Location: Sustainable Perennial Crops LaboratoryTitle: Impact of drought on morphological, physiological and nutrient use efficiency of elite cacao genotypes from Bahia-Brazil, Tarapoto-Peru and Puerto Rico-USA
|ALMEIDA, A - University Of Santa Cruz - Brazil|
|AHNER, D - University Of Santa Cruz - Brazil|
|PIRES, J - Cocoa Research Center - Brazil|
|AREVALO-GARDINI - Tropical Crop Institute (ICT)|
|HE, Z - University Of Florida|
Submitted to: Symposium Proceedings
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/3/2017
Publication Date: 6/20/2018
Citation: Baligar, V.C., Almeida, A.A., Ahner, D., Pires, J.L., Arevalo-Gardini, Goenaga, R.J., He, Z., Elson, M.K. 2018. Impact of drought on morphological, physiological and nutrient use efficiency of elite cacao genotypes from Bahia-Brazil, Tarapoto-Peru and Puerto Rico-USA. Symposium Proceedings. 87:1-11.
Interpretive Summary: Worldwide, drought is considered one of the most limiting factors for cacao growth, development, nutrition and production. Very little is known about cacao's ability to adapt to short or long duration drought. There is an urgent need to identify cacao genotypes with drought tolerance and most of the current cacao germplasm maintained in various cacao collections has not been screened for either short or prolonged drought tolerance. Morphological and nutrient uptake changes appear to be good traits for selection of cacao in its early stages for tolerance to drought. In this paper, we report the impact of drought on morphological, physiological and nutrient use efficiency of elite cacao genotypes from Bahia-Brazil, Tarapoto, Peru and Mayaguez, Puerto Rico. Our results indicate that greenhouse and growth chamber methods adapted for this evaluation are effective in identifying genotypes with various degrees of drought tolerance. Tolerant genotypes can be useful in crop improvement programs to breed superior cultivars for drought stressed ecosystems thereby enhancing the cacao sustainability in drought prone cacao growing regions of the world.
Technical Abstract: Worldwide, drought is considered one of the most limiting abiotic stress factors for cacao growth, development and production. A series of greenhouse and growth chamber experiments were undertaken to assess drought effects on early cacao morphological and physiological traits and nutrient use efficiency of elite cacao genotypes of Brazil, Peru and Puerto Rico. Cacao genotypes showed varying degrees of intra-specific variations for growth (shoot and root biomass, leaf area, specific leaf area, stem height and diameter, root length, relative growth rate), physiology (photosynthesis, chl a/b, net assimilation rate, water use efficiency) and macro nutrient use efficiency under drought. Understanding of growth, morphology, physiology and nutrient use efficiency plant traits influenced by drought will facilitate identification of cacao genotypes tolerant to drought. Such drought tolerant genotypes could be useful in crop improvement programs to breed superior cultivars for drought stressed ecosystem.