CRISPR-based genetic control strategies for insect pests

Genetic control strategies such as the sterile insect technique have successfully fought insect pests worldwide. The CRISPR(clustered regularly interspaced short palindromic repeats) technology, together with high-quality genomic resources obtained in more and more species, greatly facilitates the development of novel genetic control insect strains that can be used in area-wide and species-specific pest control programs. Here, we review the research progress towards state-of-art CRISPR-based genetic control strategies, including gene drive, sex ratio distortion, CRISPRengineered genetic sexing strains, and precision-guided sterile insect technique. These strategies’ working mechanisms,potential resistance development mechanisms, and regulations are illustrated and discussed. In addition, recent developments such as stacked and conditional systems are introduced. We envision that the advances in genetic technology will continue to be one of the driving forces for developing the next generation of pest control strategies.

Species and Control Techniques of Main Diseases and Insect Pests of Camellia oleifera in Anhui Province

[Objectives]The paper was to master the species,incidence regularity and control techniques of main diseases and insect pests of Camellia oleifera in Anhui Province.[Methods]The species of main diseases and insect pests of C.oleifera in major C.oleifera afforestation bases and seedling bases in Anhui Province were investigated through field survey and literature search.Afterwards,the symptom characteristics,occurrence regularity and harms of diseases and insect pests were analyzed,and scientific and reasonable control techniques were put forward.[Results]The main diseases of C.oleifera in Anhui Province were soft rot disease,blister blight,anthracnose,sooty blotch,etc.,and the main insect pests were Euproctis pseudoconspersa,Biston marginata,Hypomeces squamosus,Curculio chinensts,Chrenoma atritarsis,etc.The control techniques mainly included ecological regulation,physical prevention and control,chemical prevention and control,and biological prevention and control.[Conclusions]The results will promote the high-quality development of C.oleifera industry in Anhui Province,and contribute to the improvement of China s edible vegetable oil supply and national grain and oil security.

Effect of Nitrogen Fertilizer on Herbivores and Its Stimulation to Major Insect Pests in Rice

Nitrogen is one of the most important factors in development of herbivore populations. The application of nitrogen fertilizer in plants can normally increase herbivore feeding preference, food consumption, survival, growth, reproduction, and population density, except few examples that nitrogen fertilizer reduces the herbivore performances. In most of the rice growing areas in Asia, the great increases in populations of major insect pests of rice, including planthoppers （Nilaparvata lugens and Sogatella furcifera）, leaffolder （ Cnaphalocrocis rnedinalis）, and stem borers （Scirpophaga incertulas, Chilo suppressalis, S. innotata, C. polychrysus and Sesarnia inferens） were closely related to the long-term excessive application of nitrogen fertilizers. The optimal regime of nitrogen fertilizer in irrigated paddy fields is proposed to improve the fertilizer-nitrogen use efficiency and reduce the environmental pollution.

Effects of silicon amendment on the occurrence of rice insect pests and diseases in a field test

Rice is one of the most important staple foods for the world population,but it is attacked by a number of destructive pests.While evidence from greenhouse and laboratory tests has shown that silicon（Si）amendment can confer enhanced resistance to pests in rice,few studies have directly demonstrated the Si-mediated protection from pests in a field situation.In this study,field plots with silicon amendments at 0,75,150 and 300 kg SiO2 ha-1 in early-and late-season rice were employed to evaluate the effects of silicon amendment on the occurrence of major insect pests and diseases and rice yield.Compared with the control plots without silicon amendment,plant damage by stem borer and leaf folder and population size of planthopper were significantly lower in three to five of the seven monitoring observations in each season in the plots amended with 300 kg SiO2 ha-1.The disease index of rice blast in the early-season rice was lower in the plots amended with Si at 300 kg SiO2 ha-1 than in the control plots,while Si protection from rice blast in the late-season rice and from rice sheath blight in the early-season rice were not apparent.An insignificant increase of rice yield by 16.4%（604 kg ha-1）was observed in the plots amended with 300 kg SiO2 ha-1 over the control plots.Our results indicate that Si amendment at 300kg SiO2 ha-1 can provide substantial protection from some of the rice pests under field conditions.These findings support the recommendation of silicon amendment as a key component of integrated management of rice pests.

