A mysterious parthenogenetic cambarid crayfish (the Marmorkrebs) has been spreading across the globe for the past decade. We compare this crayfish directly to two other cambarids, Procambarus fallax and P. alleni, that have been suggested to be related or even identical to the Marmorkrebs. Using external morphology and sequences of two mitochondrial genes we show clear correspondences between M...

because of limitations of production of unicellular green algae (especially in large volumes), this study aimed to culture artemia using three sources of cheap agricultural by-products that were coupled with small amounts of unicellular algae dunaliella salina. the results of growth and survival, biomass production, individual wet weight, wet and ash percent, fcr and sgr and nutritional value o...

Parthenogenetic embryos are an ethically acceptable alternative for the derivation of human embryonic stem cells. In this work, we propose a new strategy to produce bovine parthenogenetic embryos inhibiting the emission of the first polar body during in vitro maturation, and allowing the extrusion of the second polar body during oocyte activation. Cytochalasin B, an inhibitor of actin microfila...

The parthenogenetic snail Melanoides tuberculata, present in tropical fresh waters of most of the Old World before 1950, has now invaded the Neotropical area. The phylogeography of this snail was studied to evaluate the pathways and number of such invasions. Because of parthenogenetic reproduction, individuals are structured into genetical clones. Within populations from both the original and i...

To investigate the mode of inheritance of apomixis in Chinese chive, the degrees of diplospory and parthenogenesis were evaluated in F(1) and BC(1) progenies derived from crosses between amphimictic and apomictic diploids (2n = 16, 2x). The F(1) population was generated by crossing three amphimictic diploids 94Mo13, 94Mo49 and 94Mo50 with an apomictic diploid KaD2 and comprised 110 diploids and...

Cloned mouse embryos display a marked preference for glucose-containing culture medium, with enhanced development to the blastocyst stage in glucose-containing medium attributable mainly to an early beneficial effect during the first cell cycle. This early beneficial effect of glucose is not displayed by parthenogenetic, fertilized, or tetraploid nuclear transfer control embryos, indicating tha...

External morphology of second-stage juveniles of six populations of Meloidogyne hapla, hclonging to two cytological races (A and B), and one population each of M. arenaria, M. incognita, and M. javanica was compared by scanning electron microscopy (SEM). Race A of M. hapla included three facultatively parthenogenetic populations with haploid chromosome numbers of 15. 16, and 17; race B consiste...

HE success of BLAKESLEE and AVERY (1937) and of NEBEL and T RUTTLE (1938) in inducing polyploidy in plants by means of colchicine treatments has been followed by investigations of other plant materials by a number of workers (EIGSTI 1938, WALKER 1938, DERMEN 1939, LEVAN 1938, and RASMUSSON and LEVAN 1939). While polyploid plants have been obtained by treating diploid plants with colchicine, app...

Embryonic stem (ES) cells derived from mammalian embryos have the ability to form any terminally differentiated cell of the body. We herein describe production of parthenogenetic buffalo (Bubalus Bubalis) blastocysts and subsequent isolation of an ES cell line. Established parthenogenetic ES (PGES) cells exhibited diploid karyotype and high telomerase activity. PGES cells showed remarkable long...

Ecotoxicological tests are increasingly being used to evaluate the toxicity of a substance or mixture of substances towards soil fauna. One of these uses the parthenogenetic collembolan Folsomia candida to test for soil contamination, and this has been standardised in Europe. However, in such studies, it is important to know whether different laboratories use genetically close clones. In this s...