Alison Fernando Nogueira

Root-knot nematodes (RKNs, Meloidogyne spp.) represent the phytonematodes with the highest global economic impact. In tomato, various Meloidogyne species infect the crop, and the use of resistant cultivars is considered an important control strategy. However, M. enterolobii has recently been causing significant concern due to its aggressiveness, and resistance genes are ineffective in controlling this species. Therefore, the present study aimed to evaluate the resistance of various wild tomato accessions to M. javanica, M. enterolobii, M. incognita, and M. paranaensis nematode species. And commercial rootstocks were tested solely against M. enterolobii. To investigate the inheritance of resistance to this pathogen, selected genotypes were intercrossed in a diallel scheme and their progenies were phenotypically evaluated. For this purpose, eight wild tomato species (S. galapagense, S. pimpinellifolium, S. chmielewskii, S. chilense, S. peruvianum, S. habrochaites, S. neorickii, and S. pennellii) and 15 commercial rootstocks were evaluated. The S. peruvianum accession showed the lowest reproduction factor (RF) and nematodes per gram of root (NGR) values, indicating an important source of resistance, especially against M. enterolobii. The evaluated tomato rootstocks were susceptible to M. enterolobii, although some exhibited relatively low RF and NGR values, indicating a degree of tolerance. The diallel analysis revealed significant effects for general and specific combining abilities, indicating the importance of additive and non-additive effects in the inheritance of resistance. The rootstocks TD1, Embajador, and Shield stood out, being recommended for use in breeding programs aimed at developing rootstocks tolerant to M. enterolobii.

Low phosphorus (P) availability in tropical soils is one of the main constraints to agricultural productivity and the sustainability of cropping systems. In this study, we evaluated the functional potential of four bacterial strains, including those present in two commercial inoculants: Nodubiophos (Ag87-CCT 8090 and Ag94-CCT 8108), and Biomaphos (B119 and B2084), focusing on their production of phosphatase and phytase enzymes, organic acids, and their agronomic efficacy in soybean cultivation. In vitro assays showed that all strains exhibited phytase and both acid and alkaline phosphatase activities, with B2084 and Ag94 standing out in phytase-mediated mineralization. In contrast, B119 and B2084 showed the highest phosphatase activity. Organic acid production varied among strains and was influenced by the phosphate source, indicating a highly responsive metabolic regulation. Strains Ag87 and Ag94 were particularly effective in producing lactic, malic, and gluconic acids, displaying distinct profiles modulated by the available P source. In field trials, combined inoculation with Ag87 and Ag94 led to increased soybean yield, achieving performance comparable to conventional fertilization at 50% and 100% of the recommended P rate, despite applying only 30% of the total P. The results highlight complementary metabolic strategies among the evaluated strains, with the ability to solubilize and mineralize phosphorus through different mechanisms. They support their potential use as bioinoculants to enhance nutrient use efficiency and reduce fertilizer dependency in soybean cultivation.

Increasing phosphorus (P) use efficiency in agricultural systems is urgent and essential to significantly reduce the global demand for this nutrient. Applying phosphate-solubilizing and plant growth-promoting bacteria in the rhizosphere represents a strategy worthy of attention. In this context, the present work aimed to select and validate bacterial strains capable of solubilizing phosphorous and promoting maize growth, aiming to develop a microbial inoculant to be used in Brazilian agriculture. Bacterial strains from the maize rhizosphere were evaluated based on their ability to solubilize phosphate and produce indole acetic acid. Based on these characteristics, 24 strains were selected to be further evaluated under laboratory, greenhouse, and field conditions. Among the selected strains, four (I04, I12, I13, and I17) showed a high potential to increase maize root growth and shoot P content. Strains I13 (Ag87) and I17 (Ag94) were identified by genomic sequencing as Bacillus megaterium and Lysinibacillus sp., respectively. These strains presented superior yield increments relative to the control treatment with 30% P. In addition, combining Ag87 and Ag94 resulted in even higher yield gains, indicating a synergistic effect that could be harnessed in a commercial inoculant for Brazilian agriculture.

Physalis L. é um dos gêneros mais importantes da família Solanaceae, contendo 120 espécies botanicamente identificadas. As espécies de Physalis possuem uma grande variedade genética, devido ao elevado número de espécies botanicamente identificadas, que garante características peculiares de interesse econômico. Apesar do conhecimento dessas características, pouco se tem feito para o melhoramento genético dessa pequena fruta. Para se iniciar o melhoramento é necessário realizar a análise da diversidade genética em bancos de germoplasma. Desse modo, objetivou-se explorar parâmetros morfoagronômicos de sete espécies e vinte e nove híbridos interespecíficos de Physalis, visando contribuir para programas de melhoramento genético. Utilizou-se sete espécies: Physalis angulata, Physalis ixocarpa, Physalis pruinosa, Physalis peruviana, Physalis pubescens, Physalis mínima e Physalis daturaefolia e 29 híbridos interespecíficos. Para a caracterização morfoagronômicos, foi utilizada uma lista de 42 descritores, sendo 22 variáveis quantitativas e 20 qualitativas. Utilizando o agrupamento hierárquico de Ward com base na distância de Mahalanobis, observamos a formação de cinco grupos com parentes próximos em relação aos dados qualitativos. O método de Mojena (1977) indicou a formação de cinco grupos distintos. A análise de componentes principais (PCA) explicou 63.01% da variação total existente entre as sete espécies e os 29 híbridos de Physalis por meio dos dois primeiros componentes principais (PC1 e PC2). Em base dos caracteres explorados foram diferenciados cinco grupos quantitativos e qualitativos distintos. Os híbridos de Physalis foram superiores para maioria das variáveis quantitativas.

