Seed Dormancy Breaking and Germination in Bituminaria basaltica and B. bituminosa (Fabaceae)

Abstract

Most legumes are well-known for the physical dormancy of their seeds; hence, the implementation of appropriate scarification techniques is essential for introducing new legume crops within agricultural systems. This study investigated morpho-anatomical traits and dormancy-breaking requirements in two taxa of the genus Bituminaria: the widespread B. bituminosa and the point endemic B. basaltica. As the species under investigation show monospermic indehiscent legumes, pods were used in this research. We performed pod trait measurements, light microscopy observations on the seed coat anatomical structure, and germination tests after mechanical, thermal, and chemical scarification treatments for seed dormancy breaking. Moreover, germination performance at different pod maturity stages and storage times was tested. Differences in morpho-anatomical traits were found, with B. basaltica having a thicker palisade cell layer and B. bituminosa showing larger pods. All of the scarification treatments proved to be able to break physical dormancy, with mechanical and chemical scarification being the most effective methods in both species. Nevertheless, dormancy-breaking treatments performed better in B. bituminosa. Seeds at early pod maturity stages showed higher germination capacity in both species. Overall, this research provided background knowledge on seed collection time, storage strategy, and effective pre-sowing treatment, which might contribute to enhance propagation and use of Bituminaria species for multiple purposes. Under this perspective, the future characterization of additional Bituminaria genetic resources from other Mediterranean populations will have remarkable importance.

Practical Methods for Breaking Seed Dormancy in a Wild Ornamental Tulip Species Tulipa thianschanica Regel

“…Phytohormones were involved in seed germination, particularly gibberellin (GA) and abscisic acid (ABA) [27][28][29], and it was confirmed that the combination of them had antagonistic effects on seed germination [30,31]. Gibberellin, which releases the dormancy of seeds, played a key role in promoting the rupture of testa [32,33]. Aghilian reported that GA 3 significantly increased the seed germination percentage of Plantago ovate, Rudbeckia hirta and Satureja hortensis [34].…”

Pre-Germinative Treatments and Morphophysiological Traits in Enterolobium cyclocarpum and Piscidia piscipula (Fabaceae) from the Yucatan Peninsula, Mexico

“…In several species of Fabaceae have been documented the existence of PY, see [ 3 ]. Thus, the germinative responses to the application of several kinds of pre-germinative treatments e.g., [ 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 ] have been widely evaluated in these species. In this context, Robles-Díaz [ 2 ] documented a high germination percentage in Lupinus rotundiflorus (69.8% ± 2.7%) using thermal shocks with boiling water for 10 s. We found similar results because P. piscipula had the highest germination (76.0% ± 7.95%) in thermal shocks with boiling water for 10 s. In addition, Galíndez [ 22 ] reported that mechanical scarification in A. cearensis is an efficient method to increase germination percentage and germination time.…”

Interactive Effects of Epichloë Endophyte, Dormancy-Breaking Treatments and Geographic Origin on Seed Germination of Achnatherum inebrians

“…Mechanical, thermal, and chemical treatments were compared in terms of their relative effectiveness in breaking the seed dormancy of drunken horse grass seeds. Mechanical treatment was achieved by a needle pin, which was used to tear the seed coat without piercing the embryo; thermal treatment was completed by soaking in warm water (25 • C) for 30 min; chemical dormancy break was accomplished by soaking in 98% H 2 SO 4 for 30 min [35] and in exogenous GA 1 part per million (ppm) for 20 min [36]. Intact E+ and E− seeds' different sites without any treatments were used as control seeds (CK) (Table 2).…”