Growth and Development of Pouch Young of the Stripe-faced Dunnart, Sminthopsis macroura (Marsupialia : Dasyuridae), in Captivity

1997 ◽  
Vol 45 (2) ◽  
pp. 157 ◽  
Author(s):  
L. Frigo ◽  
P. A. Woolley
Keyword(s):  
Growth Rate ◽  
Phase Ii ◽  
Growth And Development ◽  
Post Partum ◽  
Growth Curves ◽  
Colony Growth ◽  
Preliminary Evidence ◽  
Mammary Tissue ◽  
Relative Growth ◽  
Sminthopsis Macroura

The growth and development of the stripe-faced dunnart, Sminthopsis macroura (Gould), a small insectivorous marsupial, was examined and described from birth to weaning (a period of 65–70 days). All observations and analyses were based on known-age individuals from a laboratory colony. Growth curves showing the regression of body weight, head, pes, crown–rump, tail and head+body lengths as a function of age were constructed. Relative growth was determined by calculating the instantaneous relative growth rate, k, and two major phases of growth were recognised: during Phase I (birth to about Day 54 post partum) growth rate was rapid, and during Phase II (about Day 55 to weaning) a deceleration in growth rate was apparent. Growth rate may decline because of regression of the mammary tissue associated with the commencement of weaning. No significant relationship was found between month of birth and growth rate, and preliminary evidence suggests that litters of different sizes may grow at varying rates during Phase II of the suckling period. Preserved and living specimens were used to examine the development of young from birth to weaning.

The effect of nursery substrate and fertilization on the growth and ectomycorrhizal status of containerized and outplanted seedlings of Picea abies

2009 ◽  
Vol 39 (1) ◽  
pp. 64-75 ◽  
Author(s):  
Lu-Min Vaario ◽  
Arja Tervonen ◽  
Kati Haukioja ◽  
Markku Haukioja ◽  
Taina Pennanen ◽  
...  
Keyword(s):  
Growth Rate ◽  
Picea Abies ◽  
Norway Spruce ◽  
Growth And Development ◽  
Organic Fertilizer ◽  
Wood Fibre ◽  
Organic Fertilizers ◽  
Relative Growth ◽  
Ecm Fungi ◽  
Influence Of Substrate

Over a 5 year period, we examined the influence of substrate and fertilization on nursery growth and outplanting performance of Norway spruce (Picea abies (L.) Karst.). We focused on the relative growth and development of roots and shoots and the colonization intensity and diversity of ectomycorrhizal (ECM) fungi. In the nursery, a conventional substrate (low-humified Sphagnum peat) supplemented with woody material (wood fibre and pine bark) and either mineral or organic fertilizers yielded shorter seedlings than those grown on the unmodified substrate. However, after outplanting, the growth rate of seedlings cultivated on modified substrates was higher than that of seedlings grown on the unmodified substrate. Seedlings cultivated in modified substrates had significantly higher root/shoot ratios and ECM diversity; the latter remained significant after ≥3 years of outplanting. Seedlings grown on a substrate containing 50% woody material and supplemented with organic fertilizer had the highest growth rate among all seedlings during the 3 year period of outplanting. Colonization intensity of ECM fungi was high in all seedlings except for those grown in heavily fertilized substrate. This study suggests that nursery techniques that produce seedlings with higher root/shoot ratios and ECM diversities could improve plantation success and growth rate for at least the first 3 years of outplanting.

Growth and Development of Organic Arsenical-Susceptible and -Resistant Common Cocklebur (Xanthium strumarium) Biotypes Under Noncompetitive Conditions

1994 ◽  
Vol 8 (1) ◽  
pp. 154-158 ◽  
Author(s):  
William E. Haigler ◽  
Billy J. Gossett ◽  
James R. Harris ◽  
Joe E. Toler
Keyword(s):  
Growth Rate ◽  
Leaf Area ◽  
Plant Height ◽  
Growth And Development ◽  
Reproductive Potential ◽  
Dry Weight ◽  
Growing Season ◽  
Xanthium Strumarium ◽  
Relative Growth ◽  
Growth Development

The growth, development, and reproductive potential of several populations of organic arsenical-susceptible (S) and -resistant (R) common cocklebur biotypes were compared under noncompetitive field conditions. Plant height, leaf area, aboveground dry weights, and relative growth rate (RGR) were measured periodically during the growing season. Days to flowering, bur dry weight, and number of burs per plant were also recorded. Arsenical S- and R-biotypes were similar in all measured parameters of growth, development, and reproductive potential. Populations within each biotype varied occasionally in plant height, leaf area, aboveground dry weights, and reproductive potential.

