Mixed modeling for fiber yield genetic selection in sugarcane

The current demand for clean and renewable energy has provoked considerable changes in the production system of agroindustrial companies. The generation of bioelectricity through the burning of sugarcane bagasse has considerably risen in the recent years. This work aimed to focus on the sugarcane genotypes selection for fiber productivity. The experiment was outlined in randomized blocks with four repetitions, and sixteen genotypes were evaluated. The evaluated traits  were: cane tons per hectare, sucrose tons per hectare, fiber tons per hectare, fiber content and apparent sucrose content. To the selection, the mixed linear models methodology was used. The heritability coefficients suggest a significant genetic gain and the harmonic means of relative performances of predicted genotypic values allowed the identification of stable genotypes related to the traits evaluated in four harvest cycles. Considering the current average demand of sugarcane agroindustry for varieties with fiber content between 12% and 17% and sucrose content near 13%, for energy generation and sugar production, the genotypes EECAC 06, EECAC 03, EECAC 04 and EECAC 07 are presented as commercial cultivation options. Highlights - Mixed models constitute an efficient tool for sugarcane selection focused onto fiber and sucrose production. - This methodology provides significant genetic gains based on predicted genetic values free from interaction with harvest cycles. - The evaluated genotypes present high fiber and sucrose productivity, genotypic adaptability and stability throughout harvest cycles, indicating longevity in the sugarcane crop.The current demand for clean and renewable energy has provoked considerable changes in the production system of agroindustrial companies. The generation of bioelectricity through the burning of sugarcane bagasse has considerably risen in the recent years. This work aimed to focus on the sugarcane genotypes selection for fiber productivity. The experiment was outlined in randomized blocks with four repetitions, and sixteen genotypes were evaluated. The evaluated traits  were: cane tons per hectare, sucrose tons per hectare, fiber tons per hectare, fiber content and apparent sucrose content. To the selection, the mixed linear models methodology was used. The heritability coefficients suggest a significant genetic gain and the harmonic means of relative performances of predicted genotypic values allowed the identification of stable genotypes related to the traits evaluated in four harvest cycles. Considering the current average demand of sugarcane agroindustry for varieties with fiber content between 12% and 17% and sucrose content near 13%, for energy generation and sugar production, the genotypes EECAC 06, EECAC 03, EECAC 04 and EECAC 07 are presented as commercial cultivation options. Highlights - Mixed models constitute an efficient tool for sugarcane selection focused onto fiber and sucrose production. - This methodology provides significant genetic gains based on predicted genetic values free from interaction with harvest cycles. - The evaluated genotypes present high fiber and sucrose productivity, genotypic adaptability and stability throughout harvest cycles, indicating longevity in the sugarcane crop

Biometric genetics in cowpea beans (Vigna unguiculata (L.) Walp) I: phenotypic and genotypic relations among production components

In the semi-arid region of Paraíba, cowpea has low productivity due to irregular rainfall and poor use of production technologies. An extensive study aimed at selecting more productive cultivars was conducted using biometric models. This first work had the following objectives: i. Quantify direct and indirect effects of primary and secondary components on grain production; ii. Identify variables with greater potential for cultivar selection in the semiarid region of Paraíba and iii. Determine the most appropriate selection strategies for the evaluated variables. The experiment was conducted in an experimental field. The influence of 6 primary and 6 secondary production components was evaluated on grain yield. Data were subjected to ANOVA. Genetic parameters, correlations and path analysis were estimated. Given the strong direct phenotypic and genotypic effects, pod yield results the most promising variable for higher grain yield selection. Direct and simultaneous selections are the most suitable strategies for the set of evaluated variables. However, further studies on selection indices are necessary to maximize genetic gains. Highlights Variables with greater potential were identified for the selection of superior cultivars of cowpea in the semiarid region of Paraíba. The pod yield variable (PP) seems promising for cultivar selection considering higher grain yield (GY).In the semi-arid region of Paraíba, cowpea has low productivity due to irregular rainfall and poor use of production technologies. An extensive study aimed at selecting more productive cultivars was conducted using biometric models. This first work had the following objectives: i. Quantify direct and indirect effects of primary and secondary components on grain production; ii. Identify variables with greater potential for cultivar selection in the semiarid region of Paraíba and iii. Determine the most appropriate selection strategies for the evaluated variables. The experiment was conducted in an experimental field. The influence of 6 primary and 6 secondary production components was evaluated on grain yield. Data were subjected to ANOVA. Genetic parameters, correlations and path analysis were estimated. Given the strong direct phenotypic and genotypic effects, pod yield results the most promising variable for higher grain yield selection. Direct and simultaneous selections are the most suitable strategies for the set of evaluated variables. However, further studies on selection indices are necessary to maximize genetic gains. Highlights Variables with greater potential were identified for the selection of superior cultivars of cowpea in the semiarid region of Paraíba. The pod yield variable (PP) seems promising for cultivar selection considering higher grain yield (GY)

Biometric genetics in Cowpea beans (Vigna unguiculata (L.) Walp) II: estimates of genetic gains through selection indices

