Family agriculture is a rich germplasm source wherever it takes place; however, information on genetic variability of this type of culture in Brazil is scarce. Samples of melon (Cucumis melo L.) accessions grown by family agriculture were rescued and this study aimed at characterizing the genetic variability in one sample of these accessions so as to identify the melon subspecies and the corresponding varieties. Fifteen accessions and their S 1 progenies were characterized (quantitative and qualitative descriptors) in two field experiments carried out in randomized blocks. Data on the parental and S 1 generations were compared and it was possible to identify the subspecies Cucumis melo subsp. agrestis and their varieties C. melo var. makuwa and C. melo var. momordica, and the subspecies C. melo subsp. melo and its variety C.melo var. cantalupensis, although some sub-accessions remained unidentified. A total of 26 subaccessions were found. UPGMA grouping method showed a high genetic diversity among and within accessions and sub-accessions. Clusters were formed by the melon subspecies, although there were discrepancies. Nonetheless, there is indication of trait introgression from the two melon subspecies and their varieties in the material grown by the family farmers of the state of Maranhão.

RESUMO:A mangicultura praticada no Submédio do Vale do São Francisco é considerada um dos principais destaques no comércio externo do País. Dentre as diversas variedades cultivadas, a Tommy Atkins é a que representa a maior parte das exportações. Entretanto, a magnitude das perdas por podridões pós--colheita, causadas por fungos Botryosphaeriaceae, é sempre uma grande preocupação para exportadores e importadores da fruta. A busca por métodos de controle mais eficazes e limpos é uma tendência mundial. Nesse sentido, o objetivo deste trabalho foi avaliar a reação de frutos, de 47 acessos de mangueiras, quanto à resistência aos fungos Fusicoccum aesculis e Neofusicoccum parvum. As inoculações foram realizadas mediante deposição de disco do meio de cultura batata-dextrose-ágar (BDA), contendo estruturas do pató-geno sobre duas posições opostas na região equatorial da manga, mantido, posteriormente, por 24 horas em câmara úmida. Foram realizadas medições das lesões até o sétimo dia, com uma régua milimetrada. Com os registros dos crescimentos das lesões, foram calculadas as taxas diárias de crescimento da lesão (TDCL's) para cada acesso. As maiores TDCLs foram observadas nos acessos 'Roxa' e 'Lita', quando inoculados com F. aesculis, e nos acessos 'Roxa', 'Ruby', 'Papo de peru', 'CPAC 22/93', 'Pingo-de-ouro', 'Pêssego' e 'M13269', quando inoculados com N. parvum. Os acessos 'Nego-não-chupa', 'Manga-d'água', 'Juazeiro VI', 'Juazeiro VII' e 'Favo-de-mel' foram os que apresentaram, concomitantemente, as menores TDCLs para ambos os patógenos e diferenças significativas em relação aos demais acessos. Termos para indexação: Podridão peduncular, Botryosphaeriaceae, Mangifera indica. RESISTANCE AVALIATION OF 47 MANGO GERMPLASM TO THE FUNGIFusicoccum aesculis AND Neofusicoccum parvum ABSTRACT -The production of mango in the San Francisco Valley lower basin is considered one of the highlights in the export of the fruit by the country. Fruits of the cultivar Tommy Atkins are the most exported. However, the magnitude of losses due to post-harvest rots caused by fungi Botryosphaeriaceae is always a major concern for the exporter and importer of fruit. The search for control methods more effective and clean is a worldwide trend. The objective of this study was to evaluate the reaction of the fruits of 47 mango genotypes, for resistance to fungi Fusicoccum aesculis and Neofusicoccum parvum. The inoculations were performed by means of deposition culture medium discs potato-dextrose-agar (PDA) containing the pathogen structures on two positions perpendicular to the mango, and then maintained for 24 hours in a humid chamber.

