Plants

Research

27 pages, 14927 KiB

Open AccessArticle

‘Honeycrisp’ Bitter Pit Response to Rootstock and Region under Eastern New York Climatic Conditions

by Daniel J. Donahue, Gemma Reig Córdoba, Sarah E. Elone, Anna E. Wallis and Michael R. Basedow

Plants 2021, 10(5), 983; https://doi.org/10.3390/plants10050983 - 14 May 2021

Cited by 13 | Viewed by 2482

There are still unknown factors at play in the causation of bitter pit in ‘Honeycrisp’ as well as in other apple varieties. To investigate some of these factors, we conducted a survey of 34 ‘Honeycrisp’ orchard blocks distributed across two disparate production regions [...] Read more.

There are still unknown factors at play in the causation of bitter pit in ‘Honeycrisp’ as well as in other apple varieties. To investigate some of these factors, we conducted a survey of 34 ‘Honeycrisp’ orchard blocks distributed across two disparate production regions in eastern New York State, representing a variety of rootstocks, over three growing seasons. Weather, soil, horticultural traits, fruit quality traits, pick timing, leaf and peel minerals were evaluated for their impact on bitter pit (BP) incidence; factors were further evaluated for their interaction with region and rootstock. ‘Honeycrisp’ trees on B.9 rootstock were smaller but with comparable terminal shoot growth when compared to those on M.26 and M.9 rootstocks. B.9 fruits, which had similar fruit size to M.26 and M.9 and had good fruit quality at harvest and after storage, were much less likely to express bitter pit symptoms compared to M.9 and M.26 rootstocks. Not all traits evaluated individually correlated significatively with bitter pit incidence after a period in storage. Depending on rootstock and region, the correlation could be significant in one situation, with no correlation at all in another. In this study, peel Mg/Ca ratio and peel Ca correlated with BP for all three rootstocks, with the strongest correlations associated with the M.9 clones. These same traits correlated with BP for both regions. Pick timing had a significant influence on BP incidence following storage, with later picks offering better bitter pit storage performance. While excessively large fruits, those in the 48 and 56 count size categories, were found to be highly susceptible to BP regardless of rootstock, B.9 BP fruit susceptibility for smaller sizes was found to be size neutral. A PLSR prediction model for each rootstock and each region showed that different variables correlated to BP depending on the situation. Thus, the results could suggest that in addition to the variables considered in this study, there are other less studied factors that can influence the expression of BP symptoms. We strongly suggest that rootstock BP performance be considered a critical parameter when planning a commercial ‘Honeycrisp’ orchard and be evaluated in rootstock breeding and development programs prior to wide commercial release. Full article

(This article belongs to the Special Issue Physiological Responses of Tree Fruits to Environmental and Management Factors)

► Show Figures

Figure 1

15 pages, 1673 KiB

Open AccessArticle

Soil and Regulated Deficit Irrigation Affect Growth, Yield and Quality of ‘Nero d’Avola’ Grapes in a Semi-Arid Environment

by Maria Gabriella Barbagallo, Giuseppe Vesco, Rosario Di Lorenzo, Riccardo Lo Bianco and Antonino Pisciotta

Plants 2021, 10(4), 641; https://doi.org/10.3390/plants10040641 - 28 Mar 2021

Cited by 16 | Viewed by 3040

Abstract

The present work studied the effect of two consecutive years of regulated deficit irrigation (RDI) compared to rain fed management on the vegetative growth, yield, and quality of ‘Nero d’Avola’ grapes. The trial was conducted separately in two soils (vertisol and entisol) located [...] Read more.

The present work studied the effect of two consecutive years of regulated deficit irrigation (RDI) compared to rain fed management on the vegetative growth, yield, and quality of ‘Nero d’Avola’ grapes. The trial was conducted separately in two soils (vertisol and entisol) located at the top and bottom hillside of the same vineyard. Vertisol was characterized by greater depth, organic matter, exchangeable K₂O, and total N than entisol. RDI was based on an irrigation volume at 25% of estimated crop evapotranspiration (ET_c) up to end of veraison and 10% of estimated ET_c up to 15 days before harvest. Predawn water potential (PDWP) was used as indicator of plant water status and irrigation timing. No difference in irrigation management was evident between vertisol and entisol. Under Mediterranean climate conditions, RDI was able to enhance grape yield and vegetative growth, especially in vertisol, but it reduced berry titratable acidity and total anthocyanins. ‘Nero d’Avola’ showed to adapt to drought conditions in the open field. Both soil type and irrigation regimes may provide opportunities to obtain different ‘Nero d’Avola’ wine quality and boost typicality. Full article

(This article belongs to the Special Issue Physiological Responses of Tree Fruits to Environmental and Management Factors)

