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https://www.readbyqxmd.com/read/28325169/a-new-substitute-host-and-its-effects-on-some-biological-properties-of-ooencyrtus-kuvanae
#1
Hilal Tunca, Marine Venard, Etty-Ambre Colombel, Elisabeth Tabone
Lymantia dispar (L.) (Lepidoptera: Lymantriidae), commonly known as the gypsy moth, is a serious forest pest, and beneficial insects are particularly important for reducing its population numbers. Ooencyrtus kuvanae (Howard) (Hymenoptera: Encyrtidae) is an arrhenotokous, solitary egg parasitoid of L. dispar. In this study, we evaluated a new substitute host, Philosamia ricini (Danovan) (Lepidoptera: Saturniidae) for O. kuvanae. We investigated some of the biological effects of O. kuvanae on P. ricini eggs. In this context, the importance of the age of the female parasitoid (1, 3 or 5 days old), host age (1-2 and 3-4 days old) and host number (40, 60 and 80 host eggs) were examined under laboratory conditions (25 ± 1 °C, 65 ± 5% relative humidity and a 16 : 8 h photoperiod [light : dark])...
March 22, 2017: Bulletin of Entomological Research
https://www.readbyqxmd.com/read/28324762/chrysanthemum-morphology-photosynthetic-efficiency-and-antioxidant-capacity-are-differentially-modified-by-light-quality
#2
Liang Zheng, Marie-Christine Van Labeke
The effect of light quality on leaf morphology, photosynthetic efficiency and antioxidant capacity of leaves that fully developed under a specific spectrum was investigated in Chrysanthemum cv. Four light treatments were applied at 100μmolm(-2)s(-1) and a photoperiod of 14h using light-emitting diodes, which were 100% red (R), 100% blue (B), 75% red with 25% blue (RB) and white (W), respectively. Intraspecific variation was investigated by studying the response of eight cultivars. Overall, red light significantly decreased the leaf area while the thinnest leaves were observed for W...
March 11, 2017: Journal of Plant Physiology
https://www.readbyqxmd.com/read/28324740/evolution-fruit-fly-clocks-on-the-edge
#3
Charalambos P Kyriacou
Fruit flies evolved in tropical regions under stable light-dark cycles. However, their photosensitive circadian clock had to adapt to extreme seasonal photoperiods during their colonisation of temperate regions. This was achieved by changing the neuronal expression of two key clock-related components.
March 20, 2017: Current Biology: CB
https://www.readbyqxmd.com/read/28324157/water-fat-mri-in-a-hibernator-reveals-seasonal-growth-of-white-and-brown-adipose-tissue-without-cold-exposure
#4
Amanda MacCannell, Kevin Sinclair, Lannette Friesen-Waldner, Charles A McKenzie, James F Staples
Obligate hibernators, such as ground squirrels, display circannual patterns which persist even under constant laboratory conditions, suggesting that they are regulated by endogenous rhythms. Brown adipose tissue (BAT) is important for thermogenesis during periodic arousals from hibernation when core body temperature rises spontaneously from 5 to 37 °C. In most small eutherians BAT growth requires several weeks of cold exposure. We hypothesized that in the thirteen-lined ground squirrel (Ictidomys tridecemlineatus), a hibernator, BAT growth is regulated, in part, by an endogenous rhythm and we predicted that this growth would precede the hibernation season without cold exposure...
March 21, 2017: Journal of Comparative Physiology. B, Biochemical, Systemic, and Environmental Physiology
https://www.readbyqxmd.com/read/28322186/effect-of-isoflurane-anesthesia-on-circadian-metabolism-and-physiology-in-rats
#5
Melissa A Wren-Dail Robert T Dauchy David E Blask Steven M Hill Tara G Ooms Lynell M Dupepe And Rudolf P Bohm
Isoflurane anesthesia alters the blood levels of several neuroendocrine hormones associated with normal metabolism andphysiology and increases stress, but the effect of brief CO2 anesthesia on these parameters is unknown. In this study, we examined the effects of isoflurane (4%) compared with brief CO2 (70% CO2, 30% air) anesthesia on circadian rhythms of plasma measures of physiology and metabolism. Adult male Sprague-Dawley rats (Crl:SD; n = 6 per group) were maintained on a 12:12-h light:dark(300 lx; lights on, 0600) photoperiod...
