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PHYSICAL, CHEMICAL AND MORPHOLOGICAL CHARACTERISTICS OF BANANA CULTIVARS DEPENDING ON MATURATION STAGES
2017
CÉSAR FERNANDES AQUINO | LUIZ CARLOS CHAMHUM SALOMÃO | PAULO ROBERTO CECON | DALMO LOPES DE SIQUEIRA | SÔNIA MACHADO ROCHA RIBEIRO
The objective of this work was to morphologically characterize 15 banana cultivars and assess the physical and chemical characteristics of their fruits at two maturation stages, unripe (pre-climacteric) and ripening. The plants were evaluated regarding their pseudostem height and diameter, petiole length, leaf blade length, width and length-to-width ratio. The cultivar Ouro had fruits with lower diameter, total length, market weight and fresh weight at both stages, and also firmer pulp when they were unripe. The cultivar Caru-Roxa had higher fresh fruit and pulp weights, and the cultivar Terrinha had the highest percentage of pulp dry weight percentage in unripe and ripe fruits. The cultivars Maçã and Ouro had higher pulp-to-peel ratio in unripe fruits. The ripe peels had lower fresh weight and thickness and higher dry weight percentage compared to unripe peels. The fruit peel of the cultivar Marmelo had the highest fresh weight at both stages. The cultivars Marmelo and Maçã had higher percentage of peel dry weight percentage at both stages. The unripe pulp had lower soluble solids. The titratable acidity in the pulp increased with ripening. The average plant height ranged from 2.25 to 6.15 m. The cultivars that had the largest pseudostem diameters had also the highest heights, except the Prata-Anã and Prata-Graúda. The cultivar and maturity stage influenced all the characteristics evaluated in fruits, except the total and market lengths, which did not vary with the ripening of fruits.
Mostrar más [+] Menos [-]FIRST RECORD OF Xanthopastis timais IN AMARYLLIS AND EFFECT OF SOURSOP EXTRACT ON LARVAL MORTALITY
2017
LÍGIA BROGLIO MICHELETTI | SÔNIA MARIA FORTI BROGLIO | EURICO EDUARDO PINTO DE LEMOS | ROSEANE CRISTINA PREDES TRINDADE | ELLEN CARINE NEVES VALENTE
The aim of this study was to report the occurrence of Xanthopastis timais (Cramer, 1780) (Lepidoptera: Noctuidae) in amaryllis ( Hippeastrum hybridum Hort ., Amaryllidaceae), as well as estimating lethal concentrations (LC 50 and LC 99 ) of soursop seed extract, Annona muricata L. (Annonaceae), against its larvae. The experiment was carried out at the Laboratory of Entomology of the Research Center for Agricultural Sciences, Federal University of Alagoas, in Rio Largo - AL, Brazil . First, we collected caterpillars from amaryllis plants that were reared until pupal and adult stages (parental generation). Next, part of the adults was used for species identification, and the rest were bred to produce next generation (F1), being after that applied in a laboratory bioassay. The lab trial was performed in a completely randomized design, with six treatments and five replications containing three second - instar caterpillars. These larvae were fed pieces of amaryllis leaf (4 x 4 cm), which were previously soaked in treatments for 30 seconds and, air - dried on absorbent papers for one hour. Each treatment consisted of one concentration of ethanol extract of soursop seeds (0.0, 1.0, 0.5, 0.25, 0.125 and 0.0625% w/ v) with distilled water and DMSO at 1% (v/ v), for solutions. We noted that the lethal concentrations LC 50 and LC 99 were 0.29% (w/ v) and 2.27% (w/ v), respectively. In view of our results, we can state that larval stage of X . timais were influenced by extract application in terms of survival, mortality, larvae weight and larval stage length. Besides of that, it was the first time this species was recorded in Alagoas state.
