Agromorphological and Chemical Characterization of Pear Cultivars Grown in Central–West Iberian Peninsula
Faculty of Agricultural and Environmental Sciences, University of Salamanca, Avda. Filiberto Villalobos, 119, 37007 Salamanca, Spain
*
Author to whom correspondence should be addressed.
Agronomy 2023, 13(12), 2993; https://doi.org/10.3390/agronomy13122993
Submission received: 9 November 2023
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Revised: 1 December 2023
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Accepted: 4 December 2023
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Published: 5 December 2023
(This article belongs to the Section Horticultural and Floricultural Crops)
Abstract
:Seventeen traditional pear cultivars grown in the Central–Western Iberian Peninsula, all of them clearly in decline or close to extinction, have been characterized from the point of view of agromorphological and chemical. A total of twenty-one agromorphological and chemical traits, mainly defined by the International Union for the Protection of New Varieties of Plants, were used to describe the fruits during a 3-year period from 2020 to 2022. Some of the genotypes showed distinctive and interesting agronomical characteristics from a commercial point of view, such as high yields and fruit quality. This was the case of the pear cultivars called “Pera Temprana”, “Muslo de Dama”, and “Pera de Cristal de Peñacaballera”. Their fruits were quite heavy (125.32–142.56 g) and had a good sweetness/acidity balance (12.67–14.92° Brix/2.76–3.42 g malic acid/L). The rest of the pear cultivars, with the exception of the “Cermeños” group and “Pera Canela” genotype, also presented interesting commercial characteristics given that their fruits had equatorial diameters greater than 6 cm and total soluble solids levels close to or above 13° Brix. The results of the PCA and cluster analysis showed that agromorphological and chemical analysis can provide reliable information on the variability in pear cultivars. The loss of these traditional crops has enormous significance given that they have unique characteristics and are perfectly adapted to the edapho-climatic conditions of the region. This work constitutes an important step in the conservation of genetic pear resources in the Central–Western Iberian Peninsula.
1. Introduction
The pear (Pyrus communis (L.), Rosaceae, mainly 2n = 2x = 34 [1,2,3,4]) is one of the oldest and most important fruit crops grown commercially worldwide. It originated in the Caucasus region (Southeastern Europe between the Black and Caspian seas) from where it spread to the rest of Europe and Asia through Indo–European tribes [5]. Their fruits are commonly consumed fresh, canned, as juice, and dried. They are also used to produce “perry”, an alcoholic beverage [6]. By 2021, the world production of pear was 25.65 million metric tons [7]. China, the United States, Argentina, Turkey, and South Africa are the most important pear-producing countries (approximately 84% of world pear production). The world trade is based on a few varieties [8,9]; “Conference“, “Abate Fetel“, and “Williams“ represent more than 65% of the European pear production [10]. Concretely, the Iberian Peninsula (the first European Producer) has 31,180 ha dedicated to pear production and produces 541,630 metric tons of fruit per year. The main pear-producing regions in the Iberian Peninsula are the Ebro Valley (Catalonia, Aragon), Jumilla (Murcia), Extremadura, and ‘Ribatejo e Oeste’. Some of the most common cultivars cultured in the Iberian Peninsula are “Conference“, “Blanquilla“, “Limonera“, “Ercolini“, “Williams“, and “Rocha”. In these areas, the cultivation is mainly carried out in small orchards, in dry conditions, and with ecological management. Moreover, it is also important to point out that many local traditional cultivars have been abandoned and replaced by modern cultivars (very close genetically) bred to meet the demands of both producers and consumers. The loss of these traditional crops has enormous significance given that they have unique characteristics and are perfectly adapted to the edapho-climatic conditions of the region. Some of these genotypes show distinctive agronomic characteristics such as frost tolerance, late-blooming, and self-compatibility. The conservation and characterization of these local cultivars are important to avoid the loss of genetic variability and as a potential source of genetic variation for future pear breeding programs.
Many studies addressing the agromorphological and biochemical characterization of pear cultivars have been undertaken in countries around the world [11,12,13,14,15,16,17,18,19,20], among others. In this sense, some works addressing to agromorphological characterization of pear cultivars have been reported in the Iberian Peninsula during the last years: Herrero-Catalina [21], Voltas, et al. [22], Calouro et al. [23], Iglesias [24], Pereira-Lorenzo et al. [25], Pedro et al. [26], Espiau and Alonso-Segura [27], and Fadon et al. [28]. These works have focused on the northern peninsular and the western Portuguese regions. However, there have been no agromorphological studies of pear cultivars in the Central–West Iberian Peninsula.
