Effect of Six Bacterial Strains on the Activity of Second Instar Larvae and Egg Hatching of Meloidogyne incognita

[Objectives]The paper was to screen effective biocontrol strains against Meloidogyne incognita.[Methods]The effect of six bacterial strains sourced from the research group s strain library on the activity of second instar larvae of M.incognita,as well as on egg hatching,was evaluated.[Results]The treatment of fermentation supernatant derived from the X-2 strain exhibited a pronounced lethal effect on M.incognita,with a corrected mortality rate reaching 97%within 72 h.Additionally,this treatment significantly inhibited egg hatching,achieving an inhibition rate of 94.69%at a 20-fold dilution.The strain was identified as Bacillus velezensis,belonging to the genus Bacillus,and was designated as RKN1111.[Conclusions]This study presents alternative strains and a theoretical framework for the biological control of M.incognita.

The Overwintering Capability of Ulva prolifera Spores and Gametes in the Yellow Sea,China

Green tides caused by the bloom of Ulva prolifera have affected the Yellow Sea annually since 2007.To explore the intrinsic causes of successive blooms,field investigations and indoor simulation experiments were conducted using micro-propagules of U.prolifera.From January to February 2014,micro-propagules of various green algae,including U.prolifera,Ulva flexuosa,and Ulva linza,were prevalent in the coastal waters of Rudong,Lianyungang,and Qingdao.However,in March 2014,micro-propagules of U.prolifera were not detected in the coastal waters of Lianyungang and Qingdao.Neither the spores nor gametes of U.prolifera can germinate at temperatures below 5℃.At 2℃and 5℃,U.prolifera spores and gametes could survive for 1-3 months at a light intensity range of 0-30μmol m^(-2)s^(-1)and for less than 1 month if the light intensity exceeded 30μmol m^(-2)s^(-1).By integrating indoor experiments and field investigations,this study found that U.prolifera spores and gametes could overwinter in the Rudong coastal area,which is an important factor for the annual emergence of recurring green tides in the Yellow Sea.

The Performance of Black Soldier Fly Larvae (BSFLs), Hermetia illucens L. (Diptera: Stratiomyidae), as a Function of the Substrate Used: A Review

Organic wastes are one of the greatest challenges that cities face worldwide. In numerous underdeveloped nations, like Cameroon, waste is often disposed of through landfills, composting, or open-air combustion. Unfortunately, the concept of waste sorting and organic waste processing is new to many individuals. This has led to an increase in the amount of organic waste and the costs connected with its management. Consequently, the majority of developing nations have sought out waste management solutions that are more cost-effective. Therefore, it has been determined that the bioconversion of organic wastes by black soldier fly larvae (BSFLs) (Hermetia illucens) into multifunctional prepupae is a viable alternative. Appreciation is given to the employment of the organic waste management approach in developing nations since it is not only environmentally friendly and economically viable, but also provides a means for waste valorisation through the production of diverse resources and potential economic benefits. Studies have proved the usefulness of the insect in controlling organic wastes, but countries such as Cameroon are still unfamiliar with the nuances of this method. Consequently, this timely review examined the performance of the BSFL, specifically in organic waste treatment, as well as the best practices for multiplying them to determine its viability for use in a waste treatment plant, the production of high-quality larvae as a source of protein for livestock, and the production of diesel fuel.

Biodiesel Production from Rhynchophorus ferrugineus Larvae Oil: Physichochemical Properties and Acid Composition of Oil as Affected by Oil Extraction Protocol

