Fruit quality is a key criterion used to select new cultivars in kiwifruit breeding programs. The... more Fruit quality is a key criterion used to select new cultivars in kiwifruit breeding programs. The aim of this research was to identify quantitative trait loci (QTLs) that control traits related to fruit quality in an F1 population derived from the cross of 'C8' (female) and 'A54.19' (male) diploid kiwifruit. A small female progeny was evaluated over 3 years for several traits: fruit weight, absorbance of chlorophyll (IAD) values of the skin and flesh, flesh firmness, soluble solids content (SSC), titratable acidity (TA), pH, dry matter (DM) content and ripening time (RT). Single or multiple QTL mapping models were applied separately for each year and all years combined. As a result, a total of 24 QTLs were detected on 12 different linkage groups (LGs). Some QTLs, such as flesh firmness, skin and flesh chlorophyll absorbance, are reported for the first time in kiwifruit. However, QTLs were not consistent among years, and were rarely identified in both parents in corresponding LGs. These results were expected, because of the limited size of the progeny. This work was the first attempt to identify genomic regions that control fruit-quality traits in the mapping cross population. Extension of the cross population to about 400 female individuals has been undertaken, and this will guarantee a more reliable and robust identification of QTLs related to fruit quality in future analyses.
Kiwifruit breeding still largely relies on phenotypic observation of cross progeny grown in the f... more Kiwifruit breeding still largely relies on phenotypic observation of cross progeny grown in the field to fruiting maturity, without any selection prior to the juvenility being overcome. Developing markers for the selection of traits of interest would greatly help breeders to rapidly screen breeding populations. With the aim of mapping several traits of interest in kiwifruit, a F1 population of diploid (2n=58) Actinidia chinensis was produced by combining parents with contrasting phenotypic traits. Ninety-four individuals were preliminarily analyzed to obtain a saturated genetic map based on 167 SSRs from the literature and 12,586 segregating restriction-site-associated DNA (RAD) loci obtained through an approach known as genotyping-by-sequencing (GBS) based on haplotype calling of SNP markers identified by a modified double digest restriction-associated DNA sequencing (ddRADseq) protocol as proposed by Peterson et al. (2012). To improve the accuracy of genotype calling, restriction-site-associated reads were aligned to the scaffolds of the recently published kiwifruit genome (Huang et al. 2013). This strategy provided genetic anchoring to 557 Mbp (90 %) of the assembly, helping also to anchor some 120 unmapped Mbp and to identify some mis-joined scaffolds. The analysis of the region controlling the dioecy in kiwifruit, spanning 16 scaffolds in the pseudomolecule 25 of the genome assembly (approximately 4.9 Mbp), with RAD markers that co-segregated with the gender determinant, allowed to sort out markers suitable for marker-assisted selection for the gender in the mapping population with successful extension to further controlled crosses having parents at different ploidy level and belonging to the A. chinensis/Actinidia deliciosa complex.
ing. For that, the mean, maximum, and minimum temperatures were used to describe weather during t... more ing. For that, the mean, maximum, and minimum temperatures were used to describe weather during the autumns, winters, and early springs, for to be related with yield performance. Crop load-adjusted yield efficiency ranged between 10.1 and 6.8 kg m-2 PAR i , and fruit weight was found to be 134.4 g and 189.5 g among zones. The results showed that the crop load-adjusted yield and fruit size depended primarily on the maximum temperature during winter, and secondly, on season length (from bloom to harvest), with colder areas yielding better performance.
There is a need to develop alternative harvest indexes for black skinned plums. The aim of this r... more There is a need to develop alternative harvest indexes for black skinned plums. The aim of this research was to analyze and compare the most commonly used indexes for deciding the harvest date for Japanese plum, and evaluate the effectiveness of new approaches for studying maturation. The ripening process was monitored on-tree and during postharvest in a non-destructive way, through
Annual accumulation of starch is affected by carbon reserves stored in the organs during the grow... more Annual accumulation of starch is affected by carbon reserves stored in the organs during the growing season and is controlled mainly by sink strength gradients within the tree. However, unfavorable environmental conditions (e.g., hail events) or application of management practices (e.g., defoliation to enhance overcolor in bicolor apple) could influence the allocation of storage carbohydrates. This preliminary research was conducted to determine the effects of early defoliation on the dry matter, starch, and soluble carbohydrate dynamics in woody organs, roots, and mixed buds classified by age and two levels of crop-load for one growing season in ‘Abbé Fétel’ pear trees (Oct. 2012 to mid-Jan. 2013 in the northern hemisphere). Regardless of the organs evaluated (woody organs, roots, and mixed buds), an increase of soluble carbohydrate concentration was observed in these organs in the period between after harvest (October) and January (dormancy period). Among all organs, woody short-o...
