TY - JOUR
T1 - Elevated CO 2 affects plant responses to variation in boron availability
AU - Mishra, Sasmita
AU - Heckathorn, Scott A.
AU - Frantz, Jonathan M.
PY - 2012/1
Y1 - 2012/1
N2 - Aim: Effects of elevated CO 2 on N relations are well studied, but effects on other nutrients, especially micronutrients, are not. We investigated effects of elevated CO 2 on response to variation in boron (B) availability in three unrelated species: seed geranium (Pelargonium x hortorum), barley (Hordeum vulgare), and water fern (Azolla caroliniana). Methods: Plants were grown at two levels of CO 2 (370, 700 ppm) and low, medium, and high B. Treatment effects were measured on biomass, net photosynthesis (P n) and related variables, tissue nutrient concentrations, and B transporter protein BOR1. Results In geranium, there were interactive effects (P < 0. 05) of B and CO 2 on leaf, stem, and total plant mass, root:shoot ratio, leaf [B], B uptake rate, root [Zn], and P n. Elevated CO 2 stimulated growth at 45 μM B, but decreased it at 450 μM B and did not affect it at 4. 5 μM B. P n was stimulated by elevated CO 2 only at 45 μM B and chlorophyll was enhanced only at 450 μM B. Soluble sugars increased with high CO 2 only at 4. 5 and 45 μM B. High CO 2 decreased leaf [B] and B uptake rate, especially at 450 μM B. Though CO 2 and B individually affected the concentration of several other nutrients, B x CO 2 interactions were evident only for Zn in roots, wherein [Zn] decreased under elevated CO 2. Interactive effects of B and CO 2 on growth were confirmed in (1) barley grown at 0, 30, or 1,000 μM B, wherein growth at high CO 2 was stimulated more at 30 μM B, and (2) Azolla grown at 0, 10, and 1,000 μM B, wherein growth at high CO 2 was stimulated at 0 and 10 μM B. Conclusion: Thus, low and high B both may limit growth stimulation under elevated vs. current [CO 2], and B deficiency and toxicity, already common, may increase in the future.
AB - Aim: Effects of elevated CO 2 on N relations are well studied, but effects on other nutrients, especially micronutrients, are not. We investigated effects of elevated CO 2 on response to variation in boron (B) availability in three unrelated species: seed geranium (Pelargonium x hortorum), barley (Hordeum vulgare), and water fern (Azolla caroliniana). Methods: Plants were grown at two levels of CO 2 (370, 700 ppm) and low, medium, and high B. Treatment effects were measured on biomass, net photosynthesis (P n) and related variables, tissue nutrient concentrations, and B transporter protein BOR1. Results In geranium, there were interactive effects (P < 0. 05) of B and CO 2 on leaf, stem, and total plant mass, root:shoot ratio, leaf [B], B uptake rate, root [Zn], and P n. Elevated CO 2 stimulated growth at 45 μM B, but decreased it at 450 μM B and did not affect it at 4. 5 μM B. P n was stimulated by elevated CO 2 only at 45 μM B and chlorophyll was enhanced only at 450 μM B. Soluble sugars increased with high CO 2 only at 4. 5 and 45 μM B. High CO 2 decreased leaf [B] and B uptake rate, especially at 450 μM B. Though CO 2 and B individually affected the concentration of several other nutrients, B x CO 2 interactions were evident only for Zn in roots, wherein [Zn] decreased under elevated CO 2. Interactive effects of B and CO 2 on growth were confirmed in (1) barley grown at 0, 30, or 1,000 μM B, wherein growth at high CO 2 was stimulated more at 30 μM B, and (2) Azolla grown at 0, 10, and 1,000 μM B, wherein growth at high CO 2 was stimulated at 0 and 10 μM B. Conclusion: Thus, low and high B both may limit growth stimulation under elevated vs. current [CO 2], and B deficiency and toxicity, already common, may increase in the future.
KW - Azolla
KW - Barley
KW - Boron stress
KW - Boron transporter protein (BOR1)
KW - Geranium
KW - Nutrients
KW - Photosynthesis
UR - http://www.scopus.com/inward/record.url?scp=83555179231&partnerID=8YFLogxK
U2 - 10.1007/s11104-011-0888-6
DO - 10.1007/s11104-011-0888-6
M3 - Article
AN - SCOPUS:83555179231
SN - 0032-079X
VL - 350
SP - 117
EP - 130
JO - Plant and Soil
JF - Plant and Soil
IS - 1-2
ER -