Between-tree variation in fruit quality and fruit mineral concentrations of Hass avocados

Abstract

Inconsistent internal fruit quality in Hass avocados affects consumer confidence. To determine the influence of individual trees on fruit quality, Hass avocado fruit were harvested from adjacent trees of similar external appearance in 3 commercial orchards in 1998 and 1 orchard in 1999. The trees in each orchard were grown with similar commercial practices and in similar soil types. Within each location, there were significant (P<0.05) differences in the mean ripe fruit quality between trees with respect to fruit body rot severity (mainly anthracnose) with and without cold storage, internal disorders severity due to diffuse discolouration and vascular browning (after cold storage), days to ripen, percentage dry matter, and the percentage of the skin area with purple-black colour when ripe. These effects were also noted in the same orchard in 1999. There were significant (P<0.05) differences in fruit flesh calcium, magnesium, potassium, boron and zinc concentrations between trees. Significant (P<0.05) correlations were observed between average fruit mineral concentrations in each tree (particularly calcium, magnesium and potassium) and body rot severity, percentage dry matter and fruit mass. There was little conclusive evidence that characteristics such as the growth of the non-suberised roots or the degree of scion under- or overgrowth was involved in these tree effects; however, differences between trees with respect to other rootstock characteristics may be involved. The inconsistency of the correlations across sites and years suggested that other factors apart from tree influences could also affect the relationship between fruit minerals and fruit quality.

Near infrared spectroscopy as a rapid non-invasive tool for agricultural and industrial process management with special reference to avocado and sandalwood industries

“…Geographic location (growing district) effects may have a major consequence on model robustness as fruit composition is subject to within tree variability (i.e., tree age, crop load, position within the tree, light effects); within orchard variability (i.e., location of tree, light effects); and intra-orchard variability, such as soil characteristics, nutrition, weather conditions, fruit age and seasonal variability [31,32]. The influence of geographic location variability on %DM for whole avocado fruit was subsequently investigated over the 2008 growing season.…”

Relationships between Nut Size, Kernel Quality, Nutritional Composition and Levels of Outcrossing in Three Macadamia Cultivars

“…These results might relate to the phloem mobility of potassium. Fruit calcium concentrations are often strongly negatively related to fruit mass whereas potassium concentrations are often more-weakly negatively related, or not related significantly, to fruit mass [93][94][95][96][97]. However, positive relationships between fruit potassium concentration and fruit mass have sometimes been detected in apple and avocado [94,95].…”

Nutrición orgánica del aguacate cv. “Hass” y efecto nutrimental y agronómico

“…This is important as organic avocados in Michoacán, hardly able to overcome 7 cm long with weights less than 180 g while the fruit reaches 9 cm long easily exceeds 180 g of weight, giving better quality (Shmuel 1987). Meanwhile, Marques et al (2009) mentioned that nutrition has an immediate effect on the quality of the fruit, while Lovatt (1999) notes that there is an increase in the final a la disponibilidad nutricional, como fue demostrado por Zicah et al (1987), que tanto la brotación vegetativa como el amarre de fruto tienen relación con el nitrógeno disponible, entre otros compuestos.…”

“…Esto es importante pues en Michoacán los aguacates orgánicos, difícilmente logran superar 7 cm de longitud con pesos inferiores a 180 g. mientras que el fruto que alcanza 9 cm de longitud rebasa fácilmente 180 g de peso, confiriéndole mayor calidad (Shmuel, 1987). Por su parte, Marques et al (2009), mencionan que la nutrición tiene un efecto inmediato en la calidad del fruto, mientras que Lovatt (1999), señala que hay un incremento en el tamaño final del fruto, quedando pequeño el fruto en condiciones de nutrición deficiente, esto es lo que puede estar pasando en las huertas orgánicas que no alcanzan un buen tamaño de fruto (<8 cm de longitud).…”