To understand the production cycle of a particular cultivar in a given region, it is necessary to obtain information related to its phenology and the accumulated degree days. The purpose of this study was to evaluate the phenological cycle of citrus species grafted onto two rootstocks and grown in the Low-Middle Region of the São Francisco River Basin, in particular with respect to accumulated degree days. The experiment was conducted using ‘Rubi’ and ‘Pera D-12’ oranges and ‘Page’ mandarins. Two rootstocks were used, namely ‘Cravo’ and ‘Volkameriano’ lemon species that were drip irrigated in the Campo Experimental de Bebedouro, an experimental field owned by Embrapa Semiárido. ‘Page’ mandarins with ‘Cravo’ or ‘Volkameriano’ rootstocks exhibited a subperiod (0-10) of 183.32 and 181.24 days, respectively. Meanwhile, ‘Pera D-12’ and ‘Rubi’ oranges with ‘Cravo’ rootstocks had values of 249.57 and 178.58 days, respectively, while those with ‘Volkameriano’ rootstocks had values of 226.35 and 200.41 days, respectively. The accumulated degree days were measured from the initial sprouting to harvesting, which took place when the fruits presented a soluble solids/titratable acidity ratio equal to or greater than 12. ‘Page’ mandarins required 2,720 degree days, whereas ‘Pera D-12’ and ‘Rubi’ oranges required approximately 3,390 and 2,280 degree days, respectively. Finally, ‘Pera D-12’ and ‘Rubi’ oranges with either rootstock presented cycles characterized as mid-season and precocious, respectively, while ‘Page’ mandarins had precocious cycles.

To understand the production cycle of a particular cultivar in a given region, it is necessary to obtain information related to its phenology and the accumulated degree days. The purpose of this study was to evaluate the phenological cycle of citrus species grafted onto two rootstocks and grown in the Low-Middle Region of the São Francisco River Basin, in particular with respect to accumulated degree days. The experiment was conducted using ‘Rubi’ and ‘Pera D-12’ oranges and ‘Page’ mandarins. Two rootstocks were used, namely ‘Cravo’ and ‘Volkameriano’ lemon species that were drip irrigated in the Campo Experimental de Bebedouro, an experimental field owned by Embrapa Semiárido. ‘Page’ mandarins with ‘Cravo’ or ‘Volkameriano’ rootstocks exhibited a subperiod (0–10) of 183.32 and 181.24 days, respectively. Meanwhile, ‘Pera D-12’ and ‘Rubi’ oranges with ‘Cravo’ rootstocks had values of 249.57 and 178.58 days, respectively, while those with ‘Volkameriano’ rootstocks had values of 226.35 and 200.41 days, respectively. The accumulated degree days were measured from the initial sprouting to harvesting, which took place when the fruits presented a soluble solids/titratable acidity ratio equal to or greater than 12. ‘Page’ mandarins required 2,720 degree days, whereas ‘Pera D-12’ and ‘Rubi’ oranges required approximately 3,390 and 2,280 degree days, respectively. Finally, ‘Pera D-12’ and ‘Rubi’ oranges with either rootstock presented cycles characterized as mid-season and precocious, respectively, while ‘Page’ mandarins had precocious cycles. | Para definir o ciclo de produção de uma cultivar em uma determinada região são necessárias informações relacionadas à fenologia e ao acúmulo de graus-dia para a sua produção. O objetivo deste trabalho foi avaliar o ciclo fenológico de espécies cítricas, enxertadas sobre dois Porta- enxertos em função do acúmulo de graus-dias nas condições do Submédio São Francisco. O experimento foi conduzido com duas laranjeiras ‘Rubi’ e ‘Pera D-12’ e uma tangerineira ‘Page’, sobre dois porta-enxertos: limoeiros ‘Cravo’ e limoeiro ‘Volkameriano’, irrigadas por gotejamento, no Campo Experimental de Bebedouro, pertencente à Embrapa Semiárido. Para a tangerineira ‘Page’ nos porta-enxertos ‘Cravo’ e ‘Volkameriano’, o subperíodo (0-10) foi de 183,32 dias e 181,24 dias, respectivamente; para as laranjeiras ‘Pera D-12’ e ‘Rubi’, sobre o porta-enxerto ‘Cravo’, foi de 249,57 dias e 178,58 dias e, para o ‘Volkameriano’, foi de 226,35 dias e 200,41dias, respectivamente. Desde a emissão da brotação até a colheita, fase em que os frutos apresentaram valor de “ratio” igual ou superior a 12, para a tangerineira ‘Page’ foram necessários aproximadamente 2.720 graus-dias, e para as laranjeiras ‘Pera D12’ e ‘Rubi’, aproximadamente 3.390 e 2.280 graus-dias, respectivamente. As laranjeiras ‘Pera D-12’ e ‘Rubi’, enxertadas sobre os dois porta-enxertos apresentaram ciclos caracterizados como sendo de meia-estação e precoce, respectivamente, e a tangerineira ‘Page’, ciclo precoce.

