Hydraulic conductivity and native embolism of Geneva® Series apple rootstocks measured by the XYL'EM-Plus® embolism meter

Most commercial apple orchards are established on either Marubakaido (Malus prunifolia Borkh.) (high vigor), M-9 (Malus pumila) (low vigor), or a combination of both rootstocks through the intergrafting technique. The Geneva® Series rootstocks were developed as an alternative to orchards modernization. The vigor of rootstocks influences the anatomical xylem formation and, therefore, the canopy cultivar's hydraulic conductivity. When affected by embolism, hydraulic conductivity harms plant metabolism, reducing crop yield and fruit quality. This study aimed to evaluate four Geneva® Series rootstocks with potential use in southern Brazil, in terms of hydraulic conductivity (K) and percentage loss of conductance (PLC), during the winter period in two different years. The G.213 rootstock presented the best performance for the variables analyzed; however, higher values of xylem functionality loss were observed in G.814.

Natural parasitism in fruit fly (Diptera: Tephritidae) and interaction with wild hosts surrounding apple orchards adjacent to Atlantic Forest fragments in Paraná State, Brazil / Parasitismo natural de mosca-das-frutas (Diptera: Tephritidae) e interação com hospedeiros silvestres em pomares de macieira adjacentes a fragmentos de Mata Atlântica no Estado do Paraná, Brasil

Abstract The South American fruit fly, Anastrepha fraterculus (Wiedemann, 1830) (Diptera: Tephritidae), is an important pest in the subtropical region of Brazil. This insect has tritrophic relation between wild fruits and parasitoids and is associated with apple (Malus domestica Borkh.) orchards adjacent to the Atlantic Forest in Paraná. We thus investigated the degree of infestation of the fruit fly and natural parasitism in wild and cultivated fruits surrounding apple orchards. For this purpose, we collected fruits of Acca sellowiana (Berg.) Burret, Campomanesia xanthocarpa (Mart), Eugenia uniflora L., Eugenia pyriformis Cambessèdes, Psidium cattleianum Sabine, Psidium guajava (L.), Annona neosericea Rainer and Eriobotrya japonica (Thumb) in apple orchards adjacent to the Atlantic Forest located in Campo do Tenente, Lapa and Porto Amazonas counties. In total, we collected 18,289 fruits during four growing years. The occurrence of A. fraterculus depends on the susceptible period of apple fruits. A. sellowiana and P. cattleianum were considered primary fruit fly multipliers and P. guajava was secondary, all occurring after the apple harvest (IS period). The group of parasitoids with A. fraterculus was Aganaspis pelleranoi (Brèthes, 1924) (Hymenoptera: Figitidae), Opius bellus (Gahan, 1930), Doryctobracon areolatus (Szépligeti, 1911) and Doryctobracon brasiliensis (Szépligeti, 1911) (Hymenoptera: Braconidae) all of which are first records in the Atlantic Forest in Paraná. First record of O. bellus occurring in the State of Paraná, as well as, first record of the tritrophic association between host plant A. neosericea, parasitoids D. areolatus and O. bellus and fruit fly A. fraterculus. The host P. cattleianum stood out among the Myrtaceae species in regard to the high diversity of parasitoid species (81% of parasitoids). The total number of Figitidae species (76.5%) was higher than that of Braconidae species. The influence of climatic events in southern Brazil on wild fruit production should be further studied to understand the association of A. fraterculus with the tritrophic relationship.

Resumo Mosca-das-frutas sul-americana, Anastrepha fraterculus (Wiedemann, 1830) (Diptera: Tephritidae), é uma importante praga da região subtropical do Brasil. Este inseto tem relação tritrófico entre frutos silvestres e parasitoides e está associado a pomares de macieiras (Malus domestica Borkh.) adjacentes à Mata Atlântica no Paraná. Assim, investigamos o grau de infestação da mosca-das-frutas e o parasitismo natural em frutas silvestres e cultivadas ao redor de pomares de maçã. Para tanto, foram coletados frutos de Acca sellowiana (Berg.) Burret, Campomanesia xanthocarpa (Mart), Eugenia uniflora L., Eugenia pyriformis Cambessèdes, Psidium cattleianum Sabine, Psidium guajava (L.), Annona neosericea Rainer e Eriobotrya japonica (Thumb) em pomares de maçã adjacentes à Mata Atlântica localizados nos municípios de Campo do Tenente, Lapa e Porto Amazonas. No total, coletamos 18.289 frutos durante quatro anos de cultivo. A ocorrência de A. fraterculus depende do período de suscetibilidade dos frutos da maçã. A. sellowiana e P. cattleianum foram considerados multiplicadores primários de mosca-das-frutas e P. guajava foi secundário, todos ocorrendo após a colheita da maçã (período IS). Os parasitóides a associados a A. fraterculus foram Aganaspis pelleranoi (Brèthes, 1924) (Hymenoptera: Figitidae), Opius bellus (Gahan, 1930), Doryctobracon areolatus (Szépligeti, 1911) e Doryctobracon brasiliensis (Szépligeti, 1911) (Hymenoptera: Braconidae), todos os quais são primeiros registros na Mata Atlântica no Paraná. Primeiro registro de O. bellus ocorrendo no Estado do Paraná, assim como, primeiro registro da associação tritrófica entre o hospedeiro A. neosericea, parasitoides D. areolatus e O. bellus e mosca-das-frutas A. fraterculus. O hospedeiro P. cattleianum se destacou entre as espécies de Myrtaceae pela alta diversidade de parasitóides associados (81% dos parasitóides). O número total de espécies de Figitidae (76,5%) foi superior ao de espécies de Braconidae. A influência de eventos climáticos no sul do Brasil na produção de frutas silvestres deve ser mais estudada para entender a associação de A. fraterculus com a relação tritrófica.

