Influence of Boron Nutrition on Membrane Leakage,Chlorophyll Content and Gas Exchange Characteristics in Cotton (Gossypium Hirsutum L.) |
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Authors: | N Ahmed A Rashid R Abou-Shanab F Ahmad |
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Institution: | 1. Department of Soil Science, Faculty of Agricultural Sciences &2. Technology, Bahauddin Zakariya University, Multan, Pakistan;3. Bio-Sciences Division, Pakistan Atomic Energy Commission, Islamabad, Pakistan;4. Department of Environmental Biotechnology, City of Scientific Research and Technology Application, Alexandria, Egypt;5. Central Cotton Research Institute, Multan, Pakistan |
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Abstract: | Understanding the effect of boron (B) on plant physiology will help to refine the diagnosis of B deficiency and improvement in B fertilizer recommendations for cotton (Gossypium hirsutum L.) growing areas. This study shows the testing of hypotheses “that application of B-fertilizer improves net photosynthetic rate (PN) and water use efficiency (WUE) for cotton plant on a B-deficient soil < 0.50 mg B kg?1 hydrochloric acid (HCl)-extractable] in an arid environment”. Thus, a permanent layout two-year field experiment (2004 and 2005)] was conducted to study the impact of B fertilizer at 0, 1.0, 1.5, 2.0, 2.5, and 3.0 kg ha?1 on gas exchange and electrolyte leakage (EL) characteristics of cotton crop (cv. ‘CIM-473’). The soil at experimental site was alkaline (pH 8.1), calcareous calcium carbonate (CaCO3 5.6%)], and silt loam (Typic Haplocambid). Boron use decreased EL of plant membrane (P ≤ 0.05), and increased PN, transpiration rate (E) and stomatal conductance (gs), while intercellular concentration of carbon dioxide (CO2; Ci) significantly decreased (P ≤ 0.05) during both experimental years. There was a positive, but non-significant effect of B concentration on chlorophyll content in plant leaves. Application of 3.0 kg B ha?1 improved WUE up to 9.7% 4.62 μmol (CO2) mmol?1 water (H2O)] compared to control plants (4.21 μmol (CO2) mmol?1 (H2O)]. Principal component analysis (PCA) of data indicates positive correlations between leaf B concentration and PN, E, gs, and WUE, while a negative relationship existed between leaf B concentration and intercellular CO2 (Ci). This study showed that addition of B fertilizer in the B-deficient calcareous soil proved beneficial for growth and development for cotton crop by enhancing its WUE and gas exchange characteristics. |
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Keywords: | boron nutrition Gossypium hirsutum L electrolyte leakage photosynthetic rate water use efficiency calcareous soil |
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