This study aimed to characterize three natural populations of mangabeira (Hancornia speciosa) located in parts of the Cerrado in the region of Porto Nacional, State of Tocantins, as well as to evaluate phenotypic variability in individual plants based on the physicochemical properties of their fruits. Ten genotypes were selected from each population, and 20 fruits of each genotype were collected for analysis. Fruits were analyzed for transverse and longitudinal diameters, total mass, pulp mass and yield, and number and fresh mass of seeds. Two seeds were taken from each fruit for the measurement of longitudinal and transverse diameter and thickness. Furthermore, pH and soluble solids were measured in the total pulp of each genotype. Descriptive statistics were performed on the data from morphological characterization, and populations were compared by the Kruskal-Wallis test, followed by Dunn's test at 5% probability level. The relationship between variables was estimated by the Spearman’s correlation coefficient. Phenotypic variability was verified using the principal component analysis. All three natural populations of mangabeira investigated here exhibited similar characteristics regarding fruit morphology and pH. Significant differences were detected only in the transverse diameter of the seed (Canaã had the highest value) and for total soluble solids content (Providência had the highest value). Significant correlations were found for corresponding morphological variables and pH in each population, except for several negative correlations that were observed in the Canaã population, which produced more homogeneous fruit. The Providência population presented the largest and most massive fruit. The greatest phenotypic variabilities were observed in the São Judas Tadeu and Providência populations.

This study aimed to characterize three natural populations of mangabeira (Hancornia speciosa) located in parts of the Cerrado in the region of Porto Nacional, State of Tocantins, as well as to evaluate phenotypic variability in individual plants based on the physicochemical properties of their fruits. Ten genotypes were selected from each population, and 20 fruits of each genotype were collected for analysis. Fruits were analyzed for transverse and longitudinal diameters, total mass, pulp mass and yield, and number and fresh mass of seeds. Two seeds were taken from each fruit for the measurement of longitudinal and transverse diameter and thickness. Furthermore, pH and soluble solids were measured in the total pulp of each genotype. Descriptive statistics were performed on the data from morphological characterization, and populations were compared by the Kruskal-Wallis test, followed by Dunn's test at 5% probability level. The relationship between variables was estimated by the Spearman’s correlation coefficient. Phenotypic variability was verified using the principal component analysis. All three natural populations of mangabeira investigated here exhibited similar characteristics regarding fruit morphology and pH. Significant differences were detected only in the transverse diameter of the seed (Canaã had the highest value) and for total soluble solids content (Providência had the highest value). Significant correlations were found for corresponding morphological variables and pH in each population, except for several negative correlations that were observed in the Canaã population, which produced more homogeneous fruit. The Providência population presented the largest and most massive fruit. The greatest phenotypic variabilities were observed in the São Judas Tadeu and Providência populations. | O presente estudo teve como objetivo caracterizar três populações naturais de mangabeira (Hancornia speciosa Gomes) localizadas em áreas de Cerrado na região de Porto Nacional-TO e estudar a variabilidade fenotípica através de atributos físico-químicos de frutos. Foram selecionados dez genótipos em cada população e coletados vinte frutos de cada genótipo para análise. Nos frutos foram mensurados: o diâmetro transversal e longitudinal, a massa total, a massa e o rendimento de polpa, o número de sementes e a massa fresca das sementes. De cada fruto foram retiradas duas sementes e mensurados o diâmetro longitudinal, transversal e espessura. Da polpa total de cada genótipo foram mensurados o pH e sólidos solúveis. Para caracterização morfológica foi realizada estatística descritiva, a comparação entre as populações foi realizada através do teste de Kruskal-Wallis seguido do teste de Dunn a 5% de probabilidade. A relação entre as variáveis foi estimada pelo coeficiente de correlação de Spearman. Para o estudo da variabilidade fenotípica foi realizada a análise de componentes principais. As populações naturais de mangabeira estudadas apresentam características semelhantes quanto à morfologia do fruto e pH, sendo encontrado diferenças significativas apenas para o diâmetro transversal da semente, com maior valor para Canaã e sólidos solúveis totais, com maior valor para Providência. As correlações significativas em cada população ocorrem para as mesmas variáveis morfológicas e pH, com exceção das correlações negativas que ocorreram na população Canaã que se destacou por apresentar frutos mais homogêneos. Providência apresentou frutos maiores e com maior massa. Nas populações São Judas Tadeu e Providência foram observadas maiores variabilidades fenotípicas.

The objective of the present study was to evaluate the tolerance to cadmium (Cd) of sunflower genotypes grown in greenhouse conditions, and the effectiveness of using photosynthetic parameters as physiological indicators of this tolerance. Seeds of two sunflower genotypes previously identified as tolerant (H358) and Cd-sensitive (AG960) to Cd were used. The seeds were germinated in plastic cups containing plant substrate; after 9 days, the seedlings were transplanted to plastic basins containing a nutrient solution with 0 or 10 µM of Cd, where they remained for 16 days. Samples of the plants were harvested every 5 days. The experiment was carried out in a randomized complete design, using a 4×2×2 factorial arrangement (4 days of grown in a nutrient solution with Cd, 2 sunflower genotypes, and 2 Cd levels) with four replications. Cd stress decreased CO2 net assimilation, stomatal conductance, carboxylation efficiency, photosynthetic pigment contents, potential quantum yield (Fv/Fm), and effective quantum yield of plants of the two evaluated genotypes. The decrease in photosynthetic rates of these plants was caused by both stomatal and non-stomatal limitations. Plants of the AG960 genotype showed more pronounced deleterious effects due to Cd stress than those of the H358 genotype. Thus, CO2 net assimilation rate, stomatal conductance, and chloroplast pigment content are good physiological indicators of sunflower tolerance to Cd and can at least in part, explain the greater tolerance of the H358 genotype to Cd stress when compared to the AG960 genotype.

