|RUTTANAPRASERT, R - Khon Kaen University|
|JOGLOY, S - Khon Kaen University|
|VORASOOT, N - Khon Kaen University|
|KESMALA, T - Khon Kaen University|
|KANWAR, R - Khon Kaen University|
|Holbrook, Carl - Corley|
|PATANOTHAI, A - Khon Kaen University|
Submitted to: Biomass and Bioenergy
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/15/2015
Publication Date: 11/15/2015
Citation: Ruttanaprasert, R., Jogloy, S., Vorasoot, N., Kesmala, T., Kanwar, R.S., Holbrook Jr, C.C., Patanothai, A. 2015. Root response of Jerusalem artichoke genotypes to different water regimes. Biomass and Bioenergy. 81:369-377.
Interpretive Summary: Drought tolerance may be enhanced by exploiting drought avoidance mechanisms such as the ability of roots to extract water from the soil. The objective of this study was to determine the effect of drought on selected root growth parameters of five Jerusalem artichoke varieties. Drought stress reduced shoot dry weight, root diameter, root length, root surface area, and root volume in all varieties. However, variations in responses to drought for root traits were observed among the varieties. Three varieties with superior root growth parameters under drought stress were identified. Breeding for maintaining yield under water-limited conditions by the adaptation of root parameters may facilitate the development of improved Jerusalem artichoke varieties in specific water limited-environments.
Technical Abstract: The objective of this study was to determine effects of drought on selected root growth parameters and develop relationships between root parameters and tuber yield for selected Jerusalem artichoke (JA) genotypes. Three water regimes (Field capacity, 50% available water (AW) and 25% AW) and five JA varieties (JA 60, JA 125, JA 5, JA 89 and HEL 65) were planted with factorial treatments in a randomized complete block design with four replications. Data on root dry weight (RDW) and root:shoot ratios (RSR) were measured manually. Root diameter (RD), root length (RL), root surface area (RSA) and root volume (RV) were collected at harvest. Drought tolerance indices (DTI) were calculated for all root parameters. Drought reduced all root parameters and DTI but increased RSR in JA 60, JA 125, JA 5, and HEL 65. JA 125 had high values for all root traits and DTI of these traits under drought stress. JA 60 had high DTI of RDW, RD and RSR under mild and severe water stress. JA 5 had high DTI of RDW, RD, RL, RSR and RV under drought conditions. JA 89 and HEL 65 performed well for RDW, RD, RL and low DTI of all root characteristics. DTI for root parameters were positively correlated with tuber dry weight under mild and severe water stress. The JA 5, JA 60 and JA 125 varieties showed high DTI for some root traits, indicating that better root parameters contributed to higher tuber yield under drought stress.