Pingo De Research Articles

Modulation of Drought-Induced Stress in Cowpea Genotypes Using Exogenous Salicylic Acid.

Plant endogenous mechanisms are not always sufficient enough to mitigate drought stress, therefore, the exogenous application of elicitors, such as salicylic acid, is necessary. In this study, we assessed the mitigating action of salicylic acid (SA) in cowpea genotypes under drought conditions. An experiment was conducted with two cowpea genotypes and six treatments of drought stress and salicylic acid (T1 = Control, T2 = drought stress (stress), T3 = stress + 0.1 mM of SA, T4 = stress + 0.5 mM of SA, T5 = stress + 1.0 mM of SA, and T6 = stress + 2.0 mM of SA). Plants were evaluated in areas of leaf area, stomatal conductance, photosynthesis, proline content, the activity of antioxidant enzymes, and dry grain production. Drought stress reduces the leaf area, stomatal conductance, photosynthesis, and, consequently, the production of both cowpea genotypes. The growth and production of the BRS Paraguaçu genotype outcompetes the Pingo de Ouro-1-2 genotype, regardless of the stress conditions. The exogenous application of 0.5 mM salicylic acid to cowpea leaves increases SOD activity, decreases CAT activity, and improves the production of both genotypes. The application of 0.5 mM of salicylic acid mitigates drought stress in the cowpea genotype, and the BRS Paraguaçu genotype is more tolerant to drought stress.

Biological method of single-node cuttings for budburst in five fig cultivars subjected to artificial chilling

Fig orchard expansion requires knowledge of the thermal requirements of genotypes available in different climatic regions. The budburst of fig cultivars was assessed by biological single-node cutting and exposure to artificial chilling. Cuttings from five cultivars were collected during two crop seasons, subsequently packaged in a horizontal position in a cold chamber (8 ± 0.5ºC), and artificially chilled for 0, 40, 80, 120, and 160h. Cuttings were preserved under controlled conditions (23 ± 1°C, RH 85%, and 16h photoperiod). The variables evaluated were the budding velocity, average time and final rate of sprouting, vigorous shoot rate, and average time to leaf opening. The single-node cutting test allowed the assessment of dormancy, which is influenced by the accumulation of chilling in each crop season. The average time and final budding rate varied depending on the temperature requirements for budding. The cultivars were classified on an increasing scale according to their chilling requirements as follows: Pingo de Mel < Roxo de Valinhos < Brown Turkey < White Genova < Troyano. The traditional cultivar in Brazil is Roxo de Valinhos, but all of the cultivars studied had the potential to diversify the fig orchards in this region.

Chilling and forcing requirement of five international fig cultivars grown in Southeastern Brazil

Chill hours availability influence break dormancy, sprouting and production of temperate fruits trees in different regions. However, there are few reports on the subject for fig tree. This study aimed to evaluate the effects of the accumulated chilling hours on the physiology and dormancy release of fig cultivars. Stem cuttings of five fig cultivars were collected at the end of winter over two crop cycles and exposed to 0, 40, 80, 120 and 160 accumulated chilling hours (CH) in a cold chamber (8±0.5 ºC). Physiology of fig buds was then evaluated with regards to antioxidant enzymes activity, carbohydrate and nitrogen contents. The exposure of fig stem cuttings with two buds to different accumulated CH presented physiological changes for antioxidant enzymes activity, carbohydrates and nitrogen contents and confirming that the cultivars responded differently to the climatic conditions of each crop cycle. Results detected that the lowest accumulated CH in field in 2018 (2.7 CH) enabled a greater effect of the artificial CH when compared to 2017 (19.5 CH). Each fig cultivar had a critical accumulation point. The cultivars Roxo de Valinhos and Pingo de Mel require less CH to break dormancy, while Troyano requires more CH to finish this vegetative rest period.

Photosynthetic Responses, Growth, Production, and Tolerance of Traditional Varieties of Cowpea under Salt Stress.

