A two- year field experiment was carried out during two successive seasons of 2006/2007 & 2007/2008 to study the effect of light intensity i.e., under full sun light conditions: more than 25000 lux. or under lathhouse conditions: 8600-9800 lux., kinetin treatments which sprayed at the concentrations of 50, 100 and 150 ppm and their combinations on the growth, flowering and chemical composition of Clivia miniata plants . The results showed that plant height, number of leaves and off sets, length, width and fresh weight of leaf was greatly increased with grown clivia plants under shade conditions as compared with those grown under full sun light conditions. Also, all tested applications of kinetin increased the studied vegetative growth traits, especially using the highest concentration. Moreover, all combinations between light intensity and kinetin treatments caused increments in vegetative growth traits. However, the highest values of vegetative growth traits were obtained by 150ppm kinetin sprayed plants grown under shade conditions. Grown clivia plants under shade conditions showed to be the most promising one in inducing the earliest flowering as compared with those grown under full sun light conditions. Likewise, 100ppm kinetin-sprayed plants induced the highest precocity in this parameter. However, 100ppm kinetin-sprayed plants grown under shade condition recorded the lowest number of days to start flowering. Generally, the highest values of number of flower/plant, number of florets/flower, length, width and fresh weight of flower were obtained by grown clivia plants under shade condition and sprayed with kinetin at 150ppm.
In anatomical studies, As for the leaf structure is quite evident that an obvious increase was resulted by the shade condition compared with the plants grown under full sun light and icreased these value due to kinetin foliar spray. Meanwhile, the thickness of cutical and epidermis layers and vascular tissue were increased in compared with the plants grown under full sun light. In epidermal characteristics increased the epidermal cell dimention, stomata dimentiom and No. Of open stomata ( in area 360 µ. Meanwhile, the same characteristics are decreased in the plants grown under full sun light with increased the total number of stomata and No. Of closed stomata in same area(360 µ) and the best values in anatomical structure of leaf were the shade condition and sprayed with kinetin at 150ppm.
The greater leaf N, P, K, total chlorophylls and total indoles contents as well as the lowest leaf total phenols content were recorded by 150ppm kinetin-sprayed plants grown under shade conditions.