[Show abstract][Hide abstract] ABSTRACT: The objective of study was to verify if desiccation and storage of the seeds affect the morphoanatomy and histochemistry of the seedlings of Campomanesia adamantium. The fruits were processed and seeds were subjected to desiccation to 30, 20, 15, 10 and 5% water contents in laboratory conditions and subsequently subjected to the following storage conditions: In the laboratory (LAB) (25 ± 2°C, 35% RH), cold and dry chamber (CC) (16 ± 2°C, 40% RH), refrigerator (REF) (8 ± 2°C, 35% RH), and freezer (FZ) (-18 ± 1°C, 42% RH) for 0 (newly processed), 30, 60, 90, 120, 150, and 180 days. The evaluation of the seedling survival rate was performed for 42 days, calculated as the survival percentages for seedling shoot and primary root. Anatomical observations and histochemical tests were performed using fixed and non-fixed samples of the median region of xylopodium in normal and abnormal seedlings. In the morphoanatomy of normal seedlings, we observed cotyledons, hypocotyl, xylopodium, and well defined primary root and in abnormal seedlings, cotyledons, hypocotyl and xylopodium (with 20 and 15% water content), and hypocotyl and primary root (with 10% water content). The desiccation and storage of seeds affected the formation of seedlings by preventing the normal development of roots and shoots. The xylopodium of normal and abnormal seedlings showed positive reaction to starch and lipophilic substances. The presence of phenolic compounds and fructans were observed in parenchyma cells of the xylopodium in abnormal seedlings and absent in normal ones. The deleterious effects of desiccation in association with storage induce the production of phenolic compounds and fructans in abnormal C. adamantium seedlings.
African journal of agricultural research 09/2015; 10(33):3216-3224. DOI:10.5897/AJAR2015.9967 · 0.26 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to evaluate the level of sensitivity to desiccation of Campomanesia xanthocarpa seeds and reduce it by using polyethylene glycol (PEG) and abscisic acid (ABA) to maintain viability. In experiment I, the seeds were desiccated to 35, 30, 25, 20, 15, 10, and 5 ± 2% moisture content by using silica gel (fast drying) and by drying them at room conditions (slow drying; 25 ± 2°C and 35% relative humidity). In experiment II, the seeds were soaked for 0, 60, and 120 h in PEG (-1.48 MPa), with ABA at different concentrations (0, 10-3 , 10-4 and 10-5 µM). Subsequently, they were desiccated to 15% moisture content by fast drying. C. xanthocarpa seeds are sensitive to desiccation; however, we showed that slow drying them at 25°C room temperature for 12.5 h to 15% moisture level, and then fast drying by using silica gel for 7 h to 20% water content maintained long-term seed viability. Sowing must be performed immediately to avoid further moisture loss. Osmotic conditioning, irrespective of whether abscisic acid was used, did not reduce the sensitivity to desiccation of C. xanthocarpa seeds.
African journal of agricultural research 08/2015; 10(30):2859-2865. DOI:10.5897/AJAR2015.9569 · 0.26 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A salinidade é fator limitante para que ocorra germinação na maioria das espécies sendo necessários estudos que avaliem a interação entre plantas e o ambiente salino ao qual estão associadas. O presente estudo consistiu em avaliar a germinação e características de vigor em Salvia splendens submetidas à salinidade. As sementes foram expostas a diferentes potenciais osmóticos, simulando condições de estresse salino, provocado por NaCl, CaCl2 e KCl nos potenciais de 0; -0,4; -0,8; -1,2; -1,6 e -2,0 MPa. De modo geral, pode-se observar que o CaCl2 resultou em melhores resultados para todas as variáveis analisadas, provavelmente ligado ao efeito positivo do Ca2+ no metabolismo celular, permitindo germinação 60,81% no potencial osmótico de -1,35 MPa.
