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1.
Abstract

Individual peach [Prunus persica (L.) Batsch] trees were monitored prior to the development of peach tree short life (PTSL) to determine if nutrient deficiencies and/or imbalances were causative factors in PTSL development. Twig concentrations of Al, Ca, Fe, K, Mg, Mn, P, and Zn were determined in March and December of each year. In the final year of the study, elemental concentrations were also determined in April after visual symptoms of PTSL were evident. Elemental concentrations in healthy trees were compared to concentrations in trees which eventually died due to PTSL. Significant differences in P and K concentrations between PTSL and healthy trees were found in 1986 and 1987 but no consistent trends were apparent. The greatest differences between PTSL and healthy trees were found after visual symptoms of PTSL appeared. In most cases, elemental concentrations were greater in trees exhibiting PTSL symptoms than in healthy trees. The data indicate that differences were symptoms of the PTSL complex and not a cause in the development of the disease.  相似文献   

2.
Seedlings of ‘Lovell’ peach [Prunus persica (L.) Batsch], and in vitro propagated plums, ‘St. Julien A GF 655–2’ [Prunus institia (L.) Bullace] (655–2), ‘Damas GF 1869’ [Prunus domestica (L.)] (D1869), and ‘Clark Hill Red Leaf’ [Prunus saliciana (Lindl) x Prunus cerasifera (EHRH)] (CH redleaf) were grown in the greenhouse 45 or 51 days in nutrient solutions containing 2, 6, 22, 200, and 400 μM Ca. Terminal length, number of laterals, trunk cross‐sectional area, and root volume were increased by the 22 μM Ca treatments at harvest 1. The CH redleaf and 655–2 plums had the largest increase in growth for harvest 1, but the ‘Lovell’ peach seedlings and D1869 plum had the largest increase in growth for harvest 2. There were no leaf symptoms of Ca deficiency when the leaf Ca concentration in the tissue exceeded 2500 μg/g (dry wt.) Calcium concentration was increased from 1406 to 4109 μg/g (dry wt.) in the stems, and from 540 to 2633 μg/g (dry wt) in the roots by Ca treatments of 400 μM after 45 days of growth. Calcium uptake rate for ‘Lovell’ seedlings was greater than were rates for CH redleaf and 655–2 plums at all solution concentrations during the first 45 days of growth. The Ca uptake rate for D1869 plum was greater than the rate for ‘Lovell’ seedlings during the second growth period. An interaction between Ca concentration and plant species occurred for P, K, and Mg uptake rates at both harvest dates. The in vitro propagated D1869 plum was equal to the ‘Lovell’ seedlings in growth, tissue Ca concentration, and Ca uptake rates.  相似文献   

3.
Soils of the peach growing region of the Southeastern Coastal Plain are highly leached and excessively acid, with inherently low concentrations of subsoil magnesium (Mg). A greenhouse experiment was conducted to determine the effects of varying Mg concentrations at low pH on growth and Mg uptake of three peach seedling cultivars commonly used as rootstock in the region. Seedlings of ‘Lovell’, ‘Elberta’, [Prunus persica (L.) Batsch] and ‘Nemaguard’ [Prunus persica (L.) Batsch X Prunus davidiana Carriere] were grown for 36 days in nutrient solution containing 9, 21, 42, 84, 167, 333, and 667 μM Mg. Magnesium concentration in solution did not increase lateral length, number of laterals, trunk cross‐sectional area, or root volume. All terminal growth responses were cultivar related. Magnesium concentration in the leaves, stems, and roots were increased either by quadratic or cubic relationship with solution Mg concentration while Mg uptake rate was increased linearly with solution Mg concentration with all three seedling cultivar. Uptake rates of calcium, manganese, and zinc, and tissue concentrations of phosphorus, manganese, and zinc decreased with increasing Mg concentrations in nutrient solution. Predicted Mg uptake rates by‐regression analysis revealed a cubic uptake isotherm for Nemaguard and a quadratic isotherm for Elberta. Predicted tissue Mg concentration followed similar patterns of accumulation for leaves and stems, but root Mg concentration followed a cubic uptake isotherm for all three seedlings. The linear Mg uptake at low pH may be an important physiological characteristic that enables Lovell seedlings to outperform either Elberta or Nemaguard when used as a rootstock in the southeastern soils.  相似文献   

