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When obtaining new cultivars or monitoring the nutritional composition of lettuce, new techniques are necessary given the high cost and time required to conduct laboratory analyses of plant composition by conventional methods. The objective of this study was to evaluate different vegetation indices for the estimation of anthocyanin, chlorophyll, and carotenoids in mini-lettuce genotypes with different leaf colors and different typologies from red, green, and blue (RGB) images. The contents of pigments were evaluated in 15 lettuce genotypes, in addition to the soil plant analysis development (SPAD) index and vegetation indices in the visible range. The variability among genotypes was confirmed by the Scott-Knott test (p < 0.05) and multivariate analysis. Linear regressions were obtained between the green leaf index (GLI) and leaf pigments. GLI was a good predictor for estimating the contents of anthocyanin (r = −0.83; r2 = 0.75), carotenoid (r = −0.59; r2 = 0.43), chlorophyll a (r = −0.69; r2 = 0.48), chlorophyll b (r = −0.62; r2 = 0.39), and total chlorophyll (r = −0.77; r2 = 0.65) in red and green mini-lettuce. The high-performance phenotyping technique can be used to evaluate leaf pigments in breeding programs, as well as in crops for monitoring biofortification levels in lettuce. [ABSTRACT FROM AUTHOR]

Spectral characterization of coffee cultivars after pruning may help predict the crop's diverse phytotechnical behaviors. Therefore, this study aimed to differentiate coffee genotypes based on leaf reflectance following pruning and to develop models capable of estimating the agronomic parameters of vegetative growth. This study included eight coffee cultivars. The biochemical and leaf structure parameters were quantified for the spectral characterization of each genotype and adopted as the basis for the application of vegetation indices and to generate models that can estimate agronomic parameters after pruning. The cultivar Topázio MG-1190 proved to be the most efficient at absorbing electromagnetic radiation in the blue (220–510 nm), green (520–590 nm), and red (690–730 nm) spectral ranges among all other cultivars after pruning. The regression models could estimate the following vegetative growth parameters of the coffee cultivars: height using the normalized difference water index (root mean square error (RMSE) = 5.78%), crown diameter and plagiotropic branch length using the enhanced vegetation index (RMSE = 10.21% and 12.69%, respectively), the number of nodes using the chlorophyll b index (RMSE = 14.47%), chlorophyll a content using the photochemical reflectance index (RMSE = 2.39%), and leaf water potential using the leaf water vegetation index-1 (40.72%). The hyperspectral characterization of coffee cultivars with respect to the phytotechnical development of the genotypes after pruning was successfully accomplished. This tool can assist coffee growers to enhance their competitiveness and productivity through the development of management strategies such as the early detection of plant growth issues. [ABSTRACT FROM AUTHOR]

Increased productivity, nutritional quality, and pest resistance have been primary breeding goals. However, managing such increases in a genotype is challenging. In this context, gene introgression using dwarf plants is an alternative; however, there are no dwarf Santa Cruz tomato varieties for direct use in breeding programs. Therefore, the objective of this study was to improve fruit quality and pest resistance through successive backcrossing of dwarf Santa Cruz tomato populations with agronomic potential. Six and 13 dwarf tomato populations obtained from the first and second backcrossing, respectively, the donor parent, and the commercial cultivar 'Santa Clara' as the check, totalling 21 treatments, were evaluated. Univariate analysis and computational intelligence were used to evaluate the best genotypes. All agronomic variables showed significant and progressive increases after the first and second backcrossing. The highlighted BC2 populations were Sci#16.1-2, Sci#25.1,1-2, Sci#25.1,2-2, Sci#3.1,1-2, Sci#3.1,2-2, Sci#8.3,1-2, and Sci#8.3,2-2, with significant increases in mean fruit weight, pulp thickness, fruit length and diameter, and acyl sugar content. The selected BC2 populations can be used as male parents to obtain normal hybrids to achieve increased productivity, nutritional quality, and a broader spectrum of pest resistance owing to the presence of acyl sugars in the leaflets. [ABSTRACT FROM AUTHOR]

Conventional methodology in the field for the sampling of coffee leaf rust, caused by Hemileia vastatrix, has proven to be impractical. This paper proposes a method for the early detection of this disease, which is the most significant pathogen of coffee plants worldwide, using multispectral images acquired using a Mapir Survey3W camera and an unmanned aerial vehicle (UAV). For this purpose, 160 coffee seedlings of the coffee cultivar 'Mundo Novo' were inoculated with urediniospores of H. vastatrix and compared with 160 control (non-inoculated) seedlings to determine the most favorable interval for distinguishing healthy and infected plants. The 320 seedlings were placed on a dark surface to perform the imaging flights. In vitro analyses of the physiological parameters of 20 specimens were then performed for each condition (inoculated/non-inoculated) to obtain the hyperspectral curves, and this process was repeated three times at 15, 30, and 45 days after inoculation (DAI). Based on the simulated hyperspectral curves, a discrepancy between the red and near-infrared (NIR) bands was identified at 15 DAI, with the inoculated plants showing greater absorption in the red band and a greater spectral response in the NIR band. Thus, multispectral images were able to distinguish H. vastatrix infection in coffee seedlings at an asymptomatic stage (15 DAI) using a support vector machines (SVM) algorithm. Detection accuracy was 80% and the Kappa index of agreement was moderate (0.6). The early detection of this pathogen in the field using low-cost technology can be an important tool for the monitoring of coffee leaf rust and, consequently, a more sustainable management of the pathogen, causing farmers to make applications of chemical fungicides only when necessary. [ABSTRACT FROM AUTHOR]

