scholarly journals The Effects of Temperature on the Development, Morphology, and Fecundity of Aenasius bambawalei (=Aenasius arizonensis)

Insects ◽  
2021 ◽  
Vol 12 (9) ◽  
pp. 833
Author(s):  
Juan Zhang ◽  
Yayuan Tang ◽  
Jun Huang
Keyword(s):  
High Temperature ◽  
Natural Enemies ◽  
Morphological Changes ◽  
Insect Pest ◽  
Hind Tibia ◽  
Developmental Rate ◽  
Female Offspring ◽  
Developmental Duration ◽  
Phenacoccus Solenopsis ◽  
Different Temperatures

The effects of high temperature on the developmental, morphological, and fecundity characteristics of insects, including biological invaders and their accompanying natural enemies, are clear. Phenacoccus solenopsis (Homoptera: Pseudococcidae) is an aggressive invasive insect pest worldwide. Aenasius bambawalei (=Aenasius arizonensis Girault) (Hymenoptera: Encyrtidae) is a predominant accompanying parasitoid of this mealybug. Our previous studies showed that temperature change induced an increase in the female offspring ratio of A. bambawalei. However, whether this increase is the result of a shortened or enhanced development period of the reproductive systems of A. bambawalei remains unknown. Here, we compared the pupal development, hind tibia of female adults, and fecundity of A. bambawalei under different temperatures to clarify the development and morphological changes induced by high temperature and to better understand its potential as an accompanying natural enemy. Our results showed that, at a high temperature (36 °C), the pupal developmental duration of A. bambawalei was only 0.80 times that of the control, and the length of the hind tibia was 1.16 times that of the control. Moreover, high temperature accelerated the developmental rate of gonads and increased the numbers of eggs and sperm. These results indicated that experimental warming shortened the pupal developmental duration, altered the hind tibia length of female adults, and facilitated the fecundity of A. bambawalei. These findings will help to understand the adaptation mechanisms of accompanying natural enemies. Furthermore, these findings will help to make use of this behavior to effectively control invasive pests.

scholarly journals Morphometry of the reproductive system of the predator Podisus nigrispinus (Dallas, 1851) (Hemiptera, Pentatomidae) when submitted to different temperatures

2020 ◽  
Vol 50 (12) ◽  
Author(s):  
Ítala Tainy Barreto Francisco dos Santos ◽  
Heloisa Safira Santos Pinheiro ◽  
Júlio César Melo Poderoso ◽  
Vancleber Batista dos Santos ◽  
Thiago Xavier Chagas ◽  
...  
Keyword(s):  
Natural Enemies ◽  
Reproductive System ◽  
Adult Stage ◽  
Mass Rearing ◽  
Developmental Duration ◽  
Temperature Variations ◽  
Temperature Conditions ◽  
Controlled Conditions ◽  
Different Temperatures ◽  
Ovariole Number

ABSTRACT: In order to manipulate the mass rearing of natural enemies, temperature variations can be used. The effects are widely studied for their survival and developmental duration; however, there is little information about their reproductive system in the literature. Therefore, the purpose of this study was to evaluate the effects of different temperatures on the reproductive system of the predator Podisus nigrispinus (Dallas, 1851) (Hemiptera: Pentatomidae). The predator was kept at temperature conditions of 17, 21, 25, and 29 °C until reaching 15 days of age, the adult stage. The insects were then killed, measured for both weight and size, dissected, and then evaluated for the following parameters: length of the most developed ovariole; number of ovarioles per ovary; number of oocytes per the more developed ovarioles; number of oocytes per P. nigrispinus female; and the total area of the testicles was measured in the male insects. Results showed that as the temperature increased, the parameters were positively affected. These temperature variations can be used to manipulate the mass rearing of P. nigrispinus under controlled conditions.

scholarly journals GERMINATION AND VIGOUR IN SEEDS OF THE COWPEA IN RESPONSE TO SALT AND HEAT STRESS

2019 ◽  
Vol 32 (1) ◽  
pp. 143-151 ◽  
Author(s):  
Luma Rayane de Lima Nunes ◽  
Paloma Rayane Pinheiro ◽  
Charles Lobo Pinheiro ◽  
Kelly Andressa Peres Lima ◽  
Alek Sandro Dutra
Keyword(s):  
Salt Stress ◽  
Heat Stress ◽  
High Temperature ◽  
Low Temperature ◽  
Vigna Unguiculata ◽  
Salt Concentration ◽  
Dry Weight ◽  
Germination Percentage ◽  
Different Types ◽  
Different Temperatures

