Produção e tecnologia de sementes forrageiras

O presente trabalho apresenta as atividades desenvolvidas durante o Estágio Curricular Obrigatório, realizado no Instituto Nacional de Investigação Agropecuária - INIA/Uruguai no período de 08 de janeiro a 06 de março de 2018, totalizando 320 horas, tendo como objetivo o acompanhamento e realização de atividades referentes ao manejo, produção, beneficiamento e armazenamento de sementes forrageiras

Determinação do vigor de sementes de arroz através do processamento de imagens de plântulas

The aim of this paper was to verify the viability of digital image processing in the measurement of rice seedling and its potential use as seed vigor test. The experiment took place at the Laboratório Didático de Análise de Sementes, located in Capão do Leão (RS), using seeds of eight rice cultivars: Irga 424, Puitá Inta CL, BRS Esmeralda, SCS 116, Guri Inta CL, BRS Pampa, BRSGO Serra Dourada and Olimar. An image processing system (IPS) was used to measure length and area of shoot and root as an index of seed vigor in rice seeds. The experiment design was completely randomized with five replications. The evaluated variables were root and shoot length in graded ruler and by image, root and shoot area, and field emergence. Results obtained with the IPS were correlated with other quality tests though the Pearson tests. Determination of shoot length and leaf area of the seedlings obtained through IPS is effective for assessing the vigor of rice seeds.O objetivo neste trabalho foi verificar a viabilidade do processamento digital de imagens na mensuração de plântulas de arroz e sua potencial utilização como teste de vigor em sementes. O experimento foi realizado no Laboratório Didático de Análise de Sementes, localizado no Capão do Leão (RS), utilizando sementes de oito cultivares de arroz: Irga 424, Puitá Inta CL, BRS Esmeralda, SCS 116, Guri Inta CL, BRS Pampa, BRSGO Serra Dourada e Olimar. Uma ferramenta de processamento de imagens (FPI) foi utilizada para mensurar o comprimento e a área da parte aérea e de raízes de plântulas de arroz de modo a classificar as sementes em níveis de vigor. O delineamento experimental foi inteiramente casualizado com cinco repetições. As variáveis avaliadas foram comprimento de raiz e parte aérea em régua graduada e pela imagem, área de raiz e parte aérea e emergência a campo. Os resultados obtidos com o FPI foram correlacionados com outros testes de qualidade por correlação de Pearson. A determinação do comprimento de parte aérea e área foliar de plântulas obtidos através do FPI é efetivo para avaliar o vigor de sementes de arroz

Produção de forragem de híbridos tetraploides de grama forquilha

In Southern Brazil, much of the livestock activity is developed in native grasslands. Studies about forage traits, frost tolerance and nutritional value of native forage species there has been increasing with better results of productive efficiency (animal gain). The objective of this work was to evaluate forage yieldof forty-five intraspecific hybrids of segregating progenies of bahiagrass (Paspalum notatumFlügge) from agronomic analyses under greenhouse conditions and determine the reproduction mode of selected hybrids. The hybrids had great variability in all agronomic characteristics measured. The plants with the highest total dry mass production were 17PN10P3 and 17PN29P1 (sexualreproduction), 17PN10P5, 17PN16P3 and 17PN28P4 (apomicticreproduction). The high correlation of the total dry mass with tillers numberand with the root dry mass demonstrate that the hybrids can be used as forage and also to reduce the effects of soil erosion in degraded areas. The evaluations of agronomic characteristics and the determinationof the mode of reproduction of the selected hybrids allowed the identification of promising genetic materials for forage yield and to soil cover, selecting them for additional stages in the breeding program.No sul do Brasil, boa parte da atividade pecuária é desenvolvida em pastagens nativas. Estudos sobre caraterísticas agronômicas, tolerância ao frio e valor nutritivo das espécies forrageiras nativas têm aumentado, e melhores resultados de eficiência produtiva (ganho animal) são alcançados. O objetivo deste trabalho foi avaliar a produção de forragem de 45 híbridos intraespecíficos de progênies segregantes de grama-forquilha (Paspalum notatumFlügge), através de análises conduzidas em casa de vegetação e determinar o modo de reprodução dos híbridos selecionados. Os híbridos tiveram grande variabilidade para as características analisadas. As plantas com a mais alta produção total de matéria seca foram 17PN10P3 e 17PN29P1 (reprodução sexual), 17PN10P5, 17PN16P3 e 17PN28P4 (reprodução apomítica). A alta correlação da matéria seca total com o número de perfilhos e com a massa seca total das raízes indica que as plantas híbridas podem ser usadas como forrageiras e para recuperação de áreas degradadas, reduzindo os efeitos da erosão do solo. As avaliações das características agronômicas e adeterminação do modo de reprodução dos híbridos selecionados permitem a identificação de materiais genéticos promissores para produção de forragem e para coberturade solo, selecionando-os para as próximas fases do programa de melhoramento