The Predatory Function of Three Spiders to Two Insect Pests in Rice Within a Multi-species Co-existence System

The prey-seeking behavior of three spiders (X1-Pirata subpiraticus, X2-Clubiona japonicola and X3-Tetragnatha japonica) for brown plant hopper (X4-Nilaparvata lugens) and rice spittle bug (X5-Cal-litettix versicolor) was investigated, as well as how interference between and within species occurred, by using a quadratic regression rotational composite design. Six predation models derived from the analysis of interactions among and within predators and preys were developed. The total predatory capacity of spiders on rice insect pests after coexistence for one day can be expressed as follows: Y3 = 32.795 + 2.25X1 + 1.083X2 + 0.5X3 + 10.167X4 + 3.167X5 - 1.67X12 - 2.42X22 - 3.295X32 - 0.045X42 + 0.455X52 - 3.125X1X2 + 0.375X1X3 -0.625X1X4 - 0.375X1X5 + 0.375X2X3 - 0.875X2X4 + 0.125X2X5 + 0.375X3X4 - 0.375X3X5 + 0.125X4X5. The principal efficiency analysis using this model indicated that increases in insect pest density significantly increased predation by predators; this was much greater than the effect of any single predator. X4 had a greater effect than X5; however, X4 and X5 demonstrated little interspecific interference and even promoted each other and increased predation rates as the densities of the two pests increased. Among the three predators, an increase in the density of X, had the greatest effect on the increase in predation, X3 had the second, X2 the third greatest effect. As predator density increased inter- and intra-species interference occurred, which were largely related to the size, activity, niche breadth, niche overlap and searching efficiency of the predators. X2 produced the greatest interference between different individuals and between any other predator species. X3 had the second greatest, which reduced predation levels at high predator densities. Because of these factors, the highest predation rate was obtained at a prey density of 120 per 4 rice-hills. The optimal proportion of the three predators in the multi-predator prey system was X1: X2: X3 = 5.6:1.3:4.1.

Determinants of species assemblages of insect pests in alpine forest ecosystems of western China

Background:Insect pests are a significant threat to natural resources and social development.Modeling species assemblages of insect pests can predict spatiotemporal pest dynamics.However,research gaps remain regarding the mechanism for determining species assemblages of insect pests in alpine forest ecosystems.Here,we explored these determinants using a field investigation conducted for insect pests in a region of the Qinghai-Tibet Plateau.We assessed the species assemblages of insect pests in alpine forest ecosystems based on species co-occurrence patterns and species diversity(i.e.,observed diversity,dark diversity,community completeness,and species pool).A probabilistic model was used to test for statistically significant pairwise patterns of species co-occurrence using the presence-absence matrix of pest species based on species interactions.We used ordinary least squares regression modeling to explore relationships between abiotic factors(i.e.,climate factors and human influence)and species diversity.Results:Positive pest species interactions and many association links can occur widely across different investigation sites and parts of plant hosts in alpine forest ecosystems.We detected high dark diversity and low community completeness of insect pests in alpine forest ecosystems.High temperature and precipitation could promote pest species diversity,particularly dark diversity and species pools.Human influence could drive high levels of pest species diversity and lead to dark diversity and species pools.Community completeness could be an effective indicator for insect pest risk assessment.Conclusions:Our study provides new evidence for the determinants of insect pest species assemblages in alpine forest ecosystems from the perspectives of pest species interactions and abiotic factors.The findings of our study could reveal the mechanism for shaping species assemblages and support the prevention and control of insect pests in alpine forest ecosystems.

