946 GROWTH AND DEVELOPMENTAL RESPONSES OF POINSETTA TO CALCIUM NITRATE AND TO 6-BA

Abstract

Some studies have shown that the presence of calcium ions greatly influence the growth of lateral shoots in poinsettia. Rooted cuttins were transplanted in 13.14 cm dia. plastic pots and grown on Metro-mix soil, fertilized with 20-10-S osmocote and watered as needed. Plants were sprayed with 300 & 600 ppm of ca(NO3)2. Others treated with 500 ppm of 6-BA, plus 300 and 600 ppm of Ca(NO3)2 and then with 500 ppn of 6-BA. Some plants were left without treatments as check. The average number of lateral bud breaks were highest on plants treated with 6-BA when compared to plants treated only with Ca(NO3)2 and the check. The number of lateral bud breaks increased from an average of 11 on the 5th day to 15 on the 30th day whenever 6-BA was applied. The average length of lateral shoots also increased from an average of 10mm the 5th day to over 23mn on the 30th day when 6-BA was applied, but the presence of Ca(NO3)2 at 300 ppm lateral shoot growth was greater than at 600 ppm. In general, the average growth rate in height increased in all treatments compared to the check and the presence of Ca(NO3)2 further increased the growth in height. Finally, the foliage growth rate (in diameter) was greatly influenced by 6-BA and 600 ppm of Ca(NO3)2.