Russeting in Apple Is Initiated After Exposure to Moisture Ends—I. Histological Evidence

Russeting (periderm formation) is a critical fruit-surface disorder in apple (Malus × domestica Borkh.). The first symptom of insipient russeting is cuticular microcracking. Humid and rainy weather increases russeting. The aim was to determine the ontogeny of moisture-induced russeting in ‘Pinova’ apple. We recorded the effects of duration of exposure to water and the stage of fruit development at exposure on microcracking, periderm formation and cuticle deposition. Early on (21 or 31 days after full bloom; DAFB) short periods (2 to 12 d) of moisture exposure induced cuticular microcracking—but not later on (66 or 93 DAFB). A periderm was not formed during moisture exposure but 4 d after exposure ended. A periderm was formed in the hypodermis beneath a microcrack. Russeting frequency and severity were low for up to 4 d of moisture exposure but increased after 6 d. Cuticle thickness was not affected by moisture for up to 8 d but decreased for longer exposures. Cuticular ridge thickness decreased around a microcrack. In general, moisture did not affect cuticular strain release. We conclude that a hypodermal periderm forms after termination of moisture exposure and after microcrack formation. Reduced cuticle deposition may cause moisture-induced microcracking and, thus, russeting.

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Russeting in Apple is Initiated after Exposure to Moisture Ends: Molecular and Biochemical Evidence

Plants ◽

10.3390/plants10010065 ◽

2020 ◽

Vol 10 (1) ◽

pp. 65

Author(s):

Jannis Straube ◽

Yun-Hao Chen ◽

Bishnu P. Khanal ◽

Alain Shumbusho ◽

Viktoria Zeisler-Diehl ◽

...

Keyword(s):

Phase I ◽

Phase Ii ◽

Moisture Removal ◽

Full Bloom ◽

Gene Expressions ◽

Two Phases ◽

Cuticle Thickness ◽

Fruit Surface ◽

Wax Synthesis ◽

I 31

Exposure of the fruit surface to moisture during early development is causal in russeting of apple (Malus × domestica Borkh.). Moisture exposure results in formation of microcracks and decreased cuticle thickness. Periderm differentiation begins in the hypodermis, but only after discontinuation of moisture exposure. Expressions of selected genes involved in cutin, wax and suberin synthesis were quantified, as were the wax, cutin and suberin compositions. Experiments were conducted in two phases. In Phase I (31 days after full bloom) the fruit surface was exposed to moisture for 6 or 12 d. Phase II was after moisture exposure had been discontinued. Unexposed areas on the same fruit served as unexposed controls. During Phase I, cutin and wax synthesis genes were down-regulated only in the moisture-exposed patches. During Phase II, suberin synthesis genes were up-regulated only in the moisture-exposed patches. The expressions of cutin and wax genes in the moisture-exposed patches increased slightly during Phase II, but the levels of expression were much lower than in the control patches. Amounts and compositions of cutin, wax and suberin were consistent with the gene expressions. Thus, moisture-induced russet is a two-step process: moisture exposure reduces cutin and wax synthesis, moisture removal triggers suberin synthesis.

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Involvement of Aureobasidium pullulans and Rhodotorula glutinis in Russet of d'Anjou Pear Fruit

Plant Disease ◽

10.1094/pdis.2002.86.6.625 ◽

2002 ◽

Vol 86 (6) ◽

pp. 625-628 ◽

Cited By ~ 13

Author(s):

R. A. Spotts ◽

L. A. Cervantes

Keyword(s):