Mostrar más [+] Menos [-]BUFFEL GRASS MORPHOAGRONOMIC CHARACTERIZATION FROM Cenchrus GERMPLASM ACTIVE BANK
2017
LEILA REGINA GOMES PASSOS BRUNO | RAFAELA PRISCILA ANTONIO | JOSÉ GERALDO DE AQUINO ASSIS | JOSÉ NILTON MOREIRA | IRLANE CRISTINE DE SOUZA ANDRADE LIRA
This study aimed to characterize buffel grass accessions of the Cenchrus Germplasm Active Bank (CGAB) from Embrapa Semi - Arid in a morphoagronomic way, checking the descriptors variability and efficiency in accessions on two consecutive cuts. Twenty - five accessions and five buffel grass cultivars were used in randomized complete block design with three replications. Evaluations were conducted after two consecutive cuts, each evaluation performed 90 days after each cut. Characterization was based on 15 quantitative and qualitative morphoagronomic descriptors. Quantitative descriptors were subjected to individual and joint univariate analysis of variance, followed by the Scott - Knott’s test at 5% significance. Yet qualitative descriptors were submitted to descriptive analysis. Both quantitative and qualitative descriptors were grouped based on the Gower algorithm for divergence analysis. A dendrogram and calculations of the characters relative importance for divergence were established. Genotype and cutting effects were significant for almost all descriptors in the joint analysis. This result indicates a genetic variability between genotypes and, regarding the cut, it indicates mainly differences in growth rate of each genotype in each cutting season. Genotypes were separated into three groups, which showed good genotype variation. The number of tillers per clump, followed by number of inflorescence and color of seeds, were the most relevant characters in genotype separation.
Mostrar más [+] Menos [-]IMPACT INJURY DIAGNOSIS IN MANGO THROUGH STARCH DEGRADATION INDEX
2017
FRANCISCO DE ASSIS DE SOUSA | RAILENE HÉRICA CARLOS ROCHA | INÁCIA DOS SANTOS MOREIRA | TÁDRIA CRISTIANE DE SOUSA FURTUNATO | JOSÉ FRANCIRALDO DE LIMA
This study aimed to evaluate the use of starch degradation index (SDI) in the diagnosis of areas of impact injuries in 'Tommy Atkins' mango, in different maturation stages. The experiment layout was a fully randomized factorial design (5 x 2), represented by five maturation stages and two handlings, with and without impact, with four replicates. SDI was determined through a subjective scale of scores indicating mango pulp darkened areas by reaction with iodine-potassium iodide solution. Subsequently, these scores were correlated with physicochemical quality variables. The results showed no influence of impact on fruit quality, in any of the studied maturation stages. Moreover, soluble solid contents increased throughout maturation stages, regardless of whether the fruits suffered impact or not. As a result, SDI is unsuitable to indicate fruit impact injury. However, there is a good correlation between SDI and pulp color, vitamin C, pH, titratable acidity, soluble solids, SS/ TA ratio and non-reducing sugars.
Mostrar más [+] Menos [-]PHYSIOLOGICAL RESPONSES OF DWARF COCONUT PLANTS UNDER WATER DEFICIT IN SALT - AFFECTED SOILS
2017
ALEXANDRE REUBER ALMEIDA DA SILVA | FRANCISCO MARCUS LIMA BEZERRA | CLAUDIVAN FEITOSA DE LACERDA | CARLOS HENRIQUE CARVALHO DE SOUSA | MARLOS ALVES BEZERRA
The objective of this study was to characterize the physiological acclimation responses of young plants of the dwarf coconut cultivar ̳Jiqui Green‘ associated with tolerance to conditions of multiple abiotic stresses (drought and soil salinity), acting either independently or in combination. The study was conducted under controlled conditions and evaluated the following parameters: leaf gas exchange, quantum yield of chlorophyll a fluorescence, and relative contents of total chlorophyll (SPAD index). The experiment was conducted under a randomized block experimental design, in a split plot arrangement. In the plots, plants were exposed to different levels of water stress, by imposing potential crop evapotranspiration replacement levels equivalent to 100%, 80%, 60%, 40%, and 20%, whereas in subplots, plants were exposed to different levels of soil salinity (1.72, 6.25, 25.80, and 40.70 dS m - 1 ). Physiological mechanisms were effectively limited when water deficit and salinity acted separately and/or together. Compared with soil salinity, water stress was more effective in reducing the measured physiological parameters. The magnitudes of the responses of plants to water supply and salinity depended on the intensity of stress and evaluation period. The physiological acclimation responses of plants were mainly related to stomatal regulation. The coconut tree has a number of physiological adjustment mechanisms that give the species partial tolerance to drought stress and/or salt, thereby enabling it to revegetate salinated areas, provided that its water requirements are at least partially met.
