Activated charcoal in the control of oxidation and in vitro growth of Dioscorea spp. nodal segments

In vitrooxidationisaproblem forsome herbaceous and woody species and can causedarkening of tissues and consequently death of explantsand plants Therefore, this study aimed to assess the effect of activated charcoal on in vitro yamcultivation, aiming at reducing or eliminating explant oxidation and optimizing the growth of the genotypes Dioscorea alata var.purpurea(Roxb.) A. Pouchet and Dioscorea rotundataPoir. Nodal segments of approximately 1 cm, extracted from plants previously grown in vitro, were introduced into test tubes containing 10 mL of 2GGC culture medium, plus 30 g L-1sucrose, solidified with 2.2 g L-1Phytagel®and pH adjusted to 5.8 before autoclaving, containing activated charcoal doses of 0, 1, 2, 3 and 4 g L-1. Plants were maintained for 90 days in a growth room, with temperature of 27 ± 1ºC, photon flux density of 30 µmol m-2s-1and photoperiod of 16 hours, after which their development variables were evaluated. Activated charcoal, at the concentration of 4 g L-1considerably promoted the best development of plants, and the species D. alatavar.purpureashowed higher means for all variables studied.(AU)

Abscisic acid and in vitro conservation of Manihot wild species

Abscisic acid (ABA) is associated with bud dormancy, leaf abscission, and germplasm growth inhibition in in vitro conservation. We evaluated the effects of ABA in four wild Manihot accessions and one cassava accession (M. esculenta Crantz) to refine in vitro conservation methods for these species. The experiment was performed at the Laboratory for Tissue Culture from Embrapa, Cruz das Almas, Bahia State, Brazil. The statistical design was completely random in a 5 × 5 factorial scheme [(5 ABA dosages (0, 0.25, 0.50, 0.75, and 1 mg L-1) and 5 Manihot species (M. pseudoglaziovii, M. tristis, M. flabellifolia, M. chlorosticta, and M. esculenta)], with 15 replicates. Mini-cuttings of 1 cm were used, each inoculated in 10 mL of modified Murashige and Skoog medium, solidified with Phytagel® (2.4 g L-1) containing the respective ABA dosages. Tubes containing these mini-cuttings were placed in a germplasm conservation room with an irradiance of 30 µmol m-2 s-1, temperature of 22 ± 1°C, and photoperiod of 12 hours. Plant height (cm), the number of living and senescent leaves, shoots, and mini-cuttings (1 cm), and fresh and dry weights of shoots and roots (mg) were evaluated after 150 days. Growth reduction was prominent in M. pseudoglaziovii, M. tristis, and M. flabellifolia during the in vitro conservation period. In the present study, the addition of ABA did not promote the expected reduction in plant growth.(AU)

In vitro conservation of 'Florida Rough' lemon plants / Conservação in vitro de plantas de limoeiro 'Rugoso da Florida'

The establishment of minimum growth conditions is essential for in vitro germplasm conservation. Changes to the basic medium and carbon source concentrations are important factors for reducing plant growth in vitro. This study adjusted a protocol for the in vitro conservation of 'Florida Rough' lemon plants. Microcuttings (approximately 1 cm) from plants that were previously cultivated in vitro were inoculated into test tubes with 10 mL of woody plant medium (WPM) at different concentrations (1/1, 1/2 and 1/4) and supplemented with 0, 12.5, 25 and 50 g.L-1 of sucrose, solidified with 7 g.L-1 agar and adjusted to pH 5.8. The experiment was completely randomized in a 3 x 4 factorial design with 15 replications and was maintained under controlled conditions for 360 days. After this period the plant height in cm (PH), the plant dry mass in g (PDM) and the 21 numbers of green leaves (NGL), senescent leaves (NSL) and microcuttings (NM) were evaluated. The variables that best explained the observed behavior of the 'Florida Rough' lemon plants were NGL and PH, with values of 61.63 and 35.08%, respectively. The original concentration of the WPM with the addition of 25 g. L-1 of sucrose yielded the best 'Florida Rough' lemon plant growth reduction in vitro while maintaining the physiologically health of the plants.

O estabelecimento de condições de crescimento mínimo é fundamental para a conservação in vitro de germoplasma. Alterações nas concentrações do meio básico, na fonte de carbono, são fatores importantes na desaceleração do crescimento de plantas in vitro. Este trabalho teve como objetivo ajustar um protocolo de conservação in vitro de plantas do limoeiro 'Rugoso da Flórida'. Microestacas de plantas previamente cultivadas in vitro, com aproximadamente 1 cm, foram inoculadas em tubos de ensaio contendo 10 mL do meio de cultura WPM em diferentes concentrações (1/1, 1/2 e 1/4), suplementado com 0; 12,5; 25 e 50 g.L-1 de sacarose, solidificado com 7 g.L-1 de ágar e o pH ajustado em 5,8. O experimento foi instalado em delineamento inteiramente casualizado com 15 repetições, em esquema fatorial 3 x 4, e mantido sob condições controladas durante 360 dias. Após este período, foram avaliadas altura de planta em cm (AP), número de folhas verdes (NFV), número de folhas senescentes (NFS), número de microestacas (NM) e massa da planta seca em g (MPS). As variáveis que mais contribuíram para explicar a diferença existente no comportamento das plantas do limoeiro 'Rugoso da Flórida' no meio de cultura WPM foram NFV e AP com 61,63 e 35,08%, respectivamente. O meio de cultura WPM na sua concentração original com a adição de 25 g.L-1 de sacarose promoveu os melhores resultados na redução do crescimento das plantas in vitro do limoeiro 'Rugoso da Flórida', mantendo-as fisiologicamente sadias.

