3.3 Zn concentrations in rice tissues
Genotypes varied significantly in concentrations
of Zn in rice tissues and Zn accumulation in the rice
grain. In all treatments, Jiaxing27 had significantly
higher Zn concentration (Table 4, Fig. 1) and Zn
accumulation (Fig. 2) than Nipponbare. Significant
variations of water managements were also observed
in Zn concentration and accumulation in rice plant
(Table 4, Fig. 1) and rice grain (Fig. 2). Compared
with CF, AWD significantly increased Zn concentrations
in both shoot and root by 5.88% and 7.12%,
respectively. And Zn concentration and accumulation
in both brown rice and polished rice increased by
2.0%–3.9% and 13.8%–15.5%, respectively.
Zn fertilization had significant impacts on Zn
concentration and accumulation in the rice plants
(Table 4) and grains (Figs. 1 and 2). Compared to no
Zn application, Zn fertilization significantly increased
Zn concentrations in both shoot and root by 11.4%–
14.5% and 37.4%–52.2%, respectively. Zn concentration
in brown rice increased from 29.3 mg/kg in the
control treatment to 32.4 mg/kg by ZnSO4 fertilization
and to 31.5 mg/kg by Zn-EDTA fertilization, and
increased overall by 10.6% and 7.5%, respectively.
And the Zn concentration in polished rice increased
from 23.3 mg/kg in the control treatment to 24.7 mg/kg
by ZnSO4 application and to 24.8 mg/kg by Zn-
EDTA application, and increased overall by 6.3%
and 6.6%, respectively. Zn accumulations in both
brown rice and polished rice showed increases of
27.8%–38.3% and 29.7%–43.7%, respectively, depending
on different Zn sources. And these effects
were much more pronounced when Zn was supplied
with ZnSO4.