Although the potential of Alternative Jet Fuels (AJF) to reduce greenhouse gases (GHG) emissions has been widely reported upon in the literature, there are still discrepancies among the results. These may be due to the different GHG accounting methods, including those used by different Low-Carbon Policies (LCPs). To have a clearer understanding of the life cycle performance of AJF, the carbon footprint of ten pathways was estimated, comprising promising feedstocks – such as soybean, palm, sugarcane, sugarcane residues, forestry residues, used cooking oil, beef tallow, and steel off-gases – and ASTM-approved technologies: Hydroprocessed Fatty Acids, Alcohol-to-Jet, and Fischer-Tropsch. Six methodological approaches were used: the attributional and the consequential life cycle assessment, as well as guidelines for the four LCPs: Renovabio (Brazil), CORSIA (aviation sector), RFS (United States), and RED II (Europe). Soybean-based pathway (24 to 98.7 gCO2e/MJ) had the low to no potential for reducing GHG when compared to their fossil counterparts, mainly due to land use change. Of all food-based pathways, AJF produced from sugarcane performed the best (-10.4 to 43.7 gCO2e/MJ), especially when power surplus was credited. AJF from palm oil could present significant GHG reduction for palm expansion in degraded pasturelands. By contrast, Fischer-Tropsch of lignocellulosic residues showed the highest potential for reducing GHG (-95% to -130%). Different from food-based pathways, the potential GHG reduction of residues-based pathways converged within a narrower range (-130% to -50%), except when residual feedstocks have to be redirected from their current economic use. It could lead to GHG emissions higher than fossil fuel.

The carbon footprint of alternative jet fuels produced in Brazil: exploring different approaches

A corn crop is responsible for increasing the nutritional management function and for that reason, the work aimed to evaluate the influence of nitrogen (N) and zinc (Zn) in the production of the crop. The experiment was conducted in pots in the experimental area, in the city of Bebedouro. It was installed in random blocks, consisting of twenty-seven plots. The controls correspond to combinations of three doses of Zn (2, 8 and 16 kg ha-1), applied in a localized seeding manner and three of N (0, 120 and 240 kg ha-1) applied in partial sowing and in coverage. The productive characteristics were evaluated: number of rows and grains per ear and yield. The interaction between N and Zn provided by the use of 120 kg ha-1 of N and 2 kg ha-1 of Zn resulted in plants with higher yield (30.96 t ha-1). The application of N did not influence the number of rows per spike, while increasing doses of Zn did not provide better performance for this production component. The use of the highest dose of Zn (16 kg ha-1) had a negative influence on the amount of grains per ear, while the interaction between the doses of 120 kg ha-1 of N and 2 kg ha-1 of Zn represented the treatment. more efficient in this analysis. Doses greater than 2 kg ha-1 of Zn interact negatively together with doses of 0 and 120 kg ha-1 of N, for the variables grains per ear and productivity.

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Interação de nitrogênio e zinco na produção de milho

Intercropping improves land-use efficiency under conditions of limited land and resources, but no information is currently available pertaining to land-use efficiency and silage quality based on whole-plant utilization. Therefore, a two-year field experiment was conducted with the following conditions: three maize–soybean strip intercropping patterns, comprising two maize rows along with two, three, or four soybean rows (2M2S, 2M3S, and 2M4S, respectively); and two sole cropping patterns of maize (SM) and soybean (SS). The aim was to evaluate the biomass yield and silage quality under each condition. Our results showed that all SIPs had a land equivalent ratio (LER) of over 1.6 based on both fresh and dry matter yield, and a higher whole plant yield, compared to sole cropping. Specifically, 2M3S exhibited the highest whole crop dry matter LER (1.8–1.9) and yield (24.6–27.2 t ha−1) compared to SM and SS (20.88–21.49 and 3.48–4.79 t ha−1, respectively). Maize–soybean mixed silages also showed better fermentation quality with higher lactic acid content (1–3%) and lower ammonia-N content (2–8%) compared to SS silages, and higher crude protein content (1–1.5%) with lower ammonia-N content (1–2%) compared to SM silage. Among the intercropping patterns, 2M3S had the highest fermentation quality index V-score (92–95). Consequently, maize–soybean strip intercropping improved silage quality and biomass yield, with 2M3S being recommended, due to its highest LER and biomass yield, and most optimal silage quality.