• A new biosensor to ovarium cancer was developed using modified screen-printed carbon electrode. • The immunosensor was able of detect until 1.45 U mL−1 of oncomarker CA125. • The immunosensor was successfully applied in biological sample using DPV, SPR and AFM. • The immunosensor was able of discriminate negative and positive serum. This paper reports the construction of a new electrochemical immunosensor for detection of oncomarker CA125 for diagnosis and monitoring of ovarian cancer. The platform was developed using screen-printed carbon electrodes modified with poly(3-hydroxyphenylacetic acid) and anti-CA125 as probe for evaluate the biomolecular interactions (anti-CA125:CA125) onto the solid surface. Current response of the system has a linear relationship of anti-CA125 concentration in the range of 5 to 80 U mL−1 with a limit of detection of 1.45 U mL−1, discriminating between negative and positive serum. The immunosensor was successfully applied to determination of CA-125 in real biological samples using differential pulse voltammetry (DPV), surface plasmon resonance (SPR) and atomic force microscopy (AFM). The results showed the developed immunosensor is versatile, easily integrated to the point of care applications, being an interesting platform to ovarian cancer diagnose in complex samples. [ABSTRACT FROM AUTHOR]

• High performance phenotyping enables non-destructive analysis of plants. • Image phenotyping assists indirect selection of carotenoid-rich lettuces. • Image phenotype has high correlation with the carotenoid content in lettuce. • Phenotyping by image allows to identify genetic backgrounds in germplasm. • Image phenotyping determines the level of biofortification in producing regions. Developing biofortified foods is a goal of genetic breeding programs. However, analysis costs and the time required for leaf sampling in the field are hindrances to this process. The objectives of this study were to evaluate the genetic diversity in red leaf lettuce germplasm and to evaluate the use of image phenotyping for the identification of carotenoid-rich genotypes. The experiment was carried out in 2018 at the Vegetable Experiment Station of the Federal University of Uberlândia-Monte Carmelo campus. Thirty inbred lines of red leaf lettuce were evaluated. All inbred lines resulted from the hybridization of the Belíssima and Uberlândia 10000 cultivars and six successive selfings, carried out from 2013 to 2017. The genealogical method or pedigree is a working procedure used by plant breeders working with plant species whose reproductive system is autogamous and presenting cleistogamy. This method was used to obtain the treatments of the experiment. The cultivar Belíssima (red lettuce) was used as a control, totaling 31 treatments. A conventional method and an aerial image phenotyping using Phantom 4 unmanned aerial vehicle (UAV) were used to evaluate six different agronomic characteristics and carotenoid levels of each treatment. The results showed substantial genetic diversity within the germplasm bank. Furthermore, high performance image phenotyping was highly correlated with the traditional methodology (r = -0.8732, coefficient of determination = 76.25%) and can therefore be considered an alternative for identifying different genetic backgrounds within a germplasm bank. Unmanned aerial vehicle (UAV) might also be used to monitor biofortification levels in crops. [ABSTRACT FROM AUTHOR]

• β-carotene content was stable in sweet potato under different site conditions. • Dry matter and sugar content do not explain sweet potato eating preference. • Clay soil can affect β-carotene concentration. • Altitude does not impact sugar and β-carotene concentration. Blind starvation caused by micronutrient deficiency is a major issue in many countries. The use of crops with higher micronutrient content, also known as biofortification, is one of different strategies to overcome this issue. Brazil has been using this approach within the last years but in order to expand this program it is necessary to characterize and develop new cultivars that meet consumer's demands. Three orange fleshed sweet potato genotypes were evaluated in eight different site locations with different soil, management and altitude conditions. Total soluble sugars, carotenoids, dry matter and sensory evaluation were performed. β-carotene was the predominant carotenoid in the three sweet potato genotypes. This provitamin A compound was consistently higher than 70 μg g−1 in all genotypes, independent of site locations. CIP BRS Nuti cultivar presented significant higher dry matter and sucrose content in comparison with Beauregard and Clone 11. These last genotypes presented higher fructose and glucose content than CIP BRS Nuti. Acceptance evaluation demonstrated that despite having different organoleptic characteristics, CIP BRS Nuti and Beauregard were preferred by tasters. This finding is relevant since CIP BRS Nuti is a new commercial sweetpotato cultivar that will be part of the portfolio of biofortified cultivars in Brazil. [ABSTRACT FROM AUTHOR]