scholarly journals The Process of Aphid Egg-Laying and the Little Known Role of the Coccinellidae in Aphid Egg Destruction in Poland – Preliminary Results

2014 ◽  
Vol 54 (3) ◽  
pp. 242-249
Author(s):  
Magdalena Lubiarz ◽  
Elżbieta Cichocka
Keyword(s):  
Developmental Stages ◽  
Egg Laying ◽  
Pedunculate Oak ◽  
Egg Survival ◽  
Metopolophium Dirhodum ◽  
Preliminary Results ◽  
Ladybird Beetles ◽  
Egg Destruction ◽  
Dog Rose

Abstract No detailed studies have been conducted in Poland with regard to aphid eggs or egg survival in particular. So far, no studies have been conducted concerning the role of ladybird beetles in reducing the number of aphid eggs in spring, before the development of leaves, and in autumn, after the leaves have been shed. At these times, other developmental stages of aphids are unavailable as food for the ladybirds. The paper presents the preliminary results of a three-year study on the process of aphid egg-laying (especially Chaetosiphon tetrarhodum, Macrosiphum rosae, Metopolophium dirhodum, and Maculolachnus submacula). The paper also deals with the little known role of ladybirds in aphid egg destruction. Research was conducted in Otrębusy (Western Mazovia), Poland, in the years 2008-2010, on the rugosa rose and on the dog rose. In the years 2011-2013, in Otrębusy, the occurrence of M. submacula was also observed on the ornamental grandiflora rose. Furthermore, in the years 2003-2004, observations were conducted on the pedunculate oak in Polesie National Park and in the town of Puławy (Lublin Region), Poland. The observations which took place in Puławy focused on egglaying of aphids representing the genera Phylloxera and Lachnus. The study investigated aphid oviposition sites. Data was collected on the number of aphid eggs noted on the studied plants. The study also showed, that sometimes winter eggs of aphids could provide nutrition for ladybirds. This was especially true in autumn when ladybird beetles were preparing for hibernation.

scholarly journals RNA Interference-Based Silencing of the Chitin Synthase 1 Gene for Reproductive and Developmental Disruptions in Panonychus citri

Insects ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 786
Author(s):  
Muhammad Waqar Ali ◽  
Muhammad Musa Khan ◽  
Fang Song ◽  
Liming Wu ◽  
Ligang He ◽  
...  
Keyword(s):  
Rna Interference ◽  
Developmental Stages ◽  
Essential Gene ◽  
Egg Laying ◽  
Chitin Synthase ◽  
Treatment Rate ◽  
Panonychus Citri ◽  
Citrus Red Mite ◽  
First Time

Chitin synthase 1 (CHS1) is an essential gene regulating chitin during different developmental stages of arthropods. In the current study, we explored for the first time the role of CHS1 gene regulation in the citrus red mite, Panonychus citri (McGregor) (Acari: Tetranychidae), by silencing its expression using (RNA interference) RNAi-based strategies. The results reveal that P. citri tested in different developmental stages, including larvae, protonymphs, deutonymphs, and adults fed on sweet orange leaves dipped in various concentrations (200, 400, 600, and 800 ng/μL) of dsRNA-PcCHS1, resulted in a continuous reduction in their gene expression, and the extent of transcript knockdown was positively correlated with the concentration of dsRNA. Concentration–mortality response assays revealed a mortality of more than 50% among all the studied developmental stages, except for adulthood. Furthermore, the target gene dsRNA-PcCHS1 treatment of larvae, protonymphs, deutonymphs, and females at a treatment rate of 800 ng/mL of dsRNA significantly decreased the egg-laying rates by 48.50%, 43.79%, 54%, and 39%, respectively, and the hatching rates were also considerably reduced by 64.70%, 70%, 64%, and 52.90%, respectively. Moreover, using the leaf dip method, we found that the RNA interference effectively reduced the PcCHS1 transcript levels by 42.50% and 42.06% in the eggs and adults, respectively. The results of this study demonstrate that the RNAi of PcCHS1 can dramatically reduce the survival and fecundity of P. citri, but the dsRNA concentrations and developmental stages can significantly influence the RNAi effects. These findings indicate the potential utility of the PcCHS1 gene in causing developmental irregularities, which could aid in the development of effective and novel RNAi-based strategies for controlling P. citri.

Oviposition site selection in three species of European Newts (Salamandridae) genus Triturus

1995 ◽  
Vol 16 (3) ◽  
pp. 265-272 ◽  
Author(s):  
Claude Miaud
Keyword(s):  
Site Selection ◽  
Laboratory Experiments ◽  
Breeding Site ◽  
Egg Laying ◽  
Oviposition Site ◽  
Oviposition Site Selection ◽  
Egg Survival ◽  
Natural Breeding ◽  
Linear Shape

AbstractOviposition site selection in Triturus helveticus, T. alpestris and T. cristatus was studied both in natural and laboratory situations. In a natural breeding site, eggs of the three species were not laid equally on several plants: T. cristatus laid practically all their egges on only one plant (Nasturtium officinale) while T. helveticus eggs were collected on four plant species. In laboratory experiments, plastic and cotton fabric supports made it possible to test ovipositing female selectivity according to flexibility and shape of support and egg-laying distance below the surface. In all three species, a high proportion of eggs were laid on supports of linear shape (as opposed to arborescent shape) and egg frequency decreased as a function of depth (from 0 to 40 cm below the surface). Selection according to flexibility was also observed, the smallest species (T. helveticus) laying more eggs on the thinner supports. The role of support selectivity during oviposition in Triturus is discussed, in term of proximate (i.e. female protection against predators, breathing necessity) and ultimate (i.e. egg survival) factors, and related to new ecology.

