TY - JOUR
T1 - Can nitrate-based fertilization be recommended for the cultivation of ammonium-preferring species in a salty ecosystem? The case for Spartina alterniflora
AU - Hessini, Kamel
AU - Jeddi, Kaouthar
AU - Siddique, Kadambot H.M.
AU - Moran, Jose Fernando
PY - 2021/7
Y1 - 2021/7
N2 - Nitrogen (N) is an indispensable mineral nutrient for plant growth and development. Proper nitrogen (N) management, in terms of quality and availability, can increase plant productivity and reduce soil N losses. This study investigated the impact of N availability (form and dose) on the growth, water relations, and nitrogen status and assimilation of smooth cordgrass (Spartina alterniflora) in the presence of 200 mM NaCl. At the optimal N concentration, ammonium (NH4+) application improved biomass production and total leaf area more than nitrate (NO3–) application—the leaves-free NH4+ contents remained very low and did not reach the plant toxicity threshold, while those of NO3− were low, regardless of N form. Compared to NO3−, the use of NH4+ as the sole N source increased water economy. However, at low N concentration, S. alterniflora was sensitive to NH4+ deficiency. Media containing 0.25 or 0.5 mM N as NH4+ inhibited plant growth, causing general chlorosis and cell death, particularly on the lower leaves. In contrast, the response of S. alterniflora to NO3− dose did not significantly differ, indicating their preference for NH4+. The lower glutamine synthetase activity in NH4+-fed plants also suggests NH4+ tolerance. Our findings question the use of NO3−-based fertilizers for species that prefer NH4+ as an N source in salt-affected soil.
AB - Nitrogen (N) is an indispensable mineral nutrient for plant growth and development. Proper nitrogen (N) management, in terms of quality and availability, can increase plant productivity and reduce soil N losses. This study investigated the impact of N availability (form and dose) on the growth, water relations, and nitrogen status and assimilation of smooth cordgrass (Spartina alterniflora) in the presence of 200 mM NaCl. At the optimal N concentration, ammonium (NH4+) application improved biomass production and total leaf area more than nitrate (NO3–) application—the leaves-free NH4+ contents remained very low and did not reach the plant toxicity threshold, while those of NO3− were low, regardless of N form. Compared to NO3−, the use of NH4+ as the sole N source increased water economy. However, at low N concentration, S. alterniflora was sensitive to NH4+ deficiency. Media containing 0.25 or 0.5 mM N as NH4+ inhibited plant growth, causing general chlorosis and cell death, particularly on the lower leaves. In contrast, the response of S. alterniflora to NO3− dose did not significantly differ, indicating their preference for NH4+. The lower glutamine synthetase activity in NH4+-fed plants also suggests NH4+ tolerance. Our findings question the use of NO3−-based fertilizers for species that prefer NH4+ as an N source in salt-affected soil.
KW - Ammonium
KW - Nitrate
KW - Nitrogen deficiency
KW - Salinity
KW - Water economy
UR - http://www.scopus.com/inward/record.url?scp=85109354340&partnerID=8YFLogxK
U2 - 10.1007/s12517-021-07662-7
DO - 10.1007/s12517-021-07662-7
M3 - Article
AN - SCOPUS:85109354340
SN - 1866-7511
VL - 14
JO - Arabian Journal of Geosciences
JF - Arabian Journal of Geosciences
IS - 13
M1 - 1259
ER -