Carbon and nitrogen assimilation, and growth of moongbean (Vigna radiata [L.] Wilczek) cultivars grown under sulfur regimes

• Published in: Archiv für Acker- und Pflanzenbau und Bodenkunde 2009-04, Vol.55 (2), p.207-215
• Main Authors: Anjum, Naser A., Umar, Shahid, Iqbal, Muhammad, Khan, Nafees A.
• Format: Article
• Language: English
• Subjects: carbon and nitrogen assimilation; moongbean; nitrate reductase activity; photosynthesis; sulfur regimes
• ISSN: 0365-0340; 1476-3567
• DOI: 10.1080/03650340802350626

Sulfur (S) has become an essential macronutrient for plants but its deficiency in agricultural soil is increasing worldwide. In a greenhouse pot-experiment the influence of S availability (0 and 40 mg S kg −1 soil) on some growth and physiological attributes and their relationships was determined in two cultivars (Pusa 9531 and PS 16) of moongbean (Vigna radiata [L.] Wilczek) at 20 and 40 days after sowing (DAS). Sulfur deficiency translated as decreased plant dry mass (PDM), leaf area (LA), net photosynthesis (P N ), nitrate reductase activity (NRA), contents of chlorophyll (Chl), soluble protein and leaf sulfate (SO 4 2− ). These changes were in correspondence with significant increase in contents of leaf nitrate (NO 3 − ) and free amino acids being more pronounced in cultivar PS 16 than Pusa 9531. The relationship of NRA with plant dry mass and P N was worked out in both cultivars. Pusa 9531 significantly maintained the coordination between C and N assimilation and hence, the plant growth under S-deficient condition. The information may be useful in breeding moongbean cultivars.