Biodiesel, a renewable energy source made from natural oils and fats, can be produced using white raffia larvae as a raw material. These larvae have a high lipid content and a short life cycle, making them suitable for this purpose. One crucial step in biodiesel production is oil extraction, and this study aimed to investigate how the extraction protocol affects the fuel properties of the oil. To study the impact of solvent type, solvent volume, and residence time on oil yield, 200 grams of Rhynchophorus ferrugineus were used in a Soxhlet extractor. The researchers examined the physicochemical properties and fatty acid composition of the crude grease using the European biodiesel standard (EN14214) and gas chromatography methods, respectively. The study found that hexane as a solvent produced the highest oil yield (64.44%) during a four-hour extraction period with a solvent ratio of 300 ml. Furthermore, the hexane-extracted oil had the highest iodine number (3.02 g/100 g) and cetane number (55.69). These values indicate favorable properties for biodiesel production. The Rhynchophorus ferrugineus larvae oil proved to be a rich source of monounsaturated fatty acids (76%), which were found to be significantly affected by the solvent type. Based on quality assessment, Rhynchophorus ferrugineus can be suitable for biodiesel production. In summary, under the given operational conditions, hexane is the most suitable solvent for Rhynchophorus ferrugineus oil extraction for biodiesel production. Further research in optimizing the extraction process can contribute to the efficient utilization of renewable energy sources like white raffia larvae for biodiesel production.

A Case Report on Cutaneous Larva Migrans (CLM)

Cutaneous larva migrans (CLM) is a zoonotic hookworm infection of dogs and cats commonly found in low-income countries in the tropical and subtropical regions and travellers to these regions. It is caused by invasion of the skin by the parasitic larvae of hookworms which, after entry, move under the skin causing an inflammatory reaction resulting in a single or multiple tracks. Patients commonly present with a progressive, itchy, erythematous serpiginous skin rash, affecting the feet, although it can affect any other parts of the body. The diagnosis is mainly clinical, based on history and physical examination. Treatment of this condition can effectively be achieved with either albendazole or ivermectin. We present a case of a 7-year-old boy who was diagnosed with CLM after presenting to the hospital with a history of a progressive itchy rash with tracks on the left foot. Although CLM is a self-limiting disease, it causes a lot of suffering and, therefore, it is of public concern. There is a need to increase awareness of this disease among health workers, and to implement and promote preventive measures against the disease since the cause is known.

Study on the Quantity Dynamic Changes of Heterobacteria and Vibrios in Larvae Industrialized Culture System

[ Objective ] The dynamic change of heterobacteria and vibrios in larvae industrialized culture system was studied to provide scientific reference for healthy cultivation of shrimp. [ Method ] The heterobacteria, vibrios and pathogenic vibrio parahaemolyticus were monitored in larvae industrialized culture system. [ Result] The heterobacteria, vibrios and pathogenic vibrio parahaemolyticus were the most in fertilized eggs of shrimp but the least in nauplius, then their number would increase with growth. During whole rearing period, both boterobacteria in larvae, vibrios in water would increase by one order of magnitude, while both vibrios in larvae and heterobacteria in water would increase by two orders of magnitude. There were many heterobacteria and vibrios but few vibrio parahaemolyticus in living bait. The correlation coefficients between larvae and heterobacteria and vibrios in water were 0. 704 and 0. 840 in culture system respectively, while the correlation among heterobacteria, vibrios in living bait and larvae, water were weak or negative. [ Conclusion ] There was a dynamic relation between water and larvae in rearing period, and restrictly control of culture condition would restrain the occurrence of disease caused by vibrio parahaemolyticus, besides that bacteria number in bait was not obviously correlated with bacteria nubmer in culture system.

Research of Holotrichia diomphalia Larvae Cultivation Technology with Agaricus bisporus Residues

[Objective] The aim was to explore key technology to cultivate Holotdchia diomphalia larvae with Agaricus bisporus residues and to provide, technologicar sup- ports for processing of Agaricus bisporus residues. [Method] In the research, fodder thickness, population density and residues under different treatments were set to re- search effects on Holotrichia diomphalia larvae. [Result] The optimal thickness of fodder was 25 cm and the optimal feeding density was 44-56 larvae per hectare. The dry residues were more suitable, compared with decomposed residues and corn bran powders, for cultivation of Holotrichia diomphalia larvae. [Conclusion] Cultivation of Holotrichia diomphalia larvae with Agaricus bisporus residues is a new method to make use of Agaricus bisporus residues and of significance for extension of agricul- tural circulation chain, increase of economic benefits and ecological benefits.

