STORAGE OF Handroanthus umbellatus SEEDS

A manuten\ue7\ue3o da viabilidade das sementes por meio do armazenamento, em condi\ue7\uf5es de ambiente controlado, representa uma das linhas de pesquisa mais importantes para esp\ue9cies florestais com sementes pouco longevas como as das esp\ue9cies do g\ueanero Handroanthus . Nesse trabalho procurou-se identificar o comportamento das sementes quanto \ue0 longevidade e \ue0 condi\ue7\ue3o mais adequada para o armazenamento de sementes de Handroanthus umbellatus. As sementes foram secas at\ue9 6,3% de teor de \ue1gua e submetidas aos seguintes tratamentos de armazenamento: acondicionamento em sacos de papel unifoliado (perme\ue1vel) em condi\ue7\uf5es n\ue3o controladas de temperatura e umidade relativa de laborat\uf3rio (testemunha) e multifoliados (semiperme\ue1vel) nas temperaturas de -18\ub0C, 1\ub0C e 25\ub0C. As sementes armazenadas foram avaliadas trimestralmente at\ue9 24 meses quanto ao teor de \ue1gua, \ue0 porcentagem de germina\ue7\ue3o e ao vigor por meio do teste da primeira contagem. As sementes de Handroanthus umbellatus s\ue3o ortodoxas, mas de baixa longevidade em condi\ue7\uf5es naturais, pois se mant\ueam vi\ue1veis no ambiente por menos que 5 meses. A melhor condi\ue7\ue3o para a conserva\ue7\ue3o de sementes dessa esp\ue9cie foi obtida com o armazenamento a -18\ub0C em sacos multifoliados, que manteve praticamente inalterada a qualidade fisiol\uf3gica das sementes por 24 meses. Palavras-chave: Tabebuia umbellata; Handroanthus eximius; conserva\ue7\ue3o de sementes; vigor.Seed storage under controlled environmental conditions represents one of the most important lines of research to be applied on short-lived forest species as Handroanthus . The present research aimed to identify the most suitable seed storage conditions and longevity behavior of Handroanthus umbellatus seeds subject to the following storage treatments: packaging permeable paper bags under a no-controlled laboratory temperature and humidity (control) and multiwall semipermeable bag at temperatures of -18 \ub0C, 1 \ub0C and 25 \ub0C. Seeds were dried to 6.3% of water content. Stored seeds were evaluated every three months until 24 months for water content, germination percentage and vigor utilizing first counting test. Seeds of T. umbellata are orthodox, with low longevity under natural conditions, once they remain viable for less than 5 months. The best conditions of seed preservation of these species were obtained by storage at -18\ub0 C in multiwall bags. Under these conditions physiological seed quality remains unchanged for a 24-month period

ARMAZENAMENTO DE SEMENTES DE IPÊ-AMARELO-DO-BREJO (Handroanthus umbellatus (Sond.) Mattos. Bignoniaceae)

http://dx.doi.org/10.5902/1980509815725Seed storage under controlled environmental conditions represents one of the most important lines of research to be applied on short-lived forest species as Handroanthus. The present research aimed to identify the most suitable seed storage conditions and longevity behavior of Handroanthus umbellatus seeds subject to the following storage treatments: packaging permeable paper bags under a no-controlled laboratory temperature and humidity (control) and multiwall semipermeable bag at temperatures of -18 ºC, 1 ºC and 25 ºC. Seeds were dried to 6.3% of water content. Stored seeds were evaluated every three months until 24 months for water content, germination percentage and vigor utilizing first counting test. Seeds of T. umbellata are orthodox, with low longevity under natural conditions, once they remain viable for less than 5 months. The best conditions of seed preservation of these species were obtained by storage at -18° C in multiwall bags. Under these conditions physiological seed quality remains unchanged for a 24-month period.http://dx.doi.org/10.5902/1980509815725A manutenção da viabilidade das sementes por meio do armazenamento, em condições de ambiente controlado, representa uma das linhas de pesquisa mais importantes para espécies florestais com sementes pouco longevas como as das espécies do gênero Handroanthus. Nesse trabalho procurou-se identificar o comportamento das sementes quanto à longevidade e à condição mais adequada para o armazenamento de sementes de Handroanthus umbellatus. As sementes foram secas até 6,3% de teor de água e submetidas aos seguintes tratamentos de armazenamento: acondicionamento em sacos de papel unifoliado (permeável) em condições não controladas de temperatura e umidade relativa de laboratório (testemunha) e multifoliados (semipermeável) nas temperaturas de -18ºC, 1ºC e 25oC. As sementes armazenadas foram avaliadas trimestralmente até 24 meses quanto ao teor de água, à porcentagem de germinação e ao vigor por meio do teste da primeira contagem. As sementes de Handroanthus umbellatus são ortodoxas, mas de baixa longevidade em condições naturais, pois se mantêm viáveis no ambiente por menos que 5 meses. A melhor condição para a conservação de sementes dessa espécie foi obtida com o armazenamento a -18ºC em sacos multifoliados, que manteve praticamente inalterada a qualidade fisiológica das sementes por 24 meses