Root exudation of oxalic acid in Lotus corniculatus in response to aluminum toxicity

The objective of this research was to identify the existence of root exudation of organic acid in Lotus corniculatus germplasms subjected to toxic aluminum (Al) levels and investigate the effect of this mechanism on the Al content in the root tissue and in morphological parameters of plant development. Two experiments were performed in nutrient solution to evaluate the Al accumulation and exudation of organic acids, using cultivars INIA Draco and São Gabriel and genotypes UFRGS and UF-T2. The plants were cultivated in Al-free solution, which was applied on the 45th day in half of the pots of each genotype. Root exudation was highly correlated with the reduced accumulation of Al in the root tissue (r2 = 0.75 at 72 h). Genotype UF-T2, selected for Al tolerance, extruded 80% more oxalic acid in the presence of Al compared with the other germplasms, indicating that this mechanism is involved with Al tolerance in L. corniculatus. This experiment showed strong evidence that L. corniculatus exhibits Type I tolerance, in which anionic channels are rapidly activated by Al exposure. Exudation of oxalic acid is likely a crucial mechanism that allows the maintenance of L. corniculatus growth when exposed to toxic Al conditions, and this characteristic should be used to identify tolerant genotypes in the future

Uso de soprador contínuo com fluxo vertical de ar no beneficiamento de sementes de erva-mate

Ilex paraguariensis é propagada principalmente por sementes, porém os lotes apresentam alta porcentagem de sementes vazias e deterioradas, tornando-se importante investigar práticas de beneficiamento para aumentar a pureza e viabilidade inicial do lote. O objetivo do estudo foi avaliar o potencial do uso do soprador contínuo com fluxo de ar vertical no beneficiamento de sementes de erva-mate. Sementes de sete matrizes foram expostas a fluxos de ar vertical nas aberturas 0; 3,5; 4,5; 5,5; 6,5 e 7,5 cm, resultando em frações leves (aleta) e pesadas (base). Foram avaliados o percentual de sementes não íntegras (vazias + deterioradas), viáveis, não viáveis e peso de mil sementes (PMS) retidas na base e aleta do soprador. A porcentagem de sementes não íntegras retidas na base do soprador reduziu com o aumento da abertura do fluxo de ar, também houve redução da fração de sementes viáveis e para a porcentagem de sementes não viáveis não houve diferença. O PMS de todas as matrizes apresentou aumento significativo na fração contida na base à medida que aumentou a abertura. Conclui-se que o uso do soprador aumenta a qualidade física e fisiológica das sementes de erva-mate ao promover a remoção de sementes não íntegras (vazias + degradadas). As aberturas de 5,5 e 6,5 cm, com velocidade terminal média de 100 km h-1 são indicadas para o beneficiamento de sementes de erva-mate, considerando a viabilidade e o PMS obtidos neste estudo.Ilex paraguariensis is mainly propagated by seeds, but the lots have a high percentage of empty and deteriorated seeds, making it important to investigate processing practices to increase the purity and initial viability of the lot. The objective of this work was to evaluate the potential of using a continuous blower with vertical air flow in the processing of yerba mate seeds. Seeds from seven mother-plants were exposed to vertical air stream at openings 0; 3.5; 4.5; 5.5; 6.5 and 7.5 cm, resulting in light (fin) and heavy (base) fractions. The percentage of unhealthy seeds (empty + deteriorated), viable, non-viable and a weight of a thousand seeds (WTS) retained in the base and blade of the blower were evaluated. The percentage of unhealthy seeds retained at the base of the blower reduced with the increase of the air flow opening, there was also a reduction in the fraction of viable seeds and for the percentage of non-viable seeds there was no difference. The WTS of all mother-plants had a significant increase in the fraction contained in the base as the opening increased. It is concluded that the use of the blower increases the physical and physiological quality of yerba mate seeds by promoting the removal of non-integral seeds (empty + degraded). The opening of 5.5 and 6.5 cm, with an average terminal velocity of 100 km h-1 are indicated for the cleaning of yerba mate seeds, considering the viability and the WTS obtained in this work

