Exogenous nitrate induces root branching and inhibits primary root growth in Capsicum chinense Jacq.

The effects of nitrate (NO₃⁻) on the root system are complex and depend on several factors, such as the concentration available to the plant, endogenous nitrogen status and the sensitivity of the species. Though these effects have been widely documented on Arabidopsis and cereals, no reports are ava...

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Detalles Bibliográficos
Autor: ILEANA DE LA CARIDAD ECHEVARRIA MACHADO
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2011
País:México
Institución:Centro de Investigación Científica de Yucatán
Repositorio:Repositorio Institucional CICY
Idioma:inglés
OAI Identifier:oai:cicy.repositorioinstitucional.mx:1003/232
Acceso en línea:http://cicy.repositorioinstitucional.mx/jspui/handle/1003/232
Access Level:acceso abierto
Palabra clave:info:eu-repo/classification/cti/2
info:eu-repo/classification/cti/23
info:eu-repo/classification/cti/2302
info:eu-repo/classification/cti/230221
Descripción
Sumario:The effects of nitrate (NO₃⁻) on the root system are complex and depend on several factors, such as the concentration available to the plant, endogenous nitrogen status and the sensitivity of the species. Though these effects have been widely documented on Arabidopsis and cereals, no reports are available in the Capsicum genus. In this paper, we have determined the effect of an exogenous in vitro application of this nutrient on root growth in habanero pepper (Capsicum chinense Jacq.). Exposure to NO₃⁻ inhibited primary root growth in both, dose- and time-dependent manners. The highest inhibition was attained with 0.1 mM NO₃⁻ between the fourth and fifth days of treatment. Inhibition of primary root growth was observed by exposing the root to both homogeneous and heterogeneous conditions of the nutrient; in contrast, ammonium was not able to induce similar changes. NO₃⁻-induced inhibition of primary root growth was reversed by treating the roots with IAA or NPA, a polar auxin transport inhibitor. Heterogeneous NO₃⁻ application stimulated the formation and elongation of lateral roots in the segment where the nutrient was present, and this response was influenced by exogenous phytohormones. These results demonstrate that habanero pepper responds to NO₃⁻ in a similar fashion to other species with certain particular differences. Therefore, studies in this model could help to elucidate the mechanisms by which roots respond to NO₃⁻ in fluctuating soil environments.