scholarly journals Crayfish hemocytes develop along the granular cell lineage

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Fang Li ◽  
Zaichao Zheng ◽  
Hongyu Li ◽  
Rongrong Fu ◽  
Limei Xu ◽  
...  
Keyword(s):  
Developmental Stages ◽  
Cell Lineage ◽  
Granular Cell ◽  
Marker Genes ◽  
Hematopoietic Tissue ◽  
Differentiated Cells ◽  
Stage Of Development ◽  
Almost All ◽  
Relationship Of

AbstractDespite the central role of hemocytes in crustacean immunity, the process of hemocyte differentiation and maturation remains unclear. In some decapods, it has been proposed that the two main types of hemocytes, granular cells (GCs) and semigranular cells (SGCs), differentiate along separate lineages. However, our current findings challenge this model. By tracking newly produced hemocytes and transplanted cells, we demonstrate that almost all the circulating hemocytes of crayfish belong to the GC lineage. SGCs and GCs may represent hemocytes of different developmental stages rather than two types of fully differentiated cells. Hemocyte precursors produced by progenitor cells differentiate in the hematopoietic tissue (HPT) for 3 ~ 4 days. Immature hemocytes are released from HPT in the form of SGCs and take 1 ~ 3 months to mature in the circulation. GCs represent the terminal stage of development. They can survive for as long as 2 months. The changes in the expression pattern of marker genes during GC differentiation support our conclusions. Further analysis of hemocyte phagocytosis indicates the existence of functionally different subpopulations. These findings may reshape our understanding of crustacean hematopoiesis and may lead to reconsideration of the roles and relationship of circulating hemocytes.

The sociobiological aspects of the National Survey on Fecundity and Fertility in Belgium

1969 ◽  
Vol 1 (4) ◽  
pp. 369-388 ◽  
Author(s):  
R. L. Cliquet
Keyword(s):  
National Survey ◽  
Evaluation Method ◽  
Modern Society ◽  
Western Society ◽  
Gene Frequencies ◽  
Potential Fecundity ◽  
Preliminary Results ◽  
Human Needs ◽  
Belgian Population

SummaryIn 1966, a National Survey on Fecundity and Fertility was organized in Belgium. Approximately 3000 married women under 41 years of age and living with their husbands were interviewed and asked about their reproductive histories. The present paper records the sociobiological aims and methods and some preliminary results of this survey. The aims were to:(1) study the influences of contraception on human needs and qualities, in this case mainly potential fecundity;(2) study the influence of attempts to increase the potential fecundity level in modern society on fecundity gene frequencies;(3) study the influences of the overall socio-cultural environment on fecundity and fertility variables with particular reference to differences in social status in Western society;(4) analyse the role of social assortment of fecundity and fertility variables on the biological structure, and possibly the composition, of modern populations.A relatively large, but far from complete body of data has been collected on a number of individual fecundity and fertility variables, on the medical processes employed to increase fecundity, on contraception, and on a number of conventional sociological and demographic variables.The principles underlying the present approach to the study of fecundity are explained, and a few preliminary results for one of the general fecundity classifications are shown.The information collected on contraception has been qualitatively analysed and a correction and evaluation method is described. Data on the use of the different contraceptive methods show that substantial sections of the Belgian population are limiting their family size in a way which is inefficient, from both sexual and familial standpoints.

scholarly journals Epigenetic transgenerational inheritance, Gametogenesis and Germline Development

2021 ◽  
Author(s):  
Millissia Ben Maamar ◽  
Eric E Nilsson ◽  
Michael K Skinner
Keyword(s):  
Developmental Biology ◽  
Environmental Factors ◽  
Biological System ◽  
Developmental Stages ◽  
Primordial Germ Cell ◽  
Cell Types ◽  
Transgenerational Inheritance ◽  
Germline Development ◽  
Current Review

Abstract One of the most important developing cell types in any biological system is the gamete (sperm and egg). The transmission of phenotypes and optimally adapted physiology to subsequent generations is in large part controlled by gametogenesis. In contrast to genetics, the environment actively regulates epigenetics to impact the physiology and phenotype of cellular and biological systems. The integration of epigenetics and genetics is critical for all developmental biology systems at the cellular and organism level. The current review is focused on the role of epigenetics during gametogenesis for both the spermatogenesis system in the male and oogenesis system in the female. The developmental stages from the initial primordial germ cell through gametogenesis to the mature sperm and egg are presented. How environmental factors can influence the epigenetics of gametogenesis to impact the epigenetic transgenerational inheritance of phenotypic and physiological change in subsequent generations is reviewed.

Improving Juvenile Justice for Females: A Statewide Assessment in California

2002 ◽  
Vol 48 (4) ◽  
pp. 526-552 ◽  
Author(s):  
Barbara Bloom ◽  
Barbara Owen ◽  
Elizabeth Piper Deschenes ◽  
Jill Rosenbaum
Keyword(s):  
Developmental Stages ◽  
State Agencies ◽  
Specific Policy ◽  
Statewide Assessment ◽  
Female Adolescence ◽  
Staffing And Training ◽  
Substance Abuse Education ◽  
Gender Specific ◽  
And Training

This article reports findings from a survey of officials from various California state agencies and a series of interviews and focus groups with female youth and professionals serving this population. The study examined types of services provided, program barriers, and facilitation of change. The findings were used to make gender-specific policy and program recommendations. The authors found that meeting the needs of girls and young women requires specialized staffing and training, particularly in terms of relationship and communication skills, gender differences in delinquency, substance abuse education, the role of abuse, developmental stages of female adolescence, and available programs and appropriate placements and limitations. Effective programming for girls and women should be shaped by and tailored to their real-world situations and problems. In order to do this, a theoretical approach to treatment that is gender-sensitive and that addresses the realities of girls' lives must be developed.

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