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Year 2010 marks a centennial anniversary of the description by Stella Starkel and Les³aw Wêgrzynowski, Polishstudents of the Faculty of Medicine, University of Lwów, the fetal zone of the human fetal adrenal gland. In 1911 both, Starkeland Wêgrzynowski were graduated from the Faculty of Medicine of Lwow University. The paper appeared in the German Arch.Anat. Physiol. and its original title was "Beitrag zur Histologie der Nebeniere bei Feten und Kindern“ ("Contribution to histologyof adrenals of fetuses and children"). The studies were performed on 100 adrenal glands obtained from fetuses (from6th month of gestation) and up to 5-year-old children. They described the fetal zone as a "medullary zone”, also as "immaturecortex", which undergoes involution in first years of life. To commemorate this discovery, this review aimed to present the mostimportant achievements of studies on the development and involution of the human adrenal fetal zone.

High costs of manual pruning and lack of skilled workers incline fruit growers to mechanical pruning. Mechanical pruning gives good results in the case of trees that do not require selective pruning, like citrus trees. This pruning method is also acceptable if the fruit is produced for industrial purposes. Twelve-year-old ‘Pinova’ apple trees grafted on dwarf M.9 rootstocks, spaced at 4 × 1.5 m, trained to the spindle system were mechanically pruned at the pink flower stage (first week of May) and at the fruit setting stage (first week of June). The pruning was done with a STIHL cutting bar as ‘topping’ (trimming the tops of trees) and ‘hedging’ – pruning of trees from two sides at an angle of 70°. Before the pruning, the trees had a height of 3.5 m and over 2.0 m spread at the bottom part of tree canopy. Control trees were pruned manually using standard methods. The height of the trees was reduced with mechanical and manual pruning to 2.5 m, and the spread to 2 m at the base of tree canopy. During the three years of the trial, mechanical pruning significantly altered the canopy structure. It developed into a continuous, compact wall without any openings along the row. In the same time, hand pruned trees had free openings in the upper part of tree canopies. Mechanically pruned trees had lower solar irradiation levels than manually pruned trees. In the third year, the trees pruned mechanically gave higher yields than the trees pruned manually, but fruit size, mean fruit weight and the area of the red blush were significantly decreased. The trial indicated that mechanical pruning of apple trees must be supplemented by hand pruning. More attention is also needed to fruit thinning when trees are pruned mechanically.

Current concepts of growth hydraulics in higher plants are critically revisited, and it is concluded that they partly fail to interpret the experimental data adequately, particularly in the case of hydroponics-grown roots. Theoretical considerations indicate that the growth rate in roots is controlled by the extensibility of the cell wall, excluding water availability (i.e. hydraulic conductance) as a major constraint. This is supported by the findings that the growth rate does not scale with turgor, and that no radial nor axial water potential gradients have been observed in the root elongation zone. Nevertheless, a water potential deficit ranging from --0.2 to --0.6 MPa has repeatedly been reported for growing cells that by far exceeds the shallow trans-membrane water potential difference required for the uptake of growth water. Unexpectedly, growth was also shown to depend on the hydraulic conductance (LP) of the plasma membrane of root cells, even though LP should generally be too large to have an impact on growth. For leaves, similar observations have been reported, but the interpretation of the data is less straightforward. Inconsistencies associated with the current model of growth hydraulics prompt the author to suggest a revised model that comprises, in addition to a passive mechanism of water transport across the plasma membrane of growing cells mediated by aquaporins ('leak') a secondary active water transport ('pump'), in analogy to a mechanism previously demonstrated for mammalian epithelia and postulated for xylem parenchyma cells in roots. Water is hypothesised to be secreted against a trans-membrane water potential difference by cotransport with solutes (salts, sugars, and/or amino acids), taking advantage of the free energy released by this transport step. The solute concentration gradient is supposed to be maintained by a subsequent retrieval of the solutes from the apoplast and backtransport at the expense of metabolic energy. Water secretion tends to reduce the turgor pressure and retards growth, but turgor and, in turn, growth can be upregulated very rapidly independent from any adjustment in the osmolyte deposition rate by increasing LP and/or reducing secondary active water transport, e.g. when the root is exposed to mild osmotic stress, as confirmed by experimental studies. [ABSTRACT FROM AUTHOR]

