TY - JOUR

T1 - Reduced water availability improves drought tolerance of potted miniature roses

T2 - Is the ethylene pathway involved?

AU - Andersen, Lise

AU - Williams, Michelle H.

AU - Serek, Margrethe

PY - 2004/1/1

Y1 - 2004/1/1

N2 - Whilst it is possible to acclimatize roses (Rosa x hybrida) to stress by producing plants with reduced water availability, the acclimation process is not well understood. Ethylene biosynthesis is instrumental in plant senescence therefore, this investigation was carried out to determine if the ethylene pathway was influenced either by moderate drought stress during acclimation or subsequently during a postproduction wilting. During acclimation there was a clear decrease in ACC oxidase (ACO) activity in the roots. At flowering, all plants were moved to an interior room. Acclimated plants that were control watered in the interior room had increased levels of conjugated 1-aminocyclopropane-1-carboxylic acid (ACC) in root tissue compared with non-acclimated plants. Flower longevity of well-watered plants was 28-31 d irrespective of whether plants were acclimated. However, if plants experienced a postproduction wilting, then the acclimated plants clearly had the best quality. Results clearly showed that acclimated plants following wilting increased the concentration of conjugated ACC in the root tissue. This conjugation of ACC might prevent the transportation of ACC into the leaves and subsequent ethylene production. In addition, leaves of acclimated plants maintained a higher RWC, enabling them to tolerate wilting better than control leaves. Flowers developed at the end of the acclimation period and consequently did not experience the same level of acclimation as leaf and root tissues. Results show that flowers on acclimated plants were able to continue enzyme activity and senescence was not triggered irrespective of the level of endogenous ethylene.

AB - Whilst it is possible to acclimatize roses (Rosa x hybrida) to stress by producing plants with reduced water availability, the acclimation process is not well understood. Ethylene biosynthesis is instrumental in plant senescence therefore, this investigation was carried out to determine if the ethylene pathway was influenced either by moderate drought stress during acclimation or subsequently during a postproduction wilting. During acclimation there was a clear decrease in ACC oxidase (ACO) activity in the roots. At flowering, all plants were moved to an interior room. Acclimated plants that were control watered in the interior room had increased levels of conjugated 1-aminocyclopropane-1-carboxylic acid (ACC) in root tissue compared with non-acclimated plants. Flower longevity of well-watered plants was 28-31 d irrespective of whether plants were acclimated. However, if plants experienced a postproduction wilting, then the acclimated plants clearly had the best quality. Results clearly showed that acclimated plants following wilting increased the concentration of conjugated ACC in the root tissue. This conjugation of ACC might prevent the transportation of ACC into the leaves and subsequent ethylene production. In addition, leaves of acclimated plants maintained a higher RWC, enabling them to tolerate wilting better than control leaves. Flowers developed at the end of the acclimation period and consequently did not experience the same level of acclimation as leaf and root tissues. Results show that flowers on acclimated plants were able to continue enzyme activity and senescence was not triggered irrespective of the level of endogenous ethylene.

UR - http://www.scopus.com/inward/record.url?scp=1642524287&partnerID=8YFLogxK

U2 - 10.1080/14620316.2004.11511719

DO - 10.1080/14620316.2004.11511719

M3 - Article

AN - SCOPUS:1642524287

VL - 79

SP - 1

EP - 13

JO - Journal of Horticultural Science and Biotechnology

JF - Journal of Horticultural Science and Biotechnology

SN - 1462-0316

IS - 1

ER -