Advanced Search

null null

Default Latest Most Read

For Selected View Abstracts Download Citations EndNote Reference Manager ProCite BibTeX RefWorks Toggle Thumbnails

Guidance: Biological Control of Diseases and Insect Pests is Valid Method to Ensure Vegetable Safe Producing     LEI Zhong-ren Scientia Agricultura Sinica   2016,49(15 ):2932 -2934. DOI:10.3864/j.issn.0578-1752.2016.15.007 Abstract  （372） HTML （6） PDF（pc） （248KB）（982） Save Reference丨 Related Articles丨 Metrics

Isolation and Identification of Lipopeptide Antibiotics Produced by Bacillus amyloliquefaciens B1619 and the Inhibition of the Lipopeptide Antibiotics to Fusarium oxysporum f. sp. lycopersici     XIANG Ya-ping, ZHOU Hua-fei, LIU Yong-feng, CHEN Zhi-yi Scientia Agricultura Sinica   2016,49(15 ):2935 -2944. DOI:10.3864/j.issn.0578-1752.2016.15.008 Abstract  （430） HTML （11） PDF（pc） （1324KB）（1010） Save 【Objective】 Bacillus amyloliquefaciens, biocontrol strain B1619, can effectively prevent and control the occurrence and damage of tomato fusarium wilt. In order to study and analyze theantifungal substancesproduced by strain B1619, the lipopeptide antibiotics were isolated from the supernatant of fermented broth.【Method】Three primers designed based on the known lipopeptide genes sfp, ituA and fenB were used to amplify the corresponding genes from the genome of B1619 strain. The crude lipopeptides extracts were extracted by acid precipitation and methanol. The supelcleanTM LC-18 column and PHASE HF-NH2 column were used to separate lipopeptide antibiotics. All the samples were analyzed by HPLC and MALDI-TOF-MS techniques. Inhibition rates of the three lipopeptide antibiotics against Fusarium oxysporum f. sp. lycopersici were tested by dual culture on plate. 【Result】The PCR products with three primer pairs were cloned and sequenced. The result showed that the sfp, ituA and fenB genes existed in the genome of B1619. The HPLC results showed that the peak time of 60% methanol eluent isolates were at 12,16.5 and 18 min, the secretion was 18.5 mg·L-1, and the retention times were consistent with bacillomycin L standards. The peak time of 70% methanol eluent isolates were at 22, 34, 37, 51 and 53 min, the secretion was 5.1 mg·L-1, and the retention times were consistent with fengycins standards. The peak time of 100% methanol eluent isolates were at 27, 37, 41, 51 and 53 min, the secretion was 74.3 mg·L-1, and the retention times were consistent with surfactins standards. The further verification of MALDI-TOF-MS results showed that 60% methanol eluent isolates which m/z were 1 043.4, 1 057.5 and 1 071.4 Da, was C13-C15 bacillomycin L, 70% methanol eluent isolates which m/z were 1 463.9, 1 477.9, 1 491.9 and 1 505.9 Da, was C15-C17 fengycins, 100% methanol eluent isolates which m/z were 1 008.6, 1 022.7 and 1 036.7 Da, was C13-C15 surfactins.  The mycostatic tests showed that the antifungal activities of 1 mg·mL-1 fengycins were higher than 1 mg·mL-1 bacillomycin L, and the 1 mg·mL-1 surfactins had the weakest effect onF. oxysporum. However, when the concentration of surfactins was increased to 3 and 6 mg·mL-1, the antifungal activities didn’t change obviously. 【Conclusion】B1619 strain secreted the three kinds of lipopeptide antibiotics in which fengycins and bacillomycin L played an important role in the inhibitory effect on F. oxysporum, while the surfactins had no obvious effect on it. Reference丨 Related Articles丨 Metrics