Redox reactions affecting the cell wall extensibility proceed in the apoplast of growing cells. The reactions involve dozens of oxidoreductases localized in cell walls (Class I and III heme peroxidases, FAD- and Cu-dependent amine oxidases, oxalate oxidase, ascorbate oxidase, superoxide dismutase, etc.) together with NADPH oxidase and quinone reductase of the plasma membrane. The cell wall extensibility decreases due to peroxidase-catalyzed phenolic cross-links of polymers. Cell growth is proven to be directly dependent on production of reactive oxygen species (ROS) in the apoplast. A special value is attached to hydroxyl radical OH•, which is able to locally cleave polysaccharides and, thus, increase wall extensibility. Generation of OH• results from one-electron reduction of HO and, consequently, is related to the complex of enzymatic and spontaneous reactions of HO turnover in the apoplast. The extensibility also depends on an ascorbate concentration in the apoplast and on a ratio of its oxidized to reduced forms. This dependence is expressed not only in the well-known down-regulation of phenols oxidation but also through pro-oxidant and signal activities. There is only indirect evidence of a role of apoplast-originated redox signaling in the cell growth regulation. In addition to ascorbate, the signaling may supposedly involve ROS, glutathione recycling reactions, numerous redox-sensitive peptides, and proteins localized in the cell wall and the plasma membrane. [ABSTRACT FROM AUTHOR]

Plant polyamines are catabolized by two classes of amine oxidases, the copper amine oxidases (CuAOs) and the flavin adenine dinucleotide (FAD)-dependent polyamine oxidases (PAOs). These enzymes differ to each other in substrate specificity, catalytic mechanism and subcellular localization. CuAOs and PAOs contribute to several physiological processes both through the control of polyamine homeostasis and as sources of biologically-active reaction products. CuAOs and PAOs have been found at high level in the cell-wall of several species belonging to Fabaceae and Poaceae families, respectively, especially in tissues fated to undertake extensive wall loosening/stiffening events and/or in cells undergoing programmed cell death (PCD). Apoplastic CuAOs and PAOs have been shown to play a key role as a source of H2O2 in light- or developmentally-regulated differentiation events, thus influencing cell-wall architecture and maturation as well as PCD. Moreover, growing evidence suggests a key role of intracellular CuAOs and PAOs in several facets of plant development. Here, we discuss recent advances in understanding the contribution of different CuAOs/PAOs, as well as their cross-talk with different intracellular and apoplastic metabolic pathways, in tissue differentiation and organ development. [ABSTRACT FROM AUTHOR]

Aqueous extract from leaves of Sambcus ebulus L. were tested for antifeedant, growth regulation and ovicidal effects against the red floor beetle Tribolium confusum Duv. under laboratory condition (29?1?C, RH 60?5% and 12L:12D). The results indicated a significant deterrence for feeding, and comparatively significant larval, pupal and adult weight decrease in treated vs. controlled insects. Similarly the ovicidal effect of the extract was significant, thus reducing the number of F1 generation of resulting adults.

Tetradecylthioacetic acid (T11111141), which cannot be β-oxidized, exerts growth-limiting properties in glioma cells. In order to investigate the importance of modulated lipid metabolism and alterations in mitochondrial properties in this cell death process, we incubated glioma cells both with TTA and the oxidizable fatty acid palmitic acid (PA), in the presence of l-carnitine and the carnitine palmitoyltransferase inhibitors etomoxir and aminocarnitine. l-carnitine partly abolished the PA-mediated growth reduction of glioma cells, whereas etomoxir and aminocarnitine enhanced the antiproliferative effect of PA. The production of acid-soluble products increased and the incorporation of PA into glycerolipids decreased after l-carnitine supplementation. l-carnitine was found to enhance the antiproliferative effect of TTA, but did not affect the incorporation of TTA into glycerolipids, or ceramide. PDMP, sphingosine 1-phosphate, desipramine, fumonisin B1, and l-cycloserine were able not to rescue the glioma cells from PA and TTA-induced growth inhibition, suggesting that increased ceramide production is not important in the growth reduction. TTA-mediated growth inhibition was accompanied with an increased uptake of PA and increased incorporation of PA into triacylglycerol (TG).Our data suggest that mitochondrial functions are involved in fatty acid-mediated growth inhibition. Whether there is a causal relationship between TG accumulation and the apoptotic process remains to be determined.

