RELATIVE WATER-CONTENT AND ROOTING OF SUBIRRIGATED STEM CUTTINGS IN 4ENVIRONMENTS WITHOUT MIST

Air temperature and photosynthetically active radiation (PAR) effects on relative water content (RWC), rooting percentage, root count, and r oot mass of unmisted, subirrigated stem cuttings of two taxa were dete rmined, Leaf RWC of 'Charm' chrysanthemum [Dendranthema x grandiflorum (Ramat.) Kitamura] decreased until roots initiated and then increased , was lower for cuttings at 23 degrees C photoperiod/14 degrees C dark than for cuttings at 31 degrees C photoperiod/22 degrees C dark, and was lower at 193 than at 69 mu mol . m(-2). s(-1) PAR. Neither tempera ture nor PAR affected leaf RWC of 'Dollar Princess' fuchsia (Fuchsia x hybrida Hort. ex Vilm.), which increased linearly before and after ro ot initiation. Rooting percentage and root count were higher with phot operiods at 31 degrees C than at 23 degrees C for chrysanthemum after 7 days and for fuchsia after 10 days. Although all cuttings of both ta xa had rooted after 14 days, root dry mass was higher with photoperiod s at 31 degrees C than at 23 degrees C regardless of PAR for fuchsia a nd at 69 mu mol . m(-2). s(-1) PAR for chrysanthemum Propagators wishi ng to use subirrigation instead of mist, fog, or enclosure can minimiz e the decline in leaf RWC before root initiation and increase the numb er and dry mass of roots of chrysanthemum by using 69 mu mol . m(-2). s(-1) PAR and a 31 degrees C photoperiod/22 degrees C dark cycle. Root dry mass of fuchsia also can be increased by the use of high temperat ure, but differences in rooting were independent of changes in leaf RW C.