Plant Growth Dynamics: Analysis of Basic Spatial and Temporal Growth Patterns on the Background of Photosynthetic Energy Gain and Interactions with the Environment

Author(s):  
Achim Walter
1993 ◽  
Vol 89 (1) ◽  
pp. 33-39 ◽  
Author(s):  
Jeff S. Kuehny ◽  
Mary C. Halbrooks

Weed Science ◽  
1971 ◽  
Vol 19 (1) ◽  
pp. 93-97 ◽  
Author(s):  
F. W. Roeth ◽  
T. L. Lavy

The uptake of 2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine (atrazine) was studied in sudangrass [Sorghum sudanense(Piper) Stapf, var. Piper], grain sorghum [Sorghum bicolor(L.) Moench], and corn (Zea maysL.) to find whether differences in atrazine uptake exist among these species. The uptake of atrazine followed closely the growth patterns of corn, sorghum, and sudangrass during the first 5 weeks of growth. Concentration of14C from ring-labeled14C-atrazine in the soil reached a peak in corn, sorghum, and sudangrass plants after 2 weeks of growth and then declined. The14C concentrations were two to three times greater in sorghum and sudangrass than in corn throughout the 5-week period. Atrazine uptake per gram of plant growth by these crops was directly proportional to the concentration of atrazine in the soil and the proportionality factors were in the order: sudangrass < sorghum ≫ corn. Total uptake and the total growth were in order: corn ≫ sorghum = sudangrass. In a study where relative humidity was a variable, the amount of atrazine absorbed per ml of water was inversely related to total water usage.


2005 ◽  
Vol 32 (5) ◽  
pp. 421 ◽  
Author(s):  
Liezel M. Gouws ◽  
C. Barry Osmond ◽  
Ulrich Schurr ◽  
Achim Walter

Distinct diel rhythms of leaf and cladode expansion growth were obtained in crassulacean acid metabolism (CAM) plants under water-limited conditions, with maxima at mid-day during phase III of CO2 assimilation. This pattern coincided with the availability of CO2 for photosynthesis and growth during the decarboxylation of malic acid, with maximum cell turgor due to the nocturnally accumulated malic acid, and with the period of low cytoplasmic pH associated with malic acid movement from vacuole to cytosol. Maximum growth rates were generally only 20% of those in C3 plants and were reached at a different time of the day compared with C3 plants. The results suggest that malic acid, as a source of carbohydrates, and a determinant of turgor and cytoplasmic pH, plays a major role in the control of diel growth dynamics in CAM plants under desert conditions. The observed plasticity in phasing of growth rhythms under situations of differing water availability suggests that a complex network of factors controls the diel growth patterns in CAM plants and needs to be investigated further.


1993 ◽  
Vol 89 (1) ◽  
pp. 33-39 ◽  
Author(s):  
Jeff S. Kuehny ◽  
Mary C. Halbrooks

2007 ◽  
Vol 69 (1) ◽  
pp. 144-157 ◽  
Author(s):  
R. Mata-González ◽  
R.G. Hunter ◽  
C.L. Coldren ◽  
T. McLendon ◽  
M.W. Paschke

2008 ◽  
Vol 4 (3) ◽  
pp. 282-285 ◽  
Author(s):  
A Chinsamy ◽  
L Codorniú ◽  
L Chiappe

Life-history parameters of pterosaurs such as growth and ontogenetic development represent an enigma. This aspect of pterosaur biology has remained perplexing because few pterosaur taxa are represented by complete ontogenetic series. Of these, Pterodaustro is unique in that besides being represented by hundreds of individuals with wing spans ranging from 0.3 to 2.5 m, it includes an embryo within an egg. Here we present a comprehensive osteohistological assessment of multiple skeletal elements of a range of ontogenetic sizes of Pterodaustro , and we provide unparalleled insight into its growth dynamics. We show that, upon hatching, Pterodaustro juveniles grew rapidly for approximately 2 years until they reached approximately 53% of their mature body size, whereupon they attained sexual maturity. Thereafter, growth continued for at least another 3–4 years at comparatively slower rates until larger adult body sizes were attained. Our analysis further provides definitive evidence that Pterodaustro had a determinate growth strategy.


2017 ◽  
Vol 10 (6) ◽  
pp. 571-576 ◽  
Author(s):  
Marielle Ernst ◽  
Anika Buchholz ◽  
Romain Bourcier ◽  
Hubert Desal ◽  
Pierre-Yves Le Floch ◽  
...  

