Cu)>phosphorus (P) = potassium (K)> manganese (Mn)> iron (Fe) = zinc (Zn)> sulfur (S)> boron (B) = magnesium (Mg)> calcium (Ca), and the limiting ones by excess in descending order were B > Ca > Fe > Mn > S > Mg > Cu > P > Zn > N = K. The ranges of the appropriate DRIS indices were 24 to 28, 2.4 to 3.1, 21 to 29, 6 to 8, 1.9 to 2.9 and 1.9 to 2.3 (g kg?1) for the macronutrients N, P, K, Ca, Mg and S, respectively, and 35 to 48, 4 to 15, 68 to 93, 31 to 60 and 180 to 245 (mg kg?1) for the micronutrients B, Cu, Fe, Mn and Zn, respectively. The dry matter production of guava seedlings was associated with the nutritional status.  相似文献   

8.
Abstract

The Diagnosis and Recommendation Integrated System (DRIS) was used to identify nutrient status of mango fruit trees in Punjab, India. Standard norms established from the nutrient survey of mango fruit trees were 1.144, 0.126, 0.327, 2.587, 0.263, 0.141% for nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S), and 15, 3.5, 145, 155, and 30 mg kg?1, respectively, for zinc (Zn), copper (Cu), iron (Fe), manganese (Mn), and boron (B) in dry matter. On the basis of DRIS indices, 16, 15, 12, 17, and 16% of total samples collected during nutrients survey of mango trees were low in N, P, K, Ca, and Mg, respectively. For micronutrients, 19, 18, 12, 20, and 6% samples were inadequate in Zn, Cu, Fe, Mn, and B, respectively. DRIS‐derived sufficiency ranges from nutrient indexing survey were 0.92–1.37, 0.08–0.16, 0.21–0.44, 1.71–3.47, 0.15–0.37, and 0.09–0.19% for N, P, K, Ca, Mg, and S and 11–19, 1–6, 63–227, 87–223, and 16–44 mg kg?1 for Zn, Cu, Fe, Mn, and B, respectively.  相似文献   

9.
This work was performed in the Rio de Janeiro State, Brazil, with the objective to evaluate the nutritional status of yellow passion fruit plants along different phenological stages, using the DRIS method. Fifty-four passion fruit cultivated areas with an annual yield productivity ranging from 6.95 to 33.8 t ha?1 year?1 and average productivity of 16.9 t ha?1 year?1 were selected in the region. The contents of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), chlorine (Cl), iron (Fe), zinc (Zn), manganese (Mn), and boron (B) were evaluated. The reference standards were established (mean and variation coefficient) for the values of the nutrient concentration ratios, two by two, on samples from high yield productivity plantations and analyzed by the DRIS index of nutrients for the medium and low yield productivity areas. The established standards differed according with the phenological stage of the culture. In a general way, the mean content of the evaluated nutrients did not differed between the two productivity levels into each phonological stage. There was a difference for the Nutritional Limitation Order between different phenological stages of yellow passion fruit plants. The most negative DRIS indexes and the highest absolute values for the Average Nutritional Balance on yellow passion fruit plants in the region, were found for potassium in May, phosphorus in October and iron in January.  相似文献   

10.
This study aimed to evaluate six Diagnosis and Recommendation Integrated System (DRIS) calculation methods, including two ways to choose the nutrient ratio [F (Letzsch) or R (Nick) values] combined with three functions (Beaufils, Jones, or Elwali and Gascho), and to generate nutritional diagnoses for oil palm. A total of 144 foliar samples in 33 plots in the Eastern Amazon, Brazil, were used. Except for potassium (K) in all calculation methods, the DRIS indices showed no correlation with soil nutrients. Regardless of the formula, the nutritional balance index correlated with the productivity (significant r values) and similar diagnostics were obtained. These diagnoses were reliable according to the chi-square test (χ2), and most observed frequencies presented χ2 calculated less than χ2 tabulated. The average frequencies of samples with nutrient deficiency were 51%, 42%, 37%, 35%, 32%, 30%, 30%, 25%, 20%, 12%, and 12% for samples with nitrogen (N), boron (B), manganese (Mn), sulfur (S), K, copper (Cu), iron (Fe), zinc (Zn), calcium (Ca), phosphorus (P), and magnesium (Mg), respectively. All tested DRIS methods may be used, and their diagnoses indicate the most common nutritional deficiencies in oil palm.  相似文献   