The role of insulin/insulin-like growth factor (IGF) signaling pathway in the growth regulation of marine invertebrates has not been fully studied. In this study, the economically important species Ruditapes philippinarum was sacrificed to clarify the role of IGF system in the growth regulation of R. philippinarum by real-time quantitative PCR. Systematic bioinformatics analysis can identify the major genes of IGF signaling pathway and insulin-like peptide receptor (ILPR) - mediated signaling pathway in R. philippinarum. The expression levels of IGF and its downstream signaling pathway genes in larger clams were significantly higher than those in small clams, indicating that they were involved in the growth regulation of R. philippinarum. These results suggest that IGF signaling pathway and ILPR mediated signaling pathway to regulate the growth of R. philippinarum. [Display omitted] • This study identified and characterized the insulin-like peptide receptors in R. philippinarum. • The expression profiles of insulin-like peptide receptors were analyzed in R. philippinarum. • The results provide useful information for further research on the growth regulation of shellfish. [ABSTRACT FROM AUTHOR]

Background: The variation of growth and cold tolerance of two natural Arabidopsis accessions, Cvi (cold sensitive) and Rschew (cold tolerant), was analysed on a proteomic, phosphoproteomic and metabolomic level to derive characteristic information about genotypically distinct strategies of metabolic reprogramming and growth maintenance during cold acclimation. Results: Growth regulation before and after a cold acclimation period was monitored by recording fresh weight of leaf rosettes. Significant differences in the shoot fresh weight of Cvi and Rschew were detected both before and after acclimation to low temperature. During cold acclimation, starch levels were found to accumulate to a significantly higher level in Cvi compared to Rschew. Concomitantly, statistical analysis revealed a cold-induced decrease of beta-amylase 3 (BAM3; AT4G17090) in Cvi but not in Rschew. Further, only in Rschew we observed an increase of the protein level of the debranching enzyme isoamylase 3 (ISA3; AT4G09020). Additionally, the cold response of both accessions was observed to severely affect ribosomal complexes, but only Rschew showed a pronounced accumulation of carbon and nitrogen compounds. The abundance of the Cold Regulated (COR) protein COR78 (AT5G52310) as well as its phosphorylation was observed to be positively correlated with the acclimation state of both accessions. In addition, transcription factors being involved in growth and developmental regulation were found to characteristically separate the cold sensitive from the cold tolerant accession. Predicted protein-protein interaction networks (PPIN) of significantly changed proteins during cold acclimation allowed for a differentiation between both accessions. The PPIN revealed the central role of carbon/nitrogen allocation and ribosomal complex formation to establish a new cold-induced metabolic homeostasis as also observed on the level of the metabolome and proteome. Conclusion: Our results provide evidence for a comprehensive multi-functional molecular interaction network orchestrating growth regulation and cold acclimation in two natural accessions of Arabidopsis thaliana. The differential abundance of beta-amylase 3 and isoamylase 3 indicates a central role of transitory starch degradation in the coordination of growth regulation and the development of stress tolerance. Finally, our study indicates naturally occurring differential patterns of C/N balance and protein synthesis during cold acclimation. [ABSTRACT FROM AUTHOR]

