The objective of the present research was to identify the causal agent of soft rot disease in the stems of pitahaya plants (Hylocereus undatus (Haw.) Britton & Rose), also known as dragon fruit, in two production areas of Peru. Typical symptoms observed include rotting and soft consistency in stems, as well as yellowish colourations, which usually begin at the tips and outer edges of the stems and extend until they are completely decomposed. Symptomatic samples of pitahaya stalks were collected from two commercial fields, the first from the district of Independencia, Pisco, Ica, and the second from the district of Naranjos, Rioja, San Martin. The collected samples were transferred to the phytopathology laboratory of the National Agrarian University – La Molina where 19 bacterial colonies isolated from symptomatic stem tissue were processed. Nine bacterial colonies were selected fro...

The contamination of soils by heavy metals is a current problem for agricultural production. Rapid access and reliability to heavy metal concentration such as cadmium is crucial for international trade. In the present study, visible and near infrared (VIS-NIR) spectroscopy, combined with linear and statistical methods, were used to predict the cadmium concentration of organic cocoa bean samples. Partial Least Square Regression (PLSR) and Support Vector Regression (SVR) were implemented to estimate the content of this heavy metal from hyperspectral imaging and chemical analysis. Competitive Adaptive Reweighted Sampling Method (CARS) and Jackknife method were used for selecting optimal wavelength. The SVR model performed satisfactorily with the use of 45 resulting wavelengths from optimization using CARS and the Jackknife method, with an adjusted coefficient for the test R2 of 0.9401 and a...

This article summarizes our investigation about technologies for moisture sensing, a parameter of analysis and study over many years because it serves to estimate the quality, and performance at commercial and environmental level. This paper presents some contributions. First, we developed a new classification about the most representative system in research and scientific articles. We shows applications of the technology in recent years according to the consulted articles. Also, we expose systems for soil and vegetation moisture measurement, this is an important application in this decade because helps to agriculture and many control applications (forestall fires, earthquakes, etc.). Finally, the tendency about new investigations is presented. This paper is important for microwave sensors designers and investigators in moisture control, because they will have a reference about what kind...

Intelligent packaging represents a sustainable solution for food preservation by enabling the monitoring of freshness through chromatic changes. In this study, a biofilm based on polyvinyl alcohol (PVA), nanocellulose (NC) extracted from rice straw and blueberry extract was developed and evaluated for its performance as a visual freshness indicator in tilapia fillets. Nanocellulose, obtained by TEMPO oxidation, exhibited proper integration into the polymeric matrix according to transmission electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis and X-ray diffraction analysis. The biofilms improved their mechanical properties with the addition of NC, by increasing tensile strength and reducing water solubility. However, the incorporation of anthocyanins increased solubility and water vapor permeability due to their hydrophilic character. Despite this, the...

Background: Solanum tuberosum L. is an Andean tuber that is mainly characterized by its antioxidant properties. Objective: To evaluate the healing activity of an S. tuberosum-based ointment on wounds induced in mice. Material and methods: Ethanolic extracts of peel and pulp of tubers of S. tuberosum "Tumbay yellow potato"were prepared, which were incorporated into 1% and 2% ointment formulations. Mus musculus Balb/c with induced wound were distributed in the following working groups: Group I (Negative Control), Group II (Positive Control: Neomycin, Polymyxin B and Bacitracin Ointment) and Groups III and IV (Ointment at 1 % and 2% of S. tuberosum extract, respectively), daily administration of topical treatments were carried out for 07 days. Wound closure was determined during the experimentation time, then euthanized with sodium pentobarbital 60 mg/kg b.w. (i.p.) to obtain skin samples f...