/pdf/silage-quality-and-output-of-different-maize-soybean-strip-263gk5gj.pdf

Silage Quality and Output of Different Maize–Soybean Strip Intercropping Patterns

Intercropped maize-soybean silage: Effects on forage yield, fermentation pattern and nutritional composition

The corn and soybean intercropping can increase the quality of the silage and result in higher animal productivity. This research aimed to evaluate the agronomic aspects of intercropped corn + soybean, fermentative and bromatological profile of the intercropping silage, in function of the plant spatial arrangement, and types of fertilization. Two tests were performed; test 1: being in simple arrangement (a corn line alternated with a soybean line); test (2) in double arrangement (two corn lines alternated with a soybean line). The experimental design was a randomized block design in a 2x2 + 1 factorial scheme, with four replications. The first factor was constituted of two sowing fertilization modalities in the line: only in corn, and in total area; the second factor, were the seeding fertilization types: 100 and 70 kg ha-1 P2O5 and K2O, respectively (Dose 1) and 150 and 95 kg ha-1 of P2O5 and K2O, respectively (Dose 2). The additional treatment corresponded to corn monoculture. After harvesting, the material was ensiled for 60 days. There was no statistical difference in the yield of silage between treatments, only increases in the production of soybean pods and in the quality of the silage in the higher doses of fertilization. The results show that the soybean addition in corn silage causes greater losses during the fermentation process, but in contrast increases the protein and ether extract contents and digestibility. Pointing out that a roughage with these characteristics may supply protein supplementation in ruminant diets.

/pdf/perfil-agronomico-fermentativo-e-bromatologico-da-silagem-1pgb2o70ul.pdf

Perfil agronômico, fermentativo e bromatológico da silagem obtida do consórcio entre milho e soja

The success of maize + soybean intercrop depends on the plant arrangement. An experiment was carried out to evaluate different row arrangements on intercrop forage yield, silage quality and maize grain yield in relation to maize as a sole crop. The experiment was set up with a randomized complete block design with eight row arrangements between maize and Soybean. Maize biomass yield among crop arrangements were similar, although, lower than the maize sole crop. On the other hand, these treatments showed higher soybean biomass yield, which in turn increased silage crude protein and crude protein yield per unit area. Maize thousand grain weight, grain yield per plant and per area was affected by the intercrop arrangements. The use of two corn rows + two soybean rows (2M+2S-30 cm) and four corn rows + four soybean rows (4M+4S-30 cm) showed higher crude protein yield per area associated with similar maize grain yield in relation to the sole maize crop. In conclusion, alternating four maize rows with four soybean rows was the optimum row ratio in maize + soybean intercrop, though this needs to be further confirmed by more trials.

https://www.ccsenet.org/journal/index.php/jas/article/download/0/0/38103/38593

Row arrangements of maize and soybean intercrop on silage quality and grain yield.

Varios fatores interferem na produtividade da cultura do milho ( Zea mays L.), destacando-se densidade de plantas e dose de nitrogenio (N). Objetivou-se, com este estudo, avaliar a interferencia de densidades de plantas e doses de N, no cultivo de milho safrinha em Dois Vizinhos – PR. Foram avaliadas duas densidades de semeadura (45.000 e 55.000 plantas ha -1 ) e quatro doses de N (0, 50, 100 e 150 kg ha -1 ). Utilizou-se o delineamento em blocos ao acaso com parcelas subdivididas. A semeadura foi realizada em 15 de janeiro de 2015, utilizando o hibrido Dow AgroSciences 2B587Hx. As doses de N foram aplicadas em cobertura, quando as plantas estavam em estadio vegetativo V4. Foram avaliados os seguintes caracteres agronomicos: diâmetro do colmo, altura da primeira espiga, altura de planta, estande de plantas, quantidade de espigas, porcentagem de restolhos, fileiras por espiga, graos por fileira, massa de 1.000 graos e produtividade. Os dados foram submetidos a analise de variância, e, quando significativo, aplicou-se teste de media para as densidades e analise de regressao para as doses de N. Nao foi constatada interacao entre os fatores avaliados, porem o aumento da dose de N proporcionou acrescimo linear no diâmetro do colmo, altura de plantas, altura de insercao da espiga, massa de 1.000 graos e produtividade. A densidade de 55.000 plantas ha -1 resultou em menor diâmetro do colmo e numero de graos por fileira, mas apresentou estande de plantas superior, com maior quantidade de espigas e consequentemente, maior produtividade de graos, sendo adequada a cultura.

https://ojs.ufgd.edu.br/index.php/agrarian/article/download/7485/5338

Densidade de plantas e doses de nitrogênio no cultivo de milho safrinha no Paraná

O cultivo de soja em safrinha no Paraná foi restringido e o milho tende a ser cultivado em maior escala no Estado. O objetivo do estudo foi avaliar os componentes de rendimento do milho safrinha, manejado com diferentes níveis de adubação nitrogenada (0, 50, 100 e 150 kg ha-1) e com densidades de semeadura elevadas (65.000 e 75.000 sementes ha-1). O experimento foi conduzido em Dois Vizinhos (PR), durante a safrinha 2015, em sistema de plantio direto e foram avaliados os componentes de rendimento da cultura. Foram observados maiores valores de número de espigas por planta, número de grãos por fileira, número de grãos por espiga, produtividade por planta e por espiga na menor densidade. O número de grãos por espiga aumentou de forma linear com o acréscimo dos níveis de nitrogênio, porém as demais variáveis não foram influenciadas pelos níveis do nutriente. A massa de mil grãos e a produtividade do milho safrinha não sofreram influência dos fatores avaliados, porém com produtividade média de 10.113 kg ha-1, o cultivo de milho safrinha em Dois Vizinhos (PR) apresentou-se como satisfatório, mesmo sem aplicação de nitrogênio, sendo uma alternativa para os produtores.

