Species of associated bryophytes and their effects on the yield and quality of Dendrobium nobile.

BACKGROUND: Dendrobium nobile has unique growth environment requirements, and unstable yields and high management costs are the key factors restricting the development of its imitation wild cultivation industry. The present study explored the effects of different associated bryophyte species on the yield and quality of D. nobile to clarify the dominant bryophyte species associated with D. nobile and to provide a scientific basis for the rational cultivation and quality evaluation of D. nobile. RESULTS: The growth of D. nobile was closely related to the microenvironment of the Danxia stone, and the different associated bryophytes had different effects on D. nobile growth. There was a rich variety of bryophytes associated with D. nobile, with a total of 15 families, 24 genera and 31 species of bryophytes identified in the study area, including 13 families, 22 genera and 29 species of mosses and 2 families, 2 genera and 2 species of liverworts, and mosses predominated in the association with D. nobile. Usually, 3-9 species of bryophytes were growing in association with D. nobile, among which associations of 5-6 bryophytes species were more common, and the bryophytes associated with D. nobile were only related to the species to which they belonged. The dry matter accumulation, quality and mineral content of D. nobile differed significantly among different bryophyte species. The coefficients of variation of dry matter accumulation, dendrobine content and content of 11 mineral elements of D. nobile in the 35 sample quadrats were 25.00%, 21.08%, and 11.33-57.96%, respectively. The biomass, dendrobine content and mineral content of D. nobile were analysed by principal component analysis (PCA) and membership function. The results showed that each evaluation method initially screened Trachycystis microphylla and Leucobryum juniperoideum as the dominant associated bryophytes in the preliminary identification analysis, and the frequency of occurrence and coverage of the two bryophytes were significantly higher than those of the remaining bryophytes. It was determined that T. microphylla and L. juniperoideum were the dominant associated bryophytes. CONCLUSIONS: There is a rich variety of bryophytes associated with D. nobile. The yield and quality of D. nobile differed significantly among different bryophyte species. T. microphylla and L. juniperoideum were the dominant associated bryophytes, and were the two bryophytes associated with D. nobile through mixed growth.

[Discrimination of cultivation modes of Dendrobium nobile based on content of mineral elements and ratios of nitrogen stable isotopes].

This study explored the feasibility of mineral element content and ratios of nitrogen isotopes to discriminate the cultivation mode of Dendrobium nobile in order to provide theoretical support for the discrimination of the cultivation mode of D. nobile. The content of 11 mineral elements(N, K, Ca, P, Mg, Na, Fe, Cu, Zn, Mn, and B) and nitrogen isotope ratios in D. nobile and its substrate samples in three cultivation methods(greenhouse cultivation, tree-attached cultivation, and stone-attached cultivation) were determined. According to the analysis of variance, principal component analysis, and stepwise discriminant analysis, the samples of different cultivation types were classified. The results showed that the nitrogen isotope ratios and the content of elements except for Zn were significantly different among different cultivation types of D. nobile(P<0.05). The results of correlation analysis showed that the nitrogen isotope ratios, mineral element content, and effective component content in D. nobile were correlated with the nitrogen isotope ratio and mineral element content in the corresponding substrate samples to varying degrees. Principal component analysis can preliminarily classify the samples of D. nobile, but some samples overlapped. Through stepwise discriminant analysis, six indicators, including δ~(15)N, K, Cu, P, Na, and Ca, were screened out, which could be used to establish the discriminant model of D. nobile cultivation methods, and the overall correct discrimination rates after back-substitution test, cross-check, and external validation were all 100%. Therefore, nitrogen isotope ratios and mineral element fingerprints combined with multivariate statistical analysis could effectively discriminate the cultivation types of D. nobile. The results of this study provide a new method for the identification of the cultivation type and production area of D. nobile and an experimental basis for the quality evaluation and quality control of D. nobile.

[Effect of Plant Density and Harvest on Yield and Quality in Blumea balsamifera].

