Fernando Cesar Sala

The optimal photosynthetic photon flux density (PPFD) and seeding density (SD) combinations for microgreens production on vertical farming systems remain unclear for many species. This study aimed to determine the effects of PPFD (50, 100, 150, and 200 µmol m⁻² s⁻¹) and SD for sunflower (1275, 1700, and 2125 g m⁻²), radish (272, 340, and 408 g m⁻²), and green and red cabbage (126, 180, and 235 g m⁻²) microgreens. PPFD had no effect on the yield of sunflower, radish, or red cabbage, indicating that 50 µmol m⁻² s⁻¹ was sufficient to meet plant demands. Green cabbage yield increased ~10% at 150 µmol m⁻² s⁻¹. Increasing SD enhanced yields, with gains of up to ~22%, 49%, 52%, and 30% for sunflower, radish, green, and red cabbage, respectively (1700, 408, 235, and 180 g m⁻²). PPFD did not affect the nutrient content of sunflower, likely due to its high seed reserves. A higher SD increased anthocyanin in red cabbage but diminished its content in all other species. Our findings highlight that SD is more impactful than PPFD on determining yield, at least under low irradiance, in sunflower, radish, and red cabbage microgreens grown on indoor vertical farming systems.

Understanding the genetic diversity and population structure of Cucurbita species is essential for effective germplasm conservation and the development of improved cultivars. This study aimed to evaluate the genetic diversity, population structure, and genetic relationships among accessions of C. pepo, C. moschata and C. maxima and their interspecific hybrids (Tetsukabuto hybrid C. maxima × C. moschata). A total of 92 accessions were analyzed using 22 polymorphic simple sequence repeat (SSR) markers selected from previous studies due to their high polymorphic information content (PIC). Genetic diversity parameters were estimated, and population structure was inferred using Bayesian clustering, complemented by dendrogram and principal component analysis (PCA). All markers were successfully amplified in C. pepo, C. moschata, C. maxima, and the hybrids, with polymorphic information content (PIC) values ranging from 0.191 (CMTm232) to 0.448 (CMTm48) and average of 0.274. The AMOVA analysis showed that 50% of the total variation was attributed to differences both within and among groups. PCA revealed clear genetic differentiation among the analyzed species, with C. maxima and hybrid accessions clustering closely and exhibiting lower genetic dissimilarity. In contrast, C. pepo displayed greater genetic divergence, supporting its distinct evolutionary trajectory. According STRUCTURE analysis the accessions can be divided into four subpopulations, which are closely related to the species. PCA and dendrogram showed similar results for genetic structure of Cucurbita germplasm; C. maxima and hybrid accessions clustering closely and C. pepo as a distinct group. These findings provide valuable insights for breeding programs, germplasm management, and conservation strategies aimed at preserving genetic diversity and exploiting interspecific variation.

Mudas produzidas em maiores volumes de células podem apresentar melhor desenvolvimento em relação às produzidas em volumes menores e estarem aptas ao transplante em menor tempo quando cultivadas sob iluminação artificial. O presente trabalho teve como objetivo avaliar o desenvolvimento de mudas de alface crespa cv. BS AC0055 produzidas em quatro tipos diferentes de volumes de células das bandejas e utilizando-se duas condutividades elétricas de solução nutritiva e conduzidas sob iluminação artificial. O delineamento experimental foi inteiramente casualizado com quatro tratamentos (volumes de células de 50, 40, 20 e 10 cm³.célula-1) e quatro repetições. A condução do trabalho foi em sistema indoor localizado no laboratório presente no Departamento de Biotecnologia e Produção Vegetal e Animal (DBPVA) da universidade Federal de São Carlos - UFSCar. A condutividade elétrica das soluções nutritivas foram de 0,6 e 1,2 mS. O sistema indoor foi composto com as condições de temperatura de 23ºC, umidade relativa de 70% e intensidade luminosa de 150 µmol m-² s -¹ com fotoperíodo ajustado para 18 horas.