► Show Figures

Figure 1

Figure 1
Seasonal variation (DOY, day of the year) in predawn leaf water potential (PDWP) of ‘Nero d’Avola’ grapevines grown in two soils (entisol and vertisol) under rain-fed and regulated deficit irrigation (RDI) treatments in 2005 (A) and 2006 (B). Bars show rainfall and irrigation events. Cumulative ET0 is shown from pea size phenological stage (DOY 160) to ten days before harvest (DOY 245). In 2006, the irrigation started at the end of July (DOY 206). Error bars indicate standard errors (n = 12). Dashed horizontal lines indicate the PDWP threshold values for irrigation. When present, different letters indicate significant differences among treatments for a specific date (Tukey’s multiple range test, p < 0.05). Full article ">Figure 2
Variation of soil water content (%) over the season in two soils (vertisol and entisol) (A) and irrigation treatments (regulated deficit irrigation (RDI), and rain-fed) (B). Error bars indicate standard errors (n = 24); DOY, day of the year. When present, asterisks indicate significant differences between means (Tukey’s test, p < 0.05). Full article ">Figure 3
Variation in stem water potential (SWP) of ‘Nero d’Avola’ grapevines grown in two soils (entisol and vertisol) under rain-fed and regulated deficit irrigation (RDI) treatments in 2005 (A) and 2006 (B). In 2006, the irrigation started at the end of July (DOY 206). Error bars indicate standard errors (n = 12). When present, different letters indicate significant differences among treatments for a specific date (Tukey’s multiple range test, p < 0.05). Full article ">Figure 4
Relationships between stomatal conductance (gs) and predawn leaf water potential (PDWP) of ‘Nero d’Avola’ vines grown in two soils (entisol and vertisol) under rain-fed conditions in 2005 (A) and 2006 (B), and under regulated deficit irrigation (RDI) in 2005 (C) and 2006 (D). Each point is the mean of four measurements. Data from the two soil types were similar (t-test of coefficients, p < 0.05) and pooled together for each year and irrigation treatment. Full article ">Figure 5
Relationships between stem water potential (SWP) and stomatal conductance (gs) of ‘Nero d’Avola’ vines grown in two soils (entisol and vertisol) under rain-fed conditions in 2005 (A) and 2006 (B), and under regulated deficit irrigation (RDI) in 2005 (C) and 2006 (D). Each point is the mean of four measurements. Data from the two soil types were similar (t-test of coefficients, p < 0.05) and pooled together for each year and irrigation treatment. Full article ">Figure 6
Difference in total leaf area from pea size to harvest (average of two years) for ‘Nero d’Avola’ vines grown in two soils (entisol and vertisol) and under rain-fed and regulated deficit irrigation (RDI) treatments. Full article ">

16 pages, 694 KiB

Open AccessArticle

Modelling Soluble Solids Content Accumulation in ‘Braeburn’ Apples

by Konni Biegert, Daniel Stöckeler, Roy J. McCormick and Peter Braun

Plants 2021, 10(2), 302; https://doi.org/10.3390/plants10020302 - 5 Feb 2021

Cited by 12 | Viewed by 3161

Abstract

Optical sensor data can be used to determine changes in anthocyanins, chlorophyll and soluble solids content (SSC) in apple production. In this study, visible and near-infrared spectra (729 to 975 nm) were transformed to SSC values by advanced multivariate calibration models i.e., partial [...] Read more.

Optical sensor data can be used to determine changes in anthocyanins, chlorophyll and soluble solids content (SSC) in apple production. In this study, visible and near-infrared spectra (729 to 975 nm) were transformed to SSC values by advanced multivariate calibration models i.e., partial least square regression (PLSR) in order to test the substitution of destructive chemical analyses through non-destructive optical measurements. Spectral field scans were carried out from 2016 to 2018 on marked ‘Braeburn’ apples in Southwest Germany. The study combines an in-depth statistical analyses of longitudinal SSC values with horticultural knowledge to set guidelines for further applied use of SSC predictions in the orchard to gain insights into apple carbohydrate physiology. The PLSR models were investigated with respect to sample size, seasonal variation, laboratory errors and the explanatory power of PLSR models when applied to independent samples. As a result of Monte Carlo simulations, PLSR modelled SSC only depended to a minor extent on the absolute number and accuracy of the wet chemistry laboratory calibration measurements. The comparison between non-destructive SSC determinations in the orchard with standard destructive lab testing at harvest on an independent sample showed mean differences of 0.5% SSC over all study years. SSC modelling with longitudinal linear mixed-effect models linked high crop loads to lower SSC values at harvest and higher SSC values for fruit from the top part of a tree. Full article

(This article belongs to the Special Issue Physiological Responses of Tree Fruits to Environmental and Management Factors)

► Show Figures

Figure 1

Figure 1
Soluble solids content (SSC) accumulation derived from the yearly calibrated (<a href="#sec2dot1dot1-plants-10-00302" class="html-sec">Section 2.1.1</a>) partial least squares regression models (a) and fruit diameter growth (b) for the three study years and all treatments are shown. Mean values per measurement day are plotted as solid line, single values as grey dots and +/−standard deviations as black vertical bars. Full article ">Figure 2
Regressions between laboratory measured and modelled % SSC. The calibration model was trained on 2016–2018 data. This model was thereafter evaluated with an independent validation data set for all years together and separately. Regression lines are plotted for each validation data set and adjusted prediction <math display="inline"><semantics> <msup> <mi>R</mi> <mn>2</mn> </msup> </semantics></math> is displayed.Diagnostic plots Full article ">Figure 3
Root mean square error of prediction (RMSEP) in % soluble solids content (SSC) based on 2016, 2017 and 2018 partial least squares regression (PLSR) models to test the effect of reduced calibration sample sets. For each setting, 500 Monte Carlo simulation runs were performed. Mean and standard deviation for each point are shown and 500 observations in each calibration data set and 100 observations in each validation data set used. Full article ">Figure 4
Root mean square error of prediction (RMSEP) in % soluble solids content (SSC) based on 2016, 2017 and 2018 partial least squares regression (PLSR) models to test for nonsystematic laboratory errors during wet chemistry analyses. For each setting, 500 Monte Carlo simulation runs were performed. Mean and standard deviation for each point are shown and 500 observations in each calibration data set and 100 observations in each validation data set used. Full article ">

16 pages, 3634 KiB

Open AccessFeature PaperArticle

Detecting Mild Water Stress in Olive with Multiple Plant-Based Continuous Sensors

by Giulia Marino, Alessio Scalisi, Paula Guzmán-Delgado, Tiziano Caruso, Francesco Paolo Marra and Riccardo Lo Bianco

Plants 2021, 10(1), 131; https://doi.org/10.3390/plants10010131 - 11 Jan 2021

Cited by 26 | Viewed by 3995

Abstract

A comprehensive characterization of water stress is needed for the development of automated irrigation protocols aiming to increase olive orchard environmental and economical sustainability. The main aim of this study is to determine whether a combination of continuous leaf turgor, fruit growth, and [...] Read more.

