Optimizing growth and development of 2-0 Douglas-fir seedlings by altering light intensity

1983 ◽  
Vol 13 (3) ◽  
pp. 425-428 ◽  
Author(s):  
Allan P. Drew
Keyword(s):  
Light Intensity ◽  
Root Development ◽  
Growth And Development ◽  
Dry Matter ◽  
Dry Weight ◽  
Growing Season ◽  
Douglas Fir ◽  
Total Weight ◽  
Planting Stock

Douglas-fir (Pseudotsitgamenziesii (Mirb.) Franco) seedlings were grown outdoors in pots under 71% of full light the first growing season and full light the second. Another group of seedlings was given full light continuously for 2 years. At the end of the 1st year, seedlings given initial shade had grown larger in total weight (root + shoot) than those grown under full light. With removal of shading, the larger plants with lower shoot/root ratios began to allocate increased dry matter to root development relative to their shoots. By the end of 2 years, shoot/root ratios for the two groups were no different, yet the plants shaded in their 1st year were 69% larger in dry weight. By proper use of shading during development, larger 2-0 planting stock having good root development may be produced. Such stock, grown without the use of costly fertilizer, may be better suited to regeneration of droughty sites in the Northwest than the usual 2-0 planting stock, nursery grown under full light.

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.

Effects of Temperature and Photoperiod on Texas Panicum (Panicum texanum) and Wild Proso Millet (Panicum miliaceum)

Weed Science ◽  
1986 ◽  
Vol 34 (6) ◽  
pp. 876-882 ◽  
Author(s):  
David T. Patterson ◽  
Ann E. Russell ◽  
David A. Mortensen ◽  
Robert D. Coffin ◽  
Elizabeth P. Flint
Keyword(s):  
United States ◽  
Vegetative Growth ◽  
Dry Matter ◽  
Dry Weight ◽  
Growing Season ◽  
Southern United States ◽  
Panicum Miliaceum ◽  
Proso Millet ◽  
Effects Of Temperature ◽  
Total Dry Weight

Texas panicum (Panicum texanumBuckl. # PANTE) is a native of the Southwest, now increasing as a weed throughout the southern United States, whereas wild proso millet (Panicum miliaceumL. # PANMI) is an introduced weed currently increasing in importance in the northern Midwest. In controlled-environment chambers, both species produced more tillers, greater leaf area, and more total dry weight at 30/24 C day/night (simulated growing season temperature in Georgia) than at 24/18 C (simulated growing season temperature in Minnesota). Texas panicum accumulated more dry matter at 30/24 C than did wild proso millet, while wild proso millet accumulated more dry matter at 24/18 C than did Texas panicum. When the two species were grown together, Texas panicum was the superior competitor at 30/24 C while wild proso millet was superior at 24/18 C. Exposure to short photoperiods at an intermediate temperature of 27/21 C accelerated flowering and limited vegetative growth in both species. In the range of photoperiods (10 to 16 h) examined, wild proso millet always flowered earlier and, consequently, produced less vegetative growth than Texas panicum. Its responses to temperature and photoperiod indicate that wild proso millet probably would be competitively inferior to Texas panicum and other adapted grass weeds in the southern United States.

Copper nutrition of subterranean clover (Trifolium subterraneum L. cv. Seaton Park). I. Effects of copper supply on growth and development

1981 ◽  
Vol 32 (2) ◽  
pp. 257 ◽  
Author(s):  
DJ Reuter ◽  
AD Robson ◽  
JF Loneragan ◽  
DJ Tranthim-Fryer
Keyword(s):  
Root Growth ◽  
Growth And Development ◽  
Copper Deficiency ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Dry Weight ◽  
Growing Season ◽  
Internode Elongation ◽  
Plant Parts ◽  
Lateral Branches

Effects of severe and moderate copper deficiency on the development of leaves and lateral branches, on the distribution of dry weight within the plant, and on seed yield of Seaton Park subterranean clover were assessed as part of three glasshouse experiments. Copper deficiency markedly depressed top and root growth without producing any distinctive symptoms. It retarded phasic development by delaying development of leaves and lateral branches, senescence of plant parts, and flowering: it also depressed the proportion of stem plus petiole in plant tops and decreased internode elongation, pollen fertility and the number of burrs and seeds formed. As a result of its effect in delaying flowering, copper deficiency would depress seed production particularly strongly when low soil water supply shortens the growing season. The need for suitable procedures for diagnosing copper deficiency is emphasized by the lack of specific plant symptoms in this species.