March 20, 2017: Comparative Medicine
https://www.readbyqxmd.com/read/28321526/effects-of-fasting-temperature-and-photoperiod-on-preproghrelin-mrna-expression-in-chinese-perch
#6
Yi Song, Cheng Zhao, Xu-Fang Liang, Shan He, Changxu Tian, Xiaoyan Cheng, Xiaochen Yuan, Liyuan Lv, Wenjie Guo, Min Xue, Ya-Xiong Tao
Preproghrelin, a gut/brain peptide, plays an important role in the regulation of food intake and energy homeostasis in teleost and mammals. In the present study, we obtained the full-length preproghrelin cDNA in Chinese perch. The preproghrelin messenger RNA (mRNA) tissue expression showed that level was much higher in stomach and pituitary than in other tissues. The fasting study showed, after gastric emptying (3-6 h), short-term fasting (6-12 h) increased preproghrelin expression in the stomach. While in the pituitary, fasting reduced preproghrelin expression at 1, 3, 12, and 48 h, presenting state fluctuation of self-adjustment...
March 20, 2017: Fish Physiology and Biochemistry
https://www.readbyqxmd.com/read/28319089/natural-variation-at-the-soybean-j-locus-improves-adaptation-to-the-tropics-and-enhances-yield
#7
Sijia Lu, Xiaohui Zhao, Yilong Hu, Shulin Liu, Haiyang Nan, Xiaoming Li, Chao Fang, Dong Cao, Xinyi Shi, Lingping Kong, Tong Su, Fengge Zhang, Shichen Li, Zheng Wang, Xiaohui Yuan, Elroy R Cober, James L Weller, Baohui Liu, Xingliang Hou, Zhixi Tian, Fanjiang Kong
Soybean is a major legume crop originating in temperate regions, and photoperiod responsiveness is a key factor in its latitudinal adaptation. Varieties from temperate regions introduced to lower latitudes mature early and have extremely low grain yields. Introduction of the long-juvenile (LJ) trait extends the vegetative phase and improves yield under short-day conditions, thereby enabling expansion of cultivation in tropical regions. Here we report the cloning and characterization of J, the major classical locus conferring the LJ trait, and identify J as the ortholog of Arabidopsis thaliana EARLY FLOWERING 3 (ELF3)...
March 20, 2017: Nature Genetics
https://www.readbyqxmd.com/read/28314822/topography-and-lateralized-effect-of-acute-aromatase-inhibition-on-auditory-processing-in-a-seasonal-songbird
#8
Geert De Groof, Jacques Balthazart, Charlotte A Cornil, Annemie Van der Lindena
It is increasingly recognized that brain-derived estrogens (neuroestrogens) can regulate brain physiology and behavior much faster than what was previously known from the transcriptional action of estrogens on nuclear receptors. One of the best examples of such neuromodulation by neuroestrogens concerns the acute regulation of sensory coding by the auditory cortex as demonstrated by electrophysiological studies of selected neurons in zebra finches. Yet, the spatial extent of such modulation by neuroestrogens is not known...
March 17, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/28303945/dependence-of-nighttime-sleep-duration-in-one-month-old-infants-on-alterations-in-natural-and-artificial-photoperiod
#9
Sachiko Iwata, Fumie Fujita, Masahiro Kinoshita, Mitsuaki Unno, Takashi Horinouchi, Seiichi Morokuma, Osuke Iwata
Human sleep-wake cycles are entrained by both natural and artificial light-dark cycles. However, little is known regarding when and how the photoperiod changes entrain the biological clock after conception. To investigate the dependence of sleep patterns in young infants on the natural and artificial light-dark cycles, 1,302 pairs of one-month-old infants and their mothers were asked to answer a questionnaire. Birth in spring, longer daytime sleep duration, early/regular light-off times, and longer maternal nighttime sleep duration were identified as independent variables for longer infant nighttime sleep duration in both univariate and multivariate analyses...
March 17, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28303652/photoperiod-cues-and-patterns-of-genetic-variation-limit-phenological-responses-to-climate-change-in-warm-parts-of-species-range-modeling-diameter-growth-cessation-in-coast-douglas-fir
#10
Kevin R Ford, Constance A Harrington, J Bradley St Clair
The phenology of diameter-growth cessation in trees will likely play a key role in mediating species and ecosystem responses to climate change. A common expectation is that warming will delay cessation, but the environmental and genetic influences on this process are poorly understood. We modeled the effects of temperature, photoperiod and seed-source climate on diameter-growth cessation timing in coast Douglas-fir (an ecologically and economically vital tree) using high-frequency growth measurements across broad environmental gradients for a range of genotypes from different seed sources...