Aureobasidium Pullulans ◽

Rhodotorula Glutinis ◽

Pear Fruit ◽

Full Bloom ◽

Fruit Tissue ◽

History Of ◽

Fruit Surface

d'Anjou pear, the main cultivar grown in the Mid-Columbia Region of Oregon, is subject to russeting of the fruit surface, resulting in reduced quality and value. The role of Aureobasidium pullulans and Rhodotorula glutinis in russet of pear fruit was studied. Inoculations were done at full bloom in 1998 and 1999 and petal fall in 1999 with a log range of concentrations up to 108CFU/ml. Populations of A. pullulans on floral and fruit tissue were monitored during spring 1999 and 2000 in six orchards with a history of russet. Russet of fruit in both studies was evaluated at harvest. In 1998 neither fungus increased russet. In 1999, inoculation with two strains of each fungus at 108 CFU/ml increased russet. Inoculation with 104 or 106 CFU/ml did not increase russet in either year. In commercial orchards, there was no correlation between fruit russet and the populations of A. pullulans on floral and fruit tissue. Populations were less than 103 CFU/g of tissue. We conclude that A. pullulans and R. glutinis are not major contributors to russet of d'Anjou pear fruit in the Mid-Columbia Region.

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Absorption and Distribution of Calcium (45Ca) Applied to the Surface of Orange (Citrus sinensis) Fruits at Different Developmental Stages

Agronomy ◽

10.3390/agronomy12010150 ◽

2022 ◽

Vol 12 (1) ◽

pp. 150

Author(s):

Claudia Bonomelli ◽

Victoria Fernández ◽

Franco Capurro ◽

Carola Palma ◽

Ximena Videla ◽

...

Keyword(s):

Citrus Sinensis ◽

Fruit Set ◽

Developmental Stages ◽

The Other ◽

Full Bloom ◽

Sem Images ◽

Ca Transport ◽

Rate Of Absorption ◽

Fruit Surface ◽

Scanning Electron

In this study, the rate of absorption and transport of calcium (Ca) in orange fruits (Citrus sinensis cv. Fukumoto) after surface treatment with 45Ca was evaluated by supplying treatments at different dates between fruit set and mid-phase II of growth (i.e., 30, 44, 66 and 99 days after full bloom, DAFB). 45Ca absorption was always detected, but 45Ca application at the fruit set was associated with the highest rates of Ca transport into the pulp (39%) compared to the other treatments (17–19%). Scanning electron microscopy SEM) images of the fruit surface showed the occurrence of stomata along with the entire rind at all the developmental stages evaluated. However, from the beginning of stage I, stomata began to collapse and develop plugs, and this became frequent as the fruit age increased. From 44 DAFB, oil gland density increased, and Ca oxalates (CaOx) were found in the fruit flavedo and albedo. Fruit Ca (not labeled) concentration increased from fruit set (30 DAFB) to 99 DAFB, although oil gland formation and rind growth and differentiation likely hindered Ca transport to internal fruit tissues (pulp). The total Ca concentration in the pedicel was always higher than that in the fruit, with no differences between the first three treatments. The information obtained in this study may be essential for improving Ca fertilizer efficacy in citrus by spray applications.

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Russeting in ‘Apple’ Mango: Triggers and Mechanisms

Plants ◽

10.3390/plants9070898 ◽

2020 ◽

Vol 9 (7) ◽

pp. 898 ◽

Cited By ~ 2

Author(s):

Thomas O. Athoo ◽

Andreas Winkler ◽

Moritz Knoche

Keyword(s):

Water Vapour ◽

Cross Sections ◽

Dorsal Surface ◽

Dew Point ◽

Skin Area ◽

Surface Wetness ◽

Surface Disorder ◽

Growing Conditions ◽

Rating Scheme ◽

Periderm Formation

Russeting is an important surface disorder of many fruitcrop species. The mango cultivar ‘Apple’ is especially susceptible to russeting. Russeting compromises both fruit appearance and postharvest performance. The objective was to identify factors, mechanisms, and consequences of russeting in ‘Apple’ mango. Russeting was quantified on excised peels using image analysis and a categorical rating scheme. Water vapour loss was determined gravimetrically. The percentage of the skin area exhibiting russet increased during development. Russet began at lenticels then spread across the surface, ultimately forming a network of rough, brown patches over the skin. Cross-sections revealed stacks of phellem cells, typical of a periderm. Russet was more severe on the dorsal surface of the fruit than on the ventral and more for fruit in the upper part of the canopy than in the lower. Russet differed markedly across orchards sites of different climates. Russet was positively correlated with altitude, the number of rainy days, and the number of cold nights but negatively correlated with minimum, maximum, and mean daily temperatures, dew point temperature, and heat sum. Russeted fruit had higher transpiration rates than non-russeted fruits and higher skin permeance to water vapour. Russet in ‘Apple’ mango is due to periderm formation that is initiated at lenticels. Growing conditions conducive for surface wetness exacerbate russeting.

