SpeedySeed viability kit: A rapid colourimetric assay for seed viability testing

Abstract

Seed viability and vigour are vital seed quality parameters determining the crop establishment. The traditional seed quality testing methods are time-consuming and require skilled personnel. Standard germination tests can take two to three weeks, and the tetrazolium test, though faster, demands technical expertise. The SpeedySeed Viability Kit™ offers a rapid, low-cost, on-farm alternative. The study was carried out during 2024–25 at ICAR-Indian Agricultural Research Institute, New Delhi to estimate the viability of seed lots of paddy (Oryza sativa L.) and lentil [Lens culinaris (L.) Medik.] by using SpeedySeed Viability kit. It works on the principle that viable, vigorous seeds release more CO2 during respiration. This CO2 is absorbed by a bromothymol blue indicator solution in a sealed tube, producing a colour change during the incubation—green/yellow for viable seeds and blue for non-viable seeds. The viability can be assessed in 6 h in paddy and 3 h in lentil, making it the fastest seed viability assessment method. The viability estimated closely matched the total viability by the standard germination test with a prediction accuracy ranging from 89–93% in paddy and 96–99% in lentil. The viability estimated by the kit was also validated by measuring the optical density value at 450 nm, where the lot with higher viability recorded the highest OD values. The linear regression with OD and their corresponding germination had a strong correlation with an R2 value of 0.87 in paddy and 0.76 in lentil seed lots.