Strategies for vegetative propagation and viral cleaning of a miniature ornamental pineapple hybrid

This study assessed and compared different methods for vegetative propagation of a miniature ornamental pineapple hybrid (ORN-MUT), seeking to determine the best method for production of plantlets, as well as for removal of the PMWaV viral complex from plants cultured in vitro, for production of healthy parent plants. Pineapple wilt is a disease that can cause large economic and is caused by a viral complex called Pineapple mealybug wilt-associated virus (PMWaV). For this, four propagation methods were evaluated (conventional, stem sectioning, micropropagation and etiolation of nodal segments). The time necessary for each method and the number of plants formed were assessed. Stem tips (0.5 mm) were cultured and indexed for three PMWaV types. Conventional propagation produced 17 plantlets per plant in 566 days, stem sectioning produced 2.3 plantlets per stem in 591 days, while the conventional micropropagation technique produced 1,284 plants after four subcultures in 778 days. Stems etiolated for 60 days showed peak production in the second subculture, with 1,224 plants. This method required 883 days to obtain plants with ideal size for transplantation to the field. In turn, stems etiolated for 120 days produced 935 plants at the end of four subcultures, with peak output in the third subculture, in which the plants could be cultivated in the field after 943 days. Conventional micropropagation and etiolation for 60 days were the best methods for production of plantlets of the ORN-MUT hybrid. The results of this work showed that the cultivation of shoot tips is an efficient strategy to remove the PMWaV complex and obtain healthy mother plants and can be a useful tool for other varieties of pineapple.

Strategies for vegetative propagation and viral cleaning of a miniature ornamental pineapple hybrid

This study assessed and compared different methods for vegetative propagation of a miniature ornamental pineapple hybrid (ORN-MUT), seeking to determine the best method for production of plantlets, as well as for removal of the PMWaV viral complex from plants cultured in vitro, for production of healthy parent plants. Pineapple wilt is a disease that can cause large economic and is caused by a viral complex called Pineapple mealybug wilt-associated virus (PMWaV). For this, four propagation methods were evaluated (conventional, stem sectioning, micropropagation and etiolation of nodal segments). The time necessary for each method and the number of plants formed were assessed. Stem tips (0.5 mm) were cultured and indexed for three PMWaV types. Conventional propagation produced 17 plantlets per plant in 566 days, stem sectioning produced 2.3 plantlets per stem in 591 days, while the conventional micropropagation technique produced 1,284 plants after four subcultures in 778 days. Stems etiolated for 60 days showed peak production in the second subculture, with 1,224 plants. This method required 883 days to obtain plants with ideal size for transplantation to the field. In turn, stems etiolated for 120 days produced 935 plants at the end of four subcultures, with peak output in the third subculture, in which the plants could be cultivated in the field after 943 days. Conventional micropropagation and etiolation for 60 days were the best methods for production of plantlets of the ORN-MUT hybrid. The results of this work showed that the cultivation of shoot tips is an efficient strategy to remove the PMWaV complex and obtain healthy mother plants and can be a useful tool for other varieties of pineapple.(AU)

In vitro multiplication of wild Manihot species with different naphthaleneacetic acid and benzylaminopurine concentrations

In vitro multiplication is an important tissue culture technique that is capable of efficiently producing seedlings at any scale. It is a propagation method based on the aseptic culture of small propagules in a suitable culture medium to enable plant regeneration. Multiplication experiments conducted in vitro to set protocols adapted to wild Manihot species have used modified mineral salts and MS vitamins as basic culture medium. Here, 25 treatments based on combinations of the regulators benzylaminopurine (BAP) and naphthaleneacetic acid (NAA) at 0, 0.025, 0.05, 0.075, and 0.1 mg L-1 were used for in vitro multiplication of three genotypes of wild Manihot species (M. violaceae Pohl Müll. Arg., M. pseudoglaziovii Pax & Hoff., and M. flabellifolia Pohl). Plant height and the number of 1 cm minicuttings, number of roots, shoots, green leaves and senescent leaves were recorded 120 days after explant inoculation. M. violaceae Pohl. Müll. Arg. and M. flabellifolia Pohl. presented favorable results with 0.05 and 0.025 mg L-1 NAA, respectively. Culture medium lacking NAA and BAP favored the in vitro growth of M. pseudoglaziovii Pax & Hoff.

Abscisic acid and in vitro conservation of Manihot wild species / Abscisic acid and in vitro conservation of Manihot wild species

Abscisic acid (ABA) is associated with bud dormancy, leaf abscission, and germplasm growth inhibition in in vitro conservation. We evaluated the effects of ABA in four wild Manihot accessions and one cassava accession (M. esculenta Crantz) to refine in vitro conservation methods for these species. The experiment was performed at the Laboratory for Tissue Culture from Embrapa, Cruz das Almas, Bahia State, Brazil. The statistical design was completely random in a 5 × 5 factorial scheme [(5 ABA dosages (0, 0.25, 0.50, 0.75, and 1 mg L-1) and 5 Manihot species (M. pseudoglaziovii, M. tristis, M. flabellifolia, M. chlorosticta, and M. esculenta)], with 15 replicates. Mini-cuttings of 1 cm were used, each inoculated in 10 mL of modified Murashige and Skoog medium, solidified with Phytagel® (2.4 g L-1) containing the respective ABA dosages. Tubes containing these mini-cuttings were placed in a germplasm conservation room with an irradiance of 30 µmol m-2 s-1, temperature of 22 ± 1°C, and photoperiod of 12 hours. Plant height (cm), the number of living and senescent leaves, shoots, and mini-cuttings (1 cm), and fresh and dry weights of shoots and roots (mg) were evaluated after 150 days. Growth reduction was prominent in M. pseudoglaziovii, M. tristis, and M. flabellifolia during the in vitro conservation period. In the present study, the addition of ABA did not promote the expected re