Family farming in Brazil holds a high diversity of melon germplasm, composing an important source of alleles for breeding programs. Thus, the objective of this study was to estimate genetic parameters and select genotypes from a population of melon sub-accessions from different botanical varieties grown by family farmers, based on morphological parameters. Two experiments were conducted, one in 2019 and another in 2020, in a complete randomized block design, with three replications and five plants per plot, using 27 melon sub-accessions (generation S2) from family farmers, and a commercial variety. Nine quantitative descriptors were evaluated. Assumptions of ANOVA were tested, followed by individual and joint analyses of variance. Significant differences were found among sub-accessions for all descriptors evaluated, with heritabilities higher than 83% and significant genotype-environment interactions for 88.8% of the characteristics evaluated. Thus, genetic variability was found among sub-accessions, with predominance of genetic effects over environmental effects, denoting the possibility to obtain genetic gains by the improvement of several characteristics of agronomic interest. The sub-accessions BGMEL66.0, BGMEL111.0, and BGMEL112.0 are recommended for inclusion in breeding programs focused on obtaining good prolificacy and small fruits with high soluble solid contents. BGMEL sub-accessions (108.3 and 108.5) can generate progenies with high prolificacy, and sub-accessions of the variety momordica can be used for generation of progenies focused on shortening the crop cycle and increasing fruit size.

Melon (Cucumis melo L.) crops are grown in the Semiarid region of Brazil by small, medium, and large farmers, focused on domestic and international markets. However, melon is also grown by family farmers using their own seeds, which are important germplasm for melon breeding programs. Samples of these seeds were collected and stored in the Active Germplasm Bank of Cucurbitaceae from the Northeast Region at the Brazilian Agricultural Research Corporation (Embrapa Semiarid), and require more thorough studies for a better understanding of the existing variability. Thus, the objective of this work was to characterize sub-accessions and their respective endogamic progenies to assess the genetic variability between and among these accessions. Two experiments were conducted in a randomized complete block design, with three replications, using 11 quantitative and 8 qualitative descriptors: the first using seeds from 17 accessions from natural pollination, and the second using seeds from S1 progenies. Morphological data were used for comparisons between generations. The 17 accessions evaluated originated 24 sub-accessions, denoting variability between and among accessions and sub-accessions. A dendrogram developed based on the Unweighted Pair Group Method with Arithmetic Mean (UPGMA) showed the existing variability and, according to the newest melon classification, the groups identified were: makuwa, subgroup nashi-uri; and momordica and cantalupensis, subgroup prescott. The results showed a probable existence of introgression of alleles between different botanical groups, and some sub-accessions were not identified regarding their group by presenting variations in morphological characteristics, indicating the presence of new botanical groups.

The melon (Cucumis melo L.) is one of the most important horticultural crops in the northeast of Brazil. The characterisation of germplasm is an effi cient process for managing plant genetic resources, as it contributes to better conservation and improved use in breeding programs. In the present study, the genetic divergence between sub-accessions of the melon taken from traditional agriculture in the semi-arid region of Brazil was evaluated using ISSR and RAPD markers, verifying the level of agreement with the botanical classifi cation. Twenty-six sub-accessions preserved in the Active Germplasm Bank of Cucurbitaceae for the northeast of Brazil, located at Embrapa Semiárido in Petrolina, Pernambuco, were analysed. The binary matrix of the molecular data was used to obtain the genetic dissimilarities using the complement of the Jaccard index. The genetic dissimilarities were represented in dendrograms generated using the UPGMA method. Twenty-eight ISSR primers and 26 RAPD primers were polymorphic. A total of 686 fragments were obtained, of which 451 were polymorphic. The mean polymorphism of the RAPD markers was greater than that of the ISSR markers. The number of markers was considered suffi cient to accurately determine the genetic diversity. The ISSR dendrogram allowed the formation of three groups, the RAPD dendrogram, four groups, and the joint dendrogram, three groups. The study demonstrated the genetic variability between the sub-accessions, and the strong association between the characterisation made by the molecular markers and the taxonomic classifi cation of the genotypes under study.