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Physiological and anatomical investigations of two species of Liatris
Abstract
Overall growth and development of many plants are influenced by photoperiod and growth regulator treatments. Two studies were conducted to evaluate the effects of 3 photoperiod regimes and 2 growth regulators on top and corm growth of seedlings of Liatris pycnostachya Michx. and L. aspera Michx. under greenhouse and field conditions. A third study was also conducted to determine time of inflorescence development of L. pycnostrachya Michx. plants grown from corms. The first study evaluated the effects of photoperiod regimes and growth regulators on growth and development of Liatris pycnostachya Michx. and L. aspera Michx. under greenhouse and field conditions. Top and corm growth of seedlings of both species were influenced significantly by photoperiod regimes and growth regulator treatments. Seedlings subjected to LD for 5 months (16 her) and LD (16 hr) for 2$1\over2$ months/SD (9 hr) for 2$1\over2$ months were superior to those grown under a SD (9 hr) photoperiod of 5 months. Gibberellic acid (GA$\sb3$) treatments generally promoted top growth and reduced corm growth. Succinamic acid 2,2-dimethylhydrazide (SADH) exhibited the opposite effect. Corms which were subjected to LD, LD/SD, and/or SADH treatments produced the highest yield of superior quality cut flowers. The second study examined the influence of GA$\sb3$ and SADH treatments on the performance of seedling propagules of the two species under field conditions. GA$\sb3$ promoted vegatative growth, increased yield of flowering stalks, and enhanced corm size and weight considerably. SADH had no apparent effect on the rosette-type of growth and/or corm development of L. pycnostachya, but it reduced stalk and spike lengths of L. aspera and improved flower color and quality. The third study was a morphological and anatomical investigation that described the developmental sequences and events leading to flowering of L. pycnostachya plants. This species needed a total of 16 weeks to reach a stage of maturation suitable for cut flower production. The plants were in a vegetative stage during the first 8 weeks of growth. The transition from vegetative to reproductive stage of growth took place between the 8th and 9th week after planting. The reproductive stage during the remaining 7 to 8 weeks was associated with flower initiation, differentiation, and maturation. (Abstract shortened with permission of author.)
Subject Area
Botany
Recommended Citation
El-Naggar, Abdel-Razek I, "Physiological and anatomical investigations of two species of Liatris" (1988). ETD collection for University of Nebraska-Lincoln. AAI8824926.
https://digitalcommons.unl.edu/dissertations/AAI8824926