Abscisic acid (ABA) is associated with bud dormancy, leaf abscission, and germplasm growth inhibition in in vitro conservation. We evaluated the effects of ABA in four wild Manihot accessions and one cassava accession (M. esculenta Crantz) to refine in vitro conservation methods for these species. The experiment was performed at the Laboratory for Tissue Culture from Embrapa, Cruz das Almas, Bahia State, Brazil. The statistical design was completely random in a 5 × 5 factorial scheme [(5 ABA dosages (0, 0.25, 0.50, 0.75, and 1 mg L-1) and 5 Manihot species (M. pseudoglaziovii, M. tristis, M. flabellifolia, M. chlorosticta, and M. esculenta)], with 15 replicates. Mini-cuttings of 1 cm were used, each inoculated in 10 mL of modified Murashige and Skoog medium, solidified with Phytagel® (2.4 g L-1) containing the respective ABA dosages. Tubes containing these mini-cuttings were placed in a germplasm conservation room with an irradiance of 30 µmol m-2 s-1, temperature of 22 ± 1°C, and photoperiod of 12 hours. Plant height (cm), the number of living and senescent leaves, shoots, and mini-cuttings (1 cm), and fresh and dry weights of shoots and roots (mg) were evaluated after 150 days. Growth reduction was prominent in M. pseudoglaziovii, M. tristis, and M. flabellifolia during the in vitro conservation period. In the present study, the addition of ABA did not promote the expected re

In vitro multiplication of wild Manihot species with different naphthaleneacetic acid and benzylaminopurine concentrations

In vitro multiplication is an important tissue culture technique that is capable of efficiently producing seedlings at any scale. It is a propagation method based on the aseptic culture of small propagules in a suitable culture medium to enable plant regeneration. Multiplication experiments conducted in vitro to set protocols adapted to wild Manihot species have used modified mineral salts and MS vitamins as basic culture medium. Here, 25 treatments based on combinations of the regulators benzylaminopurine (BAP) and naphthaleneacetic acid (NAA) at 0, 0.025, 0.05, 0.075, and 0.1 mg L-1 were used for in vitro multiplication of three genotypes of wild Manihot species (M. violaceae Pohl Müll. Arg., M. pseudoglaziovii Pax & Hoff., and M. flabellifolia Pohl). Plant height and the number of 1 cm minicuttings, number of roots, shoots, green leaves and senescent leaves were recorded 120 days after explant inoculation. M. violaceae Pohl. Müll. Arg. and M. flabellifolia Pohl. presented favorable results with 0.05 and 0.025 mg L-1 NAA, respectively. Culture medium lacking NAA and BAP favored the in vitro growth of M. pseudoglaziovii Pax & Hoff.(AU)

Physicochemical and sensory properties of papaya fruits of elite lines and hybrids / Características físico-químicas e sensoriais de frutos de híbridos e linhagens elites de mamoeiro

This study aimed to evaluate papaya elite lines and hybrids as to fruit physicochemical and sensory characteristics, thus identifying the most promising ones for the market. Fruits from improved genotypes of the Solo group (CMF H10.60, CMF L78, and UC 14) and Formosa group (CMF L10, UC 10, and UC 12) were evaluated, and the commercial cultivars Golden and Tainung nº 1 were used as controls. The following physical and physicochemical evaluations were performed: fruit length and diameter, fruit inner cavity diameter, fruit weight, fruit and pulp firmness, soluble solids, pH, titratable acidity, Ratio (soluble solids and titratable acidit relation), and firmness of peeled and unpeeled ripe fruits. Sensory tests were performed with 50 papaya consumers. In general, the improved genotypes of the Solo and Formosa groups showed similar physical and physicochemical characteristics to the Golden and Tainung n 1 controls. The CMF L78 line of the Solo group and the UC10 hybrid of the Formosa group showed similar fruit firmness and ratio characteristics compared to both commercial cultivars. The three new genotypes in the Solo group showed superior sensory characteristics to the commercial cultivar Golden. The internal preference mapping of this group revealed a higher preference for the genotypes UC 14 and CMF L78, for having fruits with more intense color, stronger flavor, and firmer texture than the others. In the Formosa group, the UC 10 genotype outperformed the cultivar Tainung nº 1, with a global acceptance percentage of 96.15%, due to a more intense aroma, color, and flavor. The CMF L78 line of the Solo group and the UC 10 hybrid of the Formosa group have excellent physicochemical and sensory characteristics and are therefore promising alternatives to replace both commercial cultivars (Golden and Tainung nº 1).

O objetivo deste trabalho foi avaliar linhagens e híbridos elites de mamoeiro quanto às características físico-químicas e sensoriais de frutos, visando identificar os mais promissores para o mercado. Foram avaliados frutos de genótipos melhorados do grupo Solo (CMF H10.60, CMF L78, UC 14) e do grupo Formosa (CMF L10, UC 10, UC 12), e como testemunhas as variedades comerciais Golden e Tainung nº 1. Foram realizadas as seguintes avaliações físicas e físico-químicas: comprimento e diâmetro do fruto, diâmetro da cavidade interna dos frutos, peso do fruto, firmeza do fruto e da polpa, sólidos solúveis, pH, acidez titulável Ratio (razão entre sólidos solúveis e acidez titulável) e firmeza dos frutos maduros com casca e sem a casca. Os testes sensoriais foram realizados com 50 consumidores de mamão. De uma forma geral, os genótipos melhorados do grupo Solo e Formosa apresentaram características físicas e físico-químicas semelhantes às testemunhas Golden e Tainung nº1. A linhagem CMF L78, do grupo Solo, e o híbrido UC10, do grupo Formosa, apresentaram características de firmeza de fruto e Ratio semelhantes às cultivares comerciais Golden e Tainung nº1. Em relação às características sensoriais dos genótipos do grupo Solo, os três novos genótipos superaram a cultivar comercial Golden. O mapa de preferência interno desse grupo revelou uma maior preferência para os genótipos UC 14 e CMF L78, que foram considerados frutos com cor mais intensa, sabor mais forte e textura mais firme que os demais. No grupo Formosa, o genótipo UC 10 superou a cultivar Tainung n°1, com percentual de aceitação global 96,15% e foi considerado com aroma, cor e sabor mais intensos. A linhagem CMF L78, do grupo Solo, e o híbrido UC 10, do grupo Formosa, apresentam excelentes características físico-químicas e sensoriais e, portanto, são alternativas promissoras para substituir as cultivares comerciais Golden e Tainung n°1.

