ISSN: 0041-3216

ISSN: 0041-3216 (Online), 0041-3216 (Print)
Volume 79 Number 3
Research Notes
Use of natural acclimatizing environments for the ex-vitro establishment of micro-propagated grapes (Vitis vinifera L.). (180)
With a view to test if resource-saving natural environments could be exploited for the acclimatization and ex-vitro establishment of micro-propagated plantlets, in-vitro rooted grapes (Vitis vinifera L.) var. Arka Neelamani, planted in ployethylene sachets were incubated under six environments. These consisted of a hardening rack housed inside a building with provision for 16-h light supply [fluorescent tubes giving a photosynthetically active radiation (PAR) of 30-40 ?mol quanta m-2 s-1] (E1), the courtyard of a building with no direct sunlight on the sachets (E2), a glasshouse under tree shade with diffused light (E3), a glasshouse under full sun with bright light (E4), the shade of a Singapore cherry tree (E5), and open air-full sun (E6). These environments could be defined in terms of temperature, light intensity, duration of light, and ambient relative humidity (RH). The net plant establishment at eight weeks from in-vitro planting were 91, 81, 38, 43, 81, and 0%, respectively, under the six environments. The environments E2 and E5 with PAR in the range of 20-120 ?mol m-2 s-1 were identified as worthy enough to substitute for the infrastructure and energy requirements of E1, the common acclimatizing environment. From the observations, it is concluded that acclimatization of micropropagated grapes employing the sachet technique could be accomplished under natural conditions (temperature 25-32°C) by reducing the light intensity to 50-150 ?mol m-2 s-1 using shade nets.
Keywords: Acclimatization; In-vitro; Light intensity; Micro-propagation; Relative humidity; Resource saving; Temperature