Observation of Biological Characteristics of Bananamoth[Opogona sacchari (Bojer)]Larvae in Sugarcane

[ Objective] The paper was to understand the biological characteristics of bananamoth [ Opogona sacchari （ Bojer ） ] larvae in sugarcane. [ Method ] Through the rearing test of bananamoth larvae with different hosts, the biological characteristics of bananamoth larvae in sugarcane were observed and analyzed. [ Result ] The mortality rate of bananamoth larvae reared with sugarcane was higher than that of the pests reared with potato. The larva had 8 instars, and the devel- opment duration of the larvae reared with sugarcane was 34.6 d longer than the pests reared with potato. The larvae needed about 98.8 d to complete a generation in average. Viewed from the observation values of head width, body length and weight of larvae, bananamoth larvae reared with sugarcane basically accorded with the growth and development law of larvae. [Condusion ] The results provided theoretical basis for the preparation of effective measures against bananamoth and the assurance of safe production of.sugarcane.

Overwintering Safe Storage Methods and Regional Division of Seed-stem of Cassava in China

[Objective] In this study,the climatic features and overwintering sage storage methods of seed-stem of cassava in cassava-planting areas were investigated aiming at providing a technical guidance for sustainable development of cassava industry in China.[Method] The seed-stem of cassava was overwintered through keeping in field,piling up in the open air,burying in soil or piling up in greenhouses in Hepu,Nanning and Laibin of Guangxi,Hunan and Zhejiang.After the beginning of spring,the survival buds in seed stem of cassava were counted.And then the survival rates of buds were calculated for different storage methods.[Result] In Hepu,where the seed-stem of cassava was piled up in the open air for overwintering,the survival rates of buds were all higher than 90.00%.In particular,the survival rate of buds in seed-stem of cassava that was buried shallowly in the open field was highest（94.38%）.In Nanning,the seed-stem of cassava that was stored in greenhouses had the highest survival rate（94.98%） of buds.In Laibin,the seed-stem of cassava was usually stacked in greenhouses.Thus the survival rates of buds were almost all higher than 89.60%.Particularly,the survival rate of buds in seed-stem of cassava that was buried horizontally in soil and covered with sugarcane leaves reached the peak（98.79%）.In Jiangyong and Hangzhou,the seedstem of cassava was stored in specific facilities.So the survival rates of buds were relatively high.[Conclusion] In the frost-free areas south of 21.6° N（south of Maoming（Guangdong）-Hepu（Guangxi）-Jinghong（Yunnan））,the seed-stem of cassava can be buried shallowly in the open air or stacked and covered with film.In the light to heavy-frost areas（21.6° N-23.8° N,south of Qingyuan（Guangdong）-Laibin（Guangxi）-Lincang（Yunnan））,the seed-stem of cassava can be stacked in greenhouses,stacked and covered with film in the open air or buried vertically in greenhouses.In the heavy-frost areas and low-temperature areas north of 23.8° N（north of Qingyuan（Guangdong）-Laibin（Guangxi）-Lincang（Yunnan） to HunanJiangxi-Zhejiang）,the seed-stem of cassava can be stored in coldness-resistant caves or cellars or stacked vertically in greenhouses along with small sheds.

Control Effects of Several Technical Measures on Overwintering Generation of Oriental Fruit Moth in Peach Orchard

Peeling trunk,binding insect-attracting belt,cleaning orchard and soil-covering under the crown were the control methods on overwintering generation of oriental fruit moth.However,they had not been applied widely on the production because of the lack of systematic quantitative evaluation.Aiming at this fact,the control effects of these technical measures were studied in peach with different ripening period.The results showed that peeling trunk was the best with the control effect of88.64%.The control effect of binding insect-attracting belt of grass bundle was74.13%,which was the most economical and efficient.Covering with soil layer of 3cm under the crown during the middle ten days of March could holdback the adult getting out from soil.Cleaning deadwood could clean out the overwintering larvae on the ground.

