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Early Growth (early + growth)
Terms modified by Early Growth Selected AbstractsInfluence of Soil Temperature on Seedling Emergence and Early Growth of Peanut Cultivars in Field ConditionsJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 3 2006P. V. V. Prasad Abstract Peanut or groundnut (Arachis hypogaea L.) sown in early spring often has poor seed germination and seedling development. The influence of soil temperature on seedling emergence and early growth of six peanut cultivars (Florida MDR98, Southern Runner, Georgia Green, SunOleic 97R, Florunner and C-99R) was studied in natural field soil profiles in temperature-gradient greenhouses. We evaluated the influence of a range of soil temperatures by sowing at eight dates between January 2001 and May 2002 in Gainesville, Florida. On each sowing date, two additional temperature treatments (ambient and ambient +4.5 °C air temperature) were evaluated by sowing on either end of each greenhouse and applying differential heating. In total, 16 different soil temperature treatments were evaluated. Each treatment was replicated four times in four different greenhouses. Mean soil temperature from sowing to final emergence in different treatments ranged from 15 to 32 °C. Sowing date, temperature treatment and cultivar had significant effect on seedling emergence and development (V2 stage). For all cultivars, the lowest germination was observed at the earliest sowing date (coolest soil temperature). Among cultivars, Florida MDR98 was the most sensitive to reduced (cool) temperature with the lowest germination and smallest seedling size at 21 days after sowing, followed by Southern Runner. Georgia Green was the most cold-tolerant with the highest germination, followed by SunOleic 97R. There were no significant differences among cultivars for base temperature, which averaged 11.7 and 9.8 °C for rate of emergence and rate of development to V2 stage respectively. These results imply that cultivar choice and/or genetic improvement of peanut for cold tolerance during emergence and seedling development in regions where cooler soil temperatures persist and/or regions where early sowing is desirable. [source] First summer growth predetermined in anadromous and resident brook charrJOURNAL OF FISH BIOLOGY, Issue 2 2007E. Chernoff Early growth of wild, anadromous and non-anadromous (resident) brook charr Salvelinus fontinalis was compared under controlled laboratory conditions. Offspring were collected as they emerged from natural redds in the Miramichi River, New Brunswick, Canada. Anadromous offspring were initially longer and heavier than residents. Anadromous offspring had lower specific growth rates during their first 2 months post-emergence, but surpassed residents by the third month. Consequently, anadromous offspring remained larger at the end of 3 months and it is concluded that they had a predetermined, maternal and genetic advantage related to body size, rather than an environmentally determined advantage during their first summer of growth. Other studies hypothesize that juvenile development affects life-history strategy adopted as adults, which suggests anadromy in this population may be, at least in part, predetermined by maternal and genetic effects. [source] Growth in colony living anubis baboon infants and its relationship with maternal activity budgets and reproductive statusAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2009Cécile Garcia Abstract Early growth is of interest because it is susceptible to maternal effects and linked to fitness components for a range of species. Here we present anthropometric measurements on 23 infant olive baboons born into a captive colony in order to describe growth over the first 2 years of life, to explore maternal influences on growth, and to assess the impact of growth profiles on maternal reproduction. Six main findings emerged: 1) Infant growth rates in our colony were higher than those reported for wild populations but comparable to those observed for food-enhanced animals. 2) The ratio of infant mass to maternal mass was positively associated with reproductive parameters, such as duration of post-partum amenorrhea and interbirth interval. 3) Mothers resumed cycling and reconceived when their infants attained a relatively consistent threshold mass. 4) Infant mass-for-age was associated with maternal rank and, independently, with maternal mass such that females of high dominance rank and heavy females had relatively large infants at their resumption of cycling. 5) Low-ranking and lighter females had longer investment periods but smaller infants. They continued investment in infant through prolonged lactation until their infants reached a mass similar to that of infants of high-ranking/heavy mothers, suggesting that the lengthening of investment is essentially compensatory for slow early growth. 6) There was no relationship between infant growth and maternal activity budgets. Maternal physical and social factors, not energetics, contributed to differences among infants in growth trajectories, and infant growth temporally influenced successive reproductive events. Am J Phys Anthropol 2009. © 2008 Wiley-Liss, Inc. [source] Ambient ultraviolet-B radiation reduces hatchling size in the common frog Rana temporariaECOGRAPHY, Issue 5 2000Maarit Pahkala Effects of ambient UV-B radiation and pH on hatchability and early development of Rana temporaria embryos were studied in field experiments conducted at two sites in Sweden. In neither of the populations did we find clear evidence for reduced hatchability or increased frequency of developmental anomalies of embryos exposed to ambient UV-B levels. However, in both populations hatchling size was significantly larger UV-B blocked as compared to control treatments, suggesting that ambient UV-B levels had a negative effect on early growth of embryos. This result is consistent with the hypothesis that the cellular UV-B damage repair mechanisms are costly and trades-off against early growth. Alternatively, UV-B induced photoproducts inhibiting DNA-transcription and thereby protein synthesis may directly reduce growth rate. Although low pH (5.0) had negative effects on hatchability and early