Natural parasitism in fruit fly (Diptera: Tephritidae) and interaction with wild hosts surrounding apple orchards adjacent to Atlantic Forest fragments in Paraná State, Brazil

Abstract The South American fruit fly, Anastrepha fraterculus (Wiedemann, 1830) (Diptera: Tephritidae), is an important pest in the subtropical region of Brazil. This insect has tritrophic relation between wild fruits and parasitoids and is associated with apple (Malus domestica Borkh.) orchards adjacent to the Atlantic Forest in Paraná. We thus investigated the degree of infestation of the fruit fly and natural parasitism in wild and cultivated fruits surrounding apple orchards. For this purpose, we collected fruits of Acca sellowiana (Berg.) Burret, Campomanesia xanthocarpa (Mart), Eugenia uniflora L., Eugenia pyriformis Cambessèdes, Psidium cattleianum Sabine, Psidium guajava (L.), Annona neosericea Rainer and Eriobotrya japonica (Thumb) in apple orchards adjacent to the Atlantic Forest located in Campo do Tenente, Lapa and Porto Amazonas counties. In total, we collected 18,289 fruits during four growing years. The occurrence of A. fraterculus depends on the susceptible period of apple fruits. A. sellowiana and P. cattleianum were considered primary fruit fly multipliers and P. guajava was secondary, all occurring after the apple harvest (IS period). The group of parasitoids with A. fraterculus was Aganaspis pelleranoi (Brèthes, 1924) (Hymenoptera: Figitidae), Opius bellus (Gahan, 1930), Doryctobracon areolatus (Szépligeti, 1911) and Doryctobracon brasiliensis (Szépligeti, 1911) (Hymenoptera: Braconidae) all of which are first records in the Atlantic Forest in Paraná. First record of O. bellus occurring in the State of Paraná, as well as, first record of the tritrophic association between host plant A. neosericea, parasitoids D. areolatus and O. bellus and fruit fly A. fraterculus. The host P. cattleianum stood out among the Myrtaceae species in regard to the high diversity of parasitoid species (81% of parasitoids). The total number of Figitidae species (76.5%) was higher than that of Braconidae species. The influence of climatic events in southern Brazil on wild fruit production should be further studied to understand the association of A. fraterculus with the tritrophic relationship.

Resumo Mosca-das-frutas sul-americana, Anastrepha fraterculus (Wiedemann, 1830) (Diptera: Tephritidae), é uma importante praga da região subtropical do Brasil. Este inseto tem relação tritrófico entre frutos silvestres e parasitoides e está associado a pomares de macieiras (Malus domestica Borkh.) adjacentes à Mata Atlântica no Paraná. Assim, investigamos o grau de infestação da mosca-das-frutas e o parasitismo natural em frutas silvestres e cultivadas ao redor de pomares de maçã. Para tanto, foram coletados frutos de Acca sellowiana (Berg.) Burret, Campomanesia xanthocarpa (Mart), Eugenia uniflora L., Eugenia pyriformis Cambessèdes, Psidium cattleianum Sabine, Psidium guajava (L.), Annona neosericea Rainer e Eriobotrya japonica (Thumb) em pomares de maçã adjacentes à Mata Atlântica localizados nos municípios de Campo do Tenente, Lapa e Porto Amazonas. No total, coletamos 18.289 frutos durante quatro anos de cultivo. A ocorrência de A. fraterculus depende do período de suscetibilidade dos frutos da maçã. A. sellowiana e P. cattleianum foram considerados multiplicadores primários de mosca-das-frutas e P. guajava foi secundário, todos ocorrendo após a colheita da maçã (período IS). Os parasitóides a associados a A. fraterculus foram Aganaspis pelleranoi (Brèthes, 1924) (Hymenoptera: Figitidae), Opius bellus (Gahan, 1930), Doryctobracon areolatus (Szépligeti, 1911) e Doryctobracon brasiliensis (Szépligeti, 1911) (Hymenoptera: Braconidae), todos os quais são primeiros registros na Mata Atlântica no Paraná. Primeiro registro de O. bellus ocorrendo no Estado do Paraná, assim como, primeiro registro da associação tritrófica entre o hospedeiro A. neosericea, parasitoides D. areolatus e O. bellus e mosca-das-frutas A. fraterculus. O hospedeiro P. cattleianum se destacou entre as espécies de Myrtaceae pela alta diversidade de parasitóides associados (81% dos parasitóides). O número total de espécies de Figitidae (76,5%) foi superior ao de espécies de Braconidae. A influência de eventos climáticos no sul do Brasil na produção de frutas silvestres deve ser mais estudada para entender a associação de A. fraterculus com a relação tritrófica.

Natural parasitism in fruit fly (Diptera: Tephritidae) and interaction with wild hosts surrounding apple orchards adjacent to Atlantic Forest fragments in Paraná State, Brazil / Parasitismo natural de mosca-das-frutas (Diptera: Tephritidae) e interação com hospedeiros silvestres em pomares de macieira adjacentes a fragmentos de Mata Atlântica no Estado do Paraná, Brasil

The South American fruit fly, Anastrepha fraterculus (Wiedemann, 1830) (Diptera: Tephritidae), is an important pest in the subtropical region of Brazil. This insect has tritrophic relation between wild fruits and parasitoids and is associated with apple (Malus domestica Borkh.) orchards adjacent to the Atlantic Forest in Paraná. We thus investigated the degree of infestation of the fruit fly and natural parasitism in wild and cultivated fruits surrounding apple orchards. For this purpose, we collected fruits of Acca sellowiana (Berg.) Burret, Campomanesia xanthocarpa (Mart), Eugenia uniflora L., Eugenia pyriformis Cambessèdes, Psidium cattleianum Sabine, Psidium guajava (L.), Annona neosericea Rainer and Eriobotrya japonica (Thumb) in apple orchards adjacent to the Atlantic Forest located in Campo do Tenente, Lapa and Porto Amazonas counties. In total, we collected 18,289 fruits during four growing years. The occurrence of A. fraterculus depends on the susceptible period of apple fruits. A. sellowiana and P. cattleianum were considered primary fruit fly multipliers and P. guajava was secondary, all occurring after the apple harvest (IS period). The group of parasitoids with A. fraterculus was Aganaspis pelleranoi (Brèthes, 1924) (Hymenoptera: Figitidae), Opius bellus (Gahan, 1930), Doryctobracon areolatus (Szépligeti, 1911) and Doryctobracon brasiliensis (Szépligeti, 1911) (Hymenoptera: Braconidae) all of which are first records in the Atlantic Forest in Paraná. First record of O. bellus occurring in the State of Paraná, as well as, first record of the tritrophic association between host plant A. neosericea, parasitoids D. areolatus and O. bellus and fruit fly A. fraterculus. The host P. cattleianum stood out among the Myrtaceae species in regard to the high diversity of parasitoid species (81% of parasitoids). The total number of Figitidae species (76.5%) was higher [...].

