Early genetic evaluation of loblolly pine

1981 ◽  
Vol 11 (2) ◽  
pp. 352-356 ◽  
Author(s):  
Michael S. Waxler ◽  
J. P. van Buijtenen
Keyword(s):  
Loblolly Pine ◽  
Growth Parameters ◽  
High Stress ◽  
Field Performance ◽  
Moisture Stress ◽  
Average Volume ◽  
Fast Growing ◽  
Stage Of Development ◽  
Shoot Weight ◽  
Slow Growing

Seedlings of five known fast-growing, open-pollinated loblolly pine (Pinustaeda L.) families and five known slow-growing families were grown from seed to 24 weeks of age in a greenhouse. Each family was subjected to four moisture regimes ranging from high stress levels to little or no stress. Various seedling growth parameters were measured and evaluated to determine their value as predictors of field performance of the same families tested over a range of site conditions. Results showed that the shoot weights and shoot/root ratios of known fast-growing families were significantly greater than those of known slow-growing families at the seedling stage of development. The average shoot/root ratio per family of seedlings grown under unstressed and mildly stressed conditions showed significant positive correlations (r = 0.74 and r = 0.61 respectively) with the average volume superiority of the same families field-tested over a range of sites. (Volume superiority = (volume of family/average volume of plantation) × 100.) The average shoot weight per family of seedlings grown under mild and moderate moisture-stress conditons were also significantly correlated (r = 0.65 and r = 0.66 respectively) with average volume superiority. Shoot/root ratio of seedlings grown under the unstressed water regime was the best overall predictor of later field performance.

scholarly journals Genotypic traits and tradeoffs of fast growth in silver birch, a pioneer tree

Oecologia ◽  
2021 ◽  
Author(s):  
Juha Mikola ◽  
Katariina Koikkalainen ◽  
Mira Rasehorn ◽  
Tarja Silfver ◽  
Ulla Paaso ◽  
...  
Keyword(s):  
Resource Competition ◽  
Leaf Growth ◽  
N Uptake ◽  
Insect Herbivory ◽  
Fast Growth ◽  
Grass Cover ◽  
Soil N ◽  
Fast Growing ◽  
Slow Growing ◽  
Leaf N

AbstractFast-growing and slow-growing plant species are suggested to show integrated economics spectrums and the tradeoffs of fast growth are predicted to emerge as susceptibility to herbivory and resource competition. We tested if these predictions also hold for fast-growing and slow-growing genotypes within a silver birch, Betula pendula population. We exposed cloned saplings of 17 genotypes with slow, medium or fast height growth to reduced insect herbivory, using an insecticide, and to increasing resource competition, using naturally varying field plot grass cover. We measured shoot and root growth, ectomycorrhizal (EM) fungal production using ergosterol analysis and soil N transfer to leaves using 15N-labelled pulse of NH4+. We found that fast-growing genotypes grew on average 78% faster, produced 56% and 16% more leaf mass and ergosterol, and showed 78% higher leaf N uptake than slow-growing genotypes. The insecticide decreased leaf damage by 83% and increased shoot growth, leaf growth and leaf N uptake by 38%, 52% and 76%, without differences between the responses of fast-growing and slow-growing genotypes, whereas root mass decreased with increasing grass cover. Shoot and leaf growth of fast-growing genotypes decreased and EM fungal production of slow-growing genotypes increased with increasing grass cover. Our results suggest that fast growth is genotypically associated with higher allocation to EM fungi, better soil N capture and greater leaf production, and that the tradeoff of fast growth is sensitivity to competition, but not to insect herbivory. EM fungi may have a dual role: to support growth of fast-growing genotypes under low grass competition and to maintain growth of slow-growing genotypes under intensifying competition.

scholarly journals Studies on the Regulation of Algal Growth by Gibberellin

1971 ◽  
Vol 24 (4) ◽  
pp. 1115 ◽  
Author(s):  
RC Jennings
Keyword(s):  
Red Algae ◽  
Algal Growth ◽  
Red Alga ◽  
General Phenomenon ◽  
Hypnea Musciformis ◽  
Fast Growing ◽  
High Concentrations ◽  
Amo 1618 ◽  
Slow Growing