embryonic growth, there was no evidence for synergistic effects of pH and UV-B on hatchability, frequency of developmental anomalies or early growth. The results suggest that increased levels of UV-B radiation may cause fitness loss in natural populations of the common frog. [source] Comparative development of fiber in wild and cultivated cottonEVOLUTION AND DEVELOPMENT, Issue 1 2001Wendy L. Applequist SUMMARY One of the most striking examples of plant hairs is the single-celled epidermal seed trichome of cultivated cotton. The developmental morphology of these commercial "fibers" has been well-characterized in Gossypium hirsutum, but little is known about the pattern and tempo of fiber development in wild Gossypium species, all of which have short, agronomically inferior fiber. To identify developmental differences that account for variation in fiber length, and to place these differences in a phylogenetic context, we conducted SEM studies of ovules at and near the time of flowering, and generated growth curves for cultivated and wild diploid and tetraploid species. Trichome initiation was found to be similar in all taxa, with few notable differences in trichome density or early growth. Developmental profiles of the fibers of most wild species are similar, with fiber elongation terminating at about two weeks post-anthesis. In contrast, growth is extended to three weeks in the A- and F-genome diploids. This prolonged elongation period is diagnosed as a key evolutionary event in the origin of long fiber. A second evolutionary innovation is that absolute growth rate is higher in species with long fibers. Domestication of species is associated with a further prolongation of elongation at both the diploid and allopolyploid levels, suggesting the effects of parallel artificial selection. Comparative analysis of fiber growth curves lends developmental support to previous quantitative genetic suggestions that genes for fiber "improvement" in tetraploid cotton were contributed by the agronomically inferior D-genome diploid parent. [source] Cardiac and coronary function in the Langendorff-perfused mouse heart modelEXPERIMENTAL PHYSIOLOGY, Issue 1 2009Melissa E. Reichelt The Langendorff mouse heart model is widely employed in studies of myocardial function and responses to injury (e.g. ischaemia). Nonetheless, marked variability exists in its preparation and functional properties. We examined the impact of early growth (8, 16, 20 and 24 weeks), sex, perfusion fluid [Ca2+] and pacing rate on contractile function and responses to 20 min ischaemia followed by 45 min reperfusion. We also assessed the impact of strain, and tested the utility of the model in studying coronary function. Under normoxic conditions, hearts from 8-week-old male C57BL/6 mice (2 mm free perfusate [Ca2+], 420 beats min,1) exhibited 145 ± 2 mmHg left ventricular developed pressure (LVDP). Force development declined by ,15% (126 ± 5 mmHg) with a reduction in free [Ca2+] to 1.35 mm, and by 25% (108 ± 3 mmHg) with increased pacing to 600 beats min,1. While elevated heart rate failed to modify ischaemic outcome, the lower [Ca2+] significantly improved contractile recovery (by >30%). We detected minimal sex-dependent differences in normoxic function between 8 and 24 weeks, although age modified contractile function in males (increased LVDP at 24 versus 8 weeks) but not females. Both male and female hearts exhibited age-related reductions in ischaemic tolerance, with a significant decline in recovery evident at 16 weeks in males and later, at 20,24 weeks, in females (versus recoveries in hearts at 8 weeks). Strain also modified tolerance to ischaemia, with similar responses in hearts from C57BL/6, 129/sv, Quackenbush Swiss and FVBN mice, but substantially greater tolerance in BALB/c hearts. In terms of vascular function, baseline coronary flow (20,25 ml min,1 g,1) was 50,60% of maximally dilated flows, and coronary reactive and functional hyperaemic responses were pronounced (up to 4-fold elevations in flow in hearts lacking ventricular balloons). These data indicate that attention to age (and sex) of mice will reduce variability in contractile function and ischaemic responses. Even small differences in perfusion fluid [Ca2+] also significantly modify tolerance to ischaemia (whereas modest shifts in heart rate do not impact). Ischaemic responses are additionally strain dependent, with BALB/c hearts displaying greatest intrinsic tolerance. Finally, the model is applicable to the study of vascular reactivity, providing large responses and excellent reproducibility. [source] Initiation and early growth of fatigue cracks in an aerospace aluminium alloyFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 2 2002S. A. Barter Abstract Material imperfections usually play a substantial role in the early stages of fatigue cracking. This article presents some observations concerning fatigue crack initiating flaws and early crack growth in 7050-T7451 aluminium alloy specimens and in full-scale fatigue test articles with a production surface finish. Equivalent initial flaw size (EIFS) approaches used to evaluate the fatigue implications of metallurgical, manufacturing and service-induced features were refined by using quantitative fractography to acquire detailed information on the early crack growth behaviour of individual cracks; the crack growth observations were employed in a simple crack growth model developed for use in analysing service crack growth. The use of observed crack growth behaviour reduces the variability which is inherent in EIFS approaches which rely on modelling the whole of fatigue life, and which can dominate EIFS methods. The observations of realistic initial flaws also highlighted some of the significant factors in the fatigue life-determining early fatigue growth phase, such as surface treatment processes. Although inclusions are often regarded as the single most common type of initiating flaw, processes which include etching can lead to etch pitting of grain boundaries with significant fatigue life implications. [source] Corrosion fatigue behaviour of a 15Cr-6Ni precipitation-hardening stainless steel in different tempersFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 6 2000C.