Induction of Resistance of Antagonistic Bacterium Burkholderia contaminans to Postharvest Botrytis cinerea in Rosa vinifera.

In order to study the problem that grapes are vulnerable to microbial infection and decay during storage, a method based on antagonistic Burkholderia contaminans against postharvest Botrytis cinerea of Rosa vinifera was proposed in this paper. The method tested the resistance induction mechanism of Botrytis cinerea after harvest and determined the fruit decay rate treated by antagonistic Burkholderia contaminans. The results showed that the antagonistic bacterium B-1 had bacteriostatic effect on many common pathogens of fruits and vegetables to a certain extent, and the bacteriostatic range was wide. Among them, the inhibition rate of Fusarium moniliforme was 75.5% and that of Botrytis cinerea was 51.2%. After testing, it can be found that antagonistic bacteria have an inhibitory effect on pathogenic fungi and have an effect on phenylpropane metabolic pathway, reactive oxygen species metabolic pathway, and the activities of other resistance-related enzymes. Through comparison, it can be found that the antagonistic Burkholderia contaminans has a strong antibacterial mechanism against Botrytis cinerea of rose grape after harvest. The fruit treated with antagonistic B Burkholderia B-1 has significantly reduced the decay rate and increased the activity of antibacterial active protein.

Study on the occurrence law and green control of grape gray mold from the perspective of ecological balance.

With the increase of grape planting years, the base number of pathogenic seedlings and insect population is gradually rising. In addition, the introduction, breeding system and control of seedlings are not standardized and other human factors, the occurrence of Botrytis cinerea(B.cinerea) on grape is becoming more and more serious, resulting in a prominent problem of yield decline. In this paper, the occurrence of B.cinerea was monitored and its control effect was tested from the perspective of ecological balance. Finally, the biological characteristics and control of B.cinerea were studied. The spore catcher was used to catch the pathogen spores of B. cinerea, and the amount of sporangium scattering reached its peak from August to September Spore scattering is affected by meteorological factors, and the temperature has reached a very significant level, and the low temperature and high humidity conditions are conducive to the disease; The results showed that the resistance frequency of 304 B.cinereastrains to carbendazim, boscalid, pyrimethanil was higher than 50%; the volatile compounds produced by yeast (Trichosproom sp.) YE-3-2 significantly inhibited the growth of B.cinerea (inhibition rate was 62.93%, according to the occurrence regularity of B.cinerea, the accurate and effective agricultural measures had a good control effect on B.cinerea, which could improve the quality of grape fruit and provide some help for the prevention of grape gray mold.

Identification and Predictions Regarding the Biosynthesis Pathway of Polyene Macrolides Produced by Streptomyces roseoflavus Men-myco-93-63.

A group of polyene macrolides mainly composed of two constituents was isolated from the fermentation broth of Streptomyces roseoflavus Men-myco-93-63, which was isolated from soil where potato scabs were repressed naturally. One of these macrolides was roflamycoin, which was first reported in 1968, and the other was a novel compound named Men-myco-A, which had one methylene unit more than roflamycoin. Together, they were designated RM. This group of antibiotics exhibited broad-spectrum antifungal activities in vitro against 17 plant-pathogenic fungi, with 50% effective concentrations (EC50) of 2.05 to 7.09 µg/ml and 90% effective concentrations (EC90) of 4.32 to 54.45 µg/ml, which indicates their potential use in plant disease control. Furthermore, their biosynthetic gene cluster was identified, and the associated biosynthetic assembly line was proposed based on a module and domain analysis of polyketide synthases (PKSs), supported by findings from gene inactivation experiments.IMPORTANCEStreptomyces roseoflavus Men-myco-93-63 is a biocontrol strain that has been studied in our laboratory for many years and exhibits a good inhibitory effect in many crop diseases. Therefore, the identification of antimicrobial metabolites is necessary and our main objective. In this work, chemical, bioinformatic, and molecular biological methods were combined to identify the structures and biosynthesis of the active metabolites. This work provides a new alternative agent for the biological control of plant diseases and is helpful for improving both the properties and yield of the antibiotics via genetic engineering.

Characterization of Botrytis cinerea Isolates From Grape Vineyards in China.