BackgroundUnderstanding aneurysm growth is critical for the appropriate follow-up of patients after coil embolization and the need for retreatment. The purpose of the study was to stratify the growth dynamics of aneurysm recurrences after coiling by volumetric analysis and to determine predictive factors for aneurysm recurrences.MethodsSource images of follow-up three-dimensional time of flight MR angiography (ToF-MRA) scans were compared with the first post-interventional ToF-MRA scan and analyzed for residual flow after co-registration using ANALYZE-software. In the event of incomplete occlusion, the residual volume was segmented and calculated. Growth dynamic was determined for each aneurysm after embolization.ResultsWe analyzed 326 patients with 345 aneurysms from two centers. Each case had at least two ToF-MRA examinations after endovascular therapy. The mean observation interval was 59 months. Volumetric analysis of 1139 follow-up MRAs revealed that 218/345 aneurysms (63.2%) showed complete occlusion on initial follow-up imaging, and of these 95.0% remained stable. A steady increase in intra-aneurysmal flow was observed in 83/345 (24.1%). Less frequent observations were a steep increase (21/345; 6.1%) and a decrease (27/345; 7.8%). Independent predictors of increasing residual flow were greatest aneurysm diameter, total coil length, and incomplete occlusion.ConclusionsVolumetric analysis of registered three-dimensional ToF-MRA follow-up datasets allows the detection of different growth patterns with high precision, avoids the low inter-rater reliability, and represents a promising approach for future studies that include analysis of more complex predictors of residual flow. In cases of aneurysm recurrence after coiling, the major pattern seems to be a steady increase in intra-aneurysmal flow over several months.


1967 ◽  
Vol 45 (5) ◽  
pp. 681-689
Author(s):  
R. G. Lockard ◽  
E. J. A. Asomaning

The early growth of six cacao varieties important in the breeding program of the Cocoa Research Institute was investigated in sand cultures supplied with optimum and deficient levels of plant nutrients. The varieties tested were the Amazon selections Nanay (Ny) and Parinari (Pa), West African Amelonado (A), and their hybrids, NyA, PaA, and NyPa. Varieties Ny, NyA, and NyPa had similar growth patterns and were the fastest growing; varieties PaA and Pa were similar and the next best; and A was the slowest growing. In the control solutions variety Pa was larger than variety A, but in all deficient nutrient treatments except the calcium-deficient one, the two varieties grew to equal size.Nutrient levels in the leaves did not vary greatly between varieties, and apparently were not correlated with plant growth. The larger, more vigorous varieties had a higher percentage of small lateral absorbing roots than did the less vigorous varieties.The Amazon varieties Ny and Pa grew significantly less in the potassium-deficient nutrient solution than did the Amelonado variety A when compared with their controls. In addition, the symptoms of potassium deficiency exhibited by the Amazon varieties were more severe than those of the Amelonado variety.


Author(s):  
Daiga Oboļeviča ◽  
Antons Ruža

Also, each treatment of the field results in a certain stress for the plants. The natural physiological processes within a plant are hindered influencing the growth of a plant. The objectives of the paper were to determine influence of retardant, herbicide and nitrogen on growth dynamics and the development o f vegetation stages in winter wheat. The field experiments were carried out during 1998 to 1999 in Research and Training Farm "Pēterlauki" on sod calcareous medium loam, pH k c l — 7.0, humus content 20 to 25 g kg 1 in soil. The research was carried out in the fields o f intensive type of winter wheat 'Otto' with the following treatments: control; control + herbicide; control + retardant; Ngo + 70 +40 + retardants. Herbicide Dialen (2,01 ha~’) and retardant Cikocel (1,5 l haT1 ) was applied during the final stage o f tillage, when testing parted nitrogen fertiliser, the first part (N go) was used after vegetation period was resumed. The second part (N70) was applied at the beginning of stalking stage (Zadoks Growth Stage 30). The third part (N40) - during shooting into ears. The grovAng dynamics was registered by aucsinographs (designed by I.Gronskis, M.Āboliņš). This equipment allows to observe and to register the intensity o f plant growth length within twenty-four hours. Registration tapes were changed every twenty-four hours. The analysis of the results showed that the most intensive plant growth happened in the morning (9:00 - 12:00 a.m.) and in the afternoon (3:00 - 6:00 p.m.). A decrease in the growing intensity was observed during night and midday. The data show how that the growth of winter wheat was seriously hindered even 2 weeks after the treatment with agro-chemicals. Winter wheat growing in length stops in the middle of flowering stage.


Author(s):  
Jacqueline Jacot ◽  
James R. Kiniry ◽  
Amber S. Williams ◽  
Addison Coronel ◽  
Jianzhong Su ◽  
...  

Near-surface remote sensing has been used to document seasonal growth patterns (i.e. phenology) for plant communities in diverse habitats. Phenology from this source may only apply to the area within the images. Meanwhile ecosystem models can accommodate variable weather and landscape differences to plant growth, but accuracy is improved by adding ground-truthed inputs. The objective of this study was to use PhenoCam data, image analysis, and Beer’s law with established extinction coefficients to compare leaf area index (LAI) development in the ALMANAC model for diverse plant types and environments. Results indicate that PhenoCam time series imagery can be used to improve leaf area development in ALMANAC by adjusting parameter values to better match LAI derived values in new diverse environments. Soybeans, mesquite, and maize produced the most successful match between the model simulations and PhenoCam data out of the eight species simulated. This study represents, to our knowledge, the first independent evaluation of the ALMANAC process-based plant growth model with imagery in agroecosystems available from the PhenoCam network. The results show how PhenoCam data can make a valuable contribution to validate process-based models, making these models much more realistic and allows for expansion of PhenoCam influence.


Sign in / Sign up

Export Citation Format

Share Document