Image-based phenotyping for identification of QTL determining fruit shape and size in American cranberry (Vaccinium macrocarponL.)

Abstract

Image-based phenotyping methodologies are powerful tools to determine quality parameters for fruit breeders and processors. The fruit size and shape of American cranberry (Vaccinium macrocarpon L.) are particularly important characteristics that determine the harvests’ processing value and potential end-use products (e.g., juice vs. sweetened dried cranberries). However, cranberry fruit size and shape attributes can be difficult and time consuming for breeders and processors to measure, especially when relying on manual measurements and visual ratings. Therefore, in this study, we implemented image-based phenotyping techniques for gathering data regarding basic cranberry fruit parameters such as length, width, length-to-width ratio, and eccentricity. Additionally, we applied a persistent homology algorithm to better characterize complex shape parameters. Using this high-throughput artificial vision approach, we characterized fruit from 351 progeny from a full-sib cranberry population over three field seasons. Using a covariate analysis to maximize the identification of well-supported quantitative trait loci (QTL), we found 252 single QTL in a 3-year period for cranberry fruit size and shape descriptors from which 20% were consistently found in all years. The present study highlights the potential for the identified QTL and the image-based methods to serve as a basis for future explorations of the genetic architecture of fruit size and shape in cranberry and other fruit crops.

Phenotypic Evaluation of a Hybrid Diploid Blueberry Population for Plant Development and Fruit Quality Traits

“…Genomic resources (mapping populations) have been recently used to map QTL for development and fruit quality traits in other berry crops, like raspberry [19], blackberry [20], cranberry [21][22][23][24] and strawberry [25]. The first genetic linkage maps for red raspberry were generated from a 'Glen Moy' × 'Latham' population [26,27].…”

“…Fruit quality traits related to fruit development, texture, color, sugar, anthocyanin and organic acid contents have been mapped in strawberry as well [25]. In cranberry, which is a member of the Vaccinium genus and is closely related to blueberry, QTL for fruit rot resistance [21,22], total anthocyanin content, titratable acidity, proanthocyanidin content, Brix and mean fruit weight [23], and fruit shape and size [24] have all been identified.…”

Pacbio Sequencing Reveals Identical Organelle Genomes between American Cranberry (Vaccinium macrocarpon Ait.) and a Wild Relative

“…In 2013, the first simple sequence repeat (SSR)-based genetic map was published, in which several quantitative trait loci (QTL) for yield-related traits and important phytochemicals were reported [21]. Subsequently, high-density genetic maps as well as more multi-trait QTL studies became available [22,23,24,25,26,27]. In addition, nuclear [28], plastid [29], and mitochondrial [30] genomes have been published recently.…”

Comprehensive analysis of the internal structure and firmness in American cranberry (Vaccinium macrocarpon Ait.) fruit

“…This may make internal structure attributes an important factor in fruit firmness. Unlike external physical attributes of the fruit such as color, size and shape, the internal structure properties have represented a challenge to measure, and until now, no method was available to measure them [23,24,25,26]. Also, the variability of internal structure characteristics across different cranberry cultivars and the contribution of internal fruit structure parameters to fruit firmness and shelf life are poorly understood [27,28,29].…”