Physicochemical and sensory properties of papaya fruits of elite lines and hybrids / Características físico-químicas e sensoriais de frutos de híbridos e linhagens elites de mamoeiro

This study aimed to evaluate papaya elite lines and hybrids as to fruit physicochemical and sensory characteristics, thus identifying the most promising ones for the market. Fruits from improved genotypes of the Solo group (CMF H10.60, CMF L78, and UC 14) and Formosa group (CMF L10, UC 10, and UC 12) were evaluated, and the commercial cultivars Golden and Tainung nº 1 were used as controls. The following physical and physicochemical evaluations were performed: fruit length and diameter, fruit inner cavity diameter, fruit weight, fruit and pulp firmness, soluble solids, pH, titratable acidity, Ratio (soluble solids and titratable acidit relation), and firmness of peeled and unpeeled ripe fruits. Sensory tests were performed with 50 papaya consumers. In general, the improved genotypes of the Solo and Formosa groups showed similar physical and physicochemical characteristics to the Golden and Tainung n 1 controls. The CMF L78 line of the Solo group and the UC10 hybrid of the Formosa group showed similar fruit firmness and ratio characteristics compared to both commercial cultivars. The three new genotypes in the Solo group showed superior sensory characteristics to the commercial cultivar Golden. The internal preference mapping of this group revealed a higher preference for the genotypes UC 14 and CMF L78, for having fruits with more intense color, stronger flavor, and firmer texture than the others. In the Formosa group, the UC 10 genotype outperformed the cultivar Tainung nº 1, with a global acceptance percentage of 96.15%, due to a more intense aroma, color, and flavor. The CMF L78 line of the Solo group and the UC 10 hybrid of the Formosa group have excellent physicochemical and sensory characteristics and are therefore promising alternatives to replace both commercial cultivars (Golden and Tainung nº 1).(AU)

O objetivo deste trabalho foi avaliar linhagens e híbridos elites de mamoeiro quanto às características físico-químicas e sensoriais de frutos, visando identificar os mais promissores para o mercado. Foram avaliados frutos de genótipos melhorados do grupo Solo (CMF H10.60, CMF L78, UC 14) e do grupo Formosa (CMF L10, UC 10, UC 12), e como testemunhas as variedades comerciais Golden e Tainung nº 1. Foram realizadas as seguintes avaliações físicas e físico-químicas: comprimento e diâmetro do fruto, diâmetro da cavidade interna dos frutos, peso do fruto, firmeza do fruto e da polpa, sólidos solúveis, pH, acidez titulável Ratio (razão entre sólidos solúveis e acidez titulável) e firmeza dos frutos maduros com casca e sem a casca. Os testes sensoriais foram realizados com 50 consumidores de mamão. De uma forma geral, os genótipos melhorados do grupo Solo e Formosa apresentaram características físicas e físico-químicas semelhantes às testemunhas Golden e Tainung nº1. A linhagem CMF L78, do grupo Solo, e o híbrido UC10, do grupo Formosa, apresentaram características de firmeza de fruto e Ratio semelhantes às cultivares comerciais Golden e Tainung nº1. Em relação às características sensoriais dos genótipos do grupo Solo, os três novos genótipos superaram a cultivar comercial Golden. O mapa de preferência interno desse grupo revelou uma maior preferência para os genótipos UC 14 e CMF L78, que foram considerados frutos com cor mais intensa, sabor mais forte e textura mais firme que os demais. No grupo Formosa, o genótipo UC 10 superou a cultivar Tainung n°1, com percentual de aceitação global 96,15% e foi considerado com aroma, cor e sabor mais intensos. A linhagem CMF L78, do grupo Solo, e o híbrido UC 10, do grupo Formosa, apresentam excelentes características físico-químicas e sensoriais e, portanto, são alternativas promissoras para substituir as cultivares comerciais Golden e Tainung n°1.(AU)

Aqueous plant extracts in the control of Bidens pilosa L / Extratos aquosos vegetais no controle de Bidens pilosa L

Secondary compounds have allelopathic action on germination and growth, and initial development of seedlings and beggar tick can have its germination and growth affected by the action of allelopathic extracts. Thus, this work aimed to evaluate the allelopathic potential of Brachiaria (Brachiaria brizantha), sunflower (Helianthus annuus) and sorghum extracts (Sorghum bicolor) on germination and initial growth of beggar ticks (Bidens pilosa). For this, an experiment was conducted in a completely randomized design with four treatments and six replicates and brachiaria, sunflower and sorghum extracts and control (distilled water) treatments. Extracts were obtained using 200 g of plant material and 1,000 mL of distilled water. Seeds were distributed in gerbox containing two sheets of germitest paper moistened with treatments and taken to germination chamber. Germination was daily monitored, and ten days after, initial growth was evaluated. Extracts did not reduce germination. However, they caused increase in germination time, mainly by brachiaria extract. Seedlings submitted to brachiaria and sorghum extracts showed lower growth. Brachiaria and sorghum extracts showed no action on germination, but controlled the initial growth of beggar tick, being potential natural herbicides.(AU)

