Deficiencies in postharvest technology and the attack of phytopathogens cause horticultural products, such as tomatoes to have a very short shelf life. In addition to the economic damage, this can also have negative effects on health and the environment. The objective of this work is to evaluate an active coating of sodium alginate in combination with eugenol-loaded polymeric nanocapsules (AL-NP-EUG) to improve the shelf life of tomato. Using the nanoprecipitation technique, NPs with a size of 171 nm, a polydispersity index of 0.113 and a zeta potential of −2.47 mV were obtained. Using the HS-SPME technique with GC-FID, an encapsulation efficiency percentage of 31.85% was determined for EUG. The shelf-life study showed that the AL-NP-EUG-treated tomatoes maintained firmness longer than those without the coating. In addition, the pathogenicity test showed that tomatoes with AL-NP-EUG showed no signs of damage caused by the phytopathogen Colletotrichum gloesporoides. It was concluded that the formulation of EUG nanoencapsulated and incorporated into the edible coating presents high potential for its application as a natural nanoconservative of fruit and vegetable products such as tomato.
The performance of five cauliflower cultivars in conventional and alternative phytosanitary management—without the use of synthetic pesticides—was evaluated. Two experiments were conducted at Epagri, Ituporanga Experimental Station in February 2018 and 2019. A randomized block design with four repetitions was adopted, with twenty plants of each cultivar as plots. The seedlings were transplanted on millet and mucuna straw at a spacing of 0.5 m × 0.8 m. We evaluated agronomic yield, inflorescence quality, pest damage and plant diseases, especially bacterial and fungal rots. The cauliflower hybrids Vera, Verona and Serena stood out in productivity and quality, being the most indicated for sowing in off-season crops, in the Alto Vale do Itajaí region. The most productive cultivars were less damaged by bacterial diseases and defoliating caterpillars and without interference of whitefly infestation on yield. The results also reveal that it is possible to control pests and diseases with phytosanitary products of lower toxicity, i.e., with lower residues of synthetic pesticides.
The wide distribution of the common beech (Fagus sylvatica) in Europe reveals its great adaptation to diverse conditions of temperature and humidity. This interesting aspect explains the context of the main objective of this work: to carry out a dendroclimatic analysis of the species Fagus sylvatica in the Polaciones valley (Cantabria), an area of transition with environmental conditions from a characteristic Atlantic type to more Mediterranean, at the southern limit of its growth. The methodology developed is based on the analysis of 25 local chronologies of growth rings sampled at different altitudes along the valley, generating a reference chronology for the study area. Subsequently, the patterns of growth and response to climatic variations are estimated through the response and correlation function, and the most significant monthly variables in the annual growth of the species are obtained. Finally, these are introduced into a Geographic Information System (GIS) where they are cartographically modeled in the altitudinal gradient through multivariate analysis, taking into account the different geographic and topographic variables that influence the zonal variability of the species response. The results of the analyses and cartographic models show which variables are most determinant in the annual growth of the species and the distribution of its climatic response according to the variables considered.
Urban trees are one of the valuable storage in metropolitan areas. Nowadays, a particular attention is paid to the trees and spends million dollars per year to their maintenance. Trees are often subjected to abiotic factors, such as fungi, bacteria, and insects, which lead to decline mechanical strength and wood properties. The objective of this study was to determine the potential degradation of Elm tree wood by Phellinus pomaceus fungi, and Biscogniauxia mediteranae endophyte. Biological decay tests were done according to EN 113 standard and impact bending test in accordance with ASTM-D256-04 standard. The results indicated that with longer incubation time, weight loss increased for both sapwood and heartwood. Fungal deterioration leads to changes in the impact bending. In order to manage street trees, knowing tree characteristics is very important and should be regularly monitored and evaluated in order to identify defects in the trees.
With the purpose of identifying the characteristics of variation in fruit size and seed production (potential and efficiency) of Cedrela odorata L. between sites and progenies established in the ejido La Balsa, municipality of Emiliano Zapata, Veracruz, fruits were harvested from 20 trees in February 2013, preserving the identity of each one. Fruit length and width were measured, seed was extracted and developed and aborted seeds were counted to calculate Seed Production Potential (SPP) and Seed Efficiency (SE). The results showed significant differences between sites and between progenies and for fruit length between sites. The mean values found were: 32.52 mm (fruit length), 18.73 mm (fruit width), 39.9 seeds per fruit (SPP) and 57.51% (SE). The seed of this species for its use should be selected taking into account the production characteristics of crops and outstanding individual trees, in addition, due to the current regulatory restrictions on seed collection, the establishment of trials and plantations for germplasm production is a viable option for forest management of the species.
Lettuce (Lactuca sativa L.) is the main leafy vegetable grown in Brazil. Its productivity and quality are limited by the growing season, the nearby environment and the type of cultivar adopted. The objective of this work was to verify at different times of the year the best planting environment for lettuce cultivation in a semi-humid tropical climate. For this purpose, an experiment was set up in three different seasons (October–November 2014, January–March, May–July 2015). The experimental design was randomized blocks, in a 3 × 3 × 2 factorial arrangement, consisting of three seasons, three cultivars (cvs. Vera®, Tainá® and Rafaela®) and two growing environments (low tunnel with beds protected with mulching consisting of soil protection with plastic fabric covering, and beds without protection or conventional cultivation) and four replicates per treatment. Plant biomass, stem length, head diameter, number of leaves per head and crop productivity were evaluated as response parameters. The results showed that the May–July period favored biomass production, head diameter and productivity. Despite the similarity between varieties, the variety Vera® is more productive in biomass, number of leaves per head, stem length and productivity. The low tunnel planting system with mulching is adequate under the conditions evaluated for lettuce cultivation. This system in the May–July period favors a superior development in the characteristics biomass, head diameter and productivity, if compared to conventional cultivation during the October–November period.
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