Produção de frutos, produção e qualidade de sementes de tomateiro micro-tom transformado para expressão do gene MT SHSP23.6 mitocondrial em condições de alagamento

The flooding of hydromorphic soils results in significant losses of crop productivity every year, especially in tomato. It is believed that the expression of heats hock proteins, especially sHSPs, play an important role in tolerance to multiple environmental stresses, and may alleviate the damages resulting from the low concentration of oxygen from flooding. Therefore, the presented study aimed to verify the intensity of the high expression of MT sHSP23.6 in the fruits and seeds production of tomato cv Micro-Tom cultivated under flood conditions, as well as in the quality of the seeds produced. Plants of three varieties of tomatoes Micro-Tom were cultivated and submitted to normal irrigation and 72 hours of flooding. The fruits were collected at physiological maturity, and the seeds were extracted manually separating the seeds from the pulp. The following analyzes were performed: Fruit number and yield, seed number and yield, first germination count, germination and tetrazolium test. It is concluded that the high expression of the MT sHSP23.6 mitochondrial gene in tomato cv Micro-Tom increases the production of fruit sand seeds per plant, and assists in the maintenance of fruit and seed production, viability and vigor of the seeds produced under flood stress conditions

ATLANTIC EPIPHYTES: a data set of vascular and non-vascular epiphyte plants and lichens from the Atlantic Forest

Epiphytes are hyper-diverse and one of the frequently undervalued life forms in plant surveys and biodiversity inventories. Epiphytes of the Atlantic Forest, one of the most endangered ecosystems in the world, have high endemism and radiated recently in the Pliocene. We aimed to (1) compile an extensive Atlantic Forest data set on vascular, non-vascular plants (including hemiepiphytes), and lichen epiphyte species occurrence and abundance; (2) describe the epiphyte distribution in the Atlantic Forest, in order to indicate future sampling efforts. Our work presents the first epiphyte data set with information on abundance and occurrence of epiphyte phorophyte species. All data compiled here come from three main sources provided by the authors: published sources (comprising peer-reviewed articles, books, and theses), unpublished data, and herbarium data. We compiled a data set composed of 2,095 species, from 89,270 holo/hemiepiphyte records, in the Atlantic Forest of Brazil, Argentina, Paraguay, and Uruguay, recorded from 1824 to early 2018. Most of the records were from qualitative data (occurrence only, 88%), well distributed throughout the Atlantic Forest. For quantitative records, the most common sampling method was individual trees (71%), followed by plot sampling (19%), and transect sampling (10%). Angiosperms (81%) were the most frequently registered group, and Bromeliaceae and Orchidaceae were the families with the greatest number of records (27,272 and 21,945, respectively). Ferns and Lycophytes presented fewer records than Angiosperms, and Polypodiaceae were the most recorded family, and more concentrated in the Southern and Southeastern regions. Data on non-vascular plants and lichens were scarce, with a few disjunct records concentrated in the Northeastern region of the Atlantic Forest. For all non-vascular plant records, Lejeuneaceae, a family of liverworts, was the most recorded family. We hope that our effort to organize scattered epiphyte data help advance the knowledge of epiphyte ecology, as well as our understanding of macroecological and biogeographical patterns in the Atlantic Forest. No copyright restrictions are associated with the data set. Please cite this Ecology Data Paper if the data are used in publication and teaching events. © 2019 The Authors. Ecology © 2019 The Ecological Society of Americ