4.
Abstract

Some problem areas connected with soil testing and with reporting soil test and plant analysis results are explored, A uniform system for reporting soil test results is suggested as a step towards further standardization of soil test methods within and among states. Four categories are suggested as a common terminology for soil test and plant analysis results. These are: deficient, probable response, adequate and excessive.  相似文献   

5.
Abstract

A rapid colorimetric method for the determination of boron in soil extracts, plant materials, composts, manures, water and nutrient solution is proposed. The method is rapid, reliable and carried out in aqueous solution. A marked advantage is that boron can be determined in the same soil extract or plant material digest used for determination of other elements.  相似文献   

6.
Abstract

We studied the effects of liming on dry matter production, nutrient composition, and grain yields of wheat in field experiments conducted on two soil types at three locations during the 1976–77 and 1977–78 growing seasons. Lime sources were commercial agricultural lime, finely divided stack dust, and dolomitic limestone (which contained 10.6% Mg). Lime applied at 2,800 kg/ha in the 1976–77 and 10,750 kg/ha in the 1977–78 experiments provided Mg from the dolomite at rates of 300 and 1,140 kg/ha, respectively.

Soil pH was significantly increased by liming, but Mg saturation percentages were significantly greater only at the 1,140 kg/ha rate. Forage dry matter and grain yields were not increased by lime applied at the lower rate, but significant increases were found in dry‐matter production in the late fall and spring samplings of the 1977–78 experiment. Those increases in plant growth and dry matter production were probably due to reductions in the soluble Mn and Al concentrations in the soil. Forage N and P concentrations were generally not influenced by liming. Potassium concentrations in forage from the limed plots were usually equal to or greater than those in forage from unlimed plots. Calcitic limestone sources generally increased forage Ca concentrations, but liming with dolomite more often than not depressed Ca concentrations below levels found in the check plots. Dolomite, when applied at the 1,140 kg/ha rate, effectively increased the forage Mg concentration, although the concentration exceeded 0.2% only during the early growth stages. Liming generally showed no significant reduction in the tetany potential of the wheat forage as predicted by the equivalent ratio K/(Ca + Mg).  相似文献   

7.
Abstract

Agricultural Experiment Station researchers can and have played a primary role in the development of the soil testing and plant analysis techniques. Analytical methodology has far outdistanced our ability to use effectively the results of these tests and analyses. Continued research is needed to establish more effective methods of interpreting and utilizing results to prevent or correct uncovered nutrient element deficiencies.  相似文献   

8.
The aim of the present experiment was to evaluate the effect of commercial Trichoderma and arbuscular mycorrhizal fungi (AMF)-based bio-fertilizers on nectarine root growth, nutrient acquisition and replanting disease. The experiment was performed from 2008 to 2012 in an A. mellea-infected nectarine orchard subjected to the following treatments: 1) untreated control; 2) AMF-biofertilizer applied at planting (120 kg ha?1) and every year in spring and autumn at the rate of 6 kg ha?1; 3) Trichoderma spp applied at planting (5 g plant?1) and every year (in April, May and September) at 2.5 kg ha?1. AMF bio-fertilizers decreased root diameter and increased root survivorship. Leaf phosphorus concentration increased in AMF bio-fertilizers plots, while no significant treatments effects were observed on other leaf nutrient concentration. Although biofertilizer application did not affect soil microbial population, at the end of the trial (2012) the application of Trichoderma alone increased the population of the fungus.  相似文献   

9.
Abstract

Six cultivars and three lines of soybean (Glycine max (L.) Merr.) were planted at two locations in Delaware in 1974 and 1975. Potassium fertilizer (KCl) at 0, 56, or 223 kg/ha actual K was added to the soil and the plants were evaluated for seed yield and incidence of gray‐moldy and purple‐stained seed.

Potassium application was related to a decrease in yield in one year at one location but had no significant effect in the other year or at the other location. Cultivars differed in yield over the two years, with Kent, Cutler 71, and York having the most consistent yield in this study. The pathogen incidence was not affected by potassium application in contrast to earlier studies with soybeans grown in aluminum cylinders with a partially restricted soil volume. In this study, gray‐moldy and purple‐stain was highest in short season cultivars and higher at Georgetown than at Newark.

