FISH-Based Karyotype Analyses of Four Dracaena Species.

The genus Dracaena is the main source of dragon's blood, which is a plant resin and has been used as traditional medicine since ancient times in different civilizations. However, the chromosome numbers and karyotypes present in this genus remain poorly understood. In this study, fluorescence in situ hybridization (FISH) using oligonucleotide probes for ribosomal DNAs (5S and 45S rDNA) and telomeric repeats (TTTAGGG)3 was applied to analyze 4 related species: Dracaena terniflora Roxb., Dracaena cambodiana Pierre ex Gagnep., Aizong (Dracaena sp.), and Dracaena cochinchinensis (Lour.) S.C. Chen. In all 4 species, both 5S and 45S rDNA showed hybridization signals in the paracentromeric region of a pair of chromosomes; the sizes of the 45S rDNA signals were larger than those of the 5S rDNA. Importantly, the telomeric repeat signals were located in the telomeric regions of almost all chromosomes. The results indicated that the chromosome number of all 4 Dracaena species is 2n = 40, and the lengths of the mitotic metaphase chromosomes range from 0.99 to 2.98 µm. Our results provide useful cytogenetic information, which will be beneficial to future studies in genome structure of the genus Dracaena.

[Study on effect elements of anthers opening-closing movement and its cell morphology regulatory mechanism of Paris polyphylla var. yunnanensis].

In order to study the effect elements of anthers opening-closing movement of Paris polyphylla var. yunnanensis, and its cell morphology regulatory mechanism. Anthers daily opening in the morning and closing in the evening and its corresponding ecological elements changes were recorded. Different light, temperature, humidity experiment and artificial rainfall experiment were designed to observe the effect on anthers opening-closing movement, paraffin sections were made to observe the cell morphology change when the anthers daily opening and closing. The result showed that the movement of anthers daily opening and closing was regulated by ecological elements. The overall trend was high temperature and strong light, low humidity was favorable for anther opening, and low temperature, weak light, high humidity was favorable for anther closing. In this experiment, the effect of these ecological elements on the movement of anthers opening from strong to weak was humidity, temperature, light. The effect of these ecological elements on the movement of anthers closing from strong to weak was light, humidity, temperature. The direct contact of the raindrops causes the rapid closing of the anthers in the rain. Observing the cell morphology change when anthers opening and closing, it was a pollen sac dehydration and water-absorption process, different light, temperature and humidity conditions induce different physiological activities in the cell, which caused the cell osmotic pressure change, eventually resulting in anther opening and closing movement. But anthers closing caused by the rain was a simple physical adjustment process, the raindrops fell on the anthers directly, which caused anthers soaked water and change of the cell osmotic pressure, then resulting in anther closing.

[Phenotypic Trait Variation, Correlation and Path Analysis of Clerodendranthus spicatus].

OBJECTIVE: To investigate the phenotypic trait variation range of Clerodendranthus spicatus, and to look for phenotypic traits closely related with its yield and quality, in order to provide reference for its breeding. METHODS: Randomly labelled plants of Clerodendranthus spicatus, observed its phenotypic traits and analyzed by variation, principal component, correlation and path analysis. RESULTS: 13 phenotypic traits in the 15 germplasms of Clerodendranthus spicatus had great variations, the variations mainly distributed in yield, growth and genetic characteristics. Correlation and path analysis showed that, the plant dry weight had an extremely significantly positive correlation with fresh weight, and a positive correlation with stem height, stem diameter and root diameter. Plant fresh weight had a majorly direct contribution to the plant dry weight, stem height, stem diameter and root diameter also had a direct contribution to the plant dry weight. The other characters, including root length, branches, the number of leaf nodes, leaf number, leaf length, leaf width, fresh weight/dry weight ratio, rosmarinic acid content and ursolic acid content all had a negatively direct contribution to the plant dry weight. Rosmarinic acid content had a positive correlation with fresh weight, and a significantly positive correlation with fresh weight/dry weight ratio. Fresh weight had a majorly direct contribution to the rosmarinic acid content, stem height and stem diameter also had a direct contribution to the plant rosmarinic acid content. The other characters, including root length, root diameter, branches, the number of leaf nodes, leaf length, leaf width, dry weight, fresh weight/dry weight ratio, and ursolic acid content all had a negatively direct contribution to the rosmarinic acid content. CONCLUSION: The phenotypic traits of Clerodendranthus spicatus had rich variations on yield, growth and genetic characteristics. When choosing good germplasm, plant fresh weight, stem height, stem diameter and plant fresh weight/dry weight ratio having promoting effects on the plant dry weight and rosmarinic acid content should be considered comprehensively, and plant with vigorous growth, tall stem and more leaves can be choosed firstly.