Effect of Photoperiod on Growth and Development of Cassava (Manihot esculenta Crantz)

1985 ◽  
Vol 12 (6) ◽  
pp. 621 ◽  
Author(s):  
BA Keating ◽  
GL Wilson ◽  
JP Evenson
Keyword(s):  
Growth Rate ◽  
Relative Growth Rate ◽  
Growth And Development ◽  
Day Treatment ◽  
Storage Root ◽  
Storage Roots ◽  
Manihot Esculenta Crantz ◽  
Dry Matter Partitioning ◽  
Relative Growth ◽  
Controlled Environments

Effects of photoperiod on growth and development of cassava were studied in controlled environments. Plants of cultivars M Aus 7 and M Aus 10 were grown under short (10-h) and long (16-h) photoperiods and harvested at approximately weekly intervals for a period of 13 weeks. Long photoperiods resulted in large increases in leaf area through increases in both number (both cultivars) and size of leaves (M Aus 7 only). The timing, extent and anatomical characteristics of storage root initiation were similar for both cultivars under 10-h and 16-h photoperiods but the subsequent balance between shoot and storage root growth strongly favoured shoot growth in long days. Dry matter partitioning followed a simple allometric pattern with the proportionality between the relative growth rate of shoots and the relative growth rate of storage roots remaining constant with time but being altered by photoperiod. Distribution to storage roots was quantitatively reduced in another experiment using M Aus 10 with each additional 1-h increment from 10-h to 16-h photoperiods. A treatment consisting of a short day (10 h) plus a 1-h night break in the middle of the dark period produced growth similar to long day treatment. Differences in cultivar response (Ceiba, CMC 84 and M Aus 7) to a range of photoperiods (11, 12, 13 and 14 h) were detected in a third experiment. The possible mechanisms and significance of these responses are discussed.

scholarly journals Error estimation in plant growth analysis

2014 ◽  
Vol 65 (3-4) ◽  
pp. 207-212 ◽  
Author(s):  
Andrzej Gregorczyk
Keyword(s):  
Growth Rate ◽  
Plant Growth ◽  
Growth Analysis ◽  
Growth Curves ◽  
Logistic Function ◽  
Relative Growth ◽  
Unit Leaf ◽  
Joint Application ◽  
Richards Function ◽  
Maize Plants

The scheme is presented for calculation of errors of dry matter values which occur during approximation of data with growth curves, determined by the analytical method (logistic function) and by the numerical method (Richards function). Further formulae are shown, which describe absolute errors of growth characteristics: Growth rate (GR), Relative growth rate (RGR), Unit leaf rate (ULR) and Leaf area ratio (LAR). Calculation examples concerning the growth course of oats and maize plants are given. The critical analysis of the estimation of obtained results has been done. The purposefulness of joint application of statistical methods and error calculus in plant growth analysis has been ascertained.

scholarly journals Rape embryogenesis. III. Embryo development in time

2014 ◽  
Vol 49 (4) ◽  
pp. 369-385 ◽  
Author(s):  
Teresa Tykarska
Keyword(s):  
Growth Rate ◽  
Phase I ◽  
Phase Ii ◽  
Apical Cell ◽  
Phase Iii ◽  
Development Phase ◽  
Embryo Axis ◽  
Intensity Maximum ◽  
Relative Growth ◽  
Growth Intensity

It was found that the growth curve of the rape embryo axis is of triple sigmoid type. Embryo growth occurs in 3 phases corresponding to 3 different periods of development. Phase I includes growth of the apical cell up to it's division into two layers of octants. Phase II comprises the increase of the spherical proembryo to the change of its symmetry from radial to bilateral. Phase III includes, growth of the embryo from the heart stage up to the end of embryogenesis. In each phase the relative growth rate increases drastically and then diminishes. The differences in growth intensity during the same phase are several-fold. The growth intensity maximum of the embryo axis occurs in phase II. The phasic growth intensity maxima occur: in phase I during apical cell elongation, :before its division, and in phases II and III in the periods of cell division ;growth in globular and torpedo-shaped -shaped embryos.

