PREPARACIÓN DE TOROS MARCADORES

Different methodologies for the preparation of marker bulls are described, such as fixing the sigmoid bend of the penis, artificial phimosis, lateral implant of the prepuce in Zebu bulls, resection of the apical dorsal ligament of the penis, fixation of the penis, epididymectomy, and overlap technique and surgical deviation with tunneling, concluding that the success or failure in the preparation of a marker bull depends more on the knowledge of the surgical technique and the postsurgery management than on the technique applied.Se describen diferentes metodologías para la preparación de toros marcadores, tales como, fijación de la flexura sigmoidea del pene, fimosis artificial, implantación lateral del prepucio en toros cebuínos, resección del ligamento apical dorsal del pene, fijación del pene, epididimectomía, técnica de traslape y desviación quirúrgica con tunelización, concluyendo que el éxito o fracaso en la preparación de un toro marcador, depende más del conocimiento de la técnica quirúrgica y del manejo posoperatorio que de la técnica aplicada

Natural selection on cork oak: allele frequency reveals divergent selection in cork oak populations along a temperature cline

A recent study of population divergence at neutral markers and adaptive traits in cork oak has observed an association between genetic distances at locus QpZAG46 and genetic distances for leaf size and growth. In that study it was proposed that certain loci could be linked to genes encoding for adaptive traits in cork oak and, thus, could be used in adaptation studies. In order to investigate this hypothesis, here we (1) looked for associations between molecular markers and a set of adaptive traits in cork oak, and (2) explored the effects of the climate on among-population patterns in adaptive traits and molecular markers. For this purpose, we chose 9-year-old plants originating from thirteen populations spanning a broad range of climatic conditions. Plants established in a common garden site were genotyped at six nuclear microsatellites and phenotypically characterized for six functional traits potentially related to plant performance. Our results supported the proposed linkage between locus QpZAG46 and genes encoding for leaf size and growth. Temperature caused adaptive population divergence in leaf size and growth, which was expressed as differences in the frequencies of the alleles at locus QpZAG46

Genomic signatures of local adaptation reveal source-sink dynamics in a high gene flow fish species

Understanding source-sink dynamics is important for conservation management, particularly when climatic events alter species' distributions. Following a 2011 'marine heatwave' in Western Australia, we observed high recruitment of the endemic fisheries target species Choerodon rubescens, towards the cooler (southern) end of its distribution. Here, we use a genome wide set of 14 559 single-nucleotide polymorphisms (SNPs) to identify the likely source population for this recruitment event. Most loci (76%) showed low genetic divergence across the species' range, indicating high levels of gene flow and confirming previous findings using neutral microsatellite markers. However, a small proportion of loci showed strong patterns of differentiation and exhibited patterns of population structure consistent with local adaptation. Clustering analyses based on these outlier loci indicated that recruits at the southern end of C. rubescens' range originated 400 km to the north, at the centre of the species' range, where average temperatures are up to 3 °C warmer. Survival of these recruits may be low because they carry alleles adapted to an environment different to the one they now reside in, but their survival is key to establishing locally adapted populations at and beyond the range edge as water temperatures increase with climate change

Rapid transcriptional plasticity of duplicated gene clusters enables a clonally reproducing aphid to colonise diverse plant species

Background: The prevailing paradigm of host-parasite evolution is that arms races lead to increasing specialisation via genetic adaptation. Insect herbivores are no exception and the majority have evolved to colonise a small number of closely related host species. Remarkably, the green peach aphid, Myzus persicae, colonises plant species across 40 families and single M. persicae clonal lineages can colonise distantly related plants. This remarkable ability makes M. persicae a highly destructive pest of many important crop species. Results: To investigate the exceptional phenotypic plasticity of M. persicae, we sequenced the M. persicae genome and assessed how one clonal lineage responds to host plant species of different families. We show that genetically identical individuals are able to colonise distantly related host species through the differential regulation of genes belonging to aphid-expanded gene families. Multigene clusters collectively upregulate in single aphids within two days upon host switch. Furthermore, we demonstrate the functional significance of this rapid transcriptional change using RNA interference (RNAi)-mediated knock-down of genes belonging to the cathepsin B gene family. Knock-down of cathepsin B genes reduced aphid fitness, but only on the host that induced upregulation of these genes. Conclusions: Previous research has focused on the role of genetic adaptation of parasites to their hosts. Here we show that the generalist aphid pest M. persicae is able to colonise diverse host plant species in the absence of genetic specialisation. This is achieved through rapid transcriptional plasticity of genes that have duplicated during aphid evolution

A Widespread Chromosomal Inversion Polymorphism Contributes to a Major Life-History Transition, Local Adaptation, and Reproductive Isolation

A set of experiments demonstrates the involvement of a chromosomal inversion in the adaptive transition between annual and perennial ecotypes of the yellow monkeyflower, Mimulus guttatu

Wstępna ocena krzewów i owoców wisienki kosmatej (Prunus tomentosa Thunb.) z rozmnożenia generatywnego

W pracy przedstawiono wyniki plonowania wybranych krzewów wisienki kosmatej, które rozmnożono z nasion otrzymanych z Akademii Rolniczej w Gorki ( Białoruś). Otrzymane z nasion siewki wysadzono w ogrodzie doświadczalnym ART w Olsztynie. Z całej populacji wysadzonych 50 krzewów wybrano do badań 7. Charakteryzowały się one najlepszym plonowaniem i jakością owoców. W badaniach oceniano wielkość plonu, wielkość owoców oraz skład chemiczny na zawartość podstawowych składników organicznych. Stwierdzono, że w warunkach Olsztyna można z powodzeniem uprawiać wisienkę kosmatą. Poszczególne wybrane krzewy różniły się między sobą wielkością owoców i pestki, a także zawartością suchej masy w owocach i ilością cukrowców.Yields of chosen villous cherry bushes were presented. The bushes were propagated from seeds obtained at the Academy of Agriculture in Gorki (Belorussia). The seedlings obtained were set out in the Experimental Garden at the University of Agriculture and Technology in Olsztyn. From among the population of 50 bushes planted, 7 bushes were tested. They were characterized by the highest fruit yield and quality. Yield size and chemical composition of the fruits were determined. It was found that under the conditions of Olsztyn area the villous cherry may be grown successfully. The bushes differed among themselves in fruit and stone size, in the content of fruit dry matter and the amount of sugars