calcareous soils
Recently Published Documents

Organic matter has a positive effect on the uptake of nutrients in the soil. The increase in mycorrhizal activities in the soil causes an increase in the activities in the rhizosphere region. Vermicompost is among the most useful organic fertilizers that can be added to the soil in recent years. Soil microflora is capable of realizing the return of mineral substances. Akkız cowpea variety was used in the study: The experiment was carried out as a viol study with 3 replications according to the randomized blocks trial design. In the study, seedling development was achieved by mixing vermicompost (0, 15, 30 and 45%) with and without mycorrhiza in a soil containing 16% lime into the viols in order to develop seedlings. Sufficient minerals have been applied to the plants for their growth. Seedlings were harvested when they were 40 days old, and seedling measurement parameters and macronutrients in plant leaves were checked. As the amount of vermicompost increased, it caused an increase in the above-ground fresh and dry weights, root fresh and root dry weights of the seedlings. As the organic fertilizer mixture increased, the nitrogen, phosphorus, potassium and magnesium concentrations of the plant leaves increased. The addition of mycorrhiza to the rearing medium has led to different results in the investigated characteristics. Addition of increasing organic fertilizer ratios in the study, Organic fertilizer and bacteria application of cowpea cultivars were effective in increasing the development of plants in calcareous soils.

Determination of soil cation exchange capacity (CEC) in lab is cumbersome, time consuming, and costly. Accordingly, this article attempted to formulate pedotransfer functions for predicting it using some soil physical and chemical properties e.g., sand (SA), silt (SI), clay (CL), organic matter (OM) and calcium carbonate (CC). This research included four steps: preparing soil database; selecting independent variables which are related to CEC value; formulating models using NCSS 12.0.2 software, and the last step is to achieve specific objective of the research which is the comparsion among models by a series of efficiency criteria: root mean square error (RMSE), Nash-Sutcliffe model efficiency coefficient (EF), average absolute percent error (AAPE), and percentage of improving model efficiency (PIME). The statistical results of the research indicated that CEC of calcareous soils could be predicted from models that have one variable (CL), two variables (CL and OM), and three variables (CL, OM, and CC) with slight decrease in the RMSE (2.95402, 2.81180, and 2.79268) respectively, and slight increase in the EF (0.887360, 0.898448, and 0.90023) respectively. While the reliable models to predict soil CEC are formulated from the fewer number of independent variables with having the lowest points of the standardized residual of CEC that greater than +2 cmolc kg-1).

Understanding the dynamics of potassium (K) and its availability is fundamental in its efficient use as an important nutrient. The objectives of present study were to compare standard K extraction methods for extractable K and kinetics of K adsorption on five different textured soils. The soils were analyzed for physico-chemical properties, extractable K contents and kinetics of K adsorption. The soils had variable contents of soluble (8-52mg kg-1), exchangeable (13-215mg kg-1), fixed (488-1836mg kg-1), structural (2936-26362mg kg-1) and total K (3438-28517mg kg-1). Except soluble K, the amount of K in different forms was significantly (P?0.05) correlated with clay contents, electrical conductivity (EC), cation exchange capacity (CEC) and calcium carbonate in soils. Different methods variated the extracted K in different textured soils. Mehlich-III, ammonium acetate, AB-DTPA, and calcium chloride extracted K was maximum in sandy clay loam (298mg kg-1, 267mg kg?1, 226mg kg-1, and 113mg kg-1) and lowest was in loamy sand (33mg kg-1, 24mg  kg-1, 30mg kg-1, and 24mg   kg-1) respectively. Elovich and power function models best explained the K kinetics adsorption, as rate of adsorption constants were negatively correlated with sand contents in the soil type. Pearson correlation showed that the extractability of K by different methods and kinetics of K adsorption were dependent on soil texture EC, CEC and calcium carbonate contents. Hence, soil physico-chemical properties should be considered in recommending rate of K fertilization along with crop K demand and soil extractable K.

Abstract Purpose Alkaline salinity constrains crop yield. Previously, we found local adaptation of Arabidopsis thaliana demes to saline-siliceous soils (pH≤7) and to non-saline carbonate soils. However, any natural population of A. thaliana was localized on saline-alkaline soils. This suggests that salinity tolerance evolved on saline-siliceous soils may not confer tolerance to alkaline salinity. This hypothesis was explored by addressing physiological and molecular responses to saline-alkaline conditions of A. thaliana demes differing in salinity and carbonate tolerance.Methods A. thaliana native to saline-siliceous soils (G3), to non-saline carbonate soils (G1), or to soils with intermediate levels of these factors (G2) were cultivated in common gardens on saline-siliceous or saline-calcareous substrate. Hydroponics and irrigation experiments confirmed the phenotypes. Growth, mineral concentrations, genome differences, and expression of candidate genes were assessed in the different groups.Results G3 performed best on saline-siliceous soil and in hydroponics with salinity (pH 5.9). However, G3 was more sensitive to saline-alkaline conditions than G1 and G2. Fitness under saline-alkaline conditions was G2 > G1>G3 and G2 best maintained ion homeostasis under alkaline salinity. Whole genome scan did not differentiate among the groups, while distinctive patterns for FRO2, NINJA, and CCB4 were found and confirmed by qPCR.Conclusion In A. thaliana, salinity tolerance evolved on saline-siliceous soils does not provide tolerance to alkaline salinity. Plants from soils with intermediate conditions (G2) have more plasticity to adapt to alkaline salinity than those locally adapted to these individual stress factors. Higher expression of NINJA and CCB4 may contribute to this better adaptation.