[Phenotypic Trait Variation, Principal Component, Correlation and Path Analysis of Paris polyphylla var. yunnanensis].

OBJECTIVE: To investigate the phenotypic trait variation range of Paris polyphylla var. yunnanensis, and to look for phenotypic traits closely related with yield, in order to provide reference for its breeding in the future. METHODS: Wild plants of Paris polyphylla var. yunnanensis populations cultivated for three years in Xishuangbanna, Yunnan Province were chosen. The plants of Paris polyphylla var. yunnanensis were randomly labelled, its phenotypic traits were observed and analyzed by variation, principal component, correlation, variance and path analysis. RESULTS: Eleven phenotypic traits variation of the populations of Paris polyphylla var. yunnanensis were great, mainly distributed in yield, growth and genetic characteristics. Phenotypic trait of different growth years (4 - 10 years) including stem height, stem diameter, flower stem height, flower stem diameter, leaf number, leaf length and leaf width had no significant difference(P > 0. 05). The underground phenotypic traits including root weight, root length and root diameter increased significant (P <0. 05) with plant growth years. Effect of the other phenotypic traits on root weight was as follows: root diameter (0. 2550) > root growth years (0. 1183 ) > root length(0. 0202) > stem diameter(0. 0081) > stem height (0. 0044) > leaf number (0. 0025) > leaf length (0. 0018) > leaf width (0. 0004) > flower stem height (0. 0003) > flower stem diameter (0. 0001). CONCLUSION: The phenotypic traits on yield, growth and genetic characteristics have rich variations, and the phenotypic traits on the ground have no relationship with plant growth years, the plant growth years mainly affect the underground phenotypic traits. When choosing different root types, root diameter can be used as the preferred character, stem diameter as the second preferred traits when the root traits information not be easily obtained.

Mimecan, a Hormone Abundantly Expressed in Adipose Tissue, Reduced Food Intake Independently of Leptin Signaling.

Adipokines such as leptin play important roles in the regulation of energy metabolism, particularly in the control of appetite. Here, we describe a hormone, mimecan, which is abundantly expressed in adipose tissue. Mimecan was observed to inhibit food intake and reduce body weight in mice. Intraperitoneal injection of a mimecan-maltose binding protein (-MBP) complex inhibited food intake in C57BL/6J mice, which was attenuated by pretreatment with polyclonal antibody against mimecan. Notably, mimecan-MBP also induced anorexia in A(y)/a and db/db mice. Furthermore, the expression of interleukin (IL)-1ß and IL-6 was up-regulated in the hypothalamus by mimecan-MBP, as well as in N9 microglia cells by recombinant mouse mimecan. Taken together, the results suggest that mimecan is a satiety hormone in adipose tissue, and that mimecan inhibits food intake independently of leptin signaling by inducing IL-1ß and IL-6 expression in the hypothalamus.

[Occurrence situation and control strategy of Dendrobium diseases in large-scale farming system].