Use of soybean cultivars resistant to diseases as well as maintaining adequate soil potassium levels should reduce high levels of disease.  相似文献   

10.
Abstract

A study was made of the comparative nutrient content of healthy and declining sweet orange trees. Leaves were analysed for 12 elements using Kjeldahl and Spectrographic methods. No statistical differences were observed between healthy and declining trees in their content of N, P, Mg, Na, Mn, Fe, B, Cu, Mo, and Zn. Significant differences were obtained for K and Ca; healthy Blood Red trees were found to be lower in K but higher in Ca than declining trees. Phosphorus content was observed to be borderline to low in both healthy and declining trees. Magnesium was low to deficient. Boron content was high to excessive in most orchards regardless of tree condition.  相似文献   

11.
Interest in mixed‐species plantations in the tropics has increased because they appear to provide a wider range of options, such as yield, biodiversity, nutrient cycling, and C sequestration than pure stands. Pure stands of Pinus patula Schlecht. and Charm., Juniperus procera Hochst., and Grevillea robusta A. Cunn., and mixed stands of P. patula/G. robusta, P. patula/J. procera, and P. patula/Podocarpus falcatus R. Br. at Wondo Genet in S Ethiopia were studied to examine (1) the impact of mixed‐species plantations on soil chemical properties, and (2) the impact of mixed‐species plantations on the nutritional status of constituent trees. Soil (0–50 cm depth) and foliage samples were collected from four random plots (100 m2) in each of the pure and mixed‐species plantations. Soil samples were analyzed for organic C, N, and base cations. Foliage samples were analyzed for nutrients (N, P, K, Ca, and Mg). There were little significant differences in soil chemical properties and foliar nutrient concentrations of trees between the pure and mixed stands. Among pure stands, J. procera and G. robusta differed in soil exchangeable Ca++ and K+ at 0–5 cm soil depth and in foliar P and Ca concentration. After 18 and 24 y, mixed stands did not influence soil chemical properties and tree nutrition differently than pure stands. This may be due to additive interaction in mixed‐species stands and the similarity of the constituent tree species in foliar nutrient concentration and their impact on soil chemical properties.  相似文献   

12.
Efficient nutrient utilization by plants is extremely important in developing countries and is becoming more important in the developed countries as the costs of fertilizers are increasing. Pearl millet is a world food and forage crop usually grown on droughty soils low in nutrients. Eighty‐five genetically diverse pearl millet, Pennisetum glaucum (L.) R. Br. lines were grown in low Mg and K sand for three weeks to screen for efficient Mg uptake. Magnesium free Hoagland's solution at one‐fourth strength was used to water the plants as needed. Forage produced was clipped, dried, ground, ashed, and analyzed for Mg and K content. A 2‐fold difference for Mg concentration in the forage existed among the lines. The data indicated that a low [K]/[Mg] ratio in the plant was indicative of a Mg efficient genotype. The data also suggest that caution should be used in making general nutrient recommendations based on tissue or soil tests without knowing the nutrient requirement of the cultivar.  相似文献   

13.
pp. 875–880

The trace-element composition of kernel in pickled Japanese apricot (Prunus mume Sieb. et Zucc.) was determined using an inductively coupled plasma optical emission spectrometer in order to distinguish between Japanese products and Chinese products.

Strontium and barium concentrations in the kernels of Chinese products were 10 or more times those of the Japanese ones. When based on 8.0 mg kg?1 of strontium concentration in kernel, 93.2% of sample was distinguished as Japanese products or Chinese ones.

Applying principal component analysis using 9 elements (Mn, Zn, Fe, Ni, Ba, Sr, Cu, Co, Cr), the pickled Japanese apricots tend to separate into two countries. Linear discriminant analysis (LDA) using 9 elements allowed a reasonable classification of pickled Japanese apricots according to the country of production.