Tratamentos pré-germinativos em sementes de cajá (Spondias mombin L.)

The germination of Spondias mombin seeds is slow and irregular – it takes between 6 and 24 months for the process to complete.  This causes the plantlets producer serious difficulties since the plantlets are more expensive to produce and frequently are of different heights.  The objective of this project was to establish techniques and strategies of Spondias mombin seed selection to promote and speed up germination. Having that in mind, two experiments were carried out. In the first, seeds (which are of the nucular type) of two colors (beige and brown) and four classes of size (small, medium-small, medium-large, and large) had their length, width, and weight determined. In the second experiment, the color (beige and brown) classified seeds were submitted or not to a fungicide treatment and to mechanical scarification of the endocarp (base, apex, lateral, and no scarification). The experiments were distributed according to a completely random design with four 20 seeds replications in the following factorial arrangements: 4x2 (size x color) and 4x2x2 (scarification x color x fungicide). Seedling emergence in sand, first count of germination, and mean time for germination were weekly determined up to 730 days; these evaluations were based on the determination of normal seedlings counting.  Choosing brown and medium-large seeds is an efficient strategy to accelerate seedling emergence. Treating the seeds with fungicide was harmful to the germination process.  The lateral scarification of brown seeds permitted a reduction in the period necessary for the completion of germination from 489 to 336 days.As sementes de cajá apresentam germinação lenta e desuniforme, pois o processo normalmente tem duração de seis meses e dois anos. Tal característica constitui-se em entrave para os viveiristas, pois onera os custos de produção e resulta em mudas com tamanhos diversos. O objetivo deste trabalho foi estabelecer técnicas e estratégias de seleção de sementes de cajá (Spondias mombin L.) que promovam ou acelerem a germinação. Para tanto, foram realizados dois experimentos. No primeiro, foram avaliadas sementes (nuculânios) de duas cores (bege e marrom) e quatro classes de tamanho (pequena, média-pequena, média-grande e grande) caracterizadas por meio do comprimento, largura e massa. No segundo experimento, as sementes classificadas quanto à cor (bege e marrom) foram submetidas ou não à aplicação de fungicida e à escarificação mecânica do endocarpo (base, ápice, lateral e sem escarificação mecânica). Os experimentos foram instalados em delineamento inteiramente casualizado com quatro repetições de 20 sementes, nos seguintes arranjos fatoriais: 4 x 2 (tamanho x cor) e 4 x 2 x 2 (escarificação x cor x fungicida). Avaliou-se a emergência de plântulas em areia, primeira contagem e o tempo médio da emergência. Em ambos os estudos, a emergência foi avaliada semanalmente, até os 730 dias. Concluiu-se que a seleção de sementes marrons e média-grandes (31 x 18 cm e 2,16 g) constituiu-se em uma estratégia eficiente para aumentar e acelerar a emergência de plântulas. O tratamento das sementes com fungicida (metalaxil-M+fludioxonil) foi prejudicial ao processo germinativo. A utilização de sementes marrons e escarificadas na lateral possibilitou a aceleração da germinação (tempo médio de 489 para 336 dias)