ABSTRACT Salinity is prejudicial to plant development, causing different types of damage to species, or even between genotypes of the same species, with the effects being aggravated when combined with other types of stress, such as heat stress. The aim of this study was to evaluate the tolerance of cowpea genotypes (Vigna unguiculata L. Walp.) to salt stress at different temperatures. Seeds of the Pujante, Epace 10 and Marataoã genotypes were placed on paper rolls (Germitest®) moistened with different salt concentrations of 0.0 (control), 1.5, 3.0, 4.5 and 6.0 dS m-1, and placed in a germination chamber (BOD) at temperatures of 20, 25, 30 and 35°C. The experiment was conducted in a completely randomised design, in a 3 × 4 × 5 scheme of subdivided plots, with four replications per treatment. The variables under analysis were germination percentage, first germination count, shoot and root length, and total seedling dry weight. At temperatures of 30 and 35°C, increases in the salt concentration were more damaging to germination in the Epace 10 and Pujante genotypes, while for the Marataoã genotype, damage occurred at the temperature of 20°C. At 25°C, germination and vigour in the genotypes were higher, with the Pujante genotype proving to be more tolerant to salt stress, whereas Epace 10 and Marataoã were more tolerant to high temperatures. Germination in the cowpea genotypes was more sensitive to salt stress when subjected to heat stress caused by the low temperature of 20°C or high temperature of 35°C.

scholarly journals Insect fauna of pests and their natural enemies inhabiting sorghum-panicles in Egypt

2019 ◽  
Vol 29 (1) ◽  
Author(s):  
Hosam M. K. H. El-Gepaly
Keyword(s):  
Natural Enemies ◽  
Dominant Species ◽  
Insect Pest ◽  
Pest Species ◽  
Parasitoid Species ◽  
Insect Fauna ◽  
Cryptoblabes Gnidiella ◽  
Arthropod Species ◽  
Lepidopteran Pests ◽  
Major Pest

AbstractSorghum panicles offer a very rich microenvironment for many insect pest species and their natural enemies. Thirty arthropod species belonging to 28 families, pertaining to 9 orders were obtained from sorghum panicles planted in Sohag Governorate, Egypt, during the 3 successive seasons of 2016–2018. Out of these species were 14 pests, 16 predators, and 3 parasitoids. Lepidopteran and hemipteran pests were the most dominant species-infested sorghum-panicles during the mature stages of the panicles. Three microlepidopteran pests, the noctuid, Eublemma (Autoba) gayneri (Roth.); the pyralid, Cryptoblabes gnidiella Millière, and the cosmopterigid, Pyroderces simplex Walsingham, were recorded as major pest species infesting sorghum panicles in Sohag Governorate. The dipteran parasitoid species, Nemorilla floralis (Fallen) (Tachinidae) emerged from the pupae of the E. gayneri and C. gnidiella, while the hymenopteran parasitoid, Brachymeria aegyptiaca (Chalcididae) was obtained from the pupae of all the studied microlepidopteran pests. Spiders, coccinellids, and Orius spp. were the dominant predators collected form panicles. Post-harvest, larvae, and pupae of lepidopteran pests, especially P. simplex recorded (147, 96, and 79 larvae) and (47, 30, and 73 pupae)/10 panicles in 2016, 2017, and 2018 seasons, respectively.

scholarly journals Investigating the Parasitoid Community Associated with the Invasive Mealybug Phenacoccus solenopsis in Southern China

Insects ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 290
Author(s):  
Hua-Yan Chen ◽  
Hong-Liang Li ◽  
Hong Pang ◽  
Chao-Dong Zhu ◽  
Yan-Zhou Zhang
Keyword(s):  
Biological Control ◽  
Species Delimitation ◽  
Southern China ◽  
Insect Pest ◽  
Integrated Approach ◽  
Molecular Data ◽  
Coi Gene ◽  
Morphological Examination ◽  
Accurate Identification ◽  
Phenacoccus Solenopsis