The objective of the present study is to survey, identify, and characterize the traditional pear cultivars existing in the Central–West Region of the Iberian Peninsula. Therefore, an exhaustive survey will be carried out in the main pear-producing areas and the traditional cultivars located will be agromorphologically and chemically characterized through the employ of 21 fruit descriptors. The statistical analysis of the recorded information, using a principal component analysis (PCA) and a dendrogram, will allow the identification clearly the cultivars, detect the possible existence of homonymies o sinonymies, and select the most significant descriptors. These works will contribute very significantly to avoiding the disappearance of these unique traditional pear cultivars which will also be included in future pear breeding programs.
2. Materials and Methods
2.1. Plant Material
A survey was carried out in the regions known as “Arribes del Duero” and “Sierra de Francia” (Salamanca, Spain), “Toro” (Zamora, Spain), and “Valle del Tiétar” (Ávila, Spain) in 2019. The edaphoclimatic conditions in these regions are mostly associated with microclimatic areas (Table 1) and had mainly acidic soils from the decomposition of granitic rocks.
During this phase of the research, 43 interviews were conducted with farmers and cooperatives that operate in different areas. The process consisted of locating, by GPS, and labeling pear tree cultivars with specific names that farmers indicated were old or local. For each marked tree, an information file was recorded that included data on the place of collection. A total of 153 adult pear trees at least ten years old and corresponding to 17 cultivars were selected for study at full fruit maturity. A list of these cultivars and their place of collection is shown in Table 2. The “Limonera” and “Blanquilla de Aranjuez” cultivars were considered as references. Nine trees were evaluated per cultivar.
2.2. Agromorphological Characterization
The agromorphological description of the pear cultivars was based on 15 descriptors established by the International Convention for the Protection of New Varieties of Plants (UPOV) [29] a further 6 descriptors that were considered relevant for identification (Table 3). For the determination of the descriptors, samples of fruits were taken during 2020, 2021, and 2022, using UPOV guidelines. Pear fruit was collected at maturity. The time of maturity was reached based on the color and firmness characteristics of each cultivar, taking into account information provided by growers and from personal experience and observation. A total of 10 fruits per tree and year were randomly taken from the middle of the tree top to determine each parameter.
Concerning quantitative parameters, the two principal dimensions of fruits, length and maximum diameter, were measured using a digital caliper with a sensibility of 0.01 mm. The following ratios were also calculated: fruit length/maximum diameter and stalk length/thickness. The caliper was also used to measure the rest of the fruit parameters: stalk length and thickness, eye basin depth, and width and depth of the stalk cavity. The volume and surface area were calculated according to Babic et al. [30]. The mass was measured on an electronic balance with a sensitivity of ± 0.001 g. The time of maturity for consumption was also determined based on the color characteristics of each cultivar, taking into account information provided by growers and from personal experience and observation. Moreover, the following qualitative descriptors were observed: position of maximum diameter, the profile of fruit sides, ground color of fruit skin, relative area of over color, and the presence or absence of russeting on the fruit skin.
2.3. Chemical Composition
Seven ripe pears were also randomly selected from the middle of the tree top per tree and year and their skin was removed to obtain the pulp. Then they were finely milled by an electric grinder and filtered to obtain the juice. Then it was analyzed, with three replicates, for the following parameters: total soluble solids, pH, and titratable acidity. Total soluble solids in each fruit were determined with a digital refractometer (Atago PR-101, Atago Co. Ltd., Tokyo, Japan) at 20 °C. The pH was measured using the HQ40d portable meters (HACH Corp., Loveland, CO, USA). Finally, the titratable acidity was determined in each fruit by potentiometric titration with 0.1 N NaOH up to pH 8.1, using 1 mL of diluted juice in 25 mL distilled H2O.
2.4. Statistical Analyses
Means and standard deviations were calculated, for each of the quantitative parameters studied, over the 3 years for the 17 traditional pear genotypes. The unit of measurement of each of the descriptors studied was based on the individual value of each of the eight trees sampled per genotype. Finally, based on all the studied traits, a principal component analysis (PCA) was also carried out using the SPSS 17.0 program, and a dendrogram of genetic similarities among genotypes was compiled using the furthest neighbor method (Statgraphics Plus 17.0 program).
