Growth In Terms Of Mass Research Articles

The relationship between leaf area growth and biomass accumulation in Arabidopsis thaliana.

Leaf area growth determines the light interception capacity of a crop and is often used as a surrogate for plant growth in high-throughput phenotyping systems. The relationship between leaf area growth and growth in terms of mass will depend on how carbon is partitioned among new leaf area, leaf mass, root mass, reproduction, and respiration. A model of leaf area growth in terms of photosynthetic rate and carbon partitioning to different plant organs was developed and tested with Arabidopsis thaliana L. Heynh. ecotype Columbia (Col-0) and a mutant line, gigantea-2 (gi-2), which develops very large rosettes. Data obtained from growth analysis and gas exchange measurements was used to train a genetic programming algorithm to parameterize and test the above model. The relationship between leaf area and plant biomass was found to be non-linear and variable depending on carbon partitioning. The model output was sensitive to the rate of photosynthesis but more sensitive to the amount of carbon partitioned to growing thicker leaves. The large rosette size of gi-2 relative to that of Col-0 resulted from relatively small differences in partitioning to new leaf area vs. leaf thickness.

Construction of Tree Biomass Tables in Turkey for the Estimating of Biomass Potential for Energy

According to economists and other observers of the energy scene, there is an impending shortage in the civilized world of petroleum and gas. Exhaustion of these nonrenewable fuels prompts consideration of alternative energy sources. One alternative source is forest biomass, which is defined as the quantity constituted by living organisms in the forest ecosystem in terms of mass. The aboveground portions of trees and shrubs transform solar energy in the form of vegetational substances. Because the forest is a renewable natural resource, plantations of trees and natural stands that were previously considered unmerchantable are now being examined as a new source of renewable energy. To help overcome a possible future energy shortage, methods of correctly managing and using forest biomass resources have to be developed now. The need for knowledge of the existing amount of standing timber and its growth in terms of mass, as measured and expressed by consistent methods and standars, is a part of this broad problem. The solution can be approached by producing biomass tables for tree species.

Nicotiana tabacum Callus Studies I. Assessment of Growth and Differentiation

Summary Nicotiana pith expiants containing bundles of internal phloem attain the same plateau of growth in terms of mass and volume after 14 days as do expiants devoid of internal phloem after 21 days. The lag appears to be related to the time required for the dedifferentiation of the quiescent pith parenchyma. Tracheary element differentiation occurred in controls as well as in all treatments with only indoleacetic acid (IAA), 0.3 mgl−1 being significantly effective. Expiants treated only with kinetin (K) developed small numbers of tracheary elements at all concentrations. Sieve elements were not induced in response to media including K but without IAA or with a high level of IAA (3 mgl−1) in the absence of K. At low and intermediate levels of IAA phloic tissue differentiated at all levels of sucrose (2, 4 and 6%) with the exception of 0.03 mgl−1 IAA, 1 mgl−1 K and 2% sucrose. There was a lack of consistency in the extent of sieve element differentiation. However, when comparing individual combinations of IAA and K among various sucrose levels, more phloem was initiated at 4 than at 2 or 6%.