This study evaluated disease resistance in Cucurbita spp. using specific molecular markers. The authors evaluated 47 accessions of C. moschata and C. pepo in order to identify regions which confer resistance to Zucchini Yellow Mosaic Virus (ZYMV), Papaya Ringspot Virus Watermelon (PRSV-W), and Powdery Mildew (Erysiphe spp.). Molecular markers were amplified and analyzed according to their references. The presence of the resistance allele to ZYMV was observed in 82.6% of the C. pepo genotypes and 95.8% of the C. moschata genotypes, using SCAR and CAPS markers. In relation to resistance to PRSV-W, 62.5% of the C. pepo genotypes showed the corresponding allele. Regarding powdery mildew, 47.8% of the C. pepo genotypes were classified as resistant, whereas 62.5% of the C. moschata genotypes presented the resistance allele, based on In-Del and CAPS markers. The variations in resistance rates observed between the markers suggested a polygenic genetic control for these diseases. The results found in this study highlighted the importance of an integrative approach to marker selection for a comprehensive analysis of genetic resistance, which is essential for developing more resistant and efficient cultivars and hybrids.

This study investigated the impact of paclobutrazol (PBZ) concentrations and application protocols on ornamental quality and consumer preference. PBZ was applied at five concentrations using three different protocols: drench at transplanting, drench 30 days after transplanting, and immersion. At commercial maturity, plants were assessed based on growth parameters related to height, canopy structure, fruit and leaf characteristics, and sensory attributes. The results indicated that PBZ treatments led to darker green leaves and, in general, the drench method, regardless of time application, was more effective in modulating plant growth compared to the immersion protocol. Conversely, the sensory analysis showed a greater preference among evaluators for plants treated with PBZ at 2.5 and 5 mg L⁻¹ via drench at 30 days after transplanting (D30DAT) or through immersion (IM), even though IM was not associated with any of the ornamental quality parameters evaluated. Likewise, the application of PBZ by drench during transplanting is not recommended as the plants showed a reduced number and size of fruits, which affected the ornamental value of the plants and global preference. Therefore, PBZ applied by D30DAT at concentrations of 2.5 and 5 mg L⁻¹ produced ‘Biquinho Vermelha’ pepper plants with attractive ornamental characteristics; and thereby, should be considered an alternative method for producers of potted ornamental plants.

The growing demand for the unconventional vegetable ora-pro-nobis (Pereskia aculeata Mill.) has stimulated its cultivation. Nevertheless, the nutritional requirement and the response of the species regarding fertilization are not yet established, especially concerning yield and post-harvest quality. The aim of this work was to evaluate the effects of organic and mineral fertilization on production, nutritional composition, bioactive compounds, the antioxidant and sensory activity of ora-pro-nobis in a dense system, and successive harvests. The plants were grown i) without fertilization (control), ii) with mineral fertilization and iii) organic fertilizer: organic compost, in a randomized block design with seven replications. The production analyses occurred at 210, 270 and 330 days after seedling transplanting (DAT). The mineral composition and protein contents in the leaves were evaluated at 210 DAT and 330 DAT, and the biochemical and sensory analyses, at 330 DAT. Mineral fertilization was the most efficient in providing nutrients and increasing the productivity of ora-pro-nobis leaves. When fertilized with mineral fertilizer, ora-pro-nobis presented higher P, K, S, and fiber contents at 210 DAT, and higher values for phenolic compounds and antioxidant activity. Fertilizers did not alter the protein content and sensory characteristics of the ora-pro-nobis leaves. Mineral fertilization in ora-pro-nobis production provided production and nutritional advantages, without interfering in consumer’s preference