Growth and Development of Dinitroaniline-Susceptible and -Resistant Goosegrass (Eleusine indica) Biotypes Under Noncompetitive Conditions

Weed Science ◽  
1986 ◽  
Vol 34 (5) ◽  
pp. 704-710 ◽  
Author(s):  
Tim R. Murphy ◽  
Billy J. Gossett ◽  
Joe E. Toler
Keyword(s):  
Growth And Development ◽  
Growth Parameters ◽  
Flag Leaf ◽  
Dry Weight ◽  
Growing Season ◽  
Leaf Length ◽  
Relative Growth ◽  
Eleusine Indica ◽  
Flag Leaf Length ◽  
Weight Number

A comparative study of the growth and development of several populations of dinitroaniline-susceptible (DS) and -resistant (DR) goosegrass [Eleusine indica(L.) Gaertn. # ELEIN] biotypes was conducted under noncompetitive field conditions. Plant height and width, number of tillers, aboveground dry weight, relative growth rate (RGR), number of inflorescences/plant, total inflorescence dry weight, individual inflorescence dry weight, number of spicate branches/inflorescence, and flag leaf length and width were recorded periodically during the growing season. There were no significant differences between biotypes in most characteristics with the exception of total inflorescence dry weight. The DS biotype produced more total inflorescence dry weight than the DR biotype at 8 and 13 weeks after transplanting. Significant variation among DS and DR populations occurred in 37 and 33 of 56 evaluations, respectively. When variation existed within a biotype, populations exhibited broad ranges of response for the various growth parameters. With the exception of total inflorescence dry weight, DS and DR biotypes generally exhibited similar ranges of variability.

AN ANALYSIS OF DRY MATTER PRODUCTION OF DOUGLAS-FIR SEEDLINGS IN RELATION TO TEMPERATURE AND LIGHT INTENSITY

1967 ◽  
Vol 45 (11) ◽  
pp. 2063-2072 ◽  
Author(s):  
Holger Brix
Keyword(s):  
Light Intensity ◽  
Leaf Area ◽  
Dry Matter ◽  
Douglas Fir ◽  
Dry Matter Production ◽  
Dry Matter Distribution ◽  
Pronounced Increase ◽  
Light Intensities ◽  
Matter Production ◽  
Net Assimilation

Seedlings of Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) were grown in growth chambers under all combinations of three temperatures (13, 18, and 24 °C) and three light intensities (450, 1000, and 1800 ft-c). Dry matter production of leaves, stem, and roots was determined at 65 and 100 days after germination. The leaf area produced per unit of leaf dry weight and the dry matter distribution to the plant organs was measured. Net assimilation rates between the ages of 65 and 100 days were calculated. Rates of photosynthesis per unit of leaf were determined at different light intensities and temperatures, and rates of respiration of plant top and of roots were found for different temperatures.Increasing light intensity affected dry matter production in two opposing ways: (i) it increased the rate of photosynthesis per unit leaf area, and (ii) it decreased the leaf area added per unit of dry matter produced. A pronounced increase in growth with increase in temperature from 13 to 18 °C was a result of a temperature influence on production of leaf area rather than the effect of photosynthesis per unit of leaf. Net assimilation rates decreased with increase in temperature at all light intensities.