The objective of the present study was to evaluate the tolerance to cadmium (Cd) of sunflower genotypes grown in greenhouse conditions, and the effectiveness of using photosynthetic parameters as physiological indicators of this tolerance. Seeds of two sunflower genotypes previously identified as tolerant (H358) and Cd-sensitive (AG960) to Cd were used. The seeds were germinated in plastic cups containing plant substrate; after 9 days, the seedlings were transplanted to plastic basins containing a nutrient solution with 0 or 10 µM of Cd, where they remained for 16 days. Samples of the plants were harvested every 5 days. The experiment was carried out in a randomized complete design, using a 4×2×2 factorial arrangement (4 days of grown in a nutrient solution with Cd, 2 sunflower genotypes, and 2 Cd levels) with four replications. Cd stress decreased CO2 net assimilation, stomatal conductance, carboxylation efficiency, photosynthetic pigment contents, potential quantum yield (Fv/Fm), and effective quantum yield of plants of the two evaluated genotypes. The decrease in photosynthetic rates of these plants was caused by both stomatal and non-stomatal limitations. Plants of the AG960 genotype showed more pronounced deleterious effects due to Cd stress than those of the H358 genotype. Thus, CO2 net assimilation rate, stomatal conductance, and chloroplast pigment content are good physiological indicators of sunflower tolerance to Cd and can at least in part, explain the greater tolerance of the H358 genotype to Cd stress when compared to the AG960 genotype. | O presente estudo foi conduzido em casa de vegetação objetivando-se demonstrar a tolerância ao cádmio (Cd) em genótipos de girassol e avaliar a eficácia dos parâmetros fotossintéticos como indicadores fisiológicos dessa tolerância. Para isto, foram utilizadas sementes de dois genótipos de girassol previamente identificados como tolerante (H358) e sensível (AG960) ao Cd.As sementes foram germinadas em copos plásticos contendo substrato vegetal e, após 9 dias, as plântulas foram transferidas para bacias plásticas com solução nutritiva contendo 0 ou 10 µM de Cd , onde permaneceram por 16 dias. As plantas foram coletadas a cada 5 dias. O delineamento experimental foi o inteiramente casualizado, em um arranjo fatorial 4 (dias de exposição) × 2 (genótipos) × 2 (níveis de Cd), com quatro repetições. A exposição ao Cd reduziu a taxa de assimilação líquida do CO2, a condutância estomática e a eficiência de carboxilação, bem como os teores de todos os pigmentos fotossintéticos, a razão Fv/Fm e o YII das plantas de ambos os genótipos estudados. Demonstrando que a redução na taxa fotossintética dessas plantas foi ocasionada tanto por limitações estomáticas como não-estomáticas. Os efeitos deletérios do Cd foram mais pronunciados no genótipo AG960 em comparação com o H358. Assim, as variáveis A, gs e os teores de pigmentos mostraram-se bons indicadores fisiológicos da tolerância do girassol ao estresse por Cd e podem, ao menos em parte, explicar a maior tolerância do genótipo H358 em relação ao AG960.

The Brazilian bocachico, Prochilodus brevis, is a rheophilic fish. Although there is evidence that this species shows reproductive seasonality in the wild, in captivity hormonal induction techniques allow semen sampling in different seasons. This study aimed to compare the kinetics, morphology and biochemical composition of the semen of Brazilian bocachico in captivity when hormonally induced to breed in the reproductive and non-reproductive seasons. During sampling spermiation was hormonally induced in breeders. The concentrations of total protein, glucose, fructose, triglyceride, calcium and chloride were evaluated with biochemical kits. The pH data (6.5 to 8.5) suggest semen requires alkaline conditions, as expected for freshwater fish. Seminal plasma contained more protein (1.51 ± 0.06 dL g-1), glucose (79.44 ± 1.88 mg dL-1) and triglycerides (61.59 ± 8.10 mg dL-1) in the non-reproductive than the reproductive season, but calcium ions (15.98 ± 1.02 mg dL-1) showed the opposite pattern. There was a significant seasonal difference in sperm morphology, with a higher percentage of normal sperm in the reproductive season. From these data it can be concluded that the physical, kinetic, morphological and biochemical characteristics of semen of captive Prochilodus brevis are influenced by reproductive season.

The Brazilian bocachico, Prochilodus brevis, is a rheophilic fish. Although there is evidence that this species shows reproductive seasonality in the wild, in captivity hormonal induction techniques allow semen sampling in different seasons. This study aimed to compare the kinetics, morphology and biochemical composition of the semen of Brazilian bocachico in captivity when hormonally induced to breed in the reproductive and non-reproductive seasons. During sampling spermiation was hormonally induced in breeders. The concentrations of total protein, glucose, fructose, triglyceride, calcium and chloride were evaluated with biochemical kits. The pH data (6.5 to 8.5) suggest semen requires alkaline conditions, as expected for freshwater fish. Seminal plasma contained more protein (1.51 ± 0.06 dL g-1), glucose (79.44 ± 1.88 mg dL-1) and triglycerides (61.59 ± 8.10 mg dL-1) in the non-reproductive than the reproductive season, but calcium ions (15.98 ± 1.02 mg dL-1) showed the opposite pattern. There was a significant seasonal difference in sperm morphology, with a higher percentage of normal sperm in the reproductive season. From these data it can be concluded that the physical, kinetic, morphological and biochemical characteristics of semen of captive Prochilodus brevis are influenced by reproductive season. | O curimatã comum Prochilodus brevis caracteriza-se como um peixe reofílico. Na natureza, esses animais apresentam sazonalidade reprodutiva, porém em cativeiro, técnicas de indução hormonal, permitem a coleta de sêmen em diferentes períodos do ano. Objetivou-se comparar a cinética, a morfologia e a composição física e bioquímica do sêmen de curimatã comum induzidos à reprodução em cativeiro com uso de hormônio, na estação reprodutiva e não reprodutiva. As concentrações de proteínas totais, glicose, frutose, triglicerídeo, cálcio e cloreto foram avaliadas através de kits bioquímicos e analisadas em espectrofotômetro. Os dados de pH do sêmen, sugerem condição alcalina do sêmen dentro do esperado para peixes de água doce (6,5 a 8,5). A quantidade de proteínas totais (1,51 ± 0,06 g dL-1), glicose (79,44 ± 1,88 mg dL-1) e triglicerídeos (61,59 ± 8,10 mg dL-1) no plasma seminal apresentaram uma maior concentração na estação não reprodutiva. Enquanto que o oposto foi verificado para os íons cálcio (15,98 ± 1,02 mg dL-1). Houve diferença significativa, na morfologia do espermatozoide na estação reprodutiva, com uma porcentagem de espermatozoides normais superior em relação à estação não reprodutiva. Assim, pode-se concluir que características físicas, bioquímicas, cinéticas e morfológicas do sêmen de curimatã comum, mantidos em cativeiro, sofrem influência da estação reprodutiva.