Effects of Bioorganic Fertilizers with Compound Microbes on Cucumber and Root-Knot Nematode     MA Yu-qin, WEI Cai, MAO Zhen-chuan, YANG Yu-hong, FENG Dong-xin, XIE Bing-yan Scientia Agricultura Sinica   2016,49(15 ):2945 -2954. DOI:10.3864/j.issn.0578-1752.2016.15.009 Abstract  （423） HTML （2） PDF（pc） （2524KB）（765） Save 【Objective】 The objective of this study is to evaluate the effects of bioorganic fertilizers with compound microbes (Brevibacillus brevis, Paecilomyces lilacinus, Acremonium implicatum, Trichoderma hamatum) on cucumber growth, yield and the control efficiency against root-knot nematode disease, then screen the efficient combinations of microbes.【Method】Experiments included 10 treatments of bioorganic fertilizers with compound microbes (No.1 to 10), which were from different compounds of the four kinds of microbes B. brevis, P. lilacinus, A. implicatum, and T. hamatum, the bioorganic fertilizers and the 10% fosthiazate granules were as the fertilizer and chemical control, respectively, the treatment without any fertilizer and pesticide was as the negative control. Based on the experiments performed in greenhouse and field, the differences of 10 treatments were analyzed by measuring the root-knot nematode disease index, cucumber yield, plant height and shoot fresh weight, and then the effects of bioorganic fertilizers with compound microbes on cucumber production and control efficiency of root-knot nematode disease were evaluated【Result】In pot experiments, the control efficiency of fosthiazate treatment was up to 89.2%, which was significantly higher than other treatments and controls. Among the 10 treatments of bioorganic fertilizers with compound microbes (No.1 to 10), the control efficiency of root-knot nematode of No. 5, No. 6, No. 9 treatments were 52.5%, 52.5%, and 54.2%, respectively, and the control efficiency of these treatments were higher than other fertilizer treatments. In the greenhouse plot, there was no significant difference in control efficiency among No. 5 (56.8%), No. 6 (57.6%), No. 9 treatments (59.3%) and fosthiazate treatment (61.3%). In addition, there was a significant positive correlation in the root-knot nematodes control efficiency between pot experiments and greenhouse plot, and the control efficiency of multi-microorganisms were better than that of single microorganism usually. Compared with the negative control, all fertilizer treatments increased cucumber growth and yield significantly (p＜0.01), but there were some difference among bioorganic fertilizers with compound microbes (No.1 to 10). In field trials, the yield increase was in the range of 31.7%-74.9%, the best treatment was No. 6, and the increased range of which was 74.9%. In pot experiment and greenhouse plot, compared with the negative control, the control efficiency of No. 9 ranked the best in yield, and the increased range was 60.4% and 68.1%, followed by No. 9 treatment, the control efficiency of No.1 were 50.8% and 55.8%, respectively. No. 5, No. 6 and No. 9 treatments could not only control the root-knot nematode disease effectively, but also promoted cucumber growth and increased their production, among them No. 9 treatment was the most effective treatment. There was a correlation in control efficiency of root-knot nematode and production increasing between pot experiment and greenhouse plot, but the correlation level was low. 【Conclusion】The bioorganic fertilizers with multi-microorganisms (No. 5, No. 6 and No. 9) have better effects on cucumber growth, yield and the control efficiency of root-knot nematode disease, thus possessing an important utilization value and research potential in agriculture production. Reference丨 Related Articles丨 Metrics

