Preliminary Study On Flowering Biological Characteristics And Pollen Grain Morphology Of Sect.Chrysantha Chang

Sect.Chrysantha Chang is the only yellow in the Camellia,which is very characteristic and mainly distributed in Guangxi,China.In addition to ornamental value,Camellia chrysantha also has edible value and medicinal value.Based on this,this paper studies the floral morphology,flowering phenology,pollen grain morphology and flower bud differentiation of Sect.Chrysantha Chang in Nanning Camellia chrysantha Park gene bank by means of vernier calipers,scanning electron microscopy and paraffin section,and tries to explore the biological characteristics of flowering and pollen grain morphology of Sect.Chrysantha Chang from surface to inside.The florescence regulation,classification and garden application of the group plants provide scientific reference.Through the research,the following main conclusions are obtained:1)10 indexes of flower morphological characteristics of Sect.Chrysantha Chang have certain correlation.Bud diameter was positively correlated with corolla diameter,while bud length was positively correlated with corolla height and petal length.In color,there are light yellow,medium yellow,yellow,golden and other four colors.In flower pattern,there are small flowers,medium flowers,large flowers and other flower patterns.2)Flowering duration of 10 species of Sect.Chrysantha Chang population ranged from 24 to 55 days,including 10 to 26 days at full bloom stage,3.58 to 6,37 days at single flower stage and 3 to 8 days at single flower stage,of which 5 days,6 days and 7 days were dominant.3)The pollen grains of 10 species of Sect.Chrysantha Chang are between(48.86-27.29)[im and(26.59-37.12)?m in size.The pollen grains are nearly spherical and oblate in shape.The polar view is triangular or triangular with 3(pseudo)holes and grooves.The surface decorations are smooth wart-like corrugation,rough wart-like granulation and rough worm-like decoration.Cluster analysis showed that the relationship between Camellia ptilosperm and Camellia tunghinensis was relatively close,and that between Camellia achrysantha and Camellia chuangtsoensis was relatively close,while that between Camellia nitidissima and Camellia euphlebia was relatively far.4)According to the characteristics of Camellia nitidissima flower buds,the conventional paraffin section technology was optimized and improved:before dehydration,scales were peeled off and distilled water soaked for 2 hours;dehydration time was 3 hours at all levels,alcohol and transparent agent time was 45 minutes,transparent agent was 30 minutes,twice.Wax immersion with a small amount of wax chips added many times.The optimized slicing technique is suitable for different kinds of camellia flower bud slices.5)Flower bud differentiation is about 1 month in Camellia chuangtsoensis,2 months in Camellia ptilosperm and 3 months in Camellia nitidissima.Flower bud differentiation of Camellia chrysantha and Camellia ptilosperm in Camellia chuangtsoensis can be carried out all year round,and Camellia chrysantha can only differentiate once a year.6)According to the morphological characteristics of flower bud differentiation,the flower bud differentiation of Camellia chuangtsoensis,Camellia ptilosperm and Camellia nitidissima were divided into seven stages:undifferentiated stage,initial stage of differentiation,sepal differentiation stage,petal differentiation stage,stamen differentiation stage,pistil differentiation stage and ovary formation stage.Overlapping phenomena appeared in different differentiation stages.