-K. Lin Systematic fatigue experiments, including both high-cycle axial fatigue (S,N curves) and fatigue crack growth (FCG, da/dN,,K curves), were performed on a precipitation-hardening martensitic stainless steel in laboratory air and 3.5 wt% NaCl solution. Specimens were prepared in three tempers, i.e. solution-annealed (SA), peak-aged (H900) and overaged (H1150) conditions, to characterize the effects of ageing treatment on the corrosion fatigue (CF) resistance. S,N results indicated that fatigue resistance in all three tempers was dramatically reduced by the aqueous sodium chloride environment. In addition, the smooth-surface specimens in H900 temper exhibited longer CF lives than the H1150 ones, while those in SA condition stood in between. However, for precracked specimens, the H1150 temper provided superior corrosive FCG resistance than the other two tempers. Comparison of the S,N and FCG curves indicated that early growth of crack-like defects and short cracks played the major role in determining the CF life for smooth surface. The differences in the CF strengths for the S,N specimens of the given three tempers were primarily due to their inherent differences in resistance to small crack growth, as they were in the air environment. [source] Interannual variability in hatching period and early growth of juvenile walleye pollock, Theragra chalcogramma, in the Pacific coastal area of HokkaidoFISHERIES OCEANOGRAPHY, Issue 3 2007AKIRA NISHIMURA ABSTRACT Juvenile walleye pollock of the Japanese Pacific population were collected from the Funka Bay [spawning ground; 16,64 mm fork length (FL)] in spring and the Doto area (nursery ground; 70,146 mm FL) in summer. Hatch dates were estimated by subtracting the number of otolith daily increments from sampling dates, and their early growth was back-calculated using otolith radius,somatic length relationships. Interannual change of the hatching period was observed during 2000,02, and the peaks ranged from mid-February in 2000 to early-April in 2002. In 2000, when a strong year class occurred, early life history of the surviving juveniles could be characterized by early hatching and slower growth in the larval stage (<22 mm length). Higher growth rate in 2001 and 2002 did not always lead to good survival and recruitment success. Even though their growth was slow in 2000, the larvae hatched early in the season had larger body size on a given date than faster-growing larvae hatched in later season in 2001 and 2002. Bigger individuals at a certain moment may have advantage for survival. The delay of hatching period may result in higher size-selective mortality, and as a necessary consequence, back-calculated growth in 2001 and 2002 could shift towards higher growth rate, although abundance of such a year class would be at the lower level. Variability in spawning period, early growth and their interaction might have a strong relation to larval survival through cumulative predation pressure or ontogenetic changes in food availability. [source] Effect of Drought Stress on Yield and Quality of Maize/Sunflower and Maize/Sorghum Intercrops for Biogas ProductionJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 4 2010S. SchittenhelmArticle first published online: 16 FEB 2010 Abstract Intercropping represents an alternative to maize (Zea mays L.) monoculture to provide substrate for agricultural biogas production. Maize was intercropped with either sunflower (Helianthus annuus L.) or forage sorghum [Sorghum bicolor (L.) Moench] to determine the effect of seasonal water supply on yield and quality of the above-ground biomass as a fermentation substrate. The two intercrop partners were grown in alternating double rows at plant available soil water levels of 60,80 %, 40,50 % and 15,30 % under a foil tunnel during the years 2006 and 2007 at Braunschweig, Germany. Although the intercrop dry matter yields in each year increased with increasing soil moisture, the partner crops responded quite differently. While maize produced significantly greater biomass under high rather than low water supply in each year, forage sorghum exhibited a significant yield response only in 2006, and sunflower in none of the 2 years. Despite greatly different soil moisture contents, the contribution of sorghum to the intercrop dry matter yield was similar, averaging 43 % in 2006 and 40 % in 2007. Under conditions of moderate and no drought stress, sunflower had a dry matter yield proportion of roughly one-third in both years. In the severe drought treatment, however, sunflower contributed 37 % in 2006 and 54 % in 2007 to the total intercrop dry matter yield. The comparatively good performance of sunflower under conditions of low water supply is attributable to a fast early growth, which allows this crop to exploit the residual winter soil moisture. While the calculated methane-producing potential of the maize/sorghum intercrop was not affected by the level of water supply, the maize/sunflower intercrop in 2006 had a higher theoretically attainable specific methane yield under low and medium than under high water supply. Nevertheless, the effect of water regime on substrate composition within the intercrops was small in comparison with the large differences between the intercrops. [source] Influence of Soil Temperature on Seedling Emergence and Early Growth of Peanut Cultivars in Field ConditionsJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 3 2006P. V. V. Prasad Abstract Peanut or groundnut (Arachis hypogaea L.) sown in early spring often has poor seed germination and seedling development. The influence of soil temperature on seedling emergence and early growth of six peanut cultivars (Florida MDR98, Southern Runner, Georgia Green, SunOleic 97R, Florunner and C-99R) was studied in natural field soil profiles in temperature-gradient greenhouses. We evaluated the influence of a range of soil temperatures by sowing at eight dates between January 2001 and May 2002 in Gainesville, Florida. On each sowing date, two additional temperature treatments (ambient and ambient +4.5 °C air temperature) were evaluated by sowing on either end of each greenhouse and applying differential heating. In total, 16 different soil temperature treatments were evaluated. Each treatment was replicated four