DISCONTINUOUS HYDRATION ON THE GERMINATION OF Mimosa caesalpiniifolia AND Pityrocarpa moniliformis SEEDS UNDER WATER STRESS

Abstract

<jats:p>ABSTRACT The use of discontinuous hydration cycles can act in improving seed germination and seedling initial growth under water stress. In this context, the objective of this study was to evaluate the effect of discontinuous hydration on the germination of Mimosa caesalpiniifolia and Pityrocarpa moniliformis seeds under water stress. For this, seeds of these species were subjected to 0 (without hydration), 2 and 4 hydration cycles (18 h) and dehydration (12 and 18 h, respectively), with subsequent germination under water stress simulated for osmotic potentials of 0.0 (distilled water), -0.2, -0.4, -0.6 and -0.8 MPa. Seedlings were evaluated using tests of germination, germination speed index, mean germination time and seedling length. Discontinuous hydration in M. caesalpiniifolia and P. moniliformis seeds hampers germination and vigor of seedlings under water stress up to -0.6 MPa. However, the use of two cycles in P. moniliformis favors germination under more severe water stress (-0.8 MPa).</jats:p>

Seed characterization and germination morpho-physiology of Simira gardneriana (Rubiaceae)

“…The low seed moisture associated with small seed size at dispersal indicates that S. gardneriana is a pioneer species and has orthodox seeds. These are dispersed with low moisture content in the Caatinga ecosystem (Oliveira et al, 2014;Correia et al, 2019;Nicolau et al, 2020). This class of seeds can be stored for a longer period of time under controlled conditions of temperature and humidity (Marcos-Filho, 2015).…”

“…Luckow & R.W. Jobson (Fabaceae) (Nicolau et al, 2020), 24 h for Cenostigma pyramidale (Tul.) Gagnon & G.P.…”

“…The native Caatinga forest species reach Phase III in different periods, 36 h for M. caesalpiniifolia and 38 h for P. moniliformis (Nicolau et al, 2020), 54 h for C. pyramidale (Dantas et al, 2008a) and 152 h for S. brasiliensis (Dantas et al, 2008b). These differences are directly associated with seed characteristics for each species, regardless of botanical family.…”

Ultrasound for Overcoming Dormancy of Fabaceae Seeds From Brazilian Dry Seasonal Forest

“…Probably, the composition of P. moliniforms can be moved to other conditions by Ultrasound disassociate provocation by membrane degradation occurred in this research, according to Felix et al (2020 a, b) and Felix et al (2021). Nicolau et al (2020) and Felix et al (2021) agree that P. moliniforms seeds appear to be resistant to many processes, but often they are only impacts or gauge input. This is a factor that may have been the cause of the problematic use of ultrasound for the treatment of dormancy in this species.…”

“…These seeds show overcoming dormancy. The species is used to This species can be used in the recovery of degraded areas, as well as in the supply of wood for firewood and in the production of agglomerate, forage leaves in animal feed, and flowers in beekeeping for honey production, according to Felix et al (2020 a, b), Felix et al (2021), andNicolau et al (2020).…”