Water uptake by Annona diversifolia Saff. and A. purpurea Moc. & sessé ex dunal seeds (Annonaceae)

Annonaceae seeds are known by presenting dormancy mechanisms, whose reports ranging from coating impermeable to the physiological dormancy. By this way, the present study aimed to evaluate water uptake in Annona diversifolia Saff and Annona purpurea Moc & Sessé ex Dunal seeds. For this study, seeds were placed under immersion in distilled water, and used four replicates of 25 seeds of each species, which were weighed during the 480 hours that were immersed. To determine the place of purchase of water, Annona diversifolia seeds were sealed with paraffin at different locations. Based on the results, seeds from both species reached the phases I and II of water uptake, which indicates they are not hard; however, germination (Phase III) was not reached. Annona diversifolia seeds completed Phase I with, 50h and Annona purpurea with 70h from imbibitions begin, which shows that even slowly, water is acquire.

Assessment of the physiological potential of spinach seeds (Tetragonia tetragonoides (Pall.) Kuntze)

The efficiency of vigor tests in assessing the physiological potential of seeds depends on their standardization for different species. In this context, the research aimed to study specific methodologies to evaluate the vigor of spinach seeds (Tetragonia tetragonoides). For this purpose, five lots of spinach seed cv. New Zealand were submitted to germination, first count of germination, seedling emergence in the field, accelerated aging (with and without use of saturated solution of NaCl at 41and 45 ºC for 24,48 and 72 hours), controlled deterioration (18,21 and 24% seed water content adjustments for 24 hours at 45 ºC) and electrical conductivity tests with variations inwater volume (25, 50 and 75 mL), seed quantity (25 and 50) and soaking period (1, 2, 4, 8,12, 16 and 24 hours) at 25 ºC. The first count test allowed obtaining preliminary information about seed vigor, and other tests in general showed similarity with seedling emergence in the field. Thus, it was concluded that traditional accelerated aging test 24 h /41 ºC and accelerated aging test with saturated salt solution for 24 h at 41 ºC and 45 ºC, and controlled deterioration test with 21% seed water content / 24 h / 45 ºC were all efficient for evaluating the physiological potential of spinach seeds.

Seasonal variation in the fate of seeds under contrasting logging regimes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Maturity, Pulp Removal and Storage Effects on the Germination of Livistona rotundifolia Seeds

The Livistona rotundifolia species is native to Oceania, and has a high potential for landscaping use and as a pot plant. This work aimed to study the effects of the maturation stage, pulp removal and storage on the germination of L. rotundifolia seeds. The experimental design was entirely randomized in a factorial arrangement 5x2x2 (five storage periods: 15, 30, 45, 60 and 75 days; two maturation stages: green and ripe; and the presence or absence of the pulp - exocarp and mesocarp) with four replications of 25 seeds each. After sorting out the fruits by the maturity stage and removing the pulp out of half of the fruits from each plot, the seeds were placed in closed bottles, which were sealed and stored in a cold chamber at 10 degrees C. The seeds were removed from the cold chamber and left to germinate in plastic boxes (gerbox type) with sphagnum. The boxes were kept at 25-35 degrees C and photoperiod of 12 hours. The germination rate was determined when seed germination was steady. The highest germination rate was found when green fruits had their pulp removed. The germination rate gradually decreased with the increase of the storage period regardless the maturation stage and the presence or absence of the pulp.

Effects of the Temperature and Maturation Stages on the Germination of Roystonea regia Seeds

Roystonea regia (Kunth) O.F. Cook is largely used as ornamental. The propagation is done almost exclusively by seeds; however, there is a great variation in the germination process influenced by many factors. The objective of this work was to study the effects of the temperature and maturation stages on the germination of R. regia seeds. The experimental design was entirely randomized in a factorial arrangement 6x3 (six temperatures: constant at 20, 25, 30 and 35 degrees C and alternated at 20-30 and 25-35 degrees C, with a photoperiod of 12 hours; and three fruit maturation stages: brown, yellow and black), with four replications of 25 disseminules (seed with stucked endocarp) each. The disseminules had their mesocarp and exocarp were removed and shade dried. Their moisture content was determined, and then they were placed in plastic boxes (gerbox type) containing vermiculite. The disseminules, with the germinative intumescence, were daily noted until germination was steady. The germination rate and the germination speed index were calculated, and the data were submitted to the variance analysis. The means were compared by the Tukey test. It was concluded that the highest germination rate (99.7%) and germination speed were obtained by seeds from mature (black) fruits at the temperature of 35 degrees C.

Germination of Roystonea borinquena OF Cook (Arecaceae) Seeds

This work aimed to study the effect of the temperature on the seed germination and to describe the morphology and germination process of disseminules (seeds with stucked endocarp) of R. borinquena species. The fruits were harvested and had their pulp (exocarp and mesocarp) removed and the disseminules were shade dried. The experimental design was entirely randomized and six treatments were performed (temperature conditions: constant at 25, 30 and 35 degrees C; alternated at 25-35 and 20-30 degrees C; and room temperature) with four replications with 25 disseminules per plot, placed in plastic boxes (gerbox) containing vermiculite. The germination rate and germination speed index were calculated, and the data were submitted to the variance analysis, and the means compared by the Tukey test. For the morphological studies, the external and internal sides of the disseminules, the embryo and the representative germination stages were sketched. The samples were fixed in FAA (formalin - acetic acid - ethyl alcohol). It was concluded that the highest germination rate and faster germination were at the constant temperature of 35 degrees C and alternated of 25-35 degrees C. The seeds are albuminous, with a hard endosperm that takes almost the entire interior of the disseminules; the embryo is lateral, peripheral and poorly differentiated; the germination is adjacent.

Germination of Phoenix roebelenii Seeds

The Phoenix roebelenii O'Brien is one of the most used plants in the Brazilian landscape. The work aimed to study the effect of different fruit harvesting locations, associated with seven temperature conditions, on the germination of P. roebelenii seeds. The fruits were collected from two different locations: Ilha Solteira, western Sao Paulo State and Jaboticabal in the middle East of the same State. The disseminules (seeds with stucked endocarp) were placed in plastic boxes (gerbox), and the experimental design was entirely randomized in a factorial scheme of 7x2 (seven temperatures conditions: room temperature, constant at 20, 25, 30 and 35 degrees C and alternated at 20-30 and 25-35 degrees C; and two fruit harvesting locations: Ilha Solteira and Jaboticabal, with four replications with 25 seeds each. The disseminules that emitted the germinative intumescence were daily noted until the germinative process got steady, in about 90 days. The germination rate (G%), the germination speed index (GSI), and the means were extracted and compared by the Tukey test. The highest values of germination rate were obtained at 30, 25-35 degrees C and room temperatures. The seeds showed a higher GSI at room temperature. The fruit harvesting locations influenced the germination.

Community structure of mites (Arachnida: Acari) in six rubber tree clones

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Seedling Development and Evaluation of Genetic Stability of Cryopreserved Dendrobium Hybrid Mature Seeds

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Absence of detection of xanthomonas axonopodis pv. malvacearum in cotton seeds used in the Northeast Region of Mato Grosso do Sul in a three-based crop season study

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Performance of different rubber tree clones against South American leaf blight (Microcyclus ulei)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Characterization of natural rubber membranes using scaling laws analysis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Segmentation of Scanning Electron Microscopy Images From Natural Rubber Samples With Gold Nanoparticles Using Starlet Wavelets

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Biocompatibility studies of natural rubber latex from different tree clones and collection methods

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)