GROWTH, FLOWERING AND FRUIT DEVELOPMENT OF LOWLAND LITCHI CULTIVARS
Developments of leaf, inflorescence, floral and fruit of Khom, Nakhon Phanom 1, Phan Thip, Kalok Bai Khing and Hong Huai litchi cultivars were studied in Chiang Rai and Pha Yao provinces in 2009. First leaf flushing emerged in June and the second flushing emerged in August. Young folded leaf fully expanded within 20.3 days and further developed to be fully mature leaf within 18.7 days. Chlorophyll fluorescence (Fv/Fm ratio) and chlorophyll content in leaves increased as the leaves age. Fv/Fm ratio of Hong Huai leaves tended to be higher than 0.7000 and changed very little during the growth cycle. Fv/Fm ratio in leaves of lowland cultivars declined to 0.6850-0.7540 during winter period. Chlorophyll content in leaves of all cultivars changed little during annual growth and pre-flowering period which seemed to be not important for floral differentiation. Similarly, contents of total non-structural carbohydrate and total nitrogen in leaves and shoots of all cultivars seemed to be no constant changes. Inflorescences of lowland cultivars emerged in late of December or 15-20 days earlier than Hong Huai cultivar. Inflorescences reached the maximum length within 38 to 45 days after emergence. Each inflorescence produced both male and hermaphrodite as female or male flowers but the sex ratio differed among cultivars. Number of flower, flower size, blooming pattern and pollen viability also varied depending on cultivars. After fruit setting, the peel and seed differentiated within 8 days and the aril appeared in about 20 days later. Most of the massive abscission of fruitlets occurred during 1 to 20 days after pollination. The fruit matured about 68 days after setting. The development of leaves, inflorescences and fruits of all cultivars followed the sigmoidal curve of Y=a+b/(1+ex(-(x-c)/d)) which were different in cultivars.
Sukhvibul, N., Dasananda, M. and Vorapitiruangsri, S. (2014). GROWTH, FLOWERING AND FRUIT DEVELOPMENT OF LOWLAND LITCHI CULTIVARS . Acta Hortic. 1024, 163-169
Fv/Fm ratio, leaf flushing, total non-structural carbohydrate, total nitrogen