One hundred thirty-five single-spore isolates were collected from grape vineyards from 15 provinces or autonomous regions belonging to five viticulture climatic zones in China. All the isolates were identified as Botrytis cinerea based on their morphological and molecular characters. The 135 isolates were all heterothallic isolates. Seventy-one isolates belonged to the MAT1-1 type and 64 were characterized to MAT1-2 type. All the isolates studied belonged to Group II based on PCR-RFLP of the Bc-hch locus. The four TE genotypes, transposa, Boty-only, Flipper-only, and vacuma, comprised 51.9%, 33.3%, 10.4%, and 4.5%, respectively, of the total population. The frequency of transposa was highest in the total population and the most of any subpopulation (each viticulture climatic zone), and Boty-only was highest in warm areas (46.2%). Vacuma was mainly distributed in northern China, although in small amounts, and Flipper-only was mainly was distributed in humid tropical areas (42.9%). A microsatellite analysis of B. cinerea populations was performed to assess the genetic population structure. A total of 127 different MLGs were identified among 135 B. cinerea isolates, with a genotypic diversity of 0.9991. The transposa population isolates showed higher genetic diversity than other populations. Pairwise tests of genetic differentiation among four TE-type populations yielded generally low to high Gst values. All isolates belonged to two genetic clusters. The population microsatellite diversity and genetic structure had a certain correlation with the TE type and geographic origin. This is the first report of the genotypic diversity of B. cinerea isolates from grape vineyards across China.

[Construction of nsdAmgh gene disruption mutant in Strempomyces roseoflavus Men-myco-93-63].

Insertional mutagenesis is a widely used method to determine the function(s) of a gene. To study the function(s) of the gene nsdAmgh in Streptomyces roseoflavus, a homologous recombination vector pSRNA2500 was structured in this paper. The recombination donor vector was then transformed into Strempomyces roseoflavus strain Men-myco-93-63 by conjugative transfer. The transformants were subjected to selection under the pressure of high temperature and appropriate antibiotics. As a result, several disrupted mutants of nsdAmgh gene, with a phenotype of Am(s)Km(r), were isolated and verified using PCR and Dot-blotting and Southern blotting hybridization methods. Functional analysis showed that the disrupted mutants of nsdAmgh had a two-fold higher inhibition against Verticillium dahlia Kleb than that of the wild strain Men-myco-93-63, which all will provide a new study route for future research about positive and negative regulator in Men-myco-93-63.

[Study on over-weight, obesity and the exposure to stroke risk factors among 40 year olds and over in a community-based population].

OBJECTIVE: To describe the distribution of over weight and obesity to discover the level of exposure on risk factors of stroke among people aged 40 and over, in a community-based population. METHODS: From 2003 to 2004, people aged > or = 40 years in a community of Fengxian district in Shanghai were selected by cluster sampling. Out of 11,791 individuals who were selected, 10,565 met the inclusion criteria and responded to the investigation. By face to face interview, a cross-sectional survey was carried out, using a questionnaire for risk factors of stroke. Height, weight and blood pressures were measured and cerebrovascular hemodynamic parameters (CVHP) were checked. Age and gender distribution of over weight and obesity in the population were described. Using 60 year as cut-off point, participants were grouped into three: normal, over weight and obesity by body mass index. Level of stroke risk factor exposure between groups was compared and logistic regression model was used for multiple analyses. RESULTS: Proportions of over weight and obesity were 28.5 percent and 4.1 percent in male and 26.3 percent and 4.2 percent in female (P = 0.045). Systolic and diastolic blood pressure in over weight group were (132.5 +/- 19.4) mm Hg and (83.9 +/- 10.5) mm Hg (1 mm Hg = 0.133 kPa), which were higher than that in normal weight group and lower than that in obese group (P < 0.05). Exposure rate of heart disease, family history of stroke in < 60 year old group and diabetes in > or = 60 year group increased along with the increase of weight. Exposure rate of hypertension, abnormality of CVHP score in both age groups were also increased with the increase of weight. Data from multiple logistic regression indicated that hypertension, family history of stroke and heart disease, CVHP score below 75 points, sex and age were independent factors of over weight and obese. CONCLUSION: The prevalence of over weight or obesity in a community-based population among aged 40 years or over was around 30 percent. The overall exposure rate of stroke risk factors were increasing along with the increase of weight, especially for those in the middle age.

[Baseline study and analysis on a stroke risk factor-related cohort in Fengxian county of Shanghai].

