Vivane Mirian Lanhellas Gonçalves

The interaction of genotype by environment challenges material selection for specific regions. The GGE biplot methodology proves to be effective in detecting and addressing this complexity. This study evaluated the performance of eight maize hybrids in three locations in the North/Northwest of Rio de Janeiro during the winter 2021–2021 and summer 2021–2022 crop seasons. The results were subjected to analysis of variance and Tukey’s test, and the GGE biplot analysis, performed represented more than 80% of the total variation. Commercial hybrids (single and double) were more productive and more. adaptable. In contrast, UENF interpopulation hybrids presented lower productivity but higher stability, with lower-cost seeds and being more accessible, especially for producers in the North/Northwest regions of Rio de Janeiro, also becoming the most suitable. The results highlight the importance of stability and adaptability in the selection of cultivars for common corn. The use of UENF hybrids is recommended to optimize production in the region, with the GGE biplot method showing effectiveness in identifying the best genotypes, indicating that the productivity results are consistent with the proportion of heterosis explored, demonstrating that simple hybrids are the most productive, followed by double and interpopulational hybrids.

This article presents maize hybrid UENF 506 16, focusing on its development through reciprocal recurrent selection and its performance in cultivation and use value tests. UENF 506 16 has shown high prolificacy and environmental stability, making it a reliable, recommended choice for cultivation in the state of Rio de Janeiro.

This study described the main characteristics of the maize cultivars UENF MSV2210 and UENF MS2208. Adapted to the North and Northwestern regions of the state of Rio de Janeiro, they have a high agronomic performance and were developed for both silage and green maize production.

Papaya (Carica papaya L.) is one of the main tropical fruits consumed in Brazil. The country is also one of the main papaya exporters, but one of the factors hindering its production lies on foliar diseases such as papaya black spot, which is caused by fungus Asperisporium caricae. This pathogen is widely distributed in the main producing regions of the Brazilian coastal area. Phylogeographic studies contribute to the knowledge about the genetic diversity and geographical distribution of genealogical lineages (haplotypes) and help better understanding the reproductive and evolutionary processes of closely related species or of a single species. Such information is useful in studies about phytopathogenic fungi because it enables identifying the most prevalent genealogical lineages in a given location, as well as inferring dispersal routes and providing information on the origin and frequency of exotic material introduction events. Results in this type of study can significantly help developing new disease control strategies. Literature still lacks studies on the Papaya x A. caricae pathosystem. Based on the phylogenetic and phylogeographic analysis applied to nucleotide sequences of the Internal transcribed spacer (ITS) gene, we herein address the genealogical and dispersal events recorded for this pathogen in order to better understand its evolution in, and adaptation to, Brazilian orchards. Three haplotypes were identified among the A. caricae isolates; their distribution was mostly related to the geographic distance between sample collection regions rather than to any reproductive or evolutionary processes presented by the species. The low variability among the herein studied isolates may result from the physiological specialization (survival exclusively associated with the host plant) and from the regional transport of contaminated fruits (with lesions and spores), besides the low contribution of reproductive events, which corroborate the lack of knowledge about the sexual stages of A. caricae.