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Role of Embryonic and Maternal Genotype on Prenatal Survival and Foetal Growth in Rabbit
No full textContents The aim of this work was to evaluate the influence of maternal and embryonic genotype on prenatal survival and foetal growth during pregnancy. Embryos were recovered at 48h of gestation from two different donor lines (R=46 and A=40) and transferred to nulliparous recipient does (26 R and 24 A). Each recipient doe received six embryos into one oviduct from line R, and six embryos form line A into the other. Laparoscopy was performed at Day 14 to determine implantation rate. Recipient females were slaughter at Days 14, 24 and 30 (12, 24, and 14, respectively) to determine the number of live foetuses and the weight of live foetuses, foetal placenta and maternal placenta. A transcriptome analysis was performed to search for differences between foetal placentas at Days 14 and 24 of development. Prenatal survival at Days 14, and 24 was affected by embryonic genotype and determined by maternal genotype at Day 30. Foetal weight at Day 14 was influenced by both genotypes, being the weight higher for group A/A (0.29 +/- 0.01g vs 0.19 +/- 0.01g, for group R/R). However, both genotypes were determinant for foetal placenta weight at Day 24, while those genotypes affected maternal placenta weight at Day 30. Nevertheless, no differences in foetal placenta at transcriptome level and progesterone and IGF-I plasma levels in recipient does were found. In conclusion, results indicate that the influence of embryo and maternal genotype on the prenatal survival and growth seems to be changing over gestation
Defensive plant responses induced by Nesidiocoris tenuis (Hemiptera: Miridae) on tomato plants
Get PDFIn the last decade, biological control programs for greenhouse tomatoes and other crops have been successfully implemented using zoophytophagous plant bugs (Miridae), which can feed on both plant tissues and insect prey. It is well known that plants respond to herbivore attacks by releasing volatile compounds through diverse pathways triggered by phytohormones. These herbivore-induced plant volatiles can alert neighboring plants, repel or attract herbivores, and attract natural enemies of these herbivores. Nevertheless, the possible benefits of induced plant responses by zoophytophagous predators that could add to their usefulness as biocontrol agents have not been studied until now. Here we show that the zoophytophagous predator Nesidiocoris tenuis activated abscisic acid and jasmonic acid (JA) signaling pathways in tomato plants, which made them less attractive to the whitefly Bemisia tabaci, a major tomato pest worldwide, and more attractive to the whitefly parasitoid, Encarsia formosa. We also found that intact tomato plants exposed to volatiles from N. tenuis-punctured plants activated the JA pathway, and as a consequence, E. formosa was also attracted to these intact plants with activated defense systems. Thus, our results demonstrate that N. tenuis not only benefits tomato plants directly by entomophagy but also indirectly by phytophagy, which induces a physiological response in the tomato plant
Acta Horticulturae
Get PDFWhile the molecular response of model plants to salt stress in the short-medium term (hours-days) has been broadly studied, the knowledge about the nature of genes involved in maintaining homeostatic conditions in the long term (months-years) in woody perennial trees has not been addressed yet. We have analyzed physiological parameters and the transcriptome profiles of photosynthetically active leaves from citrus trees acclimatized to moderate salinity (NaCl 30 mM) after 2 years treatment. Through functional genomics, global gene expression in response to NaCl treatment in mature (8 months-old) and young (2 months-old) leaves has been analyzed and compared. Although young leaves (YL) accumulated low levels of chloride (0.51%+/- 0.06), they exhibited a much stronger response to salinity in term of the number of differentially expressed genes (1,211 genes) compared with mature leaves (ML), which accumulated higher chloride levels (1.05%+/- 0.01), and exhibited a much lower number of differentially-responsive genes (100 genes). In this work, a number of responses have been observed that differ from those described in previous studies of citrus plants non-acclimatized to salt stress (Brumos et al., 2009), whose principal manifestation was the lack of repression of primary metabolism in leaves at the molecular and physiological levels. Results describing enriched functional categories of differentially expressed genes are presented and discussed highlighting how the long-term acclimation to NaCl stress involves drastically different molecular strategies depending on the developmental stage of plant leaves
Effect of genistein added to bull semen after thawing on pronuclear and sperm quality
