Effects of different water management options and fertilizer supply on photosynthesis, fluorescence parameters and water use efficiency of Prunella vulgaris seedlings.

BACKGROUND: Prunella vulgaris L. is a medical plant cultivated in sloping, sun-shaded areas in China. Recently, owing to air-environmental stress, especially drought stress strongly inhibits plant growth and development, the appropriate fertilizer supply can alleviate these effects. However, these is little information about their effects on P. vulgaris growing in arid and semi-arid areas with limited water and fertilizer supply. RESULTS: In this study, water stress decreased the photosynthetic pigment contents, inhibited photosynthetic efficiency, induced photodamage in photosystem 2 (PS2), and decreased leaf instantaneous WUE (WUEi). The decreased net photosynthetic rate (Pn) under medium drought stress compared with the control might result from stomatal limitations. However, fertilizer supply improved photosynthetic capacity by increasing the photosynthetic pigment contents and enhancing photosynthetic efficiency under water deficit. Moreover, medium fertilization also increased WUEi under the two water conditions, but fertilizer supply did little to alleviate the PS2 photodamage caused by drought stress. Hence, drought stress was the primary limitation in the photosynthetic process of P. vulgaris seedlings, while the photosynthetic characteristics of the seedlings exhibited positive responses to fertilizer supply. CONCLUSIONS: Appropriate fertilizer supply is recommended to improve photosynthetic efficiency, enhance WUEi and alleviate photodamage under drought stress.

Effects of ammonium to nitrate ratio on growth, nitrogen metabolism, photosynthetic efficiency and bioactive phytochemical production of Prunella vulgaris.

CONTEXT: Prunella vulgaris L (Labiatae) is commonly used as a traditional medicinal herb in some Asian and Europe countries. To date, few studies have been conducted to determine the influence of [Formula: see text] - N/[Formula: see text] - N ratio on growth, physiological development, and bioactive phytochemical accumulation in hydroponically grown P. vulgaris. OBJECTIVE: The current study was conducted to evaluate the effect of five [Formula: see text] - N/[Formula: see text] - N ratios on growth, nitrogen metabolism, photosynthetic efficiency, and bioactive phytochemical production in P. vulgaris. MATERIALS AND METHODS: Hydroponically cultivated P. vulgaris were fertilized with five [Formula: see text] - N/[Formula: see text] - N ratios in a greenhouse for 85 d. Dried weight of root, stem, leaf and spica, leaf area, photosynthetic efficiency, activities of nitrate reductase (NR), glutamine synthetase (GS), and the concentrations of N, soluble protein, and free amino acids in the leaves, as well as the contents of rosmarinic acid (RA), ursolic acid (UA), and oleanolic acid (OA) in the spicas were measured. RESULTS: Both [Formula: see text] - N and [Formula: see text] - N as the sole source of nitrogen had inhibitory effects on P. vulgaris growth. P. vulgaris fertilized with the 25/75 ([Formula: see text] - N/NO3 - N) ratio had the highest leaf area, photosynthetic rate, and chlorophyll content. The 25/75 ([Formula: see text]/[Formula: see text]) ratio increased the spica biomass by 1828%, nitrate-reductase (NR) activity by 98%, and soluble protein concentration by 29.45% compared with the 100/0 ([Formula: see text]/[Formula: see text]) treatment. Additionally, 25 [Formula: see text] - N/75 NO3 - N resulted in the highest contents of RA and total flavonoids as well as relatively high contents of UA and OA; therefore, this ratio had the highest yield of RA, UA, OA, and total flavonoids in spicas. DISCUSSION AND CONCLUSION: The use of 25 [Formula: see text] - N/75 [Formula: see text] - N is recommended to improve biomass production and medicinal quality of P. vulgaris.

Biochar mitigates negative effects of salt additions on two herbaceous plant species.

Addition of pyrolyzed biomass ("biochar") to soils has commonly been shown to increase crop yields and alleviate plant stresses associated with drought and exposure to toxic materials. Here we investigate the ability of biochar (at two dosages: 5 and 50 t ha(-1)) to mitigate salt-induced stress, simulating road salt additions in a factorial glasshouse experiment involving the broadleaved herbaceous plants Abutilon theophrasti and Prunella vulgaris. Salt additions of 30 g m(-2) NaCl to unamended soils resulted in high mortality rates for both species. Biochar (Fagus grandifolia sawdust pyrolyzed at 378 °C), when applied at 50 t ha(-1) as a top dressing, completely alleviated salt-induced mortality in A. theophrasti and prolonged survival of P. vulgaris. Surviving A. theophrasti plants that received both 50 t ha(-1) biochar and salt addition treatments showed growth rates and physiological performance similar to plants without salt addition. Biochar treatments alone also substantially increased biomass of P. vulgaris, with a ∼50% increase relative to untreated controls at both biochar dosages. Biochar did not significantly affect photosynthetic carbon gain (Amax), water use efficiency, or chlorophyll fluorescence (Fv/Fm) in either species. Our results indicate that biochar can ameliorate salt stress effects on plants through salt sorption, suggesting novel applications of biochar to mitigate effects of salinization in agricultural, urban, and contaminated soils.