Compostos secundários têm ação alelopática sobre a germinação, crescimento e desenvolvimento inicial de plântulas, e a Bidens pilosa pode ter sua germinação e crescimento afetados pela ação dos extratos alelopáticos. Nesse sentido, objetivou-se avaliar o potencial alelopático de extratos de braquiária (Brachiaria brizantha), girassol (Helianthus annus) e sorgo (Sorghum bicolor) na germinabilidade e no crescimento inicial de picão-preto (Bidens pilosa). Para isso foi instalado um experimento no delineamento inteiramente casualizado, com quatro tratamentos e seis repetições, sendo eles extrato de braquiária, girassol, sorgo e o controle (água destilada). Os extratos foram obtidos utilizando 200 g de material vegetal fresco para 1.000 mL de água destilada. As sementes foram distribuídas em caixa gerbox contendo duas folhas de papel germitest umedecidas com os tratamentos e levadas para a câmara de germinação. Foi acompanhada diariamente a germinação e, após 10 dias, foi avaliado o crescimento inicial. Os extratos não causaram prejuízos à germinação, porém, provocaram demora em seu tempo de eclosão, sendo o extrato de braquiária o mais prejudicial. As plântulas submetidas aos extratos de braquiária e sorgo apresentaram menor crescimento. Os extratos de braquiária e sorgo não apresentaram ação sobre a porcentagem de germinação das sementes de picão-preto, mas controlaram o crescimento inicial das plântulas e podem ser indicados para possíveis herbicidas naturais.(AU)

Aqueous plant extracts in the control of Bidens pilosa L / Extratos aquosos vegetais no controle de Bidens pilosa L

Secondary compounds have allelopathic action on germination and growth, and initial development of seedlings and beggar tick can have its germination and growth affected by the action of allelopathic extracts. Thus, this work aimed to evaluate the allelopathic potential of Brachiaria (Brachiaria brizantha), sunflower (Helianthus annuus) and sorghum extracts (Sorghum bicolor) on germination and initial growth of beggar ticks (Bidens pilosa). For this, an experiment was conducted in a completely randomized design with four treatments and six replicates and brachiaria, sunflower and sorghum extracts and control (distilled water) treatments. Extracts were obtained using 200 g of plant material and 1,000 mL of distilled water. Seeds were distributed in gerbox containing two sheets of germitest paper moistened with treatments and taken to germination chamber. Germination was daily monitored, and ten days after, initial growth was evaluated. Extracts did not reduce germination. However, they caused increase in germination time, mainly by brachiaria extract. Seedlings submitted to brachiaria and sorghum extracts showed lower growth. Brachiaria and sorghum extracts showed no action on germination, but controlled the initial growth of beggar tick, being potential natural herbicides.(AU)

Compostos secundários têm ação alelopática sobre a germinação, crescimento e desenvolvimento inicial de plântulas, e a Bidens pilosa pode ter sua germinação e crescimento afetados pela ação dos extratos alelopáticos. Nesse sentido, objetivou-se avaliar o potencial alelopático de extratos de braquiária (Brachiaria brizantha), girassol (Helianthus annus) e sorgo (Sorghum bicolor) na germinabilidade e no crescimento inicial de picão-preto (Bidens pilosa). Para isso foi instalado um experimento no delineamento inteiramente casualizado, com quatro tratamentos e seis repetições, sendo eles extrato de braquiária, girassol, sorgo e o controle (água destilada). Os extratos foram obtidos utilizando 200 g de material vegetal fresco para 1.000 mL de água destilada. As sementes foram distribuídas em caixa gerbox contendo duas folhas de papel germitest umedecidas com os tratamentos e levadas para a câmara de germinação. Foi acompanhada diariamente a germinação e, após 10 dias, foi avaliado o crescimento inicial. Os extratos não causaram prejuízos à germinação, porém, provocaram demora em seu tempo de eclosão, sendo o extrato de braquiária o mais prejudicial. As plântulas submetidas aos extratos de braquiária e sorgo apresentaram menor crescimento. Os extratos de braquiária e sorgo não apresentaram ação sobre a porcentagem de germinação das sementes de picão-preto, mas controlaram o crescimento inicial das plântulas e podem ser indicados para possíveis herbicidas naturais.(AU)

Evaluation of feeding rates in the production of Litopenaeus vannamei shrimp using artificial substrates / Avaliação das taxas de arraçoamento na produção do camarão Litopenaeus vannamei utilizando substratos artificiais

The objective of this study was to evaluate the the influence of feeding rate and different artificial substrates on both the water quality and growth performance of Litopenaeus vannamei shrimp. The experimental design was randomized blocks with five treatments and four replicates, with a density of 30 shrimp m-2 and mean weight of 2.8 g. The experiment lasted 49 days, and during this period, artificial substrates did not influence the water quality. The increase in the feeding rate influenced the dissolved oxygen of treatments. The final average weight, average final length, final biomass, productivity, and feed conversion rate showed significant differences (p > 0.05). The best food conversion factor was provided by the treatment with a feeding rate of 2%. The treatment with a feeding rate of 4% of biomass showed the best growth performance, except for the feed conversion rate. Results showed that for the percentage of 25% of the area of artificial substrates, there is an optimum feeding rate of between 5.13% and 5.54% of shrimp biomass, resulting in maximum production.

O objetivo deste trabalho foi avaliar a taxa de arraçoamento, sobre a influência dos substratos artificiais na qualidade da água e índices zootécnicos do camarão Litopenaeus vannamei. O delineamento experimental adotado foi em blocos casualizados com cinco tratamentos e quatro repetições, com densidade de 30 camarões/m2, e peso médio de 2,8 g, o experimento teve duração de 49 dias, durante este período os substratos artificiais não influenciaram na qualidade da água. O aumento da taxa de arraçoamento influenciou no oxigênio dissolvido dos tratamentos. O peso médio final, comprimento médio final, biomassa final, produtividade e fator de conversão alimentar apresentaram diferenças significativas (p>0,05). O melhor fator de conversão alimentar foi proporcionado pelo tratamento com taxa de arraçoamento de 2%. O tratamento com arraçoamento de 4% da biomassa apresentou os melhores índices zootécnicos, com exceção do fator de conversão alimentar. Os resultados mostram que para o percentual de 25% de área de substratos artificiais existe um ótimo percentual de arraçoamento que está entre 5,13% e 5,54% da biomassa dos camarões resultando na maximização da produção.

