scholarly journals Percentage of Dry Matter and Oil Content Are Not Reliable Indicators of Fruit Maturity or Quality in Late-harvested `Hass' Avocado

HortScience ◽  
2000 ◽  
Vol 35 (4) ◽  
pp. 694-695 ◽  
Author(s):  
Peter J. Hofman ◽  
Marcelle Jobin-Décor ◽  
Janet Giles

The potential to use percentage of dry matter (DM) and/or oil of the flesh of `Hass' avocado as a maturity standard to determine the latest harvest for acceptable fruit quality, was investigated. `Hass' avocado fruit were harvested from early October to mid-January from a commercial orchard in subtropical Queensland. The percentage of DM and oil changed little during the harvest period, and the eating quality of the flesh remained high. However, the incidence of body rots (caused mainly by Colletotrichum sp.) and the flesh disorders grey pulp and vascular browning, increased with harvest. These results indicate that percentage of DM and oil are not reliable late-maturity standards because of the inconsistent change with later harvests, and that disease and internal disorders can be the main determinants of latest acceptable harvest, rather than eating quality.

1969 ◽  
Vol 95 (1-2) ◽  
pp. 15-23
Author(s):  
Jorge A. Osuna-García ◽  
Gilles Doyon ◽  
Samuel Salazar-García ◽  
Ricardo Goenaga ◽  
Isidro J. L. González-Durán

Mexico is the main 'Hass' avocado exporter in the world. More than 300,0001 are exported every year. The United States of America, Japan, the European Union, and Canada are the main importer countries. Recently, 'Hass'avocado shipments to Canada containing fruit with skin blackening have been rejected since this characteristic is associated with low pulp firmness and short shelf life. The objective of this study was to determine the relationship between skin color of 'Hass' avocado fruit with quality characteristics. Fruit varying in black skin color (from 0 to 100%, categories 1 to 5) were collected from two different packinghouses in Michoacán, Mexico. Treatments were arranged in a split-plot design with five replications. Significant differences were detected between packinghouses for weight, length, skin color ('a', ‘b’, chroma and hue) and pulp firmness but not for width, dry matter content or the Avocado Maturity Index (AMI). As color skin category increased towards more blackened fruit, AMI value increased, firmness decreased but dry matter content did not change. These results provide evidence that fruit skin blackening is not associated with lower fruit quality, but it did lower pulp firmness at fruit packing.


2018 ◽  
Vol 174 ◽  
pp. 41-49 ◽  
Author(s):  
Khayelihle Ncama ◽  
Lembe S. Magwaza ◽  
Carlos A. Poblete-Echeverría ◽  
Hélène H. Nieuwoudt ◽  
Samson Z. Tesfay ◽  
...  

2014 ◽  
Vol 32 (3) ◽  
pp. 399-406 ◽  
Author(s):  
Catarina Pedro Carvalho ◽  
María Alejandra Velásquez ◽  
Zelda Van Rooyen

Colombia has become an important producer of 'Hass' avocado in the last three years; however, a minimum dry matter content has not been established as a maturity index for harvest. The aim of this study was to determine the correlation between oil percentage and dry matter content in order to establish a minimum harvest index for 'Hass' avocado fruits grown in Colombia. Samples were collected for maturity determinations over three years of 'Hass' avocado fruit cultivation from fifteen different orchards in the department of Antioquia in order to determine the dry matter and oil percentage of fruits throughout the season. A simple linear relationship between oil content and dry matter was thus established. The equations for all of the studied orchards presented a good correlation coefficient, ranging between 0.70 on the Cartucho orchard in the municipality of Retiro and 0.99 on the Gacamayas and Paraiso orchards in the municipality of Entrerrios and Retiro. Using the minimal oil standard of 11.2% as a reference, the orchards that were found to have a high dry matter percentage at harvest were Cartucho in Retiro (26%), followed by Piedras Blancas and Santa Cruz in the municipality of Venecia (25%); while the 'Hass' avocado fruit from the Cebadero orchard in Retiro, Coconi in the municipality of La Ceja and Guacamayas in Entrerrios reached this oil standard at 22% dry matter, which could be a commercial advantage. Based on these oil content results, a minimal dry matter index of 23.5% was proposed as a harvest maturity indicator for 'Hass' avocado grown in Colombia. This harvesting index will need to be refined over time and with the addition of samples from more regions and climatic data profiles.


Plants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 358
Author(s):  
Muhammad Moaaz Ali ◽  
Raheel Anwar ◽  
Ahmed F. Yousef ◽  
Binqi Li ◽  
Andrea Luvisi ◽  
...  

Fruit quality is certainly influenced by biotic and abiotic factors, and a main quality attribute is the external appearance of the fruit. Various possible agronomical approaches are able to regulate the fruit microenvironment and, consequently, improve fruit quality and market value. Among these, fruit bagging has recently become an integral part of fruits’ domestic and export markets in countries such as Japan, China, Korea Australia and the USA because it is a safe and eco-friendly technique to protect fruits from multiple stresses, preserving or improving the overall quality. Despite increasing global importance, the development of suitable bagging materials and, above all, their use in the field is quite laborious, so that serious efforts are required to enhance and standardize bagging material according to the need of the crops/fruits. This review provides information about the effects of bagging technique on the fruit aspect and texture, which are the main determinants of consumer choice.


2006 ◽  
Vol 46 (9) ◽  
pp. 1195 ◽  
Author(s):  
J. R. Marques ◽  
P. J. Hofman ◽  
A. H. Wearing

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.


Author(s):  
J. Racskó ◽  
J. Nagy ◽  
Z. Soltész ◽  
M. Soltész ◽  
P. T. Nagy ◽  
...  

