Validação de testes de vigor para sementes de rúcula (Eruca sativa L.)

The limitations of the germination test, which is not efficient in detecting differences in batches with high percentage of twinning, are a major factor that favors the gain space increasing vigor tests. The objective of this study was to evaluate the comparative effectiveness of different tests for evaluating seed vigor rocket (Eruca sativa L.). The experiment was conducted in the Laboratory of Seed Analysis and Experimental Horta in the Department of Plant Sciences, Universidade Federal Rural do Semi-Árido (UFERSA) in Mossoró, RN, during the period from May to August 2011. We used rocket seed, Folha Larga and Cultivada varieties, each represented by four and five lots, respectively. The seeds were evaluated by germination, first count, electrical conductivity, potassium leaching, accelerated aging with saturated and seedling emergence in the field. The experimental design was completely randomized with four replications. The means were submitted to Tukey test at 5% probability and later analysis Pearson correlation at 5% probability. It is found that the electrical conductivity is the most suitable for evaluating the physiological seed rocket.As limitações do teste de germinação, que não é eficiente em detectar diferenças em lotes com alta percentagem de geminação, são um dos principais fatores que favorece o ganho de espaço cada vez maior dos testes de vigor. Objetivou-se com este trabalho avaliar a eficiência comparativa de diferentes testes para a avaliação de vigor de sementes de rúcula (Eruca sativa L.). O experimento foi conduzido no Laboratório de Análise de Sementes e na Horta Experimental do Departamento de Ciências Vegetais da Universidade Federal Rural do Semi-Árido (UFERSA), em Mossoró-RN, durante o período de maio a agosto de 2011. Utilizaram-se sementes de rúcula, cultivares Cultivada e Folha Larga, representadas por quatro e cinco lotes, respectivamente. As sementes foram avaliadas pelos testes de germinação, primeira contagem do teste de germinação, condutividade elétrica, lixiviação de potássio, envelhecimento acelerado com solução saturada e emergência de plântulas em campo. O delineamento experimental foi o inteiramente casualizado com quatro repetições. As médias foram submetidas ao teste Tukey a 5% de probabilidade e posteriormente à análise de correlação de Pearson a 5% de probabilidade. Verifica-se que o teste de condutividade elétrica é o mais indicado para avaliar o potencial fisiológico de sementes de rúcula

Foliar application of biofertilizer in semi-hydroponic lettuce fertigated with saline nutrient solution

Water scarcity in the world is a problem diagnosed especially in countries with large semi-arid regions such as Brazil. Research has been conducted with a view to making use of saline waters as an input for cultivation, particularly in hydroponics, with especial focus on lettuce, the most prominent leafy vegetable in Brazil. The objective of this study was to evaluate the development of lettuce in a semi-hydroponic system fertigated with saline water and under foliar fertilization with biofertilizer. The present study was carried out in a greenhouse located in the experimental area of ​​the Department of Environmental and Technological Sciences (DCAT) of the Federal Rural University of the Semi-Arid Region, in the municipality of Mossoró, RN, Brazil. The experimental design was a randomized complete block design, with treatments arranged in a 2 x 4 factorial scheme, with 4 replicates, two salinity levels of the water used to prepare the nutrient solution (0.5 and 3.5 dS m-1) and four biofertilizer concentrations (0, 20, 40 and 60%) applied by foliar spraying. The evaluated characteristics were: shoot diameter, stem diameter, number of leaves, fresh mass, dry mass, leaf succulence, leaf area and specific leaf area. The use of saline water to prepare the nutrient solution reduces fresh mass and dry mass production in the lettuce crop. The biofertilizer can be applied through the leaves at concentration of up to 20%, promoting greater plant growth.Water scarcity in the world is a problem diagnosed especially in countries with large semi-arid regions such as Brazil. Research has been conducted with a view to making use of saline waters as an input for cultivation, particularly in hydroponics, with especial focus on lettuce, the most prominent leafy vegetable in Brazil. The objective of this study was to evaluate the development of lettuce in a semi-hydroponic system fertigated with saline water and under foliar fertilization with biofertilizer. The present study was carried out in a greenhouse located in the experimental area of ​​the Department of Environmental and Technological Sciences (DCAT) of the Federal Rural University of the Semi-Arid Region, in the municipality of Mossoró, RN, Brazil. The experimental design was a randomized complete block design, with treatments arranged in a 2 x 4 factorial scheme, with 4 replicates, two salinity levels of the water used to prepare the nutrient solution (0.5 and 3.5 dS m-1) and four biofertilizer concentrations (0, 20, 40 and 60%) applied by foliar spraying. The evaluated characteristics were: shoot diameter, stem diameter, number of leaves, fresh mass, dry mass, leaf succulence, leaf area and specific leaf area. The use of saline water to prepare the nutrient solution reduces fresh mass and dry mass production in the lettuce crop. The biofertilizer can be applied through the leaves at concentration of up to 20%, promoting greater plant growth

