Mycorrhizal fungi and phosphate fertilization in the production of Euterpe edulis seedlings

The present study evaluated the effect of arbuscular mycorrhizal fungi (AMF) inoculation on growth and nutrition of Euterpe edulis seedlings, supplemented or not with phosphate fertilization. The experiment was conducted in a greenhouse. The randomized block design, consisted of a 3x2 factorial arrangement and 4 replicates, with two phosphorus doses (0 and 50 mg dm-3 of soil), two microbiological treatments (Rhizophagus clarus;  laroideoglomus etunicatum; R. clarus + C. etunicatum) and control (without fungus). Sowing and inoculation occurred concurrently in 2 kg plastic bags. Height, collar diameter, leaf area, dry shoot mass, macronutrient content and mycorrhizal colonization percentage were determined after 226 days. Regarding mycorrhizal colonization percentage, R. clarus resulted significantly beneficial for the production of E. edulis seedlings. In the absence of phosphate fertilization, R. clarus and mixed inoculum increased all biometric variables and macronutrient contents in seedlings. Therefore, it is concluded that AMF inoculations provide beneficial effects for growth and nutrition of E. edulis seedlings, resulting in more vigorous plants at a low-cost strategy. Highlights: Rhizophagus clarus resulted significantly beneficial for the production of E. edulis seedlings and in the absence of phosphate fertilization, and mixed inoculum ( clarus + Claroideoglomus etunicatum) increased all biometric variables and macronutrient contents in seedlings. The AMF inoculations provide beneficial effects for growth and nutrition of E. edulis seedlings, resulting in more vigorous plants at a low-cost strategy. The AMF, a biological agent of mutualistic associations with plants, constitutes an innovative approach to sustainable agriculture, contributing to increase plant survival rate, a key-factor for the successful reintroduction and conservation of E. edulis, as well as for its commercial exploitation.The present study evaluated the effect of arbuscular mycorrhizal fungi (AMF) inoculation on growth and nutrition of Euterpe edulis seedlings, supplemented or not with phosphate fertilization. The experiment was conducted in a greenhouse. The randomized block design, consisted of a 3x2 factorial arrangement and 4 replicates, with two phosphorus doses (0 and 50 mg dm-3 of soil), two microbiological treatments (Rhizophagus clarus;  laroideoglomus etunicatum; R. clarus + C. etunicatum) and control (without fungus). Sowing and inoculation occurred concurrently in 2 kg plastic bags. Height, collar diameter, leaf area, dry shoot mass, macronutrient content and mycorrhizal colonization percentage were determined after 226 days. Regarding mycorrhizal colonization percentage, R. clarus resulted significantly beneficial for the production of E. edulis seedlings. In the absence of phosphate fertilization, R. clarus and mixed inoculum increased all biometric variables and macronutrient contents in seedlings. Therefore, it is concluded that AMF inoculations provide beneficial effects for growth and nutrition of E. edulis seedlings, resulting in more vigorous plants at a low-cost strategy. Highlights: Rhizophagus clarus resulted significantly beneficial for the production of E. edulis seedlings and in the absence of phosphate fertilization, and mixed inoculum ( clarus + Claroideoglomus etunicatum) increased all biometric variables and macronutrient contents in seedlings. The AMF inoculations provide beneficial effects for growth and nutrition of E. edulis seedlings, resulting in more vigorous plants at a low-cost strategy. The AMF, a biological agent of mutualistic associations with plants, constitutes an innovative approach to sustainable agriculture, contributing to increase plant survival rate, a key-factor for the successful reintroduction and conservation of E. edulis, as well as for its commercial exploitation.