Potato (Solanum tuberosum L.) is a nutritionally demanding crop, and phosphorus (P) is a nutrient that exerts a large effect on tuber yield. However, as the availability of P is influenced by soil texture, there are doubts about how P supplementation affects the growth and yield of potato plants in different soil textures. Thus, here we aimed to evaluate the effect of P fertilization and soil texture on the nutrition, growth, tuber yield, and P use efficiency (PUE) of potato plants. The experiment was conducted under greenhouse conditions in a randomized block design with a 4×2 factorial scheme and five replications. The treatments were represented by four P rates (10, 50, 100, and 200 mg dm-3 P) and two soil textures (clayey and sandy). The concentrations of P, Ca, and Mg in the leaves were higher in sandy soil, and P rates increased the concentrations of N, P, and Ca in the leaves of potato plants. Phosphorus fertilization increased plant growth, the amount of P accumulated in the shoot, and tuber yield in both soils; this trend was stronger in the potato cultivated in the clayey soil than in the sandy soil. The applied-PUE was not affected by soil texture. In the potato cultivated in the sandy soil, the taken up-PUE was reduced due to the decrease in dry matter production and an increase in P concentration in the organs of the plant with higher P fertilizer rates.

Potato (Solanum tuberosum L.) is a nutritionally demanding crop, and phosphorus (P) is a nutrient that exerts a large effect on tuber yield. However, as the availability of P is influenced by soil texture, there are doubts about how P supplementation affects the growth and yield of potato plants in different soil textures. Thus, here we aimed to evaluate the effect of P fertilization and soil texture on the nutrition, growth, tuber yield, and P use efficiency (PUE) of potato plants. The experiment was conducted under greenhouse conditions in a randomized block design with a 4×2 factorial scheme and five replications. The treatments were represented by four P rates (10, 50, 100, and 200 mg dm-3 P) and two soil textures (clayey and sandy). The concentrations of P, Ca, and Mg in the leaves were higher in sandy soil, and P rates increased the concentrations of N, P, and Ca in the leaves of potato plants. Phosphorus fertilization increased plant growth, the amount of P accumulated in the shoot, and tuber yield in both soils; this trend was stronger in the potato cultivated in the clayey soil than in the sandy soil. The applied-PUE was not affected by soil texture. In the potato cultivated in the sandy soil, the taken up-PUE was reduced due to the decrease in dry matter production and an increase in P concentration in the organs of the plant with higher P fertilizer rates. | A batata (Solanum tuberosum L.) é uma cultura nutricionalmente exigente e o fósforo (P) é um dos nutrientes que exerce grande efeito sobre a produtividade de tubérculos. Porém, como a disponibilidade de P é influenciada pela textura do solo, existem dúvidas de como o fornecimento de P afeta o crescimento e a produtividade das plantas de batata em solos de texturas diferentes. Assim, objetivou-se com esta pesquisa avaliar o efeito da adubação fosfatada e da textura do solo na nutrição, crescimento, produtividade e eficiência de uso (EU) do P das plantas de batata. O experimento foi conduzido em casa de vegetação no delineamento de blocos casualizados em esquema fatorial 4×2, com cinco repetições. Os tratamentos foram representados por quatro doses de P (10, 50, 100 e 200 mg dm-3 P) e duas texturas de solo (argiloso e arenoso). Os teores foliares de P, Ca e Mg foram maiores no solo arenoso e as doses de P aumentaram os teores de N, P e Ca nas folhas. A adubação fosfatada aumentou o crescimento das plantas, a quantidade de P acumulada na parte aérea e a produtividade de tubérculos em ambos os solos, porém, de forma mais expressiva e até maiores doses na batata cultivada no solo argiloso. A EU do P aplicado não foi afetada pela textura do solo. Na batata cultivada no solo arenoso, a EU do P absorvido foi reduzida em função da diminuição na produção de MS e aumento nos teores de P nos órgãos da planta com fornecimento de altas doses de P.