Mostrar más [+] Menos [-]CHEMICAL COMPOSITION AND TOXICITY OF CITRUS ESSENTIAL OILS ON Dysmicoccus brevipes (HEMIPTERA: PSEUDOCOCCIDAE)
2017
GISELE DOS SANTOS OLIVEIRA MARTINS | HUGO BOLSONI ZAGO | ADILSON VIDAL COSTA | LUIS MOREIRA DE ARAUJO | JOSÉ ROMÁRIO DE CARVALHO
The insect Dysmicoccus brevipes (Hemiptera: Pseudococcidae) has been reported as an important pest for several crops, especially coffee. The citrus essential oils can be obtained as by-products of the citrus-processing industry and have been tested as an alternative to control different insect groups. Therefore, the objective of this work was to determine the chemical composition and evaluate the toxicity of commercial sweet orange (Citrus sinensis), bitter orange (Citrus aurantium) and Sicilian lemon (Citrus limon) essential oils and pure monoterpene D-limonene on D. brevipes. The essential oils were analyzed by gas chromatography. Two bioassays were conducted; the first assessing the insect mortality in all oils and the second assessing the lethal concentrations (LC50 and LC95) of the most effective oils. The main components of the oils were D-limonene (83.33%) and Linalool (8.91%) (sweet orange); D-limonene (78.53%) and γ-terpinene (12.65%) (bitter orange); D-limonene (59.78%), beta-pinene (14.71%) and γ-terpinene (10.19%) (Sicilian lemon) and the compound D-limonene had 97% of purity. The highest mortalities were found with the use of the Sicilian lemon (98.68%) and sweet orange (94.11%)oils. The sweet orange oil presented lethal concentrations at 2.21% (LC50) and 3.55% (LC95), and the Sicilian lemon oil at 0.72% (LC50) and 2.91% (LC95). The main component of the sweet orange and Sicilian lemon essential oils was the D-limonene, and the Sicilian lemon oil was most effective oil to control D. brevipes.
Mostrar más [+] Menos [-]PHOSPHATE AND POTASSIUM FERTILIZATION FOR RADISH GROWN IN A LATOSOL WITH A HIGH CONTENT OF THESE NUTRIENTS
2017
ARTHUR BERNARDES CECÍLIO FILHO | ALEXSON FILGUEIRAS DUTRA | GILSON SILVERIO DA SILVA
The intensive cultivation of vegetables with frequent chemical fertilization may cause accumulation of nutrients in the soil. This, in turn, may reduce crop yields and damage the environment due to contamination of ground water and rivers. Thus, to increase the effects of P (0, 100, 200, 300 and 400 kg ha - 1 of P 2 O 5 ) and K (0, 60, 120, 180 and 240 kg ha - 1 of K 2 O) doses on the growth and productivity of radish cultivars (Sakata 19 and Sakata 25) in a soil with high levels of these nutrients, two experiments were conducted in randomized blocks with the factors cultivars and doses arranged in a 2 x 5 factorial design with three replications. Number of leaves per plant, leaf area, shoot and root dry mass, total and commercial productivity, percentage of cracked roots and P and K contents in the plant and in the soil were evaluated. The Sakata 19 cultivar performed better than the Sakata 25 in both experiments. The fertilization with P or K did not influence the growth and the productivity of both radish cultivars. Therefore, both cultivars of radish evaluated do not need to be fertilized with P and K when planted in a Latosol with high levels of these nutrients.