Artificial cultivation medical Dendrobium flourished quickly and gradually developed in a streamlined production in large scale in Zhejiang, Yunnan, Anhui, Guizhou et al provinces in recent years. As the growing years being extended and area expanded, plant disease is a growing issue and became even worse. In the current review, we summarized the available studies and the investigation in those areas on disease kinds, regular patterns, area specificity, and prevention solutions and so on. We elucidated the limitations of plant disease on medical Dendrobium planting industry development, and provided some suggestions in prevention strategy depending on the occurrence characteristics and epidemic factors. Strengthening basic research, appropriate field management and reasonable utilization of pesticide are the key part of disease integrated management

[Breeding system of Paris polyphylla var. yunnanensis].

OBJECTIVE: To provide the basic guidance for seed breeding and cross-breeding of Paris polyphylla var. yunnanensis. METHOD: The floral behavior and pollinators were observed; 0.5% TTC solution was used for the pollen viability test and benzidine and -H2O2 was used for estimation of the stigma receptivity. The mating systems were tested by out crossing index (OC1), and pollination experiment was carried out by bagged and emasculated test in the field. RESULT: Commonly, stigma lobes spread slightly, and anthers started presenting the pollen from the outer ring while the flower was just beginning to open. Consequently, the distance between the stigma and its own pollen was relatively far, this "floral behavior" may be conducive to outcrossing. Then the flower entered the later period, while the stigma lobes spread widely, anthers all split, and this "floral behavior" shortened the stigma and its own pollen's distance, which may be conducive to selfing. P. polyphylla was partly protogynous. Stigma life-span was about 10-12 d. After anther dehiscence, the pollen viability maintained about 10% within 2 days, and 20% within 10 days. The value of out crossing index (OC1) was 4. By pollination experiment and pollinators observed, P. polyphylla was self-compatible, but no capacity for autonomous self-fertilization; In natural circumstances, outcrossing fructification rate was low, and mainly anemophilous. Assisted selfing-fertilization fructification rate was higher, spider was the main pollinators. CONCLUSION: P. polyphylla has a mixed mating system with self-pollination and cross-pollination characteristics. Floral behavior has important adaptive significance in avoiding female and male interference, outcrossing, and delayed selfing. P. polyphylla is ambophily (a combination of both wind and insect pollination), pollinators changes due to environment. Pollen limitation is the main cause of low fructification rate under natural conditions.

[Identification of disease resistance to Ustilago coicis in southern Coix germplasm].

OBJECTIVE: To identified the resistance of Coix to Ustilago coicis and screen the high disease-resistance Coix germplasm. METHOD: Field and laboratory biochemical methods were used for the resistance identification. Ninteen germplasms collected from 7 provinces in southern of China such as Yunnan, Zhejiang, Fujian etc. were inoculated with chlamydospore of U. coicis, respectively. The incidence of a disease in field was investigated and the level of resistance was evaluated. The PAL activity dynamic changes in different level resistant germplasms were further determined. RESULT: The result of field test showed 1 germplasm was immune, 1 germplasm was high resistance which incidence rate was under 20%, 6 germplasms were moderate resistance with the average incidence rates ranged within 20% - 40%, 11 of 19 germplasms that average incidence rates above 40% were identified as sensitive resistance. The value of PLA activity peak of resistant germplasm in seedling was significant higher and appeared earlier than that of the sensitive ones after inoculating. CONCLUSION: Most collected C. lacryma-jobi germplasms are sensitive to smut in our investigation; the PAL activity may play important role in Coix germplasm for resistance to smut and the biochemical method may be as an aiding method to resistance identification of Coix germplasm.

[Success and problems on introduction of Scaphium lychnophorum at Xishuangbanna].

In 1970's some Scaphium lychnophorum seedlings were introduced from Kampuchea to Xishuangbanna, Yunnan Province. These seedlings have grown into the large trees and bore fruits to propagate successfully in the nature over many years. Some problems of the plant adaptability and phenological reaction to the local environment, as well as the main cultivable measures were summarized in this paper.