Remote sensing in maize: effect of vegetal biostimulants application in three stages of development.

Maize is a crop of global economic importance and is widely cultivated throughout the Brazilian territory. The use of biostimulants can increase yield and improve crop yield. Unmanned aerial vehicles can be employed in arable areas, allowing their use in an economically way. This study to evaluate the use of biostimulant and the best application timing using photogrammetric indexes in maize, and indicate the most suitable plant index for yield increase through a Pearson's correlation. The DJI Drone coupled with RGB camera was used, and the images were processed through the AgisoftPhotoscan® software to generate the orthomosaic, and the QGIS® software version 3.4.15 with GRASS was used to generate thematic maps with the classification of the indexes of vegetation (NGRDI, EXG, SAVI, TGI, GLI, RI). A matrix of Pearson correlation coefficients between the variables was also created, and the results were analyzed with the R software. In general, the products Pyroligneous Extract (PE) and the hormonal product (HP) were the best for the two seasons studied. However, the HP was the best product to mitigate plant water stress in the dry period. Application at phenological stage V3 showed the lowest growth in the rainy season and in application to the seeds in the dry season. Dose 4 of the pyroligneous extract increased productivity in the rainy season and level 3.4 for the hormone product. Among the indexes evaluated, only the SAVI index showed significant differences between the others and showed significance for productivity in the two periods.

Use of neem vegetable cake (Azadirachta indica A. Juss) increases corn productivity.

The need to transition to more sustainable agriculture that is adaptable to environmental challenges, reducing dependence on chemical fertilizers and minimizing environmental impact, represents the new paradigm of the moment. In this scenario, studies with the adoption of bioinputs in corn cultivation emerge as a viable option for the sustainability of agricultural activity. Therefore, the objective was to evaluate the effect of doses of neem vegetable cake on the yield components of corn crops. An experimental design was used of randomized blocks was used, consisting of four doses of neem vegetable rendering (3 kg ha-1, 6 kg ha-1, 9 kg ha-1 and 12 kg ha-1) and a treatment control without the presence of organic fertilizer. The result indicates the presence of a significant effect of treatments with the application of neem cake on the main components of corn yield, including grain productivity, suggesting that the high carbon content present in the organic product can induce phytochemical effects and biological changes. in the soil, making it more productive. It was found that, when administering the maximum experimental dose, compared to the control group, there was a significant effect (p≤0.01) of 21.3% on grain productivity, jumping from 2,140 kg ha -1, when did not apply organic fertilizer, to 2,596 kg ha-1 with the application of 12 kg of neem cake per hectare. It is noted that the increase in grain productivity was in the proportion of 38 kg ha-1 of corn for each kilo of neem cake applied. To facilitate interpretation and decision-making, an analysis of the economic viability of neem cake for rainfed corn was also determined, also identifying the maximum experimental dose of 12 kg ha-1, as the most economically viable, providing an increase in profit of around R$ 119.92 per hectare, in relation to the control.

Sugarcane productivity and economic viability in response to planting density.

Planting with higher density in sugarcane is one of the practices used to overcome low productivity. However, this planting material is equivalent to 25% of the total cost of production, being one of the main expenses for cultivation. In this sense, the present work aims to evaluate the productivity and economic viability of sugarcane as a function of planting density. The experiment was carried out at Usina Monte Alegre in the municipality of Mamanguape, Paraíba, Brazil, from March 2021 to January 2022 with the variety RB92579. Seven planting density were studied: T1: 7 gems m-1, T2: 10 gems m-1, T3: 12 gems m-1, T4: 11 gems m-1, T5: 15 gems m-1, T6: 17 gems m-1, T7: 24 gems m-1, in randomized blocks with four replications. Growth, productivity and economic viability were evaluated. The highest productivity of cane and sugar, 77.69 ton ha-1 and 10.390 ton ha-1, respectively, was with planting density of 17 and 24 gems-1. While the minimum productivity of cane (61.313 ton ha-1) and sugar (7.924 ton ha-1) was recorded at sowing density of 7 and 11 gems-1. However, cultivation density with 7 and 10 gems m-1 were the ones that provided the highest profitability around 50%, followed by density of 12, 15 and 17 gems m-1 with an average of 45% profit and 11 and 24 gems m-1 with the lowest proportion of profit on average 38%. The cultivation with 17 gems m-1 of cane provides in cane-plant, variety RB92579, greater productivity with a profit rate of 45%, being the most suitable.