HighlightsSalinity tolerance among traditional varieties of cowpea is variable.High net photosynthesis is observed in cowpea-tolerant varieties under salt stress.The decrease in photosynthesis is caused by stomatal restriction and low photochemical efficiency.Cowpea varieties are similar in photochemical efficiency and photochemical quenching.The decrease in pod number and seeds per pod are the main effects of salinity on cowpea production.Cowpea is the main subsistence crop—protein source—for the Brazilian semi-arid region. The use of salt-stress-tolerant varieties can improve crop yields. We evaluated the effect of irrigation with brackish water on the growth, photosynthetic responses, production, and tolerance of fifteen traditional varieties of cowpea. The experiment was conducted in randomized blocks, in a 15 × 2 factorial scheme, composed of 15 traditional varieties of cowpea and two salinity levels of irrigation water (0.5 and 4.5 dS m−1), with five replicates. Plants were grown in pots containing 10 dm3 of soil for 80 days. The reduction in the photosynthetic rate of cowpea varieties occurs mainly due to the decrease in stomatal conductance caused by salt stress. Salt stress increased the electron transport rate and photochemical quenching of cowpea varieties, but stress-tolerant varieties increased the CO2 assimilation rate and instantaneous carboxylation efficiency. The Ceará, Costela de Vaca, Pingo de Ouro, Ovo de Peru, and Sempre Verde varieties are tolerant to salt stress. Salt stress decreases 26% of the production of tolerant varieties to salt stress and 54% of susceptible varieties. The present findings show the existence of variability for saline stress tolerance in traditional varieties of cowpea and that Ceará, Costela de Vaca, Pingo de Ouro, and Ovo de Peru varieties are more suitable for crops irrigated with saline water.

Performance of cowpea weevil Callosobruchus maculatus (F.) infesting seeds of different Vigna unguiculata (L.) Walpers genotypes: The association between bruchid resistance and chitin binding proteins

Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae) is an important pest of stored cowpea seeds (Vigna unguiculata) (L.) Walpers and the infestation of these seeds by the pest is a limitation to their production. Many studies have identified V. unguiculata genotypes that were resistant to the insect infestation. These resistant genotypes can lead to a reduction on the use of insecticides, avoiding environmental and food contamination. In this work, we evaluated the resistance or susceptibility of different V. unguiculata genotypes to infestation by C. maculatus. Our results showed that the number of eggs laid by C. maculatus varied from 6 to 13 eggs per seed among genotypes. Almost all the eggs were viable, and the larvae hatched at 5 days after oviposition (DAO). Larval survival was decreased in some genotypes, where only about 40% of the larvae survived. The mass of the larvae at 20 DAO ranged from 8.8 mg to 6.4 mg/larva. The emergence of adults was also decreased in some genotypes. The seed mass consumed by the larvae varied between 40 and 70% and affected seed germinability. Proteins similar to vicilins, glycinin, and CPRD22 were identified in V. unguiculata Pingo de Ouro 1-5-4 and MNC06-909-76 lines. Chitin-binding proteins were isolated from some genotypes and were toxic to the larvae at 1%. The docking of vicilin with chitin [(NAG)4] showed negative value of affinity energy, indicating a spontaneous binding. The vicilin interacted with (NAG)4 by hydrogen bonds, saline bridge, and hydrophobic interactions. These results suggest that part of the interference in the insect development, observed in some cowpea genotypes, may be due to the presence of chitin-binding vicilins.

Composite Coatings of Chitosan and Alginate Emulsions with Olive Oil to Enhance Postharvest Quality and Shelf Life of Fresh Figs (Ficus carica L. cv. 'Pingo De Mel').

Fresh figs are very appreciated and have been associated with health benefits. However, these fruits are highly perishable. In this study, edible coatings were studied envisaging their positive effect in enhancing figs’ shelf-life. Fig fruits cv. ‘Pingo de mel’ were harvested at commercial ripening stage and single emulsion-based coatings, composed of chitosan + olive oil and alginate + olive oil, were applied. After coatings application by dipping each fruit in the emulsion-based solutions at 4 °C and drying, the coated fruits were sprayed with crosslinking solutions (6% tripolyphosphate and 1% calcium chloride for chitosan and alginate-based coatings, respectively). Then, were maintained at 4 °C and analyzed after 1, 7, 14 and 19 days of storage. After each time interval, fruits were further maintained at 25 °C for 2 days. The results have shown that coatings were effective on delaying fungal decay and postharvest ripening indicators (respiration rate, mass loss, softening and total soluble solids/titratable acidity ratio). The results foresee a fruits’ shelf life between 14 and 19 days under refrigeration at 4 °C that may be followed up to 2 days at ambient temperature, higher than that estimated for uncoated fruits (less than 14 days at 4 °C plus to 2 days at ambient temperature).