'I see no physical reason why it should not have been possible for life to construct ageless individuals', said Carl von Weizsacker in 1979 at the Conference on DNA. An obvious biological reason for senescence may be the action of a built-in aging program. Many gerontologists believe that early thymic involution is an argument in favor of the existence of such a program. On the other hand, this involution may be a result of the program of development rather than aging. According to the concepts of noninfectious immunology, the immune system of vertebrates is also designed for immune surveillance over initial tumor development and for tissue-specific regulation of cell proliferation both in ontogenesis and during physiological and reparative regeneration of organs and tissues. Natural anti-tissue autoantibodies are the main effectors of such regulation. Therefore, the number of inherited genes of the variable part of immunoglobulin ( V-genes) is not less than the number of all proliferative-competent cell types (~100). For the same reason, the maximal rate of growth, which is usually observed in the prepubertal period, coincides with the maximal thymus index and the maximal number of immunoglobulin-secreting cells as well as the minimal force of mortality during ontogeny. Thus, the circa-pubertal beginning of thymic involution is probably caused by the programmed deceleration of the growth rate in ontogeny, and not by the early manifestation of an aging program. This approach allows us to understand the mechanism of the well-known antitumor effect of the regeneration process of the organ homologous to the tumor, and hence we can try to use it in practical oncology. [ABSTRACT FROM AUTHOR]

Plants survive periods of unfavourable conditions with the help of sensory mechanisms that respond to reactive oxygen species (ROS) as signalling molecules in different cellular compartments. We have previously demonstrated that protein phosphatase 2A (PP2A) impacts on organellar cross-talk and associated pathogenesis responses in A rabidopsis thaliana. This was evidenced by drastically enhanced pathogenesis responses and cell death in cat2 pp2a-b′γ double mutants, deficient in the main peroxisomal antioxidant enzyme CATALASE 2 and PP2A regulatory subunit B′ γ (PP2A-B′ γ). In the present paper, we explored the impacts of PP2A-B′ γ and a highly similar regulatory subunit PP2A-B′ ζ in growth regulation and light stress tolerance in Arabidopsis. PP2A - B ′γ and PP2A - B ′ζ display high promoter activities in rapidly growing tissues and are required for optimal growth under favourable conditions. Upon acclimation to a combination of high light, elevated temperature and reduced availability of water, however, pp2a-b′γζ double mutants grow similarly to the wild type and show enhanced tolerance against photo-oxidative stress. We conclude that by controlling ROS homeostasis and signalling, PP2A-B′ γ and PP2A-B′ ζ may direct acclimation strategies upon environmental perturbations, hence acting as important determinants of defence responses and light acclimation in plants. [ABSTRACT FROM AUTHOR]

Abstracts Although Metastatic-tumor antigen 1 (MTA1) is differentially expressed in metastatic cancer and coregulates the status and activity of nuclear receptors, its role upon estrogen receptor β (ERβ) – a potent tumor suppressor, remains poorly understood. Here we investigated whether MTA1 regulates the expression and functions of ERβ, an ER isoform predominantly expressed in salivary gland cancer cells. We found that the depletion of the endogenous MTA1 in the HSG and HSY salivary duct carcinoma cell lines enhances the expression of ERβ while MTA1 overexpression augmented the expression of ERβ in salivary duct carcinoma cells. Furthermore, MTA1 knockdown inhibited the proliferations and invasion of HSG and HSY cells. The noted ERβ downregulation by MTA1 overexpression involves the process of proteasomal degradation, as a proteasome inhibitor could block it. In addition, both MTA1 knockdown and ERβ overexpression attenuated the cell migration and inhibited the ERK1/2 signaling in the both cell lines. These findings imply that MTA1 dysregulation in a subset of salivary gland cancer might promote aggressive phenotypes by compromising the tumor suppressor activity of ERβ, and hence, MTA1-ERβ axis might serve a new therapeutic target for the salivary gland cancer. [ABSTRACT FROM AUTHOR]

Chloroplasts regulate their growth to optimize photosynthesis. Quantitative data show that the ratio of total chloroplast area to mesophyll cell area is constant across different cells within a single species and also across species. Wild-type chloroplasts exhibit little scatter around this trend; highly irregularly shaped mutant chloroplasts exhibit more scatter. Here we propose a model motivated by a bacterial quorum-sensing model consisting of a switch-like signaling network that turns off chloroplast growth. We calculated the dependence of the location of the relevant saddle-node bifurcation on the geometry of the chloroplasts. Our model exhibits a linear trend, with linearly growing scatter dependent on chloroplast shape, consistent with the data. When modeled chloroplasts are of a shape that grows with a constant area-to-volume ratio (disks, cylinders), we find a linear trend with minimal scatter. Chloroplasts with area and volume that do not grow proportionally (spheres) exhibit a linear trend with additional scatter. [ABSTRACT FROM AUTHOR]