Mosca-das-frutas sul-americana, Anastrepha fraterculus (Wiedemann, 1830) (Diptera: Tephritidae), é uma importante praga da região subtropical do Brasil. Este inseto tem relação tritrófico entre frutos silvestres e parasitoides e está associado a pomares de macieiras (Malus domestica Borkh.) adjacentes à Mata Atlântica no Paraná. Assim, investigamos o grau de infestação da mosca-das-frutas e o parasitismo natural em frutas silvestres e cultivadas ao redor de pomares de maçã. Para tanto, foram coletados frutos de Acca sellowiana (Berg.) Burret, Campomanesia xanthocarpa (Mart), Eugenia uniflora L., Eugenia pyriformis Cambessèdes, Psidium cattleianum Sabine, Psidium guajava (L.), Annona neosericea Rainer e Eriobotrya japonica (Thumb) em pomares de maçã adjacentes à Mata Atlântica localizados nos municípios de Campo do Tenente, Lapa e Porto Amazonas. No total, coletamos 18.289 frutos durante quatro anos de cultivo. A ocorrência de A. fraterculus depende do período de suscetibilidade dos frutos da maçã. A. sellowiana e P. cattleianum foram considerados multiplicadores primários de mosca-das-frutas e P. guajava foi secundário, todos ocorrendo após a colheita da maçã (período IS). Os parasitóides a associados a A. fraterculus foram Aganaspis pelleranoi (Brèthes, 1924) (Hymenoptera: Figitidae), Opius bellus (Gahan, 1930), Doryctobracon areolatus (Szépligeti, 1911) e Doryctobracon brasiliensis (Szépligeti, 1911) (Hymenoptera: Braconidae), todos os quais são primeiros registros na Mata Atlântica no Paraná. Primeiro registro de O. bellus ocorrendo no Estado do Paraná, assim como, primeiro registro da associação tritrófica entre o hospedeiro A. neosericea, parasitoides D. areolatus e O. bellus e mosca-das-frutas A. fraterculus. O hospedeiro P. cattleianum se destacou entre as espécies de Myrtaceae pela alta diversidade de parasitóides associados (81% dos parasitóides). O número total de espécies de Figitidae (76,5%) foi superior [...].

Natural parasitism in fruit fly (Diptera: Tephritidae) and interaction with wild hosts surrounding apple orchards adjacent to Atlantic Forest fragments in Paraná State, Brazil / Parasitismo natural de mosca-das-frutas (Diptera: Tephritidae) e interação com hospedeiros silvestres em pomares de macieira adjacentes a fragmentos de Mata Atlântica no Estado do Paraná, Brasil

The South American fruit fly, Anastrepha fraterculus (Wiedemann, 1830) (Diptera: Tephritidae), is an important pest in the subtropical region of Brazil. This insect has tritrophic relation between wild fruits and parasitoids and is associated with apple (Malus domestica Borkh.) orchards adjacent to the Atlantic Forest in Paraná. We thus investigated the degree of infestation of the fruit fly and natural parasitism in wild and cultivated fruits surrounding apple orchards. For this purpose, we collected fruits of Acca sellowiana (Berg.) Burret, Campomanesia xanthocarpa (Mart), Eugenia uniflora L., Eugenia pyriformis Cambessèdes, Psidium cattleianum Sabine, Psidium guajava (L.), Annona neosericea Rainer and Eriobotrya japonica (Thumb) in apple orchards adjacent to the Atlantic Forest located in Campo do Tenente, Lapa and Porto Amazonas counties. In total, we collected 18,289 fruits during four growing years. The occurrence of A. fraterculus depends on the susceptible period of apple fruits. A. sellowiana and P. cattleianum were considered primary fruit fly multipliers and P. guajava was secondary, all occurring after the apple harvest (IS period). The group of parasitoids with A. fraterculus was Aganaspis pelleranoi (Brèthes, 1924) (Hymenoptera: Figitidae), Opius bellus (Gahan, 1930), Doryctobracon areolatus (Szépligeti, 1911) and Doryctobracon brasiliensis (Szépligeti, 1911) (Hymenoptera: Braconidae) all of which are first records in the Atlantic Forest in Paraná. First record of O. bellus occurring in the State of Paraná, as well as, first record of the tritrophic association between host plant A. neosericea, parasitoids D. areolatus and O. bellus and fruit fly A. fraterculus. The host P. cattleianum stood out among the Myrtaceae species in regard to the high diversity of parasitoid species (81% of parasitoids). The total number of Figitidae species (76.5%) was higher [...].(AU)

Mosca-das-frutas sul-americana, Anastrepha fraterculus (Wiedemann, 1830) (Diptera: Tephritidae), é uma importante praga da região subtropical do Brasil. Este inseto tem relação tritrófico entre frutos silvestres e parasitoides e está associado a pomares de macieiras (Malus domestica Borkh.) adjacentes à Mata Atlântica no Paraná. Assim, investigamos o grau de infestação da mosca-das-frutas e o parasitismo natural em frutas silvestres e cultivadas ao redor de pomares de maçã. Para tanto, foram coletados frutos de Acca sellowiana (Berg.) Burret, Campomanesia xanthocarpa (Mart), Eugenia uniflora L., Eugenia pyriformis Cambessèdes, Psidium cattleianum Sabine, Psidium guajava (L.), Annona neosericea Rainer e Eriobotrya japonica (Thumb) em pomares de maçã adjacentes à Mata Atlântica localizados nos municípios de Campo do Tenente, Lapa e Porto Amazonas. No total, coletamos 18.289 frutos durante quatro anos de cultivo. A ocorrência de A. fraterculus depende do período de suscetibilidade dos frutos da maçã. A. sellowiana e P. cattleianum foram considerados multiplicadores primários de mosca-das-frutas e P. guajava foi secundário, todos ocorrendo após a colheita da maçã (período IS). Os parasitóides a associados a A. fraterculus foram Aganaspis pelleranoi (Brèthes, 1924) (Hymenoptera: Figitidae), Opius bellus (Gahan, 1930), Doryctobracon areolatus (Szépligeti, 1911) e Doryctobracon brasiliensis (Szépligeti, 1911) (Hymenoptera: Braconidae), todos os quais são primeiros registros na Mata Atlântica no Paraná. Primeiro registro de O. bellus ocorrendo no Estado do Paraná, assim como, primeiro registro da associação tritrófica entre o hospedeiro A. neosericea, parasitoides D. areolatus e O. bellus e mosca-das-frutas A. fraterculus. O hospedeiro P. cattleianum se destacou entre as espécies de Myrtaceae pela alta diversidade de parasitóides associados (81% dos parasitóides). O número total de espécies de Figitidae (76,5%) foi superior [...].(AU)

Effects of an Auxin and a brassinosteroid on physical, chemical and biochemical attributes of Galaxy apples / Ação da auxina e do brassinosteroide nos atributos físico-químicos e bioquímicos de maçãs ‘Galaxy