3. Results and Discussion
3.1. Agromorphological Characterization
Quantitative fruit parameters are shown in Table 4 and Table 5. Stalk length ranged from 1.53 to 4.24 cm, being “Pera de Manteca”, “Pera de San Juan”, and “De Invierno” the cultivars with the longest stalks. However, it can be observed that there was no relation between the length and thickness stalk (correlation coefficient = 0.20). Similar results for these parameters were also recorded for local pear genotypes cultivated in North–Eastern Spain by Voltas et al. [22]: Stalk length = 2.5 cm and stalk thickness = 0.3 cm. However, it is also important to point out that Herrero-Catalina [21] generally found shorter fruit stalks in the named “Mantecosa” cultivars. Moreover, it is also important to point up that the “Pera de Cristal de Toro” and “Pera de Cristal de Peñacaballera” genotypes recorded significant differences for the stalk length parameter (1.58 and 2.22 cm, respectively). In this sense, Herrero-Catalina [21] also observed important variability for the stalk length in the “Don Guindo” genotype. Regarding fruit length, it varied from 5.35 to 11.07 cm. The lowest values were observed for “Cermeño Verde”, “Cermeño Común”, and “Pera Canela”. These last three cultivars also showed the lowest fruit diameters (4.61–5.15 cm). In general, lower fruit size parameters were recorded by Voltas et al. [22] and Pereira-Lorenzo et al. [25]. It can be said that the local growers have improved these traditional pear cultivars from the Central–West Iberian Peninsula for a long time. Thus, in general, it can be observed that practically all the pear cultivars studied present acceptable productive characteristics for the market. Its fruits have an equatorial caliber greater than 6 cm. Moreover, it is also important to point out that consumers also look for pears with acceptable hardness (around 6 kg/cm2) and good conservation. In this sense, the values of the length/maximum diameter ratio were similar to those recorded by Voltas et al. [22] and Pereira-Lorenzo et al. [25] (around 1.2). Concerning fruit volume, surface area, and weight, “Muslo de Dama”, “Pera Temprana”, and “Limonera” were the cultivars with the largest and heaviest fruits (close to 39.68 cm3, 86.52 cm2, and 138.37 g). On the other hand, were the cultivars commonly called “Cermeño” with 20.48 cm3, 44.66 cm2 and 70.35 g. In this sense, Han et al. [31] observed that the high temperatures during the fruit growing season are related positively to bigger fruit diameter and negatively to fruit size. In this sense, it is also important to point up that again the “Pera de Cristal de Toro” and “Pera de Cristal de Peñacaballera” cultivars recorded significant differences for the weight and size parameters (104.92 g, 66.20 cm2, 30.37 mm3; 125.32 g, 78.92 cm2, 36.20 mm3, respectively). With respect to it, Herrero-Catalina [21] also observed large fruits for the “Pera de Roma” and “Limonera” genotypes and small fruits for the named “Cermeño” group cultivars. In general, cultivars with larger and heavier fruits are considered by farmers to have the highest yields per tree. Moreover, it can be observed, that all the pear cultivars had some stalk cavity, being “De invierno”, “Cermeño Común”, “Pera Temprana”, “Blanquilla de Aranjuez”, and “Pera de Agua” the genotypes that showed the greatest depth of stalk cavity (4.23–4.61 mm). Voltas et al. [22] also observed an important number of pear cultivars with medium or shallow peduncle cavities. On the contrary, “Pera Canela” didn’t show a stalk cavity. Concerning the eye basin, “Pera de Manteca” and “Pera de San Juan” were the genotypes that showed the more pronounced cavity (around depth = 10.10 mm and width = 3.11 cm). In this sense, Herrero-Catalina [21] also observed important eye basin cavities in pears of the “Donguindo” genotype. Moreover, it is also important to point out that the “Cermeño Verde” and “Cermeño Común” cultivars recorded significant differences at the level of the eye basin parameters (depth: 1.46 and 3.22 mm; width: 1.17 and 2.02 cm, respectively). Finally, in relation to the time of maturity for consumption, “Pera de San Juan” was the genotype with the earliest fruits, followed by the “Cermeños” group cultivars (June and July/August, respectively). On the other hand, was the “Pera de Invierno” cultivar (October–November). The rest of the pear cultivars ripen their fruits in September. Herrero-Catalina [21] also observed that the “Sanjuaneño” genotype had early crops (end of June or beginning of July).
Qualitative fruit parameters are summarized in Table 6. Regarding the position of maximum fruit diameter, “Bella Angelina”, “Muslo de Dama”, and “Pera de Cristal de Toro” were the unique genotypes that showed wide fruits on the part closest to the calyx. It is also important to point out that the “Pera de Cristal de Peñacaballera” had fruits with the maximum diameter in the middle. Moreover, all the pear cultivars, except “Bella Angelina” and “Muslo de Dama”, showed convex or straight profiles of fruit sides. Similar results for this descriptor were also recorded for local Spanish pear cultivars by Voltás et al. [22]. Concerning the ground color of fruit skin, there was an important variation from green to yellow. The cultivars with the green ground color of fruit skin were “De Invierno”, “Muslo de Dama”, “Pera de Cristal de Toro”, “Pera de Cristal de Peñacaballera”, “Pera de Roma”, and “Pera de San Juan”. On the other hand, were “Pera Canela”, “Pera del País”, and “Pera Temprana” (yellow fruit skin). The relative area of overcolour ranged from absent or very small to medium. The cultivars commonly named “Pera de Cristal” also showed differences for this parameter. The relative area of overcolor was medium in “Pera de Cristal de Toro” and small in “Pera de Cristal de Peñacaballera”. Finally, this last cultivar was the unique genotype that showed russet on fruit skin. In this sense, Winkler et al. [32] indicated that extended periods of exposure of fruit surfaces to moisture, either as liquid water or as high water–vapor concentration (high relative humidity) have been identified as causal in russeting. Asin [33] also observed that natural russeting in pears is directly related to low temperatures and high humidity in the weeks following bloom. Espiau and Alonso-Segura [27] also supposed that the fact that average Spanish climatic conditions show higher temperatures and lower humidity than average European conditions, could have affected a selection pressure on the local accessions.