Tolerance of seedlings traditional varieties of cowpea (Vigna unguiculata) to salt stress

Cowpea is an important source of protein, being the main subsistence crop in the northeast region of Brazil, where water restriction and salinity are limiting factors. Identification of saline stress tolerant varieties can aid crop expansion and improve crop yields. The objective was to study the tolerance of traditional varieties of cowpea to the salinity of irrigation water in the emergency and initial growth phase. The experiment was carried out in a greenhouse using a completely randomized design (DIC), in a 23 x 2 factorial scheme, composed of 23 cowpea varieties (Canapu Vermelho, Boquinha, Pingo de Ouro, Sempre Verde, Ceará, Baeta, Manteiga, Roxão, Costela de Vaca, Feijão Branco, Coruja, Rabo de Peba Branco, Sopinha, Canapu Branco, Lisão, Canapu Miúdo, Sempre Verde Ligeiro, Vagem Roxa, Ovo de Peru, Rabo de Peba Miúdo, Feijão Azul, Canário, and Paulistinha) and two levels of salinity of irrigation water (S1 = 0.5 and S2 = 5.5 dS m-1), with four repetitions of 50 seeds. The seedlings were evaluated for emergence, vigor, salinity tolerance index, and dissimilarity. Increased salinity of irrigation water reduced emergence, vigor and dry matter accumulation of cowpea varieties. The cowpea varieties ‘Lisão’, ‘Costela de Vaca’, ‘Canário’, ‘Feijão Branco’, ‘Ceará’, and ‘Boquinha’ are the most tolerant to salinity, while the varieties ‘Sempre Verde’ and ‘Manteiga’ are the most sensitive to salinity in the emergency and initial growth phase.

Conduction systems in fig tree with two cultivars, evaluating fruits quality and yield

The fig tree is rustic and one of the fruit species with great economic importance, because it adapts easily to different climate and soil types. The objective of this study was to evaluate the influence the branches number and the fig tree cultivar on yield and fruit quality. The orchard implanted with two cultivars, Roxo de Valinhos and Pingo de Mel, and conducted with different numbers of productive branches, being: 16, 24 and 32. The utilized lineation was completely randomized, with three replicates, each replicate being composed of four plants. The analyzed variables were: branches length (cm), number of fruits per plant, number of fruits per branch meter, yield of mature fruits (Kg ha-1), yield of green fruits (Kg ha-1), accumulated productivity (Kg ha-1), fruit size (cm3), average fruit weight (g), soluble solids (°Brix) and fruit dry matter (%). The daily elongation rate and the mean length of the branches did not influence the different treatments. For productivity, noticed superiority on cultivar Roxo de Valinhos, with the higher the number of productive branches in the plants. Fruit quality, relative to soluble solids and dry matter, also did not influence the treatments. Fruits in larger caliber and size found from plants of the cultivar Roxo de Valinhos. Both for the production of fruits for fresh consumption and for the industrialization it is recommended the conduction with greater number of productive branches being between 24 and 32, for the greater productive yield.

Physical and biometric characterization of jabuticaba variety 'Pingo De Mel' oriunda of cerrado goiano

The biometric and physical characterization can provide information on format, yield, concentration of soluble solids. The objective was to characterize physically and biometrically the jabuticaba variety 'Pingo de mel' from the cerrado of Goiás. 200 jaboticaba were used. The content of total soluble solids, longitudinal and transverse diameters, total mass, volume, shape index, density, yield of peeled pulp and the thickness of the peeled pulp were determined. The total soluble solids 15,16 ° Brix, soluble solids content is one of the most important tools to estimate fruit quality. The longitudinal and transverse diameter was 22.25 and 21.56 mm, respectively. The total mass had an average variation because the coefficient of variation was above 20%. Variations can occur due to cultivation techniques and climate can be related to this also variations presented for the volume of this fruit. As for the format index, the fruit was classified as round. The density was 8.35 g mL -1, yield and pulp thickness were already high. Samples of total soluble solids and yield are parameters used as control and selection by the food industry, it means that the fruits in evaluation presented good potential of industrial processing.