The aim of this study was to study the effect of the auxin naphthalene acetic acid (NAA) and the brassinosteroid 28-homocastasterone (28-HCS) applied every 15 days (harvest 2015/16) or every 21 days (harvest 2016/17) after full bloom, on the physical, chemical and biochemical attributes of the ‘Galaxy apples. The study was performed at a commercial orchard at Vacaria county, Rio Grande do Sul State, Brazil. The following treatments were applied: water (control), NAA (0.1%), 28-HCS (10‒6 M) and NAA (0.1%) + 28-HCS (10‒6 M). For this purpose, 300 μL of the plant growth regulator solutions were applied to the fruit peduncles. Fruits treated with NAA every 21 days presented higher starch-iodine index and lower total soluble solids (TSS), titratable acidity (TA), lightness index (L) and hue angle (h°) than 28-HCS-treated fruits. Fruits treated every 15 days with NAA presented reduced skin rupture force (SRF), total antioxidant activities (TAA) of the skin and flesh, and hydrogen peroxide content compared to the control fruits. In addition, NAA application every 15 and 21 days resulted in increased anthocyanin content in the skin. Application of NAA + 28-HCS reduced superoxide dismutase activity. 28-HCS applications increased TSS, color attributes (C and h°) of the skin, total antioxidant activity of the skin and flesh and peroxidase activity compared to control fruits. These results are expected to help to understand how plant growth regulators affect apple quality. In addition, results described here are also expected to help on the development of strategies to reduce post harvest losses and to increase fruit shelf life.(AU)

O objetivo deste estudo foi avaliar a ação do ácido naftaleno acético (ANA) e do brassinosteroide (catasterona), aplicados a cada 15 (safra 2015/16) ou 21 (safra 2016/17) dias a partir dos 40 dias após a plena floração, nos atributos físico-químicos e bioquímicos de maçãs ‘Galaxy. O estudo foi realizado em um pomar comercial de macieiras ‘Galaxy no município de Vacaria, RS. Os tratamentos avaliados foram: água (controle), ANA (0,1%), catasterona (10‒6 M) e ANA (0,1%) + catasterona (10‒6 M). As aplicações foram realizadas no pedúnculo dos frutos, utilizando 300 µL de solução por pedúnculo. Frutos tratados com ANA a cada 21 dias tiveram maior índice de iodo-amido e menores valores de sólidos solúveis (SS), acidez titulável e dos atributos de cor L e ângulo hue (h°) do que os frutos tratados com catasterona. Aplicações de ANA a cada 15 dias reduziu a força de ruptura da casca (FRC), atividade antioxidante (AAT) da casca, da polpa e conteúdo de peróxido de hidrogênio. Além disso, ANA aplicada a cada 15 ou 21 dias aumentaram o teor de antocianinas na casca. ANA + catasterona reduziu a atividade da enzima superóxido dismutase. Entretanto, aplicações de catasterona a cada 15 dias aumentou o teor de SS, atributos de cor (C e h°) na casca, atividade antioxidante da casca e da polpa, compostos fenólicos totais (CFT) e atividade da enzima peroxidase dos frutos de maçãs. Portanto, estudos adicionais devem ser realizados para confirmar a ação desses fitorreguladores na manutenção da qualidade e redução das perdas pós-colheitas de maçãs ‘Galaxy.(AU)

Phenotypic and molecular characterization of apple (Malus × domestica Borkh) genetic resources in Greece

The phenotypic and genetic analysis of apple (Malus × domestica Borkh) genotypes is essential for breeding species. Information on the morphology and genetic structure of apple offers significant help for germplasm maintenance and selection of suitable material to breed superior cultivars. This study shows the results of an investigation on the morphology and the genetic diversity for 19 apple cultivars, which are preserved in an ex situ collection in Naoussa, Central Macedonia, Greece. Information was recorded over a 5-year period for 47 traits describing plant morphology and phenotype, as well as leaf and fruit quality. Data were analyzed using the principal component analysis (PCA) method. The Euclidean distance metric and the Wards agglomeration method were used in an unsupervised hierarchical cluster analysis of all cultivars. The cultivars were grouped into four main clusters, suggesting that the characterized apple collection has a high potential for specific breeding goals. Furthermore, the cultivars were genotyped using seven microsatellite primers. Moderate levels of polymorphism were detected, and 38 distinctive alleles (5.4 alleles per primer pair) were identified. Both multivariate clustering approach (phenotypic data) and the genetic distance clustering approach (genetic data) grouped the apple cultivars according to their type. Hence, these data could be used for protection or patenting processes of existing or new apple cultivars carried out by the EU-Community Plant Variety Office.(AU)

Phenotypic and molecular characterization of apple (Malus × domestica Borkh) genetic resources in Greece

ABSTRACT: The phenotypic and genetic analysis of apple (Malus × domestica Borkh) genotypes is essential for breeding species. Information on the morphology and genetic structure of apple offers significant help for germplasm maintenance and selection of suitable material to breed superior cultivars. This study shows the results of an investigation on the morphology and the genetic diversity for 19 apple cultivars, which are preserved in an ex situ collection in Naoussa, Central Macedonia, Greece. Information was recorded over a 5-year period for 47 traits describing plant morphology and phenotype, as well as leaf and fruit quality. Data were analyzed using the principal component analysis (PCA) method. The Euclidean distance metric and the Wards agglomeration method were used in an unsupervised hierarchical cluster analysis of all cultivars. The cultivars were grouped into four main clusters, suggesting that the characterized apple collection has a high potential for specific breeding goals. Furthermore, the cultivars were genotyped using seven microsatellite primers. Moderate levels of polymorphism were detected, and 38 distinctive alleles (5.4 alleles per primer pair) were identified. Both multivariate clustering approach (phenotypic data) and the genetic distance clustering approach (genetic data) grouped the apple cultivars according to their type. Hence, these data could be used for protection or patenting processes of existing or new apple cultivars carried out by the EU-Community Plant Variety Office.

Phenotypic and molecular characterization of apple (Malus × domestica Borkh) genetic resources in Greece

ABSTRACT: The phenotypic and genetic analysis of apple (Malus × domestica Borkh) genotypes is essential for breeding species. Information on the morphology and genetic structure of apple offers significant help for germplasm maintenance and selection of suitable material to breed superior cultivars. This study shows the results of an investigation on the morphology and the genetic diversity for 19 apple cultivars, which are preserved in an ex situ collection in Naoussa, Central Macedonia, Greece. Information was recorded over a 5-year period for 47 traits describing plant morphology and phenotype, as well as leaf and fruit quality. Data were analyzed using the principal component analysis (PCA) method. The Euclidean distance metric and the Wards agglomeration method were used in an unsupervised hierarchical cluster analysis of all cultivars. The cultivars were grouped into four main clusters, suggesting that the characterized apple collection has a high potential for specific breeding goals. Furthermore, the cultivars were genotyped using seven microsatellite primers. Moderate levels of polymorphism were detected, and 38 distinctive alleles (5.4 alleles per primer pair) were identified. Both multivariate clustering approach (phenotypic data) and the genetic distance clustering approach (genetic data) grouped the apple cultivars according to their type. Hence, these data could be used for protection or patenting processes of existing or new apple cultivars carried out by the EU-Community Plant Variety Office.

