Temperature Effects on Radish Root Development
Temperature Effects on Radish (Raphanus sativus) Root Development
Abstract
Several studies have been conducted to establish how temperature, seed germination, and root growth are related. Because temperature plays a main role in many growth processes, we decided to focus on how it affected root growth. Radish (Raphanus sativus) seeds were chosen due to their ability to produce a distinct bulbous tuber, and their relatively short growing time. Three test groups were placed under different temperature conditions. There was one “control” group, one “hot” group, and one “cold” group. All test groups were placed in metal trays and set on a cycle of 12 hours of light exposure and12 hours of dark exposure. Each group was monitored and given the appropriate amount of water to maintain moist soil. The radishes were removed from their soil and root lengths were measured. We then ran a two-tailed t-test to determine if there was a significant difference between groups. We found that there was no difference between hot and control groups, but that a significant difference did exist between the cold and hot/control groups. This is most likely because the radishes used are grown in the summer and are not accustomed to the colder temperatures.
Introduction
The relationship between temperature, seed germination, and root growth has been established through studies dating back to the 1800’s. Almost all studies have been conducted with a constant temperature for 24 hours a day (Reddick 1917). A 12 hour cycle was chosen to reinforce the strong diurnal rhythms that are shown in most dicots (Yazdanbakhsh and Fisahn 2011). The majority of plant root growth occurs during dark periods and exposure to different temperatures during this period has been shown to produce the greatest response (Yazdanbakhsh and Fisahn 2011).
Percentage of water within a seed greatly affects seed germination (Waggoner 1971). As percentage of water increases seed germination time also increases.
Abstract
Several studies have been conducted to establish how temperature, seed germination, and root growth are related. Because temperature plays a main role in many growth processes, we decided to focus on how it affected root growth. Radish (Raphanus sativus) seeds were chosen due to their ability to produce a distinct bulbous tuber, and their relatively short growing time. Three test groups were placed under different temperature conditions. There was one “control” group, one “hot” group, and one “cold” group. All test groups were placed in metal trays and set on a cycle of 12 hours of light exposure and12 hours of dark exposure. Each group was monitored and given the appropriate amount of water to maintain moist soil. The radishes were removed from their soil and root lengths were measured. We then ran a two-tailed t-test to determine if there was a significant difference between groups. We found that there was no difference between hot and control groups, but that a significant difference did exist between the cold and hot/control groups. This is most likely because the radishes used are grown in the summer and are not accustomed to the colder temperatures.
Introduction
The relationship between temperature, seed germination, and root growth has been established through studies dating back to the 1800’s. Almost all studies have been conducted with a constant temperature for 24 hours a day (Reddick 1917). A 12 hour cycle was chosen to reinforce the strong diurnal rhythms that are shown in most dicots (Yazdanbakhsh and Fisahn 2011). The majority of plant root growth occurs during dark periods and exposure to different temperatures during this period has been shown to produce the greatest response (Yazdanbakhsh and Fisahn 2011).
Percentage of water within a seed greatly affects seed germination (Waggoner 1971). As percentage of water increases seed germination time also increases.
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