HYDROTHERMIC TREATMENT IN THE SOFT ROT CONTROL IN POTATOES AND THEIR CHANGES IN THE POST-HARVEST CHARACTERISTICS

Several strategies have been the object of studies to control soft rot in potatoes, but in many cases they are based on methods that, even though they present promising results, demand a high investment, besides the difficulty of being applied in large volumes, which makes the use of hydrothermal treatment an interesting alternative. The aim of this study was to evaluate the influence of different immersion temperatures used in the hydrothermal treatment on the post-harvest quality of the treated tubers. The experiment was conducted following a completely randomized design with five immersion temperatures: control, 40, 50, 60 and 70 C °, and five storage periods: 0, 5, 10, 15 and 20 days. Post-harvest quality determination was performed by evaluating pulp firmness, pH, titratable acidity (% citric acid) and soluble solids content (° Brix) Throughout the storage period the tubers with symptoms of soft rot were counted and discarded. The immersion temperature caused changes in the parameters of pulp firmness, titratable acidity and soluble solids content. Tubers submitted to immersion temperature of 70 ° C were all eliminated on the 5th day of evaluation. The immersion of potatoes at 40 ° C was the most efficient in reducing the appearance of soft rot, while maintaining the physical-chemical characteristics of the treated tubers during the storage period of 20 days.Several strategies have been the object of studies to control soft rot in potatoes, but in many cases they are based on methods that, even though they present promising results, demand a high investment, besides the difficulty of being applied in large volumes, which makes the use of hydrothermal treatment an interesting alternative. The aim of this study was to evaluate the influence of different immersion temperatures used in the hydrothermal treatment on the post-harvest quality of the treated tubers. The experiment was conducted following a completely randomized design with five immersion temperatures: control, 40, 50, 60 and 70 C °, and five storage periods: 0, 5, 10, 15 and 20 days. Post-harvest quality determination was performed by evaluating pulp firmness, pH, titratable acidity (% citric acid) and soluble solids content (° Brix) Throughout the storage period the tubers with symptoms of soft rot were counted and discarded. The immersion temperature caused changes in the parameters of pulp firmness, titratable acidity and soluble solids content. Tubers submitted to immersion temperature of 70 ° C were all eliminated on the 5th day of evaluation. The immersion of potatoes at 40 ° C was the most efficient in reducing the appearance of soft rot, while maintaining the physical-chemical characteristics of the treated tubers during the storage period of 20 days

SIMULAÇÃO DE DESFOLHAS EM DIFERENTES ESTÁDIOS VEGETATIVO NA CULTURA DA SOJA

A cultura da soja, durante todo seu ciclo, está susceptível ao ataque de insetos-pragas que podem reduzir sua produtividade final. Objetivou-se com este trabalho avaliar o efeito de desfolhas artificiais em diferentes estádios vegetativos na cultura da soja. O experimento foi implantado na área experimental do Instituto Federal Goiano – Campus Morrinhos e conduzido em delineamento com blocos ao acaso, com oito tratamentos e quatro repetições. A cultivar BRS Valiosa RR foi submetida aos seguintes tratamentos: T0: sem desfolha; T1: remoção de um folíolo por trifólio em V2 até V8; T2 remoção de um folíolo por trifólio em V3 até V8; e assim sucessivamente até chegar ao último tratamento T7: remoção de um folíolo por trifólio em V8. As variáveis analisadas foram: altura de plantas, inserção de 1º vagem, índice de clorofila, número de ramos, número de vagens, número de grãos por vagem, peso de mil grãos e produtividade final da cultura. Os dados foram submetidos à análise de variância pelo teste de Scott-Knott a 5% de probabilidade, por meio do software ASSISTAT. Conclui-se que desfolhas contínuas em nível de 33% nos estádios iniciais da cultura reduz o porte da planta, o número de vagens por planta e a produtividade final na cultura da soja

SIMULAÇÃO DE DESFOLHAS EM DIFERENTES ESTÁDIOS VEGETATIVO NA CULTURA DA SOJA

A cultura da soja, durante todo seu ciclo, está susceptível ao ataque de insetos-pragas que podem reduzir sua produtividade final. Objetivou-se com este trabalho avaliar o efeito de desfolhas artificiais em diferentes estádios vegetativos na cultura da soja. O experimento foi implantado na área experimental do Instituto Federal Goiano – Campus Morrinhos e conduzido em delineamento com blocos ao acaso, com oito tratamentos e quatro repetições. A cultivar BRS Valiosa RR foi submetida aos seguintes tratamentos: T0: sem desfolha; T1: remoção de um folíolo por trifólio em V2 até V8; T2 remoção de um folíolo por trifólio em V3 até V8; e assim sucessivamente até chegar ao último tratamento T7: remoção de um folíolo por trifólio em V8. As variáveis analisadas foram: altura de plantas, inserção de 1º vagem, índice de clorofila, número de ramos, número de vagens, número de grãos por vagem, peso de mil grãos e produtividade final da cultura. Os dados foram submetidos à análise de variância pelo teste de Scott-Knott a 5% de probabilidade, por meio do software ASSISTAT. Conclui-se que desfolhas contínuas em nível de 33% nos estádios iniciais da cultura reduz o porte da planta, o número de vagens por planta e a produtividade final na cultura da soja

VISUAL QUALITY AND PHYSICAL-CHEMICAL CHARACTERISTICS IN POTATO TUBERS TREATED WITH HYDROGEN PEROXIDE

Unconventional techniques such as the use of visible ultraviolet light (UV-C) and physical treatments have been used to combat post-harvest diseases. Attention has been focused on the use of hydrogen peroxide, but little is known about its effects on the control of bacteria causing soft rot. The objective of this study was to evaluate the incidence of soft rot and physical-chemical and visual characteristics in potato tubers (Solanum tuberosum L.) treated with hydrogen peroxide. The experiment was conducted following a completely randomized design in subdivide plots scheme with four treatments: 0, 50, 100 and 150ppm of hydrogen peroxide whit an inoculated plot and a non inoculated. The visual aspects were evaluated by for to the incidence of soft rot appearance of shoots. pH, titratable acidity (% citric acid), soluble solids content, pulp firmness and total sugar content were used to determine post-harvest quality. Hydrogen peroxide was not effective in controlling soft rot in potato tubers, but increased the metabolic activity of tubers leading to an increase in soluble solids content and reduced in titratable acidity