11.
Abstract

A regional survey was conducted in commercial orchards of pomegranate (Punica granatum L.) in order to develop diagnostic norms and for evaluation of yield limiting nutrients in low yielding orchards. The leaf nutrient status was interpreted using Diagnosis and Recommendation Integrated System (DRIS) and Compositional Nutrient Diagnosis (CND). The correlation structure among the nutrients was extracted by Principal Component Analysis (PCA). The departure of DRIS indices from their CND counterparts was relatively small and a highly significant positive correlation was obtained between DRIS and CND indices. The three principal components explained 59.5% of the variation in the high yielding population and the designated PCS were (N+S+Zn+Fe‐Mn‐), (N+P+Ca+Zn‐), and (K‐S+). Pomegranate is mainly grown on marginal soils with low fertility and hence more than two or three nutrients were found to be limiting yields. However, nitrogen (N) and zinc (Zn) were the most common yield limiting nutrients. The DRIS and CND indices for low‐yielding orchards are reported and discussed.  相似文献   

12.
This article addresses the establishment of integrated diagnostics and recommendation system (DRIS) standards for irrigated bean crops (Phaseolus vulgaris) and compares leaf concentrations and productivity in low- and high-productivity populations. The work was carried out in Santa Fé de Goiás, Goiás State, Brazil, in the agricultural years 1999/2000 and 2000/2001. For the nutritional diagnosis, leaf samples were collected, and leaf concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), boron (B), copper (Cu), iron (Fe), manganese (Mn), and zinc (Zn) were established in 100 commercial bean crops. A database was set up listing the leaf nutrient content and the respective productivities, subdivided into two subpopulations, high and low productivity, using a bean yield value of 3000 kg ha?1 to separate these subpopulations. Sufficiency values found in the high-productivity population matched only for the micronutrients B and Zn. The nutritional balance among the populations studied was coherent and was lower in the high-productivity population. The DRIS standards proposed for irrigated bean farming were efficient in evaluating the nutritional status of the crop areas studied. Calcium, Cu, and S were found to be the least available nutrients, indicating high response potential for the fertilizing using these nutrients.  相似文献   

13.
黄兰  周卫军  崔浩杰  周奕廷  曹胜  刘双 《土壤》2020,52(2):287-293
为了弄清湖南省柑橘园土壤中、微量养分的丰缺及其分布特征,并合理调控柑橘园土壤中、微量养分,采集了湖南省柑橘园主产区14个县共84个土壤样品,检测了土壤中、微量元素的含量状况。结果表明:湖南省柑橘园土壤有86.8%样点呈酸性或强酸性;56.1%样点有机质含量偏低;交换性钙、交换性镁含量较适宜柑橘生长,但分布不均衡,其中湘南56%的样点钙含量不足,湘西南53.6%样点钙含量不足和64.3%样点镁含量不足;有效硫、铁、锰含量均偏高,偏高的比例分别为80.8%、86.9%,64.3%;有效铜含量丰富,但分布不均衡,其中湘南和湘西南分别有76.9%和78.6%样点含量偏高;76.2%样点有效锌含量适宜;85.5%样点有效硼处于缺乏状态;有效钼仅湘南有53.9%地区含量丰富,湘西北、湘西南地区含量适宜。相关性分析表明,柑橘园土壤pH与交换性钙、交换性镁及有效硫,有机质与有效硼、有效锌,以及其余养分间存在一定的相关性。因此,湖南省柑橘园土壤中、微量养分分布不均衡,3个主产区均存在制约柑橘生长发育的问题,据此建议调剂土壤pH,加大有机肥的施用,同时根际施用与叶面喷施相结合,适当补充硼、锌肥。  相似文献   