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The occurrence of a quiescent infection of stone fruits caused by Sclerotinia fructicola (wint.) Rehm.

Australian Journal of Agricultural Research ◽

10.1071/ar9650131 ◽

1965 ◽

Vol 16 (2) ◽

pp. 131 ◽

Cited By ~ 25

Author(s):

PT Jenkins ◽

C Reinganum

Keyword(s):

Fruit Ripening ◽

Circumstantial Evidence ◽

Field Observations ◽

Stone Fruits ◽

Ripe Fruit ◽

Growing Period ◽

Host Pathogen ◽

Periderm Formation ◽

Fruit Surface ◽

Pathogen Combinations

An infection of immature peach and apricot fruits by Sclerotinia fructicola (Wint.) Rehm. is described. Since infection results in macroscopically visible lesions it is proposed that this type of infection be known as "quiescent" rather than latent. Symptoms have been induced in immature apricots by inoculation with conidia of the fungus and, after a period of quiescence, progressive rots developed from such infections as the fruit ripened. The fungus was re-isolated from surface-sterilized material bearing quiescent infections. Cultural evidence, together with field observations, indicate that a quiescent infection occurs naturally in the orchard, particularly in a season of moderate to severe blossom infection. Fruit losses during a dry harvest period are ascribed in the main to the activation of quiescent infections during fruit ripening. The histology of the lesion is described. The response of the host to infection is variable, but always includes a more or less extensive collapse and necrosis of the epidermis and of one or more layers of the hypodermis. Periderm formation may be associated with the necrogenic reaction. The results of a spray trial demonstrate that some measure of control of quiescent infection can be achieved by applying eradicant sprays during blossoming, and thus provide circumstantial evidence that a proportion of such infections can be established during this period. The quiescent infection is compared with other host-pathogen combinations in which infection is followed by a period of latency or quiescence, and suggestions are put forward as to the factors governing quiescence. The concept of "latent contamination" is re-evaluated in the light of the evidence presented in the present paper. It is argued that conidia alighting on the fruit surface during the growing period are more likely to give rise to a quiescent infection than to survive to produce an infection of the ripe fruit.

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Emergence of size induced metallic state in the ferromagnetic insulating Pr0.8Sr0.2MnO3 manganite: Breaking of surface polarons

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v8i2.1517 ◽

2015 ◽

Vol 8 (2) ◽

pp. 2084-2093 ◽

Cited By ~ 2

Author(s):

PROLOY TARAN DAS ◽

Arun Kumar Nigam ◽

Tapan Kumar Nath

Keyword(s):

Transport Properties ◽

Metallic State ◽

Temperature Dependent ◽

Metal Insulator Transition ◽

Metal Insulator ◽

System A ◽

Surface Disorder ◽

Bulk System ◽

Magnetic Transport ◽

Grain Surface

Nano-dimensional effects on electronic-, magneto-transport properties of granular ferromagnetic insulating (FMI) Pr0.8Sr0.2MnO3 (PSMO) manganite (down to 40 nm) have been investigated in details. From the electronic and magnetic transport properties, a metallic state has been observed in grain size modulation by suppressing the ferromagnetic insulating state of PSMO bulk system. A distinct metal-insulator transition (MIT) temperature around 150 K has been observed in all nanometric samples. The observed insulator to metallic transition with size reduction can be explained with surface polaron breaking model, originates due to enhanced grain surface disorder. This proposed phenomenological polaronic model plays a significant role to understand the polaronic destabilization process on the grain surface regime of these phase separated nano-mangnatie systems. Temperature dependent resistivity and magnetoresistance data in presence of external magnetic fields are investigated in details with various compatible models.

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