A Stably Transgenic INA Enterobacter cloacae for Control of Insect Pests

Using the minitransposon pMini-Tn5 and the ice-nucleation active (INA) gene of iceA, a suicide recombinant plasmid pTnice1 was constructed, which has the ability of broad-host-range conjugal mobilization and integration of iceA into chromosomal DNA of many gram-negative bacteria by Tn5 transposition. We used this plasmid to integrate the iceA into chromosomal DNA of Ent. cloacae and obtained the transgentic strain Enc1.2022 ina. In this transgenic Ent. cloacae, iceA would never be transferred elsewhere through transposition, and constantly expressed high ice nucleation activity even in the absence of antibiotic pressure. The transgenic strain was ingested by corn borer larvae. Over the 7 d after ingestion, the mean supercooling points (SCPs) of the larvae was about 10℃ higher than those of larvae treated with distilled water (control). The maintenance of these high SCPs was related to the stable gut colonization of transgenic strain. At 6th day post ingestion, the larva was exposed at 5 or 7℃ for 12 h, the percentages of larvae frozen to death were 85 and 100%, respectively. In contrast, none or a small proportion of control larvae was frozen to death under the same conditions. Further studies demonstrated that this transgenic strain bore weak epiphytic ability. Therefore, this genetically engineered strain may be a promising candidate for control of insect pests in agricultural fields.

A Brief Introduction of Main Diseases and Insect Pests in Soybean Production in the Global Top Five Soybean Producing Countries

The United States, Brazil, Argentina, India and China are the major soybean producing countries in the world. Nearly 90% of the world^s soybean production comes from these countries. The occurrence of diseases and insect pests often lead to the reduction of soybean yield, and brings varying degree losses to these countries. This article provides an overview of the impact and measures on soybean main diseases and insect pests in the top five major soybean producing countries over the world. It is concluded that the diseases affecting the soybean yield seriously include Phakopsorapachyrhizi, Heterodera glycines, Septoria glycines, Colletotrichum spp. and Macrophominaphaseolina; and the main insect pests include Anticarsia gemmatalis, Spodoptera litura, Nezara viridula and Frankliniella occidentalis, which will provide information for key prevention and control of soybean main diseases and insect pests in these countries.

A New Strategy of Insect Pest Control:Down-regulating Cotton Bollworm Gene Expression by Engineering Plant Double Stranded RNA

Cotton bollworm(Helicoverpa armigera) is an important agricultural pest that causes severe yield loss to crops,particularly to cotton.Transgenic Bt crops have been successful in

Occurrence and Control of Main Soybean Diseases and Insect Pests in Greater Mekong Sub-region

Soybean rust,soybean downy mildew,and soybean thrips,soybean pod borers,and soybean nocturnal moths are the world wide diseases and insect pests in soybean production,which pose a potential threat to soybean production in Great Mekong Sub-region（ GMS）,comprising Cambodia,Lao People＇s Democratic Republic,Myanmar,Thailand,Vietnam,and Yunnan province,the People＇s Republic of China. This paper summarized the host range,epidemiology,damage and control methods of these diseases and insect pests in GMS,with the aim to provide information basis for understanding and effective control of soybean diseases and insect pests in GMS.

Analysis and Study on Characteristics and Detection Methods of Cotton Diseases and Insect Pests

[Objectives]The paper was to find the diseases and insect pests in the process of cotton growth quickly,effectively and timely.[Methods]The growth process of cotton was dynamically monitored by UAV aerial photography,and the aerial data map was converted into geotif image with longitude and latitude and then inputted into the detection system for preprocessing,mainly for image feature extraction and classification.Through deep learning of MATLAB software and BP neural network algorithm,the feature similarity of the images in the established characteristic database of cotton diseases and insect pests was compared.[Results]Through comparative analysis of characteristics of a large number of diseases and insect pests,it was found that deep learning method had high discrimination accuracy and good reliability.[Conclusions]The dynamic detection system using deep learning can well find cotton diseases and insect pests,and achieve early detection and early treatment,so as to effectively improve the yield and quality of cotton.

