The spectral composition of the light transmitted through forest canopy, dry and moist litter leaves, intact was measured in a tropical rain Mexico. Germination photoblastic seeds some pioneer trees shrubs studied over quality gradient, field germination experiments on surface floor beneath layer. There is shift to longer wavelengths inside that even greater litter. Light filtered dead leaves strongly inhibits as demonstrated with laboratory experiments. role filter might be important...

There is considerable confusion in the literature concerning impermeability of seeds with 'hard' seed coats, because ability to take up (imbibe) water has not been tested most them. Seeds Opuntia tomentosa were reported recently have a water-impermeable coat sensu lato (i.e. physical dormancy), combination physiological dormancy. However, dormancy known occur Cactaceae. Therefore, aim this study was determine if O. are water-permeable or water-impermeable, i.e. they The micromorphology and...

To determine whether seeds of the weedy shrub Wigandia urens, from Valley Mexico, undergo natural priming when buried in soil, comparative experiments were performed with seeds: (1) harvested directly plants; (2) three habitat conditions; and (3) laboratory primed polyethylene glycol. Seeds sown a growth chamber shade house. Final germination percentages, emergence, emergence rates, survival initial determined. Burial enhanced parameters evaluated Effects treatments on not significantly...

Cenchrus ciliaris is one of the most important invasive plants in northwestern México and southwestern United States, threatening conservation desert thorn scrub. Our knowledge about mechanisms that underlie its capacity for invasion limited. Here, we evaluate effect light, temperature, gibberellic acid, osmotic potential, heat shock experimental fire on caryopses germination from an invader population, exploring hypothesis fast under a wide range environmental conditions facilitates...

Abstract Ecological restoration of disturbed areas requires substantial knowledge the germination native plants and creation novel methods to increase seedling establishment in field. We studied effects soil matrix priming on Dodonaea viscosa seeds, which exhibit physical dormancy. To this end, we buried both pre‐scarified (in H 2 SO 4 , 3 min) non‐pre‐scarified seeds Parque Ecológico de la Ciudad México. After were unearthed, they post‐scarified for 0, 2, 6 10 min their percentages compared...

We studied effects of dehydration and rehydration on germination seeds six mature tropical rain forest species-Cupania glabra Swartz, Cymbopetalum baillonii Fries, Poulsenia armata (Miq.) Standl., Stemmadenia donnell-smithii (Rose) Woodson, Rheedia edulis Triana & Planch. an understory palm Chamaedorea alternans H. Wendl.-from Veracruz, México. Before the were sown, their water content was reduced by 0 (control), 30, 54 72% original content. Dehydration affects ability to rehydrate, as well...

Natural priming promotes fast and synchronic seed germination enhances the establishment of seedlings from Wigandia urens seeds. In this study, seeds species were buried in field three different sites, each site was divided into microsites (natural priming). They then exhumed air‐dried at beginning rainy season. The control W. tested for differences germination, protein patterns derived heat‐stable phospho‐protein enriched fractions, sucrose concentrations, amylase isoenzyme patterns, as...

It was evaluated the effect of two different sources local inocula from contrasting sites (mature forest, pasture) arbuscular mycorrhizae fungi (AMF) and a non-mycorrhizal control on plant growth six woody species differing in functional characteristics (slow-, intermediate- fast-growth), when introduced seasonally tropical dry forest (STDF) converted into abandoned pasture. Six plots (12 X 12m) were set as AMF inoculum source. replicates arranged Latin Square design each plot. Plant height,...

1. The heterogeneity of the light environment (in time and space) in a tropical rain forest understorey its effect on germination response heliophile tree Piper auritum was studied field laboratory. 2. In laboratory we found responses to range R: FR (red: far-red) ratios length exposure them. Blue promoted small germination. germinated even at very low levels red (0.005 μmol m −2 s −1 ). 3. were typically (0.25-0.41), with sporadic high values. conditions, seed controlled by ratio during...

In tropical dry forests, although seed germination and seedling establishment are in general limited by the seasonal availability of water, high interspecific variability, nonetheless, exists terms traits dynamics. Differences among species may be related to other plant life-history traits, such that assessing these relationships increase our understanding factors influencing establishment, which would affect regeneration pathways forest communities. this study, taking into consideration...

We assessed the effects of seed priming and soil retainers on germination early seedling performance useful species in a tropical semideciduous forest Veracruz, México. determined mass water lipid content seeds Albizia saman, Cedrela odorata, Enterolobium cyclocarpum, Swietenia macrophylla. The were exposed to hydropriming natural (seed burial inside soil) germinated at 25°C 25/35°C. produced seedlings grown shade house planted plain terrain hillside (slope 75%). Seedling growth survival...

The effect of maternal light environment on the sensitivity seeds a rain forest pioneer tree Piper auritum was studied. In relation to red:far-red (R:FR) value at maturation, spikes were classified as exposed (R:FR = 0.83-O.86), intermediate (0.57), shaded (0.40, 0.41) and deep (0.26). Differences in quality that experience during maturation cause different germination responses R:FR ratio. One most distinct results high induced partial inhibition ratios environment. Very low had comparable...

Hardwood and softwood cuttings of Buddleia cordata HBK, Dodonaea viscosa Jacq Senecio praecox D.C. were tested for their ability to form adventitious roots. Cuttings prepared in two different seasons (wet dry) treated with concentrations auxins (IBA NAA) microclimatic conditions. B. rooted during the dry wet season, whilst hardwood D. only S. season a higher rooting than cuttings. Low hormone (10 – 100 ppm) favored percentage more high concentrations. However, number, length roots number...

Restoration requires techniques similar to those used in agriculture improve germination and seedling vigor. We treated 6‐year‐old (collected 2003, S‐2003) 1‐month‐old (S‐2009) seeds of Dodonaea viscosa with hydropriming ( HP ). Seeds were made permeable hot water prior hydration for 24 or 48 hours ‐24 ‐48, respectively) followed by dehydration. The resulting seedlings exposed both treatments sown a lava field soil mixed hydrogel HG ) under the shade projected five vegetation patches....

The major components of annual seed deposition in the rain forest at Los Tuxtlas, Veracruz, México are seeds pioneer tree species Cecropia obtusifolia and those some Ficus. Bertol. forms a relatively persistent viable soil bank, whereas Ficus seldom found soil. Both genera require light for germination; however, differ their germination responses to far red (FR) under laboratory field conditions. Seeds C. did not germinate low red/far (R/FR) or pure FR, did. This suggests that do become...

The effect was studied of sunlight and far‐red (FR) light during seed development, on quality germination Sicyos deppei G. Don. Seeds exposed to FR development were lighter in colour their weight, size water content significantly lower. Less than 10% non‐scarified freshly harvested seeds germinated. Scarified, developed under had a partially negative photoblastic response; both red (R) inhibited germination. highest fastest occurred darkness, probably due the high photon flux densities...