Welcome to Chinese Journal of Ecology! Today is Share:

Chinese Journal of Ecology ›› 2021, Vol. 40 ›› Issue (3): 615-626.doi: 10.13292/j.1000-4890.202103.007

Previous Articles     Next Articles

Effects of source-sink manipulation on the accumulation and translocation of nonstructural carbohydrates in stems and sheaths of Japonica rice under elevated CO2 concentration and different nitrogen fertilization levels.

ANG Jing-rui1,2, CAO Pei-pei1,2, YANG Kai1,2, LYU Chun-hua1,2, WANG Yi-jie1,2, SUN Wen-juan1, YU Ling-fei1, HU Zheng-hua3, HUANG Yao1*   

  1. (1State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; 2University of Chinese Academy of Sciences, Beijing 100049, China; 3School of Applied Meteorology, Nanjing University of Information Science & Technology, Nanjing 210044, China).
  • Online:2021-03-10 Published:2021-03-12

PDF (PC)

119

Abstract: We investigated the effects of source-sink manipulation on the accumulation and translocation of non-structural carbohydrates (NSC) in the stems and sheaths of a Japonica rice (Oryza sativaL.) cultivar “Nangeng 9108” under elevated CO2 concentration (\[CO2\]) and different nitrogen (N) fertilization levels. There were two CO2 concentrations-ambient \[CO2\] (a\[CO2\]) and a\[CO2\]+200 μmol·mol-1 (e\[CO2\])-in open-top chambers (OTCs), and three N application rates, low N (N1, 10 g N·m-2), medium N (N2, 20 g N·m-2), and high N (N3, 30 g N·m-2). The source-sink manipulations were carried out by leaf cutting (LC) and spikelet removal (SR). No source-sink manipulations were set as control (CK). Leaf N content and the total mass of NSC stored in stems and sheaths (TMNSC) at heading and maturity were measured. The apparent transferred mass of NSC from stems and sheaths to grains (ATMNSC) and the apparent contribution of transferred NSC to grain yield (ACNSC) were calculated. The results showed that e\[CO2\] significantly decreased leaf N content at heading stage, and significantly promoted NSC accumulation at the N2 level. Under different \[CO2\] and N levels, SR treatment increased TMNSC at maturity but decreased ATMNSC and ACNSC. LC treatment significantly decreased TMNSC and increased ATMNSC at maturity under a\[CO2\] and different N levels. There were no significant effects of LC treatment on TMNSC and ATMNSC at maturity under elevated CO2. The LC treatment did not affect grain yield and its components. We found higher ratio of spikelet number to leaf area (grain/leaf ratio), higher ATMNSC, ACNSC, grain yield and harvest index but lower TMNSC and 1000grain weight at maturity. The factors affecting ACNSC were grain/leaf ratio, and TMNSC at heading and maturity, while those affecting grain yield were grain/leaf ratio, leaf N content and TMNSC at maturity. The relationships between ACNSC and grain yield can be quantified by multiple regression models.

Key words: rice, elevated CO2 concentration, nitrogen fertilizer, leaf cutting, spikelet removal, source-sink relationship, non-structural carbohydrates.