บทคัดย่องานวิจัย

หมวดหมู่ : ฐานข้อมูลงานวิจัย

Yield, quality, and postharvest physiology of five rose cultivars grown under supplementary lighting.

Scott, Roger Anthony

Thesis of Ph.D., University of Guelph, Canada, 1988

1988

บทคัดย่อ

YIELD, QUALITY, AND POSTHARVEST PHYSIOLOGY OF FIVE ROSE CULTIVARS GROWN UNDER SUPPLEMENTARY LIGHTING.

The effect of supplementary lighting on the yield, quality, and postharvest physiology of five rose cultivars was studied.  In the period November to March, continuous supplementary lighting (100 umol m(-2) s(-1) from High Pressure Sodium vapour lamps) increased yields of 'Samantha', 'Royalty', 'Bridal Pink', 'Supra', and 'Golden Fantasie' by 86, 79, 86, 72 and 119%, respectively, relative to plants grown in ambient light.  Yield increases were generally not at the expense of reduced stem length except in 'Royalty'.

 Cut roses of all cultivars grown under supplementary lighting exhibited vase lives equal to or greater than did ambient light grown roses, in spite of greater postharvest transpirational water loss.  This was largely a consequence of greater leaf area and not of any differences in leaf transpiration rate or leaf diffusive resistance.  This enhanced transpiration was, however, accompanied by concomitantly greater water uptake so that flower fresh weight changes during vase evaluation were similar for any one cultivar, irrespective of the light environment during growthThis balance of water uptake and loss, and subjective vase life evaluations, were confirmed by direct measurements of changes in flower water potential during aging.  In both leaved and leafless flowers, and with or without daily recutting of the stem, the course of water potential changes were similar for cut roses of any one cultivar from either light environment.

 Postharvest ethylene production of 'Bridal Pink' and 'Samantha' flowers, but not the other cultivars, was increased in roses grown under continuous or 12 hour night supplementary lightingThis was suggested to be a possible consequence of enhanced ACC content of the petal and receptable tissue in these cultivars when grown with supplementary lighting.  Despite these differences, roses of all cultivars from either light environment responded similarly to inhibitors of ethylene action or biosynthesis.

 This study is the first to focus on the effects of supplementary lighting on the productivity and postharvest physiology of a range of rose cultivars varying widely in their growth and postharvest characteristics.