times in four different greenhouses. Mean soil temperature from sowing to final emergence in different treatments ranged from 15 to 32 °C. Sowing date, temperature treatment and cultivar had significant effect on seedling emergence and development (V2 stage). For all cultivars, the lowest germination was observed at the earliest sowing date (coolest soil temperature). Among cultivars, Florida MDR98 was the most sensitive to reduced (cool) temperature with the lowest germination and smallest seedling size at 21 days after sowing, followed by Southern Runner. Georgia Green was the most cold-tolerant with the highest germination, followed by SunOleic 97R. There were no significant differences among cultivars for base temperature, which averaged 11.7 and 9.8 °C for rate of emergence and rate of development to V2 stage respectively. These results imply that cultivar choice and/or genetic improvement of peanut for cold tolerance during emergence and seedling development in regions where cooler soil temperatures persist and/or regions where early sowing is desirable. [source] Coupled Lu,Hf and Sm,Nd geochronology constrains garnet growth in ultra-high-pressure eclogites from the Dabie orogenJOURNAL OF METAMORPHIC GEOLOGY, Issue 7 2008H. CHENG Abstract Ultra-high-pressure eclogites from the Dabie orogen that formed over a range in temperatures (,600 to > 700 °C) have been investigated with combined Lu,Hf and Sm,Nd geochronology. Three eclogites, sampled from Zhujiachong, Huangzhen and Shima, yield Lu,Hf ages of 240.0 ± 5.0, 224.4 ± 1.9 and 230.8 ± 5.0 Ma and corresponding Sm,Nd ages of 222.5 ± 5.0, 217.6 ± 6.1 and 224.2 ± 2.1 Ma respectively. Well-preserved prograde major- and trace-element zoning in garnet in the Zhujiachong eclogite suggests that the Lu,Hf age mostly reflects an early phase of garnet growth that continued over a time interval of c. 17.5 Myr. For the Huangzhen eclogite, despite preserved elemental growth zoning in garnet, textural study reveals that the Lu,Hf age is biased towards a later garnet growth episode rather than representing early growth. The narrow time interval of <6.6 Myr defined by the difference between Lu,Hf and Sm,Nd ages indicates a short final garnet growth episode and suggests a rapid cooling stage. By contrast, the rather flat element zoning in garnet in the Shima eclogite suggests that Lu,Hf and Sm,Nd ages for this sample have been reset by diffusion and are cooling ages. The new Lu,Hf ages point to an initiation of prograde metamorphism prior to c. 240 Ma for the Dabie orogen, while the exact peak metamorphic timing experienced by specific samples ranges between c. 230 to c. 220 Ma. [source] Disturbance history of a European old-growth mixed-species forest,A spatial dendro-ecological analysisJOURNAL OF VEGETATION SCIENCE, Issue 5 2005Bernhard E. Splechtna Abstract Question: We were interested if and how variation in frequency and/or size of disturbances affect the dynamics of a montane old-growth forest in Central Europe. Location: The forest, co-dominated by Fagus sylvatica, Picea abies and Abies alba, is located in Lower Austria and represents one of the few sizable virgin forests in Central Europe. Methods: We extracted cores from 100 trees using systematic grid sampling (grid cell size 10 m × 10 m) on each of four 1-ha plots distributed across the old-growth remnant of 300 ha. We inferred disturbance events from rapid early growth and release events. For defining release criteria, we applied the boundary line method. We investigated the spatial structure of current age and gap distributions and past disturbance events in grid cells, using a pair density statistic. Results: The disturbance histories indicate decades with peaks and also extended periods without disturbance. Some peaks occurred synchronously at three of the four plots (1910s, 1930s, 1960s and 1980s). Peaks and gaps in the disturbance chronologies widely agreed with peaks and gaps in the age distributions. Most disturbance events during single decades showed a random spatial distribution. Conclusions: There is considerable variation in disturbance frequency and/or severity over time. Most disturbance events will rather thin the stand than clear larger areas at once. Following scattered disturbance two pathways occur: (1) gap expansion leading to creation of larger gaps, and (2) gap closure by lateral encroachment or by subcanopy trees growing into the canopy. [source] The influence of density on post-weaning growth in roe deer Capreolus capreolus fawnsJOURNAL OF ZOOLOGY, Issue 3 2002A. J. M. Hewison Abstract In temperate ungulates, the body weight of juveniles at the onset of winter is a crucial determinant of survival and can also influence subsequent reproductive success. However, growth may be retarded post-weaning, during winter, as a result of resource restriction and/or the demands of thermoregulation in harsh climatic conditions. Post-weaning growth rates of juveniles were compared in relation to varying density in two populations of roe deer Capreolus capreolus (Chizé, Dourdan) monitored for 10 and 15 years, respectively. Body growth of fawns continued over the post-weaning stage of the juvenile period (October,March) at the rate of 0.017 kg/day at Chizé and 0.014 kg/day at Dourdan. Deer density had no influence on this post-weaning growth rate of juveniles in their first winter. However, deer born in years of high density weighed less at a given date than those born in years of low density because of their smaller body size at the onset of winter, indicating density-dependent rates of growth before weaning. At Chizé, the sexes grew at the same rate, but sexual dimorphism was apparent as males weighed about 1 kg (8%) more than females at a given date. At Dourdan, no significant sexual dimorphism was detected, although females tended to be heavier than males at a given date. We conclude that density influences juvenile body weight (through its effect on birth weight and/or post-natal growth rate) before weaning in this species and, despite continued growth after weaning, during winter, roe deer whose early growth is limited through interspecific competition cannot compensate for this early restriction. [source] A size-mediated effect can compensate for transient chilling