Abstract Structural studies in seeds with physical dormancy (PY) are important to better understand its causes and release when subjected treatments for breaking. The aims of this study were (1) characterize the PY break; (2) examine role different seed structures water uptake; (3) identify gap Senna multijuga seeds. Imbibition patterns dormant non-dormant (subjected breaking treatments) morphological changes during germination evaluated. To gap, micropyle lens blocked separately, absorption...

Under natural conditions, large seeds with physical dormancy (PY) may become water permeable earlier than small ones. However, the mechanism for this difference has not been elucidated. Thus, our aim was to evaluate traits associated PY in of Senna multijuga (Fabaceae) and propose a dormancy-break seeds. Two seedlots were collected each separated into Seed dry mass, content, thickness palisade layer hilar distal regions ratio between (P) lens fissure seed mass (M) evaluated. Further,...

Abstract Cassia is a diverse legume genus widespread in the (sub-)tropical zone of world. Several studies have been done on this genus; however, significant changes occurred at taxonomic level over years. This has led to inaccurate information about seed dormancy since many species are no longer included genus. Thus, our work aims investigate and update kind that occurs seeds also look into two notorious group ( C. fistula javanica ) compare myxospermous vs. non-myxospermous regarding...

The aims of this study were to evaluate the influence embryo adjacent tissues in water uptake and treatments release dormancy macaw palm seeds. To assess absorption with or without opercular tegument (OT), seeds immersed for 0, 12, 24, 48, 72, 96, 120, 168, 240, 360, 480 720 hours content isolated embryos was determined. In OT, gibberellic acid (GA3) solutions at concentrations 50, 100, 500, 1000 2000 mg.L-1 applied on OT region using a culture medium. another experiment, removed left intact...

Different structures have been shown to act as a water gap in seeds with physical dormancy (PY), and Fabaceae they are commonly located the hilar region. However, function of pleurogram, structure extra-hilar region that is common legume seeds, remains unknown. Our aims were review literature for occurrence pleurogram Fabaceae, determine if can open, compare functional morpho-anatomy gaps 11 Senna species.

Cycling of sensitivity to physical dormancy (PY) break has been documented in herbaceous species. However, it not reported tree seeds, nor the effect seed size on PY-breaking evaluated any Thus, aims this study were investigate how PY is broken seeds tropical legume Senna multijuga, if exhibit cycling and affects induction into sensitivity. Dormancy germination intact scarified from two collections S. multijuga. The effects temperature, moisture dormancy-breaking assessed, seasonal changes...

Abstract Swartzia langsdorffii seeds have recalcitrant characteristics. Nonetheless, dispersal begins in the month with lowest precipitation studied region, which could lead to seed death by desiccation. Therefore, objectives of this study were: (1) characterize physiological behaviour S. related their desiccation sensitivity/tolerance; and (2) assess morphophysiological characteristics that enable remain viable after dispersal. Fruits were subjected biometric evaluation anatomical...

The macaw palm is a tropical with significant potential for biofuel production; however, seed dormancy major factor limiting its agro-industrial use. present study evaluated the effects of phytoregulators in overcoming dormancy. We immersion solutions gibberellic acid (GA3) (0, 2000 and 5000 mg L-1) during two exposure times (24 48 hours), associated removal or maintenance opercular tegument, as well associations between GA3 (2000 L-1), indole-3-butyric (IBA) benzylaminopurine (BAP) repeated...

Abstract The integrative effects of zinc (Zn; 0 mg L −1 , 75 150 and 200 ) temperature (25 °C, 30 35 °C) on seed germination the threatened Brazilian species Dimorphandra wilsonii were evaluated. Zinc only observed at °C °C. By stimulating respiration rates, rising temperatures accentuate hydrogen peroxide (H 2 O formation in germinating seeds presence Zn. Seed Zn tolerance was related to activation enzymatic antioxidants, ascorbate peroxidase (APX) activity had a central role H scavenging...

Abstract Diaspore structure has been hypothesised to play a role in seed viability and/or germination of recalcitrant seeds, especially for Swartzia langsdorffii . Thus, this work aims (i) investigate the situ contribution pericarp and aril on germination, (ii) identify morphoanatomical traits S. diaspores that allow its desiccation‐sensitive seeds remain viable. The survival was investigated by placing whole fruit, (arillate seed) bare (without aril) soil forest understorey, assessing...

A structure called the pleurogram makes up a large part of seed coat some species in subfamilies Caesalpinioideae and Mimosoideae Fabaceae, but little is known about its function. It has been hypothesized that this acts as hygroscopic valve during maturation drying seeds. However, new hypothesis recently emerged proposes distinct function for pleurogram.Here, we provide an overview pleurogram, which diverse complex. This can be dislodged, thereby creating pathway water entry into...

Abstract Seed longevity is dependent on seed traits and storage conditions. This study evaluated the physical dormancy (PY)-break of two species Dimorphandra endemic to Brazilian biodiversity hotspots. Longevity was tested in situ, by burying seeds their natural habitats (12 months), ex situ , a cold chamber (5°C; 24 months). Seeds were taken at regular intervals assess germinability 30°C h photoperiod) using intact scarified seeds. Intact (freshly collected, after 12 months storage)...