Growth and Flowering of Lantana camara L. subsp. camara as Affected by Triapenthenol and Environmental Factors

Abstract

The various concentration effects of the growth regulator triapenthenol (0, 43.75, 87.5, 175, and 350 mg/pot) on the growth and flowering of Lantana camara L. subsp. camara under different shading levels (0%, 28%, and 66%) were studied in 1997 and 1998 in a glasshouse in Attica, Greece. It was found that minimum temperature and photosynthetic photon flux density were the most important factors to plant growth. The growth index (GI) decreased as the regulator concentration increased while the number of flower heads per plant increased up to a maximum at the concentration of 87.5 mg triapenthenol per pot with a decrease afterwards, at all shading levels. The interaction between shading level and triapenthenol concentration significantly affected GI and flowering of lantana plants. The growth index of the control plants increased and the number of flower heads per plant decreased significantly at all concentration levels examined, as shading increased from 0% to 66%. Triapenthenol resulted in darker green foliage and at higher concentrations in some leaf distortion. The most attractive plants were produced with triapenthenol concentration of 87.5 mg/pot at the nonshaded plot; they were small with the greatest number of flowers. Chemical name used: (E)-(RS)-1-cyclohexyl-4,4-dimethyl-2-(1H-1,2,4-triazol-1-yl)-pent-1-en-3-ol (triapenthenol).