Seed production and quality of inter-specific hybrids of the paspalum genus

O objetivo deste trabalho foi determinar o momento de colheita mais adequado para garantir maior produtividade e qualidade de sementes de três híbridos interespecíficos de Paspalum plicatulum x P. guenoarum, nominados ’08Q01’, ‘104026’ e ‘105052’. O experimento foi conduzido na Estação Experimental Agronômica da Universidade Federal do Rio Grande do Sul (EEA/UFRGS), município de Eldorado do Sul. O transplantae foi realizado em linhas num espaçamento de 0,30 m x 0,30 m entre si em parcelas com dimensões de 1,5 x 1,6m. O delineamento experimental foi de blocos ao acaso em parcelas subdivididas, com as épocas de colheita alocadas na parcela e os genótipos na subparcela, com três repetições. As variáveis estudadas foram: densidade de inflorescências, número de racemos e de sementes por inflorescência, comprimento de racemos, rendimento de sementes, massa de sementes debulhadas, massa de mil sementes, primeira contagem de germinação, germinação e índice de velocidade de germinação. Os dados foram submetidos à análise de variância e, em caso de diferença significativa, as médias foram comparadas utilizando o teste de Tukey a 5% de significância. Houve diferença entre os materiais para a produção de sementes. O rendimento de sementes puras viáveis foi superior para híbrido ‘105052’, não diferindo entre as épocas de colheita 2 e 3, atingindo valor de 303,5 kg/ha na época 2. O híbrido ‘104026’ foi o que apresentou maior massa de sementes debulhadas atingindo o valor de 5117,7 kg/ha na terceira época de colheita. As sementes colhidas na terceira época apresentaram maior porcentagem de germinação (55%), primeira contagem de germinação (41%) e índice de velocidade de germinação (17,98). O híbrido ‘105052’ apresentou maior germinação (63%), primeira contagem de germinação (46%) e índice de velocidade de germinação (19,76).The objective of this work was to determine the most appropriate harvest time to ensure greater productivity and seed quality of three interspecific hybrids of Paspalum plicatulum x P. guenoarum, named ’08Q01’, ‘104026’ and ‘105052’. The experiment was carried out at the Agronomic Experimental Station of the Federal University of Rio Grande do Sul (EEA / UFRGS), in the city of Eldorado do Sul. The transplant was carried out in lines spaced 0.30 mx 0.30 m apart in plots with dimensions of 1.5 x 1.6m. The experimental design was randomized blocks in subdivided plots, with the harvest times allocated in the plot and the genotypes in the subplot, with three replications. The studied variables were: density of inflorescences, number of racemes and seeds per inflorescence, length of racemes, seed yield, mass of threshed seeds, mass of a thousand seeds, first germination count, germination and germination speed index. The data were compared using the Tukey test at 5% significance. There was a difference between the materials for seed production. The yield of viable pure seeds was higher for hybrid '105052', not differing between harvest seasons 2 and 3, reaching a value of 303.5 kg / ha in season 2. The hybrid '104026' was the one that presented the highest mass of threshed seeds reaching the value of 5117.7 kg / ha in the third harvest season. The seeds harvested in the third generation of germination generation (55%), first germination count (41%) and germination speed index (17.98). The hybrid '105052' shows higher germination (63%), first germination count (46%) and germination speed index (19.76)