No full textThe aim of this research was to study the effect of different genistein treatments on bull sperm after thawing on pronuclear formation after in vitro fertilization (IVF) and on different sperm quality variables. Three experiments were performed. In Experiment 1, three treatments (Control, sperm incubation for 1 h at 37 degrees C with or without genistein) and two sperm concentrations during IVF (I or 3 x 10(6) sperm/mL) were evaluated to study the influence of genistein on pronuclear formation (PNF). Sperm incubation for 1 h before IVF reduced PNF regardless of sperm concentration. However, after sperm incubation and with 3 x 10(6) sperm/mL in IVF, the genistein treatment group had greater fertilization rates than the untreated group. In Experiment 2, six treatments plus the control group were performed to study the effect of genistein (presence or not) and incubation conditions (30 min at 37 degrees C, 1 h at 27 degrees C or at 37 degrees C) on PNF using 3 x 10(6) sperm/mL for IVF. When incubation time was reduced to 30 min, PNF rate from the genistein treatment group was no different from either the control group or in the group in which incubation occurred for 1 h at 27 degrees C. In Experiment 3, the effect of several genistein treatments (control; genistein treatment for 30 min of incubation at 37 degrees C; genistein treatment for 1 h of incubation at 27 degrees C) on sperm motility, viability and DNA fragmentation were evaluated. Genistein did not improve sperm motility and, depending on the experimental group or time, it either reduced or had no effect on sperm motility. Genistein treatment did not improve sperm viability after 5 h of incubation. However, genistein treatment for 1 h at 27 degrees C decreased sperm DNA fragmentation compared with the control group after 5 h of sperm incubation. In conclusion, the treatment of bull sperm with genistein for 1 h at 27 degrees C could decrease sperm DNA fragmentation, although PNF rate after IVF and sperm motility were reduced
Effect of the pH pre-adjustment in the freezing extender on post-thaw boar sperm quality
No full textBackground: During freezing the selective precipitation of substances in the medium may
provoke a pH shift and lead to sperm damage. Objective: To study the effect of the pH preadjustment in the freezing extender on post-thaw boar sperm quality. Methods: A total of 15
ejaculates from different boars were obtained and divided into six aliquots prior to a standard straw
cryopreservation in freezing extender (lactose-egg yolk-glycerol-Orvus ES Paste) with different pH.
After thawing, sperm quality (plasma membrane integrity, motility and acrosome status) were assessed
at 30 and 90 minutes of post-thaw incubation at 37ºC.
Results: When the boar sperm were frozen
in a freezing media with pH basic, and particularly at pH 8, it had higher post-thaw sperm quality.
Conclusion: The pre-adjustment at pH 8 of the freezing extender (lactose-egg yolk-glycerol-Orvus
ES Paste) is able to improve the post-thaw boar sperm quality
Acta Horticulturae
No full textSpain is the largest citrus producer within the European Union and the fifth worldwide with an average production of 5 million tons per season. Most of it is exported to third countries. Indeed, according to FAO, Spain is considered the first citrus exporter worldwide. Spanish citrus production is mainly destined to fresh market. Due to the high fruit quality standards demanded by this market, citrus pest management has to provide fruit with almost no pest presence or damage and at the same time, with minimal pesticide residues. International market demands place Spanish citrus industry in an unbeatable position to implement area-wide Integrate Pest Management (aw-IPM) programs. In the last years the citrus producing area that adopted IPM programs has dramatically increased. In 2012 more than 19% of the production already followed IPM regulations and that was a 5-fold increment relative to 2005. The current trend indicates that the number of growers adopting IPM systems will keep increasing over the coming years. The present article summarizes the current status of Spanish citrus IPM, how pests are hierarchized according to their biological control and which are the available IPM tools for growers. Large scale implementation of this management approach will permit Spanish citrus production to make a qualitative leap in a society that seeks for healthier eating habits and more environmental friendly production systems
A single natural nucleotide mutation alters bacterial pathogen host tropism
No full textThe capacity of microbial pathogens to alter their host tropism leading to epidemics in distinct host species populations is a global public and veterinary health concern. To investigate the molecular basis of a bacterial host-switching event in a tractable host species, we traced the evolutionary trajectory of the common rabbit clone of Staphylococcus aureus. We report that it evolved through a likely human-to-rabbit host jump over 40 years ago and that only a single naturally occurring nucleotide mutation was required and sufficient to convert a human-specific S. aureus strain into one that could infect rabbits. Related mutations were identified at the same locus in other rabbit strains of distinct clonal origin, consistent with convergent evolution. This first report of a single mutation that was sufficient to alter the host tropism of a microorganism during its evolution highlights the capacity of some pathogens to readily expand into new host species populations