The aims of this study were to characterize the softening rate of the flesh and some physiologica... more The aims of this study were to characterize the softening rate of the flesh and some physiological parameters of three peach cultivars during the last phase of on-tree development. During two consecutive seasons, labeled fruits were nondestructively monitored on-tree, from the stone-hardening phase up to harvest. The absorbance index of the skin (IAD) follows a segmented, nonlinear regression. Beyond the intersection point of the two segments of the regression, the IAD decreased linearly at a higher rate 10 to 15 day before harvest. The most dramatic change of the IAD coincided with the “color break” of the skin. The IAD and the flesh softening were similar in ‘Andes Du-1’ and ‘Loadel’, while there was no difference in the growth rate of ‘Bowen’ and ‘Loadel’. ‘Andes Du-1’ and ‘Bowen’ showed the same growth rate in the upper and the lower sections of the canopy. The fruit at the upper section showed a mass of 30 to 50 g greater than the fruit at the lower section. In addition, no sig...
Several orchard management practices and postharvest strategies have been adopted to increase pro... more Several orchard management practices and postharvest strategies have been adopted to increase productivity and maintain fruit quality. Growth regulator sprays have been widely used to improve the size of stone fruits. The aim of this study was to evaluate the effect of sprays of different combinations of prohexadione-calcium (P-Ca) and naphthalene acetic acid (NAA) on 'Castlebrite' apricot trees, particularly on tree yield and maintain fruit quality after a cold storage period. The treatments were: T0 = control; T1 = P-Ca spray with 10 cm-long shoots, spray with P-Ca 10 d after, and spray with P-Ca 20 d after; T2 = NAA spray with 10 cm-long shoots, spray with P-Ca and NAA 10 d after; T3 = NAA spray with 10 cm-long shoots; T4 = NAA spray with 10 cm-long shoots, spray with NAA 10 d later. The har-vested fruit was stored in cold storage chamber for 0, 20 and 40 d, and then evaluated the quality attributes. Fruit quality was evaluated instrumentally and by sensory analysis condu...
Durante la temporada 2004-2005 se realizó un ensayo en manzanos, variedad Royal Gala, de 10 años ... more Durante la temporada 2004-2005 se realizó un ensayo en manzanos, variedad Royal Gala, de 10 años de edad, injertados sobre patrón MM106, plantados a una distancia de 5 x 3 m, en el fundo `El Boldar´, localidad de Corcolén, VI Región. El objetivo fue establecer una relación que explicase la productividad y el tamaño de fruto, como función de la interceptación de radiación solar y la carga frutal. Para esto, se seleccionaron 32 árboles, los cuales fueron separados de acuerdo a su área sección transversal de tronco (ASTT), medida a inicios del ensayo, en dos grupos: árboles de tamaño grande y de tamaño chico. La fracción de radiación solar interceptada por los dos grupos de árboles se midió cada 20 días durante la temporada, desde el 1 de octubre hasta cosecha, con un sensor Accupar LP- 80, en tres momentos del día: a medio día solar (MDS), 2 y 4 horas antes o después del MDS. En la cosecha, se evaluó la producción total, número de frutos y peso medio de fruto cosechados por árbol. Par...
Several orchard management practices and postharvest strategies have been adopted to increase pro... more Several orchard management practices and postharvest strategies have been adopted to increase productivity and maintain fruit quality. Growth regulator sprays have been widely used to improve the size of stone fruits. The aim of this study was to evaluate the effect of sprays of different combinations of prohexadionecalcium (P-Ca) and naphthalene acetic acid (NAA) on 'Castlebrite' apricot trees, particularly on tree yield and maintain fruit quality after a cold storage period. The treatments were: T0 = control; T1 = P-Ca spray with 10 cm-long shoots, spray with P-Ca 10 d after, and spray with P-Ca 20 d after; T2 = NAA spray with 10 cm-long shoots, spray with P-Ca and NAA 10 d after; T3 = NAA spray with 10 cm-long shoots; T4 = NAA spray with 10 cm-long shoots, spray with NAA 10 d later. The harvested fruit was stored in cold storage chamber for 0, 20 and 40 d, and then evaluated the quality attributes.
