Influence of ammonium, nitrate, and chloride on solution pH and ion uptake by ageratum and salvia in hydroponic culture

Abstract

The influence of nitrogen (N) forms and chloride (Cl) on solution pH and ion uptake in the hydroponic culture of Ageratum houstonianum [ammonium (NH 4 + )-tolerant] and Salvia splendens (NH 4 + -sensitive) for a period of 216 hours was investigated. The pH of the hydroponic solution (initially 6.50) containing either NH 4 + or NH 4 + +nitrate (NO 3 -) was drastically lowered (3.08), whereas that of the same solution containing NO 3 -was raised (7.74). Solution pH changed more by ageratum than by salvia. The solution Cl -concentration did not influence pH significantly. However, addition of Cl -in the solution lowered transpiration rate in both NH 4 + and NO 3 -treatments. Total N uptake was the greatest in the NH 4 + + NO 3 -treatment and the lowest in the NO 3 -treatment. In the NH 4 + + NO 3 -treatment, NO 3 -uptake was suppressed by NH 4 + (to about 50%), while NH 4 + uptake was not affected by NO 3 -. The rate of Cl uptake was the lowest in the NH 4 + treatment, but was similar in the NH 4 + +NCy and NCy treatments. Uptake of potassium (K + ), dihydrogen 1344 JEONGANDLEE phosphate (H 2 PO 4 -), sulfate (SO 4 -2), manganese (Mn +2 ), and zinc (Zn +2 ) was significantly enhanced in the NH 4 + treatment. The uptake rate of calcium (Ca +2 ) and magnesium (Mg +2 ) was the highest in the NO 3 -treatment. Absorption of copper (Cu +2 ) and boron (B) was not affected by N source. Ion uptake was more stable in the solution containing both NH 4 + and NO 3 -than in the solution containing either NH 4 + or NO 3 -. The uptake rate of total N, NH 4 + , NO 3 -, Mn +2 , Cu +2 , and Zn +2 was higher, whereas that of Cl -and molybdenum (Mo) was lower in ageratum than in salvia. Amounts of total anion (TA) and total cation (TC) absorbed, the sum of TC and TA, and the difference between TC and TA (TC-TA) were affected by N source, Cl -level, and their interactions. The NO 3 treatment, as compared to the NH 4 + or the NH 4 + + NO 3 -treatment, reduced total cation and anion uptake while increasing TC-TA, especially in the absence of Cl". Plant tissue ion contents were also affected by N source and Cl" level.

Temperature determines size and direction of effects of elevated CO2 and nitrogen form on yield quantity and quality of Chinese cabbage

“…). Some previous studies have demonstrated an increase in zinc in plants supplied with ammonium instead of nitrate (Jeong & Lee ), but the present study is the first to show (as far as we are aware) that ammonium nitrate has the potential to override the effect of e[CO 2 ] on zinc accumulation. In accordance with these findings, the meta‐analysis of Myers et al .…”

“…A more likely explanation seems to be the accumulation of these nutrients at the root surface, which increases with pH and hinders nutrient uptake (Blair et al 1971). Some previous studies have demonstrated an increase in zinc in plants supplied with ammonium instead of nitrate (Jeong & Lee 1996), but the present study is the first to show (as far as we are aware) that ammonium nitrate has the potential to override the effect of e[CO 2 ] on zinc accumulation. In accordance with these findings, the meta-analysis of Myers et al (2014) revealed that the decrease in zinc by e[CO 2 ] was less pronounced in rice than in wheat, pea and soybean.…”

A Simple Method for Quantitative Estimation of Rhizosphere pH along Root Axes through Visualization

“…In the presence of either ammonium or ammonium nitrate, the rhizosphere is normally acidified ( Gijsman, 1990;Jeong and Lee, 1996), but our results demonstrated that this acidification was caused by the light given to the shoot. This might be due to the greater absorption of the cationic form of nitrogen in light than in the dark (Qurry et al, 1996;Macduff et al, 1997).…”

“…It is well known that the form of nitrogen supplied (ammonium as cation or nitrate as anion) to the roots greatly influences the cation-anion uptake ratio, because nearly 70% of cations or anions taken up by the plants are ammonium or nitrate (van Beusichem et al, 1988). In fact, many studies have shown that the supply of nitrogen as ammonia acidifies, whereas the supply of nitrate alkalizes the rhizosphere in many crop species (Marschner and Romheld, 1983;Gijsman, 1990;Jeong and Lee, 1996). Legumes are exceptions, which acidify the rhizosphere even after the supply of nitrate (Marschner and Romheld, 1983) .…”

Mobilization of Labelled Organic Sulfur in Rhizosphere of Rape and Barley and in Non-Rhizosphere Soil

“…However, significant correlation coefficient between arylsulfatase activity and 35 S uptake by roots (Fig. In consequence, the uptake of these anions from the non-rhizosphere of barley would be, mostly, by a mass flow mechanism, [28] and 35 S-SHW may present a readily available source of S. In view of these results, rape root exudates would have a real influence on the microbial communities even outwards the rhizosphere zone. Due to the alkaline pH of the soil used (pH : 8), the adsorption of sulfates would be negligible.…”