[Preliminary study on breeding system of Prunella vulgaris].

The research was conducted to study the breeding system of Prunella vulgaris L. Flowering dynamics was observed. Pollen viability, stigma receptivity, pollen-ovule ratio (P/O), out-crossing index (OCI) were measured. Bagging experiments were conducted. The results showed that the life span of one single flower was 1-2 days, the flowering span for the inflorescence of stalk was 7-14 days, the P/O was 1 046+/-148. 26, the OCI was 2. Combined with results of bagging experiment, the breeding system of P. vulgaris L. was mixed with cross-polination and self pollination. In the absence of pollination insects, the pollination and fertilization can be accomplished with high seed setting rate, and the seeds have a relatively high germination rate.

[Factor of Prunella vulgaris yield components and morphological characteristics of relationship in different populations].

Prunella vulgaris is a perennial herb whose dry spike is used for medicine in China. It is also a very important traditional medicine. Current study was conducted to the biomass components factors of P. vulgaris in the different ecological environments for the development and protection. The results showed that the contribution factor of the production in different environments was significant differences. In favorable environment, the length of leaf, numbers of leaves, height, reproductive branch number of individuals gave the greatest contribution. In transitional habitats, the diameter of stem and spike, the length of leaf contributed the most. While in the undergrowth and dry hillside, the length of root, the width of leaf, the length of spike were the main factors for biomass.

Changes in bioactive components related to the harvest time from the spicas of Prunella vulgaris.

CONTEXT: Prunella vulgaris L. (Labiatae) is a perennial plant common in China and Europe and is rich in rosmarinic acid (RA), ursolic acid (UA), and oleanolic acid (OA). The dried spica of P. vulgaris has been used as traditional medicine in China for over a hundred years. To our best knowledge, no study has been conducted to determine the influence of harvesting time on concentrations of bioactive compounds of P. vulgaris. OBJECTIVE: In the current study, changes in the bioactive compounds present in spicas were investigated at five harvest times over 2 months. MATERIALS AND METHODS: Plant material were collected at five fixed dates: 5th May, 20th May, 7th June, 15th June, and 25th June and assayed for chemical contents by high-performance liquid chromatography (HPLC). RESULTS: Among the different harvest times, the highest levels of RA (56.81 mg·g⁻¹), UA (2.77 mg·g⁻¹), and OA (0.91 mg·g⁻¹) were found on 5th May, whereas the lowest levels of RA (1.66 mg·g⁻¹), UA (2.27 mg·g⁻¹), and OA (0.43 mg·g⁻¹) were observed on 25th June. DISCUSSION AND CONCLUSION: As each medicinal product has its own content requirement for different bioactive components, the optimum harvest time might be determined according to the accumulation dynamics of target compound in dried spicas of P. vulgaris. These results may be useful for determining the optimal harvest time when bioactive components are at the maximum level, which is in early May.

[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 content and distribution characteristics of mineral elements from cultivated and wild Prunella vulgaris].

OBJECTIVE: The contents of mineral elements in soil and each organ from cultivated and wild Prunella vulgaris were determined in order to provide a theoretical basis for exploitation and protection of wild resources and GAP study. METHOD: The contents of mineral elements (P, K, Ca, Mg, Na, Fe, Cu, Zn, Mn, Al) in soil and each organ from cultivated and wild P. vulgaris were determined by ICP-AES, and the results were analyzed by correlation analysis. RESULT: The contents of mineral elements in soil and different organs of P. vulgaris were significant different between cultivated and wild species; the contents of P and Cu ranked in the order of spica > leaf > stem, the order of Mg, Ca, Zn, Fe, Mn, Al from high to low was leaf > spica > stem, the concentrations of K, Na were mainly distributed in leaf and stem, less in spica. A distinctly positive correlation between soil and spica for Fe content, and the relationship between soil and leaf, stem were significant positive correlation, the concentrations of Zn in spica, leaf, stem were positively related to soil, K contents in soil and stem were significant positive correlation. The different organs of cultivated and wild P. vulgaris had a strong tendency to accumulate P. CONCLUSION: There was no direct relationship between the concentrations of mineral elements in P. vulgaris, and their corresponding soil P. vulgaris adjusts the concentration of mineral elements mainly by active absorption.