Cowpea seeds quality and yield according to cropping systems and hydric stress

The cowpea plays an important role in the Brazilian agricultural production, especially in the North and Northeast Regions, where it is widely cultivated by smallholders. Thus, this study aimed at evaluating the physiological quality of cowpea seeds produced under no-tillage and conventional tillage and different periods without irrigation. A randomized blocks design, in a split-plot scheme, with four replications, was used. The plots consisted of cropping systems (no-tillage and conventional tillage), while the subplots consisted of periods without irrigation (2, 6, 10, 14, 18 and 22 days). In the plots, seeds were collected and subjected to the following evaluations: seeds weight per plant, one thousand seeds weight, test weight, seed length and width, moisture content, germination, accelerated aging, field seedling emergence and emergence speed index. Cowpea seeds from plants subjected to hydric stress resulted in lower physiological quality, but were physically bigger and heavier. The no-tillage system provided seeds with better physiological quality. Cowpea plants subjected to hydric stress after flowering produced fewer seeds

EMERGÊNCIA E DESENVOLVIMENTO INICIAL DE PLÂNTULAS DE Cassia grandis L. f. EM FUNÇÃO DE DIFERENTES SUBSTRATOS

Currently, it is aimed to use substrates composed primarily of organic waste in order to reduce costs with chemical fertilizer. In that sense, the experiment was to evaluate different types of substrates for the emergence and early development of seedlings of Cassia grandis L. f. The experiment was carried out in a greenhouse at the Departament of Vegetable Sciences of Federal Rural do Semi-Árido (UFERSA), in Mossoró, Rio Grande do Norte state, Brazil. The substrates used were: sand + carbonized rice husk (in ratios of 1:1, 1:3 and 3:1), plant sand + wood dust (in ratios of 1:1, 1:3 and 3:1), plant sand + coconut fiber (in ratios of 1:1, 1:3 and 3:1), plant sand + chestnut bark (in ratios of 1:1, 1:3 and 3:1) and plant sand (control). The experimental design was a completely randomized design with 13 treatments (combinations of substrates), with four replications of 25 seeds and the means to test for Skot-knot (pr <0.05). We evaluated the following variables: plant emergence, emergence speed, plant height, root length and weight of the aerial part of the plant, root dry mass and total dry mass. According to the results, the substrate plant sand + sawdust (1:1) and plant sand + coconut fiber (1:3) showed higher values, providing better results in emergence, weight of the aerial part of the plant, length of the aerial part of the plant, root dry mass and root length. It was found that the substrate compounds sand plant and chestnut bark (1:3) is harmful to the emergence of seedling of Cassia grandis. Atualmente, busca-se utilizar substratos constituídos, principalmente, de resíduos orgânicos, a fim de diminuir os custos com adubação química. Nesse sentido, o experimento teve como objetivo avaliar diferentes tipos de substratos para a emergência e desenvolvimento inicial de plântulas de cássia-rosa (Cassia grandis L. f.). O experimento foi conduzido em casa de vegetação do Departamento de Ciências Vegetais da Universidade Federal Rural do Semiárido (UFERSA), em Mossoró - RN, no período de abril a maio de 2012. Os substratos utilizados foram: terra vegetal + palha de arroz (nas proporções de 1:1, 1:3 e 3:1), terra vegetal + pó de madeira (nas proporções de 1:1, 1:3 e 3:1), terra vegetal + fibra de coco (nas proporções de 1:1, 1:3 e 3:1), terra vegetal + casca de castanha-de-caju (nas proporções de 1:1, 1:3 e 3:1) e terra vegetal (testemunha). O delineamento estatístico utilizado foi o inteiramente casualizado, com 13 tratamentos (combinações dos substratos), em quatro repetições de 25 sementes e as médias submetidas ao teste de Skot-knott (pr<0,05). Foram avaliadas as variáveis porcentagem e velocidade de emergência, comprimento da parte aérea, comprimento de raiz e massa seca da parte aérea, massa seca da raiz e massa seca total. De acordo com os resultados, os substratos terra vegetal + pó de madeira (1:1) e terra vegetal + fibra de coco (1:3) foram os mais apropriados, proporcionando melhores resultados em emergência, massa seca da parte aérea, comprimento da parte aérea, massa seca da raiz e comprimento da raiz. Por outro lado, verificou-se que o substrato composto com terra vegetal e casca de castanha-de-caju (1:3) mostrou-se inadequado para a emergência de plântulas de cássia-rosa

