scholarly journals Mechanical Thinning of Mandarins with a Branch Shaker

2020 ◽  
Vol 30 (6) ◽  
pp. 745-750
Author(s):  
Coral Ortiz ◽  
Antonio Torregrosa ◽  
Enrique Ortí ◽  
Sebastià Balasch
Keyword(s):  
Research Study ◽  
Fruit Size ◽  
Citrus Fruit ◽  
Fruit Yield ◽  
Citrus Reticulata ◽  
Labor Costs ◽  
Thinning Operation ◽  
Thinning Operations ◽  
Mechanical Thinning ◽  
Increase Efficiency

Thinning is the process of removing some flowers or fruit to increase fruit size at harvest. In the Valencia region of Spain, the thinning operation for citrus fruit (Citreae) is performed for some mandarin varieties. This is always performed manually; however, this method is very expensive. The goal of this research study was to assess the mechanical thinning of mandarin (Citrus reticulata) using a hand-held branch shaker. Different thinning treatments were conducted over a 3-year period. The gasoline-powered branch shaker was capable of detaching fruit four- to five-times faster than manual thinning. Final fruit size was significantly higher using manual and mechanical thinning compared with a no thinning treatment. Similar final fruit size was obtained with manual and mechanical thinning. However, no significant differences were found in final fruit yield by weight among no thinning, mechanical thinning, and manual thinning treatments. The use of a branch shaker could be recommended for thinning operations to increase efficiency, reduce labor costs, and obtain larger and higher-quality fruit.

scholarly journals The Potential Use of Metamitron as a Chemical Fruit-thinning Agent in Mandarin

2018 ◽  
Vol 28 (1) ◽  
pp. 28-34 ◽  
Author(s):  
Ockert P.J. Stander ◽  
Johané Botes ◽  
Cornelius Krogscheepers
Keyword(s):  
Fruit Set ◽  
Fruit Size ◽  
Fruit Trees ◽  
Fruit Yield ◽  
Citrus Reticulata ◽  
Alternate Bearing ◽  
Fruit Thinning ◽  
Total Carbohydrates ◽  
Leaf Carbohydrates ◽  
Potential Use

Under conditions of profuse flowering and excessive fruit set, citrus (Citrus sp.) fruit need to be thinned to increase the size of remaining fruit, reduce the intensity of alternate bearing, or both. Metamitron was recently developed as a chemical fruit-thinning agent for apple (Malus ×domestica) and pear (Pyrus communis), and it inhibits photosynthesis and is thought to transiently reduce the carbohydrate pool in fruit trees. Citrus trees are sensitive to carbohydrate stress during and immediately after flowering, but the response of citrus to foliar treatment with a photosynthesis inhibitor, such as metamitron, is unknown. The purpose of this study was to evaluate metamitron for its effects on leaf carbohydrates and its ability to chemically thin citrus fruitlets. Significant fruit-thinning effects were found in all the experiments conducted over two seasons. A 300 mg·L−1 metamitron treatment reduced leaf sugars and leaf total carbohydrates, and consistently reduced the total number of fruit per tree in both seasons in ‘Nadorcott’ mandarin (Citrus reticulata), irrespective of the timing of application. In the second season, a reduction in fruit yield was reported with an increase in metamitron concentration, both in mass and number of fruit per tree. A 150 mg·L−1 metamitron treatment in November had no fruit-thinning effects, and fruit yield was not different from the control. The application of metamitron did not increase the fruit size of ‘Nadorcott’ mandarin and had no direct effect on other fruit quality attributes in either season. Metamitron can be used as a chemical fruit-thinning agent to reduce fruit numbers in ‘Nadorcott’ mandarin, but an increase in fruit size or quality should not be expected.