Fruit quality is a key criterion used to select new cultivars in kiwifruit breeding programs. The... more Fruit quality is a key criterion used to select new cultivars in kiwifruit breeding programs. The aim of this research was to identify quantitative trait loci (QTLs) that control traits related to fruit quality in an F1 population derived from the cross of 'C8' (female) and 'A54.19' (male) diploid kiwifruit. A small female progeny was evaluated over 3 years for several traits: fruit weight, absorbance of chlorophyll (IAD) values of the skin and flesh, flesh firmness, soluble solids content (SSC), titratable acidity (TA), pH, dry matter (DM) content and ripening time (RT). Single or multiple QTL mapping models were applied separately for each year and all years combined. As a result, a total of 24 QTLs were detected on 12 different linkage groups (LGs). Some QTLs, such as flesh firmness, skin and flesh chlorophyll absorbance, are reported for the first time in kiwifruit. However, QTLs were not consistent among years, and were rarely identified in both parents in corresponding LGs. These results were expected, because of the limited size of the progeny. This work was the first attempt to identify genomic regions that control fruit-quality traits in the mapping cross population. Extension of the cross population to about 400 female individuals has been undertaken, and this will guarantee a more reliable and robust identification of QTLs related to fruit quality in future analyses.
Kiwifruit breeding still largely relies on phenotypic observation of cross progeny grown in the f... more Kiwifruit breeding still largely relies on phenotypic observation of cross progeny grown in the field to fruiting maturity, without any selection prior to the juvenility being overcome. Developing markers for the selection of traits of interest would greatly help breeders to rapidly screen breeding populations. With the aim of mapping several traits of interest in kiwifruit, a F1 population of diploid (2n=58) Actinidia chinensis was produced by combining parents with contrasting phenotypic traits. Ninety-four individuals were preliminarily analyzed to obtain a saturated genetic map based on 167 SSRs from the literature and 12,586 segregating restriction-site-associated DNA (RAD) loci obtained through an approach known as genotyping-by-sequencing (GBS) based on haplotype calling of SNP markers identified by a modified double digest restriction-associated DNA sequencing (ddRADseq) protocol as proposed by Peterson et al. (2012). To improve the accuracy of genotype calling, restriction-site-associated reads were aligned to the scaffolds of the recently published kiwifruit genome (Huang et al. 2013). This strategy provided genetic anchoring to 557 Mbp (90 %) of the assembly, helping also to anchor some 120 unmapped Mbp and to identify some mis-joined scaffolds. The analysis of the region controlling the dioecy in kiwifruit, spanning 16 scaffolds in the pseudomolecule 25 of the genome assembly (approximately 4.9 Mbp), with RAD markers that co-segregated with the gender determinant, allowed to sort out markers suitable for marker-assisted selection for the gender in the mapping population with successful extension to further controlled crosses having parents at different ploidy level and belonging to the A. chinensis/Actinidia deliciosa complex.
ing. For that, the mean, maximum, and minimum temperatures were used to describe weather during t... more ing. For that, the mean, maximum, and minimum temperatures were used to describe weather during the autumns, winters, and early springs, for to be related with yield performance. Crop load-adjusted yield efficiency ranged between 10.1 and 6.8 kg m-2 PAR i , and fruit weight was found to be 134.4 g and 189.5 g among zones. The results showed that the crop load-adjusted yield and fruit size depended primarily on the maximum temperature during winter, and secondly, on season length (from bloom to harvest), with colder areas yielding better performance.
There is a need to develop alternative harvest indexes for black skinned plums. The aim of this r... more There is a need to develop alternative harvest indexes for black skinned plums. The aim of this research was to analyze and compare the most commonly used indexes for deciding the harvest date for Japanese plum, and evaluate the effectiveness of new approaches for studying maturation. The ripening process was monitored on-tree and during postharvest in a non-destructive way, through
Annual accumulation of starch is affected by carbon reserves stored in the organs during the grow... more Annual accumulation of starch is affected by carbon reserves stored in the organs during the growing season and is controlled mainly by sink strength gradients within the tree. However, unfavorable environmental conditions (e.g., hail events) or application of management practices (e.g., defoliation to enhance overcolor in bicolor apple) could influence the allocation of storage carbohydrates. This preliminary research was conducted to determine the effects of early defoliation on the dry matter, starch, and soluble carbohydrate dynamics in woody organs, roots, and mixed buds classified by age and two levels of crop-load for one growing season in ‘Abbé Fétel’ pear trees (Oct. 2012 to mid-Jan. 2013 in the northern hemisphere). Regardless of the organs evaluated (woody organs, roots, and mixed buds), an increase of soluble carbohydrate concentration was observed in these organs in the period between after harvest (October) and January (dormancy period). Among all organs, woody short-o...