The physiological quality of Vigna unguiculata L. seeds shows tolerance to salinity.

Salinity reduces feijão-caupi production, and the search for tolerant varieties becomes important within the agricultural context, as, in addition to being used in the field, they can be used in genetic improvement. The objective was to for a identify variety that is tolerant to salinity considering the physiological quality of seeds and seedling growth. A 2 × 4 factorial scheme was used, referring to the varieties Pingo-de-ouro and Coruja, and four electrical conductivities of water (0; 3.3; 6.6 and 9.9 dS m-1). The physiological quality of seeds and the growth of seedlings were analyzed, in addition to the cumulative germination. The Pingo-de-ouro variety showed no germination, length of the shoot and root, dry mass of the shoot and root compromised up to electrical conductivity of 6 dS m-1 in relation to 0.0 dS m-1. On the other hand, the Coruja variety showed reduced germination, increased shoot and root length. The creole variety Pingo-de-ouro proved to be tolerant to salinity.

Agronomic parameters of sugarcane under planting densities in different cultivation cycles.

Low density sugarcane plantation (LDSP) has been implemented by some sugarcane producers in Brazil, aiming to save seeds and operational costs. The study was carried out in the municipality of Areia, Paraíba, Brazil. Five planting densities were used, varying from 5 to 25 m-2 of buds arranged in randomized blocks, with four replications. Data were measured annually over three cultivation cycles (2017 to 2020), during which the field was fertilized with NPK and the harvests were carried out manually without prior burning. The lower planting density presents higher productivity only in the cane plant (101.03 t ha-1) due to the higher plant height (2.37 m) and the higher number of stalks (11 stalks m-2), suggesting that these variables are due to the greater availability of light, water and photosynthate. However, there is a drastic reduction in sugarcane yield for this lower population in the 2nd ratoon by up to 65.62%, which is correlated with number of stalks per meter. We demonstrate the agronomic viability of LDSP in the population of 10 buds m-2 in relation to conventional planting of sugarcane until the 2nd ratoon. Data are important for future studies to present additional considerations for other production factors, such as the effects of mechanized harvesting and the management of nutrients and water, assessing the sustainability of this large-scale planting system.

Filter cake increases sugarcane yield.

Sugarcane cultivation stands out in Brazilian agribusiness, covering more than eight million hectares for the production of sugar, ethanol, and by-products. Fertilization is one of the limiting factors in sugarcane yield, for which filter cake is a viable solution to meet plant nutritional needs. This study aimed to assess the effect of enriched filter cake on gas exchange and yield in RB041443 sugarcane, cultivated in soils of the coastal tablelands of Paraíba, Brazil. The experiment was conducted in the Monte Alegre S/A sugarcane mill, in the municipality of Mamanguape, using a randomized blocks experimental design, with 12 treatments (T1- cake, T2- cake + MAP, T3- cake + gypsum, T4 - cake + phosphate, T5- cake + bagasse, T6- cake + MAP + gypsum, T7- cake + MAP + phosphate, T8- cake + MAP + bagasse, T9- cake + gypsum + phosphate, T10- cake + gypsum + bagasse, T11- cake + phosphate + bagasse, and T12- control (only MAP)), and 4 replications, totaling 48 plots. A significant effect (5% probability) was also observed for the variables number of leaves and tons of stem per hectare (TSH). T1- cake, T4- cake + phosphate, T6- cake + MAP + gypsum and T10- cake + gypsum + bagasse, had the best results for TSH, with yields greater than 140 t ha-1. Regarding stomatal conductance, the highest values were obtained in T6 and T8, which, together with T11, had the highest gs values. Concerning the internal carbon concentration, T1, T2, T6, and T8 stood out. T6 also had a significant effect on transpiration. From this study, it was concluded that the use of enriched filter cake as a base fertilizer in sugarcane culture contributes to increasing the yield of the RB041443 variety, generating positive responses for plant gas exchange, being T1 and T10 indicated to increase the production in the sugar-energy sector.

Influence of essential oils on the quality of Vigna unguiculata L. (Walp.) seeds compared by traditional method, image and multivariate analysis.

