Estimation of seed viability constants (KE, CW) for lentil (Lens culinaris)

Orthodox seed longevity systematically increases with reduction in temperature and moisture content, as described by the Ellis and Roberts viability equations. These equations have species-specific parameters which quantify the inherent longevity of seeds of a particular species and their sensitivity to change in moisture content. This research investigated the effect of moisture content on lentil (Lens culinaris) seed longevity during experimental storage. Seeds of an elite breeding line were stored under hermetic conditions at six different moisture contents (7.6, 8.1, 8.8, 10.1, 11.5, 12.6%) at 60°C. Ability to germinate was determined at scheduled intervals, and longevity (σ) was estimated for each treatment. The values of the constants KE (8.0008) and CW (3.746) were estimated using linear regression, by plotting log σ against log moisture content, combined with the universal temperature constants (CH = 0.0329, CQ = 0.000478). The application of these moisture constants (KE and CW) was tested by comparing the predicted viability loss of two lentil accessions with their observed longevity under hermetic storage at 12.0% moisture content and 45°C. The validity of these constants for predicting lentil seed longevity was proven, with an R2 = 0.912 (P < 0.001).