Charline Zaratin Alves

Adequação da metodologia para o teste de germinação de sementes de pitaia vermelha

Hylocereus undatus (Haw.), popularly known as red pitaya is a cactus for which it has been registered an increase in consumption in recent years and, being as yet little explored, several aspects related to its propagation are still unknown. Yet, there are no criteria for the performance of germination tests for seeds of this species published in Rules for Seed Analysis. Accordingly, the objective of this research was to adapt the methodology to the substrate, temperature and time of initial and final count for the germination test. Four substrates were tested (rolled paper, sand, vermiculite and soil) and four temperatures (20, 25, 30 e 20-30°C).The effect of substrates on the seeds germination performance was evaluated by the germination test and first count installed with four replicates of 50 seeds. The number of seedlings was counted daily until they achieved stability. The percentage of seed germination was evaluated at the end of the experiment, considering the normal and abnormal seedlings and dead seeds. It was concluded that the germination test of red pitaya seeds must be performed at constant temperature of 25°C in rolled paper, with initial and final counts at five and ten days after sowing, respectively.

Seedling emergence in Schizolobium amazonicum Huber ex Ducke (Caesalpinaceae) in different substrates and shading

Parica (Schizolobium amazonicum Huber ex Ducke) e uma especie da floresta amazonica que vem sendo intensamente utilizada nos programas de reflorestamento, tanto por ser de crescimento rapido como pelo bom comportamento em plantios homogeneos. O objetivo do trabalho foi avaliar a influencia de substratos e sombreamento sobre a emergencia e o vigor de plântulas de parica. O delineamento experimental foi o inteiramente casualizado, com quatro repeticoes, em arranjo fatorial 10 x 2 (substrato e sombreamento). Os substratos comerciais utilizados foram casca de coco e terra vegetal, em mistura com casca de arroz, areia, po de serra fresco e po de serra curtido. Foram avaliados a emergencia de plântulas, o indice de velocidade de emergencia, o comprimento das raizes e da parte aerea, a materia seca das raizes e da parte aerea, a frequencia relativa e o tempo medio de emergencia. Os substratos terra vegetal, casca de coco e casca de coco + areia em ambiente com 50% de sombreamento, e terra vegetal, terra vegetal + areia e casca de coco + areia a pleno sol proporcionaram os melhores resultados. A areia e o po de serra fresco, ambos em mistura com casca de coco, podem ser usados na fase inicial de viveiro, devendo as mudas ser transplantadas para outro substrato ou o campo apos 40 dias. A casca de arroz in natura nao deve ser misturada com outros materiais para a utilizacao como substrato.Parica (Schizolobium amazonicum Huber ex Ducke) e uma especie da floresta amazonica que vem sendo intensamente utilizada nos programas de reflorestamento, tanto por ser de crescimento rapido como pelo bom comportamento em plantios homogeneos. O objetivo do trabalho foi avaliar a influencia de substratos e sombreamento sobre a emergencia e o vigor de plântulas de parica. O delineamento experimental foi o inteiramente casualizado, com quatro repeticoes, em arranjo fatorial 10 x 2 (substrato e sombreamento). Os substratos comerciais utilizados foram casca de coco e terra vegetal, em mistura com casca de arroz, areia, po de serra fresco e po de serra curtido. Foram avaliados a emergencia de plântulas, o indice de velocidade de emergencia, o comprimento das raizes e da parte aerea, a materia seca das raizes e da parte aerea, a frequencia relativa e o tempo medio de emergencia. Os substratos terra vegetal, casca de coco e casca de coco + areia em ambiente com 50% de sombreamento, e terra vegetal, terra vegetal + areia e casca de coco + areia a pleno sol proporcionaram os melhores resultados. A areia e o po de serra fresco, ambos em mistura com casca de coco, podem ser usados na fase inicial de viveiro, devendo as mudas ser transplantadas para outro substrato ou o campo apos 40 dias. A casca de arroz in natura nao deve ser misturada com outros materiais para a utilizacao como substrato.