stress affecting maize (Zea mays) leaf extensionNEW PHYTOLOGIST, Issue 1 2010Gaëtan Louarn Summary ,In this study, we examined the impact of transient chilling in maize (Zea mays). We investigated the respective roles of the direct effects of stressing temperatures and indirect whorl size-mediated effects on the growth of leaves chilled at various stages of development. ,Cell production, individual leaf extension and final leaf size of plants grown in a glasshouse under three temperature regimes (a control and two short chilling transfers) were studied using two genotypes contrasting in terms of their architecture. ,The kinetics of all the leaves emerging after the stress were affected, but not all final leaf lengths were affected. No size-mediated propagation of an initial growth reduction was observed, but a size-mediated effect was associated with a longer duration of leaf elongation which compensated for reduced leaf elongation rates when leaves were stressed during their early growth. Both cell division and cell expansion contributed to explaining cold-induced responses at the leaf level. ,These results demonstrate that leaf elongation kinetics and final leaf length are under the control of processes at the n , 1 (cell proliferation and expansion) and n + 1 (whorl size signal) scales. Both levels may respond to chilling stress with different time lags, making it possible to buffer short-term responses. [source] Increased early growth rates decrease longevities of conifers in subalpine forestsOIKOS, Issue 8 2009Christof Bigler For trees, fast growth rates and large size seem to be a fitness benefit because of increased competitiveness, attainment of reproductive size earlier, reduction of generation times, and increased short-term survival chances. However, fast growth rates and large size entail reduced investment in defenses, lower wood density and mechanical strength, increased hydraulic resistance as well as problems with down-regulation of growth during periods of stress, all of which may decrease tree longevity. In this study, we investigated the relationship between longevity and growth rates of trees and quantified effects of spatial environmental variation (elevation, slope steepness, aspect, soil depth) on tree longevity. Radial growth rates and longevities were determined from tree-ring samples of 161 dead trees from three conifer species in subalpine forests of the Colorado Rocky Mountains (Abies lasiocarpa, Picea engelmannii) and the Swiss Alps (Picea abies). For all three species, we found an apparent tradeoff between growth rate to the age of 50 years and longevity (i.e. fast early growth is associated with decreased longevity). This association was particularly pronounced for larger P. engelmannii and P. abies, which attained canopy size, however, there were also significant effects for smaller P. engelmannii and P. abies. For the more shade-tolerant A. lasiocarpa, tree size did not have any effect. Among the abiotic variables tested only northerly aspect significantly favored longevity of A. lasiocarpa and P. engelmannii. Trees growing on south-facing aspects probably experience greater water deficits leading to premature tree death, and/or shorter life spans may reflect shorter fire intervals on these more xeric aspects. Empirical evidence from other studies has shown that global warming affects growth rates of trees over large spatial and temporal scales. For moist-cool subalpine forests, we hypothesize that the higher growth rates associated with global warming may in turn result in reduced tree longevity and more rapid turnover rates. [source] Influence of imidacloprid seed treatments on rice germination and early seedling growthPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 3 2008Mark M Stevens Abstract BACKGROUND: Seed treatments with the chloronicotinyl insecticide imidacloprid (Gaucho® 600 FS) were evaluated to determine whether differences in concentration and exposure regime influence the germination and early growth of rice. RESULTS: Continuous exposure to imidacloprid (4 days at 2000 mg AI L,1) significantly (P < 0.001) reduced normal germination by an average of 18% across the 15 cultivars examined. Nine days after sowing, plants showed no adverse effects from continuous imidacloprid treatment during germination, with shoot lengths and root system dry weights equalling, or occasionally exceeding (P < 0.05), those of untreated plants. Short-term imidacloprid exposure (2 h at 2000 mg L,1) at initial seed wetting did not affect germination (P > 0.05), and short-term (1 h) exposure of 48 h pregerminated seed to imidacloprid (2000 mg L,1) similarly had no significant effect on early subsequent growth. Plants arising from 48 h pregerminated seed exposed to imidacloprid (1 h) at concentrations up to 4000 mg L,1 immediately before sowing were not significantly different from control plants at either 9 or 25 days post-sowing. CONCLUSION: Results show that imidacloprid will have no adverse effects on plant growth if applied to pregerminated rice shortly before sowing. Continuous exposure of seed during germination had more pronounced effects, and the initial response of different cultivars was highly variable. Cultivars with high levels of sensitivity (such as IR72) require further testing before continuous exposure to imidacloprid during germination can be recommended. Copyright © 2007 Society of Chemical Industry [source] Growth in colony living anubis baboon infants and its relationship with maternal activity budgets and reproductive statusAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2009Cécile Garcia Abstract Early growth is of interest because it is susceptible to maternal effects and linked to fitness components for a range of species. Here we present anthropometric measurements on 23 infant olive baboons born into a captive colony in order to describe growth over the first 2 years of life, to explore maternal influences on growth, and to assess the impact of growth profiles on maternal reproduction. Six main findings emerged: 1) Infant growth rates in our colony were higher than those reported for wild populations but comparable to those observed for food-enhanced animals. 