Amelioration of Zn with appropriate doses, methods and time of application under low land rice

Optimizing Zn application for lowland rice productivity

Abstract

A field experiment was conducted at university's experimental farm, Gayeshpur, West Bengal during kharif
(2018) to evaluate the right dose, method and time of application of Zn in low land rice (IET-4786). Experiment
was undertaken with twelve treatments containing different doses of Zn application through soil and foliar at
different growth stages of rice. The treatments are, viz T1 =No Zn, T2= Soil application of Zn @2.5 kg ha-1
through ZnSO4.7H2O at the time of transplanting, T3= Soil application of Zn @5.0 kg ha-1 through ZnSO4.7H2O
at the time of transplanting, T4= Soil application of Zn @10.0 kg ha-1 through ZnSO4.7H2O at the time of
transplanting, T5= Two foliar sprays of Zn as ZnSO4.7H2O @0.5% (One spray at maximum tillering stage and
one at pre-flowering stage), T6 = Two foliar sprays of Zn as Zn-EDTA @0.5% (One spray at maximum tillering
stage and one at pre-flowering stage), T7= T2 + Zn spray as ZnSO4.7H2O @0.5% at the maximum tillering stage,
T8 = T3 + Zn spray as ZnSO4.7H2O @0.5% at the maximum tillering stage, T9 = T4+ Zn spray as ZnSO4.7H2O
@0.5% at the maximum tillering stage, T10 = T2 + Zn spray as Zn-EDTA @0.5% at the maximum tillering stage,
T11= T3+ Zn spray as Zn-EDTA @0.5% at the maximum tillering stage and T12= T4+ Zn spray as Zn-EDTA @0.5%
at the maximum tillering stage. The statistical design of the field experiment was laid out in Randomized
Complete Block Design (RCBD). The results of the study revealed that soil application of Zn @ 5 kg ha-1 before
transplanting of rice along with foliar application of ZnSO4.7H2O @ 0.5% at max. tillering stage was found
highly suitable for sustaining the rice production and it might be recommended to the farmers not only for
sustainable production but also for getting the quality produce. Results also showed that a very small amount
of applied Zn (<1%) is utilized by rice and its utilization is high when it is applied at lower level. Zn translocation
factor from root to shoot and shoot to grain, agronomic efficiency (AE) and apparent recovery efficiency (ARE)
were also higher at lower level of Zn applications compared to the higher levels.