Speakers

Biography

Dr. Sunandana Mandal is working as an Assistant Professor in the department of Chemistry at Moyna College (Affiliated to Vidyasagar University), India. She completed her Ph.D. degree from Visva-Bharati in Soil Science and Agricultural Chemistry under the guidance of Prof. Goutam Kumar Ghosh. During her Ph.D. work, she received Rajiv Gandhi National Fellowship (RGNF) funded by UGC from 2015 to 2020.

Abstract

Zn deficiency has become a major problem which causes reduction in yield and nutritional quality of the cereal grain, thus affecting human health. Zn deficiency appears to be more acute in case of rice consumers as rice is more prone to Zn deficiency amongst other cereals. Hence, biofortification of rice grain appears to be a high priority research area. Keeping in view of this, the laboratory and field experiments were carried out in lateritic soil of West Bengal, India.

100 surface soil samples were collected from five selected blocks of Birbhum district, West-Bengal, India to delineate available Zn status along with other available micro and macronutrients status. The soils were found strongly acidic to neutral in soil reaction and available Zn content varied from deficient to marginal range. For better crop quality and yield, Zn fertilizer needs to be applied.

Five soil profiles, at three different depths, were collected from those blocks to study the vertical distribution of available Zn along with macro and other micronutrients with the help of GPS and recorded the longitude and latitude of the area. Available macro, micronutrients and different Zn fractions decreased down the profile. The information obtained from vertical distribution study is helpful for both deep and shallow rooted crops.

Field experiments on biofortification of Zn in rice grain were carried out in Agricultural Research Farm during 2017 (wet season) and 2018 (dry season). The experiments were conducted in a randomized block design (RBD) with three replicates, comprising in total of twenty four plots. Treatment combinations are: T₁: No Zn i.e. control; T₂: NPK + Zn @ 5 kg Zn/ha (basal); T₃: NPK + Zn @ 5 kg Zn/ha (25 days after transplanting); T₄: NPK + Zn @ 5 kg Zn/ha (at the time of flowering); T₅: NPK + Zn @ 5 kg Zn/ha (half of ZnSO₄.7H₂O at the time of land preparation + half of ZnSO₄.7H₂O after 25 days of transplanting); T₆: NPK + Zn @ 5 kg Zn/ha (half of ZnSO₄.7H₂O at the time of land preparation + half of ZnSO₄.7H₂O at the time of flowering); T₇: NPK + Zn @ 5 kg Zn/ha (half of ZnSO₄.7H₂O after 25 days after Transplanting + half of ZnSO₄.7H₂O at the time of flowering); T₈: NPK + 0.03% Nano Zn application (spray) at the time of flowering and post-flowering.

Results obtained from field experiments revealed that plant height, chlorophyll content, 1000-grain weight increased significantly with Zn treatments over control. Zn fertilization had significant effect on grain, straw and biological yield. Highest grain yield was received for the treatment T₅. Grain and straw Zn concentration significantly increased with Zn fertilization at various growth stages of rice crop in comparison to control. Soil Zn application was found more effective in increasing yield whereas in terms of increasing grain Zn concentration, foliar Zn application was found more effective. N, P, K, Zn uptake also increased significantly with Zn fertilization over control. Significant and positive correlations were recorded between different plant parameters.