Broccoli (Brassica oleracea var. italica) is one of the most important vegetables in the world and also shows important functional properties. The present study aimed to characterize 19 broccoli genotypes using biochemical traits (content of total phenolic compounds, total flavonoids and antioxidant activity) and AFLP (Amplified Fragment Length Polymorphism) molecular markers. The experiment was carried out in a greenhouse using a complete randomized block design with three replicates. The phenotypic data were subjected to analysis of variance (p≤0.05), Scott-Knott average clustering method (p≤0.05) and principal component analysis (PCA). Using molecular data, Ward’s hierarchical clustering, Bayesian clustering and principal coordinate analysis (PCoA) were performed. Molecular data showed genetic diversity among the genotypes (three groups), also a wide variability in the total phenolic compounds, total flavonoids content and antioxidant activity using FRAP method. HT3010, Hanabi and Bonanza genotypes showed desirable biochemical traits for the demanding functional food consumers, in addition to being promising genotypes to be exploited in plant breeding programs.

Sweet pepper (Capsicum annuum L.) is one of the most consumed vegetables in the world, being recognized as a food with high nutritional value. Recently, the market for sweet and colorful mini peppers has increased, especially among the most demanding consumers in the novelties in vegetables and functional foods. In this sense, we evaluated mini sweet peppers genotypes (Akamu, Kaiki, Kalani, Kaolin e Moke from Isla^® seeds) regarding the physical-chemical, nutritional and sensory analysis aspects. A wide variability was observed among genotypes, highlighting the Kalani genotype for total carotenoids, and the genotypes Akamu, Kaiki and Kaolin for phenolic totals content and antioxidant activity. Moke and Kaolin showed higher vitamin C content and fruit firmness. Based on sensory analysis, Kalani, Kaiki, Kaolin and Akamu obtained greater global acceptance. The genotypes can be considered an important marketing strategy of mini sweet peppers trade, associating different shapes, colors and nutritional quality.

Beans (Phaseolus vulgaris L.) are an important source of proteins, carbohydrates, and micronutrients in the diets of millions of people in Latin America and Africa. Studies related to genetic variability in the accumulation and distribution of nutrients are valuable for biofortification programs, as there is evidence that the seed coat and embryo differ in the bioavailability of essential nutrients. In this study, we sought to evaluate the genetic variability of total mineral content in the grain and its constituent parts (seed coat, cotyledon, and embryonic axis) of bean genotypes from Mesoamerican and Andean centers of origin. Grain samples of 10 bean cultivars were analyzed for the content of proteins and minerals (Mg, Ca, K, P, Mn, S, Cu, B, Fe, and Zn) in the whole grains and seed coat, cotyledons, and embryonic axis tissues. Genetic variability was observed among the cultivars for protein content and all evaluated minerals. Moreover, differential accumulation of minerals was observed in the seed coat, cotyledons, and embryonic axis. Except for Ca, which accumulated predominantly in the seed coat, higher percentages of minerals were detected in the cotyledons. Furthermore, 100-grain mass values showed negative correlations with the contents of Ca, Mg, P, Zn, Fe, and Mn in whole grains or in the different grain tissues. In general, the Mesoamerican cultivars showed a higher concentration of minerals in the grains, whereas Andean cultivars showed higher concentrations of protein.

The common bean (Phaseolus vulgaris L.) is of great importance to the food and nutritional security of many populations, and exploitation of the crop’s genetic diversity is essential for the success of breeding programs. Thus, the aim of the present study was to evaluate the genetic diversity of 215 common bean accessions, which included cultivars, obsolete cultivars, improved lines, and landraces using morpho-agronomic and biochemical traits, and amplified fragment length polymorphism markers (AFLP). Genetic parameters, box plots, Pearson’s correlation analysis, and Ward’s hierarchical clustering were used to analyze the data. The Jaccard similarity coefficient and neighbour-joining clustering method were used for molecular analysis. A wide variability among the accessions was observed for morpho-agronomic and biochemical traits. Selective accuracy (Ac) and broad-sense heritability (h²) values were high to intermediate for all traits, except seed yield. Ward’s hierarchical clustering analysis generated six groups. AFLP analysis also revealed significant differences among the accessions. There was no correlation between the differences based on genetic markers and those based on morpho-agronomic and biochemical data, which indicates that both datasets are important for elucidating the differences among accessions. The results of the present study indicate great genetic diversity among the evaluated accessions.