Abstract
A growth chamber experiment was conducted to investigate the influence of NH +4 /NO −3 ratio and elevated CO2 concentration on the pH in nutrient solution, growth and root vigor system of tomato seedling roots, which attempts to understand whether the elevated CO2 concentration can alleviate the harmful effects of higher NH +4 -N concentration in nutrient solutions on the tomato root system. Tomato (Lycopersicon esculentum Mill. var. Hezuo 906) was grown in pots with nutrient solutions varying in NH +4 /NO −3 ratio (0:1, 1:3, 1:1, 3:1 and 1:0) and the growth chambers were supplied with ambient (360 μL·L−1) or elevated CO2 concentration (720 μL·L−1). The results showed that the pH changed with the growth process and CO2 concentration increased. At both CO2 levels, pH increased when 100% NO −3 -N was supplied and decreased in other treatments. The pH decrease in the nutrient solution was directly correlated to the NH +4 -N proportion. The pH value was more reduced in 100% NH +4 -N nutrient solution than increased in the 100% NO −3 -N nutrient solution. CO2 enrichment increased the dry weight of shoots and roots, root vigor system, total absorbing area and active absorbing area of tomato seedlings. All the measurement indexes above were increased in the elevated CO2 concentration treatment with the NO −3 proportion increase in the nutrient solutions. Thus, under the elevated CO2 concentration, the dry weights of shoots and roots, root vigor system, total root absorbing area and active absorbing area were found to be inversely correlated to NH +4 /NO −3 ratio, leading to about 65.8%, 78.0%, 18.9%, 12.9% and 18.9% increase, respectively, compared with that under the ambient CO2 concentration. Our results indicated that tomato seedling roots may benefit mostly from CO2 enrichment when 100% NO −3 -N nutrient solutions was supplied, but the CO2 concentration elevation did not alleviate the harmful effects when 100% NH +4 -N was supplied.
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References
Brouwer R (1983). Functional equilibrium: sense or nonsense? Netherlands. J Agric Sci, 31: 335–348
Cramer MD, Lewis O A M (1993). The influence of NO −3 and NH +4 nutrition on the carbon and nitrogen partitioning characteristics of wheat (Triticum aestivum L.) and maize (Zea mays L.) plants. Plant Soil, 154: 289–300
Faculty of Plant Physiology, Department of Biology, East China Normal University (1988). Experimental Guide of Plant Physiology. Beijing: Higher Education Press (in Chinese)
Findenegg G R (1987). A comparative study of ammonium toxicity at different constant pH of the nutrient solution. Plant Soil, 103: 239–244
Gao J F (2000). Experimental Techniques of Plant Physiology. Xi’an: World Books Publishing Company (in Chinese)
Li J, Zhou J M, Duan Z Q, Du C W, Wang H Y (2005a). Effects of the interactions of carbon dioxide and nutrients on tomato seedlings. Acta Bot Boreali-occident Sin, 25(10): 2112–2117 (in Chinese)
Li J, Zhou JM, Duan Z Q, Du C W, Wang H Y (2005b). The effect of the interactions between nutrient supplying intensity and carbon dioxide enrichment on the growth and some physiological indexes of tomato. Acta Agriculturae Boreali-occidentalis Sinica, 14(4): 10–13 (in Chinese)
McConnaughay K D M, Coleman J S (1999). Biomass allocation in plants: ontogeny or optimality? A test along three resource gradients. Ecology, 80: 2581–2593
Mehrer I, Mohr H (1989). Ammonium toxicity: Description of the syndrome in Sinapis alba and the search for its causation. Physiol Plant, 77: 545–554
Olsthoorn A F M, Keltjens W G, Van Baren B, Hopman M C G (1991). Influence of ammonium on fine root development and rhizosphere pH of Douglas-fir seedling in sand. Plant and Soil, 133: 75–81
Reynolds J F, Thornley J H M (1982). A shoot: root partitioning model. Annals of Botany, 49: 585–597
Troelstra S R, Wagenaar R, Smant W (1995). Nitrogen utilization by plant species from acid heathland soils: I. Comparison between nitrate and ammonium nutrition at constant low pH. J Exp Bot, 46: 1103–1112
Wei M, Xing Y X, Ma H, Wang X F, Li B (2000). Effects of CO2 enrichment in raising vigorous seedlings of fruited vegetable. Journal of Shandong Agricultural University (Natural Science), 31(2): 196–200 (in Chinese)
Wilson J B (1988). A review of evidence on the control of shoot: root ratio, in relation to models. Annals of Botany, 61: 433–449
Xu D Q (1994). Responses of photosynthesis and related processes to long-term high CO2 concentration. Plant Physiology Communications, 30(2): 81–87 (in Chinese)
Yang H J, Yang L X, Liu H J, Huang J H, Dong G C, Zhu J G, Wang Y L (2006). Effect of free-air CO2 enrichment on root activity of Japonica rice (Oryza sativa L.) cultivar Wuxiangjing 14. Acta Agronomica Sinica, 32(1): 118–124 (in Chinese)
Zhang F C, Kang S Z, Ma Q L (1999). The effects of the atmospheric CO2 concentration increase on physiological characters and growth of cotton. Journal of Basic Science and Engineering, 7(3): 267–272 (in Chinese)
Zhang F S (1998). Environmental Stress and Rhizosphere Nutrition. Beijing: China Agricultural Press (in Chinese)
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Translated from Plant Nutrition and Fertilizer Science, 2007, 13(5): 865–870 [译自: 植物营养与肥料学报]
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Li, J., Zhou, J. Effect of interactions between carbon dioxide enrichment and NH +4 /NO −3 ratio on pH of culturing nutrient solution, growth and vigor of tomato root system. Front. Agric. China 2, 296–300 (2008). https://doi.org/10.1007/s11703-008-0046-y
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DOI: https://doi.org/10.1007/s11703-008-0046-y