Ding Yu-long

A preliminary analysis of phylogenetic relationships ofArundinaria and related genera based on nucleotide sequences of nrDNA (ITS region) and cpDNA (trnL-F intergenic spacer)

Phylogenetic relationships ofArundinaria and related genera (Pleioblastus, Pseudosasa, Oligostachyum, Bashania, Clavinodum, etc.) were assessed by analyzing the sequences of the nrDNA internal transcribed spacer (ITS) and the cpDNAtrnL-F intergenic spacer (IGS). Comparison withtrnL-F IGS sequence, the ITS region provided the higher number of parsimony informative characters, and the interspecific variation of the ITS sequence was higher than that of thetrnL-FIGS sequence. The tree obtained by combining both sets of data showed that the species sampled inArundinaria and the related genera were monophyletic and divided into two clades. The relationships and positioning of all the taxa surveryed (includingA. oleosa, A. hsienchuensis, A. chino, A. amara, A. yixingensis, A. amabilis, A. fortunei, A. pygmaea, A. gramineus, A. fargesii, A. faberi, A. hupehense, Pseudosasa japonica cv. Tsutsumiana, P. japonica andBrachystachyum densiflorum) were also discussed. The results from the sequences were broadly consistent with morphological characters, appearing all these taxa sampled belong to the genus ofArundinaria. The topologies of the trees generated from individual data and the combined data were similar.

Ultracytochemical localization of peroxidase during the ground tissue development in Phyllostachys edulis (Poaceae) culms.

The Ultracytochemical localization of peroxidase during the ground tissue development in bamboo Phyllostachys edulis culm was studied with cytochemical technology.In the primary wall development period,peroxidase concentrated in the intercellular layer near the intercellular space,and then extended to all intercellular layer,and at the same time the peroxisome,endoplasmic reticulum and mitochondria also showed peroxidase activity.After that the distribution of peroxidase appeared in the tonoplast and plasma membrane.In the secondary wall development period,peroxidase activity partially increased in the long cell walls and concentrated in the narrow lamellae,especially in dormancy period.The peroxidase activity in the narrow lamellae of the long cell walls declined gradually with aging,and in nine years old culm there was little peroxidase reactive product both in the long and short cells.The short cell always had higher peroxidase activity than that of the long cell.The cell wall,plasma membrane,transfer vesicles and pits of the short cell had also shown higher peroxidase activity.A relationship between peroxidase and the differentiation of the ground tissue in bamboo culms was also discussed.

Ultracytochemical localization of Ca2+ during the phloem ganglion development in Phyllostachys edulis

Ultracytochemical localization of Ca2+ was investigated using the potassium pyroantimonate precipitation method during the development of phloem ganglion. The result showed that Ca2+ was mainly localized in the cell wall and intercellular spaces in the initiating phase. With the development of the phloem ganglion, the distribution of Ca2+ transferred to the vacuole, and the Ca2+ deposits in the cell wall and intercellular space decreased. At the later stage of the developmental phase, Ca2+ was distributed in the tonoplast and vacuole phagocytosis, and the vacuole became the main calcium storage in this phase. At the early stage of maturation of the phloem ganglion, most of the phloem ganglion cells’ vacuoles cracked, and the cytoplastic Ca2+ content increased in large number. In the mature phloem ganglion, not only were there a few Ca2+ localized in the cytoplast of mature cells, but also in the differentiating cells in the vacuoles. Ca2+ was distributed in the tonoplast and vacuole contents; initiating cells almost had no Ca2+. In general, Ca2+ concentration in mature phloem ganglion cells was at a low level. The results indicated that the changes in Ca2+ distribution evoked the phloem ganglion generation, and Ca2+ regulated the physiological function of the phloem ganglion.

Geographical Distribution of Phacellaria Benth. (Santalaceae) and its Hosts

Based on the geographical distribution of the species of Phacellaria and its host plants in the world, we speculated on the possible time, sites, and migration of the origin of Phacellaria. The host plants of Phacellaria mainly belong to Loranthaceae. Plants of Phacellaria and their hosts are mainly distributed in tropical and subtropical areas. The plants of Phacellariamight have originated from a tropical area in the south of China before the Tertiary. Their ancestors were parasitic on the ancestors of some plants of Loranthaceae by chance during the Tertiary. It possibly took them millions of years to form a sturdy relationship with their hosts.

Nutrient element contents of cutting seedlings of hybrid species (Liriodendron chinense xtulipifera)

The cutting seedlings ofLiriodendron chinense xtulipifera were treated with the different concentrations of auxin (treatment1: IBA of 50 g·kg−1+NAA of 300 g·kg−1; treatment2; IBA of 100 g·kg−1+NAA of 300 g·kg−1). The biomass nutrient element contents for different organs (root, stem, leaf) of cutting seedling ofLiriodendron chinense xtulipifera were measured by the dry method, Kjeldahl method and Atomic Absorption Spectroscopy method. The result showed that the biomass of root, stem, and leaf of the cutting seedling treated with auxin was all remarkably increased. The contents of element C in root, stem and leaf had no significant difference between the control and auxin treatments, while the contents of N, P, K and Ca in stem were much lower than that in leaf and root. Variance analysis showed that for the same organ with different concentration treatment of auxin, the four nutrient elements (N, P, K, and Ca) had no significant difference in contents, while there existed significant or very significant difference in contents of the four nutrient elements in different organs with the same concentration auxin treatment. The N, P, K and Ca contents were very low in cutting seedlings; as a result, additional fertilizer should be applied to the seedlings when they were planted in the field.