Protected Culture Systems for Strawberry Production

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 459d-459
Author(s):  
Fumiomi Takeda ◽  
Paul R. Adler ◽  
D. Michael Glenn
Keyword(s):  
Light Intensity ◽  
Fruit Size ◽  
Fruit Production ◽  
Hydroponic Culture ◽  
Production Cycle ◽  
Soilless Culture ◽  
Labor Costs ◽  
Culture Systems ◽  
Nutrient Film Technique ◽  
Plant Densities

Strawberry plants (cvs. Camarosa, Chandler, Sweet Charlie, Primetime, Jewel, and Tribute) were grown in soilless culture systems in a greenhouse from October to May. Fresh-dug and runner-tip Aplug® plants were transplanted into two systems: vertically stacked pots (24 plants/m2) containing perlite and horizontal nutrient film technique troughs (13 plants/m2). Plants were fertigated continuously with recirculating nutrient solution. In a 7-month production cycle, the plug plants bloomed earlier and produced more fruit during the first month of harvest (December) than the fresh-dug plants. Higher yields from plug plants were a result of more fruit numbers and not larger fruit size. Fruit production averaged 6.0 and 3.5 kg/m2 in the trough and pot systems, respectively. The vertical growing system allows greater plant densities, but light intensity reaching the plants in the lower sections of the tower can be less than 20% of levels measured at the top. Establishment costs of protected culture systems are higher, but production is earlier and labor costs are typically reduced. Greenhouse hydroponic culture systems could extend the winter strawberry production to more northern locations.

scholarly journals Identification of Lasiodiplodia pseudotheobromae Causing Fruit Rot of Citrus in China

Plants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 202
Author(s):  
Jianghua Chen ◽  
Zihang Zhu ◽  
Yanping Fu ◽  
Jiasen Cheng ◽  
Jiatao Xie ◽  
...  
Keyword(s):  
Phylogenetic Analyses ◽  
Elongation Factor ◽  
Morphological Characteristics ◽  
Citrus Fruit ◽  
Economic Loss ◽  
Fruit Rot ◽  
Post Inoculation ◽  
Citrus Reticulata ◽  
Postharvest Diseases ◽  
Citrus Reticulata Blanco

Considering the huge economic loss caused by postharvest diseases, the identification and prevention of citrus postharvest diseases is vital to the citrus industry. In 2018, 16 decayed citrus fruit from four citrus varieties—Satsuma mandarin (Citrus unshiu), Ponkan (Citrus reticulata Blanco cv. Ponkan), Nanfeng mandarin (Citrus reticulata cv. nanfengmiju), and Sugar orange (Citrus reticulata Blanco)—showing soft rot and sogginess on their surfaces and covered with white mycelia were collected from storage rooms in seven provinces. The pathogens were isolated and the pathogenicity of the isolates was tested. The fungal strains were identified as Lasiodiplodia pseudotheobromae based on their morphological characteristics and phylogenetic analyses using the internal transcribed spacer regions (ITS), translation elongation factor 1-α gene (TEF), and beta-tubulin (TUB) gene sequences. The strains could infect wounded citrus fruit and cause decay within two days post inoculation, but could not infect unwounded fruit. To our knowledge, this is the first report of citrus fruit decay caused by L. pseudotheobromae in China.

scholarly journals Morphology Characterization, Molecular Phylogeny, and Pathogenicity of Diaporthe passifloricola on Citrus reticulata cv. Nanfengmiju in Jiangxi Province, China

Plants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 218
Author(s):  
Chingchai Chaisiri ◽  
Xiang-Yu Liu ◽  
Wei-Xiao Yin ◽  
Chao-Xi Luo ◽  
Yang Lin
Keyword(s):  
Phylogenetic Analyses ◽  
Citrus Fruit ◽  
Epidemiological Studies ◽  
Morphological Characterization ◽  
Jiangxi Province ◽  
Citrus Reticulata ◽  
Fruit Storage ◽  
Pathogenicity Tests ◽  
Rot Disease ◽  
Morphology Characterization