The cotton mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae), is an emerging invasive insect pest in China. Hymenopteran parasitoids are the key organisms for suppressing populations of P. solenopsis in the field, and therefore could be used as biological agents. Accurate identification of the associated parasitoids is the critical step to assess their potential role in biological control. In this study, we facilitated the identification of the parasitoid composition of P. solenopsis using an integrated approach of species delimitation, combining morphology with molecular data. Eighteen Hymenoptera parasitoid species belonging to 11 genera of four families are recognized based on morphological examination and molecular species delimitation of the mitochondrial cytochrome c oxidase 1 (COI) gene and the 28S rDNA using the automatic barcode gap discovery (ABGD) and the Bayesian Poisson tree processes model (bPTP). Among these species, eight species are primary parasitoids with Aenasius arizonensis (Girault) (Hymenoptera: Encyrtidae) being the dominant taxon, while the other 10 species are probably hyperparasitoids, with a prevalence of Cheiloneurus nankingensis Li & Xu (Hymenoptera: Encyrtidae). These results indicate that parasitoid wasps associated with P. solenopsis from China are diverse and the integrated taxonomic approach applied in this study could enhance the accurate identification of these parasitoids that should be assessed in future biological control programs.

scholarly journals Factors influencing the occurrence of fall armyworm parasitoids in Zambia

2020 ◽  
Author(s):  
Léna Durocher-Granger ◽  
Tibonge Mfune ◽  
Monde Musesha ◽  
Alyssa Lowry ◽  
Kathryn Reynolds ◽  
...  
Keyword(s):  
Biological Control ◽  
Natural Enemies ◽  
Smallholder Farmers ◽  
Insect Pest ◽  
Fall Armyworm ◽  
Parasitoid Species ◽  
Maize Crop ◽  
Parasitism Rates ◽  
Control Programmes ◽  
Interest In Research

AbstractInvasive alien species have environmental, economic and social impacts, disproportionally threatening livelihood and food security of smallholder farmers in low- and medium-income countries. Fall armyworm (FAW) (Spodoptera frugiperda), an invasive insect pest from the Americas, causes considerable losses on maize to smallholder farmers in Africa since 2016. The increased use of pesticides to control FAW in Africa raises concerns for health and environmental risks resulting in a growing interest in research on biological control options for smallholder farmers. In order to evaluate the occurrence of local natural enemies attacking FAW, we collected on a weekly basis FAW eggs and larvae during a maize crop cycle in the rainy season of 2018–2019 at four locations in the Lusaka and Central provinces in Zambia. A total of 4373 larvae and 162 egg masses were collected. For each location and date of collection, crop stage, the number of plants checked and amount of damage were recorded to analyse which factors best explain the occurrence of the natural enemy species on maize. Overall parasitism rates from local natural enemies at each location varied between 8.45% and 33.11%. We identified 12 different egg-larval, larval and larval-pupal parasitoid species. Location, maize growth stage, pest density and larval stage significantly affected parasitoid species occurrence. Our findings indicate that there is potential for increasing local populations of natural enemies of FAW through conservation biological control programmes and develop safe and practical control methods for smallholder farmers.

scholarly journals Experimental Investigation of Wave Velocity-Permeability Model for Granite Subjected to Different Temperature Processing

Geofluids ◽  
2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
Guanghui Jiang ◽  
Jianping Zuo ◽  
Teng Ma ◽  
Xu Wei
Keyword(s):  
Particle Size ◽  
High Temperature ◽  
Wave Velocity ◽  
Pore Fluid ◽  
Rock Matrix ◽  
Permeability Model ◽  
Wave Velocities ◽  
Before And After ◽  
Different Temperatures ◽  
Increasing Temperature

Understanding the change of permeability of rocks before and after heating is of great significance for exploitation of hydrocarbon resources and disposal of nuclear waste. The rock permeability under high temperature cannot be measured with most of the existing methods. In this paper, quality, wave velocity, and permeability of granite specimen from Maluanshan tunnel are measured after high temperature processing. Quality and wave velocity of granite decrease and permeability of granite increases with increasing temperature. Using porosity as the medium, a new wave velocity-permeability model is established with modified wave velocity-porosity formula and Kozeny-Carman formula. Under some given wave velocities and corresponding permeabilities through experiment, the permeabilities at different temperatures and wave velocities can be obtained. By comparing the experimental and the theoretical results, the proposed formulas are verified. In addition, a sensitivity analysis is performed to examine the effect of particle size, wave velocities in rock matrix, and pore fluid on permeability: permeability increases with increasing particle size, wave velocities in rock matrix, and pore fluid; the higher the rock wave velocity, the lower the effect of wave velocities in rock matrix and pore fluid on permeability.