2) The ratio of infant mass to maternal mass was positively associated with reproductive parameters, such as duration of post-partum amenorrhea and interbirth interval. 3) Mothers resumed cycling and reconceived when their infants attained a relatively consistent threshold mass. 4) Infant mass-for-age was associated with maternal rank and, independently, with maternal mass such that females of high dominance rank and heavy females had relatively large infants at their resumption of cycling. 5) Low-ranking and lighter females had longer investment periods but smaller infants. They continued investment in infant through prolonged lactation until their infants reached a mass similar to that of infants of high-ranking/heavy mothers, suggesting that the lengthening of investment is essentially compensatory for slow early growth. 6) There was no relationship between infant growth and maternal activity budgets. Maternal physical and social factors, not energetics, contributed to differences among infants in growth trajectories, and infant growth temporally influenced successive reproductive events. Am J Phys Anthropol 2009. © 2008 Wiley-Liss, Inc. [source] Growth and developmental outcomes of three high-risk infant rhesus macaques (Macaca mulatta)AMERICAN JOURNAL OF PRIMATOLOGY, Issue 5 2007Amanda M. Dettmer Abstract Infants classified as "high risk" are born with a greater chance of developing medical complications at birth, and may have cognitive and other developmental complications later in life. Very few reports exist regarding the survival and outcome of such infants in primate colonies. Here we present early growth and developmental data on three high-risk infant rhesus macaques (one female and two males) that were born either with intrauterine growth restriction (IUGR; born below the 1st birth weight percentile for gestational age) or extremely prematurely (at gestational days 128 and 140; mean full-term gestation=164 days). We compared the outcome of these infants with that of healthy controls born at term and found no gross developmental delays in these infants with respect to growth, neonatal reflex and motor skill development, early cognitive development, or social behavior. Neurological and cognitive assessments were compared in terms of both postnatal and gestational age. The survival of these infants was dependent on a 24-hr staffed nursery and a fluid protocol that catered to each high-risk infant's individual needs. When such measures are implemented, infants such as these have a good chance of survival and can serve as excellent models for high-risk human babies and their subsequent development. Am. J. Primatol. 69:503,518, 2007. © 2007 Wiley-Liss, Inc. [source] Imaging the effects of castration on bone turnover and hormone-independent prostate cancer colonization of boneTHE PROSTATE, Issue 15 2008N.A. Cross Abstract INTRODUCTION Tumor populations may selectively colonize bone that is being actively remodeled. In prostate cancer patients, androgen deprivation directly inhibits tumor growth initially, whilst induced bone loss may facilitate tumor colonization of bone by androgen-insensitive cells. We have tested this hypothesis using a xenograft model of early growth of prostate cancer in bone. METHODS PC3 cells transfected with Green fluorescent protein (GFP) were injected into castrated and non-castrated athymic mice via intrabial and intracardiac routes. In vivo tumor growth was monitored daily and animals sacrificed 6,9 days following initial GFP-based detection of tumors. Tumor bearing and contra-lateral non-tumor bearing tibias were analyzed extensively by micro-CT and histology/immunohistochemistry for the presence of tumor cells and the effects of tumor and/or castration on bone cells and bone structure evaluated. RESULTS GFP-positive tumors in bone were visible from 12 days post-injection following intratibial injection, allowing tumors <1 mm diameter to be monitored in live animals. Castration did not affect tumor frequency, tumor volume, or time to initial appearance of tumors injected via intratibial or intracardiac routes. Castration decreased trabecular bone volume in all mice. Significant tumor-induced suppression of numbers of osteoblasts, coupled with increased numbers of activated osteoclasts, was evident in both intact animals and castrated animals. CONCLUSIONS In vivo GFP imaging allows the detection of early tumor growth at intra-osseous sites. Castration induces bone loss, but PC3-GFP cells are also capable of inducing bone remodeling in intact animals at early time points, independently of pre-existing castration-induced alterations to bone. Prostate 68: 1707,1714, 2008. © 2008 Wiley-Liss, Inc. [source] Estimation of dominance genetic variances for reproductive traits and growth traits of calves in Japanese Black cattleANIMAL SCIENCE JOURNAL, Issue 4 2004Takafumi ISHIDA ABSTRACT The dominance genetic effects for reproductive and calf growth abilities in the practical Japanese Black populations were examined using average information (AI) algorithm restricted maximum likelihood (REML) under animal models. The reproductive traits were observed in Japanese Black cattle maintained at Tottori and Okinawa prefectures, and growth traits of calves were observed in cattle at Okinawa. The average of dominance relationships in Tottori ranged from 0.2 to 0.4%, while the level in Okinawa was lower and sparse compared with Tottori. The proportions of the dominance variances to sum of additive and dominance variances () were all 0.02 for reproductive traits in Tottori. In contrast, the proportion was 0.02,0.64 in Okinawa regardless of the level of dominance relationships. These proportions suggested that the dominance might affect the expression of calving interval, days open and gestation length in Okinawa, where breeding units were spread over many islands. Although the dominance variances could not estimate birthweight, w as 0.34 for calf market weight and 0.27 for average daily gain from birth to calf market in Okinawa. These values also suggested that the dominance might affect the early growth of calves. In the near future, genetic relationships will become more complicated with continuation of the current selection and mating systems. Therefore, genetic evaluation accounting for dominance effects