Vermiculita como substrato para o teste de germinação de sementes de barbatimão

The objective of this research was to evaluate the use of vermiculite as a substrate for the germination test of ‘barbatimão’ seeds and to establish what would be the best granulometry and the best moisture intensity to germinate ‘barbatimão’ seeds. Four replications of 50 seeds were previously scarified with H2SO4 for 60 minutes. Afterwards, the following germination substrates were evaluated: paper rolls moistened with water equivalent to 2.5 times the weight of the dry paper (control); micron, super thin, thin and average sized vermiculite moistened with 0.5, 1.0, 1.5 and 2.0 times the weight of the dry paper. The germination temperature was 30°C. The percentage of normal seedlings was obtained seven days after sowing (first count) and, then, weekly (up to 28 days). Average time and relative distribution of germination were calculated. It was concluded that the germination of ‘barbatimão’ seeds can be carried out with either fine vermiculite moistened with water equivalent to 2.0 times the weight of the dry paper or average sized substrate moistened with water equivalent to 0.5 to 2.0 times the weight of dry paper. These treatments resulted in higher and faster germination (21 days), similarly to the paper roll method.O objetivo deste trabalho foi avaliar o desempenho da vermiculita como substrato para o teste de germinação e estabelecer qual granulometria e intensidade de umedecimento deste substrato seria mais favorável à germinação de sementes de barbatimão. A semeadura foi realizada com quatro repetições de 50 sementes (escarificadas com H2SO4/60 min) em rolo de papel (RP) umedecido com 2,5 vezes a massa em água (testemunha) e vermiculita nas granulometrias mícron (MI), superfina (SF), fina (F) e média (M) umedecida com 0,5; 1,0; 1,5 e 2,0 vezes a sua massa em água. O teste de germinação foi conduzido a 30°C, avaliando-se a primeira e a última contagens aos 7 e 28 dias após a semeadura realizando-se avaliações semanais das plântulas normais. Foi calculado o tempo médio e a frequência relativa de germinação. O teste de germinação de sementes de barbatimão pôde ser realizado em vermiculita F (umedecida com 2,0 vezes a sua massa em água) ou M (umedecida com 0,5 até 2,0 vezes a sua massa em água) por possibilitarem a máxima germinação em menor tempo (21 dias), de modo similar ao RP

Production fields and physiological quality of Panicum maximum jacq. cv. mombasa seeds

The physiological quality of seeds is influenced by the climatic factors of production fields. The identification of the best conditions of P. maximum cv. Mombasa production fields allows the improvement of the seed sector. The aim of this work was to identify which climatic conditions of production fields can affect the physiological quality of P. maximum cv. Mombasa seeds. Nineteen plots from states of São Paulo (six from municipalities of Auriflama and three from Guzolândia) and Goiás (eight from Quirinópolis and two from Serranópolis), were collected by soil sweeping. The following parameters were evaluated: water content, germination rate, first germination count and germination rate index, seedling emergence in sand and field. Completely randomized design was used for all variables, with the exception of seedling emergence in field, since this variable required block design. Means were compared by the Scott-Knott test, at 5% probability. For the identification of the influence of climatic conditions on the physiological quality of seeds, multivariate statistical analysis was applied through Group and Principal Component Analysis. Production fields of Panicum maximum cv. Mombasa seeds presenting maximum temperatures above 32 ºC at flowering and natural fall stages produce seeds of low physiological quality. Production fields in which precipitation and high temperatures occur during natural fall and harvest of P. maximum cv. Mombasa seeds are not favorable to the production of seeds with high physiological quality

Seed conditioning process in the sanitary quality of marandu grass seeds

The purpose of seed conditioning process is to separate seeds and their associated structures into different fractions and retain only good and healthy seeds. Thus, the aim of this study was to evaluate the effects the stages of seed conditioning have on the sanitary quality of marandu grass seeds. The seeds were sampled before and during the seed conditioning process, i.e., after exiting the air-screen cleaner and sieves (seeds discharged from the top, middle and bottom sieves), the first gravity separator (seeds drifting around the table, upper and intermediate discharge) and second gravity separator (upper, intermediate and lower discharge). The sanitary analysis was performed using the filter paper method with and without surface disinfestation of the seeds, which were incubated at 20±2°C, with a photoperiod of 12 hours for seven days. The experiment was conducted in a completely randomized design, in a 2x6 factorial scheme (surface disinfestation x stages of the seed conditioning process) and ten replications. The data was submitted to analysis of variance, using the F test and, when significant, the means of the treatments were compared using the Tukey test at 5% probability. It was concluded that it is not possible to improve the sanitary quality of marandú grass seeds through the seed conditioning process

EFFECT OF SHADING AND SUBSTRATE ON THE GERMINATION AND SEEDLING GROWTH OF Acacia mangium AND Acacia mearnsii