A comprehensive characterization of water stress is needed for the development of automated irrigation protocols aiming to increase olive orchard environmental and economical sustainability. The main aim of this study is to determine whether a combination of continuous leaf turgor, fruit growth, and sap flow responses improves the detection of mild water stress in two olive cultivars characterized by different responses to water stress. The sensitivity of the tested indicators to mild stress depended on the main mechanisms that each cultivar uses to cope with water deficit. One cultivar showed pronounced day to day changes in leaf turgor and fruit relative growth rate in response to water withholding. The other cultivar reduced daily sap flows and showed a pronounced tendency to reach very low values of leaf turgor. Based on these responses, the sensitivity of the selected indicators is discussed in relation to drought response mechanisms, such as stomatal closure, osmotic adjustment, and tissue elasticity. The analysis of the daily dynamics of the monitored parameters highlights the limitation of using non-continuous measurements in drought stress studies, suggesting that the time of the day when data is collected has a great influence on the results and consequent interpretations, particularly when different genotypes are compared. Overall, the results highlight the need to tailor plant-based water management protocols on genotype-specific physiological responses to water deficit and encourage the use of combinations of plant-based continuously monitoring sensors to establish a solid base for irrigation management. Full article

(This article belongs to the Special Issue Physiological Responses of Tree Fruits to Environmental and Management Factors)

► Show Figures

Figure 1

Figure 1
Example of the stress phases based on the inversion of the leaf patch clamp probe (LPCP) output pressure (Pp) reading, with the green area showing the phase 1 or no stress (no inversion of the Pp curve, Pp equal to the inverse of turgor pressure); the yellow area indicating phase 2 or stress onset (half-inversion of the Pp curves or semi-inversion) and the red area showing phase 3 or high stress (full inversion of the Pp curve). Dark blue vertical lines indicate midnight and light blue dashed vertical lines indicate midday. Full article ">Figure 2
Seasonal trend of vapor pressure deficit (VPD, hourly mean) and total daily rain (from hourly values) from 1 August to 26 September 2015, obtained from data of the meteorological station in Sciacca, Sicily, Italy. Full article ">Figure 3
Weekly midday stem water potential (Ψstem) measured for the olive cultivars Olivo di Mandanici (OM) and Nocellara del Belice (NB). Vertical black bars represent standard errors of the mean (n = 9); asterisks indicate significant differences between means (Tukey’s test, p ≤ 0.05). Full article ">Figure 4
Time course of the hourly standardized leaf patch clamp pressure (LPCP) probe output pressure (Pp) for the olive cultivars Olivo di Mandanici (a) and Nocellara del Belice (b). Green, yellow and red dots represent daily stress phases based on exploratory data analysis of the diurnal shape of the LPCP probe outputs: phase 1 or no stress (no inversion of the Pp curve); phase 2 or stress onset (half-inversion of the Pp curves), and phase 3 or high stress (full inversion of the Pp curve). The horizontal dotted lines are the z-score of −1 and +1, representing the thresholds within which 68.27% of the results fall. Red arrows highlight the variability of the Pp values between irrigation events discussed in the text. Full article ">Figure 5
Time course of the hourly fruit relative growth rate (RGR) for the olive cultivars Olivo di Mandanici (a) and Nocellara del Belice (b). Red arrows indicate the trends of RGR peaks between consecutive irrigation events discussed in the text. Full article ">Figure 6
Time course of the hourly sap flow rate (Q) for the olive cultivars Olivo di Mandanici (a) and Nocellara del Belice (b). Full article ">Figure 7
Relationships between midday stem water potential (Ψstem) and the daily minimum leaf patch clamp pressure (LPCP) probe outputs value (Pp-min, z-scores, panel a), difference between daily minimum and maximum relative growth rate (RGRrange, panel b), and the daily average of hourly sap flow rate (Qave, panel c) in the olive cultivars Olivo di Mandanici (OM, solid lines) and Nocellara del Belice (NB, dashed line). Full article ">Figure 8
Hourly trends of (a) sap flow rate (Q), (b) standardized leaf patch clamp probe outputs (1 − Pp) and (c) fruit relative growth rate (RGR) for the olive cultivars Nocellara del Belice (NB) and Olivo di Mandanici (OM) between two consecutive irrigation events, from 15 to 21 August. T1, T2 T3, and T4 represent key timeframes described in the text. Full article ">

16 pages, 4492 KiB

Open AccessArticle

Red and Blue Netting Alters Leaf Morphological and Physiological Characteristics in Apple Trees

by Richard M. Bastías, Pasquale Losciale, Camilla Chieco and Luca Corelli-Grappadelli

Plants 2021, 10(1), 127; https://doi.org/10.3390/plants10010127 - 9 Jan 2021

Cited by 14 | Viewed by 3502

Abstract

There is little information about the role of red and blue light on leaf morphology and physiology in fruit trees, and more studies have been developed in herbaceous plants grown under controlled light conditions. The objective of this research was to evaluate the [...] Read more.

