Search

Context: Long-term negative potassium (K) balances in crop production have depleted soil K levels in Western Australia (WA). Previous research has focussed on sand-textured soils, but recently, monitoring of crops grown on loam-textured soils has shown deficient or marginal shoot K concentrations where Colwell K 0–10 cm is above current critical levels. Aims: The aims were to examine whether grain yield responses to fertiliser K can be detected on loam-textured soils and if soil test calibration curves can be identified for these soils. Methods: Eight field trials were conducted with wheat on loam-textured soils. The same experimental design was used at all sites; six levels of K applied at sowing, from 0 to 200 kg K ha−1 with one treatment including a split application. Soil and plant test calibration curves were modelled using measurements from the trials. Key results: Grain yield responses of 0.69 to 1.37 t ha−1 to fertiliser K (P < 0.05) occurred in 4 of 8 trials. Relative yield was closely related to soil exchangeable K and the goodness of fit of the soil test calibration curves increased as the depth of sampling increased. The best soil test calibration curve was for sampling 0–40 cm. Conclusions: This research confirms that on some loam-textured soils, yield loss is occurring to K deficiency if no K fertiliser is applied. Implications: As soil K reserves are run down, soil sampling at 0–40 cm on loam-textured soils will provide the most accurate monitoring of soil K deficiency for wheat production. Long term negative balances for potassium (K) in Western Australia have led to the appearance of K deficiency in crops grown on loam-textured soils. A series of trials confirmed that K deficiency is occurring in wheat grown on these soils and that soil testing to 0–40 cm depth is required to confidently assess the adequacy of soil K supply. Monitoring of shoot K concentration at stem elongation can be used to guide in-season fertiliser K applications. [ABSTRACT FROM AUTHOR]

Chestnuts have always been a marginal fruit crop, and the trees seldom fertilized as a result. Few studies have been devoted to the management of soil fertility and the nutritional status of this crop. This work reports results of soil and plant analyses of a population of respectively 1041 and 198 soil and leaf samples taken across nine municipalities in the district of Bragança, NE Portugal. A second population of 80 soil, leaf and fruit (only 64) samples were taken across the three most productive municipalities in the district of Bragança, from the same orchards, to allow the establishment of relationships between soil fertility parameters and the nutritional status of the trees. The results of the two soil populations showed high soil acidity, low organic matter content, low phosphorus and high potassium content. A high percentage of leaf samples showed concentrations of nutrients below the lower limit of the sufficiency range in both the first and second sample populations, for nitrogen (respectively 63 and 47%), phosphorus (18 and 15%), potassium (34 and 31%), calcium (19 and 52%), magnesium (21 and 13%) and boron (40 and 43%). In the case of boron, 6 and 8% of leaf samples of the first and second populations displayed values within the excessive concentration range. The results of this work also revealed absence or poor relationships between soil properties and/or soil available nutrients and leaf concentration of nutrients. In this crop, therefore, it seems necessary to start applying regular fertilization programs, mainly based on regular evaluation of the nutritional status of trees through leaf analysis. [ABSTRACT FROM AUTHOR]

Boron (B) deficiency hampers cotton (Gossypium hirsutumL.) 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−1and 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−1in recently matured leaves and 38.0 mg kg−1in youngest open leaves; at 60 days old (i.e., at flowering), critical concentration was 55.0 mg kg−1in mature leaves and 43.0 mg kg−1in 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−1in mature leaves and 35.0 mg kg−1in 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. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the optimum time for plant analysis, which can provide useful indications of nutrient deficiencies in plants, and to establish limit values for nutrient supplies to fibre hemp (Cannabis sativa L.). The effect of nutrient supplies on the nutritional status of fibre hemp was estimated by leaf analysis in a long-term field fertilisation experiment at four NPK levels on chernozem meadow soil in Szarvas, Hungary in 1999 (good water supplies) and 2003 (dry). The optimum time for the diagnostic analysis of fibre hemp was found to be late May or early June, when plants in the 5-7-leaf stage are 70-100 cm in height, with a biomass of 2-5 t ha-1 dry matter, depending on water and nutrient supplies, variety and production condition. Nutrient supplies to hemp can be considered satisfactory if plant analysis reveals 5-6 % N, 0.5-0.6 % P and 2.7-3.3 % K in the youngest fully developed leaves in late May. A stem yield (10 % moisture content) of 12-17 t ha-1 was achieved when rainfall supplies were adequate (1999), while in the dry year (2003) the lower nutrient concentrations in the uppermost leaves, indicating nutrient deficiency, resulted in a maximum stem yield of only 6-8 t ha-1. The low, satisfactory and high values for the concentrations of N, P, K, Ca, Mg, Fe, Mn, Zn and Cu reported in the paper could be used to elaborate a fertiliser recommendation system for hemp. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Total concentration is not a reliable indicator of metal phytoavailability in soils. There is a dearth of single universal multielement methods with critical value. Therefore, this study was implemented to select appropriate methods for evaluation of phytoavailable metal status in peaches grown in alkaline alluvial soils. Component plant parts (leaf and fruit flesh and peel) and soil samples were collected from 21 orchards. Fourteen extraction methods were applied to the soils to determine the phytoavailable metal content of the soils. Metal [iron (Fe), manganese (Mn), zinc (Zn), copper (Cu), chromium (Cr), nickel (Ni), cobalt (Co), lead (Pb), and cadmium (Cd)] concentrations in leaf, flesh, and peel samples were assayed, and the relationship was investigated among metals in component parts of the plant. Metals were assayed by various methods to select the most representative method. The methods of aqua regia, Morgan extraction solution, ammonium acetate (NH4OAc; pH 4.8), 0.01 M disodium ethylenediamine-di-o-hydroxyphenylacetic acid (Na2EDDHA), and sodium acetate (NaOAc) + diethylenetriaminepentaacetic acid (DTPA) for Fe and DTPA + triethanolamine (TEA) + calcium chloride (CaCl2), 0.05 N hydrochloric acid (HCl) + 0.025 N sulfuric acid (H2SO4), NH4OAc (pH 4.8), 0.05 M ethylenediaminetetraacetic acid (EDTA; pH 7.0), 0.01 M Na2EDDHA, and 1 M ammonium bicarbonate (NH4HCO3) + 0.005 M DTPA for Ni were well correlated to Fe and Ni in the leaves, respectively. The main factors affecting Fe and Ni availability in the soils were compared with the other methods. Therefore, based on this study, 0.01 M Na2EDDHA should be used for determination of phytoavailable Fe and Ni status in peaches grown on alkaline alluvial soils. Poor correlation was found among the rest of the metals assayed by the methods, concentrations of these metals in component parts of the peach trees, and the examined soil properties. Metal content of the flesh had low correlation coefficients with the examined properties. [ABSTRACT FROM AUTHOR]