The Nanfengmiju (Citrus reticulata cv. Nanfengmiju), a high-quality local variety of mandarin, is one of the major fruit crops in Jiangxi Province, China. Citrus melanose and stem-end rot, two common fungal diseases of Nanfengmiju, are both caused by Diaporthe spp. (syn. Phomopsis spp.). Identification of the Diaporthe species is essential for epidemiological studies, quarantine measures, and management of diseases caused by these fungi. Melanose disease was observed on Nanfengmiju fruit in Jiangxi Province of China in 2016. Based on morphological characterization and multi-locus phylogenetic analyses, three out of 39 isolates from diseased samples were identified as D. passifloricola. Since these three isolates did not cause melanose on citrus fruit in the pathogenicity tests, they were presumed to be endophytic fungi present in the diseased tissues. However, our results indicate that D. passifloricola may persist as a symptom-less endophyte in the peel of citrus fruit, yet it may cause stem-end if it invades the stem end during fruit storage. To the best of our knowledge, this is the first report of D. passifloricola as the causal agent of the stem-end rot disease in Citrusreticulata cv. Nanfengmiju.

INCREASING CITRUS FRUIT SIZE USING AUXINS AND POTASSIUM.

1993 ◽  
pp. 112-119 ◽  
Author(s):  
Y. Erner ◽  
Y. Kaplan ◽  
B. Artzi ◽  
M. Hamou
Keyword(s):  
Fruit Size ◽  
Citrus Fruit

scholarly journals CITRUS FRUIT QUALITY CLASSIFICATION BASED ON SIZE USING DIGITAL IMAGE PROCESSING

2019 ◽  
Vol 48 (5) ◽  
pp. 95-101
Author(s):  
Ulzii-Orshikh Dorj ◽  
Uranbaigal Dejidbal ◽  
Hongseok Chae ◽  
Lkhagvadorj Batsambuu ◽  
Altanchimeg Badarch ◽  
...  
Keyword(s):  
Fruit Quality ◽  
Fruit Size ◽  
Citrus Fruit ◽  
Citrus Fruits ◽  
Single Tree ◽  
Quality Classification ◽  
Comparative Results ◽  
Vision Algorithm ◽  
Tree Fruits ◽  
Actual Size

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.

scholarly journals Leaf and Fruit Yield Performance of Telfairia occidentalis Hook F. (Fluted Pumpkin) as Influenced by Fruit Size

2014 ◽  
Vol 6 (4) ◽  
pp. 509-514 ◽  
Author(s):  
Uchechukwu Paschal CHUKWUDI ◽  
Christian Ugwu AGBO
Keyword(s):  
Block Design ◽  
Fruit Size ◽  
Fruit Weight ◽  
Fruit Yield ◽  
Cost Ratio ◽  
Environment Interaction ◽  
Yield Data ◽  
Fluted Pumpkin ◽  
Telfairia Occidentalis ◽  
Leaf Yield

An experiment to ascertain the influence of fruit size on the yield of fluted pumpkin (Telfairia occidentalis Hook F.) was conducted in 2011 and 2012 at Nsukka. The mature fruits of T. occidentalis were graded into three length groups: large (more than 50 cm), medium (34-50 cm) and small (less than 34 cm). The experiment was laid out in randomized complete block design with six replications. The following data were collected: length of the longest vine, number of leaves/plant, vine diameter, marketable leaf and fruit yield. Data collected were subjected to analysis of variance while Genotype by Genotype x Environment interaction biplot was used to show which-won-where among the groups. Significant means were separated using Fisher’s least significant differences. Medium sized fruits gave the highest marketable leaf yield that was significantly higher than the small sized fruits in both years. Small sized fruits were significantly (p<0.05) lower in total leaf yield, fruit weight/hectare, fruit circumference (33.9 cm) and length (22 cm). The biplot explained 100% of the variation in the fruit sizes. Large sized fruits were the best performer in fruit length, while medium sized fruits performed better in total marketable leaf yield, average fruit weight, number of fruits/hectare and total fruit weight/hectare. The highest Benefit Cost Ratio of 1.2 and 2.6 in 2011 and 2012, respectively were obtained from medium sized fruits Medium sized fruit are recommended in favour of small sized fruit for leaf and fruit production, having higher economic returns.

scholarly journals Beneficial Regulatory Effects of Polymethoxyflavone—Rich Fraction from Ougan (Citrus reticulata cv. Suavissima) Fruit on Gut Microbiota and Identification of Its Intestinal Metabolites in Mice

