TY - JOUR
T1 - Morphological and physiological traits of roots and their relationships with shoot growth in "super" rice
AU - Zhang, Hao
AU - Xue, Yaguang
AU - Wang, Zhiqin
AU - Yang, Jianchnag
AU - ZHANG, Jianhua
N1 - Funding Information:
We are grateful for grants from the national Basic Research Program (973 Program, 2009CB118603), the National Natural Science Foundation of China (30771274, 30871480), the Doctoral Foundation of Ministry of Education, China (200811170002), Research Grant Council of Hong Kong (HKBU 2465/05 M), Hong Kong University Grants Committee (AOE/B-07/99), and Hong Kong Baptist University Matching Research Fund.
PY - 2009/7/10
Y1 - 2009/7/10
N2 - Success in "super" rice breeding has been considered a great progress in rice production in China. This study aimed to test the hypothesis that an improved root system may contribute to better shoot growth and consequently to higher grain yield in "super" rice. Two "super" rice varieties Liangyoupeijiu (an indica hybrid) and Huaidao 9 (a japonica inbred) and two elite check varieties Yangdao 6 (an indica inbred) and Yangfujiang 8 (a japonica inbred) were field-grown at Yangzhou, China in 2006 and 2007. Root and shoot dry weight (DW) was significantly greater in "super" rice varieties than in check ones throughout the growth season in both years, so was the root length density. Root oxidation activity (ROA) and root zeatin (Z) zeatin riboside (ZR) content, in per plant basis, were significantly greater in "super" rice than check varieties before and at heading time. However, both ROA and root Z + ZR content, either in per plant basis or per unit root DW basis, were significantly lower in 'super' rice than in check varieties at the mid- and late grain filling stages. Grain yield of the two 'super' rice varieties, on average, was 10.2 t ha-1 in 2006 and 11.4 t ha-1 in 2007, and was 13% and 21% higher than that of check varieties, respectively. The high grain yield was mainly due to a larger sink size (total number of spikelets) as a result of a larger panicle. The percentage of filled grains of the two "super" rice varieties, on average, was 72.9% in 2006 and 79.0% in 2007, and was 19.4% and 12.9%, respectively, lower than that of the check varieties. The mean ROA and root Z + ZR content during the grain filling period significantly correlated with the percentage of filled grains. Collectively, the data suggest that an improved root and shoot growth, as showing a larger root and shoot biomass and greater root length density during the whole growing season and higher ROA and root Z + ZR content per plant at early and mid-growth stages, contributes to the large sink size and high grain yield in the "super" rice varieties. The data also suggest the yield of "super" rice varieties can be further increased by an increase in filled grains through enhancing root activity during grain filling.
AB - Success in "super" rice breeding has been considered a great progress in rice production in China. This study aimed to test the hypothesis that an improved root system may contribute to better shoot growth and consequently to higher grain yield in "super" rice. Two "super" rice varieties Liangyoupeijiu (an indica hybrid) and Huaidao 9 (a japonica inbred) and two elite check varieties Yangdao 6 (an indica inbred) and Yangfujiang 8 (a japonica inbred) were field-grown at Yangzhou, China in 2006 and 2007. Root and shoot dry weight (DW) was significantly greater in "super" rice varieties than in check ones throughout the growth season in both years, so was the root length density. Root oxidation activity (ROA) and root zeatin (Z) zeatin riboside (ZR) content, in per plant basis, were significantly greater in "super" rice than check varieties before and at heading time. However, both ROA and root Z + ZR content, either in per plant basis or per unit root DW basis, were significantly lower in 'super' rice than in check varieties at the mid- and late grain filling stages. Grain yield of the two 'super' rice varieties, on average, was 10.2 t ha-1 in 2006 and 11.4 t ha-1 in 2007, and was 13% and 21% higher than that of check varieties, respectively. The high grain yield was mainly due to a larger sink size (total number of spikelets) as a result of a larger panicle. The percentage of filled grains of the two "super" rice varieties, on average, was 72.9% in 2006 and 79.0% in 2007, and was 19.4% and 12.9%, respectively, lower than that of the check varieties. The mean ROA and root Z + ZR content during the grain filling period significantly correlated with the percentage of filled grains. Collectively, the data suggest that an improved root and shoot growth, as showing a larger root and shoot biomass and greater root length density during the whole growing season and higher ROA and root Z + ZR content per plant at early and mid-growth stages, contributes to the large sink size and high grain yield in the "super" rice varieties. The data also suggest the yield of "super" rice varieties can be further increased by an increase in filled grains through enhancing root activity during grain filling.
KW - "Super" rice (Oryza sativa L.)
KW - Grain filling
KW - Root dry weight
KW - Root oxidation activity
KW - Sink size
KW - Zeatin + zeatin riboside
UR - http://www.scopus.com/inward/record.url?scp=67349089265&partnerID=8YFLogxK
U2 - 10.1016/j.fcr.2009.04.004
DO - 10.1016/j.fcr.2009.04.004
M3 - Journal article
AN - SCOPUS:67349089265
SN - 0378-4290
VL - 113
SP - 31
EP - 40
JO - Field Crops Research
JF - Field Crops Research
IS - 1
ER -