The aim of the present study was to determine the effect of nitrogen supply on yield and fruit quality of apple cultivars and to explore the relationships between canopy density and the different fruit quality parameters. The experiments were carried out at Kálmánháza, in Eastern Hungary in a private orchard in 2003-2004. The response of four apple cultivars ('Elstar', 'Gala Prince', 'Granny Smith', 'Idared') to different nitrogen dosages was studied. The assessed and calculated indices were: yield, fruit diameter, fruit height, shape index, fruit mass, firmness, dry matter content and colouration. The results indicated that nitrogen fertilization has a significant effect on the yield and fruit quality of apple cultivars. The calculated specific yield values were reduced by the application of nitrogen via the increase in the volume of the canopy. An opposit trend was observed for fruit diameter, fruit height and fruit weight, which increased with increasing nitrogen supply. The reduced shape index caused flattening of fruits. However, the improvement of fruit quality via increasing nitrogen dosage is only virtual, since these dosages increase the fruit size, but firmness, dry matter content and colouration are diminished, which decreases the value of the fruits on the market. The authors also studied the relationships between canopy density responsible for assimilation and light supply of the fruits and the different fruit quality parameters. The closest linear inversely proportional relationship was found in the case of colouration. There was a negative linear relationship between canopy density and firmness or dry matter content. The relationship between canopy density and fruit mass could be described by a quadratic polinomial function.


2020 ◽  
Vol 175 ◽  
pp. 01012
Author(s):  
Natalia Kovtunova ◽  
Vladimir Kovtunov ◽  
Aleksey Popov ◽  
Aleksandr Volodin ◽  
Elena Shishova ◽  
...  

Sweet sorghum hybrids F1 in productivity can surpass the parental forms on 50-60%. Thus the breeding process is aimed to develop first generation hybrids with a strong potential of productivity and quality of green mass and silage. The purpose of the work is to study heritability and heterosis of the quantitative traits of sweet sorghum hybrids F1 obtained on a sterile basis. The study was conducted in 2013-2015 on the lines with cytoplasmic male sterility (‘A-63’, ‘Knyazhna’, ‘APV-1115), the varieties (‘Listvenit’, ‘Severnoe 44’, ‘Zernogradskoe 454’, ‘Stavropolskoe 36’, ‘Galiya’ and ‘Larets’) and the hybrids. The inheritance of green mass productivity and absolutely dry matter, the length of a vegetation period, plant height and leaf formation (foliage), protein content in dry matter of the hybrids occurred according to the type of dominance and overdominance. It has been determined that while choosing the parental forms for hybridization it’s essential to select the forms with differences in the vegetation period of 4-6 days to avoid the dominance of late maturity. The height pollinator increase results in the hybrid height increase and large heterosis. It’s necessary to select the parental forms with maximum foliage to improve leaf formation in the hybrids.


Foods ◽  
2019 ◽  
Vol 8 (7) ◽  
pp. 264 ◽  
Author(s):  
Lara Moran ◽  
Shannon S. Wilson ◽  
Cormac K. McElhinney ◽  
Frank J. Monahan ◽  
Mark McGee ◽  
...  

The objective was to compare the quality of beef from bulls reared in typical Irish indoor systems or in novel grass-based systems. Bulls were assigned to one of the following systems: (a) grass silage plus barley-based concentrate ad libitum (CON); (b) grass silage ad libitum plus 5 kg of concentrate (SC); (c) grazed grass without supplementation (G0); (d) grazed grass plus 0.5 kg of the dietary dry matter intake as concentrate (GC) for (100 days) until slaughter (14.99 months). Carcass characteristics and pH decline were recorded. Longissimus thoracis was collected for analytical and sensory analysis. Lower carcass weight, conformation and fatness scores were found for grazing compared to CON and SC groups. CON bulls had highest intramuscular fat and lighter meat colour compared with grazing bulls. The SC meat (14 days aged) was rated higher for tenderness, texture, flavour and acceptability compared with grazing groups. CON saturated and monounsaturated fatty acid (FA) concentration was highest, conversely, omega-3 FA concentration was higher for GC compared with CON, while no differences were found in polyunsaturated FA. In conclusion, while market fatness specification was not reached by grazed grass treatments, beef eating quality was not detrimentally affected and nutritional quality was improved.


1993 ◽  
Vol 33 (3) ◽  
pp. 353 ◽  
Author(s):  
AP George ◽  
RJ Nissen ◽  
T Rassmussen

Combinations of 3 methods of controlling tree size (use of the growth retardant paclobutrazol, postharvest topping, and autumn cincturing) were evaluated for their effects on growth, yield, and fruit quality of the low chill nectarine cv. Sundowner in subtropical Australia. Compared with controls over 3 seasons, paclobutrazol used alone reduced tree size by 34-52%, with further reductions when combined with light and severe postharvest topping (by 5-25 and 58-71%, respectively). Yield efficiency (as measured by yield per unit canopy volume) was significantly improved by paclobutrazol and was doubled when paclobutrazol was combined with severe postharvest topping. Although this combination reduced time associated with pruning, thinning, and harvesting, it had the disadvantage of delaying flowering and, consequently, fruit maturity in the subsequent harvest season. Light postharvest topping and autumn cincturing used with paclobutrazol had little effect on yield efficiency, fruit quality, or harvest period. The seasonal pattern of starch reserves for twigs was similar for all treatments, with starch levels falling to a minimum during the early harvest period. Measurements of starch in the major tree organs showed that at very low harvest increments (<10) there was little or no depletion of starch from the twigs and leaves, but as harvest increments increased (range 10-40), there was increasing starch depletion, in order of priority, from the roots, trunks, and limbs.


Sign in / Sign up

Export Citation Format

Share Document