Níveis de nitrogênio no cultivo de milho segunda safra com elevadas densidades de plantas

O cultivo com milho safrinha no sul do Brasil tem aumentado nos ultimos anos. Neste contexto, o objetivo do estudo e avaliar o rendimento de graos de hibridos de milho, cultivados em diferentes densidades e com distintos niveis de nitrogenio. O estudo foi conduzido no municipio de Dois Vizinhos – PR e utilizou-se delineamento de blocos ao acaso, em esquema fatorial (2x4x4), no qual o fator A, refere-se a hibridos de milho (2B587 e AG9030), o fator B: densidades de semeadura (45.000, 55.000, 65.000, 75.000 plantas ha-1), e o fator C: niveis de nitrogenio (0, 50, 100, 150 kg ha-1). O hibrido 2B587 apresentou maiores valores de populacao final, numero de espigas por area, numero de graos por fileira e produtividade, porem menor quantidade de fileiras por espiga e massa de mil graos em relacao ao hibrido AG9030. Observou-se resposta linear dos niveis de nitrogenio sobre a produtividade (9158 + 3,265x) porem sem viabilidade economica devido as boas condicoes de fertilidade do solo. O aumento da densidade de semeadura reduziu a prolificidade do milho. Os dois hibridos avaliados apresentam melhor resposta de produtividade nas densidades de 55.000 e 65.000 plantas por hectare.Palavras-chave: Zea mays, componentes de rendimento, produtividade. DENSITIES OF PLANTS AND NITROGEN LEVELS IN MAIZE HYBRID PERFORMANCE IN THE SECOND SUMMER CROP ABSTRACT: Maize grown as a second summer crop areas in southern Brazil has increased in recent years. In this context, the objective of the study was to evaluate the grain yield of maize hybrids grown at different plant densities and levels of nitrogen. The study was carried out at Dois Vizinhos (PR) in a randomized complete block design with a factorial scheme (2x4x4), being factor A referent to maize hybrids (2B587 and AG9030), factor B (45,000, 55,000, 65,000, 75,000 plants ha-1), and factor C: nitrogen levels (0, 50, 100, 150 kg ha-1). The hybrid 2B587 showed higher values of final plant population, number of spikes per area, number of grains per row and final yield, but smaller number of rows per spike and thousand grain weights in relation to the Hybrid AG9030. There was a linear response of nitrogen levels over maize yield (9,158 + 3.265x) was observed but without economic viability due to good soil fertility conditions. The increase of the sowing density reduced corn prolificacy. Both evaluated hybrids showed a better yield response at plant densities from 55,000 to 65,000 plants per hectare.Keywords: Zea mays, yield components, productivity.

https://periodicoscientificos.ufmt.br/ojs/index.php/nativa/article/download/6681/5389

Densidades de plantas e níveis de nitrogênio no desempenho de híbridos de milho em safrinha

Maize is one of the main cereals produced worldwide and, in association with soybean crop, can result in benefits to the production system. The objective of this study was to evaluate the biomass yield for silage and grain yield in maize crop, in the maize-soybean intercropping system. The study was conducted in the municipality of Dois Vizinhos - PR, Brazil, using a randomized block design, with nine treatments and four replicates. The treatments were composed of three maize hybrids grown in monoculture and in intercropping with two soybean cultivars (P1630+TMG7062, P1630+P95R51, P1630, LG6030+TMG7062, LG6030+P95R51, LG6030, P30F53+TMG7062, P30F53+P95R51 and P30F53). The data were subjected to analysis of variance and, when there was significance, Scott-Knott test was applied. Maize biomass yield for silage was approximately 4,000 kg ha-1 higher when the hybrids LG6030 and/or P30F53 were used. The cultivar TMG7062 stands out from P95R51 in terms of dry biomass yield for silage. The higher the percentage of soybean biomass added to the silage, the higher its crude protein content. However, crude protein yield per area was similar for the evaluated treatments. Some yield components (number of grains per row and thousand-grain weight) and grain yield of maize differ according to the hybrid used, but similarity is observed between intercropping and monoculture. There is evidence that the soybean cultivar TMG7062, intercropped with P1630, has the potential to reduce the grain yield of the cereal.

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Papers

Row arrangements of maize and soybean intercrop on silage quality and grain yield.

Densidade de plantas e doses de nitrogênio no cultivo de milho safrinha no Paraná

Níveis de nitrogênio no cultivo de milho segunda safra com elevadas densidades de plantas

Densidades de plantas e níveis de nitrogênio no desempenho de híbridos de milho em safrinha

Biomass yield for silage and grain yield of maize intercropped with soybean