ReDivia - Repositorio Digital de l'Instit Valencià d'Investigacions Agràries
Not a member yet
2747 research outputs found
Sort by
Response of Boar Sperm to the Treatment with Cholesterol-Loaded Cyclodextrins Added Prior to Cryopreservation
No full textCryopreserved boar sperm is not used extensively for artificial insemination, owing to the poor fertility rates of the sperm after freezing and thawing. The sperm membrane is damaged as the cells are cooled from body temperature to 5 degrees C (cold shock), as well as during the freezethaw process. Increasing the cholesterol content of boar sperm membranes could help them survive cryopreservation, similar to sperm from other species that are cold shock sensitive. The aim of this study was to determine the optimal cholesterol-loaded cyclodextrin (CLC) concentration to use for boar sperm cryopreservation, and the influence of CLCs on the cryosurvival of sperm from boars classified as good or poor freezers. Treating boar sperm with 1 mg of CLC/120 x 10(6)sperm slightly improved (p < 0.05) the percentage of viable sperm after freezingthawing. On the other hand, sperm, from both good and poor freezers, responded similarly to CLC treatment. Nevertheless, additional studies will be needed to study the effect of this treatment on other parameters of sperm quality
Comparative transcriptome analysis of stylar canal cells identifies novel candidate genes implicated in the self-incompatibility response of Citrus clementina
Get PDFBackground
Reproductive biology in citrus is still poorly understood. Although in recent years several efforts have been made to study pollen-pistil interaction and self-incompatibility, little information is available about the molecular mechanisms regulating these processes. Here we report the identification of candidate genes involved in pollen-pistil interaction and self-incompatibility in clementine (Citrus clementina Hort. ex Tan.). These genes have been identified comparing the transcriptomes of laser-microdissected stylar canal cells (SCC) isolated from two genotypes differing for self-incompatibility response ('Comune', a self-incompatible cultivar and 'Monreal', a self- compatible mutation of 'Comune').
Results
The transcriptome profiling of SCC indicated that the differential regulation of few specific, mostly uncharacterized transcripts is associated with the breakdown of self-incompatibility in 'Monreal'. Among them, a novel F-box gene showed a drastic up-regulation both in laser microdissected stylar canal cells and in self-pollinated whole styles with stigmas of 'Comune' in concomitance with the arrest of pollen tube growth. Moreover, we identify a non-characterized gene family as closely associated to the self-incompatibility genetic program activated in 'Comune'. Three different aspartic-acid rich (Asp-rich) protein genes, located in tandem in the clementine genome, were over-represented in the transcriptome of 'Comune'. These genes are tightly linked to a DELLA gene, previously found to be up-regulated in the self-incompatible genotype during pollen-pistil interaction.
Conclusion
The highly specific transcriptome survey of the stylar canal cells identified novel genes which have not been previously associated with self-pollen rejection in citrus and in other plant species. Bioinformatic and transcriptional analyses suggested that the mutation leading to self-compatibility in 'Monreal' affected the expression of non-homologous genes located in a restricted genome region. Also, we hypothesize that the Asp-rich protein genes may act as Ca2+ "entrapping" proteins, potentially regulating Ca2+ homeostasis during self-pollen recognition
Effect of solid content and composition of hydroxypropyl methylcellulose-lipid edible coatings on physico-chemical and nutritional quality of 'Oronules' mandarins
Get PDFBACKGROUND: Citrus fruit represent an important source of vitamin C, as well as other bioactive compounds. Edible coatings have the potential to extend shelf life of citrus by providing a semi-permeable barrier to water and gases, which depends on coating composition, solid content (SC), and cultivar. However, little is known about the effect of coatings on citrus nutritional quality. This work studies the effect of coating composition and SC of hydroxypropyl methylcellulose (HPMC)-beeswax (BW)-shellac coatings on the physico-chemical, sensory and nutritional quality of 'Oronules' mandarins. Coatings prepared at the same lipid content differed in the BW: shellac ratio (1 : 3 and 3 : 1) and SC of the formulations (40 and 80 g kg(-1)). RESULTS: The coating with 1 : 3 BW: shellac ratio and 80 g kg(-1) SC was the most effective controlling weight loss, although it was less effective than the commercial wax tested. Increasing SC had a greater effect than the BW: shellac ratio in fruit internal atmosphere and sensory quality, with the presence of off-flavour when coatings were applied at 80 g kg(-1) SC. Nutritional quality was not affected by the application of the different treatments. CONCLUSION: HPMC-lipid coatings have the potential to extend shelf life of 'Oronules' mandarins. However, care should be taken controlling formulation SC to avoid the build-up of off-flavour. (C) 2011 Society of Chemical Industr
Evolution of chemical composition and gas emissions from aged pig slurry during outdoor storage with and without prior solid separation