3.2. Chemical Composition
Concerning the chemical parameters, total soluble solids showed low variation in all cases, ranging from 12 to 14 °Brix. Similar values were recorded by Calouro et al. [23], Pereira-Lorenzo et al. [25], and Pedro et al. [26]. However, Espiau and Alonso-Segura [27] registered higher values in the Spanish Pear Germplasm Bank in Zaragoza (12–19 °Brix). It could be because many selected genotypes for this parameter are included in it. Thus, in general, it can be observed that practically all the pear cultivars studied present acceptable productive characteristics for the market. Its fruits presented values of total soluble solids higher than 13 °Brix. pH varied from 3.76 to 4.47, being “Cermeño Verde” and “Muslo de Dama” the cultivars with the lowest and highest values, respectively. Similar results for this parameter were recorded by Pereira-Lorenzo et al. [25] (between 3.66 and 4.71). With respect to titratable acidity, “Muslo de Dama” also recorded the highest values (3.42 g malic acid/L). On the other hand, were “Limonera” and “Pera de Cristal de Peñacaballera” (2.76 g/L). Greater variations for this parameter were found by Pereira-Lorenzo et al. [25] (1.52–4.09 g/L). In this sense, Pedro et al. [26] registered very high values for titratable acidity in “Pera Rocha do Oeste” fruits (4.81). Considering this value, the fruits of this last cultivar can be classified as acidic.
Regarding the total soluble solids/titratable acidity ratio, the pear genotypes had fruits that were very balanced between sweetness and acidity (3.77–5.09). This ratio is very important and determines the quality commercial of the production. The taste and flavor of any fresh fruit is an interaction between total soluble solids and acidity which depends highly on its maturity stage [34]. Similar values for this ratio (4.21) were recorded by Pereira-Lorenzo et al. [25] with local pears from North–Western Spain.
3.3. Statistical Analyses
A principal component analysis (PCA) was used to identify the traits with the highest variation among cultivars and the greatest impact on the separation of them in the data set [35]. The PCA results based on fruit descriptors showed that more than 58% of the variability observed was explained by the first three components (PC1–PC3). These results agree with those obtained by Bashiri et al. [36], Khadivi et al. [37], Zheng et al. [38], and Ying et al. [39] for pear cultivars; the PCA revealed that the first 3 components explained comparable values (from 28.07% to 81.33%) of the total variation, based on morphological and biochemical traits. The first component (PC1), accounting for 31.10% of the total variance, was influenced by pear weight and size parameters such as length, maximum diameter, volume, and surface area. The second component (PC2) accounted for 17.32% of the total variation and was mainly explained by fruit petiole length, depth of stalk cavity, eye basin depth and width, and position of maximum diameter. Finally, the third principal component (PC3), explaining 10.48% of the total variation, was integrated by the stalk thickness and the ratio length/thickness of the stalk. In this sense, Rotach and Baume [40], Voltás et al. [22], and Heidari et al. [41] also observed that fruit traits are very useful tree characteristics for identification purposes. Leaf-related traits alone are insufficient for morphological classifications of Pyrus (Voltás et al. [22]). Moreover, these authors applied and recommended multivariate techniques for analysis of the leaf, shoot, and fruit morphometric data of pear genotypes. Figure 1 shows a scatterplot of the first two principal components (PCs) for the 17 traditional pear genotypes based on agromorphological and chemical characters. It can be observed that there is high variation among cultivars, indicating that the studied germplasm is a good candidate gene pool for breeding programs.
Figure 2 shows a dendrogram of the relationships among the pear genotypes from the analysis of all the agromorphological and chemical traits studied. It can be observed that “Pera de Cristal de Peñacaballera”, “Muslo de Dama”, “Pera Temprana”, and “Limonera” cultivars showed the greatest differences with respect to the rest of the cultivars included in the study. Its fruits showed a large size in comparison with the rest. By analyzing the dendrogram, a series of synonyms among the pear cultivars can also be detected. Such is the case with “Blanquilla de Aranjuez” and “Pera de Agua”, and “Pera de Roma” and “De Invierno”. Significant similarities were observed between the cultivars for these two cases of synonymies for all agromorphological and chemical traits. By contrast, a homonymy was also detected: “Pera de Cristal de Toro” and “Pera de Cristal de Peñacaballera”. Despite their major agromorphological and chemical differences, both names are often used interchangeably by some growers.