Teste de germinação em sementes de Cucumis metuliferus E. Mey

The kiwano (Cucumis metuliferus E. Mey) is a cop of wide geographical distribution, with a significant increase in relation to marketing worldwide due not only to his life being too long at room temperature, as well as to the constant search market consumer for exotic products. Thus, demand and marketing of its seeds are increasing, creating the need for the establishment of state and federal standards and the development of appropriate methodologies for evaluating the quality of them. Thus, the objective of this study was to determine the methodology for the substrate, temperature and time count for the germination test on Kiwano seeds. The evaluations consisted of four substrates: paper roll, on paper, in sand and on sand at four temperatures: 20, 25 e 30°C constant and 20-30°C alternating. The effect of substrate and temperature on seed performance was evaluated using germination, speed index and mean germination time. The experiment was conducted in a completely randomized design with treatments arranged in a factorial 4x4 (substrates x temperatures) with four replications. The test germination in seeds of kiwano should be done on the paper roll at constant temperature of 25°C or alternating 20-30°C, with counting starting and ending in the fifth and tenth day, respectively.

Germinação de sementes de urucum em função de métodos de superação de dormência e temperaturas

Bixa orellana L. is a perennial plant known as annatto or achiote, which belongs to the Bixaceae family and is widely used in cooking, due to its properties of natural dye, whose germination is affected by its own characteristics. This study aimed at elucidating the dormancy mechanism of annatto seeds and evaluating the effect of different methods for breaking it, under different germination temperatures. The scarification methods were: chemical (with concentrated sulfuric acid and ethanol, under immersion for five minutes), physical (scarification with sand paper) and thermic (in water at 70oC, for two minutes, and then under temperatures of 20oC, 25oC, 30oC and 20-30oC, for germination). The amount of water absorbed by seeds, and percentage, first counting and germination rate, as well as hypocotyl and taproot length, were evaluated. For the seeds that did not germinate, the tetrazolium test was applied to verify their viability. It was concluded that the treatments used for dormancy breaking did not affect the annatto seeds viability. Scarification with sand paper or sulfuric acid, for five minutes, and temperatures of 25oC or 20-30 o C are recommended.

Methods of accelerating and standardising the emergence of seedlings in Schizolobium amazonicum.

The intense dormancy seen in seeds of Schizolobium amazonicum, known locally as parica, makes the formation process of seedlings difficult. The aim of this work was to test procedures to accelerate and standardise the emergence of seedlings in the parica. The seeds used were collected from various matrices in the Antimary State Forest, in the Brazilian state of Acre. Treatments consisted of intact seeds (control), scarification with concentrated sulphuric acid (immersion for 5, 10, 15, 20, 25, 30, 35, 40, 45 and 50 min), immersion in heated water (60 oC, 80 oC and 100 oC ), scarification of the basal part of the seed with sandpaper, scarification with a punch by means of perforations in the largest lateral portion of the husk, and scarification with an electric emery grinder on the side of the husk. The effects of the treatments were evaluated using seedling emergence (EP) and the emergence speed index (EVI) at six observation times, as well as the relative frequency and average time of emergence for the best results. The statistical design was completely randomised with four replications in a factorial scheme for EP, and a single array for the IVE. Maximum EP can be achieved in less time by using the punch, immersion in boiling water (100oC) and the electric grinder.

Envelhecimento acelerado em sementes de mogno

A importância economica do mogno ressalta a relevância da analise do vigor de suas sementes visando a formacao de mudas com qualidade. O objetivo foi avaliar a influencia de diferentes temperaturas e periodos de exposicao do teste de envelhecimento acelerado em sementes de mogno. As variaveis analisadas foram: teor de agua, emergencia de plântulas, indice de velocidade de emergencia, frequencia relativa e tempo medio de emergencia apos o envelhecimento acelerado [(39; 41; 43 e 45 °C, durante zero (testemunha), 24; 48; 72 e 96 horas]. O vigor de sementes de mogno pode ser avaliado por meio do teste de envelhecimento acelerado nas temperaturas de 39 oC/96 horas e 43 oC por 48 ou 96 horas. A combinacao 43 oC/48 horas permite reduzir o tempo de execucao das avaliacoes de sementes de mogno. O indice de velocidade de emergencia e uma variavel adequada para avaliar a influencia do envelhecimento acelerado sobre sementes de mogno.