The extracts of medicinal plants are used for the treatment of seeds in order to reduce the action of phytopathogens and increase the vigor of the seeds. Currently, computerized image analysis has been used to assess the physiological quality of seed lots. The objective was to evaluate the efficiency of the Vigor-S® software in the evaluation of the physiological quality of cowpea seeds treated with essential oils, comparing with a traditional test and the principal component analysis. Two cowpea cultivars were analyzed, BRS Tumucumaque and BRS Guariba, treated with doses of natural extracts of Alfavaca, garlic, horsetail, citronella and pyroligneous acid. The traditional method consisted of evaluations for germination, first germination count, seedling emergence, emergence speed index, accelerated aging, fresh matter and dry matter of seedling and the image analysis for: seedling length, growth index, uniformity index, vigor index, and germination. A Principal component analysis was applied to reduce the number of variables. Horsetail, Alfavaca and citronella extracts were efficient in increasing the physiological quality of the seeds of at least one cultivar. The Vigor-S® software proved to be efficient compared to traditional tests to assess the physiological quality of seeds. Principal Component Analysis is an ally to identify the best extracts and doses to be used. The image analysis method proved to be effective when compared to the traditional method and can therefore be used.

Filter cake increases sugarcane yield / A torta de filtro aumenta a produtividade da cana-de-açúcar

Sugarcane cultivation stands out in Brazilian agribusiness, covering more than eight million hectares for the production of sugar, ethanol, and by-products. Fertilization is one of the limiting factors in sugarcane yield, for which filter cake is a viable solution to meet plant nutritional needs. This study aimed to assess the effect of enriched filter cake on gas exchange and yield in RB041443 sugarcane, cultivated in soils of the coastal tablelands of Paraíba, Brazil. The experiment was conducted in the Monte Alegre S/A sugarcane mill, in the municipality of Mamanguape, using a randomized blocks experimental design, with 12 treatments (T1- cake, T2- cake + MAP, T3- cake + gypsum, T4 - cake + phosphate, T5- cake + bagasse, T6- cake + MAP + gypsum, T7- cake + MAP + phosphate, T8- cake + MAP + bagasse, T9- cake + gypsum + phosphate, T10- cake + gypsum + bagasse, T11- cake + phosphate + bagasse, and T12- control (only MAP)), and 4 replications, totaling 48 plots. A significant effect (5% probability) was also observed for the variables number of leaves and tons of stem per hectare (TSH). T1- cake, T4- cake + phosphate, T6- cake + MAP + gypsum and T10- cake + gypsum + bagasse, had the best results for TSH, with yields greater than 140 t ha-1. Regarding stomatal conductance, the highest values were obtained in T6 and T8, which, together with T11, had the highest gs values. Concerning the internal carbon concentration, T1, T2, T6, and T8 stood out. T6 also had a significant effect on transpiration. From this study, it was concluded that the use of enriched filter cake as a base fertilizer in sugarcane culture contributes to increasing the yield of the RB041443 variety, generating positive responses for plant gas exchange, being T1 and T10 indicated to increase the production in the sugar-energy sector.