The cultivation of irrigated guava in semi-arid areas highlights the need for information regarding its responses to irrigation water quality and the fertilization management that enables its exploitation. Thus, this study aimed to evaluate the effect of water salinity and nitrogen (N) doses on the growth and physiology of the guava cv. ‘Paluma’. The experiments was conducted in drainage lysimeters under field conditions in an experimental area at the Center of Sciences and Agri-Food Technology of the Federal University of Campina Grande (CCTA/UFCG), Campus II, in Pombal, PB, Brazil. The experiment had a randomized block design, and treatments consisted of a 5 x 4 factorial arrangement corresponding to five levels of irrigation water electrical conductivity, ECw (0.3, 1.1, 1.9, 2.7, and 3.5 dS m-1), and four N doses (70, 100, 130, and 160% of the recommended N dose). The 100% dose corresponded to 541.1 mg of N dm-3 of soil. Increments in irrigation water salinity from 0.3 dS m-1 led to a reduction in stomatal conductance, internal CO2 concentration, CO2 assimilation rate, transpiration, instantaneous water use efficiency, the number of leaves and branches, stem diameter, and absolute and relative growth rates. Nitrogen doses ranging from 378.7 to 865.7 mg of N dm-3 of soil did not affect gas exchange and plant growth. Although ‘Paluma’ guava growth was affected by increases in water salinity, these plants can be irrigated using water of up to 1.42 dS m-1 with an acceptable reduction of 10% in growth variables. The interaction between irrigation water salinity and N fertilization had no significant effect on any of the variables studied.

The cultivation of irrigated guava in semi-arid areas highlights the need for information regarding its responses to irrigation water quality and the fertilization management that enables its exploitation. Thus, this study aimed to evaluate the effect of water salinity and nitrogen (N) doses on the growth and physiology of the guava cv. ‘Paluma’. The experiments was conducted in drainage lysimeters under field conditions in an experimental area at the Center of Sciences and Agri-Food Technology of the Federal University of Campina Grande (CCTA/UFCG), Campus II, in Pombal, PB, Brazil. The experiment had a randomized block design, and treatments consisted of a 5 x 4 factorial arrangement corresponding to five levels of irrigation water electrical conductivity, ECw (0.3, 1.1, 1.9, 2.7, and 3.5 dS m-1), and four N doses (70, 100, 130, and 160% of the recommended N dose). The 100% dose corresponded to 541.1 mg of N dm-3 of soil. Increments in irrigation water salinity from 0.3 dS m-1 led to a reduction in stomatal conductance, internal CO2 concentration, CO2 assimilation rate, transpiration, instantaneous water use efficiency, the number of leaves and branches, stem diameter, and absolute and relative growth rates. Nitrogen doses ranging from 378.7 to 865.7 mg of N dm-3 of soil did not affect gas exchange and plant growth. Although ‘Paluma’ guava growth was affected by increases in water salinity, these plants can be irrigated using water of up to 1.42 dS m-1 with an acceptable reduction of 10% in growth variables. The interaction between irrigation water salinity and N fertilization had no significant effect on any of the variables studied. | O cultivo da goiabeira irrigada nas áreas semiáridas evidencia a necessidade de informações a respeito de suas respostas à qualidade da água de irrigação e ao manejo da adubação que possibilite sua exploração. Assim, objetivou-se estudar o efeito da salinidade da água combinada com doses de nitrogênio no crescimento e fisiologia da goiabeira cv. ‘Paluma’, em experimento conduzido em lisímetros de drenagem sob condições de campo em uma área experimental no Centro de Ciência e Tecnologia Agroalimentar da Universidade Federal de Campina Grande (CCTA/UFCG), Campus II de Pombal, PB. O delineamento experimental utilizado foi de blocos casualizados, com tratamentos arranjados em esquema fatorial 5 x 4, relativos a cinco níveis de condutividade elétrica da água de irrigação – CEa (0,3; 1,1; 1,9; 2,7 e 3,5 dS m-1) e quatro doses de nitrogênio (70, 100, 130 e 160% de N recomendada), sendo a dose referente a 100% correspondeu a 541,1 mg de N dm-3 de solo. O aumento da salinidade da água de irrigação a partir de 0,3 dS m-1 promoveu redução na condutância estomática, concentração interna de CO2, taxa de assimilação de CO2, transpiração, eficiência instantânea no uso da água, número de folhas e ramos, diâmetro de caule, taxa de crescimento absoluto e relativo. Doses de nitrogênio variando de 378,7 a 865,7 mg de N dm-3 de solo não afetaram as trocas gasosas e o crescimento das plantas. Apesar do crescimento da goiabeira cv. Paluma ser afetado com o aumento da salinidade, é possível irrigar com água de até 1,42 dS m-1 ocorrendo redução aceitável de 10% nas variáveis de crescimento. Não houve efeito significativo da interação entre salinidade da água de irrigação e doses de adubação nitrogenada em nenhuma variável estudada.

Carnauba (Copernicia prunifera) is a forest species with multiple uses, and is of great economic and social importance for several communities involved in extractive agriculture in northeastern Brazil. However, there are few studies on genetic variability in this species. Thus, this work aimed to produce information about the genetic characterization of C. prunifera seeds and seedlings, using provenance and progeny evaluations. A progeny test was performed in a plant nursery, using seeds of 36 matrices sampled in the municipalities of Mossoró and Apodi (Rio Grande do Norte State), and Russas and Icapuí (Ceará State). Three groups were derived according to the spatial distance between the collected matrices. Biometric analyses of the seeds were performed, adopting a completely randomized experimental design, with four replicates of 25 seeds in each analysis. A randomized block design (five replicates and five plants per plot) was used at the seedling production phase. The data evaluated included the emergence speed index, emergence percentage, leaf size, leaf base diameter, and survival (at 30, 60, and 90 days after sowing). The restricted maximum likelihood method was used in the statistical analysis, with the aid of SELEGEN software. In order to evaluate genetic variability in the C. prunifera population samples, it was verified that the juvenile characters presented a moderate genetic control. The three groups of spatially delimited matrices presented no significant genetic differences. This information may assist in the development of forestry practice for this species.

