Corn salad (Valerianella locusta (L.) Laterr.) growth in a water-saving floating system as affected by iron and sulfate availability.
BACKGROUND
Unbalanced nutrient availability causes disequilibrated plant growth, which can result in a worsening of harvested product quality, such as high nitrate content in edible tissues. To cope with this problem, improved knowledge of the mechanisms involved in nutrient acquisition and regulation is necessary. For this purpose the responses of acquisition mechanisms of N, Fe and S were studied as a function of Fe and S availability using two corn salad cultivars grown hydroponically, considering also aspects related to N metabolism.


RESULTS
The results showed that an increase in Fe or S availability enhanced nitrate uptake and assimilation, which in turn increased biomass production of leaves with lower nitrate content. In particular, high S availability exerted a positive effect (gene expression and functionality) both on the uptake and metabolism of N and on Fe acquisition mechanisms.


CONCLUSIONS
The data presented here show close interactions between N, S and Fe, highlighting that relevant improvements in yield and quality from soilless culture might also be obtained through appropriate adjustments of nutrient availability. In this respect, concerning the role of S in the acquisition mechanisms of N and Fe and in N metabolism, its level of availability should be taken into high consideration for equilibrated plant growth.
Dipartimento di Scienze Agrarie e Ambientali, University of Udine, I-33100 Udine, Italy.
Francesco
F
Iacuzzo
Stefano
S
Gottardi
Nicola
N
Tomasi
Elisa
E
Savoia
Rita
R
Tommasi
Giovanni
G
Cortella
Roberto
R
Terzano
Roberto
R
Pinton
Luisa
L
Dalla Costa
Stefano
S
Cesco
D000383:Agriculture / Q000379:methods*; D001692:Biological Transport; D018533:Biomass; D005308:Fertilizers; D015870:Gene Expression; D007501:Iron / Q000378:metabolism*; D009566:Nitrates / Q000378:metabolism*; D009584:Nitrogen / Q000378:metabolism*; D018515:Plant Leaves / Q000254:growth & development / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism; D013431:Sulfates / Q000378:metabolism*; D013455:Sulfur / Q000378:metabolism*; D032406:Valerianella / Q000254:growth & development* / Q000378:metabolism; D014867:Water
D005308:Fertilizers; D009566:Nitrates; D013431:Sulfates; D014867:Water; D013455:Sulfur; D007501:Iron; D009584:Nitrogen