OBJECTIVE: To explore the exposed level of stroke risk factors in Fengxian county of Shanghai and the relationships between risk factors and stroke. METHODS: Community based populations including 10,565 individuals aged 40 years old and over were cluster sampled from Fengxian county in 2003 or 2004. Status of exposure on common risk factors such as hypertension, cardiovascular disease, diabetes, family history of stroke, cigarette smoking, alcohol intake were gathered while cerebral vascular hemodynamic index (CVHI) was examined, with CVHI score below 75 points as abnormal. During 2003 to 2006, 78 stroke cases occurred. The relationships between risk factors and stroke were analyzed by univariate and Cox proportional hazards regression models. RESULTS: Rates of exposure regarding hypertension, cardiovascular disease, diabetes, family history of stroke, obesity (BMI > or = 28 kg/m2), smoking, drinking and CVHI score abnormal were 21.14%, 6.72%, 1.88%, 5.63%, 4.17%, 34.96%, 17.81% and 29.43%, respectively. Data from Univariate analysis indicated that relative risk (95% CI) of above-mentioned risk factors were 2.76 (1.76-4.32), 2.19 (1.16-4.14), 1.52 (0.38-6.19), 1.58 (0.69-3.62), 1.24 (0.45-3.38), 1.75 (1.12-2.73), 2.10 (1.30-3.39) and 12.72 (7.02-23.06), respectively. Results from Cox proportional hazards regression models analysis showed that cigarette smoking, CVHI score abnormal were screened into equation. CONCLUSION: Among all the risk factors, rate of hypertension was the highest while hypertension, cardiovascular disease, cigarette smoking, alcohol intake and abnomal CVHI score had remarkable etiological correlations to stroke. Abnormal CVHI score, cigarette smoking seemed to be the independent forecasting factors related to stroke.

[Effectiveness of Nao'an Capsule on stroke prevention among high risk population in Nanhui, Shanghai].

OBJECTIVE: To evaluate the effectiveness of stroke prevention among high risk population, using Nao'an Capsules. METHODS: Participants were selected from 696,558 residents in Nanhui, using county of Shanghai city. Individuals aged 35 years old and over with at least one risk factor exposure to stroke, received cerebral vascular hemodynamic examination. 18,271 cases meeting the criteria of cerebral vascular hemodynamic indexes accumulative score below 70 points were defined as individuals with high-risk and targets to receive intervention. According to the willingness of the participants, 10,313 cases received Nao'an Capsules for intensive intervention based on general intervention measures compared to 7958 cases only receiving general intervention. After the implementation of intervention, incidence and mortality rates of stroke and the effectiveness of three-year intervention were studied. RESULTS: Incidence of stroke in Nao'an Capsules group was significantly lower than that of the general intervention (P < 0.01) with 53.8% in males and 58.4% in females. The relative risk (RR) in two gender groups were 0.46 (0.33 - 0.64) and 0.39 (0.30 - 0.50) respectively. Multiple logistic regression analysis indicated that the history of hypertension, accumulative score of cerebral vascular hemodynamic indexes, age, gender and Nao'an Capsules intervention were the variables selected into the equation and significantly related to stroke. Among the variables, Nao'an Capsule was the strongest factor with a RR of 0.41. CONCLUSION: Incidence of stroke in Nao'an Capsule intervention group was significantly lower than that in the general intervention group after 3 years of intervention, suggesting that Nao'an Capsule intervention was the strongest factor affecting stroke occurrence in individuals at high-risk.

[The relationship between hypertension and cerebral hemodynamic scores of vascular function accumulative].

OBJECTIVE: To probe into the relationship between hypertension and hemodynamic score of cerebral vascular accumulative function by though studying the history of hypertension and level of blood pressure. METHODS: The database of blood pressure and cerebral vascular hemodynamic indexes (CVHI) were from baseline data and measurement in a cohort. 18,512 participants who met the included criteria were enlisted in the study. The function scores were estimated using uniform methods according to CVHI. Participants were grouped by age, years of having hypertension and level of blood pressure. Differences of the function score between different groups were compared. RESULTS: The function score in hypertension group was significantly lower than that of normal tension group, which decreased by 13.3 points. Within 5 years of hypertension history, the function score decreased as course of hypertension prolonged. The same trend was found between the score and level of both systolic and diastolic blood pressure. When systolic blood pressure elevated to 140 mmHg or diastolic blood pressure elevated to 95 mmHg, the function score was below 75 points. CONCLUSION: There were significant relationship between decrease of the function scores and medical history, course of hypertension as well as level of blood pressure.

[Distribution of cerebral vascular hemodynamic indexes].