Quality of ‘Fuji Suprema apples influenced by long-term annual addition of phosphorus to the soil / Qualidade de frutos de maç㠑Fuji Suprema influenciada pela adição anual de longo prazo de fósforo ao solo

Fertilization of apple orchards with phosphorus (P) has received less attention than with nitrogen and potassium. In Brazil, the information about apple response to soil P addition is meager. The objective of this study was to evaluate the long-term effect of annual soil P addition on quality and mineral composition of apple fruits. The experiment started in 2010, in a commercial orchard located in the São Joaquim, Southern of Brazil. The orchard consisted of ́Fuji Suprema, planted in high-density on a Haplumbrept soil. Treatments consisted of 0, 40, 80, 120 and 160kg ha-1 P2O5 applied annually starting in 2010 broadcast over the soil surface along the tree row. Evaluations were performed from 2012/2013 through 2014/2015 growing seasons. We harvested three samples from each experimental unit. One sample was cold stored in a controlled atmosphere chamber for six months; the others were immediately evaluated for firmness, total soluble solids, titratable acidity (TA), skin color, and the concentrations of N, P, K, Ca and Mg in the fruit flesh. Application of P to the soil affected only flesh firmness at harvest and TA after six months of storage in the 2012/2013 season, as well as firmness after six months of storage in the 2013/2014 season. In the 2014/2015 season, the addition of P reduced fruit color but only at harvest. Addition of P to the soil affected the levels of P in the fruit in the 2012/2013 season, as well as N and the N/Ca ratio of fruit in the 2014/2015 season. Overall, attributes related to fruit quality of cultivar Fuji Suprema were slightly affected by long-term annual addition of P to the soil.(AU)

A adubação com fósforo (P) em pomares de maçã tem recebido menos atenção que adubações com nitrogênio e potássio. No Brasil, as informações sobre a resposta da macieira a adição de P ao solo é escassa. O objetivo deste estudo foi avaliar o efeito a longo prazo da adição anual de P ao solo na qualidade e composição mineral de maçãs. O experimento iniciou em 2010, num pomar comercial localizado no município de São Joaquim, Sul do Brasil, com a cultivar ‘Fuji Suprema, instalado em alta densidade (aproximadamente 2.000 plantas ha-1) em um solo Haplumbrept. Os tratamentos consistiram de 0, 40, 80, 120 e 160kg ha-1 P2O5 aplicados anualmente a partir de 2010, na superfície do solo ao longo da fileira das árvores. As avaliações foram realizadas nas estações de crescimento de 2012/2013 até 2014/2015. Três amostras de 10 frutos de cada unidade experimental foram colhidas. Uma amostra foi armazenada em uma câmara fria de atmosfera controlada por seis meses; os outros foram imediatamente avaliados quanto à firmeza, sólidos solúveis totais, acidez titulável (AT), cor da epiderme e as concentrações de N, P, K, Ca e Mg na polpa dos frutos. A aplicação de P ao solo afetou apenas a firmeza de polpa na colheita e AT após seis meses de armazenamento na safra 2012/2013, bem como a firmeza após seis meses de armazenamento na safra 2013/2014. Na safra 2014/2015, a adição de P reduziu a cor dos frutos, mas apenas na colheita. A adição de P ao solo afetou os níveis de P nos frutos da safra 2012/2013, bem como N e a relação N / Ca de frutas na safra 2014/2015. Em geral, os atributos relacionados à qualidade dos frutos da cultivar Fuji Suprema foram ligeiramente afetados pela adição anual prolongada de P ao solo.(AU)

A smartphone-based apple yield estimation application using imaging features and the ANN method in mature period

Apple yield estimation using a smartphone with image processing technology offers advantages such as low cost, quick access and simple operation. This article proposes distribution framework consisting of the acquisition of fruit tree images, yield prediction in smarphone client, data processing and model calculation in server client for estimating the potential fruit yield. An image processing method was designed including the core steps of image segmentation with R/B value combined with V value and circle-fitting using curvature analysis. This method enabled four parameters to be obtained, namely, total identified pixel area (TP), fitting circle amount (FC), average radius of the fitting circle (RC) and small polygon pixel area (SP). A individual tree yield estimation model on an ANN (Artificial Neural Network) was developed with three layers, four input parameters, 14 hidden neurons, and one output parameter. The system was used on an experimental Fuji apple (Malus domestica Borkh. cv. Red Fuji) orchard. Twenty-six tree samples were selected from a total of 80 trees according to the multiples of the number three for the establishment model, whereby 21 groups of data were trained and 5 groups o data were validated. The R2 value for the training datasets was 0.996 and the relative root mean squared error (RRMSE) value 0.063. The RRMSE value for the validation dataset was 0.284 Furthermore, a yield map with 80 apple trees was generated, and the space distribution o the yield was identified. It provided appreciable decision support for site-specific management.(AU)

Quality of Fuji Suprema apples influenced by long-term annual addition of phosphorus to the soil

ABSTRACT: Fertilization of apple orchards with phosphorus (P) has received less attention than with nitrogen and potassium. In Brazil, the information about apple response to soil P addition is meager. The objective of this study was to evaluate the long-term effect of annual soil P addition on quality and mineral composition of apple fruits. The experiment started in 2010, in a commercial orchard located in the São Joaquim, Southern of Brazil. The orchard consisted of ´Fuji Suprema, planted in high-density on a Haplumbrept soil. Treatments consisted of 0, 40, 80, 120 and 160kg ha-1 P2O5 applied annually starting in 2010 broadcast over the soil surface along the tree row. Evaluations were performed from 2012/2013 through 2014/2015 growing seasons. We harvested three samples from each experimental unit. One sample was cold stored in a controlled atmosphere chamber for six months; the others were immediately evaluated for firmness, total soluble solids, titratable acidity (TA), skin color, and the concentrations of N, P, K, Ca and Mg in the fruit flesh. Application of P to the soil affected only flesh firmness at harvest and TA after six months of storage in the 2012/2013 season, as well as firmness after six months of storage in the 2013/2014 season. In the 2014/2015 season, the addition of P reduced fruit color but only at harvest. Addition of P to the soil affected the levels of P in the fruit in the 2012/2013 season, as well as N and the N/Ca ratio of fruit in the 2014/2015 season. Overall, attributes related to fruit quality of cultivar Fuji Suprema were slightly affected by long-term annual addition of P to the soil.