La première feuille des plantules d'orge. II. Croissance en longueur

1982 ◽  
Vol 60 (12) ◽  
pp. 2877-2881 ◽  
Author(s):  
A. Silvy
Keyword(s):  
Growth Rate ◽  
Relative Growth Rate ◽  
Growth Curve ◽  
Growth Curves ◽  
Relative Growth ◽  
Leaf Initiation ◽  
Line Breeding ◽  
The Moment

The growth in length, of the first leaf was studied after an improvement by line breeding and seed grading. Similar to leaf initiation which occurs in two distinct periods for the blade and for the sheath, the growth curve of the whole leaf equals the sum of the growth curves for the blade and for the sheath, respectively. The relative growth rate for the whole leaf reaches a maximum, then decreases with a shoulder. The maximum corresponds to the greatest relative growth rate for the blade. The change in the rate of decrease corresponds to the beginning of the sheath growth at the moment when the blade is emerging.

Sexual maturity and related phenomena in the domestic fowl

1955 ◽  
Vol 46 (1) ◽  
pp. 9-18 ◽  
Author(s):  
E. S. E. Hafez ◽  
G. A. R. Kamar
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Domestic Fowl ◽  
Sexual Maturity ◽  
Growth Curves ◽  
Effect Of Temperature ◽  
Relative Growth ◽  
Heavy Body ◽  
June July ◽  
Autumn And Winter

Three hundred and eighty-two Fayomi pullets were available from different hatches throughout the year. The age and body weight, as well as the weight of first eggs at sexual maturity in relation to growth curves, were recorded. The fertilizability and hatchability of the first eggs laid at sexual maturity were also examined from one hundred pullets hatched during the months of November and August.1. (a) The winter hatches (December, January and February) reached sexual maturity at 183 days and at a body weight of 1093 g. The weight of the first ten eggs was 31·8 g., while the period from first to the tenth egg was 26 days. Summer hatches (June, July and August) reached sexual maturity at 165 days and at a body weight of 1124 g., while the weight of the first ten eggs was 32·4 g. and the period from first to tenth egg was 31 days. Autumn hatches (September, October and November) reached sexual maturity at 159 days and at a body weight of 1023 g., while the weight of the first ten eggs was 31·4 g. and the period from first to tenth egg was 23 days.(b) Summer and winter hatches attained sexual maturity at an older age and heavier body weight, and laid heavier first ten eggs in a longer period than autumn hatches.2. The growth curves were higher for the summer hatches than for the spring (March, April and May) ones. Winter and autumn hatches were intermediate. Summer hatches attained sexual maturity at a higher relative growth rate than autumn and winter hatches. In Egypt (30° N.), the effect of temperature seems to override that of daylength in respect to growth and sexual maturity.3. Yearly differences in the attainment of sexual maturity were significant, mainly in December hatches. Individual differences were minimized during summer hatches.4. (a) The first egg laid can be fertilizable and even hatchable. When sexual maturity was attained at an old age or a heavy body weight, the first eggs laid had a greater chance of being fertilizable and hatchable. This is due to the weight of first eggs laid and to the season at which sexual maturity is attained.(b) The attainment of sexual maturity as measured by the fertilizability and hatchability of first eggs, seems to be a gradual phenomenon.

An analysis of the growth of silver maple and eastern cottonwood seedlings exposed to ozone

1982 ◽  
Vol 12 (2) ◽  
pp. 420-424 ◽  
Author(s):  
K. F. Jensen
Keyword(s):  
Growth Rate ◽  
Leaf Area ◽  
Growth Parameters ◽  
Growth Curves ◽  
Relative Growth ◽  
Eastern Cottonwood ◽  
Silver Maple ◽  
Leaf Weight ◽  
Net Assimilation ◽  
Species Specific