would be necessary for particular traits and populations. [source] Sustainable production of crops and pastures under drought in a Mediterranean environmentANNALS OF APPLIED BIOLOGY, Issue 2 2004NEIL C TURNER Summary Mediterranean environments are characterised by cool wet winters and hot dry summers. While native vegetation in Mediterranean-climatic zones usually comprises a mixture of perennial and annual plants, agricultural development in the Mediterranean-climatic region of Australia has led to the clearing of the perennial vegetation and its replacement with annual crops and pastures. In the Mediterranean environments of southern Australia this has led to secondary (dryland) salinisation. In order to slow land degradation, perennial trees and pasture species are being reintroduced to increase the productivity of the saline areas. The annual crops and pastures that form the backbone of dryland farming systems in the Mediterranean-climatic zone of Australia are grown during the cool wet winter months on incoming rainfall and mature during spring and early summer as temperatures and rates of evaporation rise and rainfall decreases. Thus, crop and pasture growth is usually curtailed by terminal drought. Where available, supplementary irrigation in spring can lead to significant increases in yield and water use efficiency. In order to sustain production of annual crops in Mediterranean environments, both agronomic and genetic options have been employed. An analysis of the yield increases of wheat in Mediterranean-climatic regions shows that there has generally been an increase in the yields over the past decades, albeit at a lower rate than in more temperate regions. Approximately half of this increase can be attributed to agronomic improvements and half to genetic improvements. The agronomic improvements that have been utilised to sustain the increased yields include earlier planting to more closely match crop growth to rainfall distribution, use of fertilisers to increase early growth, minimum tillage to enable earlier planting and increase plant transpiration at the expense of soil evaporation, rotations to reduce weed control and disease incidence, and use of herbicides, insecticides and fungicides to reduce losses from weeds, insects and disease. Genetic improvements include changing the phenological development to better match the rainfall, increased early vigour, deeper rooting, osmotic adjustment, increased transpiration efficiency and improved assimilate storage and remobilisation. Mediterranean environments that are subjected annually to terminal drought can be both environmentally and economically sustainable, but to maximise plant water use efficiency while maintaining crop productivity requires an understanding of the interaction between genotypes, environment and management. [source] Evaluation of fungal antagonists for grey mould management in early growth of pot rosesANNALS OF APPLIED BIOLOGY, Issue 1 2004D S YOHALEM Summary Several filamentous fungi can reduce disease incidence and suppress sporulation of Botrytis cinerea during early establishment and vegetative growth of pot roses. Two isolates of Ulocladium atrum were the most successful of those fungi tested, were consistently more effective than the fungicide, iprodione and not different from each other. Tween 80, added as a dispersant, had no effect on the efficacy of U. atrum. An isolate of Clonostachys rosea also gave better disease control than iprodione, although not to the levels given by isolates of U. atrum, nor was its behaviour consistent across experiments. Another isolate of C. rosea performed well in one trial, had no discernible effect in a second and was excluded from the third due to poor inoculum quality. Commercial Trichoderma harzianum preparations (Trichodex and Supresivit) failed to reduce disease incidence under the high disease pressure of these experiments, but did reduce sporulation of the pathogen relative to untreated controls. [source] A comparison among differently enriched rotifers (Brachionus plicatilis) and their effect on Atlantic cod (Gadus morhua) larvae early growth, survival and lipid compositionAQUACULTURE NUTRITION, Issue 1 2008A.S. GARCIA Abstract We evaluated the effect of differently enriched rotifers on the early growth, survival and lipid composition of Atlantic cod larvae (Gadus morhua). The enrichments tested were: (i) AlgaMac 2000®; (ii) AquaGrow® Advantage; and (iii) a combination of Pavlova sp. paste and AlgaMac 2000®. Larvae from treatment 3 [1.50 ± 0.11 mg dry weight (dw) and 7.10 ± 0.14 dw specific growth rate (SGR)] were heavier (P = 0.006) and grew faster (P = 0.004) than larvae from treatment 2 (1.03 ± 0.04 mg dw and 6.29 ± 0.04 dw SGR). No significant differences were found in the final weight and SGR among larvae from treatment 1 (1.21 ± 0.07 mg dw and 6.58 ± 0.20 dw SGR) and larvae from treatments 2 and 3. The treatment 3 also resulted in the best survival at the end of the experimental period, estimated to be 3 on a scale from 1 to 5, whereas the survival estimates for the two other groups were 1,2. Larvae from the treatment 3 reached 37 days posthatch with levels of ,6DPA 32-fold higher than newly hatched larvae. Differences in the larval enrichment of ,6DPA may explain the differences in growth and survival of the Atlantic cod larvae. [source] The effect of soil compaction on germination and early growth of Eucalyptus albens and an exotic annual grassAUSTRAL ECOLOGY, Issue 6 2009ALISON K. SKINNER Abstract Most agricultural land has been compacted to some degree by heavy machinery or livestock trampling. This legacy is expected to influence the success of tree seedling recruits in farmland areas where natural regeneration is being encouraged. We investigated the impact of soil compaction on seedlings of a woodland eucalypt (Eucalyptus albens) and an annual grass competitor (Vulpia myuros) in a laboratory experiment. Replicate soil cores were created at five bulk density levels; 1.0, 1.1, 1.2, 1.3 or 1.4 Mg m,3 with a soil water content of 20%. The depth of root penetration declined linearly with increasing bulk density, resulting in a decrease in root depth of around 75% in the most compacted soil compared with the least compacted soil for both