RESUMO: A adubação com fósforo (P) em pomares de maçã tem recebido menos atenção que adubações com nitrogênio e potássio. No Brasil, as informações sobre a resposta da macieira a adição de P ao solo é escassa. O objetivo deste estudo foi avaliar o efeito a longo prazo da adição anual de P ao solo na qualidade e composição mineral de maçãs. O experimento iniciou em 2010, num pomar comercial localizado no município de São Joaquim, Sul do Brasil, com a cultivar Fuji Suprema, instalado em alta densidade (aproximadamente 2.000 plantas ha-1) em um solo Haplumbrept. Os tratamentos consistiram de 0, 40, 80, 120 e 160kg ha-1 P2O5 aplicados anualmente a partir de 2010, na superfície do solo ao longo da fileira das árvores. As avaliações foram realizadas nas estações de crescimento de 2012/2013 até 2014/2015. Três amostras de 10 frutos de cada unidade experimental foram colhidas. Uma amostra foi armazenada em uma câmara fria de atmosfera controlada por seis meses; os outros foram imediatamente avaliados quanto à firmeza, sólidos solúveis totais, acidez titulável (AT), cor da epiderme e as concentrações de N, P, K, Ca e Mg na polpa dos frutos. A aplicação de P ao solo afetou apenas a firmeza de polpa na colheita e AT após seis meses de armazenamento na safra 2012/2013, bem como a firmeza após seis meses de armazenamento na safra 2013/2014. Na safra 2014/2015, a adição de P reduziu a cor dos frutos, mas apenas na colheita. A adição de P ao solo afetou os níveis de P nos frutos da safra 2012/2013, bem como N e a relação N / Ca de frutas na safra 2014/2015. Em geral, os atributos relacionados à qualidade dos frutos da cultivar Fuji Suprema foram ligeiramente afetados pela adição anual prolongada de P ao solo.

A smartphone-based apple yield estimation application using imaging features and the ANN method in mature period

ABSTRACT: Apple yield estimation using a smartphone with image processing technology offers advantages such as low cost, quick access and simple operation. This article proposes distribution framework consisting of the acquisition of fruit tree images, yield prediction in smarphone client, data processing and model calculation in server client for estimating the potential fruit yield. An image processing method was designed including the core steps of image segmentation with R/B value combined with V value and circle-fitting using curvature analysis. This method enabled four parameters to be obtained, namely, total identified pixel area (TP), fitting circle amount (FC), average radius of the fitting circle (RC) and small polygon pixel area (SP). A individual tree yield estimation model on an ANN (Artificial Neural Network) was developed with three layers, four input parameters, 14 hidden neurons, and one output parameter. The system was used on an experimental Fuji apple (Malus domestica Borkh. cv. Red Fuji) orchard. Twenty-six tree samples were selected from a total of 80 trees according to the multiples of the number three for the establishment model, whereby 21 groups of data were trained and 5 groups o data were validated. The R2 value for the training datasets was 0.996 and the relative root mean squared error (RRMSE) value 0.063. The RRMSE value for the validation dataset was 0.284 Furthermore, a yield map with 80 apple trees was generated, and the space distribution o the yield was identified. It provided appreciable decision support for site-specific management.

A smartphone-based apple yield estimation application using imaging features and the ANN method in mature period

ABSTRACT: Apple yield estimation using a smartphone with image processing technology offers advantages such as low cost, quick access and simple operation. This article proposes distribution framework consisting of the acquisition of fruit tree images, yield prediction in smarphone client, data processing and model calculation in server client for estimating the potential fruit yield. An image processing method was designed including the core steps of image segmentation with R/B value combined with V value and circle-fitting using curvature analysis. This method enabled four parameters to be obtained, namely, total identified pixel area (TP), fitting circle amount (FC), average radius of the fitting circle (RC) and small polygon pixel area (SP). A individual tree yield estimation model on an ANN (Artificial Neural Network) was developed with three layers, four input parameters, 14 hidden neurons, and one output parameter. The system was used on an experimental Fuji apple (Malus domestica Borkh. cv. Red Fuji) orchard. Twenty-six tree samples were selected from a total of 80 trees according to the multiples of the number three for the establishment model, whereby 21 groups of data were trained and 5 groups o data were validated. The R2 value for the training datasets was 0.996 and the relative root mean squared error (RRMSE) value 0.063. The RRMSE value for the validation dataset was 0.284 Furthermore, a yield map with 80 apple trees was generated, and the space distribution o the yield was identified. It provided appreciable decision support for site-specific management.

Postharvest quality of Galaxy apples submitted to the treatment with 1-MCP and different cooling times between harvest and cold storage / Qualidade pós-colheita de maçãs ‘Galaxy’ submetidas ao tratamento com 1-MCP e diferentes tempos de resfriamento entre a colheita e o armazenamento refrigerado

ABSTRACT: In this research it was evaluated if the use of 1-methylcyclopropene (1-MCP), associated to different cooling times between the harvest and storage, replaces the pre-cooling in Galaxy apples. Treatments were arranged in a factorial scheme, combining the following factors: application of 1-MCP (with or without) and different times between harvest and cooling (24 hours, 96 hours, 144 hours and 192 hours in 2013; and 24 hours, 48 hours, 144 hours and 240 hours in 2014). After four months of cold storage (1.0±0.2°C/92±5% RH - Relative Humidity) were evaluated: flesh firmness, texture, titratable acidity (TA), soluble solids (SS) and skin color. Apples treated with 1-MCP showed greater flesh firmness, texture and SS, in both years, and more TA and lower incidence of mealy flesh compared to apples not treated with 1-MCP in 2013. The 1-MCP was effective in maintaining the fruit quality, even with the cooling delay of up to 240 hours. Cooling delay of 192 hours and 240 hours in Galaxy apples not treated with 1-MCP should be avoided because it reduces the quality of fruits.