[Absorption and allocation of nitrogen, phosphorus, potassium in Prunella vulgaris and their relationship to dry matter accumulation].

OBJECTIVE: The accumulation of dry matter, nitrogen, phosphorus and potassium in Prunella vulgaris and their relationships under field condition were studied, in order to provide a basis for the rational fertilization. METHOD: Through the dynamic sampling of P. vulgaris in different growing stages, and the dry weight of plant, the amount of dry matter and the content of N, P and K within each organ of the plant were measured. RESULT: The dry weight of P. vulgaris linearly increased with the increase of nitrogen, phosphorus and potassium accumulation, there existed a significant correlation at whole growth period. The maximum stage accumulation rate of dry matter from mid-April to the beginning of May, reached 63.71%. The amount of dry matter was mainly distribution in leaves from late March to mid-April. The distribution ratio in stem was the highest from beginning of May to late May. Until mid-June, the distribution ratio of dry matter in spicas was higher than that in other organs. The absorption amounts of N, P and K were lower before mid-April, and the nutrient element was concentrated in plant leaves. From late April to beginning of May, the N, P and K accumulation reached maximum of total absorptive capacity, which accounted for 72.35%, 59.82%, 87.41%, respectively, and the mineral elements were concentrated distribution of plant stems. When transferred to reproductive stage, both accumulation amount and distribution rate of nutrient elements in spicas increased rapidly, which reached the maximum until mid-June. From elongation stages to quaring period was the period of maximal accumulation of dry matter and showed the maximal efficiency of N, P and K nutrition. CONCLUSION: The time from elongation stages to quaring period is the most crucial period in the growth development stage of P. vulgaris, and should be paid more attention to the supply of mineral nutrition and moisture of plant to promote spicas formation and dry matter accumulation in this stage. The average N, P2O5 and K2O absorption amount per 100 kg dry matter of spicas were 1.62, 0.36, 2.88 kg respectively, and the ratio of N-P2O5,-K2O was 1 : 0.22: 1.77.

[Textual research on original plant and dietotherapy history of Prunella vulgaris].

OBJECTIVE: To investigate the original plant and dietotherapy history of Prunella vulgaris by textual researches, and provide a theoretical basis for clinical medication, exploitation and protection of wild resources. METHOD: The ancient literatures in the graphic, geographical distribution and morphological description of P. vulgaris were used in this studied. RESULT: The varieties of P. vulgaris for therapeutic were no confusion. However, there has existed confusion between P. vulgaris and its confusable species (Ajuga ciliate, A. decumbens and Lagopsis supina) with appellations, morphological description and attached drawing of original plant. CONCLUSION: The original plant is originated from two species (P. vulgaris, P. asiatica). P. hispida was used as a certified medicinal material in Yunnan province from Ming Dynasty to modern time. The dietotherapy history of P. vulgaris in China can be traced back to Ming Dynasty or before.

[Effects of light intensity on photosynthetic characteristics and seedling growth of Prunella vulgaris].

OBJECTIVE: To study the effect of light intensity on photosynthetic characteristics and seedling growth of Prunella vulgaris under different light intensity. METHOD: The seedling of P. vulgaris was shaded with shading net, and relative parameters were measured. The data was statistically processed. RESULT: With the reducing light intensity, the young plant stems became slender, the leaf long increased. The plant height and net growth under 42% full light condition were significantly higher than those under the other light intensity, chlorophy II and carotenoid contents increased, as well as Chl a/b decreased under low light. Photosynthetic indicators of P(n), T(r) decreased under low light, but CO2 concentration increased, and G(s) content decreases and then increased under 10% full light intensity. CONCLUSION: P. vulgaris manifested the different plasticity and adaptability under different light intensities. The 42% light intensity was the best and the proper shading would promote the growth of seedlings.

[Effect of optimized fertilization on spicas biomass and yield of Prunella vulgaris].