Copyright of Latvian Journal of Agronomy / Agronomija Vestis is the property of Latvian Journal of Agronomy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The commercial cultivation of American cranberry (Vaccinium macrocarpon Ait.) in Latvia is mostly developed in high bog territories. American cranberry, fruit indigenous to North America, are characterized as high yielding crop with significantly higher productivity (to 40 t·ha-1) in comparison with wild cranberry (Vaccinium oxycoccos L). Investigations on optimal cultivation and fertilization technologies of cranberry crop appropriate for sphagnum peat are scarce. Therefore studies on mineral nutrition regime of American cranberries and wild cranberries in Latvia are very important. Investigations were done to find out the actual mineral nutrition status of American and wild cranberries in Latvia as well as to evaluate the peculiarities of cranberry mineral nutrition in producing beds and native bogs. 80 (peat and plant) samples were collected from 4 main cranberry producing sites and 3 native bogs during autumn 2004. Plant tissue analysis and soil testing were used to evaluate the cranberry supply with all of the biogenous elements (N, P, K, Ca, Mg, S, Fe, Mn, Zn, Cu, Mo, B). Our results suggest that only 50 % of cranberry producing plantings in Latvia were optimal provided with all of the nutrients. Insufficient level of N, P, S, Cu and Mo, and increased concentrations of Mn as main problems were stated. Although high bogs were characterized as particularly nutrient poor environment, wild cranberries showed high efficiency of Fe, Zn and Mn accumulation. [ABSTRACT FROM AUTHOR]

The networks of 15 international research centers around the globe that are sponsored by the Consultative Group for International Agricultural Research (CGIAR) seeks to alleviate poverty in the developing world through enhanced production, while maintaining biodiversity and the sustainability of natural resources. The mandate of the International Center for Agricultural Research in the Dry Areas (ICARDA) is to focus on improving semi‐arid cropping systems in the drought‐prone West Asia and North Africa region. Since its inception in 1997, ICARDA's soil laboratory played a pivotal role in backstopping the institution's on‐station and on‐farm research in Syria and its collaborative research with the region's national programs. This article gives an overview of the evolution of soil and plant analysis in serving the center's mission. A major effort was the regional soil test calibration program, which set the basis for rational use of fertilizers and the identification of related nutrient constraints. Such analyses were extensively employed in all the long‐term dryland cropping system trials and later in irrigated agriculture and the interface between plant nutrition and crop breeding. Major emphasis was given to improving and upgrading analytical services in the region's laboratories. Despite advances made in analytical methodology, the challenge is to apply to solving real problems in the service of humanity. [ABSTRACT FROM AUTHOR]

The aim of the international organic-nitrogen long-term experiment (Internationaler organischer Stickstoffdauerdüngungsversuch (IOSDV), initiated in 1989) is to compare the effects of different forms of mineral nitrogen fertilizer (0-40-80-120-160 kg N/ha) with different organic amendments (beet leaves, 400 dt/ha; straw, 40 dt/ha; and FYM, 600 dt/ha) on loamy Podzoluvisol (FAO). The ion-exchangeable NH4- nitrogen and NO3- nitrogen content in humus layer and N-content in shoots of different stages of spring barley and spring wheat were studied. Mineral and organic fertilization influenced N-uptake at anthesis and tillering stage. Cereal plants had a sufficient supply of nitrogen at this time. Measured data are well in accordance with published results (Bergmann, 1986). Results of optimal N-content of shoots at different stages correlated positively and significantly with grain yields. Nmin content in the humus layer in autumn was correlated better as in spring with grain yields of spring barley. In the vegetation period, Nmin content correlates better with treatment with mineral nitrogen fertilizer than with use of organic amendments. In addition, yield of spring wheat is significantly correlated with weather conditions. [ABSTRACT FROM AUTHOR]

Increasing crop productivity per unit of land area to meet future food and fiber demand increases both soil nutrient removal and the importance of replenishing soil fertility through efficient nutrient management practices. Significant progress in enhancing nutrient-use efficiency in production agriculture requires improved estimates of plant-available nutrients in the root zone, enhanced crop response to applied nutrients, and reduced offsite nutrient transport. This special issue, Soil Fertility Management for Better Crop Production, presents 15 manuscripts that advance our knowledge of interrelated soil, plant, and management factors important to increasing the nutrient availability and crop recovery of applied nutrients. [ABSTRACT FROM AUTHOR]