Abstract
We investigated the effects of flower bearing types and pinching methods on the characteristics of water consumption in winter-spring harvest cropping type of carnation (Dianthus caryophyllus L.) in order to develop liquid fertilizer management of cultivation by fertigation. The standard type ‘Nora’ and spray type ‘Barbara’ were cultivated by bottom fertigation with single pinching or double pinching. The amount of daily water consumption changed with cultivation time, the amount of daily water consumption was lowest in summer for the early cultivation time and greatest in spring for the later cultivation time. The total amount of water consumption for ‘Nora’ grown by single pinching was 32.29 L (per plant), that of ‘Nora’ grown by double pinching was 35.26 L, that of ‘Barbara’ grown by single pinching was 29.75 L and that of ‘Barbara’ grown by double pinching was 30.29 L. There was a positive correlation between the amount of water consumption over 4 weeks and the number of leaves during those 4 weeks. There was a positive correlation between the amount of daily water consumption and the daily integrated solar radiation 4 weeks after planting. The amount of water consumption (y: L·plant−1·4 weeks−1) could be estimated by a regression line between the integrated solar radiation (X1: MJ·m−2·4 weeks−1) and the leaf number at that time (X2: per plant) as follows; y = 0.00697X1 + 0.00930X2 − 1.36616, regardless of cultivar or pinching methods. Moreover, the amount of water consumption could be estimated by solar radiation alone starting 12 weeks after planting.