RESUMO: Neste trabalho avaliamos se o uso de 1-metilciclopropeno (1-MCP), associado com diferentes tempos de resfriamento entre a colheita e o armazenamento, substitui o pré-resfriamento em maçãs Galaxy. Os tratamentos foram arranjados em esquema fatorial, combinando os fatores aplicação de 1-MCP (com ou sem) e diferentes tempos entre a colheita e o resfriamento (24h, 96h, 144h e 192h, em 2013; e 24h, 48h, 144h e 240h, em 2014). Após quatro meses de armazenamento refrigerado (1,0±0,2°C/92±5% de UR), foram avaliados: firmeza de polpa, textura, acidez titulável (AT), sólidos solúveis (SS) e cor da epiderme. As maçãs tratadas com 1-MCP apresentaram maior firmeza de polpa, textura e SS, em ambos os anos, e maior AT e menor incidência de polpa farinácea em comparação a maçãs não tratadas com 1-MCP, em 2013. O 1-MCP foi eficaz em manter a qualidade dos frutos, mesmo com o retardo do resfriamento em até 240h. O retardo do resfriamento de 192h e 240h em maçãs Galaxy não tratadas com 1-MCP deve ser evitado, pois diminui a qualidade dos frutos.

Postharvest quality of Galaxy apples submitted to the treatment with 1-MCP and different cooling times between harvest and cold storage / Qualidade pós-colheita de maçãs ‘Galaxy submetidas ao tratamento com 1-MCP e diferentes tempos de resfriamento entre a colheita e o armazenamento refrigerado

ABSTRACT: In this research it was evaluated if the use of 1-methylcyclopropene (1-MCP), associated to different cooling times between the harvest and storage, replaces the pre-cooling in Galaxy apples. Treatments were arranged in a factorial scheme, combining the following factors: application of 1-MCP (with or without) and different times between harvest and cooling (24 hours, 96 hours, 144 hours and 192 hours in 2013; and 24 hours, 48 hours, 144 hours and 240 hours in 2014). After four months of cold storage (1.0±0.2°C/92±5% RH - Relative Humidity) were evaluated: flesh firmness, texture, titratable acidity (TA), soluble solids (SS) and skin color. Apples treated with 1-MCP showed greater flesh firmness, texture and SS, in both years, and more TA and lower incidence of mealy flesh compared to apples not treated with 1-MCP in 2013. The 1-MCP was effective in maintaining the fruit quality, even with the cooling delay of up to 240 hours. Cooling delay of 192 hours and 240 hours in Galaxy apples not treated with 1-MCP should be avoided because it reduces the quality of fruits.(AU)

RESUMO: Neste trabalho avaliamos se o uso de 1-metilciclopropeno (1-MCP), associado com diferentes tempos de resfriamento entre a colheita e o armazenamento, substitui o pré-resfriamento em maçãs Galaxy. Os tratamentos foram arranjados em esquema fatorial, combinando os fatores aplicação de 1-MCP (com ou sem) e diferentes tempos entre a colheita e o resfriamento (24h, 96h, 144h e 192h, em 2013; e 24h, 48h, 144h e 240h, em 2014). Após quatro meses de armazenamento refrigerado (1,0±0,2°C/92±5% de UR), foram avaliados: firmeza de polpa, textura, acidez titulável (AT), sólidos solúveis (SS) e cor da epiderme. As maçãs tratadas com 1-MCP apresentaram maior firmeza de polpa, textura e SS, em ambos os anos, e maior AT e menor incidência de polpa farinácea em comparação a maçãs não tratadas com 1-MCP, em 2013. O 1-MCP foi eficaz em manter a qualidade dos frutos, mesmo com o retardo do resfriamento em até 240h. O retardo do resfriamento de 192h e 240h em maçãs Galaxy não tratadas com 1-MCP deve ser evitado, pois diminui a qualidade dos frutos.(AU)

Initial growth, production, and quality of fruits of apple trees as affected by irrigation and fertirrigation / Crescimento inicial, produção e qualidade de frutos de macieiras submetidas a irrigação e fertirrigação

This study aimed to evaluate nutrient content on leaves and fruit flesh, yield and quality of fruits, as well as apple tree growth as affected by the fertilizer physical form (conventional or fertirrigation) and water addition or not via irrigation. The experiment was carried out in São Joaquim, Southern of Brazil, during the 2012/2013 and 2013/2014 growing season. The orchard was planted in 2011 with Kinkas cultivar grafted over a Marubakaido rootstock, 1.666 trees ha-1. The eight replications of each treatment were allocated in the completely randomized block design. Treatments consisted of conventional solid soil fertilization (T1), irrigation + conventional solid soil fertilization (T2), irrigation + fertirrigation (T3), and fertirrigation (T4). From the daily averages of tensiometer readings in addition to the water soil retention the irrigation needs and the application time curve were determined. In 2012, 27 kg ha-1 of N was applied; in the following season, it 100 kg ha-1 of N and 150 kg ha-1 of K2O was applied. Fertilizers were split three times on treatments T1 and T2, and six times on treatments T3 and T4, from November through January. During the experimental period it many drought periods were observed. Irrigation and fertirrigation had no effect on initial apple tree growth. Irrigation did not affect the nutrient content in leaves or fruit flesh. Fruits from the T3 (irrigation + fertirrigation) presented the highest weight. Fruit yield, however, did not differ among treatments. Fertirrigation was the best form of nutrient application to the plants, but it is necessary to determine rates and times of application to obtain the maximum productive efficiency.(AU)

O presente trabalho objetivou avaliar o desenvolvimento inicial da macieira, os aspectos nutricionais, qualidade dos frutos em função da forma de aplicação dos fertilizantes e da adição ou não de água via irrigação. O experimento foi conduzido em São Joaquim durante as estações de crescimento 2012/2013 e 2013/2014 em pomar implantado no ano de 2011 com a cultivar Kinkas, sobre porta-enxerto Marubakaido com interenxerto M-9, na densidade de 1.666 plantas ha-1. Utilizou-se o delineamento experimental de blocos ao acaso, com oito repetições dos seguintes tratamentos: T1 adubação convencional; T2 irrigação + adubação convencional; T3 - irrigação + fertirrigação; e T4 - fertirrigação. Através da média das leituras diárias dos tensiômetros, e a curva de retenção de água no solo foi determinada a necessidade de irrigação e o tempo de aplicação. Em 2012, foram aplicados 27 kg ha-1 de N, e na safra seguinte 100 kg ha-1 de N e 150 kg ha-1 de K2O. A adubação foi parcelada em três aplicações para T1 e T2, e seis aplicações quinzenais para T3 e T4, no período de novembro a janeiro. Durante o período experimental foram observados vários períodos de déficit hídrico. O uso de irrigação e/ou fertirrigação não influenciou o desenvolvimento inicial de macieiras. Não houve acréscimo nos teores foliares e da polpa dos frutos para os nutrientes avaliados em resposta ao uso de irrigação para a macieira. A avaliação dos frutos demonstrou que a adubação convencional apresentou maior firmeza de polpa. Os frutos do tratamento irrigação + fertirrigação apresentaram o maior peso médio, porém a produtividade não diferiu entre os tratamentos. A fertirrigação demonstrou ser a melhor forma de aplicação de fertilizantes, mas mesmo assim é necessário aprimorar as doses e períodos de aplicação para obter máxima eficiência produtiva.(AU)

