Bean Report
DEVELOPMENT OF THE INTERNODE LENGTH OF VIGNA RADIATA WHEN GROWN UNDER DIFFERENT LIGHT INTENSITIES
ABSTRACT
Throughout their growth plants exhibit varying ways to adapt and change depending on their circumstances, with changes in the amount of available light being a major factor in plant growth. The aim of the study was to determine whether there are significant differences in the growth patterns of Vigna radiata when grown under varying light intensities. Plants were grown in two different light intensities, normal light and no light, for a period of 10 days to determine two different phototrophic effects.
The results demonstrated that there was a significant difference between the internode lengths of V. radiata grown under the different light intensities, with the plants grown in normal light having shorter internode lengths than the plants grown in no light.
It is clear that the rate of development of structural characteristics is significantly greater for plants grown in normal light intensities then those grown in no light as their features are underdeveloped.
INTRODUCTION
Unlike most animals once a plant has established its root system in a specific location in cannot move significantly. Plants require sunlight in order for photosynthesis to occur and thus allow the plant to produce its own glucose. In order to maximise their ability to photosynthesis plants can alter their growth, either positively or negatively in response to external stimuli. These responses often cause a directional movement or elongation in growth and are called tropisms (Raven et al., 2005). If this growth exhibits a positive response to light then it is called a phototropism and will result in the plant growing or bending toward the light source (Campbell et al., 2006).
Photomorphogenic responses are light induced growth patterns which occur when a plant seedling is grown in sufficient light conditions. These responses initiate the uncurling of seedling stems and increase
ABSTRACT
Throughout their growth plants exhibit varying ways to adapt and change depending on their circumstances, with changes in the amount of available light being a major factor in plant growth. The aim of the study was to determine whether there are significant differences in the growth patterns of Vigna radiata when grown under varying light intensities. Plants were grown in two different light intensities, normal light and no light, for a period of 10 days to determine two different phototrophic effects.
The results demonstrated that there was a significant difference between the internode lengths of V. radiata grown under the different light intensities, with the plants grown in normal light having shorter internode lengths than the plants grown in no light.
It is clear that the rate of development of structural characteristics is significantly greater for plants grown in normal light intensities then those grown in no light as their features are underdeveloped.
INTRODUCTION
Unlike most animals once a plant has established its root system in a specific location in cannot move significantly. Plants require sunlight in order for photosynthesis to occur and thus allow the plant to produce its own glucose. In order to maximise their ability to photosynthesis plants can alter their growth, either positively or negatively in response to external stimuli. These responses often cause a directional movement or elongation in growth and are called tropisms (Raven et al., 2005). If this growth exhibits a positive response to light then it is called a phototropism and will result in the plant growing or bending toward the light source (Campbell et al., 2006).
Photomorphogenic responses are light induced growth patterns which occur when a plant seedling is grown in sufficient light conditions. These responses initiate the uncurling of seedling stems and increase
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