scholarly journals Genetic Characterization of Six Stocks ofLitopenaeus vannameiUsed in Cuba for Aquaculture by Means of Microsatellite Loci

2012 ◽  
Vol 2012 ◽  
pp. 1-7
Author(s):  
Anna Pérez-Beloborodova ◽  
Adriana Artiles-Valor ◽  
Lourdes Pérez-Jar ◽  
Damir Hernández-Martínez ◽  
Missael Guerra-Aznay ◽  
...  

Four microsatellite loci were used to achieve genetic characterization of six stocks fromLitopenaeus vannameiused for aquaculture in Cuba: second generation from first introduction (S2-1), first generation from the second one (S1-2), from the third one (S1-3), and the fourth one (S1-4) and the crossings from two parental population: first generation from the first with first generation from the third (S1-1 × S1-3) and first generation from the second with first generation from the third (S1-2 × S1-3). 66% (16/24) of genetic systems in total loci were in genetic disequilibrium. The four microsatellite loci were polymorphic for all six stocks. Major quantities of allelic variants correspond to locus Pvan 1758, which is at the same time that one where there are private alleles from first generation of the third. All Fst comparisons were significant. This indicates big differences between stocks. The highest values are those in which there is presence of the second introduction. This introduction and its descendants are also more consanguineous.

2017 ◽  
Vol 53 (4) ◽  
pp. 472-482 ◽  
Author(s):  
A. E. Girnyk ◽  
A. A. Vergun ◽  
A. V. Omelchenko ◽  
V. G. Petrosyan ◽  
V. I. Korchagin ◽  
...  

1965 ◽  
Vol 97 (12) ◽  
pp. 1303-1318 ◽  
Author(s):  
H. J. Herbert

AbstractIn Nova Scotia one leaf cluster with an adjoining 1 inch of twig taken from the inside of each of 10 apple trees replicated four times is an adequate sample unit to measure the density of the brown mite.The brown mite has one generation with a partial second in some orchards and one with a partial second and partial third in others. The first generation adults in the bivoltine and trivoltine populations lay summer eggs on the leaves and twigs, and diapause eggs on tin twigs. The second generation adults in the bivoltine populations lay only diapause eggs; in the trivoltine populations they lay both summer and diapause eggs. The adults of the third generation lay only diapause eggs.The brown mite is found on both the leaves and woody parts of the tree. In orchards with bivoltine populations the proportion of mites on leaves reached a peak of 80% by mid-July, but thereafter gradually decreased to 10% by the end of August. However, in orchards with trivoltine populations the proportion of mites on leaves reached a peak of 80 to 90% by mid-July, remained constant until mid-August, and thereafter decreased to approximately 40% by the end of August.The number of diapause eggs laid by adults of each generation in both the bivoltine and trivoltine populations varies widely. The eggs are deposited on the trunk as well as on the branches, with the heaviest deposition in the central area of the tree. The diapause eggs laid by adults of the first generation are the last to hatch and those laid by the third generation are the first to hatch the following spring.The factors responsible for the differences in the number of generations and in the number of diapause eggs laid are unknown.


1999 ◽  
Vol 9 (4) ◽  
pp. 617-626 ◽  
Author(s):  
Guido Reifenberger ◽  
Tillmann Weber ◽  
Ruthild G. Weber ◽  
Marietta Wolter ◽  
Almuth Brandis ◽  
...  

2010 ◽  
Vol 34 (1) ◽  
pp. 169-172 ◽  
Author(s):  
Jun Wang ◽  
Chenghui Wang ◽  
Long Qian ◽  
Yuqing Ma ◽  
Xinxin Yang ◽  
...  

