ABSTRACT Traditional germination tests which assess seed quality are costly and time-consuming, mainly when performed on a large scale. In this study, we assessed the efficiency of X-ray imaging analyses in predicting the physiological quality of tomato seeds. A convolutional neural network (CNN) called mask region convolutional neural network (MaskRCNN) was also tested for its precision in adequately classifying tomato seeds into four seed quality categories. For this purpose, X-ray images were taken of seeds of 49 tomato genotypes (46 Solanum pennellii introgression lines) from two different growing seasons. Four replicates of 25 seeds for each genotype were analyzed. These seeds were further assessed for germination and seedling vigor-related traits in two independent trials. Correlation analysis revealed significant linear association between germination and image-based variables. Most genotypes differed in terms of germination and seed development performance considering the two independent trials, except LA 4046, LA 4043, and LA4047, which showed similar behavior. Our findings point out that seeds with low opacity and percentage of damaged seed tissue and high values for living tissue opacity have greater physiological quality. In short, our work confirms the reliability of X-ray imaging and deep learning methodologies in predicting the physiological quality of tomato seeds.

ABSTRACT. To be considered drought-tolerant, a tomato cultivar is required to present some level of tolerance at all developmental stages of plant growth. Since drought tolerance is a stage-specific phenomenon, genotype assessment must be performed separately at all developmental stages. In this study, we used a multi-trait index based on factor analysis and genotype-ideotype distance (FAI-BLUP index) to properly rank 49 tomato genotypes according to their tolerance to drought stress conditions at germination and seedling stages. Seeds of 47 introgression lines, which cultivar M82 is considered drought-sensitive, and the Solanum pennellii wild accession LA 716, which is considered drought-tolerant, were subjected to a control condition, where seeds were soaked in distilled water, and a drought condition, where seeds were soaked in a polyethylene glycol (PEG) solution (-0.3 MPa). Drought stress, induced by PEG, had a significant impact on all nine germination and growth performance-related traits; there was a reduction in shoot length (SL), total length (TL), initial germination percentage (IGP), final germination percentage (FGP), germination velocity index (GVI), and germination rate (GR). In contrast, the root-to-shoot ratio (R/S) and time to reach 50% germination (T50) increased under drought stress. Root length (RL) was less affected by drought, and in some genotypes, it was even increased. As expected, LA 716 ranked closest to the drought tolerance ideotype. IL 1-4-18, IL 2-3, IL 1-2, IL 9-2, and IL 10-1 were the most drought-tolerant at the germination stage. These results will serve as guidance for breeders who are aiming at developing drought-resistant tomato cultivars.

RESUMEN El umbú (Spondias tuberosa Arruda) es un árbol frutal adaptado a la región semiárida brasileña y constituye una fuente de ingresos importante para muchas familias en Brasil. Debido a esto, se deben estudiar métodos sostenibles de conservación de la fruta después de la cosecha. El objetivo de este estudio fue analizar la influencia de la biopelícula de almidón de yuca para la conservación poscosecha del umbú. El diseño experimental fue completamente al azar en un arreglo factorial 2x5 con seis repeticiones. Los dos tratamientos, recubrimiento de almidón de yuca al 1% y sin recubrimiento, se evaluaron durante cinco períodos (0, 3, 6, 9 y 12 d de almacenamiento). Se midieron la pérdida de peso fresco (PPF), la firmeza de la fruta (FIR), el pH, los sólidos solubles totales (SST), la acidez total titulable (AT), la relación SST/AT, el color: la luminosidad (L*), el ángulo de tonalidad (T*) y la cromaticidad (C*). El recubrimiento de los frutos con la biopelícula a base de almidón de yuca mejoró el PPF, el pH y los SST. La AT, la relación SST/AT y la L* no fueron influenciadas por el uso o ausencia del recubrimiento. El uso de almidón de yuca al 1% asegura una mejor calidad poscosecha del umbú y prolonga su vida poscosecha.

ABSTRACT The umbu (Spondias tuberosa Arruda) is a fruit tree adapted to the Brazilian semiarid region and constitutes an important source of income for many families in Brazil. Due to this, sustainable methods of fruit postharvest conservation should be studied. The objective of this study was to analyze the influence of cassava starch-based biofilm coatings for the postharvest conservation of umbu. The experimental design was completely randomized in a 2x5 factorial arrangement with six replicates. The two treatments, 1% cassava starch coating and no coating, were evaluated during five periods (0, 3, 6, 9, and 12 d of storage). Fresh weight loss (WL), fruit firmness (FIR), pH, total soluble solids (TSS), total titratable acidity (TA), TSS/ TA ratio, external color: luminosity (L*), hue angle (H*), and chromaticity (C*) were measured. The coating of fruits with cassava starch-based biofilm improved WL, pH, and TSS. The variables TA, TSS/TA ratio, and L* were not influenced by the use or absence of the cassava starch biofilm coating. The use of 1% cassava starch to coat the fruits ensures better postharvest quality of the umbu and extends its postharvest life.

RESUMO Hancornia speciosa Gomes é uma das espécies frutíferas nativas mais frequentes no Cerrado. Estudos sobre a variabilidade genética de caracteres quantitativos para essa espécie são escassos e a identificação de acessos com as melhores características agronômicas pode subsidiar estratégias de programas de conservação e melhoramento genético. Objetivou-se estimar a diversidade genética de acessos da coleção de germoplasma de H. speciosa da Universidade Federal de Goiás e classificá-los com base em um índice de seleção combinando onze características agronômicas. Foram avaliados 192 acessos individuais de 57 progênies, de 29 populações naturais. Os dados foram submetidos a análise multivariada e os indivíduos e progênies avaliados pelo índice de seleção FAI-BLUP. A análise de agrupamento de Tocher permitiu agrupar as progênies em dez agrupamentos divergentes e os indivíduos em 18 agrupamentos divergentes. A seleção simultânea de caracteres com base no índice FAI-BLUP pode ser recomendada, mantendo-se a variabilidade potencial na população resultante da recombinação. A seleção individual mostrou-se mais eficaz do que a seleção baseada em médias de progênies, por explorar a variação genética entre e dentro das progênies.

ABSTRACT Hancornia speciosa Gomes is one of the native fruit species most frequent in the Brazilian Savanna. Studies on the genetic variability of quantitative traits for this species are scarce and the identification of accessions with the best agronomic traits may support strategies for conservation and breeding programs. This study aimed to estimate the genetic diversity of accessions from the H. speciosa germplasm collection of the Universidade Federal de Goiás (Goiânia, Goiás state, Brazil) and rank them based on a selection index combining eleven agronomic traits. A total of 192 individual accessions from 57 progenies, from 29 natural populations, were evaluated. The data were subjected to multivariate analysis and the individuals and progenies evaluated using the FAI-BLUP selection index. The Tocher cluster analysis allowed grouping the progenies into ten divergent clusters and the individuals into 18 divergent clusters. The simultaneous selection of traits based on the FAI-BLUP index may be recommended while maintaining the potential variability in the population resulting from the recombination. The individual selection proved to be more effective than the selection based on progenies means, because it exploits the genetic variation among and within progenies.