Metodologia para a condução do teste de germinação em sementes de goiaba

Despite the knowledge that commercial propagation of the guava should be asexual, the use of seeds becomes mandatory in breeding programs and the production of rootstock, however few studies are found on methodologies for analysis of the seeds of this species, a fact which can be proved by the Rules for Seed Analysis, where there is no recommendation for a germination test. Thus, the aim of this work was to determine a methodology in terms of temperature, substrate and counting period for the germination test in guava seeds. The temperatures under evaluation were: constant at 20, 25 and 30 °C , and alternating 20 to 30 °C, with the following substrates: paper roll, on paper, in sand and on sand. The effect of temperature and substrate on seed performance was evaluated by the germination test, speed index and mean germination time. The experiment was set up in a completely randomised design, with the treatments distributed in a 4 x 4 factorial scheme (temperature x substrate), with four replications. Under the conditions being tested, it was found that the germination test in guava seeds can be carried out at an alternating temperature of 20-30 °C, using paper roll, on paper or on sand as substrate, and with the final count taken 23 days after sowing.

QUALIDADE FISIOLÓGICA DE SEMENTES DE BRACHIARIA BRIZANTHA TRATADAS COM FUNGICIDA E INSETICIDA

This study aimed to evaluate the effects of chemical treatment of seeds with fungicide and insecticide on the seed physiological quality of Brachiaria brizantha cultivar MG5. Two experiments with four replicates were carried out in a completely randomized design. In the first experiment, the seeds were treated with the fungicide pyraclostrobin + fipronil + thiophanate-methyl and in the second, with the insecticide thiamethoxam, both at doses of 0, 150, 300, 450, and 600 mL of commercial product (CP)/100 kg of seeds. Physiological characterization was done on the basis of the first germination count, germination (%), emergence (%), emergence speed index, and length and dry mass of shoot and root. The treatment of B. brizantha seeds with the fungicide pyraclostrobin + fipronil + thiophanate-methyl benefits the physiological quality of seeds, improving germination and root development, with no phytotoxic effect up to the dose of 600 mL of CP/100 kg of seeds. The insecticide thiamethoxam has a biostimulating effect on B. brizantha cultivar MG5 up to the dose of 270 mL of CP/100 kg of seeds, but is phytotoxic in larger doses.

Tratamentos para incrementar, acelerar e sincronizar a emergência de plântulas de mucuna-preta

A mucuna-preta e uma leguminosa empregada na recuperacao de solos degradados; no entanto, a dormencia influencia negativamente a germinacao das sementes e o estabelecimento das plântulas. O objetivo foi selecionar tratamentos para eliminar a dormencia de sementes de mucuna-preta e, assim, acelerar e sincronizar a emergencia de plântulas. O experimento foi realizado em delineamento inteiramente casualizado com 10 tratamentos, cada um com quatro repeticoes de 25 sementes. Os tratamentos foram: testemunha (sementes intactas), imersao em agua aquecida a 60 oC, escarificacao mecânica com esmeril eletrico por um segundo na regiao distal da semente e escarificacao com acido sulfurico (H2SO4 98%) por 5; 10; 15; 20; 25; 30 e 35 minutos. As avaliacoes ocorreram por meio do teste de emergencia de plântulas, tempo medio de emergencia, indice de velocidade de emergencia e frequencia relativa de emergencia. A emergencia de plântulas de mucuna-preta e incrementada e o tempo medio de emergencia reduzido por meio da escarificacao na regiao distal da semente e imersao em acido sulfurico por periodos de 5 a 35 minutos. O tratamento acido por 10 a 20 minutos aumenta, acelera e sincroniza a emergencia das plântulas de mucuna-preta, mas o uso de 10 minutos permite reduzir o tempo de contato com o H2SO4.

INITIAL DEVELOPMENT OF AÇAÍ PLANTS UNDER SHADE GRADATION

In order to evaluate the effect of different levels of shading on acai (Euterpe oleracea Mart.) plants development, an experiment was conducted at the nursery of Floresta, Rio Branco, AC. The experiment was arranged in a completely randomized design with six treatments and four replications of 25 plants, set as full sunlight and 18%, 35%, 50%, 70%, and 80% shading. The evaluation occurred 125 days after transplantation and the variables were stem diameter, root length, length of the aerial part, total length, dry matter of root, dry matter of aerial part, and total dry matter. With exception of root length, there was significant difference between treatments for all variables. The production of acai plants should be performed using 40% shading.