[Show abstract][Hide abstract] ABSTRACT: Despite the economic importance of Crambe abyssinica, the present study is the first report on bees that occur with this species, and could aid in developing alternative methods for controlling insect pests without seriously impacting pollinators. The present study examined the following questions: (1) Which species are potential pollinators of C. abyssinica? (2) How do environmental conditions influence pollinator visitation fluctuations? Insects were sampled on a weekly basis between 08:00 and 16:00 during five weeks of flowering. When the results of analyses of variance were significant, the data was adjusted using regression equations at a 5% level of probability; the environmental variables were examined using Pearson's correlation coefficient. Apis mellifera, Geotrigona mombuca, Exomalopsis (Exomalopsis) fulvofasciata, Plebeia sp. and Dialictus sp. were observed visiting C. abyssinica flowers. A. mellifera and G. mombuca were observed to be potential pollinators, with the former demonstrating visitation peaks during flowering weeks II and IV at 12:00 and 08:00, respectively and the latter visiting during weeks III and IV at 12:00 and 10:00, respectively. Environmental factors such as temperature, relative humidity, and wind speed have different effect on the activity of bees.
Anais da Academia Brasileira de Ciências 03/2015; 87(1):137-45. DOI:10.1590/0001-3765201520130365 · 0.73 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Resumen El objetivo de este trabajo consistió en evaluar el efecto de los pre-tratamientos con giberelinas, la humedad inicial del sustrato y la temperatura de incubación sobre la germinación de Psidium guineense Swartz. Las semillas se sometieron a cuatro tratamientos previos con giberelina (GA 3) (50 y 100 mg L -1) y agua destilada durante 24 horas y un control. La siembra se hizo en papel Germitest ® humedecido con agua destilada a niveles de humedad correspondientes a 1,5 y 2,5 veces el peso de papel seco. Luego las semillas se incubaron a temperaturas constantes (25 y 30 °C) y a temperaturas variables (20-30 °C). El procedimiento estadístico utilizado fue un diseño factorial 4 x 2 x 3 (pre-tratamiento x humedad inicial del sustrato x temperatura) completamente al azar con cuatro repeticiones de 25 semillas cada una. La germinación de las semillas y el crecimiento de las plántulas de P. guineense no se vieron afectados por los tratamientos pre-germinación. Para una germi-nación y crecimiento óptimos las semillas de P. guineense deberían sembrarse a temperaturas de 20-30 o 25 °C y a una humedad del sustrato de 1,5 o 2,5 veces la masa del papel seco. Summary Efecto de pre-tratamientos sobre la germinación de semillas y crecimiento de plántulas Psidium guineense Swartz
[Show abstract][Hide abstract] ABSTRACT: The aim of this research was to evaluate the quality and photosynthetic metabolism of "uvaia" seedlings (Eugenia pyriformis Cambess.) on different substrates and water regimes. The seeds were sown in tubes of 50 x 190 mm in the following substrates: Sand (S), Latosol + Sand (L + S) (1:1), Latosol + Sand + Semi Decomposed Poultry Litter (L + S1 + PL) ( 1:1:0.5), Latosol + Sand + Semi Decomposed Poultry Litter (L + S2 + PL) (1:2:0.5), Latosol + Bioplant® (L + B) (1:1), and the water levels assessed were 50, 75 and 100% of water retention capacity. At 60, 90, 120 and 150 days the seedlings were evaluated according to their chlorophyll index, leaf area (cm2) and Dickson Quality Index (DQI) and at 150 days their internal concentration of carbon (mol m-2 s-1), stomatal conductance (mol m-2 s-1), transpiration rate (mmol m-2 s-1), photosynthesis (µmol m-2 s-1) and efficiency of water use (µmol de CO2 / mmol de H2O). Until their 150th days, the seedlings had higher quality and photosynthetic metabolism when cultured with substrates containing latosol + sand + poultry litter on the two variations assessed and water retention capacity of 50%.
Anais da Academia Brasileira de Ciências 11/2014; DOI:10.1590/0001-3765201420130249 · 0.73 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to evaluate the effect of pre-treatments on overcoming dormancy of A. coriacea seeds. Seeds were processed and stored in polyethylene bags at temperatures of at -18°C (42% RH), 5°C (34% RH), 15°C (60% RH) and 25°C (34% RH), during 0, 30, 60, 90, 120 and 150 days. After storage, seeds were immersed in 350 mg.L-1 gibberellic acid for 144 hours. Sowing was carried out in plastic bags containing Red Latosol + Bioplant®. Moisture content, emergence percentage, emergence speed index, length and dry mass of seedlings, were evaluated. The experimental design was completely randomized in a factorial with four replications of 50 seeds each. The seed storage at 5°C and subsequent immersion in gibberellic acid was efficient to reach high percentage, emergence speed and plant growth. A. coriacea seeds showed non-deep simple morphophysiological dormancy wherein the physiological component can be overcome after the seeds are storage at 5°C for a maximum period of 53 days and subsequent immersed in exogenous GA (350 mg.L-1 for 144 hours).
