Loading...
Thumbnail Image

Theses

Browse

Search Results

Now showing 1 - 1 of 1
  • ThesisItemOpen Access
    Characterizing Rooting Behaviours of Chickpea (Cicer arietinum, L.) and Wheat (Triticum aestivum, L.) Crops under Different Soil Compaction Levels
    (JNKVV, 2013) Choudhary, Kalu; Rawat, A.K.
    ABSTRACT The plant roots, popularly known as “hidden half” of plants are responsible for anchorage, supply the plants with water and nutrients, and exchange various growth substances with the shoots. Root traits such as root length, root depth, root diameter and biomass have been identified as most promising plant traits as these help in greater extraction of water and nutrients from soil. Plant roots are strongly affected by physical factors in soil such as mechanical impedance, caused mainly by natural processes as well as by the use of heavy machinery in soil cultivation. In the present investigation, a laboratory experiment was undertaken at Indian institute of soil science, Bhopal, India, to study the effect of different compaction levels on plant growth and various root parameters such as root length, root mass, no.of nodes, primary roots, main axis length and insertion angle and to understand the dynamic of rooting behavior of the two most important crop of central India i.e. Chickpea (Cicer arietinum L.) and Wheat (Triticum aestivum L.). Different soil compaction levels viz., bulk density (BD) (i) 1.2 (ii) 1.4 (iii) 1.5 and (iv) 1.6 Mg m-3 were taken for this study. The data were analysed according two factor CRD with crop cultivars as the main factor, compaction level (i.e. BD) as the subplot factors. Result showed that the plant height and root length of chickpea and wheat cultivar decreased with increased bulk density. Between two cultivars of chickpea, root length, root biomass, main axis length, no.of primary axis, insertion angle and no. of nodes were found greater in JG130 compared to JG11. And similar results were also obtained in case of wheat, cultivar Malwa Shakti as compared to Sujata. When the BD was increased from 1.2 Mg m-3 to 1.6 Mg m-3, there was 58% and 44% reduction in plant height of cv JG 11 and JG 130, respectively. Similarly, when the BD was increased from 1.2 Mg m-3 to 1.6 Mg m-3, there was 27% and 24% reduction in plant height of cv Sujata and Malwa Shakti, respectively. There was 59% and 45% reduction in root length of cv JG 11 and JG 130, with increase in BD from 1.2 Mg m-3 to 1.6 Mg m-3. Similarly there was 49% and 48% reduction in root length of cv Sujata and Malwa Shakti, with increase in BD. There was a negative correlation between root penetration rate and soil bulk density (R2 = 0.88 for chickpea, 0.86 for wheat and 0.77 overall). The critical growth limiting bulk densities for chickpea and wheat are considered to be 1.76 Mg m-3 and 1.89 Mg m-3, respectively. The overall critical bulk density for both the crop was found to be 1.82 Mg m-3. In this study the pattern of observed root length was fitted with the logistic growth model. The model fitted well with the observed dataset obtained from both cultivars of chickpea and wheat with a R2 of 0.98** (p = 0.01). The root characteristics and morphologies studied served as the criteria for selection of crop cultivars suitable for compaction studies. In this study the chickpea variety JG 130 and wheat cultivar Malwa Shakti proved to be better options while selecting chickpea and wheat cultivars for highly compacted soils