Genetic parameters related to gas exchange and production components in cowpea populations under drought

Drought is the main abiotic stress in many crops which is affected by the high number of genes involved and intense genotype × environment interactions. However, gas exchange represents a new approach with a high detection efficiency. This study aims to evaluate genetic parameters; determine population performances based on data linked to gas exchange and production components; and determine whether gas exchange is useful for selecting Vigna unguiculata populations that are drought tolerant using six populations from crosses between BR3-Tracuateua (sensitive to drought) and Pingo de ouro-1–2 (drought-tolerant). Our results revealed that production components, mainly grain production, water-use efficiency and carboxylation instantaneous efficiency, and gas exchange presented higher means and variances in the F2 generation. In general, the additive variances were higher than the dominance variances, suggesting intense additive allelic interactions for the evaluated characteristics. Gas exchange is efficient for selecting cowpea populations with tolerance to drought because they present high correlation coefficients with production components, such as between grain production and the carboxylation instantaneous efficiency (0.91), as well as grain production and water-use efficiency (0.89).

Bioactive compounds and antioxidant activity of jabuticaba var. Pingo de mel during its physiological development

ABSTRACT The bioactive compounds and in vitro antioxidant activity of jabuticaba fruits var. Pingo de mel were evaluated during their physiological development. The fruits were harvested ten days after anthesis until maturity, at intervals of four days between collections. The period between anthesis and maturity was 34 days. Higher phenolics levels, hydrolysed tannins, and antioxidant activity were observed in 10 days after anthesis, while vitamin C contents were higher throughout the ripening process. At the end of development (34 days), higher levels of vitamin C and lower hydrolysed tannin were observed. It is known that the lower the hydrolysed tannins, the better the sensory characteristics of the fruit, and considering the benefits of vitamin C, it is necessary to harvest the jabuticaba fruits var. Pingo de mel in 34 days after anthesis for better use of these compounds.

Chlorophyll fluorescence as a tool to select salinity-tolerant cowpea genotypes

The use of saline water reduces the growth and productivity of crops, so the need for techniques that make possible the use of this resource such as the use of salinity tolerant genotypes and efficient selection methods are of great importance. Thus, this study aimed to evaluate the tolerance of cowpea (Vigna unguiculata L. Walp.) genotypes to salt stress, through the chlorophyll fluorescence analysis. The experiment was conducted in a protected environment at the Federal University of Campina Grande, Paraíba, Brazil, using a completely randomized design in a 2 x 10 factorial arrangement, with three replications, consisting of two levels of irrigation water salinity (0.6 and 5.1 dS m-1) and ten cowpea genotypes: (G1: MNCO1-649F-2-1, G2: MNCO3-736F-2, G3: PINGO DE OURO-1-2, G4: BRS GURGUÉIA, G5: BRS MARATAOÃ, G6: MNCO2-676F-3, G7: MNCO2-683F-1, G8: MNCO3-737F-5-4, G9: MNCO3-737F-5-9, and G10: BRS TUMUCUMAQUE). The stem length, stem diameter, SPAD index, and chlorophyll fluorescence transients were evaluated. The G2 and G4 genotypes had the lowest reductions in the growth, stem diameter, initial fluorescence, and primary and maximum photochemical efficiency of PSII, proving to be tolerant to salinity. Chlorophyll fluorescence is a tool that can be used in the selection of salinity-tolerant cowpea genotypes.

Nutritional, chemical and bioactive profiles of different parts of a Portuguese common fig (Ficus carica L.) variety.