Author(s):  
В.И. Щуров ◽  
А.С. Замотайлов

Развитие первой генерации Corythucha arcuata в предгорьях и низкогорьях Северо-Западного Кавказа начинается в первых числах мая. При нижнем пороге пост-диапаузного развития имаго +11°С и при естественной длине дня ей требуется не менее 43 суток (аккумуляция 333-404 гр.-дн.). Гибель перезимовавших самок в этой зоне наблюдается к концу июня, совпадая с сокращением общей доли самок до 2-7%. В высокогорьях перезимовавшие имаго расселяются и в июне, доживая до июля на ивах и березах. Пик выхода имаго первого поколения приходится на конец июня. Массовая яйцекладка самками первого поколения (начало второго поколения) предваряется миграцией оплодотворенных самок на новые кормовые растения. Развитие преимагиальных стадий второго поколения (без смены кормовых растений) протекает с середины июня. Метаморфоз длится не менее 16-23 суток (361-430 гр.-дн.). Пик выхода имаго второго поколения в конце июля совпадает с массовым расселением, в котором всегда преобладают самки. Третье поколение развивается в августе. Метаморфоз занимает 19-28 суток (329-350 гр.-дн.). Пик выхода имаго третьего поколения приходится на первую декаду сентября. Его предваряет более ранний выход самцов, определяемый по их локальным и региональным миграциями с конца августа. Четвертое поколение является факультативным и развивается (без смены кормовых растений) с конца августа до третьей декады сентября. Развитие преимагиальных стадий этого поколения занимает не менее 26 суток (378 гр.-дн.). Последняя миграция клопов наблюдается в начале-середине октября. Самки третьего поколения первыми уходят в места зимовки в предгорьях и низкогорьях уже в середине сентября. Здесь, в дубовых лесах, зимуют имаго третьего и четвертого поколений обычно с преобладанием самок. В среднегорьях с ними могут зимовать особи-иммигранты второго поколения, но с преобладанием самцов, сохраняющимся с сентября. Development of the first generation of Corythucha arcuata in the climate of the foothills and lowlands of the Northwest Caucasus starts in the early May. With a natural day length and the threshold for post-diapause imago development of 11 °C, it requires 333-404 degree-days and at least 43 days. The death of the overwintered females in this zone is observed by the end of June, coinciding with the reduction of the total portion of females to 2-7%. In the highlands imagoes are dispersing in June as well, surviving until July on willows and birch trees. Peak of the first-generation imago outcome occurs at the end of June. Migration of fertilized females of the first generation to new forage plants is followed by mass egg laying (i.e. beginning of the second generation). During the formation of large nests in the foothills, the flight of bugs is observed even in treeless highlands. Development of the preadult stages of the second generation (without changing feed plants) takes place starting at mid-June. Metamorphosis requires 361-430 degree-days and takes at least 16-23 days. The peak of the emergence of the second generation imagoes at the end of July coincides with their dispersal, which is also dominated by females. The third generation develops in August. It requires 329-350 degree-days and takes 19-28 days. The peak of the emergence of the G3 imagoes falls on the first third of September. It is preceded by anearlier emergence of males, determined by their mass local and regional migrations since the end of August. The fourth generation is obligated and develops (without changing feed plants) from the end of August to the end of September. It requires at least 378 degree-days and takes at least 26 days. Late nymphs resulting from female immigrant of the third generation (on new trees) give imagoes only by mid-October. The last migration of bugs is observed in early to mid-October. Imagoes of the third and fourth generations with the predominance of females hibernate in the oak forests of the foothills and low-mountain. In the midlands they may be accompanied by the overwintering immigrants of the second generation, with the predominance of males, formed in September.


HortScience ◽  
2000 ◽  
Vol 35 (3) ◽  
pp. 416E-417
Author(s):  
Norberto Maciel ◽  
Richard A. Criley

