Rice growth and yield characteristics under elevated carbon dioxide and nitrogen management
¹Bangabandhu Sheikh Mujibur Rahman Agricultural University, Faculty of Agriculture, Department of Agronomy, BD-1706 Gazipur, Bangladesh
²Bangabandhu Sheikh Mujibur Rahman Agricultural University, Faculty of Agriculture, Department of Forestry and Environment, BD-1706 Gazipur, Bangladesh
³Bangabandhu Sheikh Mujibur Rahman Agricultural University, Faculty of Agriculture, Department of Soil Science, BD-1706 Gazipur, Bangladesh
⁴Krishi Gobeshona Foundation, Bangladesh Agricultural Research Council, BD-1215 Dhaka, Bangladesh
*Correspondence: aamamun@bsmrau.edu.bd
Abstract:
The atmospheric carbon dioxide (CO2) concentration is increasing and the on crop production needs to be investigated. A pot experiment was conducted in open top chambers (OTC) to determine the response of rice to elevated CO2 (eCO2) under varying time of nitrogen (N) application. The results revealed that photosynthesis, root and shoot dry matter production, yield components and nutrient absorption were favored at eCO2 when N applied up to flowering stage (FT) of rice. However, the N application up to FT of rice also significantly improved percent filled grain, reduce spikelet sterility and rice yield increased by 18 to 20% under eCO2. Rice plant absorbed higher amount of Zn, Ca, Mg, and Fe at eCO2 when N was applied up to FT. Amylose was higher but protein percentage was lower at eCO2. These results indicate that to maximize rice yield under eCO2, it is important to supply N up to FT of rice in order to increase grain fertility and reduce spikelet sterility.
Key words:
crop yield, gas exchange, grain fertility, plant nutrition, rice, spikelets sterility