ABSTRACT
Ginsenosides are the main active ingredient and allelochemicals of Panax ginseng, and they play an important role in ginseng growth and in ecological adaptation. To study the influence of ginsenosides on soil microbial communities, the method of given exogenous total ginsenosides of different concentrations were used to study the influence of ginsenosides on new forest soil microbial community, evaluate the change of metabolic activity of microbial community and investigate the ecological effect of ginsenosides on soil microbial community. Results showed that, exogenous total ginsenosides promoted metabolic activity of microbial community in new forest soil at different concentrations compared with the control after 10 d and 40 d treatment. After 10 d,except for the Evenness index, all of the other indices indicated that the functional diversity of the soil microbial community in the new forest firstly increased then decreased with increase of the total ginsenosides concentration. The Substrate richness for 0.01 g•L⁻¹ soil treatment was significantly different from that of the control. After 20 d, 30 d and 40 d, except for the Evenness index, all of the other indices indicated that the functional diversity of the soil microbial community in the new forest increased with total ginsenosides. These results suggested that ginsenosids can change soil microbial community and microbial metabolic activity, which alter soil microbial ecology and accordingly affect the growth of ginseng with accumulation of ginsenosides in the soil.
ABSTRACT
Plate assay and spore germination method were used to study the chemotaxis response of Alternaria panax to arginine, glutamic acid, aspartic acid and threonine. The result showed that the optimum temperature of A. panax chemotaxis response to four amino acids were all 25 ℃. And chemotaxis responses of A. panax were different under conditions of different concentration and pH value. The chemotaxin reached to the highest under the condition of 2 mg•L⁻¹ and pH value was 7 for arginine, glutamic acid and threonine while 20 mg•L⁻¹ and pH value was 6 for aspartic acid . The data of chemotactic migration index (CMI) were 1.24, 1.38, 1.27, 1.31 and chemotactic growth rates(CGR) were 0.451 0, 0.353 0, 0.381 3, 0.228 8 and spores germination rates(SGR) were 57.33%，63%，56.67%，58% and the dry weight of mycelial (DWM) were 372.9, 348.5, 314.4, 390.2 mg•L⁻¹ respectively. It indicated that the low and middle concentration of amino acid had significant promoting effect on chemotaxis response of A. panax. As important substances generated in ginseng root, amino acids exhibited an efficient chemotactic effect on A. panax, and some even show inhibition effect under high concentration.
ABSTRACT
The chemotaxis response of Erwinia carotovora to different sugars and amino acids in four kinds of chemotactic parameters (concentration, time, temperature and pH ) was determined by capillary method. The results showed that when pH was 8, concentration was 0.025 mg•L ⁻¹, culture temperature was 25 ℃ and the duration was 60 minutes, the optimal chemotaxis rate of lysine was 2.509,when pH was 6, concentration was 0.25 mg•L ⁻¹, culture temperature was 25 ℃ and the duration was 60 minutes, the optimal chemotaxis rate of arginine was 2.218 8,when pH was 7, concentration was 0.25 mg•L ⁻¹, culture temperature was 30 ℃ and the duration was 60 minutes, the optimal chemotaxis rate of L-rhamnose was 3.091 2, when pH was 6, concentration was 0.25 mg•L ⁻¹, culture temperature was 30 ℃ and the duration was 45 minutes, the optimal chemotaxis rate of D-arabinose was 3.026 3. Sugars and amino acids had obvious chemotaxis with E. carotovora,the high concentration of carbohydrate and amino acid exited an inhibitory effect on chemotaxis response of E. carotovora, and the chemotaxis response decreased with the increase of concentration of carbohydrates and amino acids.
ABSTRACT
This paper is in order to study the anti-feeding and growth inhibition activity of toatal ginsenoside of ginseng stems and leaves against 4th-instar Mythimna separata larvae. Simulating natural growing condition indoors, on the base, To study the anti-feeding and growth inhibition activity of toatal ginsenoside against 4th-instar M. separata larvae by leaf disc test. The toatal ginsenoside appeared to be of significant antifeeding activity against 4th-instar M. separata larvae. The 4th-instar M. separata larvae fed on the leaves of Sorghum bicolor treated with 20, 10, 5 g · L(-1) toatal ginsenoside. At 8 h, non-selective anti-feeding rate were 88.67%, 64.40% and 47.36%, and selective anti-feeding rate were 62.49% , 44.29% and 34.19%; Compared with the photographic, The toatal ginsenoside conld make the development period had prolonged 13h in treated group. The toatal ginsenoside had significant inhibition effect on feeding and growth and development against 4th-instar M. separata larvae, and inhibition effect increases as the increase of concentration ginsenoside.
Subject(s)
Animals , Ginsenosides , Pharmacology , Insecticides , Pharmacology , Larva , Moths , Panax , ChemistryABSTRACT
In this paper, three kinds of chemotactic parameters (concentration, temperature and pH) were determined by plate assay and spore germination method to research the chemotactic response of Botrytis cinerea and Alternaria panax, and their spores on total ginsenosides. The results showed that Botrytis cinerea had strong chemotactic response at the mid-concentration of total ginsenosides (cultivation temperature was 20 degrees C and pH value was 6), and the data of chemotactic migration index (CMI) was 1.293 0, chemotactic growth rate (CGR) was 0.476 0, spore germination rate (SGR) was 53%, and dry weight of mycelial (DWM) was 0.452 6 g x L(-1); however, Alternaria panax had strong chemotactic response at the low-concentration of total ginsenosides (cultivation temperature was 25 degrees C and pH value was 6), and the data of chemotactic migration index (CMI) was 1.235 4, chemotactic growth rate (CGR) was 0.537 0, spore germination rate (SGR) was 67%, and dry weight of mycelial (DWM) was 0.494 8 g x L(-1). The results indicated that the low and middle concentration (2, 20 mg x L(-1)) of total ginsenosides had significant promoting effect on chemotactic response of these two pathogens, and the spore germination, mycelial growth rate, dry weight of mycelial of them were also significantly improved by this chemotactic response, whereas it decreased as the increase of total ginsenosides concentration.
Subject(s)
Alternaria , Physiology , Botrytis , Physiology , Chemotaxis , Drugs, Chinese Herbal , Metabolism , Pharmacology , Ginsenosides , Metabolism , Pharmacology , Panax , Metabolism , Microbiology , Plant Diseases , Microbiology , Spores, Fungal , PhysiologyABSTRACT
<p><b>OBJECTIVE</b>To study the anti-feeding effect of total ginsenoside of ginseng stems and leaves on Heliothis dipsacea larvae.</p><p><b>METHOD</b>The natural growing condition for lavae was simulated indoors. The anti-feeding effect of total ginsenoside on Heliothis dipsacea larvae was studied by leaf disc test.</p><p><b>RESULT</b>The total ginsenoside appeared showed a significant antifeeding effect. The Heliothis dipsacea larvae fed with the leaves of soybean treated with 2.0%, 1.0% and 0.5% total ginsenoside, respectively. At 8 h, non-selective anti-feeding rate were 93.40%, 83.42% and 75.19%, and selective anti-feeding rate were 77.53% , 73.58% and 58.86%.</p><p><b>CONCLUSION</b>The toatal ginsenoside had significant inhibition effect on Heliothis dipsacea larvae, and inhibition effect increases as the increase of concentration ginsenoside.</p>