To gain a better understanding of the mechanisms by which cortisol suppresses growth during chronic stress in fish, we characterized the effects of chronic cortisol on food intake, mass gain, the expression of appetite-regulating factors, and the activity of the GH/IGF axis. Fish given osmotic pumps that maintained plasma cortisol levels at w70 or 116 ng/ml for 34 days were sampled 14, 28 and 42 days post-implantation. Relative to shams, the cortisol treatments reduced food intake by 40-60% and elicited marked increases in liver leptin (lep-a1) and brain preoptic area (POA) corticotropin-releasing factor (crf) mRNA levels. The cortisol treatments also elicited 40-80% reductions in mass gain associated with increases in pituitary gh, liver gh receptor (ghr), liver igfI and igf binding protein (igfbp)-1 and -2 mRNA levels, reduced plasma GH and no change in plasma IGF1. During recovery, while plasma GH and pituitary gh, liver ghr and igfI gene expression did not differ between treatments, the high cortisol-treated fish had lower plasma IGF1 and elevated liver igfbp1 mRNA levels. Finally, the cortisol-treated fish had higher plasma glucose levels, reduced liver glycogen and lipid reserves, and muscle lipid content. Thus, our findings suggest that the growth-suppressing effects of chronic cortisol in rainbow trout result from reduced food intake mediated at least in part by increases in liver lep-a1 and POA crf mRNA, from sustained increases in hepatic igfbp1 expression that reduce the growth-promoting actions of the GH/IGF axis, and from a mobilization of energy reserves. [ABSTRACT FROM AUTHOR]

Growth-regulating factors (GRFs) are plant-specific transcription factors that were originally identified for their roles in stem and leaf development, but recent studies highlight them to be similarly important for other central developmental processes including flower and seed formation, root development, and the coordination of growth processes under adverse environmental conditions. The expression of several GRFs is controlled by microRNA miR396 , and the GRF - miRNA396 regulatory module appears to be central to several of these processes. In addition, transcription factors upstream of GRFs and miR396 have been discovered, and gradually downstream target genes of GRFs are being unraveled. Here, we review the current knowledge of the biological functions performed by GRFs and survey available molecular data to illustrate how they exert their roles at the cellular level. [ABSTRACT FROM AUTHOR]

The reactive aldehyde 4-hydroxynonenal (HNE) is major bioactive marker of lipid peroxidation generated under oxidative stress from polyunsaturated fatty acids. Biomedical significance of HNE was first revealed in pathogenesis of various degenerative and malignant diseases. Thus, HNE was considered for decades only as cytotoxic molecule, 'second toxic messenger of free radicals' responsible for numerous undesirable consequences of oxidative stress. However, the increase of knowledge on physiology of redox signaling revealed also desirable, physiological roles of HNE, especially in the field of cellular signaling pathways regulating proliferation, differentiation, and apoptosis. These pluripotent effects of HNE can be explained by its concentration-dependent interactions with the cytokine networks and complex cellular antioxidant systems also showing cell and tissue specificities. Therefore, this paper gives a comprehensive, yet short overview on HNE as pluripotent growth-regulating factor. [ABSTRACT FROM AUTHOR]

The evolutionarily conserved Hippo signaling pathway is known to regulate cell proliferation and maintain tissue homeostasis during development. We found that activation of Yorkie (Yki), the effector of the Hippo signaling pathway, causes separable effects on growth and differentiation of the Drosophila eye. We present evidence supporting a role for Yki in suppressing eye fate by downregulation of the core retinal determination genes. Other upstream regulators of the Hippo pathway mediate this effect of Yki on retinal differentiation. Here, we show that, in the developing eye, Yki can prevent retinal differentiation by blocking morphogenetic furrow (MF) progression and R8 specification. The inhibition of MF progression is due to ectopic induction of Wingless (Wg) signaling and Homothorax (Hth), the negative regulators of eye development. Modulating Wgsignaling can modify Yki-mediated suppression of eye fate. Furthermore, ectopic Hth induction due to Yki activation in the eye is dependent on Wg. Last, using Cut (Ct), a marker for the antennal fate, we show that suppression of eye fate by hyperactivation of yki does not change the cell fate (from eye to antenna-specific fate). In summary, we provide the genetic mechanism by which yki plays a role in cell fate specification and differentiation - a novel aspect of Yki function that is emerging from multiple model organisms. [ABSTRACT FROM AUTHOR]