Objective: To study the effects of different plant density and harvest time on the yield and quality of Miao medicine Blumea balsamifera, in order to provide a theoretical basis for Good Agriculture Practice( GAP). Methods: Two factors trails were used to research the influence of plant density and harvest time on the yield and quality of Blumea balsamifera. The plant density were located at 50 cm × 90 cm,50 cm × 60 cm,50 cm × 30 cm and 30 cm × 30 cm, and the harvest time were set up at mid-October, mid-November and mid-December. The experiments were designed with randomized block design. Results: Yield and quality were both affected by the plant density and harvest time. Yield per unit area and volatile oil yield per unit area were increased significantly with the increasing of plant density. Yield per unit area and volatile oil yield per unit area were peaked at the plant density of 111 112 plants / hm~2 which could obtain high-yield at the mid-December, which were 1 546. 68 kg / hm~2 and 96. 6 L / hm~2,respectively. The content of total flavonoids were peaked at the plant density of 22 223 plants / hm~2 and 111 112 plants / hm~2,which were 2. 50 and 2. 53 mg/g,respectively. Harvest time had no significant effect on the flavonoids content. Conclusion: The suitable plant density of transplanted root tillers of Blumea balsamifera is 111 112 plants / hm~2 and the optimum harvest time is December.

[Comparative Analysis of Main Morphological Characters and Interrelationship in Blumea balsamifera].

Objective: To investigate the main morphological characters and interrelationship of Blumea bdsamifera, and to provide the guidance for selection and breeding of Blumea balsamifera. Methods: 19 main morphological characters and their interrelationship were analyzed by using correlation analysis,multiple stepwise regression analysis and factor analysis. Results: Variation coefficients of the morphological characters were big in Blumea balsamifera. Correlation coefficients for morphological characters were significant( P <0. 05 or P < 0. 01). Using factor analysis,19 morphological characters were classified into six principal divisors. Ten morphological characters, including length / wide of leaf,trunk diameter, leaf number of second branch, leaf number of first branch, number of trunk leaf, weight of strong leaf, weight of young leaf,weight of old leaf, number of first branch, leaf number of whole plant, were the main factors which influenced the weight of whole plant leaf. Conclusion: The variation of every morphological character of Blumea balsamifera is abundant in different population, and a certain correlation is existed among morphological characters. The morphological characters, length / wide of leaf, trunk diameter, number of first branch, number and weight of leaf, are the main factors which influenced the weight of whole plant leaf.

[Content of mineral elements of Gastrodia elata by principal components analysis].

OBJECTIVE: To study the content of mineral elements and the principal components in Gastrodia elata. METHOD: Mineral elements were determined by ICP and the data was analyzed by SPSS. RESULT: K element has the highest content-and the average content was 15.31 g x kg(-1). The average content of N element was 8.99 g x kg(-1), followed by K element. The coefficient of variation of K and N was small, but the Mn was the biggest with 51.39%. The highly significant positive correlation was found among N, P and K . Three principal components were selected by principal components analysis to evaluate the quality of G. elata. P, B, N, K, Cu, Mn, Fe and Mg were the characteristic elements of G. elata. CONCLUSION: The content of K and N elements was higher and relatively stable. The variation of Mn content was biggest. The quality of G. elata in Guizhou and Yunnan was better from the perspective of mineral elements.

[Effects of Different Planting Direction and Layer Combination on Gastrodia elata f. elata in Bionic Wild Cultivation].

OBJECTIVE: Combination of different planting direction and layer were set to choose the best technology of cultivation of Gastrodia elata f. elata. METHODS: To improve the yield and quality of Gastrodia elata f. elata, randomized block design experiments were carried out to investigate the yield and quality, and to analyze their economic effectiveness in bionic wild cultivation. RESULTS: Length, width, thickness and weight of southern direction's Gastrodia elata f. elata developed better than the northeast direction. The three planting layer levels on growth effect of Gastrodia elata f. elata was the 3rd layer > the 2nd layer > the 1st layer. In six treatments, combination of southern direction-the 3rd layer was the best technology of cultivation of Gastrodia elata f. elata, which had the best growth condition, the highest yield significantly higher than other treatments, and the best economic benefits. CONCLUSION: Southern direction associated with the 3rd layer is the best combination to planting Gastrodia elata f. elata in bionic wild cultivation. The planting ways not only improve the yield and quality, but also save land.

[Research on life history and phenological period of wild-stimulated cultivated Gastrodia elata f. elata in Guizhou].

In order to get to know the imitation of wild Gastrodia elata in life history and phenology period, by G. elata f. elata forest wild simulated cultivation in Dafang county, Guizhou province, observing and recording its morphological characteristics of each growth and development stage. This experiment summarized the law of its life history over 24 months, amplified the characteristics of each 5 phenology periods over the sexual and asexual reproduction of wild simulated cultivated G. elata f. elata in Guizhou. Which the results could clear the process of wild simulated cultivated G. elata f. elata in Guizhou, and provide a theoretical support for the standard technical of the simulated wild G. elata.

