Effects of water stress, shading and clipping on growth and development of Asystasia gangetica
Ismail B. Sahid and A. Shukor Juraimi, Department of Botany, Universiti Kebangsaan Malaysia, 43600 UKM, Bangi, Selangor, Malaysia.
Greenhouse and field experiments were conducted to determine the effects of watering frequency, drought stress, shade and clipping on the growth and development of Asystasia gangetica (L.) T.Anders. Plants grown from seeds in the field took a longer time to flower and fruit than those grown under greenhouse conditions. Leaf area was not affected significantly as shade levels increased. Shoot and root dry weight and number of flowers and fruit decreased as light decreased. Numbers of flowers and fruit and shoot and root dry weight increased when plants were watered more frequently. A 10 day dry period significantly reduced shoot and root dry weight compared with those of plants watered daily. After clipping at 4-12 weeks after emergence all plants regrew. Shoot dry weight and number of flowers and fruits increased when clipping was carried out 12 weeks after emergence, although flowering and fruiting was delayed.
Plant Protection Quarterly (1998) 13 (3) 140-142.