March 16, 2017: Global Change Biology
https://www.readbyqxmd.com/read/28303175/responses-of-holocyclic-and-anholocyclic-rhopalosiphum-padi-populations-to-low-temperature-and-short-photoperiod-induction
#11
Xiong Peng, Xianfeng Qiao, Maohua Chen
The different life cycles of aphid species make these organisms good models for studying the short-term consequences of sex. The bird cherry-oat aphid Rhopalosiphum padi has a wide geographic distribution and correspondingly different life cycles. In this study, the life cycles of R. padi collected from six different regions in China were characterized experimentally by comparing the responses of holocyclic and anholocyclic populations to low-temperature and short-photoperiod induction. Clones collected from Chuzhou, Taian, and Taigu consistently reproduced via obligate parthenogenesis, whereas clones from Hami and Baicheng were holocyclic in their response, and those from Lanzhou were both holocyclic and anholocyclic...
February 2017: Ecology and Evolution
https://www.readbyqxmd.com/read/28299428/the-avian-hippocampus-and-the-hypothetical-maps-used-by-navigating-migratory-birds-with-some-reflection-on-compasses-and-migratory-restlessness
#12
Verner P Bingman, Scott A MacDougall-Shackleton
The homology between the avian hippocampal formation (HF) and mammalian hippocampus nurtures the expectation that HF plays a fundamental role in navigation by migratory birds. Indeed, HF of migratory birds displays anatomical properties that differ from non-migratory species. Using a hypothetical framework of multiple maps of differing spatial resolution and range, homing pigeon data suggest that HF is important for navigating by landscape features near familiar breeding, over-wintering, and stop-over sites...
March 16, 2017: Journal of Comparative Physiology. A, Neuroethology, Sensory, Neural, and Behavioral Physiology
https://www.readbyqxmd.com/read/28295807/interaction-of-melatonin-and-gonadotropin-inhibitory-hormone-on-the-zebrafish-brain-pituitary-reproductive-axis
#13
Thangal Yumnamcha, Zeeshan Ahmad Khan, Chongtham Rajiv, Sijagurumayum Dharmajyoti Devi, Gopinath Mondal, Haobijam Sanjita Devi, Rupjyoti Bharali, Asamanja Chattoraj
Circadian cycles and photoperiod are known to influence reproductive physiology in several animals. Neuropeptides, such as gonadotropin-inhibitory hormone (GNIH) and gonadotropin-releasing hormone (GNRH), are influenced by melatonin in birds and mammals. The present study demonstrates the role of melatonin in oocyte maturation in the zebrafish (Danio rerio), via the brain-pituitary-reproductive axis, under different photic conditions. Melatonin was significantly higher both in the whole brain and ovary under continuous dark (DD) compared to continuous light (LL) conditions...
March 10, 2017: Molecular Reproduction and Development
https://www.readbyqxmd.com/read/28295708/seasonal-alterations-in-the-daily-rhythms-in-hypothalamic-expression-of-genes-involved-in-the-photoperiodic-transduction-and-neurosteroid-dependent-processes-in-migratory-blackheaded-buntings
#14
Ila Mishra, Devraj Singh, Vinod Kumar
This study investigated seasonal alterations in the daily rhythms of hypothalamic expression of genes involved in the photoperiodic regulation of annual cycles in birds. We measured 4-hourly mRNA expression of genes involved in the photoperiodic transduction (OPN5, EYA3, CGA, TSHβ, DIO2, DIO3) and neurosteroid-dependent processes (AR, CYP19, ERα, ERβ) in the hypothalamus of migratory blackheaded buntings photoinduced with photosensitive, photostimulated (early and late stimulated) and photorefractory seasonal states...
March 14, 2017: Journal of Neuroendocrinology
https://www.readbyqxmd.com/read/28293860/tissue-specific-daily-variation-in-the-oxidative-status-of-sturgeon-acipenser-naccarii-and-rainbow-trout-oncorhynchus-mykiss-a-comparative-study
#15
M C Hidalgo, C E Trenzado, M Furné, A Beltrán, C Manzaneda, M García-Gallego, A Domezain, A Sanz
The oxidative status is associated with animal lifespan, metabolism, activity and circadian rhythms. The objective of this work is to study the time course of the oxidative status over a daily cycle in the plasma, liver and brain, and the changes in the plasma cortisol levels of sturgeon and trout. The knowledge of daily oxidative status will provide a better understanding of the trout and sturgeon physiology and adequate maintenance and food supply of farmed fish in relation to photoperiod. Superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione transferase, DT-diaphorase activities, lipid peroxidation and cortisol were measured...