Natural Enemy Diversity on Trapping Crops and Its Application for Control of Aphids in Greenhouse Cucumber       WU Sheng-yong, XU Li-rong, LI Ning, WANG Deng-jie, LEI Zhong-ren Scientia Agricultura Sinica   2016,49(15 ):2955 -2964. DOI:10.3864/j.issn.0578-1752.2016.15.010 Abstract  （367） HTML （13） PDF（pc） （936KB）（887） Save 【Objective】Concern over protection and application of natural enemies for biological control of insect pests has increased considerably in recent years. The objective of this study is to assess the relationship between natural enemy diversity on multiple mixed trapping crops and its influence factors. Furthermore, the efficacy of banker plant system for control of the target pest aphids in cucumber greenhouse was evaluated. 【Method】Five species of trapping crops including maize, alfalfa, sunflower, wheat and soybean were mix-planted in the experiment stations of Langfang and Huanggang in 2012, 2103 and 2015, respectively. The species of natural enemies were investigated during the experimental period. The community parameters of natural enemies were calculated, and the relationship between community structure and its influence factors (plant species, sampling time and flowering phase) was analyzed by redundancy analysis. In 2013, the dominant natural enemy, i.e., ladybird beetle was collected from the trap cropping and stored in laboratory. In addition, the wheat aphid and wheat were selected as the alternative prey and banker plant of ladybird beetle with different densities, respectively, and the system for control of Aphis gossypii was introduced on greenhouse cucumber. The control efficacy among different treatments was compared.【Result】Analyses of community parameters of natural enemies, Shannon-Wiener diversity index (H’), Simpson’s diversity index (D) and Pielou’s evenness index (J) showed differences over the sampling time. Aphidius spp. and Propylaea japonica were determined as dominant natural enemies in two years. The abundances of both species accounted for over 10% in all natural species on the mixed trap cropping. Redundancy analysis results indicated that plant species, flowering phase and sampling time significantly affected the abundance of natural enemies, and in total explained 26.02% and 17.20% of the variance of the natural enemy community data in 2012 and 2015, respectively. Graph of RDA in 2012 and 2015 indicated that Orius spp. and Chrysoperla sinica displayed higher correlation with the flowering phase. When introduced the banker plant system with density of 200 ladybird beetles in greenhouse, the density of A. gossypii was significantly lower among the treatments, with a control efficacy of 69.4%. 【Conclusion】Attractiveness of natural enemies was integrated with the strategy of their enhanced abundance by means of artificial assistance. Different species of trapping crop plants were mix-planted, attracted multiple natural enemies groups. The dominant natural enemy attracted in the mixed plants was screened to develop the banker plant system, which was then introduced in greenhouse cucumber for control of aphids. The banker plant system with the highest density of ladybird beetle resulted in a certain reduction in aphids population. Therefore, it is practicable to integrated strategies involving the trapping, protection, screening and application of natural enemies for biological control of insect pests. Reference丨 Related Articles丨 Metrics

Effects of Different Control Strategies on the Structure of the Arthropod Community in the Cauliflower Field     ZENG Liang-bin, CHENG Yi, YAN Zhun, MA Jun, REN Shun-xiang, WEI Lin, XUE Zhao-dong Scientia Agricultura Sinica   2016,49(15 ):2965 -2976. DOI:10.3864/j.issn.0578-1752.2016.15.011 Abstract  （325） HTML （4） PDF（pc） （485KB）（630） Save 【Objective】The objective of this study is to reveal the effects of different control measures on characteristics of the arthropod animal community in the cauliflower field and provide a theoretical basis for pest control as well as protection and utilization of natural enemies. 【Method】The test ground of this work was divided into biological pesticide control area, chemical pesticide control area and non-pesticide control area. Five random sampling points were picked out and the numbers of all plants and arthropods on the test ground were recorded. Glass bottles with washing powders and water were placed on the set point of the field. The number of arthropod species in the ground was investigated. Cauliflower arthropod community in plots with different control measures were analyzed according to results. 【Result】There were 87 arthropod species in Guangzhou’s cauliflower field, including 29 insect pest species, 54 predator species and 4 neutral insect species. The control measures could obviously affect the diversity of species and the amount of each species of the arthropod communities. In non pesticide control area, the numbers of predators, insect pests and neutral insects were higher than those of the two pesticide control areas. The relationship of arthropod specie numbers and individual numbers among different areas was: non pesticide control area＞the biological pesticide control area＞the chemical pesticide control area. The dominant concentration of plant herbivore functional groups in cauliflower was at the minimum level at seeding stage and reached the maximum level at maturity stage. The dominant concentration of predatory natural enemies in different pesticide control areas was also relatively low at seedling stage. The concentration of the natural enemies remained at a similar level through different growth stages of the cauliflower in the non pesticide control area. On the other hand, the dominant concentration of predatory natural enemies fluctuated through different growth stages in pesticide control area. Cauliflower arthropod animal community varied at different growth stages and areas with different control measures. During the whole growth period, the species with the dominance index larger than 0.1 were Bemisia tabaci, Myzus persicae, Plutella xylostella, Pieris rapae, Pirata procurvus, Pardosa pseudoannulata and Coleosoma octomaculatum. The indices of cauliflower arthropod community diversity varied in different control areas and at different growth stages. Community overall diversity index (H′) increased following the cauliflower growth and reached maximum at late stage. These results coincided with the development of the field community. The trend of diversity index with different control measures was: non pesticide control area＞biological pesticide control area＞chemical pesticide control area. The variation of evenness index among different growth stages and different control measures was small. The variation trend in diversity of pest sub-communities and overall community was the same. The diversity index reached the maximum level in the late-mid period of cauliflower growth stage. The relationship among diversity indices with different control measures were: non pesticide control area＞biological pesticide control area＞chemical pesticide control area, which reached the minimum level at seedling stage of cauliflower in chemical pesticide control area. The evenness at cauliflower seedling stage was the maximum, and then decreased with the growth of cauliflower. In each growth period, the diversity of predator sub-community with different treatments remained relatively stable. The investigation results of the arthropod in the testing ground showed that the killing of the ground arthropod was larger in the two treatment areas. At the same time, it was possible to have a certain effect on the colonization of natural enemies at the early stage of the predatory natural enemies, according to the number of ground surface arthropod and the number of predatory natural enemies. Correlation of spiders with plant herbivore，neutral insects and predatory insects was significant. Correlation between predatory insects and neutral insects was also significant. These results indicated that between these functional groups in the number of compatibility or follow the effect. The correlation between predatory insects and insect herbivores was non-significant. 【Conclusion】The control measures could effectively reduce the population of pests, but also reduced the number of natural enemies. Neutral insects on ground surface would be helpful to early colonized predators. Chemical control could severely affect arthropod community of the cauliflower field, while the biological pesticide control has less influence on arthropod communities compared with the chemical pesticides. Reference丨 Related Articles丨 Metrics

