Js. Kuehny et B. Morales, EFFECTS OF SALINITY AND ALKALINITY ON PANSY AND IMPATIENS IN 3 DIFFERENT GROWING MEDIA, Journal of plant nutrition, 21(5), 1998, pp. 1011-1023
The quality of irrigation water used for greenhouse crop production ca
n strongly influence plant growth. However, the effect on plant growth
is probably a combination of water quality and the type of growing me
dia used. To determine the effect of saline and alkaline irrigation wa
ter on plant growth and nutrition, pansy and impatiens were grown in p
eat, peat:pine bark, and pine bark media under standard greenhouse con
ditions. Salinity treatments of 0, 100, and 400 mg L-1 NaCl:CaCl2 and
alkalinity treatments of 0, 100, 200, 300, and 400 mg L-1 NaHCO3 were
applied at every irrigation. Salinity levels at 100 mg L-1 and greater
caused necrosis of leaf edges, upward curling of leaves, and reduced
newer number for pansy. Treatment symptoms for impatiens were reduced
growth, general chlorosis, and reduced flower number. These treatment
symptoms increased in severity for plants grown in pine bark. Alkalini
ty levels at 200 mg L-1 and greater caused decreased newer number, nec
rosis of leaf edges, and downward cupping of leaves of pansy. Treatmen
ts symptoms of impatiens were general chlorosis, water-soaked appearan
ce of leaves and leaf abscission. Elemental concentrations of sodium (
Na+), chloride (Cl-), calcium (Ca++), magnesium (Mg++), and potassium
(K+) varied in media solution and tissue with symptom and treatment.