Evaluation of diverse chickpea lines for anoxia tolerance and investigation of associated physiological traits

TY - ABST

T1 - Evaluation of diverse chickpea lines for anoxia tolerance and investigation of associated physiological traits

AU - Kotula, Lukasz

AU - Nielsen, Sune Ringsing

AU - Pedersen, Ole

AU - Colmer, Timothy David

PY - 2019/6/2

Y1 - 2019/6/2

N2 - Waterlogged soils typically become anoxic within a few days of soil flooding resulting in stress to many crops. Chickpea is one of the least waterlogging tolerant grain legumes and flooding at seedling stage can even result in complete submergence of the entire plant. We screened a diverse set of chickpea lines (90 lines in total) for anoxia tolerance. We also investigated responses to hypoxia of respiration rates and the apparent critical O2 pressure for respiration (COPR) of roots in eight contrasting chickpea lines. Anoxia tolerance was assessed by ability for root extension (i.e. root tip survival) upon 96 h reaeration following 48 h anoxia, of the main axis of the seedling root. Post-anoxic recovery ranged from 0% (cessation of growth of all roots) to approximately 80% survival of root tips. Root respiration rates were measured for excised 25 mm long root segments (10 mm below youngest lateral) in a rapidly-stirred cuvette with pO2 in the incubation medium monitored over time with an O2 sensor. Apparent COPR was established using segmental linear regression of the O2 response curve of respiration rate vs. external pO2, for each chickpea line. There were no significant correlations between anoxia tolerance and respiration (ranged between 1.3 – 1.8 nmol O2 g-1 FW s-1) or apparent COPR (ranged between 1.6 – 3.9 kPa) across the eight contrasting chickpea lines. Further investigation of a larger number of lines is needed to fully assess the diversity in respiration and apparent COPR, and we will also evaluate a set of contrasting chickpea lines for rates of ethanol production and other traits in our future experiments.

AB - Waterlogged soils typically become anoxic within a few days of soil flooding resulting in stress to many crops. Chickpea is one of the least waterlogging tolerant grain legumes and flooding at seedling stage can even result in complete submergence of the entire plant. We screened a diverse set of chickpea lines (90 lines in total) for anoxia tolerance. We also investigated responses to hypoxia of respiration rates and the apparent critical O2 pressure for respiration (COPR) of roots in eight contrasting chickpea lines. Anoxia tolerance was assessed by ability for root extension (i.e. root tip survival) upon 96 h reaeration following 48 h anoxia, of the main axis of the seedling root. Post-anoxic recovery ranged from 0% (cessation of growth of all roots) to approximately 80% survival of root tips. Root respiration rates were measured for excised 25 mm long root segments (10 mm below youngest lateral) in a rapidly-stirred cuvette with pO2 in the incubation medium monitored over time with an O2 sensor. Apparent COPR was established using segmental linear regression of the O2 response curve of respiration rate vs. external pO2, for each chickpea line. There were no significant correlations between anoxia tolerance and respiration (ranged between 1.3 – 1.8 nmol O2 g-1 FW s-1) or apparent COPR (ranged between 1.6 – 3.9 kPa) across the eight contrasting chickpea lines. Further investigation of a larger number of lines is needed to fully assess the diversity in respiration and apparent COPR, and we will also evaluate a set of contrasting chickpea lines for rates of ethanol production and other traits in our future experiments.

M3 - Conference abstract for conference

T2 - 2019 ISPA Conference

Y2 - 2 June 2019 through 5 June 2019

ER -