Research Articles
Phosphorus Mobilizing Capacity of Selected Grain Legumes Grown Under Phosphorus-Deficient Conditions
Authors:
T. G. R. M. Thennegedara,
University of Peradeniya, Peradeniya, LK
About T. G. R. M.
Department of Crop Science, Faculty of Agriculture
D. M. S. B. Dissanayaka
University of Peradeniya, Peradeniya, LK
About D. M. S. B.
Department of Crop Science, Faculty of Agriculture
Abstract
Compared with other crops, legumes have superior ability to mobilize part of non-labile phosphorus (P) into labile/available forms. We explored the P-mobilization potential of selected grain legumes and its influence on growth, P uptake, and yield under P-deficient conditions. A pot experiment was carried out in a greenhouse with soybean (Glycine max L.), cowpea (Vigna unguiculata L.), green gram (Vigna radiata L.), and black gram (Vigna mungo L.) with two P fertilizer applications; without (Pdeficient) and with (P-sufficient) Department of Agriculture recommended rates of triple super phosphate. Each crop was harvested at maturity and the bulk and rhizosphere soils were collected to quantify different P fractions using Hedley’s sequential fractionation. Dry weight and P accumulation in different plant organs, i.e. roots, stems, leaves, and pods, were measured. Most plant organs maintained similar dry weight and tissue-P concentration irrespective of the P levels applied. All crops reduced their total plant-P uptake under P-deficient conditions. However, this did not make any change in either pod dry weight or P concentration of pods. Soybean and mung bean had a greater P accumulation compared to cowpea and black gram under both P levels. In contrast, cowpea and black gram showed improved P use efficiency (PUE) than other two legumes. Available P concentration (NaHCO3-P) in rhizosphere soil is greater than that in bulk soil in soybean and cowpea whereas the rhizosphere NaHCO3-P content in mung bean was greatly decreased compared to that of bulk soil when the crop was cultivated in P-deficient soil. The concentration of non-labile P fraction in rhizosphere of all grain legumes were significantly low compared to that of the bulk soil. Results suggest that selected grain legumes could be cultivated in P-deficient soil as they can adapt either through enhancing P uptake or increasing PUE.
How to Cite:
Thennegedara, T.G.R.M. and Dissanayaka, D.M.S.B., 2021. Phosphorus Mobilizing Capacity of Selected Grain Legumes Grown Under Phosphorus-Deficient Conditions. Tropical Agricultural Research, 32(4), pp.380–389. DOI: http://doi.org/10.4038/tar.v32i4.8413
Published on
01 Oct 2021.
Peer Reviewed
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