Effect of Coatings on Physical and Engineering Properties of Carrot (Daucus carota L.) Seeds in relation to the Planter Design

Abstract

The biometric properties of seeds play an important role in designing seed metering device. Physical and engineering properties of carrot seed both uncoated S-1 and coated with biogas slurry S-2 and Thirame S3 were evaluated in the laboratory. The average length and breadth of the uncoated, slurry coated and Thirame coated seed were 2.90 +/- 0.58 and 0.96 +/- 0.2 mm; 3.01 +/- 0.45 and 1.02 +/- 0.1 mm; 2.77 +/- 0.69 and 1.40 +/- 0.42 mm, respectively. Biogas slurry coating enhanced the length and breadth, mean diameter of seed with 5 % level of significance. Roundness and sphericity of uncoated, slurry coated and Thirame coated seed were 48.82 +/- 0.33 and 34.57 +/- 0.34; 30.75 +/- 0.27 % and 34.4 +/- 0.41; 44.12 +/- 0.42 % and 33.3 +/- 0.21 %, respectively. Mean diameter was maximum for Thirame coated seed S-3 (1.33 +/- 0.26mm) followed by slurry coated seed S-2 (1.23 +/- 0.18 mm), and uncoated seed S-1 (1.17 +/- 0.11 mm), respectively. Thousand seed weight, W 1,000 of S-1, S-2 and S-3 was 1.63 +/- 0.13 g, 2.15 +/- 0.6 g and 3.77 +/- 0.50 g, respectively. Percent increment in 1,000 seed weight of S-2 was 24.03 due to biogas slurry coating and the W 1,000 of S-3 was highest, which was 56.37 percent higher than the uncoated seed S-1. Angle of repose and static coefficient of friction for mild steel surface were 35.3 +/- 14.1 degrees and 0.73 +/- 0.05; 36.13 +/- 10.8 degrees and 0.74 +/- 0.03; 36.46 +/- 13.1 degrees and 0.78 +/- 0.1 for uncoated seed S-1, slurry coated seed S-2 and Thirame coated seed S-3, respectively.