Initial growth, production, and quality of fruits of apple trees as affected by irrigation and fertirrigation / Crescimento inicial, produção e qualidade de frutos de macieiras submetidas a irrigação e fertirrigação

This study aimed to evaluate nutrient content on leaves and fruit flesh, yield and quality of fruits, as well as apple tree growth as affected by the fertilizer physical form (conventional or fertirrigation) and water addition or not via irrigation. The experiment was carried out in São Joaquim, Southern of Brazil, during the 2012/2013 and 2013/2014 growing season. The orchard was planted in 2011 with Kinkas cultivar grafted over a Marubakaido rootstock, 1.666 trees ha-1. The eight replications of each treatment were allocated in the completely randomized block design. Treatments consisted of conventional solid soil fertilization (T1), irrigation + conventional solid soil fertilization (T2), irrigation + fertirrigation (T3), and fertirrigation (T4). From the daily averages of tensiometer readings in addition to the water soil retention the irrigation needs and the application time curve were determined. In 2012, 27 kg ha-1 of N was applied; in the following season, it 100 kg ha-1 of N and 150 kg ha-1 of K2O was applied. Fertilizers were split three times on treatments T1 and T2, and six times on treatments T3 and T4, from November through January. During the experimental period it many drought periods were observed. Irrigation and fertirrigation had no effect on initial apple tree growth. Irrigation did not affect the nutrient content in leaves or fruit flesh. Fruits from the T3 (irrigation + fertirrigation) presented the highest weight. Fruit yield, however, did not differ among treatments. Fertirrigation was the best form of nutrient application to the plants, but it is necessary to determine rates and times of application to obtain the maximum productive efficiency.

O presente trabalho objetivou avaliar o desenvolvimento inicial da macieira, os aspectos nutricionais, qualidade dos frutos em função da forma de aplicação dos fertilizantes e da adição ou não de água via irrigação. O experimento foi conduzido em São Joaquim durante as estações de crescimento 2012/2013 e 2013/2014 em pomar implantado no ano de 2011 com a cultivar Kinkas, sobre porta-enxerto Marubakaido com interenxerto M-9, na densidade de 1.666 plantas ha-1. Utilizou-se o delineamento experimental de blocos ao acaso, com oito repetições dos seguintes tratamentos: T1 adubação convencional; T2 irrigação + adubação convencional; T3 - irrigação + fertirrigação; e T4 - fertirrigação. Através da média das leituras diárias dos tensiômetros, e a curva de retenção de água no solo foi determinada a necessidade de irrigação e o tempo de aplicação. Em 2012, foram aplicados 27 kg ha-1 de N, e na safra seguinte 100 kg ha-1 de N e 150 kg ha-1 de K2O. A adubação foi parcelada em três aplicações para T1 e T2, e seis aplicações quinzenais para T3 e T4, no período de novembro a janeiro. Durante o período experimental foram observados vários períodos de déficit hídrico. O uso de irrigação e/ou fertirrigação não influenciou o desenvolvimento inicial de macieiras. Não houve acréscimo nos teores foliares e da polpa dos frutos para os nutrientes avaliados em resposta ao uso de irrigação para a macieira. A avaliação dos frutos demonstrou que a adubação convencional apresentou maior firmeza de polpa. Os frutos do tratamento irrigação + fertirrigação apresentaram o maior peso médio, porém a produtividade não diferiu entre os tratamentos. A fertirrigação demonstrou ser a melhor forma de aplicação de fertilizantes, mas mesmo assim é necessário aprimorar as doses e períodos de aplicação para obter máxima eficiência produtiva.

Crop loading studies on Caricia and Eva apples grown in a mild winter area

The crop load level of an apple (Malus × domestica Borkh.) tree impacts fruit yield and quality parameters, tree vigor and biennial bearing. The optimal crop load is that which allows for consistent annual cropping and fruit quality acceptable to the market. We evaluated the effect of crop load on yield and fruit quality of two low-chill apples cv. Caricia and Eva, growing in a mild winter area. During 2010 and 2011 crop load was manually adjusted from 2 or 3 to 17 fruits cm2 of trunk cross-sectional area (TCSA). Fruit yield was positively related to crop load in both cultivars but mean fruit weight diminished as the crop load increased. For both cultivars, the production of non-commercial and small-sized fruit increased, whereas production of middle-sized fruit diminished as the fruit load increased. Shoot length was not affected by crop load in Eva whereas it was reduced in Caricia. Red skin color (RSC %) had a quadratic response to crop load in Caricia. On the other hand, the RSC % of Eva fruit was adjusted to a negative logarithmic model as an effect of crop load increment. No biennial bearing was observed in either cultivar. This research study suggests that the maximum limit of crop load for both cultivars is 7 fruits cm2 of TCSA, and the lower limit of crop load was 3 fruits cm2 of TCSA for Eva and 5 fruits cm2 of TCSA for Caricia.

Crop loading studies on Caricia and Eva apples grown in a mild winter area

The crop load level of an apple (Malus × domestica Borkh.) tree impacts fruit yield and quality parameters, tree vigor and biennial bearing. The optimal crop load is that which allows for consistent annual cropping and fruit quality acceptable to the market. We evaluated the effect of crop load on yield and fruit quality of two low-chill apples cv. Caricia and Eva, growing in a mild winter area. During 2010 and 2011 crop load was manually adjusted from 2 or 3 to 17 fruits cm2 of trunk cross-sectional area (TCSA). Fruit yield was positively related to crop load in both cultivars but mean fruit weight diminished as the crop load increased. For both cultivars, the production of non-commercial and small-sized fruit increased, whereas production of middle-sized fruit diminished as the fruit load increased. Shoot length was not affected by crop load in Eva whereas it was reduced in Caricia. Red skin color (RSC %) had a quadratic response to crop load in Caricia. On the other hand, the RSC % of Eva fruit was adjusted to a negative logarithmic model as an effect of crop load increment. No biennial bearing was observed in either cultivar. This research study suggests that the maximum limit of crop load for both cultivars is 7 fruits cm2 of TCSA, and the lower limit of crop load was 3 fruits cm2 of TCSA for Eva and 5 fruits cm2 of TCSA for Caricia.(AU)