Fernando Angelo Piotto

Potato germplasm developed under tropical conditions may contain diversity for breeding, but the Brazilian materials remain poorly characterized. We evaluated 449 tetraploid potato clones, most from Brazilian breeding programs, with 12,595 SNPs. Dosage-aware analyses and STRUCTURE supported four breeding-related clusters. Genetic differentiation between Brazilian and foreign populations was low (Φ _ST = 0.04), indicating extensive use of external germplasm in Brazilian breeding. In contrast, differentiation among the genetic clusters was moderate (Φ _ST = 0.22), suggesting preferable restricted parental use in their pipelines. Heterozygosity and inbreeding estimates depended strongly on genotype encoding. Tajima’s D was positive (4.46), and suggested selection favoring increased heterozygosity. Three genome scans identified 92 shared candidate outlier SNPs within broad LD-based windows. The functional annotations generated hypotheses related to stress responses for further studies to be functionally validated. The results provide insights at a panel-level baseline for germplasm management and candidate prioritization in Brazilian potato breeding.

Potato (Solanum tuberosum L.) is a globally important staple crop whose productivity is increasingly threatened by concurrent abiotic and biotic stresses under climate change. Transcription factors of the WRKY family have emerged as central regulatory hubs coordinating stress-responsive multiple networks and specialized metabolism. This article highlights current advances in WRKY research in potato, with a particular focus on functional genetic manipulation approaches aimed at enhancing multi-stress resilience. By integrating targeted literature analysis and bibliometric mapping, we highlight key WRKY isoforms implicated in tolerance to heat, drought, cold, heavy metals, and pathogens, while underscoring the predominance of transient or heterologous functional assays. Although evidence consistently demonstrates the strong regulatory potential of WRKY transcription factors, stable and heritable genetic manipulation in potato warrants further investigation. We also highlight critical gaps and emerging opportunities for translating WRKY-mediated regulation into environmentally smart crop improvement strategies, further emphasizing the need for gene characterization and relevant genome approaches to support resilient potato breeding.

The dynamics of the ornamental plant market have been transforming due to changes in consumer preferences and demands. In this context, the aesthetic value of species has been associated with additional functions, highlighting the concept of multiple uses, which integrates both food and ornamental purposes. Peppers (Capsicum spp.) stand out for presenting desirable characteristics such as compact growth habit, edible use, and adaptability to cultivation in pots under both indoor and outdoor conditions. However, the low standardization of genotypes and the limited availability of commercial varieties still represent constraints to the expansion of this segment. In this regard, the objective of this study was to characterize the morphology and ornamental potential of different pepper genotypes of the genus Capsicum spp. The experiment was conducted in a completely randomized design, with twelve replications per genotype, totaling 360 experimental units. Morphological and ornamental traits were evaluated using international morphological descriptors for Capsicum, associated with classification criteria for ornamental plants established by the national market. The genotypes USP CA 010, USP CA 023, USP CA 028, and USP CA 044 stood out for presenting a greater number of ornamental characteristics, including compact architecture, and fruit production with intense coloration contrasting with the foliage. The morphological and ornamental characterization highlighted the variability among genotypes and proved to be effective in identifying promising materials for breeding programs and for the ornamental plant market.

Potato germplasm developed under tropical conditions harbors valuable genetic diversity. In Brazil, where potato is cultivated under diverse and complex tropical cropping systems, the population structure of locally adapted germplasm remains poorly understood. In this study, we evaluated the genetic structure and diversity of a panel of 450 potato clones, primarily derived from Brazilian national breeding initiatives. Genotyping yielded 18,481 high-quality SNPs for analyses. The panel exhibited a clear population structure with four genetic clusters, largely reflecting their breeding program’s genetic background. The genetic differentiation among the clusters was low (mean F_ST = 0.05), whereas the heterozygosity was high (mean H_O ≈ 0.50; range: 0.38–0.60). Negative inbreeding coefficients (mean F = -0.46) and elevated Tajima’s D values (4.32) suggest selection for increased heterozygosity. Additionally, the footprint analysis revealed regions linked to traits such as tuber quality, plant maturity, and disease resistance when Brazilian vs. foreign clones were compared. Furthermore, genomic regions under selection across the genetic clusters revealed unique gene ontology terms across categories enriched within selected regions. These findings provide insights into the genetic basis of adaptation and differentiation in tropical potato germplasms and offer valuable guidance for parental selection, trait introgression, and strategic management of genetic diversity.

Tomato (Solanum lycopersicum), which is considered one of the more important and widely cultivated crop members of the family Solanaceae, exhibits numerous biochemical mechanisms to alleviate the stress produced by various biotic and abiotic factors. Many researchers have found that phytochelatins (PCs) play an important role in these stress-alleviating mechanisms and, therefore, contribute significantly to the plant’s coping strategies, particularly under heavy metal exposure. Ongoing research has extensively investigated tomato genotypes in plant stress research, with a particular focus on heavy metal stress. The production of PCs, synthesized from glutathione, is regulated by various factors and different stressors. Here, we aim to provide an overview of the panorama regarding the synthesis of PCs in tomato under different environmental conditions and experimental settings, as well as provide information on their broader roles in biotechnology and modulating plant tolerance and responses across diverse stress conditions and treatments within the context of tomato research.