[Study on seeds dormancy release and physiological change of Thesium chinense].

OBJECTIVE: To study the seeds dormancy release and physiological change of Thesium chinense. METHOD: To release dormancy, the seeds of T. chinense were treated with chemical reagent and stratification under 3-5 degrees C. RESULT: When washed with flowing water for 24 h, then soaked in 500 mg x L(-1) GA3 for 24 h, finally, treated with stratification method under 3-5 degrees C for 150 day, the split rate of T. chinense seeds reached 22%, crude fat decreased 50%, total sugar and dissolvability sugar increased 3-4 times, ABA decreased more than 90%, GA3 increased more than 5 times. CONCLUSION: The seeds dormancy of T. chinense can be released with the method of washing with flowing water for 24 h, then soaking in 500 mg x L(-1) GA3 for 24 h, finally, treated with stratification method under 3-5 degrees C for 150-180 day.

[Study on biological characteristics of Thesium chinense].

OBJECTIVE: To study the biological and growth characteristics of Thesium chinense. METHOD: The wild population was observed in certain sites, pot and indoor experiments were applied for cultivated plant. RESULT AND CONCLUSION: T. chinense is an obligate root hemiparasite and perennial herb, stem and leaf were green, there were haustoriums on its root, can only achieve its whole life process when parasitized to host. T. chinense grows mostly in the humid wasteland and herbaceous community where water is generally abundant. T. chinense likes light, warm climate and acidic to neuter soil. The seeds of T. chinense have dormancy characteristics. The life history of T. chinense can divide into 5 stages: seedling, ramify, florescence, fructification and withering periods.

[Study on hemiparasitic mechanism of Thesium chinense].

OBJECTIVE: To study the hemiparasitic mechanism of Thesium chinense. METHOD: The anatomical structure of T. chinense was studied by using paraffin slice and electron microscope slice. Chlorophyll content was measured by UV spectrometry. Foliar photosynthesis (P(n)) and gas exchange were measured by using a LI-6400 photosynthesis system. RESULT: Chloroplast possesses intact granal thylakoid system, lamella was strong. Vascular tissue of T. chinense was strong. Vessel aperture and its transport power were strong both in root and stem. There were many global haustoriums on lateral roots. Vascular tissues were strong inside haustorium, haustorial stylet penetrated epidermis and cortex of host root, and reached pith place, haustorial vessel was integrated with host root vessel. The maximum of P(n) of T. chinense reached 7.06 micromol x m(-2) x s(-1), its water use efficiency was lower, about 0.735 mmol x mol(-1), its transpiration varied notable in daytime and was relatively invariant at nighttime, and the value of daytime was greatly exceed that of nighttime. CONCLUSION: T. chinense despoils water and nutrition from its host by haustorium. T. chinense can mostly be independent as for C supply by photosynthesis.

[Complex evaluation for influence of hosts on hemipatasite Thesium chinense].

OBJECTIVE: To study the influence of host species on growth and development and active component content of Thesium chinense. METHOD: Plant morphology and active component content of T. chinense grown with different hosts were measured. The hosts were evaluated by using index-sum method. RESULT: Hosts significantly promoted the growth of T. chinense by increasing height, per plant weight, stem diameter, leaf area, the number of seed and haustorium,and decreased RW/SW ratio compared to without host treatment. Considerable differences existed among the effect of different host species treatments. Synthetical evaluation score of Gnaphlium affine was the highest (37), followed by Imperata cylindrical and Prunella vulgaris (36). It is suggested that they were superior hosts for T. chinense. But the scores of Triticum aestivum (25) and Eremochloa ophiuroides (17) were lower, so they were unsuited hosts for T. chinense. CONCLUSION: Hosts significantly promoted the growth of T. chinense. Considerable differences existed among the growth and development of T. chinense grown with different hosts, as well as active component content. Gnaphlium affine, Imperata cylindrical and Prunella vulgaris were superior hosts for T. chinense. While Triticum aestivum and Eremochloa ophiuroides were unsuited hosts for T. chinense.

[Study on germination characteristics of Disporum cantoniense].