Investigation and Analysis of Spawning Site of Overwintering-generation Chilo suppressalis(Walker) Adults on Rice Seedlings

Chilo suppressalis （Walker） is one of the important pests in rice produc-tion. ln this paper, the spawning condition of Chilo suppressalis on rice seedlings in Wuxue, Qichun, Chongyang and Xiaogan of Hubei Province was investigated, and the spawning habit of overwintering-generation Chilo suppressalis on rice seedlings was analyzed. The results showed the overwintering-generation Chilo suppressalis prefers to spawn on verdant rice leaf blades （face, upper part）. The investigation on spawning habit of Chilo suppressalis would provide a theoretical basis for the fore-casting and control of Chilo suppressalis.

Analysis on Survival Rate and Economic Benefit of Apostichopus japonicus Larvae Reared by Raising Water Temperature

In order to control the spawning quality and improve the economic benefit of Apostichopus japonicus Selenka, the indoor temperature and light control methods were employed for artificial maturation, spawning and hatching of A. japonicus, and the larval survival rate, disease incidence rate and economic benefit were analyzed. The results showed that compared with those of conventional temperature-reared larvae, the survival rate of raised temperature-reared larvae was increased by 15.8%, the disease incidence rate was reduced by 10.2%, and the economic benefit was improved by 21.6%. These results will provide theoretical basis and technical support for the artificial breeding of A. japonicus.

Pesticidal character of phytoecdysteroids from Ajuga multiflora Bunge (Labiatae) on larvae of Cryptorrhynchus lapathi L. (Coleoptera: Curculionidae)

Eight kinds of phytoecdysteroids extracted from different parts of Ajuga multiflora Bunge (Labiatae) that were collected from different places at different time were tested for killing effects on the 2-instar larvae of Cryptorrhynchus lapathi L by adding them to the artificial diet of larvae. The experimental results indicated that adding 1-3-mL phytoecdysteroids to the artificial diet could lead 58%-100% of 2-instar larvae of C. lapathi to death within 24 days. The phytoecdysteroids extracted from the whole plant of A. multiflora which was collected before flowering time were much more effective than those extracted from the plants collected at flowering and after flowering periods, and the modified mortality rate of larvae reached 65.22%, 85.07%, and 98.11% at the dosage level of 1-mL, 2-mL, and 3-mL extracts, respectively. The extract made from root of A. multiflora plant was more effective in killing efficiency than those from stem and leaves, and the average death rates of larvae were up to 100%, 98.20% and 98.32% at dosage levels of 1-mL, 2-mL, and 3-mL extracts, respectively. The killing speed of the extracted phytoecdysteroids was slower than that of triflumuron, hexaflumuron or deltamethrin emulsifiable concentrate. The mortality rate of larvae is closely related to the feeding duration on the diets containing phytoecdysteroids. Feeding on the diets with addition of phytoecdysteroids for 16 days, more than 80% of treated 2-instar larvae of C. lapathi were led to death. The killing effect of the extracts was little affected by the growth areas of A. multiflora plant and the adding way to artificial diet.

Study on Chironomid Larvae Recognition Based on DWT and Improved KNN

A chironomid larvae images recognition method based on wavelet energy feature and improved KNN is developed. Wavelet decomposition and color information entropy are selected to construct vectors for KNN that is used to classify of the images. The distance function is modified according to the weight determined by the correlation degree between feature and class, which effectively improves classification accuracy. The result shows the mean accuracy of classification rate is up to 95.41% for freshwater plankton images, such as chironomid larvae, cyclops and harpacticoida.

The Dynamic Changes in Cold Tolerance of Ground-cover Chrysanthemum Growing in the Open Field during the Overwintering

The ground-cover chrysanthemum （Dendranthemaxgrandiflorum Kitamura） ＇Zixunzhang＇ was used as the experimental material in this study. The physiological and biochemical indexes of leaves, emergent rhizomes and roots from ＇Zixunzhang＇ growing in the open field during the autumn and winter in Beijing area were deter- mined. These indexes showed that root activities decreased slowly with the drop in temperature. The relative water contents of leaves and emergent rhizomes, and the water content of roots decreased. The activities of SOD, CAT and POD from leaves and emergent rhizomes were affected significantly by low temperature, but their change trends were different, which suggested that these 3 enzymes might play an interacted role in the formation of the cold tolerance of ＇Zixunzhang＇ mum, while the changes of the three enzyme activities in roots were little when the tem- perature dropped. With the significant increasing of the content of soluble sugar from leaves, the contents of soluble protein and proline declined overall; and the contents of osmotic regulation substances of emergent rhizomes and roots increased at first and then decreased. The correlation analysis indicated that the cold toler- ance of ground-cover mum ＇Zixunzhang＇ was related closely to relative water con- tents, SOD enzyme activity, soluble protein, soluble sugar and root activity. The morphological observation of leaves, emergent rhizomes and roots also showed that the survival of the ground-cover mum mainly depended on the cold tolerance of roots during the overwintering.