With the increasing concern on heavy metal contamination in agriculture and other environmental settings, unraveling the mechanisms of cadmium (Cd) tolerance and response in plants has become highly important. Ongoing plant Cd research over the years has focused on strategic and relevant aspects, including molecular, biochemical, and physiological processes. From this perspective, phosphoproteomics appears to be an innovative and powerful approach to investigating plant responses to Cd stress. Here, we summarize progress in plant Cd research across different plant species regarding large-scale phosphoproteomic investigations. Some studies revealed major proteins participating in detoxification, stress signaling, and metabolism, along with their regulation through phosphorylation, which modulates the plant’s defense against Cd. However, many pathways remain unexplored. Expanding these studies will help our ability to alleviate Cd stress and provide further information concerning involved mechanisms. Our purpose is to inspire researchers to further explore the use of phosphoproteomics in unraveling such complex mechanisms of Cd tolerance and response across various plant species, with the ultimate aim of enhancing strategies for mitigating Cd stress in agriculture and polluted environments.

The production of flowers and ornamental plants has shown continuous growth and demanded constant innovations in the sector. The sweet potato (Ipomoea batatas (L.) Lam.) is a tuberous vegetable that has attracted consumers, growers and landscapers due to its ornamental characteristics of its leaves and vines. However, the introduction of sweet potatoes for ornamental purposes is recent in the Brazilian market. The objective of this study was to investigate the ornamental potential of five sweet potato genotypes (IAC104, IAC116, IAC401, IAC909 and IAC1024), through morphological characterization, in addition to evaluating the effect of plant density in pot (1, 2 and 3 plants in pot) on the development of the aerial part and storage roots. The genotypes IAC116, IAC401 and IAC909 showed characteristics of erect and compact plants, while IAC401 and IAC1024 were classified as semi-erect, with only IAC1024 showing a twining vine. Increasing the density of plants resulted in a significant increase in both the number and fresh matter of storage roots in pot, but there was no significant difference in the fresh matter of the aerial part. As a result of this study, the first five ornamental sweet potato cultivars in Brazil were registered with the Ministry of Agriculture, Livestock and Supply (MAPA), named ‘IAC Claudia’, ‘IAC Katherine’, ‘IAC Mara’, ‘IAC Mônica’ and ‘IAC Yoka’, with registration numbers 51087, 51090, 51091, 51092 and 51093, respectively.

Given the increasing problems of water and soil contamination with cadmium (Cd), it is necessary to investigate the genetic and physiological mechanisms of tolerance to this metal in different crops, which can be used for the development of effective crop management strategies. This study aimed to assess the potential of grafting as a strategy to increase Cd tolerance and reduce absorption in tomato by evaluating the contribution of the root system and aerial parts for tolerance mechanisms. To this end, reciprocal grafting and diallel analyses were used to examine the combining ability of contrasting tomato genotypes under exposure to 0 and 35 µM CdCl₂. Roots and above-ground parts were found to have specific mechanisms of Cd tolerance, absorption, and accumulation. Grafting of the USP15 genotype (scion) on USP16 (rootstock) provided the greatest synergism, increasing the tolerance index and reducing the translocation index and Cd accumulation in leaves. USP163 exhibited potential for breeding programs that target genotypes with high Cd tolerance. In tomato, both Cd tolerance and accumulation in aerial parts are genotype- and tissue-specific, controlled by a complex system of complementary mechanisms that need to be better understood to support the development of strategies to reduce Cd contamination in aerial parts.

The objective of this research was to select orange-fleshed sweet potato clones with high stability, yield, and β-carotene content in different planting seasons, using a selection index. Joint analysis of experiments and analysis of responsiveness and stability by the GGE biplot method were performed for the variables yield, dry matter percentage, and root flesh color. The variables yield, dry matter, color and stability were used to estimate a selection index. The GGE biplot analysis indicated that there are differences among clones in stability for Yield. However, the percentage of dry matter and color of the roots show low interaction in the different environments. Because of that, stability for yield was included in the selection index, together with yield, dry matter, and root orange color intensity. Finally, the selection index based on stability, yield, dry matter percentage and root color was efficient in the selection of a new biofortified sweet potato cultivar.

The sweet potato cultivar ‘IAC 134 AL01’ has tuberous roots with high β-carotene content, with the fresh pulp having an intermediate orange colour (based on international descriptors for the crop), which turns bright orange after cooking, and a mildly sweet taste. These roots have a long-irregular shape, red skin and are of medium size, weighing, on average, 300 g and measuring 14 x 6 cm. The first biofortified sweet potato cultivar of the Campinas Agronomic Institute reaches an average yield of 43.9 t/ha and is recommended for planting in the state of São Paulo to supply the domestic market and for export.