There is little information about the role of red and blue light on leaf morphology and physiology in fruit trees, and more studies have been developed in herbaceous plants grown under controlled light conditions. The objective of this research was to evaluate the effect of red and blue screens on morpho-anatomy and gas exchange in apple leaves grown under ambient sunlight conditions. Apple trees cv. Fuji were covered by 40% red and blue nets, leaving trees with 20% white net as control. Light relations (photosynthetic photon flux density, PPFD; red to far-red light ratio, R/FR and blue to red light ratio, B/R), morpho-anatomical features of the leaf (palisade to spongy mesophyll ratio, P/S, and stomata density, SD) and leaf gas exchange (net photosynthesis rate, A_n; stomatal conductance, g_s; transpiration rate, E; and intrinsic water use efficiency, IWUE) were evaluated. Red and blue nets reduced 27% PPFD, reducing by 20% SD and 25% P/S compared to control, but without negative effects on A_n and g_s. Blue net increased g_s 21%, leading to the highest E and lowest IWUE by increment of B/R light proportion. These findings demonstrate the potential use of red and blue nets for differential modulation of apple leaf gas exchange through sunlight management under field conditions. Full article

(This article belongs to the Special Issue Physiological Responses of Tree Fruits to Environmental and Management Factors)

► Show Figures

Figure 1

23 pages, 7091 KiB

Open AccessArticle

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

by Jannis Straube, Yun-Hao Chen, Bishnu P. Khanal, Alain Shumbusho, Viktoria Zeisler-Diehl, Kiran Suresh, Lukas Schreiber, Moritz Knoche and Thomas Debener

Plants 2021, 10(1), 65; https://doi.org/10.3390/plants10010065 - 30 Dec 2020

Cited by 24 | Viewed by 4483

Abstract

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 [...] Read more.

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. Full article

(This article belongs to the Special Issue Physiological Responses of Tree Fruits to Environmental and Management Factors)

► Show Figures

Figure 1

15 pages, 1581 KiB

Open AccessArticle

Gibberellic Acid Modifies the Transcript Abundance of ABA Pathway Orthologs and Modulates Sweet Cherry (Prunus avium) Fruit Ripening in Early- and Mid-Season Varieties

by Nathalie Kuhn, Claudio Ponce, Macarena Arellano, Alson Time, Boris Sagredo, José Manuel Donoso and Lee A. Meisel

Plants 2020, 9(12), 1796; https://doi.org/10.3390/plants9121796 - 18 Dec 2020

Cited by 21 | Viewed by 3764

Abstract

Several phytohormones modulate ripening in non-climacteric fruits, which is triggered by abscisic acid (ABA). Gibberellins (GAs) are present during the onset of ripening in sweet cherry fruits, and exogenous gibberellic acid (GA₃) application delays ripening, though this effect is variety-dependent. Although [...] Read more.

Several phytohormones modulate ripening in non-climacteric fruits, which is triggered by abscisic acid (ABA). Gibberellins (GAs) are present during the onset of ripening in sweet cherry fruits, and exogenous gibberellic acid (GA₃) application delays ripening, though this effect is variety-dependent. Although an ABA accumulation delay has been reported following GA₃ treatment, the mechanism by which GA modulates this process has not been investigated at the molecular level in sweet cherry. Therefore, the aim of this work is to analyze the effect of GA₃ on the fruit ripening process and the transcript levels of ABA pathway orthologs in two varieties having different maturity time phenotypes. The early-season variety had a rapid transition from yellow to pink fruit color, whereas pink color initiation took longer in the mid-season variety. GA₃ increased the proportion of lighter colored fruits at ripeness in both varieties, but it produced a delay in IAD—a ripening index—only in the mid-season variety. This delay was accompanied by an increased transcript abundance of PavPP2Cs, which are putative negative regulators of the ABA pathway. On the other hand, the early-season variety had increased expression of PavCYP707A2—a putative ABA catabolic gene–, and reduced transcript levels of PavPP2Cs and SnRK2s after the GA₃ treatment. Together these results show that GA modulates fruit ripening, exerting its action in part by interacting with the ABA pathway in sweet cherry. Full article

(This article belongs to the Special Issue Physiological Responses of Tree Fruits to Environmental and Management Factors)