OBJECTIVE: To describe the distribution of cerebral vascular hemodynamic indexes (CVHI). METHODS: A number of 25,355 age 35 and over were selected in the Northeast China by cluster sampling. CVHI were checked during baseline survey and were followed to see the occurrence of stroke. Distribution of CVHI among non-stroke population, individuals prior to the onset of stroke and patients with stroke were described. RESULTS: The CVHI accumulative score, V(mean), V(max) and V(min) were dramatically decreasing, but RV, Zcv, WV and DR were significantly increasing as age increased. V(max), RV and CP were significantly higher in males but WV was lower than that of females. The CVHI accumulative score, V(min) and RV were 95.0, 10.23 and 75.8 in non-stroke population, 51.25, 6.71 and 122.72 pre stroke group, and 55.0, 6.78 and 115.89 in patients with stroke respectively. There were significant differences among three groups after controlling of age and sex (P < 0.01). CONCLUSION: Variance of CVHI was closely related to age, and there appeared a significant abnormal of CVHI before and after stroke.

[A cohort study on cerebral vascular hemodynamics accumulative score and risks of stroke].

OBJECTIVE: To estimate relative risk (RR) of cerebral vascular hemodynamics indexes (CVHI) accumulative score as well as some other risk factors of stroke. METHODS: A cohort study was carried out in 25 355 participants aged 35 and over in Northeast of China from 1994 to 2001. In the baseline survey, exposure rates of hypertension, diabetes, family history of stroke and hypertension, etc. were collected and CVHI was examined. CVHI accumulative score was synthesized according to contribution of single index. During the 7-year following up, 228 stroke cases were identified and stroke coming on was defined as the endpoint of observation. Uni-variable and multiple variables analysis were carried out for estimating RR of CVHI and other risk factors of stroke. RESULTS: Uni-variables analysis indicated that RR (95% confidence interval, CI) of Hypertension, heart diseases, diabetes, family history of hypertension and stroke, overweight or obesity, alcohol intake, cigarette smoking and CVHI < 75 scores were 3.23 (2.48 - 4.20), 2.53 (1.92 - 3.33), 2.38 (1.55 - 3.64), 1.32 (1.02 - 1.72), 1.82 (1.37 - 2.41), 1.62 (1.25 - 2.11), 1.48 (1.07 - 2.04), 1.76 (1.34 - 2.31) and 7.30 (5.43 - 9.80) respectively. Cox regression analysis showed that CVHI below 75 points, family history of stroke, cigarette smoking, heart disease, hypertension, age and sex were the factors being selected in equation. There was a significant dosage response between the decrease of CVHI score and the increase of stroke risk. RR of stroke reached 12.55 when CVHI below 75 points and history of hypertension appeared in the same individuals. CONCLUSION: Abnormality of CVHI score seemed to be the most important and independent factor among stroke risk factors. Decrease of CVHI score might serve as a marker of high risk and play important role in stroke, especially coexistence with hypertension.

[Study on a test of screening to predict stroke-using cerebral vascular hemodynamic indexes].

OBJECTIVE: To evaluate efficacy and optimal cut-off-point through cerebral vascular hemodynamic indexes (CVHI) examination to predict stroke. METHODS: A number of 20,333 people at 35 years old and over were checked by CVHI and accumulative score was calculated according to the value of detected indexes. Risk factors of stroke were investigated simultaneously. One hundred and sixty-eight patients with stroke occurred during 4-year following up. Typical syndromes and signs stroke were used as golden standard to evaluate screening efficacy of CVHI. RESULTS: Score of optimal cut-off-point of cerebral vascular hemodynamic indexes was under 75 in ROC curve analyses. Sensitivity, specificity, accuracy, positive and negative predictive values, positive and negative likelihood ratios as well as Youden's index for predicting stroke within 4 years after examination were found to be 87.50%, 67.70%, 67.86%, 2.21%, 99.85%, 2.71, 0.18 and 0.55 respectively. Sensitivity and positive predict values for predicting cerebral vascular thrombosis were superior to predicting cerebral hemorrhage. Positive predicting value in risk exposure population was higher than that of overall population. Coefficiency of variation of cerebral vascular hemodynamic examination was 4.03%. The agreement rate of examination between two physicians was 97.62% and Kappa value was 0.94. CONCLUSION: The score of optimal cut-off-point of cerebral vascular hemodynamic indexes examination was 75. Both Efficacy and reliability for predicting stroke seemed to be good, especially for predicting cerebral vascular thrombosis.