Eco-physiological Studies On Characteristics Of Blooming And Bearing In Platanus Acerifolia

The eco-physiological characteristics of blooming and bearing inplatanusacerifolia were investigated. Results were as follows: (1)most flower buds and cones existed in the external crown and apical lateral buds on one-year branches, and from apical lateral buds to lateral buds 1, 2 and 3, the proportion of female flower buds developed one or two cones is gradually decreased, while those buds of three cones is gradually increased , comparing with these , the proportion of male flower buds developed one , two and three cones is not obviously changed among 4 lateral buds. (2)The periods of development of individuals in were divided to infancy period(0-10a), youth period(10-30a) and prime period (30-80 a). Infancy period was nutrition period; Youth period was the early period of procreation growth. During this period, leaf buds' number / flower buds' number, female flower buds / male flower buds, female cones / male cones decreased with age rising; Prime period was blooming period. During this period the quantities of blooming and bearing rapidly increased with age rising, leaf buds' number / flower buds' number, female flower buds / male flower buds, female cones / male cones kept a certain low level with age rising. (3)During early youth period( 10-15 a), flower buds mainly developed to one cone's flowers, two cones' flowers took a little rate, and three cones' flowers did not develop. Over the early period, flower buds mainly developed to two cones' flowers, one cone's flowers took second place, and three Jones' flowers took the smallest ratio. Bearingfeatures of female and male parents was reflected at different development stage. (4)Male flower buds sprouted to short branches, and stopped the growth of procreation at the end of March and nutrition growth at the end of April, growth ceasing of procreation was earlier than it of nutrition; While female flower buds sprouted to long branches, and stopped the growth of procreation on October and nutrition growth at early May, growth ceasing of procreation was later than it of nutrition. (5)There werenot evident differences between Zhengzhou city and Jigong mountain in developing rates of flower buds, female buds/male buds and female cones in platanus acerifolia, the process of sprouting was almost the same, however, the trees planted in Jigong mountain had more long period of infancy, and lOdays late flowering, and largely reduced the later procreation growth. It made the diameter of cones of Jigong mountain become smaller 0.5cm, and the length of sprig become shorter 6cm. It was possible that higher temperature in summer was favorable to female cones growth and shortening of infancy period under condition of the same winter temperature. (6) Seeds of platanus acerifolia had the characteristics of shallow winter dormancy and high rate of no bearing.