Nitrate regulates rhizobial and mycorrhizal symbiosis in common bean (Phaseolus vulgaris L.). Issue 3 (25th February 2014)

• Record Type: Journal Article
• Authors: Nanjareddy, Kalpana; Blanco, Lourdes; Arthikala, Manoj‐Kumar; Affantrange, Xochitl Alvarado; Sánchez, Federico; Lara, Miguel
• Is Part Of: Journal of integrative plant biology. Volume 56:Issue 3(2014)
• Page Start: 281
• Page End: 298
• Publication Date: 2014-02-25
• Subjects: Plants -- Periodicals; Plants -- China -- Periodicals; Electronic journals; 580.5
• DOI: 10.1111/jipb.12156
• Languages: English
• ISSNs: 1672-9072

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <sec id="jipb12156-sec-0001" sec-type="section"> <p>Nitrogen‐limited conditions are considered to be a prerequisite for legume‐rhizobial symbiosis, but the effects of nitrate‐rich conditions on symbiotic status remain poorly understood. We addressed this issue by examining rhizobial (<italic>Rhizobim tropici</italic>) and arbusclar mycorrhizal (<italic>Glomus intraradices</italic>) symbiosis in <italic>Phaseolus vulgaris</italic> L. <italic>cv</italic>. <italic>Negro Jamapa</italic> under nitrate pre‐incubation and continuous nitrate conditions. Our results indicate that nitrate pre‐incubation, independent of the concentration, did not affect nodule development. However, the continuous supply of nitrate at high concentrations impaired nodule maturation and nodule numbers. Low nitrate conditions, in addition to positively regulating nodule number, biomass, and nitrogenase activity, also extended the span of nitrogen‐fixing activity. By contrast, for arbuscular mycorrhizae, continuous 10 and 50 mmol/L nitrate increased the percent root length colonization, concomitantly reduced arbuscule size, and enhanced ammonia transport without affecting phosphate transport. Therefore, in this manuscript, we have proposed the importance of nitrate as a positive regulator in promoting both rhizobial and mycorrhizal symbiosis in the common bean.</p> </sec> </abstract>