14.
The Diagnostic Recommendation and Integrated System (DRIS) was employed to interpret nutrient analyses of leaf tissues from ber fruit tree orchards grown in semi-arid and arid areas of Punjab in northwest India. The DRIS norms were established for various nutrient ratios obtained from the high-yield population and were used to compute DRIS indices, which assessed nutrient balance and their orders of limitation to yield. Nutrient sufficiency ranges derived from DRIS norms were 0.688–1.648%, 0.184–0.339%, 1.178–1.855%, 1.064–1.768%, 0.234–0.391%, and 0.124–0.180% for nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S) and were 55–205, 26–80, 17–33, and 5–11 mg kg?1 for iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu), respectively. According to these DRIS-derived sufficiency ranges, 79%, 76%, 76%, 75%, 84%, and 72% of samples were sufficient, whereas 13%, 15%, 21%, 14%, 7%, and 18% of total samples were low in N, P, K, Ca, Mg, and S, respectively. For micronutrients, 84%, 85%, 77%, and 86% of samples were sufficient, whereas 6%, 3%, 8%, and 2% of samples were low in Fe, Mn, Zn, and Cu, respectively.  相似文献   

15.
Abstract

Among several methods of diagnosis for nutritional status, two are more important: the Sufficiency range approach (SRA) and the diagnosis and recommendation integrated system (DRIS). This research compared DRIS with SRA, the diagnostic method currently used by the citrus industry in São Paulo State, Brazil. The study was conducted in irrigated, commercial groves of “Valencia” sweet orange more than six years old and with yield above 40 t ha? 1 in Mogi Guaçú, São Paulo State. Data pertaining to yield, tree spacing, rootstock, and foliar concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), iron (Fe), manganese (Mn), copper (Cu), zinc (Zn), and boron (B) in non-fruiting terminals for each plot were processed for the years 1994 through 1998. DRIS indices were calculated by the Jones method of the intermediate functions. Index of nutritional balance (INB) was calculated by the average of the sum (disregarding the sign) of all nutritional index values and the dry matter index. Results indicated that, for the conditions of this experiment: (1) DRIS, when compared with the SRA, complements nutritional diagnosis because it establishes an order of deficiency or excess for each nutrient and detects deficiencies or excesses not considered by SRA; (2) There was agreement between the two methods for nutritional diagnosis of K; (3) Cu, Mn, and Fe concentrations were determined as deficient by DRIS, but were classified as adequate or excessive by SRA.  相似文献   

16.
This study investigates the soil–plant nutrient status and relationship in Wolaita, Southern Ethiopia. Maize leaves, soil samples and field history were collected. The result indicated that continuous cultivation without fallowing, complete crop residue removal and inadequate fertilization were common practices. The soil was low in organic carbon, total nitrogen, available phosphorus, potassium, sulfur, boron and copper. Tissue analysis indicated 100, 84, 54 and 28% deficiency of nitrogen, phosphorus, potassium and copper, respectively. Significant and positive correlations (r = 0.70, 0.40 and 0.50) of soil phosphorus, calcium and copper with tissue content were observed. Soil pH was correlated with tissue phosphorus (r = 0.4), iron (r =—0.3) and manganese (r = ?0.7). Overall, the levels of calcium, magnesium, iron, manganese and zinc were adequate for maize. Therefore, fertilizer application addressing nitrogen, phosphorus, potassium and copper deficiencies is recommended for the study area.  相似文献   