Heliconia rostrata is a herbaceous-musoid sympodial rhizomatous plant that grows as clump. After three leaves are produced, each shoot of the clump may bear an inflorescence if it is induced by short days (SD). However, the relationship between shoot density and flowering has not been quantified. To evaluate the effects of the inductive period, number of shoots, and leaf removal on flowering, rhizomes were planted in 120 pots (8 L). One-third of the pots were planted with two rhizomes, while the remainder was planted with one. One-half of the pots with one rhizome were allowed to develop all their shoots for three generations, while in the remaining pots only one shoot per generation was allowed to grow. In addition, one-half of the plants in all the treatments were subjected to selective leaf removal. The plants were grown under long days (LD) >13 h in a glasshouse until four leaves were produced. Inductive SD was supplied to all the plants from 5:00 pm to 8:00 am. After 8 weeks of SD, one-half of the plants were given LD, while the other half continued under SD (conSD) until flowering. The highest percentage of flowering shoots (39% to 35%) was observed in plants under conSD; plants under SD-LD were 10% to 9%. The second generation of shoots showed the highest flowering (74% conSD and 21% SD-LD), followed by the first (62% conSD and 18% SD-LD), and third (31% conSD and 0% SD-LD) generations. Non-flowering shoots of the first generation were aborted or dead. Shoots of the third were still vegetative, since they had few leaves to be induced. Fewer flowers occurred in clumps allowed to develop all their shoots. Intact plants from rhizomes with one shoot per generation flowered more than the partially defoliated ones under conSD.


OENO One ◽  
2005 ◽  
Vol 39 (3) ◽  
pp. 109
Author(s):  
Emmanuel D. Ladoukakis ◽  
François Lefort ◽  
Petraq Sotiri ◽  
Arjola Bacu ◽  
Efigjeni Kongjika ◽  
...  

<p style="text-align: justify;">A recently restored ampelographic collection of Albanian grapevine accessions has been submitted to genetic profiling with eleven nuclear microsatellite markers, widely used in other studies. Microsatellite profiling resulted in 28 single profiles for 29 accessions. Two cultivars, Shesh I bardhë and Pucalla, were found to be synonyms. Genetic profiles of Albanian cultivars were compared at 8 microsatellite loci to 29 most commonly cultivated Greek cultivars. Albanian cultivars were found to be more closely related to Greek cultivars from Peloponnese. One Greek cultivar named Dempina was found to be genetically close to two Albanian cultivars Debina teki and Debina kala, which are homonyms Another cultivar, known as Toska or Sinambel displayed a tri-allelic profile at 5 loci over 10 analysed loci. Such a high number of tri-allelic loci found in one individual favours the hypothesis of triploidy but the chimerism hypothesis cannot be excluded without further work.</p>


2017 ◽  
Vol 8 ◽  
pp. 45-63 ◽  
Author(s):  
Matthias W Speidel ◽  
Malte Kleemeier ◽  
Andreas Hartwig ◽  
Klaus Rischka ◽  
Angelika Ellermann ◽  
...  

Background: Based on previous chemical analyses of insect tarsal adhesives, we prepared 12 heterogeneous synthetic emulsions mimicking the polar/non-polar principle, analysed their microscopical structure and tested their adhesive, frictional, and rheological properties. Results: The prepared emulsions varied in their consistency from solid rubber-like, over soft elastic, to fluid (watery or oily). With droplet sizes >100 nm, all the emulsions belonged to the common type of macroemulsions. The emulsions of the first generation generally showed broader droplet-size ranges compared with the second generation, especially when less defined components such as petrolatum or waxes were present in the lipophilic fraction of the first generation of emulsions. Some of the prepared emulsions showed a yield point and were Bingham fluids. Tribometric adhesion was tested via probe tack tests. Compared with the "second generation" (containing less viscous components), the "first generation" emulsions were much more adhesive (31–93 mN), a finding attributable to their highly viscous components, i.e., wax, petrolatum, gelatin and poly(vinyl alcohol). In the second generation emulsions, we attained much lower adhesivenesses, ranging between 1–18 mN. The adhesive performance was drastically reduced in the emulsions that contained albumin as the protein component or that lacked protein. Tribometric shear tests were performed at moderate normal loads. Our measured friction forces (4–93 mN in the first and 0.1–5.8 mN in the second generation emulsions) were comparatively low. Differences in shear performance were related to the chemical composition and emulsion structure. Conclusion: By varying their chemical composition, synthetic heterogeneous adhesive emulsions can be adjusted to have diverse consistencies and are able to mimic certain rheological and tribological properties of natural tarsal insect adhesives.


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