Evaluation of feeding rates in the production of Litopenaeus vannamei shrimp using artificial substrates / Avaliação das taxas de arraçoamento na produção do camarão Litopenaeus vannamei utilizando substratos artificiais

The objective of this study was to evaluate the the influence of feeding rate and different artificial substrates on both the water quality and growth performance of Litopenaeus vannamei shrimp. The experimental design was randomized blocks with five treatments and four replicates, with a density of 30 shrimp m-2 and mean weight of 2.8 g. The experiment lasted 49 days, and during this period, artificial substrates did not influence the water quality. The increase in the feeding rate influenced the dissolved oxygen of treatments. The final average weight, average final length, final biomass, productivity, and feed conversion rate showed significant differences (p > 0.05). The best food conversion factor was provided by the treatment with a feeding rate of 2%. The treatment with a feeding rate of 4% of biomass showed the best growth performance, except for the feed conversion rate. Results showed that for the percentage of 25% of the area of artificial substrates, there is an optimum feeding rate of between 5.13% and 5.54% of shrimp biomass, resulting in maximum production.(AU)

O objetivo deste trabalho foi avaliar a taxa de arraçoamento, sobre a influência dos substratos artificiais na qualidade da água e índices zootécnicos do camarão Litopenaeus vannamei. O delineamento experimental adotado foi em blocos casualizados com cinco tratamentos e quatro repetições, com densidade de 30 camarões/m2, e peso médio de 2,8 g, o experimento teve duração de 49 dias, durante este período os substratos artificiais não influenciaram na qualidade da água. O aumento da taxa de arraçoamento influenciou no oxigênio dissolvido dos tratamentos. O peso médio final, comprimento médio final, biomassa final, produtividade e fator de conversão alimentar apresentaram diferenças significativas (p>0,05). O melhor fator de conversão alimentar foi proporcionado pelo tratamento com taxa de arraçoamento de 2%. O tratamento com arraçoamento de 4% da biomassa apresentou os melhores índices zootécnicos, com exceção do fator de conversão alimentar. Os resultados mostram que para o percentual de 25% de área de substratos artificiais existe um ótimo percentual de arraçoamento que está entre 5,13% e 5,54% da biomassa dos camarões resultando na maximização da produção.(AU)

Vigor and mortality of citrus progenies with potential use as rootstocks / 10.1590/1678-992x-2016-0455

Rootstocks influence certain characteristics of the scion, such as vigor, fruit yield and quality, and tolerance to biotic and abiotic factors. In conventional citrus breeding programs, hybridization is the main method used for obtaining rootstock varieties. Between Sept and Oct 2006, controlled pollinations were carried out resulting in nine progenies, totaling 461 hybrid seedlings. The female parents were the ‘Santa Cruz Rangpur’ lime (SCRL) and the ‘Sunki of Florida’ mandarin (SFM), while the male parents, in addition to this mandarin, were the ‘Indio’ and ‘Riverside’ citrandarins, the ‘Thomasville’ citrangequat (THOM), the ‘Swingle’ citrumelo, the ‘Argentina’ citrange (AGC) and the ‘Benecke’ trifoliate orange (BKTO). Fruit setting rates of these crosses were measured and the hybrids generated were planted in the field in 2008 and evaluated from 2010 to 2014, for the variables of plant mortality, visual vigor, plant height and trunk diameter. The descriptive statistics mean, variation range, coefficient of variation and Pearson skewness coefficient were calculated. Data were submitted to analysis of variance and the means of the treatments were grouped by the Scott-Knott test, both at 5 % significance. The progenies, having the ‘Sunki’ mandarin as the female parent, presented higher fruit setting rates and lower plant mortality rates than those obtained from the female parent ‘Rangpur’ lime, while zero plant mortality was observed in the SFM × BKTO cross. The crosses SCRL × SFM, SFM × BKTO, SFM × AGC and SFM × THOM have the potential to generate vigorous hybrids, resulting in rootstock varieties adapted to the landscape unit of Coastal Tableland.

Evaluation of the micropropagation potential of curauá pineapple hybrids for fiber production / Avaliação do potencial de micropropagação de híbridos do abacaxi curauá para a produção de fibras

Plant fiber is a renewable and biodegradable material that can be used effectively to reinforce various composites. Pineapple hybrids selected for their fiber quality are in the phase of agronomic validation in Brazil by the Embrapa Cassava and Fruits research unit. The selection of a hybrid for large-scale fiber production depends on obtaining a large number of seedlings. This study evaluated the morphogenetic response and propagation potential of eight hybrids of Ananas comosus var. erectifolius, for the purpose of producing high-quality seedlings on a large scale. Stem and crown buds were reduced and placed in MS nutritive medium supplemented with BAP at 0.5 mg L-1, NAA at 0.01 mg L-1 and Phytagel® at 2.5 g L-1. After 45 days, the number of oxidized, contaminated and surviving buds was determined. Swollen buds and plantlets were transferred to a multiplication medium containing MS sucrose, salts and vitamins. The propagation potential was evaluated based on the geometric growth rate among sub-cultures. The FIB-NEG hybrid presented the best results for the establishment phase (40.28%). The best propagative potential was obtained from crown buds with the highest values for FIB-EST (3.93), FIB-MIN (3.91) and FIB-BOY (3.91) hybrids.

