Submitted to: Horticultural Reviews
Publication Type: Review article
Publication Acceptance Date: 7/16/2013
Publication Date: 5/9/2014
Citation: Glenn, D.M., Kim, S. 2014. Response of perennial specialty crops to climate change. Horticultural Reviews. p. 45. Interpretive Summary:
Technical Abstract: Perennial specialty crop production is sensitive to temperature, water availability, solar radiation, air pollution, and carbon dioxide. Elevated atmospheric cabon dioxide generally increases growth rate and yield, resulting in a higher accumulation of biomass, and fruit production and quality in fruit trees. The value of perennial specialty crops is derived from not only the tonnage but also the quality of the harvested product such as the size of a peach, the red blush on an apple, and the bouquet of a red wine produced from a particular vineyard. In contrast to annual agronomic crop production, perennial crop production is not easily moved as the climatic nature of a region declines due to many socio-economic factors including: long re-establishment periods, nearness to processing plants, availability of labor, and accessible markets. Eight specialty crops were selected as representative food crops (apple [Malus pumila], blueberry [Vaccinium spp.], cherry [Prunus avium], citrus [Citrus spp.], grape [Vitis spp.], peach [Prunus persica], pear [Pyrus communis], and raspberry [Rubus spp.]). Red maple [Acer rubrum] was selected as a representative perennial nursery and ornamental crop. Critical temperature and photosynthetically active radiation (PAR) thresholds for key phenological stages were identified in the scientific literature (Tables 1a, b, c and 2). Conservative thresholds were selected from the literature for this database for use by crop/climate modelers and policy makers in assessing future climate change impacts. The response of these crops to elevated atmospheric [carbon dioxide] roughly doubling from a base level near 350~400 ppm is evaluated from the scientific literature. Perennial specialty crops exhibit physiological and growth responses that are similar to trees in forests and other unmanaged ecosystems. The carbon dioxide fertilization effect may be amplified and sustained longer for perennial specialty crops if 1) other resources (e.g., nutrients and water availability) are amply supplied, and 2) proper management options (e.g., spacing, pruning, thinning) are practiced to facilitate the prolonged carbon dioxide effects. This will likely require maintaining intensive cropping systems. In addition, the positive carbon dioxide effect may be negated by the detrimental effects of extreme temperatures on phenology, carbon sinks, and reproductive physiology. There is a lack of information on the yield and quality responses of perennial specialty crops to elevated carbon dioxide and the interaction with warming temperatures. Thus, innovative research for low-input cropping systems that integrates our current knowledge to capitalize on the benefits of elevated carbon dioxide while minimizing the input and costs, and temperature stresses is highly needed.