| Clerodendrum trochotomum Thumb is a deciduous shrub or arbor tree. It is a geographically widespread species,widely distributed in Northern, Eastern, South and Southwest provinces of China, and Japan, Korea, the Phlippines aiso has distribution. C. trochotomum Thumb with a high ornamental value, and can be widely used in urban landscape for its sprouting ability, leafy, flower-shaped chic, rich floral, long flowering and fruiting time. With its high adaptability of a variety of stress and strong resistence to drought, barren, pollution, salinity, pest and other adversities. C. trochotomum Thumb can be widely used for urban wasteland virescence, drought mining wasteland, saline areas and barren hills aforestation and vegetation restoration. Previous research on C. trochotomum is limited to physiology, reproduction, etc, But lack of morphology, cytology and molecular systematic studies, This study investigated the difference of phenology, morphology, cell and molecular biology of C. trochotomum provences,To provide a theoretical basis for breeding and genetic variability for C. trochotomum.This research based on the survy of the distribution of C. trochotomum in China According to the average annual temperature,sunshine hours, Frost-free period, precipitation and other indicators, C. trochotomum Thumb's natural distribution area was divided into six provenance areas, and at least two communities in one provenance area were selected with a comprehensive community investigation and plants individual measurement, more than 10 plants and seeds of 10 plants were collected in each of the provenances. 26 provenances in 19 provinces and rregions of China was collected, and the first provenance collection nursery of C. trochotomum was established in Shandong Agricultural University.Phenological characteristics, lmorphology feature of the provenances were studied, and karyotype and characteristics of molecular markers by AFLP was reseached to provide theoretical basis on the genetic diversity of C. trichotomum provenances. The results showed that:(1)Phenological observations showed that: The growth characteristics was similar between provences of C. trichotomum Thumb, but the blooming stage are different. The maim Phenological stage were: buds sprouting in late March, leaves full-developed in mid April to late April, branch growth mainly happened in early April to late June, and than appeared the blooming stage. Provenances of four from Henan, Anhui Shucheng, Gansu Tianshui, appeared the blooming stage in early June, mid-flowering stage in July, with a low fruiting rate. Other provenances blooming stage mainly happened in July to late October. All the provenances'blooming stage and fruiting stage were overlapped, and ornamental characteristics of flowers and fruits could be observed at the same time, which indicated that C. trichotomum Thumb. was an excellent landscape tree species.(2)Morphology observations showed that: Leaf length,leaf base shape, leaf margin ,inflorescence attachment region and calyx colour were different between provenances. Leaf base shape of the provences except ones from Nanjing, Lianyungang, Lianyungang, Xinxian County, Luoning, Xixia County, Luanchuan County, Tianshui and Taigu County presented a changing range from heart-shaped to wedge, and othere provenances showed a heart-shaped leaf base shape. The leaf margin of the provenances of Luoning County, Xixia County, Chuan County, Tianshui, and Taigu County is serrated, provenances of Lianyungang, Lianyungang, Nanjing showed a nearly entire leaf margin, the other provenances showed a blunt dentate leaf margin. Calyx colors in full bloom are quite different that provenances from Xinxian County, Luoning County, Xixia County, Luanchuan County, Tianshui and Taigu County appeared bright green calyx, provenances from Nanjing and Lianyungang appeared green colour in bottom calyx and light red colour in upper calyx, the other provenances appeared pink blossom calyx. Inflorescence length in full blooming stage was different between provenances that the largest is about 31 cm from the provenances of Lianyungang and Nanjing with 120 flowers, the smallest is about 13 cm from Tianshui provenance with about 50 flowers, the medium is about 28 cm from Shandong provenances with 200 flowers.(3)Karyotype analysis showed that: The karyotype of forteen provenances was studied by method of squash with the sprouting buds and found that the chromosomes of all forteen provenances were diploid. The karyotypes were divided into five types, that is 2 n=2 x=52=36 m+16 sm,2 n=2 x=40 m+12 sm,2 n=2 x=46 m+6 sm,2 n=2 x=48 m+4 sm,2 n=2 x=44 m+8 sm. There was no satellite found in the morphological observation of chromosomes. The average of chromosome absolute length on forteen provenances was 1.45μm, belong to small karyotype. The karyotype of the forteen provenances was all belonged to 2 B type except 021, which is 2 A type.(4) Molecular marker studies shown that: Genetic diversity of twenty six provences was analysied by AFLP molecular markers, 8 pairs of primers were usd and 1728 roads amplified, and a more extensive genetic diversity with 1728 sites were detected, of which 972 were polymorphic. There is significant correction between geographical proximity of the sources and most provenances are gathered in one class which are close in location.
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