CCC and Amo.1618, at relatively high concentrations only, inhibited the growth of excised branch apices of the red alga Hypnea musciformis. Neither GA3 nor GA7 stimulated growth of the alga in the presence or absence of these compounds, and gibberellin-like material extracted from H. musciformis also failed to stimulate growth. However, both gibberellins stimulated the growth of slow-growing, but not fast-growing, branch apices of the related red alga Gracilaria verucosa. It is concluded that endogenous gibberellins may not regulate the growth of H. musciformis, but this is likely to be a peculiarity of this species and not a general phenomenon in red algae.

scholarly journals Interactive effects of ambient ozone and climate measured on growth of mature loblolly pine trees

1996 ◽  
Vol 26 (4) ◽  
pp. 670-681 ◽  
Author(s):  
S.B. McLaughlin ◽  
D.J. Downing
Keyword(s):  
Soil Moisture ◽  
Loblolly Pine ◽  
Moisture Stress ◽  
Growth Patterns ◽  
Forest Growth ◽  
Interactive Effects ◽  
Forest Trees ◽  
Short Term ◽  
Data Set ◽  
Ambient Ozone

Seasonal growth patterns of mature loblolly pine (Pinustaeda L.) trees over the interval 1988–1993 have been analyzed to evaluate the effects of ambient ozone on growth of large forest trees. Patterns of stem expansion and contraction of 34 trees were examined using serial measurements with sensitive dendrometer band systems. Study sites, located in eastern Tennessee, varied significantly in soil moisture, soil fertility, and stand density. Levels of ozone, rainfall, and temperature varied widely over the 6-year study interval. Regression analysis identified statistically significant influences of ozone on stem growth patterns, with responses differing widely among trees and across years. Ozone interacted with both soil moisture stress and high temperatures, explaining 63% of the high frequency, climatic variance in stem expansion identified by stepwise regression of the 5-year data set. Observed responses to ozone were rapid, typically occurring within 1–3 days of exposure to ozone at ≥40 ppb and were significantly amplified by low soil moisture and high air temperatures. Both short-term responses, apparently tied to ozone-induced increases in whole-tree water stress, and longer term cumulative responses were identified. These data indicate that relatively low levels of ambient ozone can significantly reduce growth of mature forest trees and that interactions between ambient ozone and climate are likely to be important modifiers of future forest growth and function. Additional studies of mechanisms of short-term response and interspecies comparisons are clearly needed.

SENSITIVITY AND ADAPTATION OF SELECTED RHIZOBIA AND AGROBACTERIA TO PARAQUAT

1985 ◽  
Vol 65 (3) ◽  
pp. 555-562 ◽  
Author(s):  
E. B. ROSLYCKY
Keyword(s):  
Key Words ◽  
Genetic Effect ◽  
Agrobacterium Radiobacter ◽  
Plant Weight ◽  
Fast Growing ◽  
Plant Symbiont ◽  
Paraquat Resistance ◽  
Rhizobium Lupini ◽  
The Relationship ◽  
Slow Growing

Sensitivity to paraquat as function of growth varied considerably among 15 rhizobia from seven cross-inoculation groups and 13 agrobacteria from five different species. No relationship was evident between the sensitivity and the "fast-growing" or the "slow-growing" characteristics among the rhizobia. The agrobacteria were uniformly less sensitive. Maximum stabilized paraquat resistance induced by the adptations ranged from 200 μg paraquat∙mL−1 in Rhizobium lupini 112, to 20 000 μg paraquat∙mL−1 in Agrobacterium radiobacter R-590 and A. tumefaciens A6-K1. No relationship was found between the sensitivity and the adaptability. Identical lytic patterns with six bacteriophages confirmed the relationship between the adapted and parent cultures suggesting no genetic effect of paraquat on susceptibility to lysis. The bacteria-plant symbiont interaction, including nodulation, plant weight, vigor and color, was unaffected by the adaptations to paraquat resistance. Similarly, the adaptations exerted no effect on tumorigenicity of A. tumefaciens A6-K1. Key words: Rhizobia, agrobacteria, adaptation, herbicides, paraquat, N2-fixation

scholarly journals The Spatial Heterogeneity of the Black Scorpionfish, Scorpaena porcus (Scorpaenidae): Differences in Length, Dietary and Age Compositions