► Show Figures

Figure 1

Figure 1
Fruit growth and growth rate curves of early-season variety, Glenred (A) and mid-season variety, Lapins (B). A color scale is included based on fruit phenology (<a href="#app1-plants-09-01796" class="html-app">Tables S1 and S2</a>). Growth resumption prior to fruit color change is indicated with a dotted blue line, 20 fruits from Lapins and Glenred were randomly selected for measurements. Data as ± SEM. DAFB, days after full bloom. Full article ">Figure 2
Effect of exogenous gibberellic acid (GA3) on fruit growth of early-season variety, Glenred (A) and mid-season variety, Lapins (B) 20 fruits from control and GA3 trees of Lapins and Glenred were randomly selected for measurements. Data as ± SEM ANOVA with Tukey’s post hoc test at p < 0.05 was conducted; “*” denotes statistical differences between GA3-treated and control fruits. DAFB, days after full bloom. Full article ">Figure 3
Effect of GA3 on color distribution and index of absorbance difference (IAD) at harvest of early-season variety, Glenred (A,B) and mid-season variety, Lapins (C,D). 20 fruits from control and GA3 trees of Lapins and Glenred were randomly selected for nondestructive IAD measurements in the field and 25 fruits for color distribution assessment at harvest. Data as ± SEM ANOVA with Tukey’s post hoc test at p < 0.05 was conducted; “*” denotes statistical differences between GA3-treated and control fruits CTIFL (Centre Technique Interprofessionnel des Fruits et Légumes) color chart was used in (B,D), where 1 is the lightest color, and 4 is the darkest color, respectively (<a href="#app1-plants-09-01796" class="html-app">Figure S3</a>). DAFB, days after full bloom. Full article ">Figure 4
Effect of GA3 on transcript abundance relative to PavCAC of PavNCED1 and PavCYP707A2 sweet cherry orthologs, 5 days after the treatment (T5). Fruits from control and GA3 trees of (A) early-season variety Glenred and (B) mid-season variety Lapins, were randomly selected and pooled for the RT–qPCR analyses. Data as +SEM. Relative transcript abundance was set to 1.0 at T0, where T0 is the sampling performed immediately before GA3 application ANOVA with Tukey’s post hoc test at p < 0.05 was conducted; “*” denotes statistical differences between GA3-treated and control fruits for a gene. Full article ">Figure 5
Effect of GA3 on transcript abundance relative to PavCAC of PavPP2C and PavSnRK2 sweet cherry orthologs, 5 days after the treatment (T5). Fruits from control and GA3 trees of (A) early-season variety Glenred and (B) mid-season variety Lapins were randomly selected and pooled for the RT–qPCR analyses. Data as +SEM. Relative transcript abundance was set to 1.0 at T0, where T0 is the sampling performed immediately before GA3 application ANOVA with Tukey’s post hoc test at p < 0.05 was conducted; “*” denotes statistical differences between GA3-treated and control fruits for a gene. Full article ">

21 pages, 2109 KiB

Open AccessEditor’s ChoiceArticle

Correction of Potassium Fertigation Rate of Apple Tree (Malus domestica Borkh.) in Central Russia during the Growing Season

by Andrei I. Kuzin, Natalia Ya. Kashirskaya, Anna M. Kochkina and Alexey V. Kushner

Plants 2020, 9(10), 1366; https://doi.org/10.3390/plants9101366 - 15 Oct 2020

Cited by 28 | Viewed by 3694

Abstract

The proper use of potassium fertilizer can stimulate a significant yield increase. However, the application of excessively high rates of potassium can reduce the availability of soil calcium for apple trees. The potassium fertigation rate must meet the apple tree’s requirements so that [...] Read more.

The proper use of potassium fertilizer can stimulate a significant yield increase. However, the application of excessively high rates of potassium can reduce the availability of soil calcium for apple trees. The potassium fertigation rate must meet the apple tree’s requirements so that the applied fertilizers can be absorbed by the roots as much as possible. Crop load in apple orchards sometimes varies significantly in different years. The potassium content in apple fruits is relatively high, and the maximum requirement for this nutrient occurs when fruits grow and ripen. Different crop loads at that time mean the various demands of trees and need for changing application rates for this nutrient. The investigation was carried out in the experimental orchard of I.V. Michurin Federal Scientific Centre (Michurinsk, Russia) in 2016 and 2017 (52.885131, 40.465613). We studied seasonal changes of potassium and calcium contents in soil, fruits, and leaves and their relationship with yield during the research. We paid much attention to the potassium rate shift on its content in leaves and fruits and cultivars “Lobo” and “Zhigulevskoye” yield. If the potassium application rate changes according to the actual crop load, it stimulates the yield growth or (if the crop load was relatively low) the reduction of the rate did not lower the productivity. Moreover, we studied the relationship between potassium and calcium nutrition. The decrease in potassium fertigation rate increased the availability of soil calcium. It was the reason for fruit calcium concentration enlargement and mitigation of the K/Ca ratio. We also specified some parameters for soil–leaf diagnosis for potassium nutrition during the growing season. Full article

(This article belongs to the Special Issue Physiological Responses of Tree Fruits to Environmental and Management Factors)

► Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
Seasonal changes of the soil exchangeable potassium content, cv. “Zhigulevskoye” plots: (a) 2016 and (b) 2017 (only G1 unchangeable K rates). Full article ">Figure 2
Seasonal changes of the soil exchangeable potassium content, cv. “Lobo” plots: (a) 2016 and (b) 2017 (only G1 unchangeable K rates). Full article ">Figure 3
Dynamic changes of correlation coefficients between the potassium leaf status and yield in growing season 2016: (a) cv. “Zhigulevskoye”; (b) cv. “Lobo”. Full article ">Figure 4
Dynamic changes of correlation coefficients between the potassium leaf status and yield in growing season 2017: (a) cv. “Zhigulevskoye”; (b) cv. “Lobo”. Full article ">Figure 5
Dynamic changes of correlation coefficients between the leaf calcium status and potassium fertigation rates during the growing season of 2016: (a) cv. “Zhigulevskoye”; (b) cv. “Lobo”. Full article ">Figure 6
Dynamic changes of correlation coefficients between the leaf calcium status and potassium fertigation rates during the growing season of 2017. (a) cv. “Zhigulevskoye”; (b) cv. “Lobo”. Full article ">

10 pages, 1670 KiB

Open AccessArticle

The Influence of Environmental Features on the Morphometric Variation in Mauritia flexuosa L.f. Fruits and Seeds

by Nilo L. Sander, Carolina J. da Silva, Aline V. M. Duarte, Bruno W. Zago, Carla Galbiati, Iris G. Viana, Joari C. de Arruda, Juliana E. Dardengo, Juliana P. Poletine, Marcelo H. Siqueira Leite, Marta H. S. de Souza, Robson F. de Oliveira, Thallita S. Guimarães, Valvenarg P. da Silva and Marco A. A. Barelli

Plants 2020, 9(10), 1304; https://doi.org/10.3390/plants9101304 - 2 Oct 2020

Cited by 7 | Viewed by 2657

Abstract

The environmental heterogeneity may reflect the different morphological and phenotypic traits of individuals belonging to a single species. We used 14 morphological traits of Mauritia flexuosa L.f. to understanding the relation between environment and phenotypic traits. Twenty-five fruits were collected from each of [...] Read more.