Get PDFChemical composition and gas emissions from two types of pig slurry were evaluated: the liquid fraction of mechanical solid liquid separated slurry (SS), and raw slurry (RS). The slurry was obtained at the end of a pig fattening period and was stored in 1001 vessels for 15 weeks simulating outdoor storage conditions. During this period, representative samples were taken and analysed for chemical composition. Methane, carbon dioxide, ammonia, water vapour and nitrous oxide emissions were recorded. The results showed a high biological degradation during the first five weeks of outdoor storage in SS and RS slurries, as a result of an increase in the dissolved chemical oxygen demand, volatile fatty acids and carbon dioxide emission observed in this period. However, methanogenic activity was not evident until week 6 of storage in both slurries, confirmed by the volatile fatty acids accumulation and the negligible methane emissions during the first five weeks of storage. The results showed that differences in the initial slurry organic matter content, influenced by solid separation process affects the evolution pattern of the organic matter degradation. Storage time can considerably affect the biodegradability of organic matter in pig slurry
Acta Horticulturae
No full textCut flowers and pot plants are among the main dynamic, technified and socio-economic activities within the Spanish horticultural industry. Ornamental holdings concentrate along the Spanish Mediterranean coast, because of high solar radiation and mild winter conditions, that promoted greenhouse growing, resulting in high yield and quality products, suitable for satisfying the European market requirements. This work aims at analysing the present situation of the Spanish ornamental industry so as to determine the needed improvement actions in order to assure its continuity. Various statistical sources have been used, referring to both production and marketing. Technical staff and growers have been interviewed and consulted too. The technological evolution of ornamental nurseries can be known in this way. If investment in technology and equipment facilities has been the direct means in the past, for the grower to keep business profits, now adjustments of the greenhouse equipment facilities can be observed. On the other side, a lower use of some inputs is observed too, aiming at reducing costs, which could also contribute to industry sustainability. Finally, a SWOT has been built based on the observations. The main industry challenges for the future can be inferred from it, both for production and for marketing activities. One of the most important goals for the industry could be offering adaptation to a changing market demand, within a strong international competitiveness scenario. The need of actions addressed at improving promotion and appreciation of the products should also be considered. As an example of it, associating Mediterranean ornamental products as more friendly and respectful commodities with our natural environment could be an effective initiative
Effect of different monosaccharides and disaccharides on boar sperm quality after cryopreservation
No full textThe aim of the present study was to evaluate the cryoprotectant effect of different non-permeating sugars for boar sperm. Pooled semen from three boars was used for the experiments. In the first experiment, the sperm quality of boar sperm cryopreserved with an egg-yolk based extender supplemented with different monosaccharides (glucose, galactose or fructose) was compared to a control cryopreserved in lactose-egg yolk extender. In the second experiment, the effect of five disaccharides (lactose, sucrose, lactulose, trehalose or melibiose) on boar sperm cryosurvival was studied. Several sperm quality parameters were assessed by flow cytometry in samples incubated for 30 and 150 min at 37 degrees C after thawing: percentages of sperm with intact plasma membrane (SIPM), sperm presenting high plasma membrane fluidity (HPMF), sperm with intracellular reactive oxygen substances production (IROSP) and apoptotic sperm (AS). In addition, the percentages of total motile (TMS) and progressively motile sperm (PMS) were assessed at the same incubation times with a computer-assisted sperm analysis system. Freezing extenders supplemented with each of the monosaccharide presented smaller cryoprotective effect than the control extender supplemented with lactose (P < 0.05). However, from the three monosaccharides tested, glucose provided the best sperm quality after freezing-thawing. With respect to the disaccharides studied, samples frozen with the extender supplemented with lactulose exhibited in general the lowest sperm quality, except for the percentage of capacitated sperm, which was highest (P < 0.05) in the samples cryopreserved with the trehalose extender. Our results suggest that disaccharides have higher cryoprotective effect than monosaccharides, although the monosaccharide composition of the disaccharides is also important, since the best results were obtained with those disaccharides presenting glucose in their composition. (C) 2012 Elsevier B.V. All rights reserved
Histone modifications and expression of DAM6 gene in peach are modulated during bud dormancy release in a cultivar-dependent manner
No full textBud dormancy release in many woody perennial plants responds to the seasonal accumulation of chilling stimulus. MADS-box transcription factors encoded by DORMANCY ASSOCIATED MADS-box (DAM) genes in peach (Prunus persica) are implicated in this pathway, but other regulatory factors remain to be identified. In addition, the regulation of DAM gene expression is not well known at the molecular level. A microarray hybridization approach was performed to identify genes whose expression correlates with the bud dormancy-related behaviour in 10 different peach cultivars. Histone modifications in DAM6 gene were investigated by chromatin immunoprecipitation in two different cultivars. The expression of DAM4DAM6 and several genes related to abscisic acid and drought stress response correlated with the dormancy behaviour of peach cultivars. The trimethylation of histone H3 at K27 in the DAM6 promoter, coding region and the second large intron was preceded by a decrease in acetylated H3 and trimethylated H3K4 in the region of translation start, coinciding with repression of DAM6 during dormancy release. Analysis of chromatin modifications reinforced the role of epigenetic mechanisms in DAM6 regulation and bud dormancy release, and highlighted common features with the vernalization process in Arabidopsis thaliana and cereals