March 14, 2017: Fish Physiology and Biochemistry
https://www.readbyqxmd.com/read/28290260/feeding-performance-and-life-table-parameters-of-khapra-beetle-trogoderma-granarium-everts-coleoptera-dermestidae-on-various-barley-cultivars
#16
A Golizadeh, Z Abedi
The Khapra beetle, Trogoderma granarium Everts (Coleoptera: Dermestidae), is a common pest of cereal grains and other stored products. In this study, the effects of ten barley cultivars (Abidar, Bahman, Line20, Line22, Line30, Lisuei, Lokht11, Makuyi, Sahand, and Sahraa) were evaluated on life table parameters and nutritional indices of T. granarium under the following laboratory conditions: 33 ± 1°C, 60 ± 5% RH, and a photoperiod of 14: 10 (L: D) h. Life history parameters of T. granarium could be appropriate indices in resistance and susceptibility evaluation of barley cultivars...
March 14, 2017: Bulletin of Entomological Research
https://www.readbyqxmd.com/read/28284990/modeling-the-photoperiodic-entrainment-of-the-plant-circadian-clock
#17
Joëlle De Caluwé, José Romário Fernandes de Melo, Alen Tosenberger, Christian Hermans, Nathalie Verbruggen, Jean-Christophe Leloup, Didier Gonze
The circadian clock is an endogenous 24hour rhythm that helps organisms anticipate and adapt to daily and seasonal variations in environment, such as the day/night cycle or changing temperatures. The plant clock is a complex network of transcription factors that regulate each other, forming interlocked feedback loops. Most of its components are light-regulated in some way, making the system highly sensitive to changes in light conditions. Here, we explore the mechanisms by which the plant clock adapts to changing day length...
March 8, 2017: Journal of Theoretical Biology
https://www.readbyqxmd.com/read/28279674/effect-of-photoperiod-and-6-methoxybenzoxazolinone-6-mboa-on-the-reproduction-of-male-brandt-s-voles-lasiopodomys-brandtii
#18
Xin Dai, Jia Shi, Mei Han, Ai Qin Wang, Wan Hong Wei, Sheng Mei Yang
Plant secondary metabolite 6-methoxybenzoxazolinone (6-MBOA) has been suggested to stimulate animal reproduction. 6-MBOA is detected in Leymus chinensis, a main diet of Brandt's vole (Lasiopodomys brandtii). We have previously reported a stimulatory effect of 6-MBOA on reproduction of male Brandt's voles under a short-day photoperiod. The goal of this study was to investigate the effect of 6-MBOA on reproductive physiology of male Brandt's voles under a long-day photoperiod and examine if 6-MBOA under this photoperiodic regime altered the reproductive status of male Brandt's voles differently than the short-day photoperiod...
March 6, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28270617/mechanisms-regulating-angiogenesis-underlie-seasonal-control-of-pituitary-function
#19
Jennifer Castle-Miller, David O Bates, Domingo J Tortonese
Seasonal changes in mammalian physiology, such as those affecting reproduction, hibernation, and metabolism, are controlled by pituitary hormones released in response to annual environmental changes. In temperate zones, the primary environmental cue driving seasonal reproductive cycles is the change in day length (i.e., photoperiod), encoded by the pattern of melatonin secretion from the pineal gland. However, although reproduction relies on hypothalamic gonadotrophin-releasing hormone output, and most cells producing reproductive hormones are in the pars distalis (PD) of the pituitary, melatonin receptors are localized in the pars tuberalis (PT), a physically and functionally separate part of the gland...
March 7, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28270524/pseudo-response-regulators-stabilize-constans-protein-to-promote-flowering-in-response-to-day-length
#20
Ryosuke Hayama, Liron Sarid-Krebs, René Richter, Virginia Fernández, Seonghoe Jang, George Coupland
Seasonal reproduction in many organisms requires detection of day length. This is achieved by integrating information on the light environment with an internal photoperiodic time-keeping mechanism. Arabidopsis thaliana promotes flowering in response to long days (LDs), and CONSTANS (CO) transcription factor represents a photoperiodic timer whose stability is higher when plants are exposed to light under LDs. Here, we show that PSEUDO RESPONSE REGULATOR (PRR) proteins directly mediate this stabilization. PRRs interact with and stabilize CO at specific times during the day, thereby mediating its accumulation under LDs...
March 7, 2017: EMBO Journal
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