The Effect of Root Temperature and Nitrate/Ammonium Ratio on Strawberry Plants. II. Nitrogen Uptake, Mineral Ions, and Carboxylate Concentrations¹

Abstract

Strawberry plants (Fragaria ananasa Duch.) have shallow roots and are grown in the field during both hot and cold seasons. The possibility of irrigating and fertilizing the plants daily, through the trickle system, led to the question of what is the best nitrogen form and N03 /NHt ratios to be supplied to this crop during the growing season. The effect of four root temperatures (10, 17, 25 and 32 oq and five N03 /NHt mole ratios (0/7, 2/5, 3.5/3.5, 5/2, 7 /0) at constant total N in the solution was studied. To keep constant pH, total nutrient solution and root temperature, continuous flow techniques were used. The solution was flushed through 1-L pots at the rate of 1 L h-1 • When both N forms were present, the rate oftotal N uptake was higher than when NHt or NO) alone was present. The maximum uptake rate was found at 25 oc root temperature. Best conditions for growth were found at 25 oc root temperature when both N forms were present in equal concentration. A preference for NO) uptake was found during flowering and the fruiting period. Ammonium was preferred during the vegetative growth period. Increasing root temperature decreased total cation concentration and especially that of K+, Na+, and Mg 1 +, and increased Ca 1 + in the roots of NO) -fed plants. The Na + was accumulated in the crown and did not move to the leaves and fruits. Increasing root temperature reduced inorganic anion concentration in the roots while increasing it in leaves of NHt fed plants. In the fruits, the ratio of mole of charges of Cal+ to that of H 1 PO.;-was about 1:1 for both N forms.

Root‐zone temperature affects nutrient uptake and growth of snapdragon

“…However, in other studies with tomato, strawberry, or chrysanthemum, Mg uptake did not change as root-zone temperature changed (Ganmore-Neumann and Kafkafi, 1985;Kafkafi, 1990;Selmer-Olsen and Gislerod, 1982).…”

“…A study with white clover showed no changes in NO3--N: NH4+-N uptake ratio as temperatures ranged from 3 to 25"C (Hatch and Macduff, 1991), while in a study with barley, the NO3--N.-NH4+-N uptake ratio varied greatly across root-zone temperatures (Macduff and Hopper, 1986). As root-zone temperatures increased, the NO3--N:NH4+-N uptake ratio either decreased or increased for strawberry and tomato, respectively (Ganmore-Newman and Kafkafi, 1985;Tindall et al, 1990).…”

Combined Irrigation and Fertilization in Arid Zones

“…However, in early experiments conducted at constant N concentrations the solution temperature was not controlled (Clark, 1936;Kirkby and Mengel, 1967;Kafkafi et al, 1971). In a series of studies (Ganmore-Neumann and Kafkafi, 1980aKafkafi, , 1980bKafkafi, , 1983Kafkafi, , 1985, the N0 3 -INH/ ratios, root temperatures, total N and other nutrients, and pH of the nutrient solution were all kept constant by allowing the nutrient solution to flush the container at a rate of I Uh.…”

“…A reduction in sugar concentration was found in N0 3 --and NH/ -fed plant roots at 25 °C, as compared to roots maintained at lO °C. Increasing the NH/ fraction in the nutrient solution caused Downloaded by [New York University] increasing damage to the root system with increasing root temperature, culminating in root death at 32 °C with only NH 4 +in the solution (Ganmore-Neumann and Kafkafi, 1983Kafkafi, , 1985.…”

Evaluation of a newly developed potassium and nitrogen fertilization regime for soil cultivation of <i>Ranunculus asiaticus</i>

“…Nitrogen (N) is the major macronutrient required for optimum development and function of plants (Daliparthy et al, 1994;Marschner, 1995). Nitrogen nutrition and fertigation regime influence a range of processes that might affect flower quality, such as osmoregulation (Smirnof and Stewart, 1985;Salsac et al, 1987;Garcia et al, 1996), tissue water content (Gerendás et al, 1997), leaf water potential (Adler et al, 1996), sugars and organic acid contents (Ganmore-Newmann and Kafkafi, 1985;Chaillou et al, 1991), and uptake of other ions (Bar et al, 1997). Nitrogen affects plant growth and development (Gerendás et al, 1997;Walch-Liu et al, 2000;Gifford et al, 2008); gene expression and metabolism (Scheible et al, 2004;Vidal and Gutierrez, 2008) and a range of processes including photosynthesis (Shelp and Taylor, 1990), root respiration (Matsumoto and Tamura, 1981), water relations and uptake (Ragab, 1980;Guo et al, 2002), and secondary metabolism (Wang and Below, 1996).…”