Integrated Prevention and Control Technology of Major Diseases and Insect Pests of Strawberry

In order to effectively deal with the problems of diseases and insect pests in the growth process of strawberry and to improve the quality and yield of strawberry,the main diseases and insect pests in strawberry cultivation such as powdery mildew,gray mold,anthracnose,red stele root rot,calcium deficiency,salt or fertilizer damage,aphids,red spiders,thrips,grubs,etc.and their identification methods were analyzed.The comprehensive pollution-free prevention and control techniques of these pests and diseases were explored,in order to provide technical guidance for high quality,efficient and harmless production of strawberry.

Species and Occurrence Regularity of Diseases and Insect Pests Harming Baccaurea ramiflora Lour. in Guangxi

[Objectives]The paper was to understand the species and harm of diseases and insect pests of Baccaurea ramiflora Lour.in Guangxi,and to provide basis for the prevention and control of diseases and insect pests.[Methods]From 2018 to 2021,a systematic investigation on diseases and insect pests of B.ramiflora was conducted in Dongxing City,Fangchenggang City,Longzhou County,Pingxiang City,Jingxi City and Napo County in Guangxi.[Results]There were 22 species of diseases and insect pests that harmed B.ramiflora in Guangxi,7 of which were diseases and 15 were insect pests.Leaf blight(Fuasrium spp.)was the main disease at seedling stage,causing severe damage,and anthracnose(Colletotrichum gloeosporioides Penz.)caused moderate damage.Cyclosia papilionaris Drury and Chrysochus chinensis Baly had high frequency of occurrence,wide damage area and severe damage.Cyclosia panthono Stoll and Lcerya aegyptiaca Douglas caused moderate damage,while other insect pests caused light damage.[Conclusions]The study lays a foundation for the scientific prevention and control of B.ramiflora diseases and insect pests,and promotes the sustainable and rapid development of B.ramiflora industry in Guangxi.

Green Prevention and Control Technology against Main Diseases and Insect Pests of Facility Tomato

In recent years,with the increasing planting area of facility tomato,diseases and insect pests such as tomato grey mold(Botrytis cinerea),early blight(Alternaria solani),late blight(Phytophthora infestans),and whitefly(Trialeurodes uaporariorum) occur frequently,causing severe harms and difficulties in prevention and control.In order to ensure the normal production of facility tomato and improve the yield and quality of tomato,the corresponding prevention and control measures are put forward according to the regularity of the occurrence of diseases and insect pests and the characteristics of facility environment,which has certain guiding significance for agricultural production.

Insect Pests Control of Okra (Abelmoschus esculentus) by Using Plant Aqueous Extracts in Korhogo Area (Northern Côte d’Ivoire, West Africa)

In this study,we monitored for the impact of three aqueous extracts of plants(Azadirachta indica,Hyptis suaveolens and Solanum lycopersicum)on insect pests abundance in okra(Abelmoschus esculentus L.)crop,compared to a synthetic chemical«SAUVEUR 62 EC»,having as active ingredients,acetamiprid 32g/l and Lambda-cyhalothrin 30g/l.Foliar applications by these extracts were done using manual sprayers.After treatment,the insects were caught using two methods(pitfall traps and colored bowls traps).A total of 6505 insects belonging to nine orders were recorded in four plots.The plot 1(9 orders)was the most diverse,followed by the plot 3(8 orders),the plot 2 and 4(7 orders respectively).Coleoptera,Lepidoptera,Diptera,Orthoptera and Hemiptera were the most frequents.The chemical treatment has impacted significantly the number of orders(p<0.05)but,the insect abundance was impacted significantly by the different biological treatments(p<0.05).This study showed that the aqueous extract of Solanum lycopercicum was more effective on the abundance of pests belonging to Hemiptera,while the aqueous extracts of Azadirachta indica and Hyptis suaveolens were effectives on the abundance of pests belonging to Coleoptera.The chemical treatment was effective on the pests belonging to both orders.