species. Shoot length and primary root length did not vary between soil bulk density levels for either species, but seedlings responded to increasing levels of compaction with oblique (non-vertical) root growth. Results suggest that young seedlings of both E. albens and V. myuros will be more susceptible to surface drying in compacted than uncompacted soils and therefore face a greater risk of desiccation during the critical months following germination. Any competitive advantage that V. myuros may have over E. albens is not evident in differential response to soil compaction. [source] Acceleration of germination and early growth of wheat and bean seedlings grown under various magnetic field and osmotic conditionsBIOELECTROMAGNETICS, Issue 2 2010Turgay Cakmak Abstract Magnetic field (MF) can have different effects on plant metabolism depending on its application style, intensity, and environmental conditions. This study reports the effects of different intensities of static MF (4 or 7,mT) on seed germination and seedling growth of bean or wheat seeds in different media having 0, 2, 6, and 10 atmosphere (atm) osmotic pressure prepared with sucrose or salt. The germination percentages of the treated seeds were compared with untreated seeds germinated in different osmotic pressure during 7 days of incubation. The application of both MFs promoted the germination ratios of bean and wheat seeds, regardless of increasing osmotic pressure of sucrose or salt. Growth data measured on the 7th day showed that the treated plants grew faster than control. After 7 days of incubation, the mean length of treated seedlings was statistically higher than control plants in all the media. The greatest germination and growth rates in both plants were from the test groups exposed to 7,mT MF. Strikingly, effects of static MF on germination and growth increased positively with increasing osmotic pressure or salt stress compared to their respective controls. On the other hand, MF application caused an increase in dry biomass accumulation of root and shoots of both seedlings; however, this effect was found statistically important in all the conditions for wheat but not for bean, in general. Bioelectromagnetics 31:120,129, 2010. © 2009 Wiley-Liss, Inc. [source] Effects of a 60 Hz magnetic field on photosynthetic CO2 uptake and early growth of radish seedlingsBIOELECTROMAGNETICS, Issue 8 2004Akira Yano Abstract Photosynthetic CO2 uptake rate and early growth parameters of radish Raphanus sativus L. seedlings exposed to an extremely low frequency magnetic field (ELF MF) were investigated. Radish seedlings were exposed to a 60 Hz, 50 ,Trms (root mean square) sinusoidal magnetic field (MF) and a parallel 48 ,T static MF for 6 or 15 d immediately after germination. Control seedlings were exposed to the ambient MF but not the ELF MF. The CO2 uptake rate of ELF MF exposed seedlings on day 5 and later was lower than that of the control seedlings. The dry weight and the cotyledon area of ELF MF exposed seedlings on day 6 and the fresh weight, the dry weight and the leaf area of ELF MF exposed seedlings on day 15 were significantly lower than those of the control seedlings, respectively. In another experiment, radish seedlings were grown without ELF MF exposure for 14 d immediately after germination, and then exposed to the ELF MF for about 2 h, and the photosynthetic CO2 uptake rate was measured during the short term ELF MF exposure. The CO2 uptake rate of the same seedlings was subsequently measured in the ambient MF (control) without the ELF MF. There was no difference in the CO2 uptake rate of seedlings exposed to the ELF MF or the ambient MF. These results indicate that continuous exposure to 60 Hz, 50 ,Trms sinusoidal MF with a parallel 48 ,T static MF affects the early growth of radish seedlings, but the effect is not so severe that modification of photosynthetic CO2 uptake can be observed during short term MF exposure. Bioelectromagnetics 25:572,581, 2004. © 2004 Wiley-Liss, Inc. [source] One-year follow-up of a lentigo maligna: first dermoscopic signs of growthBRITISH JOURNAL OF DERMATOLOGY, Issue 5 2004R. Schiffner Summary We report a 64-year-old man with a pigmented lesion on his forehead, initially thought to be actinic lentigo. At follow-up 1 year later the lesion had increased in size and showed new areas of pigmentation. Dermoscopic observation and biopsy led to a diagnosis of lentigo maligna and the lesion was excised. The dermoscopic features indicative of early growth of lentigo maligna are identified and discussed. [source] Early postnatal growth variables are related to morphologic and functional ophthalmologic outcome in children born pretermACTA PAEDIATRICA, Issue 5 2010M Hök-Wikstrand Abstract Aim:, To evaluate the association between gestational age (GA), early and late postnatal growth variables and ophthalmologic outcome in ex-preterm children. Methods:, Children (GA < 32 weeks, n = 66), previously examined regarding insulin-like growth factor 1 (IGF-1) serum concentrations in relation to ROP, underwent ophthalmologic examination at median 5.6 years. Weight, height, and head circumference (HC) were measured and expressed as SDS. Growth variables were analysed in relation to ophthalmologic outcome. Results:, At follow-up 74% had some ophthalmologic abnormality and 17% had visual impairment. Poor visual acuity was correlated with low GA (rs = 0.29, p = 0.019), low weight at 32 weeks (rs = 0.30, p = 0.013), and low weight (rs = 0.37, p = 0.0025), height (rs = 0.41, p = 0.0007) and HC (rs = 0.55, p < 0.0001) at follow-up. Hyperopic children (25%) had low neonatal IGF-1 (p = 0.0096) and HC at follow-up (p = 0.022). Poor visual perception was correlated with low early weight (rs = 0.38, p = 0.0036) and HC at follow-up (rs = 0.39, p = 0.0024). Head circumference at follow-up was correlated with GA (rs = 0.40, p = 0.0012), neonatal IGF-1 (rs = 0.37, p = 0.0031), and early weight (rs = 0.27, p = 0.035). Conclusions:, In very preterm children, early and later postnatal growth is closely related to visual acuity and perception at follow-up. In addition, IGF-1 concentrations and early growth are correlated with head circumference and refraction at follow-up. [source] | ||||||||||||||||||||||||||||