A germina\ue7\ue3o r\ue1pida e uniforme das sementes, seguida por pronta emerg\ueancia das pl\ue2ntulas, s\ue3o caracter\uedsticas altamente desej\ue1veis na forma\ue7\ue3o de mudas. Estudos com a finalidade de viabilizar a utiliza\ue7\ue3o de res\uedduos org\ue2nicos como o lodo de esgoto e a casca de pinus na cadeia produtiva representam uma demanda atual. O objetivo deste trabalho foi identificar condi\ue7\uf5es de sombreamento e substrato favor\ue1veis ao processo de germina\ue7\ue3o das sementes e crescimento de pl\ue2ntulas de Acacia mangium e Acacia mearnsii . Ap\uf3s a supera\ue7\ue3o da dorm\ueancia, por imers\ue3o em \ue1gua quente, as sementes foram semeadas em tr\ueas tipos de substratos: substrato comercial Plantmax florestal (testemunha), casca de pinus e mistura de casca de pinus com bioss\uf3lido (1:1). Os tubetes foram colocados em viveiro, sob duas condi\ue7\uf5es de sombreamento: 50% e 30%, e a pleno sol (0%), como testemunha. Os par\ue2metros avaliados foram: velocidade e porcentagem de germina\ue7\ue3o (diariamente, at\ue9 30 dias) e comprimento da parte a\ue9rea de pl\ue2ntulas (semanalmente, de 75 a 150 dias). O delineamento experimental utilizado foi o inteiramente casualizado com os tratamentos dispostos em um fatorial 3 x 3, os resultados foram submetidos \ue0 an\ue1lise de regress\ue3o e teste T. Maiores porcentagens de germina\ue7\ue3o foram obtidas na semeadura de Acacia mangium em casca de pinus sob 30% de sombreamento, e substrato comercial sob 30 e 50% de sombreamento e para Acacia mearnsii em casca de pinus sob 50% de sombreamento, ou substrato comercial a pleno sol. Para ambas as esp\ue9cies, as pl\ue2ntulas cresceram mais rapidamente e atingiram maior tamanho final no substrato casca de pinus com bioss\uf3lido e em qualquer condi\ue7\ue3o de sombreamento (30 e 50 %) e a pleno sol, antecipando a produ\ue7\ue3o de mudas.The speed and uniform germination of seeds, followed by the prompt seedling emergence, are highly desirable characteristics in seedling production. Studies aiming to enable the use of organic waste such as sewage sludge and pine bark in the supply chain represent a current demand. The aim of this study was to identify conditions of shading and substrate which are more favorable to the process of seed germination and seedling growth of Acacia mangium and Acacia mearnsii . After overcoming dormancy in hot water, the seeds were sown in three substrates: substrate plantmax commercial forest (control), pine bark and pine bark mixed with biosolids (1:1). The tubes were placed in a tree nursery under three shading conditions: 50%, 30% and 0% (full sun). The evaluated parameters were: speed and germination percentage (daily until 30 days) and shoot length of seedlings (weekly from 75 to 150 days). The experiment was a completely randomized design with treatments in a factorial 3 x 3 and the results were submitted to regression analysis. The highest germination was obtained in the sowing of Acacia mangium in pine bark at 30% shading and commercial substrate at 30 and 50% shading for Acacia mearnsii in pine bark under 50% shading or commercial substrate in full sun. For both species, seedlings grew faster and reached larger size in the final substrate of pine bark with biosolids and in any condition of shading (30 e 50 %) and full sun, anticipating the production of seedlings

Vigor tests in assessing the quality of signal grass seeds

The correct assessment of the physiological quality of seed lots is necessary for the quality control program of companies. For such purpose, tests that detect differences in the physiological potential of seed lots and that meet the minimum market requirements. Thus, the study was conducted towards assessing the efficiency of laboratory tests in differentiating the quality of Brachiaria brizantha cv. Xaraés seed lots. Seeds from nine lots were assessed regarding water content, germination, first germination count, electrical conductivity and seedling emergence in sand in the laboratory (normal seedlings, first count and germination rate index), and the results were compared with those from the seedling emergence test conducted in the field. The experimental design used was completely randomized, with four replicates, and the Pearson correlation coefficient between the values from the germination, vigor and field seedling emergence tests was determined. The germination and seedling emergence in sand tests and the seedling emergence rate index efficiently assess the physiological quality of Brachiaria brizantha cv. Xaraés seed lots, providing data similar to those from seedling emergence in the field