OBJECTIVE: To study the effects of nitrogen (N), phosphorus (P2O5), potassium (K2O) and organic compound fertilizer (OF) on spicas biomass and yield of Prunella vulgaris in order to provide a theoretical basis for good agriculture practice (GAP). METHOD: Field plot experiments with a 4-variable quadratic orthogonal rotation combination design were adopted, and a function model of spicas yield in P. vulgaris was established. RESULT: The model analysis showed that spicas yields of P. vulgaris were significantly influenced under the N, P2O5 and K2O applications, among there factors, N had the greatest effects on spicas yield of P. vulgaris, the next was P2O5 and K2O, OF had the smallest effects on spicas yield. At the lower fertility levels, the spicas yields of P. vulgaris were improved along with the increasing of N, P2O5, K2O and OF applications, but the spicas yields decreased when N, P2O5, K2O and OF were applied too much. CONCLUSION: In this experiment condition, the spicas yields of P. vulgaris could reach to 722 kg x hm(-2) when the fertilizer rates were N 303. 9-335.1 kg x hm(-2), P2O5 432.5-500.6 kg x hm(-2), K2O 206.6-240.2 kg x hm(-2), OF 2 312.5-2 687.5 kg x hm(-2).

[Influence of nitrogen forms ratio on growth and photosynthetic characteristics in Prunella vulgaris].

OBJECTIVE: The effects of different nitrogen forms on the growth and photosynthetic characteristics of Prunella vulgaris were observed. METHOD: Water culture experiments were carried out to observe the effects of NH4+: NO3- ratios(100:0, 75: 25, 50:50, 25:75, 0:100 in mmol x L(-1)) on the growth and photosynthetic characteristics of P. vulgaris. RESULT: The leaf area, fresh biomass and P(n) of these cultivars increased with the increasing of NH4(+) -N: NO3(-) -N ratios, and they were found to be the highest in 25: 75 NH4(+) -N: NO3)-) -N. However, they decreased with the increasing NH4(+) -N: NO3(-) -N ratio further. P. vulgaris had a minimum leaf area, biomass, chlorophyll content and P(n) in pure ammonium group. The biggest chlorophyll and carotenoid contents were found in the ratios of NH4(+) -N to NO3(-) -N of 50: 50. CONCLUSION: The results indicated that properly increasing nitrate proportion could promote the growth and photosynthesis of P. vulgaris.

Testing spatial theories of plant coexistence: no consistent differences in intra- and interspecific interaction distances.

Plants stand still and interact with their immediate neighbors. Theory has shown that the distances over which these interactions occur may have important consequences for population and community dynamics. In particular, if intraspecific competition occurs over longer distances than interspecific competition (heteromyopia), coexistence can be promoted. We examined how intraspecific and interspecific competition scales with neighbor distance in a target-neighbor greenhouse competition experiment. Individuals from co-occurring forbs from calcareous grasslands were grown in isolation and with single conspecific or heterospecific neighbors at distances of 5, 10, or 15 cm (Plantago lanceolata vs. Plantago media and Hieracium pilosella vs. Prunella grandiflora). Neighbor effects were strong and declined with distance. Interaction distances varied greatly within and between species, but we found no evidence for heteromyopia. Instead, neighbor identity effects were mostly explained by relative size differences between target and neighbor. We found a complex interaction between final neighbor size and identity such that neighbor identity may become important only as the neighbor becomes very large compared with the target individual. Our results suggest that species-specific size differences between neighboring individuals determine both the strength of competitive interactions and the distance over which these interactions occur.

[Effect of different water treatments on quality and yield of spadix in Prunella vulgaris].

OBJECTIVE: Prunalla vulgaris was used as the experimental material to study the effects of water stress on the related quality charaters of spadix in P. vulgaris. METHOD: By weighting method to experiment the relative characteristics in vegetative period and reproductive period respectively were studied under timing and quantitative water stress conditions everyday with the method of statistics to compared, including biological characteristics and content of ursolic acid and oleanolic acid. RESULT AND CONCLUSION: It is true that the better water range of growth in vegetative period of P. vulgaris is 80% -85%; The 65%-70% field leakage coefficient maximum was the best and the proper water range which would promote the growth, but the best range of active component is 80% -85%.

Biosynthesis of antioxidative enzymes and polyphenolics content in calli cultures of Prunella vulgaris L. in response to auxins and cytokinins.

