Rice Productivity, Zn Biofortification, and Nutrient-Use Efficiency as Influenced by Zn Fertilization Under Conventional Transplanted Rice and the System of Rice Intensification
Anil K. Choudhary, Pankaj Sood, Shakuntla Rahi, D.S. Yadav, Omika Thakur, K. R. Siranta, Anchal Dass, Y V SINGH, Adarsh Kumar, Adarsh Kumar, S Vijayakumar, Ingudam Bhupenchandra, Vikas Dua, Shivadhar, R.S. Bana, Vijay Pooniya, Seema Sepat, Sushil Kumar, Mahendra Vikram Singh Rajawat, G. A. Rajanna, M. N. Harish, T. Varatharajan, Anil Kumar, Anil Kumar, Vishal Tyagi
Abstract
The northwestern Himalayas (NWH) in India have low rice productivity (∼2 t ha −1 ) and quality due to poor crop and nutrient management in predominantly Zn-deficient soils. Hence, a field experimentation in the NWH compared the conventionally transplanted rice (CTR) and the system of rice intensification ( SRI) under three nutrient management practices (NMPs), viz ., 1) farmers’ fertilization practice, FYM @ 5 t ha −1 + N:P 2 O 5 :K 2 O @ 50:40:20 kg ha −1 (FFP); 2) recommended dose of fertilization, FYM @ 10 t ha −1 + N:P 2 O 5 :K 2 O @ 90:40:40 kg ha −1 (RDF); and 3) RDF + Zn fertilization using ZnSO 4 @ 25 kg ha −1 (RDF + Zn). The results revealed that SRI practice harnessed a significantly higher rice yield under different NMPs (6.59–8.69 t ha −1 ) with ∼1.3–1.4- and ∼3.3–4.3-fold enhancements over the CTR and average rice productivity in NWH, respectively. SRI had the greatest improvement in panicle number hill −1 by ∼2.4 folds over the CTR. RDF + Zn had a significantly higher grain (10.7; 7.9%) and straw yield (28.9; 19.7%) over FFP and RDF, respectively, with significant augmentation of Zn biofortification in grains (11.8%) and Zn uptake (23.9%) over the RDF. SRI also enhanced the Zn concentrations in rice grains and straws by ∼4.0 and 2.7% over CTR with respective increases of 36.9 and 25.9% in Zn uptake. The nutrient harvest index and partial factor productivity of applied nutrients (NPK) had a higher magnitude under SRI and RDF + Zn over their respective counterparts, i.e., CTR and RDF. In addition, SRI had higher AE-Zn, CRE-Zn, and PE-Zn to the tune of 119.6, 63.4, and 34%, respectively, over the CTR. Overall, SRI coupled with RDF + Zn in hybrid rice assumes greater significance in enhancing the rice productivity with better Zn-biofortified grains besides higher nutrient use efficiencies to combat widespread malnutrition and acute Zn deficiencies in humans and livestock in the northwestern Himalayas.