Anais da Academia Brasileira de Ciências 10/2014; DOI:10.1590/0001-3765201420130276 · 0.73 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Hancornia speciosa is a native tree species of the Brazilian Cerrado whose seeds are desiccation sensitive. In this study, we aimed to evaluate drying and osmotic conditioning in H. speciosa seeds. We used fresh seeds with 48% moisture content, which were slowly dried until they attained contents of 20%, 15%, 10% and 5%. To evaluate osmotic conditioning, the seeds were imbibed in 12 mL osmotic solutions at 0.0; -0.2; -0.4 and -0.6 MPa for two days. After that, they were dehydrated until their original moisture content. The experiments were carried out in a completely randomized design with four repetitions with 50 seeds each. Reduction in moisture content from 20% to 5% decreased the physiological potential of seeds. H. speciosa seeds do not require osmotic priming with PEG solutions, because imbibition of seeds in osmotic solutions of up to -0.6 MPa results in reduction of germination rate and seedling length.
Floresta e Ambiente 01/2014; 21(1):62-68. DOI:10.4322/floram.2014.012
[Show abstract][Hide abstract] ABSTRACT: Objetivou-se avaliar os efeitos de diferentes recobrimentos e temperaturas de armazenamento na conservação de laranjas Champagne. Após refrigeração e sanitização, os frutos foram submetidos aos seguintes tratamentos: 1) controle, sem recobrimento; 2) frutos recobertos com fécula de mandioca a 2% (m/v); 3) frutos recobertos com fécula de mandioca a 4% (m/v); 4) embalagem com filme de PVC esticável; 5) embalagem em saco plástico de polietileno de baixa densidade. Estes frutos foram, em seguida, armazenados em três diferentes temperaturas: ambiente (25ºC / 70 ± 5% UR) e em câmara fria a 3ºC e a 8ºC, com 85 ± 5% UR. Determinou-se a perda de massa pelos frutos; no suco, foram determinados o pH e os sólidos solúveis (SS), a acidez titulável, os açúcares totais e o ácido ascórbico. As amostragens foram realizadas a cada 4 dias, durante 24 dias, nos frutos armazenados em condição ambiente, e a cada 10 dias, durante 60 dias de armazenamento, nos frutos mantidos em câmara fria. Os frutos armazenados a 3ºC apresentaram menor perda de massa. Os frutos do controle e os revestidos com fécula, independentemente da temperatura de estocagem, tiveram perdas maiores do que aqueles embalados em filme de PVC e polietileno. A acidez apresentou redução ao longo do armazenamento em todas as temperaturas estudadas e sem diferenças entre os revestimentos/embalagens. Os tratamentos e o período de armazenamento, independentemente da temperatura, não influenciaram nos resultados de pH, teores de SS, açúcares totais e ácido ascórbico. Os frutos refrigerados a 3ºC mantiveram a qualidade por até 60 dias, desde que acondicionados com polietileno e PVC, enquanto que, sob a temperatura ambiente, a qualidade dos frutos embalados com estes filmes foi mantida por até 20 dias. Frutos embalados com o filme de polietileno apresentaram sinais de podridão e odor estranho a partir do 20º dia, quando armazenados a 25ºC, e a partir do 50º dia, quando armazenados a 8ºC.
[Show abstract][Hide abstract] ABSTRACT: The interest for crambe emerged from its superiority in relation to soybean and other oilseeds for vegetable oil production and its great adaptability for the direct planting. This work aimed to evaluate the storage of the crambe seeds in different packagings and environments. Polyethylene bags and rigid plastic packaging with hermetic sealingwere tested in the following conditions: laboratory (25 ± 2 ºC e 60% RH) and dry and cold chamber (15 ± 2 ºC e 45% RH), during 0, 30, 60, 90, 120, 150 and 180 days (May to November, 2010). Seed water content, first count, seed germination, germination speed index and seed germination medium time were evaluated monthly. The experiment was carried out with four replications using 50 seeds in each treatment. Initially, seeds showed 60% germination and 7.0% moisture content. The packagings and environments tested allowed alterations in seed water content which, possibly, provided the beginning of seed deterioration, which was assessed through the reduction of the first count, speed index and increase in the germination average time. However, the treatments and the storage periods did not influence the seed germination. In general, crambe seeds can be stored in impermeable packaging during 180 days at 15 ± 2 ºC and 45% RH.
