Low and High Temperature Influences on Cacti

摘要: The low and high temperature extremes leading to tissue damage were examined for various species of cacti. For Opuntia bigelovii, uptake a neutral red stain by its chlorenchyma cells was 50% inhibited 1-hour treatment at -7°C or 53°C, indicating the limits impairment membrane function. treatments 50$ inhibition nocturnal acid accumulation this CAM succulent -4°C 44°C, respectively. Cold hardening decrease in half-inactivation averaged 0.5°C per 10°C environmental nine Heat much greater, 4.3°C increase temperature. More negative osmotic potentials correlated with greater heat sensitivity 0. e.g., 1.0°C occurred 0.6 MPa potential. Coryphantha vivipara, essentially uninfluenced as photoperiod varied from 3 21 hours.