2021 ◽  
Vol 11 (24) ◽  
pp. 11919
Author(s):  
Josipa Ferri ◽  
Sanja Matić-Skoko
Keyword(s):  
High Selectivity ◽  
Adriatic Sea ◽  
Multivariate Analyses ◽  
Growth Parameters ◽  
Island Area ◽  
Intraspecific Variations ◽  
Geographical Scale ◽  
Diet Analyses ◽  
Slow Growing ◽  
Scorpaena Porcus

The present study assessed spatial variations in several biological characteristics of Scorpaena porcus Linnaeus, 1758 and estimated length structure, dietary composition and growth parameters for the species. Sampling was carried out in two areas, about 200 km apart, in the coastal Adriatic Sea, which is the northernmost region of the Mediterranean. A total of 388 specimens of S. porcus were caught, 233 from the Split area and 155 from the Pag Island area, and a higher proportion of individuals in the ≤15 cm length classes were found in the Split area. The results of the age, growth and diet analyses demonstrated that the black scorpionfish is a slow-growing and long-lived species that feeds on a wide variety of plant and animal taxa and shows a high selectivity for crustacean decapods. Detailed comparisons and multivariate analyses showed significant fine-scale spatial structuring of the investigated species, as observed length, dietary and age compositions were heterogeneous among the two areas. Fish from the Pag Island area ingested a greater diversity of the prey types, fed to a greater extent on fishes, reached the highest total length and showed a higher growth rate. Such intraspecific variations could reflect adaptations to different environmental conditions and support the geographical scale at which local black scorpionfish populations should be managed.

scholarly journals Current state of Donetsk dendroflora

2016 ◽  
Vol 5 (2) ◽  
pp. 20-24
Author(s):  
Alexandr Zakharovych Glukhov ◽  
Lyudmila Valerievna Kharkhota ◽  
Georgy Alexandrovych Pasternak ◽  
Elena Nikolaevna Likhatskaya
Keyword(s):  
Age Structure ◽  
Steppe Zone ◽  
Age Group ◽  
Fast Growing ◽  
Industrial City ◽  
Current State ◽  
Study Results ◽  
Slow Growing ◽  
Trees And Shrubs ◽  
Fast Growing Species

We present the study results of modern dendroflora of Donetsk (a large industrial city of the south steppe zone). We have determined the species composition, analyzed the age structure of plantations, estimated the life condition of trees and shrubs. Plantations compose 76 species and 32 forms, types, sorts of trees, including 11 species and 9 sorts of the coniferous, as well as 79 species and 35 forms, sorts of shrubs, including 7 species and 19 sorts of the coniferous. Trees and shrubs belong to 78 genera, which are included into 38 families. The most represented family among the deciduous is Rosaceae Juss. - 46 species and 13 sorts, among the coniferous - Pinaceae Lindl. (9 species and 6 sorts), Cupressaceae Rich. ex Bartl. (7 species and 22 sorts). Tree species dominating in plantations are Populus bolleana Lauche (14,6% of the total number of trees), dominating shrubs are the sorts of Rosa hybrida (44,0% of the total number of shrubs). In the plantations studied we have indicated 33 species of trees and shrubs of the aboriginal fraction of local flora. Analysis of the age structure of plantations revealed that the majority of trees compose the age group of 20-29 years, the majority of shrubs - up to 10 years. Fast-growing species prevail in plantations (73% of the total number). Viability of the most part of trees of fast-growing and slow-growing species is estimated by 4 points, viability of moderate-growing species - by 6 points. The number of trees being in unsatisfactory condition (0 or 1-3 points) prevails among fast-growing species.

scholarly journals The creation and trial of a serious game to support teaching and learning of professional psychology competencies in postgraduate programs

2019 ◽  
Author(s):  
Gillian McGregor ◽  
Emma Bartle
Keyword(s):  
Game Design ◽  
Design Theory ◽  
Teaching And Learning ◽  
High Stress ◽  
Psychology Students ◽  
Professional Psychology ◽  
The Body ◽  
Serious Game ◽  
Safe Delivery ◽  
Stage Of Development

