The Status of Dipterocarpaceae Plants in Taiwan

The Dipterocarpaceae family is famous for timber productions in Southeast Asia. The Shuangxi tropical arboretum in Taiwan introduced some dipterocarp species in 1935. However, the changes in abundance and regeneration of each dipterocarp species are unknown. This study aimed to investigate their diameters patterns and regeneration ability over a long period. The results showed that only four dipterocarp species were survived in this arboretum. An individual plant of Dipterocarpus gracilis Blume had a diameter of 5.7 cm. A young seedling was 90 cm in height, and some fruits germinated directly on the ground. A few fruits of Dipterocarpus grandiflorus (Blanco) Blanco were collected;however, and no seedlings have been found thus far, and its annual growth rate was 2.82% as the fastest growth speed. The annual growth rate of Rubroshorea polysperma (Blanco) P. S. Ashton & J. Heck was 2.32%, which is the second growth speed among the different species. Moreover, the abundance of R. polysperma increased as the fruits germinated. In particular, an uneven-aged forest of R. polysperma was established near the southwest area of the No. 2225 nature conservation protection forest, and an individual with a 100 cm DBH was also found. The fruits of Rubroshorea palosapis (Blanco) P. S. Ashton & J. Heck. could not be collected, but a young seedling appeared, with a height of approximately 150 cm. Therefore, Taiwan should be considered as the new distribution site for the Dipterocarpaceae family, all four dipterocarp species can grow in this area and need to be protected carefully.

A Novel Segregation Distortion in Intraspecific Population of Asian Cotton(Gossypium arboretum L.)Detected by Molecular Markers

The segregation ratio of markers in an F2 population derived from Rudongjijiaoyaguo （Rdjjyg） and Zhongmian971 （Zm971） was studied using 3 morphological markers, 20 SSR markers, and ll SRAP markers. Totally, 24 markers （77.42%） showed a distorted segregation and all of them skewed toward the female genotype, which was peculiar in recent cotton research. All the three types of SSR markers and SRAP marker showed distorted segregation, but the morphological markers （Purple stem, Okra leaf, and Red spot color） were normally segregated. This indicated that such a novel segregation distortion phenomenon resulted from interior genetic factors, The allele frequency and the distribution of different genotype frequencies in the F2 population were analyzed in codominant markers, to find out factors attributed to distorted segregation. Most of them implied distorted allele frequency, but it was normal genotype frequency, which showed that these markers were influenced at the gamete level.

A microsatellite study on outcrossing rates and contamination in an Eucalyptus globulus breeding arboretum

Four pairs of microsatellite molecular polymorphism primers were used to analyse microsatellite fingerprints of 188 seedlings derived from an open-pollinated progeny grafted Eucalyptus globulus breeding arboretum in Victoria, south-eastern Australia. The microsatellite loci chosen for this study were highly polymorphic with the mean number of alleles per locus of 14.25. Individual mothers varied in their outcrosssing rate estimate from 15% to 95%, the overall outcrossing level in the arboretum was 47.9% and the contamination rate was 17.6%. The high selfing level was likely to result in marked inbreeding depression in the performance of open-pollinated seed lots. Open-pollinated seeds collected from such arboreta are not advisable because of its low genetic quality, although such arboreta may be useful for the seed production through large-scale manual pollination or collecting seeds only from trees or genotypes within the arboretum that have high outcrossing rates.

Growth, Physiological and Molecular Responses of Cotton (Gossypium arboreum L.) under NaCl Stress

Salinity is one of the most serious growth limiting factor, therefore, no longer being ignored. Although, cotton is fairly salt tolerant;its sensitivity at crop stand and yield is affected. This study is planned to identify the growth, physiological and molecular parameters in local cotton varieties FDH 171 and FDH 786 under NaCl stress. There was 100% seed germination but hypocotyl length was reduced at increasing level of NaCl. Plant height, fresh and dry biomass were reduced as the plants were subjected to increased stress of NaCl. Stomatal conductance, transpiration and photosynthetic rate and ionic imbalance were found to be reduced under the gradual increase in NaCl stress and affected the plant’s overall physiological processes. PCR product of AtNHX3 has been identified in stressed and non-stressed plants. Thus, the genotypes FDH 171 & FDH 786 were found tolerant to adoption of salt stress and could be used as a source in crop improvement.

<i>Abies sibirica</i>Male Reproductive Cones Developmental Shift at Introduction

A strong effect of climate on phenological events in conifers has been documented by several studies. To study adaptation of reproductive processes in Abies sibirica Ledeb. to changing environment, the phenology of the development of the species male reproductive cones at introduction was studied. Phenological shift in Abies sibirica meiosis and pollination was observed. An earlier start of male bud reproductive development is founded in V.N. Sukachev Institute of Forest Arboretum resulted in increasing meiosis and pollen irregularities. Insufficient high quality pollen in the species at its pollination stage may be a major factor responsible for the incapability to produce the viable seeds in quantities sufficient for pollination in seed gardens. Responses of the fir male cone development to the current environmental conditions at the Arboretum may be considered as a model of adaptation of the species to climatic changes.

Enlightenment from the Construction of American Botanic Gardens:A Case Study of The Morton Arboretum

Starting from reviewing the current development of botanic gardens in China,the shortcomings of current research on botanical gardens in China are summarized:the research and construction concepts of the botanical gardens lack professional characteristics;the education and science popularization system is extensive;and the investment and construction model and operation and management method are relatively rigid.Through combing the development history of The Morton Arboretum and introducing its construction features,such as the long-term garden-establishing idea with a high starting point,continuously building and improving for a long time to actively adapt to changes in social needs,a refi ned education and science popularization system for various groups,and a strong self-hematopoietic function,the successful construction experience of The Morton Arboretum is elaborated and the enlightenment from The Morton Arboretum to the construction of botanic gardens China are put forward,so as to provide a reference for the construction and development of botanic gardens in China in the new period.

亚洲棉NF-YA基因家族的全基因组鉴定及表达分析

NF-YA家族基因在植物生长发育过程中发挥重要作用,如调控种子发育和种子萌发,响应干旱和盐胁迫等。本研究利用生物信息学手段从亚洲棉全基因组鉴定NF-YA家族基因,并从理化性质、基因的内含子和外显子结构、氨基酸序列的功能结构域、系统进化发育特征、在染色体的分布和表达模式等方面分析了该家族基因的特征。结果表明:GaNF-YA包含15个成员,分布在9条染色体上,编码蛋白质长度为160~1079个氨基酸,相对分子质量为17.92~120.30 kD,包含外显子4~6个,为碱性。亚洲棉NF-YA基因可分为三组,且三组NF-YA基因结构存在差异,保守基序分析其均含有A1和A2结构域。通过对启动子顺式作用元件和表达谱分析,推测GaNF-YA基因可能在棉花种子和纤维形成、种子萌发及环境胁迫等中具有重要作用。本研究为进一步解析亚洲棉NF-YA家族基因的功能提供理论依据。