A cultura da cana-de-açúcar ocupa uma posição de destaque para o agronegócio brasileiro, abrangendo mais de oito milhões de hectares na produção de açúcar, etanol e subprodutos. Um dos fatores limitantes na produtividade da cana-de-açúcar é a questão da adubação, sendo a torta de filtro uma solução viável para suprir as necessidades nutricionais da planta. Com esse estudo, objetivou-se avaliar o efeito do uso da torta de filtro enriquecida sob as trocas gasosas e produtividade da variedade de cana-de-açúcar RB041443 cultivada em solos dos tabuleiros costeiros da Paraíba. O experimento foi conduzido na Usina Monte Alegre S/A, no município de Mamanguape-PB, utilizando o delineamento experimental em blocos casualizados com 12 tratamentos (T1- Torta, T2- Torta + MAP, T3- Torta + Gesso, T4 - Torta + Fosfato, T5- Torta + Bagaço, T6- Torta + MAP + Gesso, T7- Torta + MAP + Fosfato, T8- Torta + MAP + Bagaço, T9- Torta + Gesso + Fosfato, T10- Torta + Gesso + Bagaço, T11 - Torta + Fosfato + Bagaço, e T12 - Testemunha (Apenas MAP)), 4 repetições, totalizando 48 parcelas. Efeito significativo a 5% também foi observado para a variável número de folhas e tonelada de colmo por hectare. Para a variável TCH, os melhores resultados foram obtidos nos tratamentos T1- Torta, T4-Torta + Fosfato, T6- Torta + MAP + Gesso e T10- Torta + Gesso + Bagaço, com produtividades superiores a 140 t ha-1. Para a condutância estomática, resultados superiores foram obtidos no T6 e T8, que, junto ao T11, agruparam-se com os maiores valores de gs. Em relação a concentração interna de carbono, destacaram-se os tratamentos T1, T2, T6 e T8. Para a variável transpiração, o T6 apresentou influência significativa da torta de filtro. Com o referido estudo, concluiu-se que a utilização da torta de filtro enriquecida como adubação de fundação na cultura da cana-de-açúcar possibilita aumento no rendimento produtivo da variedade RB 041443, bem como respostas positivas para as trocas gasosas da planta, sendo os tratamentos T1 e T10 indicados para aumentar a produção do setor sucroenergético.

Influence of essential oils on the quality of Vigna unguiculata L. (Walp.) seeds compared by traditional method, image and multivariate analysis / Influência de óleos essências na qualidade de sementes de Vigna unguiculata L. (Walp.) comparado pelo método tradicional, análise imagem e multivariada

The extracts of medicinal plants are used for the treatment of seeds in order to reduce the action of phytopathogens and increase the vigor of the seeds. Currently, computerized image analysis has been used to assess the physiological quality of seed lots. The objective was to evaluate the efficiency of the Vigor-S® software in the evaluation of the physiological quality of cowpea seeds treated with essential oils, comparing with a traditional test and the principal component analysis. Two cowpea cultivars were analyzed, BRS Tumucumaque and BRS Guariba, treated with doses of natural extracts of Alfavaca, garlic, horsetail, citronella and pyroligneous acid. The traditional method consisted of evaluations for germination, first germination count, seedling emergence, emergence speed index, accelerated aging, fresh matter and dry matter of seedling and the image analysis for: seedling length, growth index, uniformity index, vigor index, and germination. A Principal component analysis was applied to reduce the number of variables. Horsetail, Alfavaca and citronella extracts were efficient in increasing the physiological quality of the seeds of at least one cultivar. The Vigor-S® software proved to be efficient compared to traditional tests to assess the physiological quality of seeds. Principal Component Analysis is an ally to identify the best extracts and doses to be used. The image analysis method proved to be effective when compared to the traditional method and can therefore be used.

Os extratos de plantas medicinais são utilizados para o tratamento de sementes com o objetivo de diminuir a ação de fitopatógenos e aumentar o vigor das sementes. Atualmente, a análise computadorizada de imagens tem sido utilizada para avaliar a qualidade fisiológica de lotes de sementes. O objetivo foi avaliar a qualidade fisiológica de sementes de feijão-caupi tratadas com óleos essenciais, comparado com teste tradicional, análise imagem e a análise de componentes principais. Foram analisadas duas cultivares de feijão-caupi, BRS Tumucumaque e BRS Guariba, tratadas com doses de extratos naturais de alfavaca, alho, cavalinha, citronela e ácido pirolenhoso. O método tradicional consistiu em avaliações de germinação, primeira contagem de germinação, emergência de plântulas, índice de velocidade de emergência, envelhecimento acelerado, matéria fresca e matéria seca da plântula e a análise de imagem para: comprimento da plântula, índice de crescimento, índice de uniformidade, índice de vigor e germinação. Uma análise de componentes principais foi aplicada para reduzir o número de variáveis. Os extratos de cavalinha, alfavaca e citronela foram eficientes em aumentar a qualidade fisiológica das sementes de pelo menos uma cultivar. O software Vigor-S® mostrou-se eficiente em relação aos testes tradicionais para avaliação da qualidade fisiológica de sementes. A Análise de Componentes Principais é uma aliada para identificar os melhores extratos e doses a serem utilizados. O método de análise de imagens mostrou-se eficaz quando comparado ao método tradicional, podendo, portanto, ser utilizado.