Carnauba (Copernicia prunifera) is a forest species with multiple uses, and is of great economic and social importance for several communities involved in extractive agriculture in northeastern Brazil. However, there are few studies on genetic variability in this species. Thus, this work aimed to produce information about the genetic characterization of C. prunifera seeds and seedlings, using provenance and progeny evaluations. A progeny test was performed in a plant nursery, using seeds of 36 matrices sampled in the municipalities of Mossoró and Apodi (Rio Grande do Norte State), and Russas and Icapuí (Ceará State). Three groups were derived according to the spatial distance between the collected matrices. Biometric analyses of the seeds were performed, adopting a completely randomized experimental design, with four replicates of 25 seeds in each analysis. A randomized block design (five replicates and five plants per plot) was used at the seedling production phase. The data evaluated included the emergence speed index, emergence percentage, leaf size, leaf base diameter, and survival (at 30, 60, and 90 days after sowing). The restricted maximum likelihood method was used in the statistical analysis, with the aid of SELEGEN software. In order to evaluate genetic variability in the C. prunifera population samples, it was verified that the juvenile characters presented a moderate genetic control. The three groups of spatially delimited matrices presented no significant genetic differences. This information may assist in the development of forestry practice for this species. | A carnaubeira (Copernicia prunifera) é uma espécie florestal que apresenta múltiplos usos e de grande importância econômica e social para várias famílias extrativistas no Nordeste brasileiro. Entretanto, são escassos os estudos a respeito da variabilidade genética da espécie. Assim, este trabalho buscou gerar informações em relação à caracterização genética de sementes e mudas de Copernicia prunifera, avaliando procedências e progênies. Instalou-se um teste de progênies, em viveiro, a partir de sementes de 36 matrizes amostradas nos Municípios de Mossoró e Apodi, no Estado do Rio Grande do Norte; e em Russas e Icapuí, no Estado do Ceará. A partir da distância espacial entre as matrizes coletadas foram formados três grupos. Foram realizadas análises biométricas das sementes, adotando o delineamento experimental inteiramente casualizado, com quatro repetições de 25 sementes para cada análise. O delineamento em blocos casualizados com cinco repetições e cinco plantas por parcela foi empregado na fase de produção de mudas. Os dados avaliados incluíram: índice de velocidade de emergência, porcentagem de emergência, tamanho da folha, diâmetro da base da folha e sobrevivência (aos 30, 60 e 90 dias após a semeadura). A metodologia de máxima verossimilhança restrita foi utilizada para a análise estatística, com o auxílio do software SELEGEN. Verificou-se que os caracteres juvenis apresentam controle genético médio, podendo ser utilizados para avaliação da variabilidade genética de amostras de populações da espécie. Os três grupos de matrizes delimitados espacialmente não apresentam diferenças genéticas significativas. Essas informações podem auxiliar no desenvolvimento da silvicultura da espécie.

Irrigation with saline water is a worldwide necessity an excess of salts in water or in soil causes growth inhibition, and negatively affects the productivity of many crops. Application of nitrogen fertilizers may be a way of mitigating the effects of salts on plants. The aim of this study was to evaluate the accumulation of biomass and the chlorophyll pigment content in jackfruit seedlings irrigated with water of increasing salinity level in soil with nitrogen sources. The treatments were distributed in randomized blocks with four replicates and three plants per plot, arranged in a 5 × 3 factorial scheme, related to electrical conductivity levels of the irrigation water of 0.3, 1.0, 2.0, 3.0 and 4.0 dS m-1, in soil without nitrogen, with ammonium sulfate and with urea, in a split application 60 and 75 days after sowing. An increase in the salinity of the water increased the salinity levels of soil, which was intensified by a dose of 150 mg of N, mainly when applied in the form of ammonium sulfate, inhibiting dry matter production and chlorophyll content in jackfruit seedlings. The greatest reductions in chlorophyll a and b content occurred in jackfruit seedlings irrigated with water of 4.0 dS m-1 conductivity in the soil without nitrogen fertilization. Urea is the most suitable nitrogen source for the production of seedlings under conditions of high salinity.