Flooding affects uptake and distribution of carbon and nitrogen in citrus seedlings
No full textSoil flooding has been widely reported to affect large areas of the world. In this work, we investigated the effect of waterlogging on citrus carbon and nitrogen pools and partitioning. Influence on their uptake and translocation was also studied through N-15 and C-13 labeling to provide insight into the physiological mechanisms underlying the responses. The data indicated that flooding severely reduced photosynthetic activity and affected growth and biomass partitioning. Total nitrogen content and concentration in the plant also progressively decreased throughout the course of the experiment. After 36 days of treatment, nitrogen content of flooded plants had decreased more than 2.3-fold compared to control seedlings, and reductions in nitrogen concentration ranged from 21 to 55% (in roots and leaves, respectively). Specific absorption rate and transport were also affected, leading to important changes in the distribution of this element inside the plant. Additionally, experiments involving labeled nitrogen revealed that N-15 uptake rate and accumulation were drastically decreased at the end of the experiment (93% and 54%, respectively). (CO2)-C-13 assimilation into the plant was strongly reduced by flooding, with delta C-13 reductions ranging from 22 to 37% in leaves and roots, respectively. After 36 days, the relative distribution of absorbed C-13 was also altered. Thus, C-13 recovery in flooded leaves increased compared to controls, whereas roots exhibited the opposite pattern. Interestingly, when carbohydrate partitioning was examined, the data revealed that sucrose concentration was augmented significantly in roots (37-56%), whereas starch was reduced. In leaves, a marked increase in sucrose was detected from the first sampling onwards (36-66%), and the same patter was observed for starch. Taken together, these results indicate that flooding altered carbon and nitrogen pools and partitioning in citrus. On one hand, reduced nitrogen concentration appears to be a consequence of impaired uptake and transport. On the other hand, the observed changes in carbohydrate distribution suggest that translocation from leaves to roots was reduced, leading to significant starch accumulation in leaves and further decreases in roots. (c) 2012 Elsevier GmbH. All rights reserved
Identification of simple sequence repeat markers tightly linked to plum pox virus resistance in apricot
No full textSharka disease, caused by the plum pox virus (PPV), is one of the major limiting factors for stone fruit production in Europe and America. Attempts to stop the disease through the eradication of infected trees have been unsuccessful. Introgression of PPV resistance for crop improvement is therefore the most important goal in Prunus breeding programs. Due to time- and labour-consuming protocols, phenotyping for sharka is still the major bottleneck in the breeding pipeline. In this context, screening of seedlings at early stages of development and marker-assisted selection (MAS) provide the best solution for enhancing breeding efficiency. In this study, we generated 42 simple sequence repeat (SSR) markers from the peach genome assembly v1.0 and an apricot bacterial artificial chromosome clone identified in the physical map of the PPV resistance locus previously defined in apricot. Using a linkage mapping approach, we found SSR markers tightly linked to PPV resistance trait in all our progenies. Three SSR markers, PGS1.21 PGS1.23 and PGS1.24, showed allelic variants associated with PPV resistance with no recombinants in the crosses analysed. These markers unambiguously discriminated resistant from susceptible accessions in different genetic backgrounds. The results presented here are the first successful application of their use in MAS for breeding resistance in Prunus species
Acta Horticulturae
No full textMore than twenty food additives, GRAS (Generally Regarded as Safe), and low-toxicity compounds were evaluated as nonpolluting means to control postharvest decay. The chemicals were tested at three concentrations in in vivo primary screenings with California-grown 'Flavorcrest', 'O'Henry', or 'Last Chance' peaches that had been artificially inoculated with seven major postharvest pathogens: Monilinia fructicola, Botrytis cinerea, Geotrichum candidum, Alternaria alternata, Penicillium expansum, Mucor piriformis, and Rhizopus stolonifer. Overall, the best compounds were potassium sorbate, sodium benzoate, and sodium sorbate at 200 mM, 2-deoxy-D-glucose at 100 mM, sodium carbonate at 400 mM, and potassium carbonate at 250 mM. Sodium and ammonium molybdates, acid lactic, and hydrogen peroxide were somewhat effective but phytotoxic to fruit skin tissues. The selected compounds, however, lacked effectiveness and persistence when tested against brown rot, caused by M. fructicola, in small-scale trials as 60 s dips in aqueous solutions at ambient temperatures. Heating the solutions to 55 or 60 degrees C significantly increased treatment efficacy and brown rot incidence and severity were reduced by 35 and 25%, respectively, after 7 days of incubation at 20 degrees C on peaches treated with potassium sorbate. However, treatment efficacy was not superior to water alone at these temperatures. Therefore, the potential for use of common food additives or GRAS compounds as alternative chemicals to conventional fungicides for the control of brown rot of California peaches is rather limited and heat treatments appear more suitable than these chemicals to be combined with other environmentally-friendly antifungal treatments for integrated disease control. The control by these means of other important peach postharvest diseases such as gray mold and sour rot, caused by B. cinerea and G. candidum, respectively, deserves further study