Carbon and nitrogen metabolism in arbuscular mycorrhizal maize plants under low-temperature stress

TY - JOUR

T1 - Carbon and nitrogen metabolism in arbuscular mycorrhizal maize plants under low-temperature stress

AU - Zhu, Xian-Can

AU - Song, Feng-Bin

AU - Liu, Fulai

AU - Liu, Sheng-Qun

AU - Tian, Chen-Jie

PY - 2015

Y1 - 2015

N2 - Effects of the arbuscular mycorrhizal (AM) fungus Glomus tortuosum on carbon (C) and nitrogen (N) metabolism of Zea mays L. grown under lowerature stress was investigated. Maize plants inoculated or not inoculated with AM fungus were grown in a growth chamber at 25°C for 4 weeks and subsequently subjected to two temperature treatments (15°C, low temperature; 25°C, ambient control) for 2 weeks. Lowerature stress significantly decreased AM colonisation, plant height and biomass. Total N content and activities of glutamate oxaloacetate transaminase and glutamate pyruvate transaminase of AM plants were higher than those of non-AM plants. AM plants had a higher net photosynthetic rate (Pn) than non-AM plants, although low temperature inhibited the Pn. Compared with non-AM plants, AM plants exhibited higher leaf soluble sugars, reducing sugars, root sucrose and fructose contents, and sucrose phosphate synthase and amylase activities at low temperature. Moreover, lowerature stress increased the C:N ratio in the leaves of maize plants, and AM colonisation decreased the root C:N ratio. These results suggested a difference in the C and N metabolism of maize plants at ambient and low temperature regimes. AM symbiosis modulated C metabolic enzymes, thereby inducing an accumulation of soluble sugars, which may have contributed to an increased tolerance to low temperature, and therefore higher Pn in maize plants.

AB - Effects of the arbuscular mycorrhizal (AM) fungus Glomus tortuosum on carbon (C) and nitrogen (N) metabolism of Zea mays L. grown under lowerature stress was investigated. Maize plants inoculated or not inoculated with AM fungus were grown in a growth chamber at 25°C for 4 weeks and subsequently subjected to two temperature treatments (15°C, low temperature; 25°C, ambient control) for 2 weeks. Lowerature stress significantly decreased AM colonisation, plant height and biomass. Total N content and activities of glutamate oxaloacetate transaminase and glutamate pyruvate transaminase of AM plants were higher than those of non-AM plants. AM plants had a higher net photosynthetic rate (Pn) than non-AM plants, although low temperature inhibited the Pn. Compared with non-AM plants, AM plants exhibited higher leaf soluble sugars, reducing sugars, root sucrose and fructose contents, and sucrose phosphate synthase and amylase activities at low temperature. Moreover, lowerature stress increased the C:N ratio in the leaves of maize plants, and AM colonisation decreased the root C:N ratio. These results suggested a difference in the C and N metabolism of maize plants at ambient and low temperature regimes. AM symbiosis modulated C metabolic enzymes, thereby inducing an accumulation of soluble sugars, which may have contributed to an increased tolerance to low temperature, and therefore higher Pn in maize plants.

U2 - 10.1071/CP14159

DO - 10.1071/CP14159

M3 - Journal article

SN - 1836-0947

VL - 66

SP - 62

EP - 70

JO - Crop and Pasture Science

JF - Crop and Pasture Science

IS - 1

ER -