A Method for Predicting the Behavior of Plastics at Different Temperatures

2014 ◽  
Vol 1039 ◽  
pp. 107-111
Author(s):  
Yang Chen ◽  
Gui Qin Li ◽  
Bin Ruan ◽  
Xiao Yuan ◽  
Hong Bo Li
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Constitutive Model ◽  
Research And Development ◽  
Mechanical Behavior ◽  
Plastic Material ◽  
Different Temperatures ◽  
Plastic Parts

The mechanical behavior of plastic material is dramatically sensitive to temperature. An method is proposed to predict the mechanical behavior of plastics for cars, ranging from low-temperature low temperature ≤-40°C to high temperature ≥80°C. It dominates the behavior of plastic material based on improved constitutive model in which the parameters adjusted by a series of tests under different temperatures. The method is validated with test and establishes the basis for research and development of plastic parts for automobile as well.

Experimental Research on Bond Strength between Rebar and Concrete after High Temperature

2011 ◽  
Vol 71-78 ◽  
pp. 1057-1061 ◽  
Author(s):  
Ke Fang Yin ◽  
Yang Han ◽  
Yi Liu
Keyword(s):  
Reinforced Concrete ◽  
High Temperature ◽  
Bond Strength ◽  
Experimental Research ◽  
Bonding Strength ◽  
Different Temperatures ◽  
Ultimate Bond Strength

With the centrally pulling-out test, the bond strength of reinforced concrete is measured with different temperatures and different cooling ways after high temperature; and the ultimate bond strength and slip of reinforced and concrete under different conditions are analyzed. The results show that the bonding strength declines gradually with the increase of temperature, and the ultimate slippage also decreases gradually.

scholarly journals Application of Trap Cropping as Companion Plants for the Management of Agricultural Pests: A Review

Insects ◽  
2018 ◽  
Vol 9 (4) ◽  
pp. 128 ◽  
Author(s):  
Shovon Chandra Sarkar ◽  
Endong Wang ◽  
Shengyong Wu ◽  
Zhongren Lei
Keyword(s):  
Pest Management ◽  
Natural Enemies ◽  
Natural Enemy ◽  
Insect Pests ◽  
Cropping Systems ◽  
Insect Pest ◽  
Critical Time ◽  
Trap Crops ◽  
Companion Plant ◽  
Trap Cropping

Companion planting is a well-known strategy to manage insect pests and support a natural enemy population through vegetative diversification. Trap cropping is one such type of special companion planting strategy that is traditionally used for insect pest management through vegetative diversification used to attract insect pests away from the main crops during a critical time period by providing them an alternative preferred choice. Trap crops not only attract the insects for feeding and oviposition, but also act as a sink for any pathogen that may be a vector. Considerable research has been conducted on different trap crops as companion plant species to develop improved pest management strategies. Despite this, little consensus exists regarding optimal trap cropping systems for diverse pest management situations. An advantage of trap cropping over an artificially released natural enemy-based biological control could be an attractive remedy for natural enemies in cropping systems. Besides, many trap crop species can conserve natural enemies. This secondary effect of attracting natural enemies may be an advantage compared to the conventional means of pest control. However, this additional consideration requires a more knowledge-intensive background to designing an effective trap cropping system. We have provided information based on different trap crops as companion plant, their functions and an updated list of trap cropping applications to attract insect pests and natural enemies that should be proven as helpful in future trap cropping endeavors.

scholarly journals Investigation of Fatigue Behavior of ABS and PC-ABS Polymers at Different Temperatures

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 1818
Author(s):  
Andrea Mura ◽  
Alessando Ricci ◽  
Giancarlo Canavese
Keyword(s):  
High Temperature ◽  
Room Temperature ◽  
Working Condition ◽  
Fatigue Behavior ◽  
Polymeric Materials ◽  
Cyclic Loads ◽  
Structural Components ◽  
Working Temperature ◽  
Different Temperatures ◽  
Positive Effect

Plastics are widely used in structural components where cyclic loads may cause fatigue failure. In particular, in some applications such as in vehicles, the working temperature may change and therefore the strength of the polymeric materials. In this work, the fatigue behavior of two thermoplastic materials (ABS and PC-ABS) at different temperatures has been investigated. In particular, three temperatures have been considered representing the working condition at room temperature, at low temperature (winter conditions), and high temperature (summer conditions and/or components close to the engine). Results show that high temperature have big impact on fatigue performance, while low temperatures may also have a slight positive effect.

Sign in / Sign up

Export Citation Format

Share Document