The environmental heterogeneity may reflect the different morphological and phenotypic traits of individuals belonging to a single species. We used 14 morphological traits of Mauritia flexuosa L.f. to understanding the relation between environment and phenotypic traits. Twenty-five fruits were collected from each of the 10 individuals sampled in each study site: Chapada dos Guimarães (CG), Vila Bela da Santíssima Trindade (VB), and Alta Floresta (AF). We analyzed the genetic divergence, using the standardized Euclidean distance, the sequential method of Tocher, unweighted pair group method with arithmetic mean (UPGMA), and the projection of the distances onto 2D plane, and calculated the relative importance of the traits evaluated. The analysis showed the partition of individuals into three main groups: Two groups comprising the majority of individuals. Fresh fruit weight, pulp rate, fresh pulp weight, and moisture rate were the traits that most helped explaining the difference between materials. The results shown in the current study evidenced the influence of these three different environments on the biometric traits of M. flexuosa. Such influence has led to the formation of Alta Floresta and Vila Bela da Santíssima Trindade individuals in different groups, whereas the Chapada dos Guimarães individuals were able to permeate the two other groups, although they showed stronger tendency to group with individuals from Vila Bela da Santíssima Trindade. Full article

(This article belongs to the Special Issue Physiological Responses of Tree Fruits to Environmental and Management Factors)

► Show Figures

Figure 1

18 pages, 8504 KiB

Open AccessArticle

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

by Yun-Hao Chen, Jannis Straube, Bishnu P. Khanal, Moritz Knoche and Thomas Debener

Plants 2020, 9(10), 1293; https://doi.org/10.3390/plants9101293 - 30 Sep 2020

Cited by 26 | Viewed by 3628

Abstract

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. [...] Read more.

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. Full article

(This article belongs to the Special Issue Physiological Responses of Tree Fruits to Environmental and Management Factors)

► Show Figures

Figure 1

20 pages, 2665 KiB

Open AccessArticle

Gaining Insight into Exclusive and Common Transcriptomic Features Linked to Drought and Salinity Responses across Fruit Tree Crops

by Jubina Benny, Annalisa Marchese, Antonio Giovino, Francesco Paolo Marra, Anna Perrone, Tiziano Caruso and Federico Martinelli

Plants 2020, 9(9), 1059; https://doi.org/10.3390/plants9091059 - 19 Aug 2020

Cited by 14 | Viewed by 3585

Abstract

The present study aimed at identifying and mapping key genes expressed in root tissues involved in drought and salinity tolerance/resistance conserved among different fruit tree species. Twenty-six RNA-Seq samples were analyzed from six published studies in five plant species (Olea europaea, Vitis [...] Read more.

The present study aimed at identifying and mapping key genes expressed in root tissues involved in drought and salinity tolerance/resistance conserved among different fruit tree species. Twenty-six RNA-Seq samples were analyzed from six published studies in five plant species (Olea europaea, Vitis riparia Michx, Prunus mahaleb, Prunus persica, Phoenix dactylifera). This meta-analysis used a bioinformatic pipeline identifying 750 genes that were commonly modulated in three salinity studies and 683 genes that were commonly regulated among three drought studies, implying their conserved role in resistance/tolerance/response to these environmental stresses. A comparison was done on the genes that were in common among both salinity and drought resulted in 82 genes, of which 39 were commonly regulated with the same trend of expression (23 were upregulated and 16 were downregulated). Gene set enrichment and pathway analysis pointed out that pathways encoding regulation of defense response, drug transmembrane transport, and metal ion binding are general key molecular responses to these two abiotic stress responses. Furthermore, hormonal molecular crosstalk plays an essential role in the fine-tuning of plant responses to drought and salinity. Drought and salinity induced a different molecular “hormonal fingerprint”. Dehydration stress specifically enhanced multiple genes responsive to abscisic acid, gibberellin, brassinosteroids, and the ethylene-activated signaling pathway. Salt stress mostly repressed genes encoding for key enzymes in signaling proteins in auxin-, gibberellin-(gibberellin 2 oxidase 8), and abscisic acid-related pathways (aldehyde oxidase 4, abscisic acid-responsive element-binding protein 3). Abiotic stress-related genes were mapped into the chromosome to identify molecular markers usable for the improvement of these complex quantitative traits. This meta-analysis identified genes that serve as potential targets to develop cultivars with enhanced drought and salinity resistance and/or tolerance across different fruit tree crops in a biotechnological sustainable way. Full article

(This article belongs to the Special Issue Physiological Responses of Tree Fruits to Environmental and Management Factors)

► Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
Drought- and salinity-regulated genes involved in hormone-related categories commonly regulated in the studies are shown. Genes were identified as Arabidopsis orthologs of each gene of the analyzed plant species. Red and green indicate the up- and down-regulated genes in drought, whereas blue and yellow indicate the up- and down-regulated genes in salinity. Full article ">Figure 2
Drought/salinity-regulated genes involved in abiotic stress-related categories commonly regulated in all eight studies are indicated. Genes were identified as Arabidopsis thaliana orthologs of each gene of the analyzed plant species. Red indicates up-regulation and green indicates down-regulation in response to drought stress, whereas blue and yellow indicate up- and down-regulated genes in salinity. Full article ">Figure 3
Protein–protein interaction network analysis predicted for genes commonly regulated in (a) three of three drought studies, and (b) three of three salinity studies; (c) genes commonly regulated in six of six studies of both drought and salinity based on Arabidopsis knowledgebase. Proteins encoded by genes having a high degree of betweenness are shown in red (up-regulated) and green (down-regulated). Full article ">Figure 4
Main gene regulatory networks in common between responses to drought and salinity. Key genes involved in hormonal signaling, transduction signal, transcription regulation, and defense responses identified by the meta-analysis are indicated together with physiological effects. Upregulated genes are shown in red, while downregulated genes are shown in green. Full article ">Figure 5
Workflow of the meta-analysis of the six transcriptomic studies related to drought and salinity stress in root tissue. Functional and statistical data analysis are indicated. Full article ">

18 pages, 3303 KiB

Open AccessArticle

Russeting in ‘Apple’ Mango: Triggers and Mechanisms

by Thomas O. Athoo, Andreas Winkler and Moritz Knoche

Plants 2020, 9(7), 898; https://doi.org/10.3390/plants9070898 - 16 Jul 2020

Cited by 18 | Viewed by 10680

Abstract

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 [...] Read more.

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. Full article

(This article belongs to the Special Issue Physiological Responses of Tree Fruits to Environmental and Management Factors)

► Show Figures

Figure 1

Figure 1
Macroscope view of mature ‘Apple’ mango without (a, score 0), moderate (b, score 2), and extreme (c, score 4) russet symptoms. (d): Plot of russeting (rating score) against percentage area affected by russet (image analysis). Each fruit was rated visually prior to image analysis. The number of observations was 18. Full article ">Figure 2
Change in fruit surface area (cm2) and rate of surface expansion (a and a inset) with time (days after full bloom, DAFB). Percent of skin with russet in developing fruit (b) calculated from a defined area of the fruit cheek. The same fruit was photographed at 100, 156, and 216 DAFB (see arrows). Pictorial representation of russet progression in a developing ‘Apple’ mango fruit (c1–c3). Scale bar is 10 mm. Data represent means ± SE of 19 replicates. Full article ">Figure 3
Microscopic view of ‘Apple’ mango skin infiltrated with acridine orange dye when viewed with a binocular microscope under natural (a,c,e,g,i,k,m) or fluorescent light (b,d,f,h,j,l,n). The scale bars refer to the corresponding pairs of images. Full article ">Figure 4
Cross-sectional microscope images of a non-russeted (a,b) and russeted (c–j) skin of ‘Apple’ mango viewed under incident white (a,c,e,g,i) or fluorescent light (b,d,f,h,j) following staining with fluorol yellow dye. Scale bar is 50 µm. Full article ">Figure 5
Relationship between climatic variables and average russeting (rating score) determined for the cumulative period of fruit maturity at ten locations in Kenya. The ten locations were: Garissa (1), Chepsigot (2), Malindi (3), Mumbuni (4), Yeemulwa (5), Kaiti (6), Kasafari (7), Kambirwa (8), Thika (9), and Machakos (10) situated at different altitudes. (a) The climatic variables include: rainfall amount (b), days with rainfall (c), relative humidity (d), minimum, maximum, and mean daily temperatures (e, f, and g, respectively). Cold nights (h) correspond to the number of days when the minimum temperature fell below the base temperature of 16 °C. Heat sum (i) was calculated based on a base temperature of 16 °C. Russeting was quantified using a five-score rating scheme: score 0: 0% of the fruit surface area russeted; score 1: 1–10% russeted area; score 2: 11–25% russeted area; score 3: 26–50% russeted area; and score 4: 51–100% russeted area. Data points represent means of 210 fruit per site. Full article ">Figure 6
Time course of transpiration by whole fruits with extreme (>50%) (russeted) and with minimal (<25%) russet (not russeted) (a) and through epidermal sections (ES) excised from the cheek of mature ‘Apple’ mango fruit with and without russeting (b). Permeance of water vapour diffusion through the ES (b inset) was calculated under conditions of steady state water loss. Data represent means ± SE of a minimum of 10 replicates. Full article ">Figure 7
Photograph of ‘Apple’ mango and sketch illustrating the nomenclature used to describe regions of the fruit surface [<a href="#B41-plants-09-00898" class="html-bibr">41</a>]. Full article ">

14 pages, 910 KiB

Open AccessArticle

Biochemical Analysis of Organic Acids and Soluble Sugars in Wild and Cultivated Pomegranate Germplasm Based in Pakistan

by Muhammad Nafees, Muhammad Jafar Jaskani, Ishtiaq Ahmad, Maryam, Irfan Ashraf, Ambreen Maqsood, Sunny Ahmar, Muhammad Azam, Sajjad Hussain, Asma Hanif and Jen-Tsung Chen

Plants 2020, 9(4), 493; https://doi.org/10.3390/plants9040493 - 11 Apr 2020

Cited by 14 | Viewed by 4464

Abstract

Pomegranate is famous for its health benefiting chemical and biochemical constituent compounds. The present study was undertaken to characterize pomegranate germplasm for its various fruit traits, acids, and sugar profiling through high performance liquid chromatography (HPLC) analysis. Among 11 detected acids and 8 [...] Read more.

