Tomato rootstocks contribute to abiotic stress tolerance: emphasis on root chill tolerance

S.T. Bristow, L. Hernandez, F.H. Barrios-Masias
Low soil temperatures affect root establishment, growth, nutrient and water uptake, hampering shoot growth and delaying harvest. Growers in northern latitudes and higher elevations such as in northern Nevada face, during the spring, adequate day air temperatures, but sub-optimal soil temperatures (≤15°C) for several summer crops. To adapt and optimize warm-vegetable production early in the season, growers could rely on the use of low-temperature tolerant rootstocks, yet information on which and how rootstocks can improve management strategies does not exist. We evaluated four commercial tomato rootstocks (Estamino, Maxifort, RST-04-106T and Supernatural) grafted with a common scion and the ungrafted scion/cultivar (BHN589) under prolonged chilling stress. Additionally, three of these commercial rootstocks (Estamino, Maxifort, and Supernatural) and the ungrafted cultivar 'Early Girl' were evaluated under short-term chilling stress. Several root and shoot physiological traits were evaluated under suboptimal and control root temperatures for both lengths of exposure. Root hydraulic conductivity (Lp) decreased in roots exposed to cold temperatures for prolonged periods, but some rootstocks were able to maintain higher root hydrostatic Lp. Changes in root osmotic Lp were not observed among the different root systems under prolonged exposure, but decreased for all root systems under brief exposure. Our data suggests that length of exposure to chilling temperatures plays a role in plant responses, and should be considered when evaluating rootstock for root chill tolerance.
Bristow, S.T., Hernandez, L. and Barrios-Masias, F.H. (2021). Tomato rootstocks contribute to abiotic stress tolerance: emphasis on root chill tolerance. Acta Hortic. 1302, 193-200
DOI: 10.17660/ActaHortic.2021.1302.26
suboptimal soil temperature, hydraulic conductivity, stomatal conductance, Solanum lycopersicum

Acta Horticulturae