The results of the PCA and cluster analysis showed that agromorphological and chemical analysis can provide reliable information on the variability in pear cultivars. In correspondence with our findings, Bashiri et al. [36], Khadivi et al. [37], Zheng et al. [38], Ying et al. [39], and Somayeh et al. [42] showed also that morphological evaluation is an efficient tool for characterization of pear germplasm and species distinction. The overall analysis of all descriptors illustrates a wide diversity that may have important implications for the management of genetic resources.
4. Conclusions
Seventeen traditional pear cultivars are grown in the Central–Western Iberian Peninsula, all of them clearly in decline or close to extinction and have been characterized from the point of view of agromorphological and chemical. Some of the genotypes showed distinctive and interesting agronomical characteristics from a commercial point of view, such as high yields and fruit quality. This was the case of the pear cultivars called “Pera Temprana”, “Muslo de Dama”, and “Pera de Cristal de Peñacaballera”. Their fruits were quite heavy (125.32–142.56 g) and had a good sweetness/acidity balance (12.67–14.92° Brix/2.76–3.42 g malic acid/L). The rest of the pear genotypes, with the exception of the “Cermeños” group and “Pera Canela” genotype, also presented interesting commercial characteristics given that their fruits had equatorial diameters greater than 6 cm and total soluble solids levels close to or above 13° Brix. The results of the PCA and cluster analysis showed that agromorphological and chemical analysis can provide reliable information on the variability in pear genotypes. Two synonymies (“Blanquilla de Aranjuez” and “Pera de Agua”; “Pera de Roma” and “De Invierno”) and one homonymy (“Pera de Cristal de Toro” and “Pera de Cristal de Peñacaballera”) were also detected. This work constitutes an important step in the conservation of genetic pear resources in the Central–Western Iberian Peninsula.
Author Contributions
Conceptualization, R.P.-S. and M.R.M.-C.; Methodology, R.P.-S. and M.R.M.-C.; Software, R.P.-S.; Validation, R.P.-S. and M.R.M.-C.; Investigation, R.P.-S. and M.R.M.-C.; Data curation, R.P.-S. and M.R.M.-C.; Writing—original draft preparation, R.P.-S.; Writing—review and editing, R.P.-S. and M.R.M.-C.; Project administration, R.P.-S.; Funding acquisition, R.P.-S. All authors have read and agreed to the published version of the manuscript.
Funding
This research was supported by the Biodiversity Foundation of the Spanish Ministry of Environment and Rural and Marine Affairs (MARM) and the Spanish Federation of Municipalities and Provinces (FEMP). (Project reference: MARM-FB-2008-012).
Data Availability Statement
All data generated or analyzed during this study are included in this published article.
Acknowledgments
The authors thank the pear growers of the “Arribes del Duero” and “Sierra de Francia” (Salamanca), “Toro” (Zamora), and “Valle del Tiétar” (Ávila) for their major contribution to this work.
Conflicts of Interest
The authors declare no conflict of interest.
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Figure 1.
Scatter plot of the first two principal components (PCs) for the 17 traditional pear genotypes based on agromorphological and chemical descriptors.
Figure 1.
Scatter plot of the first two principal components (PCs) for the 17 traditional pear genotypes based on agromorphological and chemical descriptors.
Figure 2.
Dendrogram produced using the furthest neighbor method (Euclidean) from the agromorphological and chemical characteristics of traditional pear cultivars included in the study.
Figure 2.
Dendrogram produced using the furthest neighbor method (Euclidean) from the agromorphological and chemical characteristics of traditional pear cultivars included in the study.
Table 1.
Meteorological conditions for the studied regions in the Central–West Iberian Peninsula.
| Regions | Average Altitude above Sea Level (m) | Average Temperature (°C) | Total Rainfall (mm) | Total Sunshine Radiation (GJ/m2) |
|---|---|---|---|---|
| Arribes del Duero | 680 | 13.1 | 747 | 6.05 |
| Sierra de Francia | 782 | 13.4 | 980 | 6.10 |
| Toro | 992 | 12.1 | 426 | 6.17 |
| Valle del Tiétar | 721 | 14.7 | 1020 | 6.14 |
Data provided by the Spanish National Meteorological Agency (AEMET).
Table 2.
List of pear cultivars examined in this study.
| Sampling Location | |||
|---|---|---|---|
| Arribes del Duero | Sierra de Francia | Toro | Valle del Tiétar |
| “Blanquilla de Aranjuez” “Pera Canela” “Pera Roma” “Pera del País” | “Bella Angelina” “Muslo de Dama” “Pera Cristal Peñacaballera” “Limonera” “Blanquilla de Aranjuez” | “Cermeño Común” “Cermeño Verde” “Pera Cristal Toro” “Limonera” “Blanquilla de Aranjuez” | “De Invierno” “Don Guindo” “Limonera” “Pera de Agua” “Pera Manteca” “Pera de San Juan” “Pera Temprana” “Blanquilla de Aranjuez” |
Table 3.