Low cowpea productivity (Vigna unguiculata (L.) Walp) in the semi-arid region of Paraíba is due, among other factors, to poor-quality cultivars. This research tested biometric models intending to increase productivity of superior cultivars with the following objectives: i. Estimate genetic gains in production components; ii. Identify the selection index model providing the greatest gains through simultaneously selecting a set of variables, and iii. Select cultivars with higher productivity. The experiment was carried out in the experimental field of the Agrifood Science and Technology Center of the Federal University of Campina Grande. Eight cultivars and 13 variables were evaluated. Data were subjected to ANOVA and means were grouped using the Scott and Knott test. Genetic gains were estimated by correlated response, classic selection index, rank sum and index based on desired gains. Direct selection of the secondary pod yield component provides significant genetic gains in main grain yield. Among the methodologies used, the classic selection index provided greater distribution of genetic gains for main grain yield and primary production components. These results allow concluding that Costela de vaca, BRS Marataoã and Paulistinha cultivars should be selected for cultivation and commercial exploitation in the semiarid region of Paraíba. Highlights: Direct selection of the secondary pod yield component provides significant genetic gains in main grain yield. The classic selection index provided greater distribution of genetic gains for main grain yield and primary production components. Cultivars were selected for cultivation and commercial exploitation in the semi-arid region of Paraíba.Low cowpea productivity (Vigna unguiculata (L.) Walp) in the semi-arid region of Paraíba is due, among other factors, to poor-quality cultivars. This research tested biometric models intending to increase productivity of superior cultivars with the following objectives: i. Estimate genetic gains in production components; ii. Identify the selection index model providing the greatest gains through simultaneously selecting a set of variables, and iii. Select cultivars with higher productivity. The experiment was carried out in the experimental field of the Agrifood Science and Technology Center of the Federal University of Campina Grande. Eight cultivars and 13 variables were evaluated. Data were subjected to ANOVA and means were grouped using the Scott and Knott test. Genetic gains were estimated by correlated response, classic selection index, rank sum and index based on desired gains. Direct selection of the secondary pod yield component provides significant genetic gains in main grain yield. Among the methodologies used, the classic selection index provided greater distribution of genetic gains for main grain yield and primary production components. These results allow concluding that Costela de vaca, BRS Marataoã and Paulistinha cultivars should be selected for cultivation and commercial exploitation in the semiarid region of Paraíba. Highlights: Direct selection of the secondary pod yield component provides significant genetic gains in main grain yield. The classic selection index provided greater distribution of genetic gains for main grain yield and primary production components. Cultivars were selected for cultivation and commercial exploitation in the semi-arid region of Paraíba

Avaliação dos parâmetros genéticos da cana-de-açúcar submetida à adubação com silício e ao estresse hídrico / Assessment of the genetic parameters of sugarcane submitted to fertilization with silicon and water stress

A cana-de-açúcar é uma cultura de relevada importância econômica, sendo utilizada como matéria prima para diversos subprodutos que vão desde a indústria energética até a de alimentação. A demanda hídrica da cultura é de 1.500 a 2.500 mm água bem distribuídos ao longo de seu ciclo, em regiões onde a falta desse recurso é recorrente é necessário adotar-se estratégias para minimizar a perda de água pela planta. O uso de adubação silicatada tem sido vista como uma solução para a redução do estresse hídrico em algumas culturas, inclusive a cana-de-açúcar. Sendo assim, objetivou-se com esse trabalho avaliar o desempenho de variedades comerciais de cana-de-açúcar sob diferentes doses de silício e níveis de água. O ensaio foi conduzido no Campus de Universidade Federal de Campina Grande- UFCG em Pombal-PB durante 90 dias, foi utilizado o esquema fatorial triplo com duas variedades (RB92579 e RB867515), dois níveis de água (50 % e 100 % da capacidade de água do solo) e doses de silicato de potássio (0,0 L, 3L e 4L de K2SiO3), três repetições e delineamento em blocos casualizados.  A aplicação foliar de silício, na forma de silicato de potássio, contribuiu para o desenvolvimento das plantas de cana-de-açúcar. Os tratamentos com 0L de K2SiO3 e 3L de K2SiO3 foram os que apresentaram os melhores resultados. 

COVID-19 e dengue: ocorrência síncrona, em cidade endêmica, no sul da Bahia: COVID-19 and dengue: synchronous occurrence in an endemic city in southern Bahia

No Brasil, a pandemia provocada pelo novo coronavírus, SARS-Cov-2, teve início em fevereiro de 2020, desde então, vem provocando um aumento de novos casos acompanhados por um elevado número de óbitos. Aliado ao avanço dessa nova doença está o agravo de caráter endêmico responsável por eventos de epidemias cíclicas, como a dengue, provocada por um arbovírus. Devido a semelhança entre sintomas clínicos da dengue e da COVID, essa dificuldade em realizar diagnósticos pode afetar negativamente estudos que apontem correlação entre a COVID-19 e a dengue, dessa forma, esse trabalho visa apontar a ocorrência de infecções síncronas para esses dois agravos e quais suas correlações clínicas. Foram utilizados pacientes que estavam positivos, laboratorialmente, para COVID-19 e dengue, no mesmo período, na cidade de Itabuna/BA em 2020. Observou-se predomínio de pacientes masculinos e uma correlação entre sintomas, sendo febre e distúrbios gustativos/olfatórios os sintomas mais frequentes para a infecção síncrona. Não foi observado um predomínio em relação a idade, não sendo possível avaliar um grupo de risco específico. Ademais, dentre os casos encontrados, não se verificou nenhum óbito. Com esse trabalho se concluiu que embora a ocorrência síncrona de COVID e dengue seja positiva, a sobrecarga do serviço de saúde provocou uma subnotificação de dengue, dispondo assim uma necessidade maior de estudos que visem elucidar o mecanismo de ação e interação desses agravos, a fim de fornecer um atendimento de melhor qualidade para a população