Invasion genetics of alien insect pests in China: Research progress and future prospects

An unwelcome side effect of the globalization of the world's economy and dramatic increase in human mobility and trade has been a marked increase in species invasions that have posed severe threats to the ecological, economic, and/or social stability of the introduced regions. In this review, we analyzed the application of molecular markers in invasion genetics of invasive alien insect pests(IAIPs) in China based on a bibliometric survey. Our report discusses the considerable progress that has been made during the past two decades in understanding the invasion genetics of IAIPs in China. We reviewed the major findings in the main topics including the effects of origin and routes of invasion on genetic structure, spatial and temporal genetic changes, factors contributing to the genetic changes of IAIPs, and genetic mechanisms involved in IAIPs' invasions. On the other hand, some of these research areas remain relatively unexplored in China, especially those pertaining to spatial and temporal genetic changes of IAIPs and genetic mechanisms of IAIPs' invasions. Finally, the future research prospects of IAIPs in China are discussed. We hope this review will stimulate an interest in and provide an increased understanding of the field of invasion genetics of IAIPs in China, and provide a basis for future research in this area.

Biological Control of Insect Pests of Agricultural Crops through Habitat Management Was Discussed

Biological control through habitat management leads to sustainable insect pest control. Different types of land composition such as multiple landscapes, patchiness of landscapes enhance the natural enemies which ultimately lead to control of insect pest. Plant characteristics such as flower shape, flower color and blooming period ensures excess food for natural enemies like nectar and pollen. Moreover, some agricultural practices such as tillage, crop rotation, and intercropping influence the natural enemies especially parasitoid and preda-tors. Consequently, they increase longevity and fecundity of parasitoid and predator that help to control insect pest. One of the most important recently used methods is push-pull which consists of semiochemicals called Herbi-vore-Induced Plant Volatiles (HIPVs). This compound has been used to pre-vent pest and attract natural enemies.

Diversity of Insect Pest and Predator Species in Monsoon and Summer Rice Fields of Taungoo Environs, Myanmar

Paddy fields are natural and artificial wetland ecosystems that supply rice for the people and provide the wildlife especially insect diversity of different functional aspects. A total of 71 insect species belonging to 40 families under eight orders were observed during the study period. Among the 71 insect species, 18 species of beetles, nine species of bugs, eight species of dragonfly, five species of butterflies, four species of leafhoppers, plant hoppers and moths, three borer and spiders, two crickets, one species of skippers, grass hopper, hispa, ant, weevil, hairy caterpillar, leaf roller, katydid, thrips, maggot and water boatmen were recorded in the study sites. Total of 41 species of pests, 18 species of predators and 12 species of beneficial species (they function as pollinating the flowering plants in the paddy field wetland ecosystem) were recorded in the study sites. In the monsoon season, the 41 species of pest species, 18 species of predator species and 12 species of beneficial species were recorded from monsoon rice field. According to Shannon Evenness value (H'/S = -0.012564), the data showed that the insect species recorded from the one habitat was not the similar to another. In summer paddy fields, 36 species of pest species, 16 species of predator species and 9 species of beneficial species were recorded. Total arthropod insect species were recorded 61 species from the dry rice fields. According to Shannon Evenness value (H'/S = -0.000120), the data showed that the insect species recorded from the one habitat was not the similar to another. Population growth and duration of life cycle of insects is mainly dominated by the temperature, the duration of life cycle is shorter in the high temperature than in the low temperature.

Evaluation and screening for resistance of some varieties(lines)to major diseases and insect pests of rice

During 1984-1988,2,231 varieties(lines)from International Rice Testing Program(IRTP)were evaluated and screened for resistance to riceblast(Bl),bacterial blight(BB),sheath blight