Postharvest handling of “etrog” citron (Citrus medica, L.) fruit

2016 ◽  
Vol 63 (1) ◽  
pp. 64-75 ◽  
Author(s):  
Joshua D. Klein ◽  
Yonit Raz Shalev ◽  
Shlomo Cohen ◽  
Elazar Fallik

Citron (Citrus medica, L.) fruits (“etrog” in Hebrew; plural “etrogim”) are used ritually in the Jewish holiday of Sukkot (Tabernacles), and can command as much as US$100/fruit, depending on quality. The etrog is unique among citrus fruits in that only the external attributes are of commercial importance. Maintaining physical fruit quality mandates the use of protective cushioning on the tree, at harvest, and in packaging. Growers use a wide range of chemical treatments post-harvest to reduce to a minimum the possibility of disfiguring insect or disease infestations. Most etrog varieties are highly susceptible to chilling injury if stored at less than 12°C. Etrogim lose water readily during storage, so fruit are stored and almost always marketed in plastic bags that limit water loss. Skin color is regulated with applications of ethylene or gibberellin, depending on whether specific markets prefer fruit that are greener or more yellow.

2015 ◽  
Vol 16 (1) ◽  
pp. 43-49 ◽  
Author(s):  
Chandrasekar S. Kousik ◽  
Scott Adkins ◽  
Craig G. Webster ◽  
William W. Turechek ◽  
Philip Stansly ◽  
...  

Watermelon vine decline (WVD) caused by the whitefly-transmitted Squash vein yellowing virus (SqVYV) has been a serious limiting factor in watermelon production in southwest and west-central Florida over the past few years. Symptoms of WVD typically appear as sudden decline of vines a few weeks before harvest or just after the first harvest. Fruit symptoms include rind necrosis and flesh discoloration that affects fruit quality and marketability. The combination of insecticide treatments consisting of an imidacloprid drench (Admire Pro, 560 ml/ha) at transplanting followed by two foliar applications of spiromesifen (Oberon, 2SC, 490 ml/ha) and reflective plastic mulch was evaluated for management of WVD during fall growing seasons of 2006, 2007, and 2009. Virus inoculum source was introduced by planting SqVYV-infected squash plants at the ends of each plot. In all three experiments, the insecticide-treated plots had significantly lower levels of WVD on foliage and fruit compared to non-treated plots. In 2007, the reflective plastic mulch was effective in reducing foliar WVD compared to non-reflective mulch, but not in 2006 and 2009. No significant interaction between plastic mulch and chemical treatments was observed on WVD development on foliage or fruit. Our results suggest that application of insecticides for managing whiteflies can help manage SqVYV-caused WVD. Accepted for publication 13 January 2015. Published 25 March 2015.


Author(s):  
João M. de S. Miranda ◽  
Ítalo H. L. Cavalcante ◽  
Inez V. de M. Oliveira ◽  
Paulo R. C. Lopes ◽  
Joston S. de Assis

ABSTRACTThe production of high quality fruits is a necessary factor for the adaptation and production of plant species with economic viability. Thus, an experiment was conducted from July 2012 to January 2013 to evaluate the fruit quality of the ‘Eva’ and ‘Princesa’ apple cultivars as a function of nitrogen fertilization in Petrolina, PE, Brazil. The experimental design consisted of randomized blocks, with treatments distributed in a factorial arrangement 2 x 4, corresponding to apple cultivars (Eva and Princesa) and nitrogen doses (40; 80; 120 and 160 kg of N ha-1), with four replications and three plants in each plot. The fruit characteristics, such as fruit mass, skin color (luminosity, chromaticity, and colour angle), size (width and length), pulp firmness, titratable acidity (TA), soluble solids (SS) and the SS/TA ratio, were recorded. Nitrogen doses do not affect fruit quality of studied apple cultivars. The fruit quality attributes are different between apple cultivars: fruit firmness, SS/TA ratio, fruit mass and fruit diameter are superior for Princesa cultivar, while the fruit length for Eva cultivar is superior.


2015 ◽  
Vol 37 (4) ◽  
pp. 1089-1104 ◽  
Author(s):  
GUSTAVO BRUNETTO ◽  
GEORGE WELLINGTON BASTOS DE MELO ◽  
MORENO TOSELLI ◽  
MAURIZIO QUARTIERI ◽  
MASSIMO TAGLIAVINI

ABSTRACT Fertilization of temperate fruit trees, such as grapevine ( Vitis spp.), apple ( Malus domestica), and pear ( Pyrus communis) is an important tool to achive maximum yield and fruit quality. Fertilizers are provided when soil fertility does not allow trees to express their genetic potential, and time and rate of application should be scheduled to promote fruit quality. Grapevine berries, must and wine quality are affected principally by N, that regulate the synthesis of some important compounds, such as anthocyanins, which are responsible for coloring of the must and the wine. Fermenation of the must may stop in grapes with low concentration of N because N is requested in high amount by yeasts. An N excess may increase the pulp to peel ratio, diluting the concentration of anthocyanins and promoting the migration of anthocyanins from berries to the growing plant organs; a decrease of grape juice soluble solid concentration is also expected because of an increase in vegetative growth. Potassium is also important for wine quality contributing to adequate berry maturation, concentration of sugars, synthesis of phenols and the regulation of pH and acidity. In apple and pear, Ca and K are important for fruit quality and storage. Potassium is the most important component of fruit, however, any excess should be avoided and an adequate K:Ca balance should be achieved. Adequate concentration of Ca in the fruit prevents pre- and post-harvest fruit disorders and, at the same time, increases tolerance to pathogens. Although N promotes adequate growth soil N availability should be monitored to avoid excessive N uptake that may decrease fruit skin color and storability.