In social groups, hierarchies are the fundamental organizational unit and integral to the structure of social groups. For many social fishes, rank is determined by body size and conflict over rank is resolved via aggressive threats from dominants and growth restraint by subordinates. However, this balance may be offset by an alteration of abiotic factors, such as elevated temperature expected from climate change, which could thereby disrupt the usual mechanisms of conflict resolution. Here, we determined the effect of elevated temperature on hierarchy structure, stability, and conflict resolution in the Eastern mosquitofish, Gambusia holbrooki. Body size was significantly related to dominance rank, and aggression was more commonly directed toward subordinates and was heightened between individuals of adjacent rank, demonstrating that conflict over rank occurs in size-based hierarchies. Temperature did not affect overall levels or directionality/adjacency of aggression but substantially altered subordinate growth patterns. In only the high-temperature groups, growth rates of subordinates decreased as the size ratio between themselves and their immediate dominant approached 1.0, whereas growth rates of dominants were unaffected. This unique finding suggests that only under high temperatures, subordinates may adopt growth regulation to resolve conflict, when the costs of conflict with dominants are greater. This provides the first causal link between abiotic stressors and changes to hierarchical structure and functioning, providing a springboard for further research into implications of temperature-dependent subordinate growth alteration at higher levels of ecological organization. [ABSTRACT FROM AUTHOR]

Having a strong effect on plant growth, temperature adaption has become a major breeding aim. Due to a lack of efficient methods, we developed an image-based approach to characterise genotypes for their temperature behaviour in the field. Twenty-nine winter wheat (Triticum aestivum L.) genotypes were continuously monitored at 3-day intervals on a plot basis during early growth from November to March using a modified digital camera. Canopy cover (CC) was determined by segmentation of leaves in calibrated images. Relative growth rates (RGR) of CC were then calculated for each measurement interval and related to the respective temperature. Also, classical traits used in plant breeding were assessed. Measurements of CC at single dates were highly repeatable with respect to genotype. For the tested range of temperatures (0 -- 7°C), a linear relation between RGR and temperature was observed. Genotypes differed for base temperature and increase in RGR with rising temperature, these two traits showing a strong positive correlation with each other but being independent of CC at a single date. Our simple approach is suitable to screen large populations for differences in growth response to environmental stimuli. Furthermore, the derived parameters reveal additional information that cannot be assessed by usual measurements of static size. [ABSTRACT FROM AUTHOR]

In this study, immunization against chicken leptin receptor (cLEPR) extracellular domain (ECD) was applied to investigate leptin regulation and LEPR biofunction in growing chicken pullets. A recombinant protein (cLEPR ECD) based on the cLEPR complemenary DNA sequence corresponding to the 582nd to 796th amino acid residues of cLEPR mature peptide was prepared and used as antigen. Immunization against cLEPR ECD in growing chickens increased anti-cLEPR ECD antibody titers in blood, enhanced proportions of phosphorylated janus kinase 2 (JAK2) and served as signal transducer and activator of transcription 3 (STAT3) protein in liver tissue. Chicken live weight gain and abdominal fat mass were significantly decreased ( P < 0.05), but feed intake was stimulated by cLEPR ECD immunization ( P < 0.05). The treatment also upregulated the gene expression levels of lepR , AMP-activated protein kinase ( AMPK ), acetyl CoA carboxylase-2 ( ACC2 ), and uncoupling protein 3 ( UCP3 ) in liver, abdominal fat, and breast muscle ( P < 0.05) but decreased fasn expression levels ( P < 0.01). Apart from that of lepR , the expression of appetite-regulating genes, such as orexigenic genes, agouti-related peptide ( AgRP ) and neuropeptide Y ( NPY ), were upregulated ( P < 0.01), whereas the anorexigenic gene proopiomelanocortin ( POMC ) was downregulated in the hypothalamic tissue of cLEPR-immunized pullets ( P < 0.01). Blood concentrations of metabolic molecules, such as glucose, triglycerides, and very-low-density lipoprotein, were significantly decreased in cLEPR-immunized pullets but those of cholesterol, high-density lipoprotein, and low-density lipoprotein increased. These results demonstrate that antibodies to membrane proximal cLEPR ECD enhance cLEPR signal transduction, which stimulates metabolism and reduces fat deposition in chickens. [ABSTRACT FROM AUTHOR]