A fibra vegetal é uma fonte renovável, biodegradável e de excelente desempenho como reforço em compósitos variados. Híbridos selecionados pela qualidade de suas fibras estão em fase de validação agronômica na Embrapa Mandioca e Fruticultura e sua adoção para produção de fibra em larga escala depende de um elevado número de mudas. Este trabalho teve como objetivo avaliar a resposta morfogenética e o potencial propagativo de oito híbridos de Ananas comosus var. erectifolius, com a finalidade de produzir mudas de qualidade em larga escala. Gemas do caule e coroa foram reduzidas, introduzidas em meio nutritivo MS suplementado com BAP a 0,5 mg L-1, ANA a 0,01 mg L-1 e Phytagel® a 2,5 g L-1. Aos 45 dias foram avaliados o número de gemas oxidadas, contaminadas e sobreviventes. Gemas intumescidas e plantas formadas foram transferidas para o meio de multiplicação contendo sacarose, sais e vitaminas MS. Avaliou-se o potencial propagativo a partir de uma taxa de crescimento geométrico entre subcultivos. O híbrido FIB-NEG (40.28%) apresentou os melhores resultados em porcentagem para a fase de estabelecimento. O melhor potencial propagativo foi obtido a partir de gemas de coroa, com os valores mais elevados registrados para os híbridos FIB-EST (3.93), FIB-MIN (3.91) e FIB-BOY (3.91).

Vigor and mortality of citrus progenies with potential use as rootstocks / 10.1590/1678-992x-2016-0455

Rootstocks influence certain characteristics of the scion, such as vigor, fruit yield and quality, and tolerance to biotic and abiotic factors. In conventional citrus breeding programs, hybridization is the main method used for obtaining rootstock varieties. Between Sept and Oct 2006, controlled pollinations were carried out resulting in nine progenies, totaling 461 hybrid seedlings. The female parents were the ‘Santa Cruz Rangpur lime (SCRL) and the ‘Sunki of Florida mandarin (SFM), while the male parents, in addition to this mandarin, were the ‘Indio and ‘Riverside citrandarins, the ‘Thomasville citrangequat (THOM), the ‘Swingle citrumelo, the ‘Argentina citrange (AGC) and the ‘Benecke trifoliate orange (BKTO). Fruit setting rates of these crosses were measured and the hybrids generated were planted in the field in 2008 and evaluated from 2010 to 2014, for the variables of plant mortality, visual vigor, plant height and trunk diameter. The descriptive statistics mean, variation range, coefficient of variation and Pearson skewness coefficient were calculated. Data were submitted to analysis of variance and the means of the treatments were grouped by the Scott-Knott test, both at 5 % significance. The progenies, having the ‘Sunki mandarin as the female parent, presented higher fruit setting rates and lower plant mortality rates than those obtained from the female parent ‘Rangpur lime, while zero plant mortality was observed in the SFM × BKTO cross. The crosses SCRL × SFM, SFM × BKTO, SFM × AGC and SFM × THOM have the potential to generate vigorous hybrids, resulting in rootstock varieties adapted to the landscape unit of Coastal Tableland.(AU)

Evaluation of the micropropagation potential of curauá pineapple hybrids for fiber production / Avaliação do potencial de micropropagação de híbridos do abacaxi curauá para a produção de fibras

Plant fiber is a renewable and biodegradable material that can be used effectively to reinforce various composites. Pineapple hybrids selected for their fiber quality are in the phase of agronomic validation in Brazil by the Embrapa Cassava and Fruits research unit. The selection of a hybrid for large-scale fiber production depends on obtaining a large number of seedlings. This study evaluated the morphogenetic response and propagation potential of eight hybrids of Ananas comosus var. erectifolius, for the purpose of producing high-quality seedlings on a large scale. Stem and crown buds were reduced and placed in MS nutritive medium supplemented with BAP at 0.5 mg L-1, NAA at 0.01 mg L-1 and Phytagel® at 2.5 g L-1. After 45 days, the number of oxidized, contaminated and surviving buds was determined. Swollen buds and plantlets were transferred to a multiplication medium containing MS sucrose, salts and vitamins. The propagation potential was evaluated based on the geometric growth rate among sub-cultures. The FIB-NEG hybrid presented the best results for the establishment phase (40.28%). The best propagative potential was obtained from crown buds with the highest values for FIB-EST (3.93), FIB-MIN (3.91) and FIB-BOY (3.91) hybrids.(AU)

A fibra vegetal é uma fonte renovável, biodegradável e de excelente desempenho como reforço em compósitos variados. Híbridos selecionados pela qualidade de suas fibras estão em fase de validação agronômica na Embrapa Mandioca e Fruticultura e sua adoção para produção de fibra em larga escala depende de um elevado número de mudas. Este trabalho teve como objetivo avaliar a resposta morfogenética e o potencial propagativo de oito híbridos de Ananas comosus var. erectifolius, com a finalidade de produzir mudas de qualidade em larga escala. Gemas do caule e coroa foram reduzidas, introduzidas em meio nutritivo MS suplementado com BAP a 0,5 mg L-1, ANA a 0,01 mg L-1 e Phytagel® a 2,5 g L-1. Aos 45 dias foram avaliados o número de gemas oxidadas, contaminadas e sobreviventes. Gemas intumescidas e plantas formadas foram transferidas para o meio de multiplicação contendo sacarose, sais e vitaminas MS. Avaliou-se o potencial propagativo a partir de uma taxa de crescimento geométrico entre subcultivos. O híbrido FIB-NEG (40.28%) apresentou os melhores resultados em porcentagem para a fase de estabelecimento. O melhor potencial propagativo foi obtido a partir de gemas de coroa, com os valores mais elevados registrados para os híbridos FIB-EST (3.93), FIB-MIN (3.91) e FIB-BOY (3.91).(AU)

Correlations and track analysis for morphoagronomic descriptors in pedigree and parental lines of castor bean / Correlações e análise de trilha para descritores morfoagronômicos em linhagens e parentais de mamoneira