Prunella vulgaris L. is one of the therapeutic herbs containing various polyphenolics, which is used for multiple medicinal purposes. In this study, plant growth regulators (PGRs)-induced calli cultures from seed-derived leaf explants were exploited for the production of stress enzymes and polyphenolics. A growth curve was plotted for each PGR for 49 days period, which showed a distinct lag, log and decline phases. Here, the combination of naphthalene acetic acid (NAA) and 6-benzyleadenine (BA; 0.5 and 2.0 mg l-1) produced maximum fresh (6.32 FW-g/100 ml) and dry biomass (0.75 DW-g/100 ml) in contrast to control. The maximum synthesis of SOD (0.0154 FW-nM/min/mg) was detected on media comprising mixture of NAA and BA (1.5 mg l-1), while POD enzyme (0.366 FW-nM/min/mg) was higher at 0.5 mg l-1 NAA and 2, 4-dichlorophenoxy acetic acid. Further, NAA and BA (1.5 and 2.0 mg l-1) boosted up the synthesis of phenolics (18.83 GAE-mg/g-DW) and flavonoids content (18.05 RE-mg/g-DW) than control. Moreover, NAA of 1.0 and 2.0 mg l-1 were found supportive for maximum antioxidant activity (87.4%) and total protein (716 µg BSAE/mg-DW). This study will contribute in the development of cell culture in fermenter and synthesis of antioxidant secondary metabolites for commercial uses.

[Effect of water stress on physiological and growth charaters of Prunella vulgaris at the vegetative stage].

OBJECTIVE: To study the effect of water stress on physiological and the growth characters of Prunella vulgaris at the vegetative stage. METHOD: The plants were treated timely and quantitatively by weighting method, and the relevant index were measured under different water stress conditions. RESULT: With the long time of water stress, the plants of SY2 and SY3 showed the quickest growth rate and the best of growth vigor. The protective enzyme and osmoregulation substance presented the trend of increase firstly and then decrease. Under the same time of water stress, with the increase of extent in treatment, the protective enzyme and osmoregulation substance presented the trend of increase firstly and then decrease, and SY2 and SY3 were the lowest. CONCLUSION: The protective enzyme and osmoregulation substance of P. vulgaris have a whole effect. The suitable water range of growth in P. vulgaris is 65%-80%.

[Genetic variation, correlation and principle component analysis on morphological characteristics of various germplasm from Prunella vulgaris].

OBJECTIVE: To study the correlation among the morphological characteristics and the spica yield of various germplasm of Prunella vulgaris. METHOD: The various P. vulgaris germplasm from all over the country were investigated by analysis of correlation analysis, path analysis and principle component analysis in a randomized block experiment. RESULT: The 6 morphological characteristics were greatly different from each other in various germplasm. The spica yield per plant had a very significantly positive correlation with the number of spica per plant and fresh leaves weight per plant, meanwhile the correlation between the spica yield per plant and spica length was very significantly. Three principal components which accounted for 87.533% of total variance were extracted from the principal component analysis. CONCLUSION: The strong growth potential, the number of spica per plant and spica length were main factors for the selection of high yield breeding of P. vulgaris.

iTRAQ-based quantitative proteomic analysis of salt stress in Spica Prunellae.

Spica Prunellae is an important Chinese herbal medicine. Because of its good curative effect on various diseases, this herb is consumed in large quantities in clinical applications. The metabolites of Spica Prunellae are known to change under salt stress; however, the difference in protein levels of Spica Prunellae between saline and normal conditions is unclear. In this study, we used proteomics techniques to identify differentially expressed proteins in Spica Prunellae under different saline conditions. (iTRAQ) MS/MS was used to detect statistically significant changes in protein between salt stress and normal conditions. Ultimately, we detected 1,937 proteins, 89 of which were detected in two different comparison. Based on GO, STRING and KEGG analyses, 35 significantly differentially expressed proteins were selected for further analysis. The results of functional and signal pathway analyses indicated that the cellular protein and carbohydrate metabolism of Spica Prunellae was weaker, calcium ion transport was higher, photosynthesis was higher, and protein production was faster under saline conditions than under normal conditions. This study provides useful information for studying the causes of differences in secondary metabolites in Spica Prunellae under salt stress and the protein mechanisms related to their quality.

[Studies on germination characteristics of Prunella vulgaris seeds].

OBJECTIVE: To understand the effect of illumination, temperature on the germination of the Prunella vulgaris seeds. METHOD: The general germination method. RESULT: Illumination showed no clearly effect on the germination rate of the P. vulgaris seeds under proper temperature condition; However, illumination was the main factor to determine the germination rate of the P. vulgaris seeds when the temperature condition was unsuitable. The germination rate of the P. vulgaris seeds decreased with the time and increased when the marinating time was from 12 to 36 hours. When temperature reached 5-25 9 degrees C, the trend of the germination rate increased at frst and then decreased. CONCLUSION: The optimal germination condition of P. vulgaris seeds is 12 h of marinating time at the temperature of 20 degrees C under illumination.