17.
鹰嘴蜜桃养分累积分布特性与流胶病的关系   总被引:1,自引:0,他引:1  
在广东省鹰嘴蜜桃产区挖取成熟期中高产鹰嘴桃3株,研究鹰嘴蜜桃的养分累积及分布特性与流胶病发生的关系,并开展鹰嘴蜜桃平衡施肥示范。结果表明,在鹰嘴蜜桃各器官中营养元素含量 N、 Ca、 Mg、 S、 Mn、 Cu、 Zn、 B,以叶片含量最高;Fe、 Mo、 Si含量以根最高;K含量以果肉最高;P含量在叶片、 根和果肉中相差不大。每生产50 kg果实,鹰嘴蜜桃树体(除根系外)需要累积N 2.137 kg、 P 0.184 kg、 K 1.261 kg、 Ca 2.119 kg、 Mg 0.205 kg、 S 0.094 kg、 Si 0.053 kg、 Cu 582 mg、 Zn 10912 mg、 Fe 17847 mg、 Mn 8689 mg、 B 2152 mg、 Mo 20.9 mg。每收获50 kg果实,其带走的养分量为N 0.620 kg、 P 0.077 kg、 K 0.678 kg、 Ca 0.263 kg、 Mg 0.035 kg、 S 0.021 kg、 Si 0.003 kg、 Cu 226 mg、 Zn 1651 mg、 Fe 3601 mg、 Mn 436 mg、 B 958 mg、 Mo 8.8 mg。初步推断出鹰嘴蜜桃流胶病的发生是与其树体K/N低和N/B高有关。通过平衡施肥示范可有效减轻流胶病的发生,明显提高鹰嘴蜜桃果实品质和风味。  相似文献   

18.
A survey was conducted for the nutritional status of aonla orchards in the state of Uttar Pradesh lying in Central Indo-Gangetic plains. Preliminary diagnosis and recommendation integrated system (DRIS) norms were established for different nutrient ratios and used to compute the DRIS indices, which assessed the nutrient balance and order of limitations to yield. Maximum fruit yield of 40.2 kg plant?1 was recorded for the plants at the age group of 10–15 years and lowest yield was recorded 28.3 kg plant?1 in the age of above 20 years. Nutrient sufficiency ranges for aonla derived from DRIS norms were 1.30– 1.64, 0.054–0.092, 0.40–0.64%, and 32.4–45.9 ppm for nitrogen (N), phosphorus (P), potassium (K), and zinc (Zn), respectively. On the basis of these sufficiency ranges 33, 51, 47, and 46% of samples were found sufficient whereas 34, 22, 18 and 27% of samples were low and 26, 8, 1 and 17% deficient in N, P, K, and Zn, respectively. When compared age wise, a relative deficiency for N, P, and K corresponding to relative sufficiency for Zn was detected by DRIS technique for the plants above the age group of 15 onwards. For the younger orchards (5yrs old) a relative deficiency of N, Zn, and K corresponding to the relative sufficiency of P was detected. Nitrogen was found most limiting elements in all age group of plant. When the DRIS indices were compared on basis of soil pH, Zn and K was found to be relatively lesser in order of requirement than N and P.  相似文献   

19.
Diagnosis and Recommendation Integrated System (DRIS) approach was employed to monitor the nutrient status of cotton (Gossipium hirsutum) in southwestern districts of Punjab, North-West India. DRIS norms for macro, secondary and micro nutrients in cotton plant are developed. Considering these DRIS norms, the most limiting nutrient for cotton plant in the region is identified along with the order in which the other nutrients become limiting. The DRIS approach indicated that 11, 3, 8, 5, 2, 4, 2, 3, 6 and 2 percent of the total cotton leaf samples collected were low in nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu), respectively. Leaf tissues of cotton plant were also found to contain high to excessive content of N, P, K, Ca, Mg, S, Fe, Mn Zn and Cu in 11, 7, 15, 19, 25, 18, 66, 33, 9 and 25 percent samples, respectively. DRIS derived sufficiency concentration ranges obtained from survey of cotton fields in this region were 2.22 to 5.20% N, 0.20 to 0.47% P, 1.05 to 2.14% K, 1.66 to 2.86% Ca, 0.34 to 0.57% Mg, 0.65 to 1.11% S, 106 to 172 mg kg?1 Fe, 35 to 68 mg kg?1 Mn, 18 to 33 mg kg?1 Zn, and 5 to 8 mg kg?1 Cu. The results elucidate that DRIS technique can be used for macro, secondary and micro nutrients indexing of cotton crop irrespective of its cultivar.  相似文献   

20.
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   

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