The result of the analysis of K-nearest neighbors (KNN) was better than that of LDA.  相似文献   

14.
Soil and plant analysis has been a major contribution to the development of the agricultural sciences and indirectly to sustaining mankind. The advances that have occurred in the various disciplines in soil science, agronomy, and crop science would have been impossible without parallel advances in analytical technology. Despite the many divisions in the journals of the Soil Science Society of America, Crop Science Society of America, and American Society of Agronomy, none is solely devoted to the discipline of analysis of soils and plants and related areas. However, the Soil and Plant Analysis Council (SPAC) fills that critical void because it is an international society of scientists, educators, and private and public organizations with a common interest in promoting analysis of soils, plants, water, manure, and fertilizers. The primary emphasis is on nutrients in relation to crop production and increasing environmental issues. The main goal of SPAC is to provide leadership in the development and dissemination of methodology, interpretation, and application of analysis for efficient resource management and environmental protection. Its activities include publications (methods handbooks, symposia and workshop proceedings, newsletter), liaising with national agencies and commercial organizations to standardize and improve analytical procedures, maintenance of a laboratory directory, and holding international symposia. The Council has played a significant role in expanding the breadth, depth, and scope of analytical technologies in North America as well as internationally.  相似文献   

15.
Boron (B) deficiency hampers cotton (Gossypium hirsutum L.) growth and productivity globally, especially in calcareous soils. The crop is known as a heavy feeder of B; however, its reported plant analysis diagnostic norms for B-deficiency diagnosis vary drastically. In a 2-year field experiment on a B-deficient [hydrochloric acid (HCl)–extractable 0.47 mg B kg?1], calcareous, Typic Haplocambid, we studied the impact of soil-applied B on cotton (cv. CIM-473) growth, productivity, plant tissue B concentration, and seed oil composition. Boron was applied at 0.0, 1.0, 1.5, 2.0, 2.5, and 3.0 kg B ha?1, as borax (Na2B4O7·10H2O), in a randomized complete block design with four replications, along with recommended rates of nitrogen (N), phosphorus (P), potassium (K), and zinc (Zn). Boron use improved crop growth, decreased fruit shedding, and increased boll weight, leading to seed cotton yield increases up to 14.7% (P < 0.05). Improved B nutrition of plants also enhanced seed oil content (P < 0.05) and increased seed protein content (P < 0.05). Fiber quality was not affected. Fertilizer B use was highly cost-effective, with a value–cost ratio of 12.3:1 at 1 kg B ha?1. Fertilizer B requirement for near-maximum (95% of maximum) seed cotton yield was 1.1 kg B ha?1 and HCl-extractable soil B requirement for was 0.52 kg ha?1. Leaf tissue B requirement varied with leaf age as well as with plant age. In 30-day plants (i.e., at squaring), B-deficiency diagnosis critical level was 45.0 mg kg?1 in recently matured leaves and 38.0 mg kg?1 in youngest open leaves; at 60 days old (i.e., at flowering), critical concentration was 55.0 mg kg?1 in mature leaves and 43.0 mg kg?1 in youngest leaves. With advancement in plant age critical B concentration decreased in both leaf tissues; that is, in 90-day-old plants (i.e., at boll formation) it was 43.0 mg kg?1 in mature leaves and 35.0 mg kg?1 in the youngest leaves. As critical concentration range was narrower in youngest leaves (i.e., 35–43 mg kg?1) compared with mature leaves (i.e., 43–55 mg kg?1), B concentration in youngest leaves is considered a better indicator for deficiency diagnosis.  相似文献   

16.
Leaves of olive (Olea europaea var. minor rotunda) were collected from mature non-irrigated trees in an “off” year, at monthly intervals, from May 2015 to April 2016. Leaf concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), manganese (Mn), zinc (Zn) and boron (B) were determined. Seasonal fluctuation curves were developed for each nutrient, in order to use them for interpretation of leaf analysis. Concentrations of N, P, K, Ca and Mg showed significant fluctuation throughout the year, while B, Fe, Mn and Zn showed less intense changes. Nutrient accumulation varied according to tree vegetative growth and weather conditions.  相似文献   

