Search results for "N fertilization"
showing 10 items of 114 documents
Nutrient removal by rice–wheat cropping system as influenced by crop establishment techniques and fertilization options in conjunction with microbial…
2020
AbstractNutrient uptake by the rice–wheat cropping system (RWCS) is an important indicator of soil fertility and plant nutrient status. The hypothesis of this investigation was that the rate and sources of nutrient application can differentially influence nutrient removal and soil nutrient status in different crop establishment techniques (CETs). Cropping system yield was on par in all the CETs evaluated, however, there were significant changes in soil nutrient availability and microbiological aspects. The system nitrogen (N), phosphorus (P), potassium (K) and zinc (Zn) uptake in aerobic rice system followed by zero tillage wheat (ARS-ZTW) was 15.7–17.6 kg ha−1, 0.7–0.9 kg ha−1, 7–9.8 kg ha…
Structure of mammalian plasma fetuin-B and its mechanism of selective metallopeptidase inhibition
2018
The co-crystal structure of the metallopeptidase astacin with its specific protein inhibitor fetuin-B reveals a novel mechanism of inhibition.
Regulation of Macromolecular Synthesis during Sea Urchin Development
1979
Immediately following fertilization the sea urchin egg enters a period of very rapid cell division that cleaves the egg cell into about one thousand proportionately smaller cells, which form the swimming blastula, i.e. a larval form that is less vulnerable to environmental injuries since it is capable of actively swimming away from them.
Effects of nitrogen enrichment on zooplankton biomass and N:P recycling ratios across a DOC gradient in northern-latitude lakes
2021
AbstractWe used data from whole-lake studies to assess how changes in food quantity (phytoplankton biomass) and quality (phytoplankton community composition, seston C:P and N:P) with N fertilization affect zooplankton biomass, community composition and C:N:P stoichiometry, and their N:P recycling ratio along a gradient in lake DOC concentrations. We found that despite major differences in phytoplankton biomass with DOC (unimodal distributions, especially with N fertilization), no major differences in zooplankton biomass were detectable. Instead, phytoplankton to zooplankton biomass ratios were high, especially at intermediate DOC and after N fertilization, implying low trophic transfer effi…
Sea urchin embryos as an in vivo model for the assessment of manganese toxicity: developmental and stress response effects.
2009
In the marine environment increasing concentrations of bio-available compounds often result from anthropogenic activities. Among metal ions, manganese represents a new emergent factor in environmental contamination. Here, we studied the effects of manganese on Paracentrotus lividus sea urchin embryos using biological and biochemical approaches for the analysis of impact on development, tissue accumulation and stress markers. Embryos were continuously exposed from fertilization to manganese at concentrations ranging from 1.0 to 61.6 mg l(-1), monitored for developmental abnormalities at 48 h after fertilization, and used for atomic spectrometric analysis at various times from 6 to 72 h. We f…
Predictive variables of in vitro fertilization and pre-implantation embryo development in the mouse
2002
The present study aims to analyze the cause-effect relationships among several in-vitro fertilization and pre-implantation embryo development variables in the mouse. Superovulation of hybrid (C57Bl/6JIco female X CBA/JIco male) female mice of 4-6 weeks of age was induced by a priming injection of pregnant mare's serum gonadotropin at the estrus stage of the estrous cycle followed after a 48-hr interval by human chrorionic gonadotropin. Ovulated cumulus-enclosed oocytes were inseminated with sperm from hybrid males of 12-16 weeks of age. The multiple linear regression analyses performed indicated that (a) total number of ovulated oocytes is a good predictor of both fertilization frequency an…
Stage of the estrous cycle at the time of pregnant mare's serum gonadotropin injection affects pre-implantation embryo development in vitro in the mo…
2002
The present study aims to analyze in the mouse the effect of the stage of the estrous cycle at the time of pregnant mare's serum gonadotropin (PMSG) injection on fertilization of ovulated cumulus-enclosed oocytes and later embryo development in vitro to the blastocyst stage. Quality of blastocysts was evaluated by staining and counting of total number of nuclei, mitotic index, percentage of apoptotic nuclei, and cell allocation to the inner cell mass (ICM) and trophectoderm (TE) lineage. Superovulation of hybrid (C57Bl/6JIco female x CBA/JIco male) female mice of 4-6 weeks of age was induced by a priming injection of PMSG at different stages of the estrous cycle followed after a 48-hr inter…
Precision Oliviculture: Research Topics, Challenges, and Opportunities—A Review
2022
Since the beginning of the 21st century, there has been an increase in the agricultural area devoted to olive growing and in the consumption of extra virgin olive oil (EVOO). The continuous change in cultivation techniques implemented poses new challenges to ensure environmental and economic sustainability. In this context, precision oliviculture (PO) is having an increasing scientific interest and impact on the sector. Its implementation depends on various technological developments: sensors for local and remote crop monitoring, global navigation satellite system (GNSS), equipment and machinery to perform site-specific management through variable rate application (VRA), implementation of g…
Effect of the Bovine Oviductal Fluid onIn VitroFertilization, Development and Gene Expression ofIn Vitro-Produced Bovine Blastocysts
2012
Oviductal microenvironment generally provides better condi-tions for early embryo development than the conventionalin vitro system. In an attempt to simulate the oviductconditions or the main potentially influencing factors, theeffect was studied of a bovine oviductal fluid (bOF) treatmentapplied prior to IVF on (i) IVF parameters, (ii) cleavage rate,(iii) blastocyst yield and (iv) blastocyst quality. Embryo qualitywas assessed by morphological embryo quality and relativetranscript abundance of several developmental genes in bovineblastocysts. Furthermore, to study the effect of bOF withoutthe male effect and zona–sperm interaction, artificially acti-vated metaphase II oocytes were also treated w…
O-115 Parental whole-exome sequencing allows the discovery of genetic causes of extreme IVF phenotypes such as oocyte/embryo developmental arrest and…
2021
Abstract Study question Do whole-exome sequencing (WES) data from infertile women provide valuable information for the discovery of genes/pathways involved in extreme IVF phenotypes, i.e. oocyte/embryo developmental arrest? Summary answer The development of a specific bioinformatic WES pipeline revealed known and new candidate genes/pathways for isolated oocyte/embryo developmental failure,providing the foundation to scale up research. What is known already The use of IVF has made it possible to identify extreme and isolated infertility phenotypes such as recurrent low oocytes maturity (LMR), recurrent low fertilization rate (LFR), or preimplantation developmental arrest (PDA) that would re…