The education of healthcare professionals is critical for the safe delivery of services to patients (Ricciardi & de Paolis, 2014). Postgraduate psychology students undertaking a professional degree encounter a steep learning curve when transitioning from theoretical knowledge to professional practice. This beginning student stage of development is fraught with anxiety and high-stress levels, and has implications for both student and client wellbeing (Skovholt & Ronnestad, 2003). Successful navigation of this phase is critical to psychology graduate competence and employability, with potentially lasting consequences for psychologists’ perceptions of self-efficacy and career trajectory (De Stefano et al., 2007; Skovholt & Ronnestad, 2003). Serious games in health provide the potential for safe practice opportunities in an engaging and entertaining manner (Hawn, 2009; Knight et al., 2010). The author developed a serious game with the intention of providing postgraduate professional psychology students with increased and more convenient opportunity to practice psychological competencies. This paper synthesises game design theory into a prototype for educators to provide innovative solutions in a health context. It contributes to the body of research determining the efficacy of games in educational contexts and advances knowledge in the use of simulation pedagogies.

scholarly journals Effects of Combined Application of Cow Manure And Inorganic Nitrogen Fertilizer on Growth, Yield and Nitrogen Uptake of Black Rice

Akta Agrosia ◽  
2018 ◽  
Vol 21 (2) ◽  
pp. 55-60
Author(s):  
Marwanto Marwanto ◽  
Nasiroh Nasiroh ◽  
Bambang G. Mucitro ◽  
Merakati Handajaningsih
Keyword(s):  
Growth Parameters ◽  
N Uptake ◽  
Fertilizer Application ◽  
N Fertilizer ◽  
Root Weight ◽  
Cow Manure ◽  
Black Rice ◽  
Inorganic N ◽  
Yield Attributes ◽  
Shoot Weight

The beneficial effects of manure on soil properties, growth, and crop productivity have promoted its use for replacing the application of N fertilizer. However, it is not well understood to what extent N fertilizer was able to be substituted by cow manure. Accordingly, this pot experiment aimed to compare the effect of inorganic N fertilizer application alone with that of the combined use of inorganic N fertilizer with cow manure based on the same amount of total N on growth parameters, yield attributes, and nitrogen (N) uptake of black rice. The experiment was conducted under a screen house condition in Agriculture Faculty, Bengkulu University located at 15 meters altitude above sea level during the summer season of 2015. There were six treatments viz. T1 = 100% N from urea + 0% N from cow manure (0.52 g N + 0.00 g cow manure) pot-1, T2 = 80% N from urea  + 20% N from cow manure  (0.42 g N + 9.55 g cow manure) pot-1, T3 = 60% N from urea + 40% N from cow manure (0.31 g N  + 19.10 g cow manure) pot-1, T4 = 40% N from urea + 60% N from cow manure (0.21 g N + 28.65 g cow manure) pot-1, T5 = 20% N from urea + 80% N from cow manure (0.10 g N+ 38.20 g cow manure) pot-1, and T6 = 0% N from urea + 100% N from cow manure (0.00 g N  + 47.75 g cow manure) pot-1. The amount of inorganic N fertilizer in the form of urea and cow manure applied was calculated based on the recommended rate of 115.00 kg ha-1 for N fertilizer and 10.50 ton ha-1 for cow manure. These treatments were arranged in a Completely Randomized Design and repeated three times. The results showed that the treatments significantly (P ?0.005) affected growth parameters as measured by plant height, the number of leaves, fresh shoot weight, fresh root weight, dry shoot weight, dry root weight, yield attributes as determined by the total number of tillers, the total number productive tillers, grain yield per pot, and N uptake. The highest values for all these variables were obtained in the treatment receiving recommended rate of urea only (100% N from urea + 0% N from cow manure as equivalence) and the lowest in the treatment receiving a100% N from cow manure (0% N from urea + 100% N from cow manure). However, combined treatments of cow manure and inorganic N fertilizer such as 80% N from urea  + 20% N from cow manure, 60% N from urea + 40% N from cow manure 40% N from urea + 60% N from cow manure showed a parity statistically with the treatment receiving 100% N from urea only in maintaining the values for all these variables. Overall, the combined use of inorganic N fertilizer (urea) and cow manure as an equivalence promoted growth and yield of black rice by improving N uptake. Keywords: integrated nutrient management, soil chemical property, Nitrogen uptake, combined fertilizer application, black rice

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