Influence of Subculture on Virulence to Frankliniella occidentalis and Conidial Production of the Entomopathogenic Fungus Beauveria bassiana     ZHANG Hui, WU Sheng-yong, LI Juan, ZHANG Lu-lu, ZHANG Lin-ya, LEI Zhong-ren Scientia Agricultura Sinica   2016,49(15 ):2977 -2987. DOI:10.3864/j.issn.0578-1752.2016.15.012 Abstract  （386） HTML （1） PDF（pc） （476KB）（429） Save 【Objective】The objective of this study is to assess the capability of the Beauveria bassiana against Frankliniella occidentalisin the field, and explore the influence of subculture on virulence and conidial production of the B. bassiana, propose an effective method for preventing the retrogression during successive subculture, and provide a basis for the large-scale production technology of B. bassiana. 【Method】 The virulence of 28 fungal strains to adult F. occidentalis was evaluated by soaking method with B. bassiana concentration of 1×107 conidia/mL in the laboratory. The adults were dipped for 5 s in the conidial suspension. Conidial production of the 4 high virulent strains was measured on corn meal agar (CMA) medium and sabouraud dextrose agar yeast (SDAY) medium, screening high conidial production strain and spore production medium by comparing conidial production of different strains on different media. Subsequently, strain DZDC-9 was subcultured on three media (CMA medium, CMA medium with cicada exuviae, and CMA medium with F. occidentalis cadaver powder) to compare its virulence and conidial production over five subcultures. The relationship between conidial production and virulence was analyzed. 【Result】Among 28 strains of entomopathogenic fungi B. bassiana tested for virulence against F. occidentalis in laboratory bioassays, strains DZDC-9, GZGY-5, WLMQ1-8 and SZ-26 were found as the most potent. The corrected cumulative mortalities were over 90% after 5 days, and LT50<3 d. Conidial production obtained from the CMA medium of each strain was higher than from SDAY medium, and strain DZDC-9 had the higher conidial production among the four strains. The results demonstrated that the virulence of strain DZDC-9 declined with successive subculture. However, when the strain was subcultured on the CMA medium with 0.5% cicada exuviae or 0.5% F. occidentalis cadaver powder as an additive, the virulence increased with successive subculture. Conidial production was not significantly different between the same generation subculture on CMA medium with cicada exuviae and CMA medium with F. occidentalis cadaver powder, but they were significantly greater than conidial production obtained from CMA medium. A positive correlation was found between sporulation and virulence of B. bassiana conidia under different media and culture conditions.【Conclusion】The potential of B. bassiana strain DZDC-9 for the control of F. occidentalis was studied, and proposed an effective method for stabilizing the virulence and sporulation of B. bassiana. Conidial production could be used as an indicator for virulence evaluation. Reference丨 Related Articles丨 Metrics