As castor bean (Ricinus communis L.) reveals immense adaptability to various ecological conditions and due to its socioeconomic significance, new studies have emerged primarily to develop more productive cultivars to suit different regions in Brazil. This study aimed to confirmthe correlations and direct and indirect effects of the morphoagronomic descriptors on castor bean productivity, employing correlation studies and track analysis. Between 2014 and 2015, experiments utilizing the randomized block design were performed, with four replications, which included 208 treatments involving pedigree and parental lines of castor bean, drawn from the germplasm bank of the Universidade Federal do Recôncavo da Bahia. Variables in the correlation analysis included primary racemic insertion, stem diameter, number of stem internodes, plant flowering, plant height, racemic length, number of fruits per raceme, fruit weight per raceme, seed yield per fruit and productivity. Correlations among the variables analyzed were imposed, via track analysis, on the direct and indirect influences of the morphoagronomic descriptors on productivity. The most direct and positively influential descriptors included fruit weight per raceme and number of seeds per raceme; the most direct albeit negatively influential descriptors are the number of internodes on the stem and flowering. Therefore, lines with less number ofinternodes and requiring fewer days to bloom are more highly productive. These descriptors can thus effectively identify the productive lines.

A capacidade da mamoneira (Ricinus communis L.) em adaptar-se a diferentes condições ecológicas e a sua importância socioeconômica impulsionou novas pesquisas com a espécie, visando o desenvolvimento de cultivares mais produtivas para as diferentes regiões do país. Assim, este trabalho objetivou verificar as correlações e o efeito direto e indireto de descritores morfoagronômicos sobre a produtividade de mamoneiras, por meio do estudo de correlação e análise de trilha. O experimento foi conduzido no período de 2014 a 2015, em delineamento de blocos casualizados, com quatro repetições. Foram 208 tratamentos compostos por linhagens e parentais de mamoneira do Banco de germoplasma da Universidade Federal do Recôncavo da Bahia. As variáveis utilizadas para a análise de correlação foram: inserção do racemo primário, diâmetro do caule, número de internódios do caule, florescimento da planta, estatura da planta, comprimento do racemo, número de frutos por racemo, peso dos frutos por racemo, rendimento de sementes por fruto e produtividade. As correlações entre as variáveis analisadas foram desdobradas pela análise de trilha, em efeitos diretos e indiretos dos descritores morfoagronômico sobre a produtividade. Os descritores que exercem maiores efeitos diretos no sentido positivo sobre a produtividade são o peso de frutos por racemo e número de sementes por racemo.Os descritores com maior efeito direto no sentido negativo são o número de internódios do caule e o florescimento, indicando que as linhagens com menor número de internódios e que levam menos dias para florescer são mais produtivas. Com isso, estes descritores podem ser eficientes na identificação de linhagens produtivas.

Correlations and track analysis for morphoagronomic descriptors in pedigree and parental lines of castor bean / Correlações e análise de trilha para descritores morfoagronômicos em linhagens e parentais de mamoneira

As castor bean (Ricinus communis L.) reveals immense adaptability to various ecological conditions and due to its socioeconomic significance, new studies have emerged primarily to develop more productive cultivars to suit different regions in Brazil. This study aimed to confirmthe correlations and direct and indirect effects of the morphoagronomic descriptors on castor bean productivity, employing correlation studies and track analysis. Between 2014 and 2015, experiments utilizing the randomized block design were performed, with four replications, which included 208 treatments involving pedigree and parental lines of castor bean, drawn from the germplasm bank of the Universidade Federal do Recôncavo da Bahia. Variables in the correlation analysis included primary racemic insertion, stem diameter, number of stem internodes, plant flowering, plant height, racemic length, number of fruits per raceme, fruit weight per raceme, seed yield per fruit and productivity. Correlations among the variables analyzed were imposed, via track analysis, on the direct and indirect influences of the morphoagronomic descriptors on productivity. The most direct and positively influential descriptors included fruit weight per raceme and number of seeds per raceme; the most direct albeit negatively influential descriptors are the number of internodes on the stem and flowering. Therefore, lines with less number ofinternodes and requiring fewer days to bloom are more highly productive. These descriptors can thus effectively identify the productive lines.(AU)

A capacidade da mamoneira (Ricinus communis L.) em adaptar-se a diferentes condições ecológicas e a sua importância socioeconômica impulsionou novas pesquisas com a espécie, visando o desenvolvimento de cultivares mais produtivas para as diferentes regiões do país. Assim, este trabalho objetivou verificar as correlações e o efeito direto e indireto de descritores morfoagronômicos sobre a produtividade de mamoneiras, por meio do estudo de correlação e análise de trilha. O experimento foi conduzido no período de 2014 a 2015, em delineamento de blocos casualizados, com quatro repetições. Foram 208 tratamentos compostos por linhagens e parentais de mamoneira do Banco de germoplasma da Universidade Federal do Recôncavo da Bahia. As variáveis utilizadas para a análise de correlação foram: inserção do racemo primário, diâmetro do caule, número de internódios do caule, florescimento da planta, estatura da planta, comprimento do racemo, número de frutos por racemo, peso dos frutos por racemo, rendimento de sementes por fruto e produtividade. As correlações entre as variáveis analisadas foram desdobradas pela análise de trilha, em efeitos diretos e indiretos dos descritores morfoagronômico sobre a produtividade. Os descritores que exercem maiores efeitos diretos no sentido positivo sobre a produtividade são o peso de frutos por racemo e número de sementes por racemo.Os descritores com maior efeito direto no sentido negativo são o número de internódios do caule e o florescimento, indicando que as linhagens com menor número de internódios e que levam menos dias para florescer são mais produtivas. Com isso, estes descritores podem ser eficientes na identificação de linhagens produtivas.(AU)