Hermetia illucens larvae as a potential dietary protein source altered the microbiota and modulated mucosal immune status in the colon of finishing pigs

Background: Insects, such as Hermetia illucens larvae, are rich in chitin and proteins, and represent a suitable feed ingredient replacement for animals. However, little is known about the effect of administering H. illucens larvae on intestinal microbiota, bacterial metabolite profiles, and mucosal immune status in animals. This study aimed to investigate the effects of administering H. illucens larvae on colonic microbiota and bacterial metabolites production in finishing pigs. Seventy-two crossbred(Duroc × Landrace × Large White) female pigs(initial body weight, 76.0 ± 0.52 kg) were randomly allocated to three different dietary treatments: a control diet(Control group) and two diets corresponding to 4%(H1 group) and 8%(H2 group) H. illucens larvae inclusion levels, respectively. Each treatment consisted of eight pens(replicates), with three pigs per pen. After 46 days of feeding, eight pigs per treatment(n =8) were slaughtered, and the colonic digesta and mucosa were collected for microbial composition and microbial fermentation products, and genes expression analyses.Results: The results showed that the H1 diet significantly increased the abundance of Lactobacillus,Pseudobutyrivibrio, Roseburia, and Faecalibacterium compared with those in the control group(P < 0.05), with a decrease in the abundance of Streptococcus. The numbers of Lactobacillus, Roseburia, and Clostridium cluster XIVa were significantly greater in the H1 group than in the control group(P < 0.05). Meanwhile, H2 diet increased the number of Clostridium cluster XIVa compared with the control group(P < 0.05). For colonic metabolites, total short chain fatty acids, butyrate, and isobutyrate concentrations were significantly higher in the H1 group than those in the control group(P < 0.05);the H1 treatment caused a striking decrease in protein fermentation compared with the control group, as the concentrations of total amines, cadaverine, tryptamine, phenol, p-cresol, and skatole were significantly lower(P < 0.05). Additionally, H2 diet also increased butyrate concentration compared with control group(P < 0.05), while decreased the concentrations of phenol, p-cresol, and skatole(P < 0.05). Pigs in the H1 group down-regulated the expression of TLR-4 and pro-inflammatory cytokines(IFN-γ) compared with pigs in the control group(P < 0.05), and up-regulated anti-inflammatory cytokine(IL-10) and intestinal barrier genes(ZO-1, occludin, and mucin-1). H2 diet up-regulated the expression of ZO-1 compared with control group(P < 0.05). Furthermore, the changes in the colonic mucosal gene expression were associated with changes in the bacterial composition and their metabolites.Conclusions: Collectively, dietary inclusion of Hermetia illucens larvae may enhance mucosal immune homeostasis of pigs via altering bacterial composition and their metabolites. These findings provide a new perspective on insect meal as a sustainable protein source rich in nutrient ingredients for swine.

Genetic Analysis of Cryotolerance in Cotton During the Overwintering Period Using Mixed Model of Major Gene and Polygene

The joint analysis of the mixed genetic model of major gene and polygene was conducted to study the inheritance of cryotolerance in cotton during the overwintering period.H077（G.hirsutum L.,weak cryotolerance） and H113（G.barbadence L.,strong cryotolerance） were used as parents.Cryotolerance of six generation populations including P1,P2,F1,B1,B2,and F2,from each of the two reciprocal crosses H077×H113 and H113×H077 were all investigated.The results showed that cryotolerance in cotton during the overwintering period was accorded with two additive major genes and additivedominance polygene genetic model.For cross H077×H113,the heritabilities of major genes in B1,B2,and F2 were 83.62,76.84,and 90.56%,respectively;and the heritability of polygene could only be detected in B2,which was 7.76%.For cross H113×H077,the heritabilities of major genes in B1,B2,and F2 were 67.42,68.95,and 83.40%,respectively;and the heritability of polygene was only detected in F2,which was 6.51%.In addition,the whole heritability in F2 was always higher than that in B1 and B2 in each cross.Therefore,for the cryotolerance breeding of perennial cotton,the method of single cross recombination or single backcross should be adopted to transfer major genes,and the selection in F2 would be more efficient than that in other generations.