17.
The labile organic carbon(C) and C-related enzymes are sensitive indicators capturing alterations of soil organic matter(SOM),even in a short-time scale.Although the effects of crop husbandry and land use change on these attributes have been well studied,there is no consensus about how plant phenology may impact them.This study aimed to determine the short-term effect of six distinct phenological stages(PS-1:full bloom;PS-2:fruit set;PS-3:pit hardening;PS-4:physiological maturity;PS-5:60 d after physiological maturity;and PS-6:fall) of peach on the changes in soil organic carbon(SOC) fractions of different oxidizability,labile C pools,and C-cycle enzyme activities in soils,for two consecutive years(2015 and 2016) in the North-Western Himalayas(NWH).Peach rhizosphere soils were sampled at the topsoil(0–15 cm) and subsoil(16–30 cm) layers,along with rhizosphere soils from adjacent perennial grasses,which served as a control.Values for most of the assessed parameters,including very labile C,labile C,microbial biomass C,permanganate oxidizable C,dissolved organic C,mineralizable C,amylase activity,and carboxymethyl-cellulase activity,were significantly(P ≤ 0.05) higher at PS-3 than at other phenological stages of peach.Conversely,a sudden decline in these soil variables was recorded at PS-5,followed by a slight buildup at PS-6,particularly in the topsoil of the peach orchard.Short-term changes in organic C fractions of different oxidizability,influenced by peach phenological stage,significantly(P ≤ 0.05) affected C management index,C pool index,and lability index.Both the C management index and lability index showed their highest values at PS-3 and their lowest values at PS-5,clearly indicating short-term accretion and depletion of SOC,in tandem with the peach phenological events.Principal component analysis suggested that a composite of soil indicators,including microbial biomass C,dissolved organic C,amylase,and invertase,could help detect short-term changes in SOC content.It is concluded that peach phenological events had a major impact on the short-term variations of the studied soil variables,which could be attributed to changes in the above-and belowground plant residues,as well as the extent of nutrients and water acquisition.  相似文献   

18.
Abstract

Eradication and surveillance zones for red imported fire ant (Solenopsis invicta) embrace parts of southeastern Queensland, Australia. To lessen the risk of fire ants becoming established at new locations, those who transport soil and plant materials from affected areas for commercial reasons must comply with official risk‐management measures. This obligation is one of many that soil and plant testing laboratories in different Australian states now have a legal requirement to manage, whether samples come from within the state, interstate, or overseas. Many examples of pests and diseases of concern are provided, along with information on current pest‐management regulations. Annual soil and plant sample transactions for years 2001–2003 suggest that the regions at most risk from accidental pest and disease movement are in this order: Western Australia>Queensland>New South Wales. Large laboratories in particular are encouraged to implement a hazard analysis and critical control point (HACCP) evaluation of their sample‐handling procedures from receipt to disposal. Staff training in pest and disease awareness and recognition during all aspects of soil and plant analysis is encouraged.  相似文献   

19.
ABSTRACT

Calibration of field crop responses to nutrient availability acts as a basis for making fertilizer recommendations from soil and tissue analysis. The purpose of this study was to evaluate and summarize silicon (Si) fertilization of rice in different soils of south India. The experiment consists of four levels of calcium silicate as Si with three replications. Initially, soils were analyzed using eleven different extractants. The grain and straw yield were recorded and analyzed for Si content. The critical levels for plant available Si in the soil ranged from 14 mg kg?1 (distilled water-1) to 207 mg kg?1 [0.005 M sulfuric acid (H2SO4)]. There was a wide variation in low, medium, and high categories of plant available Si for different extractants calculated based on percent relative yield. The critical level of Si in straw and grain were 2.9 and 1.2%, respectively.  相似文献   

20.
Abstract

Methods are proposed for the determination of cadmium in soils, plants and fertilizers.

Soil is first dissolved by treatment with hydrofluoric and hydrochloric acids and plant material is digested with nitric‐perchloric‐sulphuric acids. The cadmium is then extracted from the resulting solutions as the dithizone complex. After destruction of the dithizone the cadmium is dissolved in dilute hydrochloric acid and determined by atomic absorption spectroscopy. Cadmium in phosphatic fertilizers is determined directly by atomic absorption measurement on hydrochloric acid digests of the fertilizer.

The proposed methods have precision adequate for the study of cadmium in soil‐plant systems, the limits of detection being: plant material, 0.004 ppm Cd; soils, 0.02 ppm; and phosphatic fertilizers, 1 ppm.  相似文献   

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