Model-assisted phenotyping by digital images in papaya breeding program

Abstract

Manual phenotyping for papaya Carica papaya (L) breeding purposes limits the evaluation of a great number of plants and hampers selection of superior genotypes. This study aimed to validate two methodologies for the phenotyping of morpho-agronomic plant traits using image analysis and fruit traits through image processing. In plants of the 'THB' variety and 'UENF/ Caliman-01' hybrid two images (A and B) were analyzed to estimate commercial and irregularly shaped fruits. Image A was also used in the estimation of plant height, stem diameter and the first fruit insertion height. In 'THB' fruits, largest and smallest diameters, length, and volume were estimated by using a caliper and image processing (IP). Volume was obtained by water column displacement (WCD) and by the expression of ellipsoid approximation (EA). Correlations above 0.85 between manual and image measurements were obtained for all traits. The averages of the morpho-agronomic traits, estimated by using images, were similar when compared to the averages measured manually. In addition, the errors of the proposed methodologies were low compared to manual phenotyping. Bland-Altman's approach indicated agreement between the volume estimated by WCD and EA using caliper and IP. The strong association obtained between volume and fruit weight suggests the use of regression to estimate this trait. Thus, the expectation is that image-based phenotyping can be used to expand the experiments, thereby maintaining accuracy and providing greater genetic gains in the selection of superior genotypes.

Research Article Digital phenotyping of winter squash fruits

“…In cases where it is necessary to perform fruit evaluation in a short period of time, it becomes more efficient, since it is possible to identify and acquire the images with less than one minute per fruit, allowing the images to be stored for future evaluation, or implement automated phenotyping techniques. Results are similar to those obtained by Cortes et al (2017), who reporte that phenotyping using digital images was three times faster than the manual option.…”

“…Several studies have shown the potential use of digital images to characterization, identification, classification and grading of fruits (Behera et al, 2020). There are reports of the success in passion fruit's (Sidehabi et al, 2018), persimmon (Maeda et al, 2018), papaya (Cortes et al, 2017), tomatoes (Zaborowicz et al, 2017), orange (Rashidi et al, 2009), melon (Khojastehnazhand et al, 2009), watermelon (Koc, 2007), etc. However, digital imaging techniques to characterize winter squash germplasm have not been reported.…”

Combining ability of recombined F4 papaya lines: a strategy to select hybrid combination

“…We used an image-based phenotyping methodology, validated and described by Cortes et al (2017) to phenotyping papaya plants, to measure the following traits: plant height -PH (cm), measured from the ground base to the insertion of the last pair of leaves; stem diameter -SD (cm), measured at 20 cm from the ground; first-fruit insertion height -FFIH (cm), measured from the ground base to the first fruit insertion into the stem; number of marketable fruits -NMF, determined by counting fruits with commercial traits; number of deformed fruits -NDF, determined by the count of carpeloid and pentandric fruits in each plant; number of fruitless nodes -NFN, by counting fruitless nodes in each plant; average fruit weight -FW (g), determined by weighing five fruits on an digital analytical scale; and yield -YLD (kg per plant).…”

Quantification of floral abnormalities in a population generated from sexual polymorphism aiming at recurrent selection in papaya

“…The traits were evaluated by the digital-phenotypic methodology, as validated and described by Cortes et al (2017a), using a Sony DSCHX 300 digital camera. Each plant was photographed in two different positions, one of them perpendicular to the plant, considering the axis of the row, and the other one considering the opposite side of the same plant used in Fig.…”