Lead levels of Culex mosquito larvae inhabiting lead utilizing factory

Objective:To determine lead level primarily in Culex quinquefasciatus(Cx.quinquefasciatus), and Culex gelidus(Cx.gelidus) larvae inhabiting lead consuming factories,and to putatively estimate eco-toxicological impact of effluents from the firms.Methods:Third instars larvae were sampled by standard dipping method and lead concentrations in the larvae and their respective surrounding factory aquatic environments were determined through standard atomic absorption spectrophotometry(AAS).Results:Cx.quinquefasciatus was the most abundant species followed by Cx.gelidus.The levels of lead were higher in the Cx.quinquefasciatus(1.08-47.47μg/g),than in the wastewaters surface(0.01-0.78 μg/mL) from the factories or closer areas around factories. Other species were not reaching the.criteria for lead determination.Conclusions:The Cx. quinquefasciatus larvae can bio-accumulate the metal and can potentially serve as a biomarker of lead contamination,to complemente conventional techniques.

Comparison of Different Cultivars of Blueberry Overwintering Ability in Qingdao of China

In order to select severe overwintering abilitied blueberry cultivars for cold resistance of annual branches, promoting breeding high quality cultivars, a study had been conducted into field-planting shoots overwintering ability and the relative conductivity, MDA content, SOD of 7 different kinds of blueberries under artificial cooling process. According to survey results, under field conditions, Different cultivars of blueberries showed significantly difference, ranging from 56.67% of Bluegold to 12.80% of Darrow. With the temperature decreasing, changes of relative conductivity, MDA content and SOD in annual branches had a strong regularity and the hardiness of these cultivars is: Northland > Chippewa > Coville > Bluecroup > Darrow > Bluegold > Powderblue.

Spatiotemporal distribution of fish eggs and larvae in the Huanghe(Yellow) River estuary, China in 2005–2016

Decreasing fish resources in estuaries is a subject of anthropogenic activities. Studies of the spatiotemporal distribution of fish eggs and larvae can help identify the status and processes underlying recruitment in a fishery. As the fifth largest river estuary in the world, the Huanghe (Yellow) River estuary (HRE) is a typical estuary that has been seriously aff ected by human activities. Annual surveys on ichthyoplankton and environmental factors were conducted in the months of May of 2005 and 2009-2016 in the HRE to investigate the spatiotemporal distribution of fish eggs and larvae and the associated infl uencing factors. A total of 23 and 20 species of eggs and larvae, respectively, were collected. The dominant orders were Perciformes (51.2%) and Clupeiformes (25.6%). The average number of fish species eggs and larvae were 6.0 and 4.1 in average abundance of 0.91 and 0.13 ind./m^3 , respectively. The dominant species were mainly low-commercial-value small-sized fishes, such as Clupanodon punctatus , Harengula zunasi, and Acanthogobius, whereas certain traditional commercial fishes, such as Trichiurus lepturus , and Clupea pallasii, were not seen. Analysis of the fish egg and larval community revealed four temporal assemblages and two spatial assemblages. Salinity was the main factor on the spatial distribution of ichthyoplankton communities, the species number and Shannon-Weiner diversity index (H′) of the fish egg and larval community near the river mouth with lower salinity were signifi cantly lower than the community far away from the river mouth with higher salinity. In addition, increases of water temperature promoted the number and abundance of fish species eggs, and the areas of abundant prey tended to have a more diversified and abundant of ichthyoplankton species. In overall, overfishing, dam construction, and other human activities were the main drivers that led to the substantial decline in fishery resources in the HRE.