|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: Agricultural Water Management
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/1/2016
Publication Date: 12/15/2016
Citation: Ruttanaprasert, R., Jogloy, S., Vorasoot, N., Kesmala, T., Kanwar, R.S., Holbrook Jr, C.C., Patanothai, A. 2016. Effect of water stress on total biomass, tuber yield, harvest index and water use efficiency in Jerusalem artichoke. Agricultural Water Management. 166:130-138.
Interpretive Summary: Jerusalem artichoke is an under-utilized crop native to North America. Inulin is a form of carbohydrate stored in Jerusalem artichoke tubers instead of starch which is stored in most tuber and root crops. Inulin is beneficial to human health as it is not digested in the digestive system and, therefore, functions as a soluble fiber. Jerusalem artichoke is the best candidate for inulin production in the tropics, where artichoke and chicory (the other inulin containing crops) cannot be grown commercially. The objectives of this study were to determine the effects of drought on tuber yield, total biomass, harvest index and water use efficiency. Five jerusalem artichoke varieties were studied under three water regimes. Drought reduced tuber dry weight, total biomass, harvest index and water use efficience. The variety JA 5 had relative high yield and water use efficiency across water regimes and could be used as a parent in breeding for drought tolerance.
Technical Abstract: The objectives of this study were to determine the effect of drought on tuber yield, total biomass, harvest index, water use efficiency of tuber yield (WUEt) and water use efficiency of biomass (WUEb), and to evaluate the differential responses of Jerusalem artichoke (JA) varieties under drought stress. The 3x5 factorial combinations of three water regimes (Field capacity (FC), 50% available soil water (50%AW) and 25%AW), and five JA varieties (JA 60, JA 125, JA 5, JA 89 and HEL 65) were arranged in a pot experiment in a randomized complete block design with four replications for two years. Data were recorded for tuber dry weight, total biomass, harvest index, WUEt and WUEb at harvest. Drought reduced tuber dry weight, total biomass, harvest index, WUEt and WUEb, and reductions were more severe under the severe drought of 25%AW. Varieties were significantly different for all traits under drought and well-watered conditions. The JA varieties were classified into threee groups. The first category was comprised of the JA 5 variety with high tuber yield potential and low drought tolerance, the second category consisted of JA 60 and JA 125 varieties with low tuber yield potential and high drought tolerance, and the third group included JA89 and HEL 65 varieties with low yield potential and low drought tolerance. The reductions in tuber dry weight, total biomass, and harvest index were the most important factors affecting tuber yield, total biomass, and harvest index under drought stress conditions. Therefore, the results of this study recommend that the selection of JA genotypes with low reduction in yield under drought stress could be a criterion in drought resistance breeding programs for development of JA varieties with high tuber yield under drought stress. JA with drought tolerance in this study means high tuber yield under drought conditions. JA 5 had high yield and WUEt across water regimes and could be used as parental source for drought tolerance breeding programs in further research.