Genetic diversity and selection using an ideotype in a Formosa papaya population

Ideotype is a combination of traits to be sought in a breeding program, supporting the selection process. However, there must be sufficient genetic variability to be explored to ensure success in this process. Thus, this study aimed to evaluate the genetic diversity of a population of Formosa papaya from the cultivar Rubi Incaper 511, maintained by farmers, and the use of an index based on the genotype-ideotype distance for preserving the original traits of the cultivar. A population of 250 individuals, maintained for approximately 10 years, was evaluated for 13 quantitative morpho-agronomic descriptors. Genetic divergence was estimated from the dissimilarity matrix using the mean Euclidean distance, and the dendrogram was formed using the hierarchical method of unweighted pair groups method with arithmetic averages (UPGMA). The index based on the genotype-ideotype distance was used for plant selection, with the cultivar Rubi Incaper 511 being the desired ideotype. The new means of the selected individuals and the selection differential were obtained after this selection. The individuals had fruit mass ranging from 0.73 to 1.99 kg, soluble solids content between 9.63 and 12.68 °Brix, and number of commercial fruits per plant ranging from 23 to 90. The dendrogram divided the genotypes into five groups. The selected individuals exhibited favorable selection differentials for ten traits and were closer to the selected ideotype. The management of this population by the farmers proved to be efficient in maintaining the genetic variability of the cultivar, and the selection through the index based on the genotypeideotype distance can be used to restore the phenotypic pattern of open-pollinated cultivars

CORRELAÇÕES E PARÂMETROS GENÉTICOS DE FAMÍLIAS DE MEIOS-IRMÃOS DO MAMOEIRO DA CULTIVAR RUBI INCAPER 511

As correlações e os parâmetros genéticos são estimativas utilizadas para otimizar os trabalhos de melhoramento de plantas. O objetivo desse trabalho foi quantificar tais parâmetros para famílias de meios-irmãos de mamoeiro da cultivar Rubi Incaper 511, aos 8 meses pós semeadura. Foram avaliadas dezoito famílias de meios-irmãos e a cultivar Rubi Incaper 511, em delineamento de blocos ao acaso com cinco repetições e nove plantas por parcela. Foram estimados as variâncias genotípica, fenotípica e ambiental; o coeficiente de determinação genotípico e as correlações fenotípicas, genotípicas e ambientais entre os caracteres: altura da planta (AP), altura de inserção dos primeiros frutos (AF) e diâmetro de caule (DC). As correlações genotípicas foram maiores que a fenotípica, exceto para AP x DC e houve correlação fenotípica significativa entre as características AP x AF e AP x DC. A variância genotípica foi maior que a ambiental em todas as características avaliadas. Os coeficientes de determinação genotípico indicaram que é possível ter sucesso na seleção das variáveis analisadas

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

CRESCIMENTO DE ESPÉCIES FLORESTAIS DA MATA ATLÂNTICA PRODUTORAS DE PRODUTOS FLORESTAIS MADEIREIROS E PFNM

Diante do quadro de devastação da Mata Atlântica, ações que visem à recuperação e preservação das florestas associada à oportunidade de renda para os produtores rurais são necessárias. Dentre elas, o consórcio de culturas é uma alternativa que precisa de maiores estudos para a sua concretização. O objetivo desse trabalho foi avaliar a taxa de mortalidade e os incrementos em diâmetro e altura de mudas de espécies florestais em consórcio com cafezais. Foi instalado um experimento no delineamento de blocos ao acaso, com cinco tratamentos e quatro repetições. Os tratamentos consistiram em quatro diferentes espécies arbóreas nativas da Mata Atlântica (Araucária, Jatobá, Araribá e Ipê Tabaco) e o Eucalipto. Um mês após o plantio, as mudas de Araucária tiveram a menor mortalidade e a maior foi observada nas mudas de Eucalipto. Já aos sete meses após o plantio, não foram observadas diferenças entre os tratamentos. A espécie que teve os maiores incrementos em diâmetro do coleto e altura total foi o Eucalipto, resaltanto o grande potencial de utilização da espécie em projetos de florestamento

