Effect of Shading on Rice Growth Characteristics Under Different Temperature Conditions

Effect of Shading on Rice Growth Characteristics Under Different Temperature Conditions

Environmental factors play an important role in crop growth and development. In recent years, climate change has become a challenge that limits environmental factors. Light is an important environmental factor for photosynthesis in rice. In addition, temperature is one of the most important factors for rice production; thus, a 1°C increase in temperature because of climate change can affect rice growth and development. Therefore, we investigated the effect of shading on the growth characteristics of rice under different temperature conditions from the vegetative stage to the flowering stage. Plants were grown at three different temperatures: 26°C/16°C for 21°C, 29°C/19°C for 24°C, and 22°C/32°C for 27°C in a phytotron. A 55% shade treatment was applied after 10 days of transplanting until the flowering stage. Plant height was not affected by the shading treatment. In the maximum tiller number response to shading, a lower tiller number and growth speed of tiller was found in the 27°C condition. Among leaf characteristics, shading increased the flag leaf area, length, width, and effective leaf area; however, it decreased the leaf number on the main stem, especially at 27°C. In terms of stem characteristics, shading affected culm wall thickness in both varieties. Finally, regarding the panicle characteristics, lower panicle numbers, spikelet numbers per panicle, primary numbers, and secondary numbers per panicle were found under the shading treatment. Most of the desirable characteristics were affected by the shading treatment at 27°C. Overall, these results indicated that shading had a greater effect on rice plant growth at high temperature.