This study aims to give an unprecedented contribution on the chemical composition and bioactivities of the most produced and appreciated Portuguese fig variety ("Pingo de Mel") with the view of expanding the knowledge on its potentialities. An advanced characterization of its peel and pulp parts was carried out. Four free sugars (glucose, fructose, trehalose and sucrose), 5 organic acids (oxalic, quinic, malic, citric, and succinic acids), tocopherols in all their 4 forms, besides 23 fatty acids were detected in the samples. Fifteen different phenolic components were found in the peel hydroethanolic extract; whereas 12 were detected in the pulp hydroethanolic extract. Quercetin-3-O-rutinoside (rutin) was the major constituent of the peel, accounting for 33.8% of its phenolic content, followed by 5-O-caffeoylquinic acid and vanillic acid malonyl di-deoxyhexoside. Caffeic acid derivatives, such as caffeic acid hexosides, were the major components of pulp, followed by vanillic acid derivatives and O-caffeoylquinic acid. Both extracts displayed promising antioxidant capacities in all methods used, namely the 2,2-diphenyl-1-picrylhydrazyl radical-scavenging, the reducing power, the inhibition of β-carotene bleaching assays, the thiobarbituric acid reactive substances assay and the oxidative haemolysis inhibition assay; however, the peel presented significantly lower IC50 values than pulp. The extracts showed practically identical antibacterial capacities, being effective against methicillin-sensitive Staphylococcus aureus (MICs = 2.5 mg/mL), besides methicillin-resistant S. aureus, Escherichia coli and Morganella morganii (MICs = 5 mg/mL). The obtained results evidence that the fig peel is superior to the corresponding pulp as it relates to nutritional and phenolic profiles as well as bioactivities, endorsing the urgency in valorising and exploiting this usually discarded industrial by-product.

Efficiency in the use of phosphorus by cowpea genotypes

Cowpea (Vigna unguiculata (L.) Walp.) is an edible legume with good ability to fix nitrogen and not demanding soil fertility. However, some genotypes may have a greater ability to utilize the nutrients available in the soil for their growth. Thus, the objective of this work was to evaluate the efficiency of phosphorus (P) use in genotypes of cowpea. The experiment was conducted in the field and the experimental design was a randomized complete block design with four replicates arranged in a 2 x 5 factorial scheme. The treatments consisted of two P doses (0 and 60 kg ha-1 of P2O5) and five bean genotypes (Paulistinha, BRS Xiquexique, Pingo de Ouro, Corujinha, and Costela de Vaca). Each plot was formed by four plant rows, measuring 3.0 m in length, spaced 1.0 x 0.3 m, and with two plants per hole. The genotypes responded significantly to the increase in P levels in the soil, with increases in the number of seeds per pod, number of pods per plant, productivity, dry mass, and plant P accumulation. "BRS Xiquexique" was efficient and responsive, and it could be indicated as the most appropriate for cultivation in the region. "Corujinha" is the most suitable cultivar for production in high levels of P among the creole genotypes evaluated. "Costela de Vaca" and "Paulistinha" can be indicated for low P production in the soil. low P production.

Effect of the addition of calcium chloride and different storage temperatures on the post-harvest of jabuticaba variety Pingo de Mel

Abstract The objective of this study was to analyze the effect of different calcium chloride concentrations on the post-harvest conservation of jabuticaba variety Pingo de Mel at different storage temperatures. The fruit were collected 30 days after the anthesis and subjected to immersions in calcium chloride solution at different concentrations (0%, 2%, 4%, and 6%) for 30 minutes at room temperature. Then, the fruit were dried and packed in polypropylene bags and incubated in a chamber at different temperatures (6 °C, 12 °C, and 25 °C). Samples were analyzed at time 0 and every two days, up to 12 days of storage. No effect of different calcium chloride concentrations was observed in the fruit characteristics at different storage temperatures over time. During storage, an increase of soluble and total pectin contents, antioxidant activity, CO2, total sugars, acidity, and weight loss was observed. Higher storage temperatures affected both the increase in weight loss, pH, and O2 production and the reduction of vitamin C content. Refrigeration was important for the post-harvest conservation of jabuticaba variety Pingo de Mel , once the fruit stored at 6 °C suffered minor variations with improvements or little changes during the 12 days.

Physiological and Sanitary Quality in Cowpea Seeds Produced in Rio Grande Do Norte, Brazil

