Effect of NPK, FYM and Zn application on transformation of Zn, biological properties and nutrient availability under rice-wheat cropping system in calcareous soil
Loading...
Date
2023
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
RPCAU, Pusa
Abstract
The present study aimed to investigate the effect of NPK, FYM, and Zn application within a RWCS in calcareous soil on various aspects, including yield, nutrient uptake, chemical properties, and biological characteristics of post-harvest soil of second wheat crop in the year 2023. Additionally, the study examined different fractions of zinc in the soil and their correlations with each other, as well as with yield, nutrient uptake, and available zinc content. The research was conducted as a field experiment that commenced during the kharif season of 2021 at the Pusa Research Farm of RPCAU Samastipur, Bihar. The experimental layout followed a randomized block design comprising ten treatments replicated three times. These treatments included a range of conditions: T1 as the absolute control, T2 with RDF (Recommended Dose of Fertilizers), T3 with RDF and FYM @ 5 t ha-1, T4 with RDF and foliar spray of 0.5% ZnSO4, T5 with RDF and 5 kg Zn ha-1, T6 with RDF and Geoxol.com @ 40 kg ha-1, and T7, T8, T9, T10 similar to T2, T3, T4, T5, respectively, but with an increased RDF level of 125%. Among these treatments, T10 (125% RDF + 5 kg Zn ha-1) exhibited the highest yield of 5.21 t ha-1 and 4.64 t ha-1 with grain yield response of about 6.3 to 27.1 and 0.21 to 0.90 per cent in rice and wheat crop respectively. However, when considering nutrient uptake, T8 (125% RDF + FYM @5 t ha-1) showed the greatest total nutrient uptake, and it was statistically similar to treatments involving increased fertility levels in combination with organic supplementation and zinc sources. Remarkably, substantial nutrient availability (N, P, K, S, and Zn) was detected in treatments with enhanced fertility levels, both independently and in various combinations. Moreover, treatment T8 demonstrated noteworthy dominance in biological properties, indicating that FYM and higher fertilizer levels played a pivotal role in stimulating microbial growth. This heightened response was most pronounced in treatments involving 125% RDF, either alone or in combination, mainly due to the initial nutrient deficiency of the soil. Analyzing different zinc fractions in the post-harvest soil indicated that the water-soluble and exchangeable forms were minimal, while the residual form was predominant revealing that the majority of total zinc resided in the residual form. Interestingly, positive and significant correlations were observed among yield, nutrient uptake, and available zinc content. The order of dominance of different zinc fractions in the soil was: Residual-Zn > Organically bound-Zn > Zn bound to crystalline oxide > Zn bound to amorphous oxide > Complexed-Zn > Water soluble plus exchangeable-Zn. These findings inform agricultural practices and soil management strategies to farmers by emphasizing the benefits of balanced NPK fertilization with organic supplementation and zinc for improved crop yields. They underscore the importance of addressing micronutrient deficiencies, particularly zinc, and highlight the role of organic matter in enhancing soil health. Additionally, the study offers insights into nutrient build-up and zinc distribution, guiding more efficient soil fertility strategies. Overall, these findings promote a holistic approach to soil and nutrient management, enhancing sustainability in agriculture.