Climate Science Program

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Rajeev Arora


Office: 139 Horticulture Hall

Phone: 515-294-0031



Department: Horticulture

Research Interests: Cold Hardiness and Dormancy (phenology, physiology, genetics, mol. biology)

Brief description of current research:

Dr. Arora’s research focuses on understanding the physiological and molecular mechanisms of seasonal cold hardening and dehardening of over-wintering plants. The research involves identification of key genes and proteins associated with cold hardening (and induction of endodormancy), dehardening (and breaking of endodormancy), and recovery from freeze-thaw injury. His research takes advantage of the presence of natural genetic variation as well as cellular physiology and molecular physiological tools (including genomics, proteomics). Fluctuating temperatures during the mid-winter and spring are of particular concern to the survival of overwintering woody perennials whereby unseasonable warm spells could result in premature dehardening leaving the plants vulnerable to lethal damage by the deep freeze that may soon follow. Therefore, dehardening resistance and rehardening capacity, both of which can be dramatically influenced by the dormancy status of the plant, are very important traits for winter survival. Arora lab is also interested in dissecting the physiology of these traits.

Recent publications:

Kalberer, S.R, N. Leyva-Estrada, S. L. Krebs and R. Arora, 2007: Frost dehardening and rehardening of floral buds of deciduous azaleas depend on genotypic biogeography. Environmental & Experimental Botany, 59, 264-275.

Kalberer, S.R, N. Leyva-Estrada, S. L. Krebs and R. Arora, 2007: Cold hardiness of floral buds of deciduous azaleas: dehardening, rehardening, and endodormancy in late winter. J. Amer. Soc. Hort. Sci., 132, 73-79.

Peng, Y., W. Lin, W. Cai, and R. Arora, 2007: Overexpression of a Pinax ginseng tonoplast aquaporin alters salt tolerance, drought tolerance and cold acclimation ability in transgenic Arabidopsis plants. Planta, 226, 729-740.

Wei, H., A.L. Dhanaraj, R. Arora, L. J. Rowland, Y. Fu and L. Sun, 2006: Identification of cold acclimation-responsive Rhododendron genes for lipid metabolism, membrane transport and lignin biosysnthesis: importance of moderately abundant ESTs in genomic studies. Plant Cell & Environment, 29, 558-570.

Arora, R., L.J. Rowland, E.L. Ogden, A.L. Dhanaraj, C.O. Marian, M.K. Ehlenfeldt, and B. Vinyard, 2004: Rate of dehardening, stage of bud opening, and changes in dehydrin metabolism in blueberry (Vaccinium spp.) cultivars during deacclimation at constant, warm temperatures. J. Amer Soc. Hort. Sci., 129, 667-674.