Mostrar más [+] Menos [-]FAMES AND MICROBIAL ACTIVITIES INVOLVED IN THE SUPPRESSION OF CASSAVA ROOT ROT BY ORGANIC MATTER
2017
JÉSSICA MORAIS DA SILVA | ERIKA VALENTE DE MEDEIROS | GUSTAVO PEREIRA DUDA | JAMILLY ALVES DE BARROS | UEMESON JOSÉ DOS SANTOS
The incorporation of organic matter has been used to manage of diseases caused by soilborne pathogen, but there is a gap in the use of coffee residues on disease supressiveness. The objective of this study was to evaluate the effect of organic matter sources against cassava root rot caused by F. solani CFF109. Fertilization with coffee residue (CR), cattle manure (CM), earthworm excrements (EE) and goat manure (GM) resulted in suppression of cassava root rot. The treatments of CR and CM presented higher reduction in the cassava disease severity. There were changes in the soil microbial community structure by organic matter incorporation, mainly in total fungi and Gram-negative bacteria populations. The total organic carbon and magnesium are negatively associated with disease severity. The microbial quotient, alkaline and acid phosphatase activities were positively and the biomarker a-15:0 was negatively associated with disease severity. This study indicated that agro-industrial residues can be recycled for providing organic matter and nutrients with effect for management of plant diseases by suppressing soilborne pathogens. This is the first evidence that the industrial residue of coffee can be use in the management of cassava root rot, caused by F. solani.
Mostrar más [+] Menos [-]PRINCIPAL COMPONENTS OF THE INTENSITY OF SQUAMOUS ROT ON PRICKLY PEAR PLANTAT IONS IN THE SEMIARID REGION OF THE STATE OF PARAÍBA, BRAZIL
2017
ANNE EVELYNE FRANCO DE SOUZA | LUCIANA CORDEIRO DO NASCIMENTO | BRENO OLIVEIRA DE SOUZA
The aim of the present study was to identify fungal pathogens associated with prickly pear rot and the main components of squamous rot on plantations in the semiarid region of the state of Paraíba, Brazil. Pathogens were identified morphologically. The determination of the main components of squamous rot intensity was based on the incidence and severity of the disease. Fifteen genera of fungi were associated with rot, including Scytalidium sp., which was found on all plantations. The analyses indicated that relative humidity and rainfall favored the intensity of rot more than temperature. At least three pathogens were found to be associated with a high incidence of rot in prickly pear species in the semiarid region of the state of Paraíba, Brazil, but Scytalidium sp. was the most widely distributed. Moreover, the disease caused by this fungus intensifies and progresses under conditions of high humidity at moderate temperatures.
Mostrar más [+] Menos [-]VERMICOMPOST APPLICATION IMPROVING SEMIARID-GROWN CORN GREEN EAR AND GRAIN YIELDS
2017
PAULO SÉRGIO LIMA E SILVA | PAULO IGOR BARBOSA E SILVA | VIANNEY REINALDO DE OLIVEIRA | FÁBIO HENRIQUE TAVARES DE OLIVEIRA | LUCAS RAMOS DA COSTA
Intensive corn farming quickly depletes soil organic matter in the nutrient-poor soils of the Brazilian semiarid region. Application of vermicompost, an excellent organic fertilizer, could help solve that problem. This study evaluated the effect of applying Eisenia fetida vermicompost in the seeding furrows, at 0, 2, 4, 6, 8, and 10 Mg.ha-1 application rates, on the green ear yield and grain yield of two corn cultivars. Treatments were replicated five times with split-plots (vermicompost application rates within plots) in a completely randomized block design. The number of mature ears, number of kernels per ear (cultivar BR 106), and 100-kernel weight (cultivar AG 1051) were not affected by vermicompost application rate. However, vermicompost application increased total number and weight of unhusked and husked marketable green ears as well as grain yield. Total number of green ears was higher in cultivar BR 106 than in cultivar AG 1051. Conversely, grain yield and total ear weight and marketable weight of unhusked and husked green ears was higher in cultivar AG 1051, but responses in the latter two traits were dose-dependent.
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