The aims of this study were to characterize the softening rate of the flesh and some physiologica... more The aims of this study were to characterize the softening rate of the flesh and some physiological parameters of three peach cultivars during the last phase of on-tree development. During two consecutive seasons, labeled fruits were nondestructively monitored on-tree, from the stone-hardening phase up to harvest. The absorbance index of the skin (IAD) follows a segmented, nonlinear regression. Beyond the intersection point of the two segments of the regression, the IAD decreased linearly at a higher rate 10 to 15 day before harvest. The most dramatic change of the IAD coincided with the “color break” of the skin. The IAD and the flesh softening were similar in ‘Andes Du-1’ and ‘Loadel’, while there was no difference in the growth rate of ‘Bowen’ and ‘Loadel’. ‘Andes Du-1’ and ‘Bowen’ showed the same growth rate in the upper and the lower sections of the canopy. The fruit at the upper section showed a mass of 30 to 50 g greater than the fruit at the lower section. In addition, no sig...
Several orchard management practices and postharvest strategies have been adopted to increase pro... more Several orchard management practices and postharvest strategies have been adopted to increase productivity and maintain fruit quality. Growth regulator sprays have been widely used to improve the size of stone fruits. The aim of this study was to evaluate the effect of sprays of different combinations of prohexadione-calcium (P-Ca) and naphthalene acetic acid (NAA) on 'Castlebrite' apricot trees, particularly on tree yield and maintain fruit quality after a cold storage period. The treatments were: T0 = control; T1 = P-Ca spray with 10 cm-long shoots, spray with P-Ca 10 d after, and spray with P-Ca 20 d after; T2 = NAA spray with 10 cm-long shoots, spray with P-Ca and NAA 10 d after; T3 = NAA spray with 10 cm-long shoots; T4 = NAA spray with 10 cm-long shoots, spray with NAA 10 d later. The har-vested fruit was stored in cold storage chamber for 0, 20 and 40 d, and then evaluated the quality attributes. Fruit quality was evaluated instrumentally and by sensory analysis condu...
Durante la temporada 2004-2005 se realizó un ensayo en manzanos, variedad Royal Gala, de 10 años ... more Durante la temporada 2004-2005 se realizó un ensayo en manzanos, variedad Royal Gala, de 10 años de edad, injertados sobre patrón MM106, plantados a una distancia de 5 x 3 m, en el fundo `El Boldar´, localidad de Corcolén, VI Región. El objetivo fue establecer una relación que explicase la productividad y el tamaño de fruto, como función de la interceptación de radiación solar y la carga frutal. Para esto, se seleccionaron 32 árboles, los cuales fueron separados de acuerdo a su área sección transversal de tronco (ASTT), medida a inicios del ensayo, en dos grupos: árboles de tamaño grande y de tamaño chico. La fracción de radiación solar interceptada por los dos grupos de árboles se midió cada 20 días durante la temporada, desde el 1 de octubre hasta cosecha, con un sensor Accupar LP- 80, en tres momentos del día: a medio día solar (MDS), 2 y 4 horas antes o después del MDS. En la cosecha, se evaluó la producción total, número de frutos y peso medio de fruto cosechados por árbol. Par...
Several orchard management practices and postharvest strategies have been adopted to increase pro... more Several orchard management practices and postharvest strategies have been adopted to increase productivity and maintain fruit quality. Growth regulator sprays have been widely used to improve the size of stone fruits. The aim of this study was to evaluate the effect of sprays of different combinations of prohexadionecalcium (P-Ca) and naphthalene acetic acid (NAA) on 'Castlebrite' apricot trees, particularly on tree yield and maintain fruit quality after a cold storage period. The treatments were: T0 = control; T1 = P-Ca spray with 10 cm-long shoots, spray with P-Ca 10 d after, and spray with P-Ca 20 d after; T2 = NAA spray with 10 cm-long shoots, spray with P-Ca and NAA 10 d after; T3 = NAA spray with 10 cm-long shoots; T4 = NAA spray with 10 cm-long shoots, spray with NAA 10 d later. The harvested fruit was stored in cold storage chamber for 0, 20 and 40 d, and then evaluated the quality attributes.
Uploads
Papers by karen Mesa