List of the descriptors selected for the characterization of pear cultivars.
| Quantitative Descriptors | |
| Length of stalk (cm) | cm |
| Thickness of stalk | cm |
| Ratio length/thickness of stalk | |
| Fruit length | cm |
| Maximum diameter of fruit | cm |
| Length/maximum diameter ratio | |
| Fruit volume | mm3 |
| Fruit surface area | cm2 |
| Weight | g |
| Time of maturity for consumption | |
| Depth of stalk cavity | mm |
| Depth of eye basin | mm |
| Width of eye basin | cm |
| Total soluble solids | °Brix |
| pH | |
| Titratable acidity | g malic acid/L |
| Qualitative descriptors | |
| Position of maximum fruit diameter | In the middle-Clearly towards calyx |
| Profile of fruit sides | Concave-Convex |
| Ground color of fruit skin | Green-Yellow |
| Relative area of overcolor | Absent or very small-Very large |
| Russet on the fruit skin | Yes-No |
Table 4.
Means, standard deviations, and ANOVA analyses for some quantitative fruit parameters in pear cultivars of the Central–West Iberian Peninsula.
Table 4.
Means, standard deviations, and ANOVA analyses for some quantitative fruit parameters in pear cultivars of the Central–West Iberian Peninsula.
| Cultivar | Length of Stalk (cm) | Thickness of Stalk (cm) | Ratio Length/ Thickness of Stalk | Fruit Length (cm) | Maximum Diameter of Fruit (cm) | Length/Maximum Diameter Ratio | Fruit Volume (mm3) | Fruit Surface Area (cm2) |
|---|---|---|---|---|---|---|---|---|
| Bella Angelina | 2.14 (0.26) b | 0.40 (0.03) i | 5.35 ± 0.12 a | 6.65 (0.46) c | 5.83 (0.29) d | 1.14 (0.02) abcde | 24.69 (2.31) bc | 53.83 (0.33) c |
| Cermeño Común | 3.51 (0.32) g | 0.34 (0.02) gh | 10.32 ± 0.22 h | 5.67 (0.39) b | 4.79 (0.34) b | 1.18 (0.03) de | 21.07 (1.64) ab | 45.94 (0.34) b |
| Cermeño Verde | 3.38 (0.23) fg | 0.20 (0.02) ab | 16.90 ± 0.27 m | 5.35 (0.31) a | 4.61 (0.37) a | 1.16 (0.04) cde | 19.90 (1.93) a | 43.38 (0.29) a |
| De Invierno | 3.65 (0.28) g | 0.28 (0.02) ef | 13.03 ± 0.17 k | 9.47 (0.54) i | 8.23 (0.27) l | 1.15 (0.03) bcde | 35.17 (2.98) ghi | 76.68 (0.30) i |
| Don Guindo | 2.95 (0.29) ef | 0.31 (0.02) fg | 9.51 ± 0.18 f | 8.60 (0.43) g | 7.27 (0.31) i | 1.18 (0.02) de | 31.97 (1.83) efg | 69.69 (0.35) g |
| Limonera | 1.53 (0.33) a | 0.21 (0.02) abc | 7.28 ± 0.14 d | 10.37 (0.59) k | 9.08 (0.35) n | 1.14 (0.04) abcde | 38.51 (3.00) ijk | 83.96 (0.41) k |
| Muslo de Dama | 2.66 (0.28) cde | 0.27 (0.02) de | 9.85 ± 0.13 g | 11.07 (0.62) m | 9.72 (0.28) p | 1.13 (0.02) abcd | 41.13 (3.05) k | 89.67 (0.39) m |
| Pera de Agua | 2.25 (0.27) bcd | 0.34 (0.02) gh | 6.61 ± 0.10 b | 7.37 (0.48) d | 6.48 (0.36) g | 1.13 (0.02) abcd | 27.38 (2.48) cd | 59.69 (0.36) d |
| Blanquilla de Aranjuez | 2.26 (0.31) bcd | 0.35 (0.03) h | 6.45 ± 0.11 b | 7.54 (0.37) e | 6.43 (0.39) fg | 1.17 (0.04) cde | 28.02 (1.46) cde | 61.08 (0.39) e |
| Pera Canela | 2.45 (0.27) bcd | 0.31 (0.02) fg | 7.90 ± 0.13 e | 5.65 (0.32) b | 5.15 (0.28) c | 1.09 (0.03) a | 28.30 (2.03) cde | 45.81 (0.29) b |
| Pera Cristal Toro | 1.58 (0.30) a | 0.22 (0.02) bc | 7.18 ± 0.10 cd | 8.17 (0.40) f | 7.38 (0.34) j | 1.10 (0.02) ab | 30.37 (2.86) def | 66.20 (0.41) f |
| Pera Cristal Peñacaball. | 2.22 (0.34) bc | 0.32 (0.02) gh | 6.93 ± 0.12 c | 9.74 (0.53) j | 8.36 (0.27) m | 1.16 (0.04) cde | 36.20 (3.02) hij | 78.92 (0.42) j |