Pre-germination treatments with plant growth regulators and bioactivators attenuate salt stress in melon: effects on germination and seedling development

The scarcity of surface water has led to the use of underground sources as an alternative for crop irrigation by farmers in semi-arid regions. However, these water sources generally have high salinity, which prevents agricultural production. The objective of this study was to determine the effects of pre-germination treatments with plant growth regulators and bioactivators on melon seeds to attenuate salt stress caused by irrigation water during germination and seedling development. Two trials were carried out separately with the hybrids, Goldex and Grand Prix. The design was completely randomized in a 4 × 3 factorial scheme (four seed treatments and three dilutions of irrigation water). Seeds were treated with salicylic acid and gibberellic acid and the insecticide, thiamethoxam, in addition to the control. Local supply water, artesian well groundwater, and dilution of these waters at a 1:1 ratio were employed for irrigation. Fourteen days after sowing, morphological and physiological analyses were performed, and the material was collected for biochemical determination. The use of saline well water affected the initial development of melon seedlings of the Goldex and Grand Prix hybrids. Pre-germination treatment of Goldex hybrid seeds with gibberellic acid was inefficient at mitigating salt stress. However, the effects of irrigation water salinity on Grand Prix melon seeds pretreated with salicylic acid and thiamethoxam were attenuated

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

Validação de testes de vigor para sementes de rúcula (Eruca sativa L.)

The limitations of the germination test, which is not efficient in detecting differences in batches with high percentage of twinning, are a major factor that favors the gain space increasing vigor tests. The objective of this study was to evaluate the comparative effectiveness of different tests for evaluating seed vigor rocket (Eruca sativa L.). The experiment was conducted in the Laboratory of Seed Analysis and Experimental Horta in the Department of Plant Sciences, Universidade Federal Rural do Semi-Árido (UFERSA) in Mossoró, RN, during the period from May to August 2011. We used rocket seed, Folha Larga and Cultivada varieties, each represented by four and five lots, respectively. The seeds were evaluated by germination, first count, electrical conductivity, potassium leaching, accelerated aging with saturated and seedling emergence in the field. The experimental design was completely randomized with four replications. The means were submitted to Tukey test at 5% probability and later analysis Pearson correlation at 5% probability. It is found that the electrical conductivity is the most suitable for evaluating the physiological seed rocket.As limitações do teste de germinação, que não é eficiente em detectar diferenças em lotes com alta percentagem de geminação, são um dos principais fatores que favorece o ganho de espaço cada vez maior dos testes de vigor. Objetivou-se com este trabalho avaliar a eficiência comparativa de diferentes testes para a avaliação de vigor de sementes de rúcula (Eruca sativa L.). O experimento foi conduzido no Laboratório de Análise de Sementes e na Horta Experimental do Departamento de Ciências Vegetais da Universidade Federal Rural do Semi-Árido (UFERSA), em Mossoró-RN, durante o período de maio a agosto de 2011. Utilizaram-se sementes de rúcula, cultivares Cultivada e Folha Larga, representadas por quatro e cinco lotes, respectivamente. As sementes foram avaliadas pelos testes de germinação, primeira contagem do teste de germinação, condutividade elétrica, lixiviação de potássio, envelhecimento acelerado com solução saturada e emergência de plântulas em campo. O delineamento experimental foi o inteiramente casualizado com quatro repetições. As médias foram submetidas ao teste Tukey a 5% de probabilidade e posteriormente à análise de correlação de Pearson a 5% de probabilidade. Verifica-se que o teste de condutividade elétrica é o mais indicado para avaliar o potencial fisiológico de sementes de rúcula

Physiological maturation of cowpea seeds

The seed maturation process is genetically controlled and involves an arranged sequence of morphological and physiological changes extending from fertilization to its total independence from the mother-plant. These changes also include a set of preparatory phases for the germination process, which are characterized for the synthesis and accumulation of nutrient reserves. Thereby, this study was developed aiming at assessing development and physiological quality of cowpea seeds during maturation process. To this, the cowpea pods of cultivar BRS-Guariba were harvested from the tenth day after anthesis (DAA) until the twenty sixth DAA, with four days intervals. Immediately after each harvest, seeds were manually extracted from the pods and then subjected to the following determinations: moisture content, first count of germination, final germination percentage, length of shoots and roots, hypocotyl diameter, and seedling dry mass. The experiment was conducted in a completely randomized design, with five treatments (DAA), and four replications to each treatment. Results have shown that cowpea seeds have fairly fast physiological maturation, and that seeds harvested between 14 and 18 DAA have better vigor as well as higher germination rates; thus the harvest performed during this period does not cause damages to seeds