Data/hora: 13/06/2024 03:47:19

Provedor de dados: | Revista Brasileira de Engenharia Agrícola e Ambiental
País: | Brazil
Título: | Nitrate: ammonium nutrition alleviates detrimental effects of salinity by enhancing photosystem II efficiency in sorghum plants
Autores: | Miranda,Rafael de S.; Mesquita,Rosilene O.; Freitas,Natanael S.; Prisco,José T.; Gomes-Filho,Enéas.
Data: | 2014-01-01
Ano: | 2014
Palavras-chave: | Salt stress; Sorghum bicolor; Nitrogen nutrition.
Resumo: | ABSTRACT This study was carried out to evaluate if replacement of nitrate (NO3-) by ammonium (NH4+) in the growth medium prevents the damage in the photosystem II (PSII) efficiency and degradation of photosynthetic pigments caused by saline stress in sorghum plants. Sorghum bicolor plants were cultivated in nutrient solutions containing different NO3-:NH4+ ratios (100:0, 75:25, 50:50, 25:75 and 0:100) at a final concentration of 5.0 mM. Salinity was imposed by adding NaCl at 75 mM in the growth medium; and the analysis were performed after ten days of salt stress. The most striking effects of nitrogen regime were observed in plants supplied with equal amounts of NO3-: NH4+ (50:50). Under salt stress, 50:50-grown plants displayed an increase in the photosystem II maximum efficiency (Fv/Fm), which was associated with a lower non-photochemical quenching (NPQ). The superior performance of salt-stressed plants grown in 50:50 ratio was indicated by a higher effective quantum yield of PSII (ΦPSII) and electron transport rate (ETR), as well as increased chlorophyll b and anthocyanins. In conclusion, nitrogen nutrition with same amounts of nitrate and ammonium avoids the degradation of photosynthetic pigments and allows higher PSII efficiency in salt-stressed sorghum plants.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662014001300008
Editor: | Departamento de Engenharia Agrícola  - UFCG
Relação: | 10.1590/1807-1929/agriambi.v18nsupps8-s12
Formato: | text/html
Fonte: | Revista Brasileira de Engenharia Agrícola e Ambiental  v.18 suppl.0 2014
Fonte: | info:eu-repo/semantics/openAccess