Revista Ceres 10/2013; 60(5):646-652. DOI:10.1590/S0034-737X2013000500007
[Show abstract][Hide abstract] ABSTRACT: The knowledge on biometric aspects of fruits and seeds and their influence on germination are important for the production and properties of native species. This study aimed at evaluating the influence of fruit and seed size on the germination and vigor of Campomanesia adamantium seeds. For the biometric characterization, 120 fruits were randomly selected and visually divided into four classes, with predominance for size, in which longitudinal and transversal diameters and mass of seeds were measured. The seed characterization was carried out in 30 fruits of each class, by determining the number of whole, empty and total seeds of every fruit. The seeds physiological potential, according to fruit size, was evaluated with the aid of the following tests: imbibition curve, moisture content, germination percentage and speed index, seedling length, total fresh and dry matter of seedlings. A completely randomized design, with four treatments, was used. Fruits were respectively classified according to their longitudinal and transversal diameters as small (12.71 mm; 12.46 mm), medium small (15.38 mm; 15.01 mm), medium large (18.84 mm; 18.02 mm) and large (22.74 mm; 22.36 mm). The classes of small, medium small and medium large fruits presented seeds with higher germination percentage and speed index, while seedlings with higher biomass accumulation were observed for large fruits.
[Show abstract][Hide abstract] ABSTRACT: Canafístula is an important native forest species, found in Cerrado, which still lacks on nutritional information and obtaining quality seedlings. Therefore, this study aimed to evaluate the effects of the addition of nitrogen and phosphorus on initial growth and seedling quality of canafístula (Peltophorum dubium Spreng. Taub.) grown in Oxisol. The experiment was carried out in 4 dm3 pots with treatments arranged in 4x4 factorial scheme, with four N levels (0, 20.82, 41.64 and 62.46 mg kg-1 N) and four P levels (0, 41.72, 83.72 and 125.16 mg kg-1 of P2O5) in a randomized block design with three replications. Were evaluated the growth characteristics (height, stem diameter and dry mass of shoots and roots) and quality parameters of seedlings (ratio height/diameter RAD; ratio dry mass of shoot / root dry weight RPAR, and Dickson Index). There was significant interaction between N and P for all growth characters and quality parameters evaluated. The highest level of N and P showed higher growth of seedlings. However, regarding the quality of seedlings, the Dickson index indicated that the phosphorous is the most important element.
Revista Árvore 08/2013; 37(4):717-724. DOI:10.1590/S0100-67622013000400015 · 0.36 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Obtaining native seedlings requires information about seeds harvest time, storage and luminosity conditions, germination and types of substrate, among others. This study aimed at evaluating the luminosity demands for the initial growth of Caesalpinia ferrea Mart. ex. Tul. var. leiostachya Benth (Fabaceae-Caesalpinioideae) seedlings submitted to different shading levels, at 60 days after transplant (DAT). The experimental design was completely randomized, in 3x5 factorial scheme (three shading levels: 0%, 50% and 70%; and five evaluation times: 60, 90, 120, 150 and 180 DAT), with four replications of 10 seedlings per experimental unit. Plants grown under the shading level of 70% presented the highest contents for total chlorophyll (38.79 µg cm-2), leaf area ratio (51.54 g cm-2), relative growth rate (0.0322 g g-1 day-1) and leaf weight ratio (0.2708 g g-1). The highest values for stem height (110.34 cm) and base diameter (9.3 mm), and root (11.13 g), leaf (5.59 g) and shoot (16.05 g) dry matter, as well as leaf area (705.25 cm2), were observed in the plants cultivated under the shading level of 50%. No differences were observed for root growth, specific leaf weight, net assimilation rate and specific leaf area, concerning the different shading levels tested (averages of 9.3 cm, 0.0082 g cm-2, 0.0006 g cm-2 day-1 and 186.24 g cm-2, respectively). The Caesalpinia ferrea seedlings presented a better growth rate when cultivated under the shading level of 50%.