We investigated the effects of manipulating the atmospheric oxygen (O 2 ) concentration around white asparagus rootstocks planted in pots to evaluate the applicability of this technique for growth regulation in white asparagus production. The O 2 concentrations around the pots were adjusted to 5%, 10%, 20%, 40%, 60%, and 80%, and plants were exposed to these conditions over a 38-d period. We found that the time of both initial sprouting (i.e., when the length of the first emerging spears reached >30 mm) and harvesting were delayed when the O 2 concentration around the pots was 5%; moreover, decreases in the soluble solids contents (SSCs) of the storage roots were inhibited at 5% O 2 relative to the control (20% O 2 ). These delays were likely due to a hypoxic effect, which inhibits the metabolism of some respiratory substrates such as sugars and/or organic acids. Under the 5% O 2 treatment, the O 2 concentration during the gaseous phase of the soil in the pot was estimated to be 12.4–14.4%; therefore, sprouting should be delayed when the O 2 concentration around the roots is <15%. Our results also showed that the rate of spear elongation decreased when the O 2 concentration around the spears was within the range of 60–80%. Considering that the 40% O 2 concentration did not affect the rate of spear elongation, it appears that the threshold for this phenomenon is an O 2 concentration of 40–60%. When the rootstocks grown under each O 2 treatment were replanted and cultured under normal atmospheric conditions for 25 d, no significant differences were found in growth and yield ability, such as the time of initial harvesting, number of harvested spears, yield, and spear weight. Therefore, the effects of different atmospheric O 2 concentrations did not continue after cessation of the experimental treatments. Our results suggest that controlling the O 2 concentration around rootstocks may be a new method for the growth regulation of white asparagus. We also expect that the new method can be applied in a closed cultivation system as well as in a plant factory. [ABSTRACT FROM AUTHOR]

Understanding the genetic basis of variation in traits related to growth and fillet quality in Atlantic salmon is of importance to the aquaculture industry. Several growth-related QTL have been identified via the application of genetic markers. The IGF1 gene is considered a highly conserved and crucial growth-regulating gene in salmonid species. However, the association between polymorphisms in the IGF1 gene and growth-related traits in Atlantic salmon is unknown. Therefore, in this study, regions of the Atlantic salmon IGF1 gene were sequenced, aligned and compared across individuals. Three SNPs were identified in the putative promoter ( SNP1, g.5763G>T; GenBank no. ), intron 1 ( SNP2, g.7292C>T; GenBank no. ) and intron 3 ( SNP3, g.4671A>C; GenBank no. ) regions respectively. These SNPs were genotyped in a population of 4800 commercial Atlantic salmon with data on several weight and fillet traits measured at harvest (at approximately 3 years of age). In a mixed model, association analysis of individual SNPs, SNP1 and SNP3 were both significantly associated with several weight traits ( P < 0.05). The estimated additive effect on overall harvest weight was approximately 35 and 110 g for SNPs 1 and 3 respectively. A haplotype analysis confirmed the association between genetic variation in the IGF1 gene with overall body weight ( P < 0.05) and fillet component traits ( P < 0.05). Our findings suggest the identified nucleotide polymorphisms of the IGF1 gene may either affect farmed Atlantic salmon growth directly or be in population-wide linkage disequilibrium with causal variation, highlighting their possible utility as candidates for marker-assisted selection in the aquaculture industry. [ABSTRACT FROM AUTHOR]