Biology of Fire Ephemerals of the Sandplains of the Kwongan of South-Western Australia

1985 ◽  
Vol 12 (6) ◽  
pp. 641 ◽  
Author(s):  
JS Pate ◽  
NE Casson ◽  
J Rullo ◽  
J Kuo
Keyword(s):  
Life Cycle ◽  
Reproductive Biology ◽  
Seedling Growth ◽  
Western Australia ◽  
Growth Rates ◽  
Dry Matter ◽  
Dry Weight ◽  
Growing Season ◽  
Adaptive Significance ◽  
Sexually Dimorphic

The growth, longevity, mineral relationships and reproductive biology of 18 species of fire ephemerals were examined in sclerophyllous shrubland, located mainly within the Jurien : Badgingarra region of the Northern Sandplains of the kwongan of SW. Australia. Ten of the species were monocarpic, completing their life cycle within the 6-8 month winter growing season after a summer or autumn fire. The remaining species were polycarpic, commencing reproduction in their second season and surviving and reproducing for a further two to eight seasons (depending on species). Detailed study was made of growth and dry matter allocation in the dioecious, sexually dimorphic, polycarpic species Tersonia brevipes (Gyrostemonaceae). Monocarpic species tended to produce smaller seeds, and exhibited greater seed output per unit biomass and higher harvest indices for dry matter and minerals than polycarpic species. Certain monocarpic species showed great plasticity in final dry weight, e.g. a 2700-fold difference between largest and smallest individuals in a sample of 250 plants of Stipa elegantissima (Poaceae), and a 180-fold range in a similarly sized sample of Macarthuria apetala (Aizoaceae). The fire ephemerals studied generally exhibited faster seedling growth rates, greater concentrations of P and N (but not of Ca, Mg and K) in seedling dry matter, but usually lesser concentrations of P and N (but not of Ca, Mg and K) in seed dry matter than in cohabiting obligate seeder or sprouter species with potential life spans exceeding 15 years. The above-mentioned features of fire ephemerals are suggested to be of special adaptive significance within the context of exploitation of transiently non-limiting habitat resources immediately following fire.

scholarly journals Growth and Development of Basil Transplants (Ocimum basilicum L.)under Biostimulants Application

2015 ◽  
Vol 15 (4) ◽  
pp. 415 ◽  
Author(s):  
Svjetlana Zeljković ◽  
Nada Parađiković ◽  
Uroš Šušak ◽  
Monika Tkalec
Keyword(s):  
Plant Height ◽  
Open Field ◽  
Root Development ◽  
Root Length ◽  
Growth And Development ◽  
Untreated Control ◽  
Dry Weight ◽  
Ocimum Basilicum ◽  
Plant Adaptation ◽  
Number Of Leaves

In this study, the influence of biostimulants Radifarm® on basil transplants (Ocimum basilicum L.) growth and development was examined.Seedlings transplanted into the PVC containers φ9 cm,the plants were tre­ated with the biostimulant concentration of 0.30% or untreated(control). During the experiment recorded the morphological indicators of growth and development of seedlings(plant height, number of leaves), and finally made measuring root length and fresh and dry weight of roots and above-groundparts.The aim of this study was to determine whether, to what extent and in what manner applied biostimulator impact on improved growth and root development of seedlings of basil, and thus improve the adaptation of the young seedlings in abiotical stress of transplanting into the open field. All the traits were affected by treatment with biostimulants a certain duration of the experiment.Research indicates that the use of biostimulants in the production of basil enhances the growth and development of roots and above-ground parts which is a prerequisite for faster plant adaptation on stress during transplanting.

