Silicon Sources and Bacterial Inoculants on Growth Parameters, Leaf Yield, Quality of Coriander (Coriandrum sativum L.) and Soil Adsorbed Silicon in Sandy Loam Soil

Aims: The objective of the present study was to investigate the effect of different silicon sources with and without microbial inoculants on growth parameters, leaf yield and quality of Coriander.

Study Design: Factorial Completely Randomized Block Design (FCRD) was used in the present study with thirty-six treatments and three replications.

Place and Duration of Study: The pot culture experiment was carried out in the Department of Soil Science and Agricultural Chemistry, Tamil Nadu Agricultural University, Coimbatore, India during January to March 2022.

Methodology: A pot culture experiment was conducted with different silicon sources namely CaSiO3, MgSiO3 and Rice Husk Ash (RHA) at three levels (0, 50 and 100 mg Si kg-1) with and without two silicate solubilizing bacteria (SSB) and a zinc solubilizing bacterium (ZSB) at 2 kg ha-1 with coriander CO (CR) 4. The influence of the treatments on growth parameters, leaf Si content, leaf yield, total soluble sugar content of leaf and soil adsorbed Si were investigated at 25 and 50 DAS.

Results: The results revealed a significant influence of Si sources with bacterial inoculants. The plant height and SPAD index values were the highest by the application of RHA­ @ 100 mg Si kg-­1 + SSB4 followed by CaSiO3 @ 100 mg Si kg-­1 + SSB4. All the sources increased the leaf Si as well as soil adsorbed Si and the effect was highly significant when Si sources were combined with SSB4 and other inoculants. Coriander leaf yield ranged from 4.32 to 8.24 g plant-1. The maximum leaf yield was recorded with the application of RHA @ 100 mg Si kg-­1 with SSB4 (8.24 g plant-1) followed by RHA @ 50 mg Si kg-­1 with SSB4 (7.67 g plant-1) and ­ CaSiO3 @ 100 mg Si kg-­1 with SSB4 (7.56 g plant-1). The effect of Si sources with bacterial inoculants on TSS content of leaf was significant with a maximum value of (38.23 mg g-1 DW) by RHA @ 100 mg Si kg-­1 + SSB4 followed by CaSiO3 @ 100 mg Si kg-­1 + SSB4 (36.10 mg g-1 DW).

Conclusion: The current study revealed that the combined application of Si sources and microbial inoculants significantly enhanced the growth attributes, leaf Si, leaf yield, leaf quality of coriander and soil adsorbed Si. The leaf yield increase over control for RHA @ 100 mg Si kg-­1 with SSB4 was 88.92 per cent followed by RHA @ 50 mg Si kg-­1 with SSB4 (76.58%) and CaSiO3 @ 100 mg Si kg-­1 with SSB4 (73.82%). The research work needs further validation at the field level.