Horticulturae ◽  
2018 ◽  
Vol 4 (3) ◽  
pp. 19 ◽  
Author(s):  
Daniel Chalupowicz ◽  
Sharon Alkalai-Tuvia ◽  
Merav Zaaroor-Presman ◽  
Elazar Fallik

Acorn squash fruits (Cucurbita pepo L.) are very sweet and are an excellent source of nutrients and vitamins. Very little information is available about their optimal storage temperature or how to extend their shelf life. The present goal was to elucidate the best storage temperature of this fruit, and to evaluate hot water rinsing and brushing (HWRB) technology to maintain fruit quality for several months. The optimal storage temperature was found to be 15 °C. However, treating the fruits with HWRB at 54 °C for 15 s and then storing them at 15 °C significantly maintained fruit quality for 3.5 months, as indicated by higher fruit firmness, lower decay incidence, and improved retention of green skin color.


2019 ◽  
Vol 48 (5) ◽  
pp. 95-101
Author(s):  
Ulzii-Orshikh Dorj ◽  
Uranbaigal Dejidbal ◽  
Hongseok Chae ◽  
Lkhagvadorj Batsambuu ◽  
Altanchimeg Badarch ◽  
...  

A new computer vision algorithm for citrus fruit quality classification based on the size of a single tree fruits was developed in this study. The image properties of area, perimeter, and diameter for the citrus fruits were measured by pixels. In order to estimate citrus fruit size in a realistic manner, the ratios of diameter, perimeter and area in pixel values in relation to the actual size of one fruit were determined. The total of 1860 citrus fruits were grouped based on diameter, perimeter, and area in pixels. The results of the grouping of citrus fruits by diameter, perimeter and area were compared with the results of the survey research into citrus fruit size as conducted by the Jeju Citrus Commission. Comparative results reveal that the image of the citrus fruit diameter in pixels demonstrate a more accurate size than the other two pixel values, i.e. perimeter and area.


2018 ◽  
Author(s):  
Solly Aryza

It is very challenging to recognize a face from an image due to the wide variety of face and the uncertain of face position. The research on detecting human faces in color image and in video sequence has been attracted with more and more people. In this paper, we propose a novel face detection method that achieves better detection rates. The new face detection algorithms based on skin color model in YCgCr chrominance space. Firstly, we build a skin Gaussian model in Cg-Cr color space. Secondly, a calculation of correlation coefficient is performed between the given template and the candidates. Experimental results demonstrate that our system has achieved high detection rates and low false positives over a wide range of facial variations in color, position and varying lighting conditions.


2020 ◽  
Vol 77 (4) ◽  
pp. 627-632
Author(s):  
Swarajya Laxmi Nayak ◽  
Shruti Sethi ◽  
R.R. Sharma ◽  
A.K. Dubey ◽  
Arpan Bhowmik

2015 ◽  
pp. 141-146 ◽  
Author(s):  
Z. Megías ◽  
A. Barrera ◽  
S. Manzano ◽  
C. Martínez ◽  
D. Garrido ◽  
...  

2020 ◽  
pp. SP511-2020-34
Author(s):  
L. O. Andrews ◽  
R. J. Payne ◽  
G. T. Swindles

AbstractTestate amoebae are a frequently used palaeoecological proxy for reconstructing changes in palaeohydrological conditions, particularly in studies of Sphagnum-dominated peatlands. Their use in palaeoecological studies has increased following the development of transfer functions, allowing for the quantitative reconstruction of water-table depth changes through time. Increasingly, they are included in non-pollen palynomorph (NPP) studies alongside a wide range of other proxies, representing a valuable tool, particularly in multi-proxy studies.Testate amoebae have been used for qualitative assessment of palaeohydrology in NPP studies and may aid the verification of environmental interpretations of conditions inferred from curves of NPP with unknown ecology and taxonomy. Their usefulness in such studies is limited by the destruction of tests owing to harsh chemical treatments used in pollen preparation methods. This makes community distribution data of testate amoebae derived by these methods largely unsuitable for quantitative assessment of water-table depth. Furthermore, many palynological studies combine testate amoebae as one single curve, losing further ecological detail. Patterns of change of surviving species, most commonly of Assulina, Archerella, Arcella, Hyalosphenia and Archerella flavum, remain relatively unaffected and therefore can still be useful for interpreting qualitative changes in hydrological conditions through time, particularly when coupled with other proxies.


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