Irrigation with saline water is a worldwide necessity an excess of salts in water or in soil causes growth inhibition, and negatively affects the productivity of many crops. Application of nitrogen fertilizers may be a way of mitigating the effects of salts on plants. The aim of this study was to evaluate the accumulation of biomass and the chlorophyll pigment content in jackfruit seedlings irrigated with water of increasing salinity level in soil with nitrogen sources. The treatments were distributed in randomized blocks with four replicates and three plants per plot, arranged in a 5 × 3 factorial scheme, related to electrical conductivity levels of the irrigation water of 0.3, 1.0, 2.0, 3.0 and 4.0 dS m−1, in soil without nitrogen, with ammonium sulfate and with urea, in a split application 60 and 75 days after sowing. An increase in the salinity of the water increased the salinity levels of soil, which was intensified by a dose of 150 mg of N, mainly when applied in the form of ammonium sulfate, inhibiting dry matter production and chlorophyll content in jackfruit seedlings. The greatest reductions in chlorophyll a and b content occurred in jackfruit seedlings irrigated with water of 4.0 dS m−1 conductivity in the soil without nitrogen fertilization. Urea is the most suitable nitrogen source for the production of seedlings under conditions of high salinity. | A irrigação com água salina é uma necessidade mundial e o excesso de sais da água ou do solo, causa inibição no crescimento e no rendimento da grande maioria das plantas cultivadas. Nesse contexto, os fertilizantes nitrogenados podem constituir alternativa para a mitigação dos efeitos dos sais sobre as plantas. Com isso, objetivou-se avaliar o acúmulo de biomassa e o índice de pigmentos clorofiláticos em mudas de jaqueira irrigadas com água de salinidades crescentes no solo com fontes de nitrogênio. Os tratamentos foram distribuídos em blocos casualizados com quatro repetições e com três plantas por parcela, arranjados em fatorial 5 × 3, relativo aos níveis de condutividade elétrica da água de irrigação de 0,3; 1,0; 2,0; 3,0 e 4,0 dS m–1, no solo sem nitrogênio, com sulfato de amônio e com ureia aplicados parceladamente aos 60 e 75 dias após a semeadura. O aumento da salinidade da água elevou a salinidade do solo, a qual foi intensificada pela dose de 150 mg de N, principalmente quando aplicada na forma de sulfato de amônio, ao ponto de inibir a formação de massa da matéria seca e os teores de clorofila em mudas de jaqueira. As maiores reduções no índice de clorofila a e b foram nas mudas de jaqueira irrigadas com água de 4,0 dS m–1 no solo sem adubação nitrogenada. A ureia é a fonte nitrogenada mais indicada para produção de mudas em condições de elevada salinidade.

Irrigation with saline water is a worldwide necessity an excess of salts in water or in soil causes growth inhibition, and negatively affects the productivity of many crops. Application of nitrogen fertilizers may be a way of mitigating the effects of salts on plants. The aim of this study was to evaluate the accumulation of biomass and the chlorophyll pigment content in jackfruit seedlings irrigated with water of increasing salinity level in soil with nitrogen sources. The treatments were distributed in randomized blocks with four replicates and three plants per plot, arranged in a 5 × 3 factorial scheme, related to electrical conductivity levels of the irrigation water of 0.3, 1.0, 2.0, 3.0 and 4.0 dS m −1 , in soil without nitrogen, with ammonium sulfate and with urea, in a split application 60 and 75 days after sowing. An increase in the salinity of the water increased the salinity levels of soil, which was intensified by a dose of 150 mg of N, mainly when applied in the form of ammonium sulfate, inhibiting dry matter production and chlorophyll content in jackfruit seedlings. The greatest reductions in chlorophyll a and b content occurred in jackfruit seedlings irrigated with water of 4.0 dS m −1 conductivity in the soil without nitrogen fertilization. Urea is the most suitable nitrogen source for the production of seedlings under conditions of high salinity. | A irrigação com água salina é uma necessidade mundial e o excesso de sais da água ou do solo, causa inibição no crescimento e no rendimento da grande maioria das plantas cultivadas. Nesse contexto, os fertilizantes nitrogenados podem constituir alternativa para a mitigação dos efeitos dos sais sobre as plantas. Com isso, objetivou-se avaliar o acúmulo de biomassa e o índice de pigmentos clorofiláticos em mudas de jaqueira irrigadas com água de salinidades crescentes no solo com fontes de nitrogênio. Os tratamentos foram distribuídos em blocos casualizados com quatro repetições e com três plantas por parcela, arranjados em fatorial 5 × 3, relativo aos níveis de condutividade elétrica da água de irrigação de 0,3; 1,0; 2,0; 3,0 e 4,0 dS m –1 , no solo sem nitrogênio, com sulfato de amônio e com ureia aplicados parceladamente aos 60 e 75 dias após a semeadura. O aumento da salinidade da água elevou a salinidade do solo, a qual foi intensificada pela dose de 150 mg de N, principalmente quando aplicada na forma de sulfato de amônio, ao ponto de inibir a formação de massa da matéria seca e os teores de clorofila em mudas de jaqueira. As maiores reduções no índice de clorofila a e b foram nas mudas de jaqueira irrigadas com água de 4,0 dS m –1 no solo sem adubação nitrogenada. A ureia é a fonte nitrogenada mais indicada para produção de mudas em condições de elevada salinidade.

Vetiver grass is a member of the grass family Poaceae. Its fast development is probably due to the interaction with native microbiota, whose influence has not been studied yet. The objective of this work was to evaluate the colonization and development of the vetiver grass (Chrysopogon zizanioides (L.) Roberty) inoculated with arbuscular mycorrhizal fungi and dark septate endophytic fungi. The experimental design was a completely randomized design with six treatments (control, without mycorrhizal fungi, native inoculants, UFLA05 - Gigaspora albida, UFLA351 - Rhizoglomus clarum, UFLA372 - Claroideoglomus etunicatum, and UFLA401 - Acaulospora morrowiae), with three replicates each. Vetiver grass tillers as well as the native microbial inoculum were obtained from the Lower São Francisco river experimental area, located in Sergipe state, Northeastern Brazil. There was a negative interaction between all tested UFLAs mycorrhizal isolates and the native microbiota (mycorrhizal and endophytic fungi) in the treatments, especially when taking into consideration plant height and volume of roots. The effects of inoculation with UFLA isolates may have been influenced by the presence of the native mycorrhizal fungi and the dark septate endophytic fungi. Vetiver grass was responsive to the native inoculant. The mycorrhizal colonization of the vetiver grass was vesicular, but the formation of the arbuscules can be influenced by the interaction between the fungus, plant, and the environment.