This work aimed to determine the effect of PBZ concentrations and application protocols on the ornamental quality and global preference of customers. PBZ was applied in five concentrations by three protocols (drench at transplanting, drench at 30 days after transplanting and immersion). At commercial maturity, the plants were evaluated for plant growth parameters related to height and canopy characteristics, fruits and leaves, in addition to sensory analysis. PBZ produced plants with darker green leaves and the drench method was more effective in modulating plant growth pa-rameters compared to immersion. Conversely, the sensory analysis showed a greater preference among evaluators for plants treated with PBZ at 2.5 and 5 mg L-1 via drench at 30 DAT or through immersion (IM), even though IM was not associated with any of the ornamental quality parameters evaluated. Likewise, the application of PBZ by drench during transplanting is not recommended as the plants showed a reduced number and size of fruits, which affected the ornamental value of the plants and global preference. Therefore, PBZ applied by drench 30DAT at concentrations of 2.5 and 5 mg L-1 produced ‘Biquinho Vermelha’ pepper plants with attractive ornamental characteristics being an alternative method for producers of potted ornamental plants.

Objetivou-se avaliar a produção, rendimento, qualidade e biometria de frutos de pimenta não pungentes cultivados em ambiente protegido por meio da poda de hastes caulinares e raleio dos frutos. Os tratamentos foram compostos por sistemas de condução das hastes (sem poda e com poda) e raleio (sem raleio e com raleio dos frutos). O delineamento experimental foi blocos casualizados com quatro repetições em esquema fatorial 2 (sem poda e com poda das hastes) x 2 (sem raleio e com raleio dos frutos). Foram avaliados os frutos de quatro plantas por parcela, totalizando oito momentos de colheita. A poda promoveu incremento na fitomassa de frutos totais e comerciais, número de frutos comerciais, comprimento (C), diâmetro (D), relação C/D, sólidos solúveis totáis, pH e acidez total titulável dos frutos de pimenta. O raleio de frutos promoveu incremento do comprimento e diâmetro médio dos frutos de pimenta. Recomenda-se a poda das hastes das plantas de pimenteira para obter maior massa média e diâmetro de frutos.

Microgreens have a high nutrient density and are beneficial to human health. Even though this class of vegetables have gaining increasing levels of attention in the last year, scientific research on the growth of microgreens in controlled environments under artificial lighting have not been thoroughly characterized. By describing the scientific outputs focused on the impacts of artificial illumination on microgreens, especially from the first two decades of the 21st century, it is therefore possible to detect advancements and research gaps in this research field. This review is divided in two parts: first, a general overview of the scientific production about microgreens; second, a systematic review of scientific studies exploring artificial lighting on the production of microgreens. The overview of scientific production on microgreens and artificial lighting across the Scopus, Web of Science, and Scielo databases, from 2000 to 2021, respectively, indicated three phases, as before 2011 no paper was found: phase 1 (2012 to 2014), six papers; phase 2 (2015 to 2018), fifteen papers; and phase 3 (2019 to 2021), forty-six papers, respectively. Mustard was the most evaluated crop under all production stages. With regard to the second part of this review, studies on artificial lighting with fluorescent lamps (high-pressure sodium light bulbs—HPS), from the supplementation to the replacement of HPS lighting with light emitting diode (LED) lamps, and plant responses with respect to light properties comprise the main works identified. Studies on the distribution of environmental factors under controlled microgreen cultivation present research gaps.

Basil (Ocimum basilicum L.) is one of the main condiments for fresh consumption and essential oil production. The aim of the present work was to assess the agronomic characterization and analyze the essential oil of 63 basil accessions. The experiment was conducted in two stages in a greenhouse using vases and a hydroponic cultivation system. Oil extraction was performed employing the Soxhlet method. There was a significant variation in the agronomic characteristics among the evaluated accessions. The estimated total contents of essential oils ranged from 0.05 to 0.40%, and the major volatile fraction was methyl-eugenol. In the present study, accessions with superior performance compared to commercial varieties were found. Accession BL11 presented agronomic characteristics suitable for cultivation in a hydroponic system due to its better plant structure and late flowering. Accession BL24 stood out for essential oil extraction, producing 17.6% of linalool and a high intensity of color and odor. Accessions BL11 and BL24 presented market potential, given their higher mass productivity and higher essential oil yield, respectively. These accessions can be made available as new varieties in addition to being used in genetic improvement programs for this species.