Maturation and Resting of Sweet Pepper Fruits on Physiological Quality and Biochemical Response of Seeds

Abstract The post-harvest resting of the fruits can improve seed physiological quality ,once it allows the seed to complete the maturation process, so it has been a common practice in vegetable seed companies, however, there are a few studies of this technique in sweet pepper. The objective of this research was to evaluate physiological quality, and biochemical response of sweet's peppers in regarding on the stage of maturation and the post-harvest rest of the fruits. The experimental was conducted in a 4x2 factorial, being the first factor comprised four maturation stages (35, 50, 65 and 80 days after anthesis) and, the second the post-harvest management of fruits, with and without a temporary storage of seven days. Seeds were evaluated for water content, weight of thousand seeds, germination, vigor, superoxide dismutase, catalase and peroxidase activities, lipid peroxidation and hydrogen peroxide content. Fruit harvest time indicated is 80 days after anthesis (fruits 100% yellow) when seeds showed maximum germination and vigor. The post-harvest resting of the fruits was beneficial to seed physiological quality, weight of one thousand seeds and to reduce hydrogen peroxide content. Seeds of higher physiological quality showed lower superoxide dismutase and catalase enzyme activity, so they can be used as a marker of physiological quality in sweet pepper seeds.

Reação de genótipos de batata-doce a nematóides de galhas em condições de temperatura elevada / Reaction of genotypes of the sweet potato to nematode galls in high temperature conditions

O objetivo do trabalho foi avaliar a reação de genótipos de batata-doce oriundos de sementes botânicas quanto a nematóides de galhas (M. incognita raça 2 e M. javanica) em condições de temperatura elevada. Para cada espécie de nematóides, foi instalado um experimento utilizando o delineamento experimental inteiramente casualizado com três repetições. Foram avaliados 25 genótipos dos quais 20 são famílias de meios-irmãos (oriundo de um campo de policruzamento); cinco cultivares (Amanda, Ana Clara, Bárbara, Duda e Marcela) e a cultivar de tomate Santa Clara, suscetível aos nematóides. A classificação da resistência foi feita pelo Índice de Reprodução (IR%), no período mais quente do ano (janeiro/fevereiro), sobre condições temperatura média do solo de 26 ºC na região Sul do Estado do Tocantins. Avaliou-se também o número médio de galhas por sistema radicular, tamanho médio das galhas e posicionamento das galhas. Em condição de temperatura elevada, a espécie M. javanica foi mais agressiva do que M. incognita raça 2, originando galhas em maior número e de maior tamanho, principalmente nas raízes secundárias. Os genótipos BDFMI-16, BDFMI-78, Bárbara e Marcela são resistentes a M. incognita raça 2. Para o isolado M. javanica, o genótipo BDFMI-04 e BDFMI-16 e as cultivares Amanda e Duda são classificados como muito resistentes. O genótipo BDFMI-16 resistente a M. incognita raça 2 e M. javanica é promissor para uso no Estado do Tocantins ou então compor programas de melhoramento cujo objetivo é desenvolver genótipos resistentes às duas espécies de nematóides.

The objective of this study was to evaluate the response of sweet potato genotypes derived from botanical seed gall nematode (M. incognita race 2 and M. javanica) in high temperature conditions. For each species of nematodes, an experiment was conducted using completely randomized design with three replications. Were evaluated 25 genotypes of which 20 are half-sib families (coming from a field polycross); five cultivars (Amanda, Ana Clara, Barbara Duda and Marcela) and tomato cultivar Santa Clara, susceptible to nematodes. The classification was made by the resistance Rendering Index (IR%), the hottest period of the year (January/February) on average soil temperature conditions of 26 ° C in the southern region of the State of Tocantins. Also evaluated the mean number of galls per root system galled average size and positioning of the gall. Under high temperature condition, the species M. javanica was more aggressive than M. incognita race 2, causing galls in greater numbers and larger, especially in the secondary roots. Genotypes BDFMI-16, BDFMI-78, and cultivars Barbara and Marcela are resistant M. incognita race 2. To isolate M. javanica, the genotype BDFMI-04 and BDFMI-16 and cultivars Amanda and Duda are classified as very resistant. Genotype BDFMI 16 resistant M. incognita race 2 and M. javanica is promising for use in the State of Tocantins and then compose breeding programs aimed at developing genotypes resistant to both nematode species.