Calcium Nitrate Priming Increases the Germination Rate of Eggplant Seeds

The priming may promote greater expression of the physiological potential of the seeds and contribute to the germination process under adverse environmental conditions. The objective of this study was to evaluate the physiological potential of eggplant seeds primed with different chemical agents and exposed to adverse temperatures. Seeds were subjected to priming with five chemical agents [unprimed (control); water (hydropriming); calcium nitrate (0.2%); amino acid L-phenylalanine (0.05%); L-phenylalanine (0.05%) + calcium nitrate (0.2%)] and at temperatures of 15, 25, 35 and 41 ºC, considering a completely randomized design in a factorial arrangement (5 × 4) with four replicates. The first count of radicle emission and germination, final radicle emission, seed germination, radicle emission rate index, mean radicle emission time, and seedling dry mass were measured. Germination process of eggplant seeds was completely inhibited at 41 ºC, and the optimal temperature for seed germination is 25 ºC. Calcium nitrate priming potentiates the seed germination process, resulting in higher radicle emission rate index and higher germination rate. Low temperature (15 ºC) has greater interference in the germination rate of eggplant seeds when compared to high temperature (35 ºC).