| Pera de Manteca | 4.24 (0.20) h | 0.34 (0.03) gh | 12.47 ± 0.19 j | 7.47 (0.46) e | 6.28 (0.38) e | 1.19 (0.04) e | 27.77 (1.20) cd | 60.53 (0.32) e |
| Pera de Roma | 2.54 (0.34) bcde | 0.33 (0.02) gh | 7.69 ± 0.11 e | 9.02 (0.51) h | 7.93 (0.41) k | 1.13 (0.03) abcd | 33.53 (1.73) fgh | 73.09 (0.44) h |
| Pera de San Juan | 4.24 (0.33) h | 0.34 (0.03) gh | 12.47 ± 0.12 j | 7.37 (0.44) d | 6.58 (0.39) h | 1.12 (0.02) abc | 27.39 (2.05) cd | 59.71 (0.29) d |
| Pera del País | 2.75 (0.29) de | 0.24 (0.01) cd | 11.45 ± 0.10 i | 7.47 (0.49) e | 6.40 (0.30) f | 1.16 (0.04) cde | 27.76 (2.53) cd | 60.52 (0.34) e |
| Pera Temprana | 2.66 (0.32) cde | 0.18 (0.01) a | 14.77 ± 0.15 l | 10.61 (0.53) l | 9.32 (0.37) o | 1.13 (0.03) abcd | 39.42 (3.34) jk | 85.93 (0.43) l |
ANOVA, analysis of variance; a–p Different letters in the same column indicate significant differences LSD (p < 0.05).
Table 5.
Means, standard deviations, and ANOVA analyses for some quantitative fruits parameters in pear cultivars of Central–West Iberian Peninsula (Continuation).
Table 5.
Means, standard deviations, and ANOVA analyses for some quantitative fruits parameters in pear cultivars of Central–West Iberian Peninsula (Continuation).
| Cultivar | Weight (g) | Time of Maturity for Consumption | Depth of Stalk Cavity (mm) | Depth of Eye Basin (mm) | Width of Eye Basin (cm) | Total Soluble Solids (° Brix) | pH | Titratable Acidity (g Malic Acid/L) |
|---|---|---|---|---|---|---|---|---|
| Bella Angelina | 86.37 (4.42) b | September | 2.14 (0.26) e | 3.14 (0.29) b | 1.97 (0.12) cd | 13.82 (0.83) cde | 4.16 (0.27) abc | 2.92 (0.12) ab |
| Cermeño Común | 72.40 (4.15) a | July-August | 4.59 (0.25) i | 3.22 (0.25) b | 2.02 (0.18) cd | 13.04 (0.42) abcd | 4.04 (0.33) abc | 3.10 (0.24) abcde |
| Cermeño Verde | 68.30 (4.63) a | July-August | 1.73 (0.21) d | 1.46 (0.13) a | 1.17 (0.20) a | 14.29 (0.67) e | 3.76 (0.21) a | 2.87 (0.19) ab |
| De Invierno | 120.43 (8.70) f | October-November | 4.61 (0.27) i | 5.41 (0.40) d | 2.32 (0.11) e | 12.87 (0.58) ab | 4.28 (0.18) bc | 2.99 (0.31) abcde |
| Don Guindo | 109.21 (6.31) de | September | 3.67 (0.24) h | 4.63 (0.31) c | 2.63 (0.12) f | 13.11 (0.34) abcd | 3.97 (0.36) ab | 3.30 (0.28) bcde |
| Limonera | 136.00 (8.82) g | September | 2.06 (0.14) de | 5.34 (0.42) d | 2.06 (0.11) cd | 14.07 (0.39) e | 4.39 (0.28) bc | 2.76 (0.34) a |
| Muslo de Dama | 142.56 (10.12) g | September | 1.23 (0.12) c | 3.68 (0.28) b | 1.88 (0.09) bc | 14.92 (0.51) ab | 4.47 (0.17) c | 3.42 (0.26) e |
| Pera de Agua | 94.48 (6.30) bc | September | 4.23 (0.31) i | 8.62 (0.53) f | 2.16 (0.13) de | 13.83 (0.73) de | 4.31 (0.22) bc | 3.10 (0.32) abcde |
| Blanquilla de Aranjuez | 96.71 (4.94) bc | September | 4.34 (0.28) i | 8.77 (0.49) f | 2.18 (0.17) de | 13.00 (0.34) abcd | 4.28 (0.25) bc | 2.85 (0.20) ab |
| Pera Canela | 74.80 (4.82) a | September | 0.00 (0.00) a | 3.52 (0.28) b | 2.06 (0.17) cd | 14.04 (0.45) e | 3.98 (0.39) ab | 3.41 (0.16) de |
| Pera Cristal Toro | 104.92 (6.30) cd | September | 2.11 (0.14) de | 3.28 (0.29) b | 1.24 (0.10) a | 13.64 (0.62) bcde | 4.38 (0.30) bc | 3.15 (0.29) abcde |
| Pera Cristal Peñacaball. | 125.32 (6.49) f | September | 0.41 (0.06) b | 3.62 (0.34) b | 1.71 (0.11) b | 12.76 (0.57) ab | 4.29 (0.37) bc | 2.76 (0.33) a |