Silver maple (Acersaccharinum L.) and eastern cottonwood (Populusdeltoides Bartr.) seedlings were treated with either 0.0, 0.1, 0.2, or 0.3 ppm ozone for 12 h/day for up to 60 consecutive days. Six seedlings were harvested from each treatment at 10-day intervals to construct growth curves for leaf area, leaf weight, and stem plus leaf weight. Relative growth parameters were calculated from these curves. Relative growth rate, relative leaf-area growth rate, and relative leaf-weight growth rate declined with an increase in time and ozone concentration. Net assimilation rate declined with time in both species. Specific leaf area and leaf-area ratio had no consistent trends.

scholarly journals THE GROWTH AND ABSORPTION OF NUTRIENTS BY FERTILIZED AND UNFERTILIZED WHITE SPRUCE SEEDLINGS

1966 ◽  
Vol 42 (2) ◽  
pp. 127-136 ◽  
Author(s):  
K. A. Armson
Keyword(s):  
Growth Rate ◽  
Growth And Development ◽  
Dry Weight ◽  
Growing Season ◽  
White Spruce ◽  
Height Growth ◽  
Relative Growth ◽  
Uptake Rates ◽  
Abrupt Changes ◽  
Growth Development

A study was made of the effects of fertilizer additions on the growth and development of white spruce seedlings during their second growing season. In terms of dry weight increment, unfertilized trees grew for only two-thirds of the total growing season available as compared with fertilized trees. The relative growth rate curve for the fertilized trees was smooth with none of the abrupt changes which marked the curve for the unfertilized trees. The pattern of height growth was changed for seedlings which were fertilized. Nutrient uptake rates particularly for phosphorus were different under the two treatments and it is suggested that these differences were related to different patterns of height growth development and root extension.

scholarly journals Cool-season Turfgrass Color and Growth Habit Response to Elevated Levels of Ultraviolet-B Radiation

HortScience ◽  
2016 ◽  
Vol 51 (4) ◽  
pp. 439-443 ◽  
Author(s):  
Edward J. Nangle ◽  
David S. Gardner ◽  
James D. Metzger ◽  
Dominic P. Petrella ◽  
Tom K. Danneberger ◽  
...  
Keyword(s):  
Growth Rate ◽  
Perennial Ryegrass ◽  
Tall Fescue ◽  
Growth And Development ◽  
Treatment Initiation ◽  
Creeping Bentgrass ◽  
Ultraviolet B ◽  
Cool Season ◽  
Relative Growth ◽  
Ultraviolet B Radiation

Ultraviolet (UV) radiation poses a potential stress for plant growth and development due to its effect on photosynthesis and plant productivity. In the northern hemisphere, peak UV radiation exposure is predicted to occur from 2010 to 2020, with reduced color from UV-related injury, a possibility for turfgrasses. The objective of this study was to investigate the effects of ultraviolet-B (UV-B) light on turfgrass growth and morphology in three cool-season grasses. Cultivars Barvado tall fescue [Schedonorus arundinaceus (Schreb.) Dumort., nom. cons.], Penncross and L-93 creeping bentgrass (Agrostis stolonifera L.), and Barlenium perennial ryegrass (Lolium perenne L.), were selected because of limited information on their growth and development in elevated UV conditions at heights of cut above 10 cm. The impact of UV-B light treatment on color, relative growth rate, and tillering was measured over a 4-week period in repeated experiments. Ultraviolet-B radiation levels were measured at 16 kJ·m−2·d−1 biologically effective UV-B light in growth chambers programmed for a day/night regime of 14/10 hours. Chamber temperatures were maintained at 20 °C day/17 °C night. Ultraviolet-B light significantly inhibited tiller production in the first experiment in all grasses except PR, whereas no grasses were inhibited in the second experiment. Relative growth rates in all grasses were significantly lower in UV-B conditions 3 weeks after treatment initiation. Turfgrasses exposed to this level of UV-B light at typical lawn heights-of-cut had lower color ratings compared with the non-UV-B-treated control at 2 weeks after treatment initiation. The experiments demonstrated that exposure to UV-B resulted in a decline of growth rate and color in cool-season turfgrasses within a timeframe of 2 weeks. Coarse-textured turfgrasses [tall fescue (TF)/perennial ryegrass (PR)] may be more adapted to higher UV-B conditions due to morphological differences compared with the finer textured varieties [creeping bentgrass (CB)].

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