Antioxidants ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 831
Author(s):  
Jiebiao Chen ◽  
Yue Wang ◽  
Tailin Zhu ◽  
Sijia Yang ◽  
Jinping Cao ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
High Performance ◽  
Citrus Fruit ◽  
Intestinal Content ◽  
Citrus Reticulata ◽  
Citrus Fruits ◽  
Human Gut ◽  
16S Ribosomal Dna ◽  
Regulatory Effects ◽  
Main Components

Polymethoxyflavones (PMFs) are special flavonoids in citrus fruits that have been suggested to be beneficial to human health. However, whether PMFs in citrus fruit alter human gut microbiota is not well understood. The aim of the present study was to investigate the effects of PMF-rich fraction from Ougan (Citrus reticulata cv. Suavissima) on gut microbiota and evaluate the intestinal metabolic profile of PMFs in Institute of Cancer Research mice. The main components of the PMF-rich fraction were nobiletin, tangeretin, and 5-demethylnobiletin. The composition of the gut microbiota was analyzed using 16S ribosomal DNA sequencing. The results showed that after oral administration, the composition of mice gut microbiota was significantly altered. The relative abundance of two probiotics, Lactobacillus and Bifidobacterium, were found to increase significantly. A total of 21 metabolites of PMFs were detected in mice intestinal content by high performance liquid chromatography electrospray ionization tandem mass spectrometry, and they were generated through demethylation, demethoxylation, hydroxylation, and glucuronidation. Our results provided evidence that PMFs have potential beneficial regulatory effects on gut microbiota that in turn metabolize PMFs, which warrants further investigation in human clinical trials.

Increase in final fruit size of tangor ( Citrus reticulata × C. sinensis ) cv W. Murcott by application of benzyladenine to flowers

2017 ◽  
Vol 223 ◽  
pp. 38-43
Author(s):  
Carlos Ferrer ◽  
Johanna Martiz ◽  
Sebastian Saa ◽  
Ricardo Cautín
Keyword(s):  
Fruit Size ◽  
Citrus Reticulata

scholarly journals Interference of spray volume, fruit growth and rainfall on spray deposits in citrus black spot control periods

2016 ◽  
Vol 46 (5) ◽  
pp. 825-831 ◽  
Author(s):  
Demétrius de Araújo ◽  
Carlos Gilberto Raetano ◽  
Hamilton Humberto Ramos ◽  
Douglas Sampaio Ribeiro da Rocha ◽  
Evandro Pereira Prado ◽  
...  
Keyword(s):  
Spray Deposition ◽  
Control Period ◽  
Fruit Size ◽  
Citrus Fruit ◽  
Black Spot ◽  
Fruit Growth ◽  
Citrus Black Spot ◽  
Citrus Diseases ◽  
Significant Difference ◽  
Old Trees

ABSTRACT: Citrus black spot (CBS) caused by Guignardia citricarpa is one of the most serious Brazilian citrus diseases. This study aims to assess the interference of three application volumes in spray deposition citrus fruit, as well as fruit growth and rainfall effects on spray deposit reduction during the CBS control period. The experiment was carried out in a commercial citrus orchard, with sixteen-year-old trees of the Valencia variety, in Mogi Guaçu, São Paulo State, Brazil. The spray volumes were: 3.5 (1333L ha-1), 4.5 (1714L ha-1) and 8.5 (3238L ha-1) litres per tree, sprayed by an airblast sprayer using fungicides at recommended periods for disease control. The spray deposition quantification and residue was done by spectrophotometry using a copper oxychloride tracer. Samples were collected in three height zones of the tree (top, middle and bottom) and placed between trees on line plantation. Spray depositions were significantly smaller in the first application as a consequence of reduced fruit size. The spray losses on average for each day of rainfall ranged from 4.0 to 5.7%. There was no significant difference between application volumes regarding spray deposition on citrus fruit,which makes possible the reduction of application volumes, however, it is necessary to improve spraying techniques for the top zone of the citrus tree.

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