Acta Horticulturae
No full textCitrus cultivars must meet two basic conditions for fresh consumption: i) they should cover the widest possible commercial calendar, and ii) allow continuous adaptation to consumer preferences. For citrus growers, this requires permanent adoption of new technology and changes in the cultivars grown, driven by income-risk criteria, as well as by technical and commercial experience. The duration of an investment depends on the agronomic performance of the cultivar or its commercial life, which may be shortened due to lack of consumer acceptance. The survival of a cultivar depends on many variables: technical, quality, and competitiveness of the cultivar. Spanish citrus production falls into five main groups of cultivars: lemons (10.8%), clementines (25%), mandarin hybrids (8.7%), navel oranges (35%) and common oranges (15%). The most productive cultivars are ‘Fino’ lemon, ‘Navelina’ navel, ‘Clemenules’, ‘Lane Late’ navel and ‘Valencia’ sweet orange. In relation to changes in varietal composition, it is of interest the introduction of new cultivars of the clemenules group (‘Orogrande’, ‘Nulessin’), navel (‘Powell’, ‘Rohde’, ‘Barnfield’, ‘Chislett’ and ‘Fukumoto’) and Valencia (‘Barberina’, ‘Midknight’, ‘Valencia Late’ Frost and ‘Delta Seedless’). There is constant pressure to supply new early clementines cultivars, but their survival is usually short. Currently, mandarin hybrids represent a group with a strong potential to expand
Efecto de la temperatura sobre la respiración de los órganos reproductivos y vegetativos del limón
Get PDFSe recogieron muestras de flores y frutos de limón y se clasificaron según su
estado fenológico. También se recogieron muestras de hoja, corteza y raíz siendo
clasificados en distintos estados según su etapa de crecimiento. La respiración de las
muestras se midió cuantificando el CO2 desprendido mediante cromatografía de
gases. Con el fin de cubrir las distintas condiciones térmicas típicas de la zona, el
ensayo se realizó a 15, 25 y 35ºC. Los resultados mostraron que el primer estado de
las flores, botón floral, fue el que manifestó los mayores valores de respiración. Con
respecto a los frutos, se hizo visible una reducción de la respiración al verse
incrementado el estado de maduración de estos. En cuanto a los órganos vegetativos,
los mayores valores de respiración se observaron en las hojas de los brotes nuevos,
seguido de la corteza y por último de las raíces. Tanto en los órganos reproductivos
como en los vegetativos se observó un incremento significativo de la respiración al
aumentar la temperatura
Acta Horticulturae
No full textCitrus is an economically important world tree fruit crop with production in more than 146 countries. The center of origin for citrus is considered to be Southeastern Asia including southern China, northeastern India, and Malaysia, with secondary centers in surrounding areas. Novel and commercially significant scion and rootstock cultivars originating by natural mutation or directed hybridization were introduced during the past century. Significant genetic resource collections exist in many countries. A global citrus germplasm network was developed in 1997. Now that the International Treaty on Plant Genetic Resources for Food and Agriculture (ITPGR) has recognized Citrus as an Annex 1 crop, a global conservation strategy needs to be established. The objective of this workshop was to plan the development of this strategy. More than 60 delegates attended with representation from Argentina, Australia, Bhutan, Brazil, China, Columbia, France, Iran, Israel, Italy, Japan, Mexico, Morocco, Portugal, Spain, Turkey, UAE, US, and Vietnam. Nine oral presentations were given describing multiple aspects of genebank operations, technologies and gaps in Brazil, China, France, Australia, Spain, and the US. A draft genebank survey questionnaire was presented to the group and comments and suggested changes for improvement were received. Citrus curators and genebank managers throughout the world will be surveyed for the status and health of their collections. The surveys will be received and compiled by collaborators at the University of California, Riverside, and at the USDA ARS Riverside. This information will be compiled and reported. The strategy will include background and history of the development of Citrus as a cultivated crop, conservation protocols, vulnerabilities, and recommendations for safeguarding Citrus germplasm. This strategy will be implemented through the Global Crop Diversity Trust with collaboration from the International Society for Horticultural Science and the international Citrus research community