MICROPROPAGATION – CONTROLLED ENVIRONMENT FACILITIES AND EQUIPMENT FOR WEANING

The micropropagation of plants is now widely practised in many countries and is well documented, but the transitional period between in-vitro culture and the subsequent growth and development of a normal plant has a number of inherent problems.

The change from a highly controlled environment to one in which light level, temperature, relative humidity and growing medium are significantly different, subjects the plant to a series of stresses which are difficult to overcome.

To reduce these stresses a small weaner unit has been developed providing the following:

• greenhouse with high natural light transmission supplemented by two SON/T (high pressure sodium) lamps

• oil-filled thermostatically controlled and electrically operated tubular heaters in two banks (4.8 kw) designed to provide a temperature lift of 20°C, base temperature -10°C

• three automatically controlled roof ventilators

• two hand-operated aluminium and polyester screens to provide shade from zero to 85% and to assist in the control of temperature and energy saving

• accurate RH control by means of a four nozzle fogging system automatically controlled by an aspirated electronic humidistat linked to a control panel

• benching with capillary matting and black micro-punched polyethylene film for irrigation of the pot-grown plants.

Engineering and Economic Aspects of Energy Saving in Protected Cultivation

D.A.W. Steed

https://doi.org/10.17660/ActaHortic.1989.245.56