| Pera de Manteca | 94.52 (4.16) bc | September | 3.01 (0.34) fg | 10.14 (0.63) g | 3.10 (0.23) g | 12.93 (0.43) abc | 4.16 (0.23) abc | 2.94 (0.41) abcd |
| Pera de Roma | 115.97 (5.41) ef | September | 2.83 (0.21) f | 5.36 (0.40) d | 2.37 (0.14) e | 13.43 (0.56) abcde | 4.09 (0.21) abc | 3.17 (0.24) abcde |
| Pera de San Juan | 94.50 (4.92) bc | June | 3.24 (0.26) g | 10.07 (0.65) g | 3.12 (0.16) g | 14.12 (0.62) e | 4.42 (0.42) bc | 3.40 (0.29) cde |
| Pera del País | 91.90 (5.38) b | September | 1.21 (0.17) c | 5.07 (0.41) cd | 1.85 (0.09) bc | 13.82 (0.37) cde | 4.37 (0.32) bc | 2.82 (0.32) a |
| Pera Temprana | 136.57 (7.67) g | September | 4.56 (0.33) i | 7.61 (0.43) e | 2.71 (0.15) f | 12.67 (0.44) a | 4.15 (0.26) abc | 2.93 (0.40) abc |
ANOVA, analysis of variance; a–i Different letters in the same column indicate significant differences LSD (p < 0.05).
Table 6.
Some qualitative fruit parameters in pear cultivars of the Central–West Iberian Peninsula.
| Cultivar | Position of Maximum Fruit Diameter | Profile of Fruit Sides | Ground Color of Fruit Skin | Relative Area of Over-Color | Russet on Fruit Skin |
|---|---|---|---|---|---|
| Bella Angelina | Clearly towards calyx | Concave | Yellow green | Medium | No |
| Cermeño Común | Slightly towards calyx | Convex | Yellow green | Medium | No |
| Cermeño Verde | In the middle | Convex | Yellow green | Medium | No |
| De Invierno | Slightly towards calyx | Convex | Green | Absent or very small | No |
| Don Guindo | Slightly towards calyx | Convex | Yellow green | Medium | No |
| Limonera | Slightly towards calyx | Straight | Yellow green | Small | No |
| Muslo de Dama | Clearly towards calyx | Concave | Green | Absent or very small | No |
| Pera de Agua | In the middle | Convex | Yellow green | Absent or very small | No |
| Blanquilla de Aranjuez | In the middle | Convex | Yellow green | Absent or very small | No |
| Pera Canela | Slightly towards calyx | Convex | Yellow | Absent or very small/Small | No |
| Pera Cristal Toro | Clearly towards calyx | Convex | Green | Medium | No |
| Pera Cristal Peñacaball. | In the middle | Convex | Green | Small | Yes |
| Pera de Manteca | Slightly towards calyx | Convex | Yellow green | Absent or very small | No |
| Pera de Roma | Slightly towards calyx | Convex | Green | Absent or very small | No |
| Pera de San Juan | Slightly towards calyx | Convex | Green | Medium | No |
| Pera del País | Slightly towards calyx | Convex | Yellow | Medium/Small | No |
| Pera Temprana | In the middle | Convex | Yellow | Medium | No |
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Pérez-Sánchez, R.; Morales-Corts, M.R. Agromorphological and Chemical Characterization of Pear Cultivars Grown in Central–West Iberian Peninsula. Agronomy 2023, 13, 2993. https://doi.org/10.3390/agronomy13122993
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Pérez-Sánchez R, Morales-Corts MR. Agromorphological and Chemical Characterization of Pear Cultivars Grown in Central–West Iberian Peninsula. Agronomy. 2023; 13(12):2993. https://doi.org/10.3390/agronomy13122993
Chicago/Turabian StylePérez-Sánchez, Rodrigo, and María Remedios Morales-Corts. 2023. "Agromorphological and Chemical Characterization of Pear Cultivars Grown in Central–West Iberian Peninsula" Agronomy 13, no. 12: 2993. https://doi.org/10.3390/agronomy13122993
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