Morphological acclimation to light intensity in Douglas-fir seedlings

1977 ◽  
Vol 55 (15) ◽  
pp. 2033-2042 ◽  
Author(s):  
Allan P. Drew ◽  
William K. Ferrell
Keyword(s):  
Light Intensity ◽  
Root Growth ◽  
Dry Weight ◽  
Frost Damage ◽  
Douglas Fir ◽  
Stem Length ◽  
Low Light ◽  
Spring Frost ◽  
Terminal Bud ◽  
Leaf Surface Area

Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings were grown outdoors under 9, 44, and 100% light intensity and were sampled periodically over their first growing season for stem, leaf, and root dry weights, and the data were analyzed allometrically. In addition, seedlings were assessed for number of needles per stem length, ratio leaf surface area: leaf dry weight, and maximum seedling dry weight. The experiment was repeated during a 2nd, warmer, year.Maximum growth occurred under partial shade and moderate temperatures. In the 1st year, seedlings allocated progressively more dry matter to shoot than to root growth as light intensity decreased. In the 2nd year, root growth was favored at the expense of shoot growth. In both years, shoot structural alterations were such as to favor enhanced photosynthesis under low light. Acclimative changes are explained in terms of an interaction between light, temperature, and seedling size.A second experiment showed that seedlings grown under low light set a terminal bud sooner in the fall and broke bud sooner the next spring than seedlings preconditioned to high light. They also suffered more spring frost damage and showed greater incidence of lammas growth in the 2nd year. No effect of 1st-year preconditioning on timing of budbreak was evident in the 3rd year.

Ecological studies of hypogeous fungi. II. Sporocarp phenology in a western Oregon Douglas Fir stand

1976 ◽  
Vol 54 (10) ◽  
pp. 1152-1162 ◽  
Author(s):  
Robert Fogel
Keyword(s):  
Soil Moisture ◽  
Moisture Content ◽  
Soil Moisture Content ◽  
Dry Weight ◽  
Douglas Fir ◽  
Total Weight ◽  
Ecological Studies ◽  
Hypogeous Fungi ◽  
Moisture Effects ◽  
Major Species

Sporocarp phenology of hypogeous or subterranean fruiting fleshy fungi was studied between March 1972 and March 1975 in a 40- to 65-year-old Douglas fir stand in western Oregon. Estimates of yearly productivity ranged from 11052 to 16753 sporocarps ha−1 and 2.3 to 5.4 kg dry weight ha−1. The productivity curve was bimodal as a result of temperature and moisture effects, with peaks in May–June and October. Eleven hypogeous ascomycete species and 13 hypogeous basidiomycete species were collected during the study. Major species that each accounted for 5% or more of the total weight were Tuber murinum, Hymenogaster parksii, Hysterangium crassum, H. separabile, and Truncocolumella citrina var. citrina. Sporocarp moisture content as determined for several species presumably varied with sporocarp age and soil moisture content and ranged from 17.4 to 88.6%. Hypogeous sporocarps had substantially higher macronutrient contents of N, P, and K plus the micronutrients Fe and Al than did epigeous sporocarps of Fomes pinicola. Sporocarp numbers increased exponentially with distance from nearest live Douglas fir stem to a peak at 160 to 200 cm, beyond which numbers dropped sharply. The optimum sporocarp zone was slightly less than the average midpoint between tree stems (205 cm).

scholarly journals A descriptive model o Scots pine (Pinus silvestris) L. seedling's growth during the first growing season

2015 ◽  
Vol 45 (1–2) ◽  
pp. 143-158
Author(s):  
Teresa Gowin ◽  
Leokadiusz Ubysz
Keyword(s):  
Scots Pine ◽  
Dry Matter ◽  
Growth Curves ◽  
Dry Weight ◽  
Growing Season ◽  
Logistic Growth ◽  
Descriptive Model ◽  
Relative Growth ◽  
Pine Seedlings ◽  
Net Assimilation

Scots pine seedlings were grown in pots from seed under outside conditions. Plant material was harvested ten times in fortnight periods, throughout the growing season. At each harvest, each plant was divided into particular organs and their dimensions as well as fresh and dry weight were determined. Seasonal course of growth of particular organs as well as changes in specific leaf area and distribution of dry matter between shoot and root were investigated. Net assimilation rate (NAR) and relative growth rate (RGR) were calculated from the fitted logistic growth curves.

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