AVALIAÇÃO DA FERTILIDADE DO SOLO EM CAFEZAIS VISANDO A IMPLANTAÇÃO DE POVOAMENTOS FLORESTAIS

Diante do quadro de abandono das lavouras cafeeiras na região das montanhas capixabas, ações que visem à substituição destas por florestas, garantindo a disponibilidade de água, a conservação do solo e da biodiversidade e criando oportunidade de renda para os produtores rurais são necessárias. Objetivou-se com esse trabalho, avaliar a fertilidade do solo em lavoura cafeeira abandonada visando à implantação de povoamentos florestais para múltiplos usos. Avaliou-se a qualidade química e física do solo. Observou-se que 68,4% dos atributos químicos do solo avaliados foram classificados como sendo de médios a altos, indicando o potencial de utilização da área para plantios com fins econômicos. Ocorreu um aumento na resistência à penetração do solo com o aumento da profundidade. Entretanto, em todas as profundidades avaliadas, os valores de resistência à penetração não são considerados limitantes para o desenvolvimento adequado das plantas cultivadas

Productivity and quality of Formosa and Solo papaya over two harvest seasons

O objetivo deste trabalho foi avaliar a produtividade e a qualidade de frutos de mamoeiro (Carica papaya) dos grupos heteróticos Solo (12 genótipos) e Formosa (9 genótipos), em duas épocas de colheita. O experimento foi conduzido em condições de campo em Pinheiros, ES, em delineamento de blocos ao acaso. Dez variáveis morfoagronômicas e físico-químicas dos frutos foram avaliadas no inverno (210 a 300 dias após o plantio) e no verão (450 a 540 dias após o plantio). Os dados foram submetidos à análise de variância conjunta, à decomposição da interação genótipo x ambiente e ao agrupamento das médias pelo teste de Scott-Knott. Embora a colheita em diferentes épocas tenha influenciado as características avaliadas, não alterou a classificação dos genótipos. No grupo Solo, destacam-se os híbridos 'H 36-45' e 'UC 15', por suas maiores produção e massa do fruto e por seu alto teor de sólidos solúveis. No grupo Formosa, a cultivar Rubi Incaper 511 apresenta maior produção, maior número de frutos comerciais e menor número de frutos deformados nas duas épocas de colheita avaliadas.The objective of this work was to evaluate the productivity and quality of papaya fruits (Carica papaya) of the Solo (12 genotypes) and Formosa (9 genotypes) heterotic groups over two harvest seasons. The experiment was conducted under field conditions in the municipality of Pinheiros, in the state of Espírito Santo, Brazil, in a randomized complete block design. Ten morpho-agronomic and physicochemical variables of the fruits were measured in winter (210–300 days after planting) and summer (450–540 days after planting). The data were subjected to the combined analysis of variance, to the breakdown of the genotype x environment interactions, and to the grouping of means by the Scott-Knott test. Although harvest season affected the evaluated characteristics, it did not alter the classification of the genotype. In the Solo group, the 'H 36-45' and 'UC 15' hybrids stand out due to their greater productivity, fruit weight, and soluble solids contents. In the Formosa group, the Rubi Incaper 511 cultivar shows greater productivity, higher number of fruits for commercial use, and lower number of deformed fruits over both evaluated harvest seasons

Intrapopulation recurrent selection by mixed models in papaya of the formosa group

Abstract Few cultivars of papaya from the Formosa group are available to producers, and the development of new genotypes is indispensable. Thus, the use of effective selection strategies to obtain more productive cultivars and better quality fruits is also necessary. The aim of this study was to select of half-sib families (HSF) of papaya using the methodology of mixed models. Nineteen HSFs from the Incaper’s papaya breeding program were evaluated in a randomized block design with five replicates and nine plants per plot. The selection was made based on fruit mass (FM), pulp thickness (PT), soluble solids content in pulp (SS) and number of fruits (NF). The genetic parameters and genotypic values were estimated by the REML/BLUP procedure. The selected HSFs increased FM by 26.1%; the PT in 10.5%; the SS in 7.5% and; the NF in 13.0%. The additive heritability within the progenies and the individual variation coefficient obtained indicate that the selection between and within the HSFs can provide greater genetic gains. The selection based on the REML/BLUP methodology was efficient to obtain simultaneous genetic gains for all variables under study despite the negative correlation between them