The importance of cowpea (Vigna unguiculata (L.) Walp.) to the Northeast region of Brazil is undeniable, it is a major crop in local family agriculture. As a result, the research aimed to evaluate the physiological and sanitary quality of local varieties of cowpea coming from the state of Rio Grande do Norte. The experiment was carried out at the Seed Pathology and Seed Analysis Laboratory, in Federal University of Paraíba, Campus II, Areia, Paraiba, Brazil. Six cowpea varieties (Baeta, Coruja, Sempre Verde, Epace 10, Feijão da Bahia and Pingo de Ouro) from rural Area of the municipality of Apodi, Rio Grande do Norte, Brazil.were evaluated  Seed physiological quality was evaluated by determining the first germination count (FGC), germination percentage (G%), seedling length (SL) and electrical conductivity (EC). The sanitary quality of the seeds was evaluated by the method of incubation in filter paper (blotter test). The experimental design was completely randomized, with 4 replicates. The Pingo de Ouro, Sempre Verde and Coruja varieties had germination percentages greater than the minimum standards required for commercialization, while the lower germination percentage and vigor of the Feijão da Bahia, Epace 10 and Baeta varieties may be associated with the presence of Aspergillus sp. and Penicillium sp.

Potential of figs from cultivars grown in subtropical regions for canning purposes

Abstract: The objective of this work was to evaluate the influence of fig (Ficus carica) cultivars grown in subtropical regions on the physicochemical, rheological, and sensorial characteristics of the canned figs. Fresh fruits of the cultivars were analyzed for length, diameter, unit mass, total soluble solids, total titratable acidity, pH, total soluble solids/total titratable acidity ratio, and color. Canned figs were evaluated for titratable acidity, pH, color, texture profile, and sensory characteristics. The different physicochemical characteristics of the fresh figs influenced those of the obtained canned fruits. The canned figs from 'Lemon' and 'Pingo de Mel' presented the lowest and highest pH, respectively, whereas those from 'Troiano' showed the highest total titratable acidity. As for color, after processing, the canned figs, in general, presented a more greenish and darker color than the fresh fruits. The canned figs from 'Brunswick' and 'Troiano' had the lowest acceptance, whereas those from 'Bêbera Branca' and 'Roxo de Valinhos', the greatest. Less acid and softer canned figs are more widely accepted, which can be obtained from all cultivars, except from Brunswick and Troiano.

Proximate composition, minerals profile, and predominant sugars by ion chromatograph along the physiological development of jabuticaba var. Pingo de mel

Proximate composition, minerals profile, and predominant sugars by ion chromatograph along the physiological development of jabuticaba var. Pingo de mel

Yield of ‘Pingo de Ouro’ Cowpea Bean Under Different Sowing Densities and Goat Manure Doses in the Region of Mossoró, Brazil

Using goat manure may substantially increase cowpea bean productivity. This study evaluated the yield of ‘pingo de ouro’ cowpea bean under different sowing densities and goat doses in the region of Mossoró, Brazil. The experiment was conducted from October to December 2016 at the Experimental Farm Rafael Fernandes, Mossoró-RN, Brazil. Treatments arranged in two-way factorial with four goat manure doses (0.0, 0.5, 1 and 2 kg m-1), and two sowing densities of bean (75,000 and 37,500 plants ha-1), with three replicates. The experiment was performed in complete randomized blocks design. We evaluated the number and length of pods per plant, number of seed per pod, weight of 100 dry grains and dry grain yield. Higher grain yield occurred using 2.0 kg m-1 of goat manure (1,162.4 kg ha-1 or 234 kg 2,000 m-2) and 75,000 plants ha-1 (693.4 kg ha-1 or 138.6 kg 2,000 m-2). High sowing density in combination with goat manure is an affective.

Harvesting period of jabuticaba fruits var. ‘Pingo de Mel’ in relation to the physicochemical characterization evaluated during their development

The objective was to physically and chemically characterize jabuticaba fruits var. ‘Pingo de Mel’ during their development. Some fruits were harvested ten days after flowering (DAF) and harvesting was continued at four day intervals until the fruits were completely ripe (34 days). It was shown that the values for the diameter, mass, soluble solids and anthocyanins increased up to 30 DAF, whereas the soluble pectin content and ratio (relationship between soluble solids content and titratable acidity) increased up to 34 DAF. The respiratory rate showed the opposite behavior, reducing up to 30 DAF, and the values for firmness and chlorophyll reduced up to 34 DAF. The pH and ratio reduced up to 18 DAF with a subsequent increase up to 34 DAF, whereas the acidity showed the opposite behavior. In order to obtain high quality fruits with respect to ripeness it is important to consider the soluble solids and anthocyanin contents, which the present study showed to be indicators of the best moment for harvesting, that is, 30 DAF.