Vetiver grass is a member of the grass family Poaceae. Its fast development is probably due to the interaction with native microbiota, whose influence has not been studied yet. The objective of this work was to evaluate the colonization and development of the vetiver grass (Chrysopogon zizanioides (L.) Roberty) inoculated with arbuscular mycorrhizal fungi and dark septate endophytic fungi. The experimental design was a completely randomized design with six treatments (control, without mycorrhizal fungi, native inoculants, UFLA05 – Gigaspora albida, UFLA351 – Rhizoglomus clarum, UFLA372 – Claroideoglomus etunicatum, and UFLA401 – Acaulospora morrowiae), with three replicates each. Vetiver grass tillers as well as the native microbial inoculum were obtained from the Lower São Francisco river experimental area, located in Sergipe state, Northeastern Brazil. There was a negative interaction between all tested UFLAs mycorrhizal isolates and the native microbiota (mycorrhizal and endophytic fungi) in the treatments, especially when taking into consideration plant height and volume of roots. The effects of inoculation with UFLA isolates may have been influenced by the presence of the native mycorrhizal fungi and the dark septate endophytic fungi. Vetiver grass was responsive to the native inoculant. The mycorrhizal colonization of the vetiver grass was vesicular, but the formation of the arbuscules can be influenced by the interaction between the fungus, plant, and the environment. | O capim vetiver é uma espécie da família poácea que apresenta rápido desenvolvimento, provavelmente decorrente da interação com a microbiota nativa, cuja influência ainda não foi estudada. O objetivo deste trabalho foi avaliar a colonização e o desenvolvimento do capim vetiver inoculado com fungos micorrízicos arbusculares e fungos endofíticos “dark septate”. O delineamento experimental utilizado foi inteiramente casualizado composto por seis tratamentos (controle sem fungo micorrízico; inoculante microbiano nativo; UFLA05 - Gigaspora albida, UFLA351 – Rhizoglomus clarum, UFLA372 – Claroideoglomus etunicatum e UFLA401 – Acaulospora morrowiae), com três repetições. Os perfilhos de capim vetiver, assim como o inóculo microbiano nativo foram obtidos na área experimental do Baixo São Francisco, localizado no Estado de Sergipe, Nordeste do Brasil. O efeito da inoculação dos isolados UFLAs pode ter sido influenciado pela presença da micorriza nativa e pelos fungos endofíticos “dark septate”. Houve uma interação negativa entre todos isolados UFLAs testados e a microbiota nativa (micorriza e endofítico), nos tratamentos, principalmente quando se considera a altura da planta e o volume de raízes. O capim vetiver foi responsivo ao inoculante microbiano nativo. A colonização micorrízica do capim vetiver foi vesicular, mas a formação dos arbúsculos pode ser influenciada pela interação fungo, planta e ambiente.

Plasma technology is a fast, cost-effective, and pollution-free method that can be used in place of conventional methods to overcome seed dormancy. The goal of the present study was to determine the effect of different application times of atmospheric plasma on soaking and germination of Hybanthus calceolaria seeds in order to accelerate these processes. Helium plasma jet produced by dielectric barrier discharge was used to treat H. calceolaria seeds with applications of 1, 5, and 10 minutes. The treated seeds were characterized considering their weight variation during soaking, changes in electrical conductivity, and pH. It was found that germination depended on the plasma application time. The treatment of H. calceolaria seeds with atmospheric plasma for 1 minute provided 3.5 times greater germination in comparison to untreated seeds. Atmospheric plasma technology obtained by dielectric barrier discharge had potential of being used as a germination accelerant in H. calceolaria seeds. The treatment of H. calceolaria seeds using atmospheric plasma for 1 minute favored germination.

Plasma technology is a fast, cost-effective, and pollution-free method that can be used in place of conventional methods to overcome seed dormancy. The goal of the present study was to determine the effect of different application times of atmospheric plasma on soaking and germination of Hybanthus calceolaria seeds in order to accelerate these processes. Helium plasma jet produced by dielectric barrier discharge was used to treat H. calceolaria seeds with applications of 1, 5, and 10 minutes. The treated seeds were characterized considering their weight variation during soaking, changes in electrical conductivity, and pH. It was found that germination depended on the plasma application time. The treatment of H. calceolaria seeds with atmospheric plasma for 1 minute provided 3.5 times greater germination in comparison to untreated seeds. Atmospheric plasma technology obtained by dielectric barrier discharge had potential of being used as a germination accelerant in H. calceolaria seeds. The treatment of H. calceolaria seeds using atmospheric plasma for 1 minute favored germination. | A tecnologia de plasma constitui-se em um método rápido, econômico e livre de poluição que pode ser utilizada na superação de dormência de sementes em substituição aos métodos convencionais. O objetivo com esse estudo foi verificar o efeito do tempo de aplicação de plasma atmosférico sobre a embebição e germinação de sementes de Hybanthus calceolaria visando à aceleração destes processos. Jato de plasma de gás hélio, produzido por descarga em barreira dielétrica (DBD), foi utilizado para tratar as sementes de H. calceolaria por 1, 5 e 10 minutos de aplicação. As sementes tratadas foram caracterizadas quanto à variação de peso durante a embebição, variações da condutividade elétrica e pH. Verificou-se que a germinação depende do tempo de aplicação do plasma. O tratamento de sementes de H. calceolaria com plasma atmosférico por 1 min. proporcionou incremento na germinação de 3,5 vezes em comparação com as não tratadas. A tecnologia de plasma atmosférico, obtido por barreira dielétrica, apresenta potencial de utilização como acelerador da germinação de sementes de H. calceolaria. O tratamento de sementes de H. calceolaria à plasma atmosférico durante 1 minuto favorece a germinação.