Pomegranate is famous for its health benefiting chemical and biochemical constituent compounds. The present study was undertaken to characterize pomegranate germplasm for its various fruit traits, acids, and sugar profiling through high performance liquid chromatography (HPLC) analysis. Among 11 detected acids and 8 sugars, citric acid and fructose were predominant in 18 domestic and 5 wild genotypes, respectively. Fruit weight, aril weight and wood portion index (WPI) were ranged from 15.82% to 24.42%, 10.99% to 113.78%, and 2.39% to 17.25%, respectively. Genotypes were grouped as sweet, sweet–sour, sour–sweet, and sour based on citric acid contents. Lactic acid and pyruvic acid showed the highest correlation (r = 0.92), however, sour and sweet genotypes had strong association for acids and sugars, respectively. Straddling of dendrogram showed the flow of genetic material in a cultivated location with wild and cultivated pomegranates grouped in different classes, however, wild and sour landraces grouped in the same class with 71% similarity of traits. Based on the observations of the current study, it was concluded that selected wild and arid zones (Multan, Bahawalpur) genotypes are poor in nutrients (acid and sugars) quality, however, genotypes of Rahim-Yar-Khan, Muzafar Garh, and Khyber Pakhtunkhwa have a better composition of sugars and acids. Full article

(This article belongs to the Special Issue Physiological Responses of Tree Fruits to Environmental and Management Factors)

► Show Figures

Figure 1

15 pages, 3057 KiB

Open AccessArticle

Water Deficit Affects the Growth and Leaf Metabolite Composition of Young Loquat Plants

by Giovanni Gugliuzza, Giuseppe Talluto, Federico Martinelli, Vittorio Farina and Riccardo Lo Bianco

Plants 2020, 9(2), 274; https://doi.org/10.3390/plants9020274 - 19 Feb 2020

Cited by 18 | Viewed by 4416

Abstract

Water scarcity in the Mediterranean area is very common and understanding responses to drought is important for loquat management and production. The objective of this study was to evaluate the effect of drought on the growth and metabolism of loquat. Ninety two-year-old plants [...] Read more.

Water scarcity in the Mediterranean area is very common and understanding responses to drought is important for loquat management and production. The objective of this study was to evaluate the effect of drought on the growth and metabolism of loquat. Ninety two-year-old plants of ‘Marchetto’ loquat grafted on quince were grown in the greenhouse in 12-liter pots and three irrigation regimes were imposed starting on 11 May and lasting until 27 July, 2013. One-third of the plants was irrigated with 100% of the water consumed (well watered, WW), a second group of plants was irrigated with 66% of the water supplied to the WW plants (mild drought, MD), and a third group was irrigated with 33% of the water supplied to the WW plants (severe drought, SD). Minimum water potential levels of −2.0 MPa were recorded in SD plants at the end of May. Photosynthetic rates were reduced according to water supply (WW > MD > SD), especially during the morning hours. By the end of the trial, severe drought reduced all growth parameters and particularly leaf growth. Drought induced early accumulation of sorbitol in leaves, whereas other carbohydrates were not affected. Of over 100 leaf metabolites investigated, 9 (squalene, pelargonic acid, glucose-1-phosphate, palatinol, capric acid, aconitic acid, xylitol, lauric acid, and alanine) were found to be useful to discriminate between the three irrigation groups, suggesting their involvement in loquat metabolism under drought conditions. Loquat behaved as a moderately drought-tolerant species (limited stem water potential and growth reductions) and the accumulation of sorbitol in favor of sucrose in mildly-stressed plants may be considered an early protective mechanism against leaf dehydration and a potential biochemical marker for precise irrigation management. Full article

(This article belongs to the Special Issue Physiological Responses of Tree Fruits to Environmental and Management Factors)

► Show Figures

Figure 1

Figure 1
Stem water potential in loquat plants under well-watered conditions (WW), mild-drought (MD), and severe drought (SD) during the four months of the trial. Error bars represent standard errors of means. When present, different letters indicate significant differences among drought treatments for a specific date (Tukey’s multiple range test, p < 0.05). Full article ">Figure 2
Daily trends of photosynthetic rate (PS) and stomatal conductance (gs) in loquat plants under well-watered conditions (WW), mild drought (MD) and severe drought (SD) on 29 May ((A) and (C)) and 26 July ((B) and (D)). Error bars represent standard errors of means. Significance level from analysis of variance: n.s., non-significant; **, significant at P < 0.001. When present, different letters indicate significant differences among irrigation treatments for a specific date (Tukey’s multiple range test, p < 0.05). Full article ">Figure 3
Photosynthetic rates (PS) (A) and stomatal conductance (gs,) (B) in loquat plants under well-watered conditions (WW), mild drought (MD) and severe drought (SD) during the four months of drought. Significance level from analysis of variance: n.s., non-significant; **, significant at p < 0.001. Error bars represent standard errors of means. Full article ">Figure 4
(A) Sorbitol, (B) sucrose, (C) glucose, and (D) fructose content in leaves of loquat plants under well-watered conditions (WW), mild drought (MD), and severe drought (SD) during the four months of drought. Error bars represent standard errors of means. When present, different letters indicate significant differences among drought treatments for a specific date (Tukey’s multiple range test, p < 0.05). Full article ">Figure 5
Canonical score plot from linear discriminant analysis of metabolites detected in leaves of loquat plants under well-watered conditions (WW), mild drought (MD) and severe drought (SD) during the four months of trial. Full article ">

Journal Menu

Journal Browser

Physiological Responses of Tree Fruits to Environmental and Management Factors

Share This Special Issue

Special Issue Editor

Special Issue Information

Keywords

Benefits of Publishing in a Special Issue

Published Papers (14 papers)

Research

Further Information

Guidelines

MDPI Initiatives

Follow MDPI