OBJECTIVE: To study the seed germination characteristic and optimal germination condition of wild Disporum cantoniense. METHODS: Used wild Disporum cantoniense seed as the test materials, the rate of water absorption of the seed was determined. The germination rates under different conditions, along a temperature gradient (15, 20, 25 and 30 degres C), in light or dark, on top or between wet filter papers, and keeping or removing the seed coat, were determined respectively using petri dish method. At the same time germination trends were observed. RESULTS: The thousand seed weight was 33.24 g, and the seed water-absorbing reached saturation pot after soaking for 30 h. Higher germination rates were respectively recorded at 25 degrees C, between filter papers, and in dark after 24 h soaking in the pretreatment solution. CONCLUSION: The optimal condition for the germination of the seed of wild Disporum cantoniense is as follow: keeping testa, seed soaking for 24 h in seed germination agent and being incubated between wet filter papers in dark at 25 degrees C.

[Species diversity and host of Thesium chinense community].

OBJECTIVE: To study species diversity and the host of Thesium chinense community. METHOD: The investigation on phytocoenology was carried out on the T. chinense community in 7 areas of Anhui Province and Jiangsu Province. The correlation between species diversity of community and T. chinense abundance was analyzed regarding to the abundance of species, the abundant index of species, species diversity index and community even index. RESULT AND CONCLUSION: The results showed that T. chinense liked light, warm climate, liked acidic to neuter soil. The majority of T. chinense distributed in the humid wasteland and herbaceous community. There was a positive correlation between the abundance of T. chinense and the unity numbers of community, and a negative correlation between the abundance of T. chinense and the abundance, coverage, diversity index, Pielou even index of community. T. chinense host species was various. This investigation found 28 host species belong to 11 Families, among them 5 Families and 18 species were found for the first time.

[Study on quality of medicinal material of Thesium chinense].

OBJECTIVE: To study the quality of medicinal material of Thesium chinense. METHOD: The active ingredients of total flavonoids, kaempferol, mannitol, polysaccharides were selected as the evaluative indicators to comprehensively evaluate the quality of medicinal material of T. chinense. RESULT: The total flavone 3.38%, kaempferol 0.984 7 mg x g(-1), mannitol 6.12%, polysaccharides 14.08% and water soluble extract 30.28% were measured in the sample of T. chinense. There was a certain correlation among these selected active ingredients. The compositions of most biological activities component in T. chinense of different populations were similar, but the contents were different significantly. The content of activities component in T. chinense showed a general tendency of declining during growth period and with the increase time of storage. CONCLUSION: Flavone, kaempferol, mannitol, polysaccharides should be selected as the indicators to evaluate the quality of medicinal material of T. chinense.

[Determination and principal components analyze of mineral elements in different population of Thesium chinense].

OBJECTIVE: To determine the concentration of mineral elements and analyze the principal components in Thesium chinense. METHOD: Mineral elements were determined by ICP-DES. Principal components analysis (PCA) was used toanalyze and evaluate the characteristic elements. RESULT: T. chinense contained more than 17 mineral elements, Fe, Zn, Cu, Mn, Cr, Co, Ni, Sr, B, Ca, P, K, Na, Mg, Mg, Mn, Zn and Cu were abundance in T. chinense. The concentration of Mn and Zn were about 100 microg x g(-1), Mg was from 1 898.0 to 3 137.73 micro x g(-1), Fe > 500 microg x g(-1). PCA concluded that four factors (F1, F2, F3, F4 ) could be used to evaluate the quality of T. chinense. The function is following: F = 0.444 77F1 + 0.237 71F2 + 0.167 28F3 + 0.150 24F4. The scores of different populations of T. chinens were from 0.627 to 0.189. Zn,Cu,Mg,P, K, Al, Fe, Cr, Na, Co, Pb, Mn, B and Ca were the characteristic elements of T. chinense. CONCLUSION: T. chinense contain more than 17 mineral elements. Zn, Cu, Mg, P, K, Al, Fe, Cr, Na, Co, Pb, Mn, B and Ca were the characteristic elements of T. chinense.

[Study on endogenesis inhibitory substances in seed of Thesium chinense].

OBJECTIVE: To investigate the activity and the location of the endogenesis inhibitory substances in seed of of Thesium chinense. METHOD: The rough extracts from different concentrations, places and extracting times of T. chinense seeds were prepared and determined by its effect on wheat and Brassica sp seed. RESULT AND CONCLUSION: The extract dramatically inhibited the germentation and the growth of wheat and Brassica sp seed and the inhibitory activity was positively related to the concentration of the extracts. When the concentration reached 0. 32 g mL(-1), wheat seed did not germentate. With increasing the extracting times, the inhibitory activity first decreased, then increased. The capsule and kernel both had inhibitory substances and the latter was stronger than the former. Highly active inhibitory substances were found first time in the seed of T. chinense.