Interaction between soil salinity and nitrogen on growth and gaseous exchanges in guava

Abstract This study evaluated the growth and gas exchanges of guava, cv. ‘Paluma’ cultivated in salinized soil and subjected to different nitrogen (N) doses in a protected environment in the municipality of Campina Grande-PB. The experimental design was randomized blocks, in a 5 x 4 factorial arrangement with three replicates, and the treatments resulted from the combination of five salinity levels in the soil saturation extract - ECse (2.15, 3.15,4.15, 5.15 and 6.15 dS m-1) and four N doses (70, 100, 130 and 160% of the recommended N dose). The dose referring to 100% of N corresponded to 541.1 mg of N dm-3 of soil. At 120 and 180 days after (DAT), plant growth was evaluated based on stem diameter (SD), leaf area (LA) and number of leaves (NL). At 210 DAT, the following variables of leaf gas exchanges were evaluated: stomatal conductance (gs), internal CO2 concentration (Ci), transpiration (E) and CO2 assimilation rate (A). ECse above 2.15 dS m-1 reduced stem diameter, leaf area, number of leaves, stomatal conductance, internal CO2 concentration, transpiration and CO2 assimilation rate, in both evaluation periods. N dose above 70% of the recommendation (378.7 mg N dm-3 of soil) did not mitigate the deleterious effects caused by the salt stress on the growth and gas exchanges of guava plants.

Bibliographic Details

Main Authors:	Bezerra,Idelfonso Leandro, Gheyi,Hans Raj, Nobre,Reginaldo Gomes, Lima,Geovani Soares de, Santos,João Batista dos, Fernandes,Pedro Dantas
Format:	Digital revista
Language:	English
Published:	Instituto de Pesquisas Ambientais em Bacias Hidrográficas 2018
Online Access:	http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1980-993X2018000300312
Tags:	Add Tag No Tags, Be the first to tag this record!