Multidimensional analysis of carrot-lettuce intercroppings under different combinations of population densities

Este trabalho teve como objetivo avaliar o desempenho biológico de sistemas consorciados de cenoura e alface, sob diferentes combinações de densidades populacionais, com uso das análises bivariada de variância e envoltória de dados (DEA). O delineamento experimental usado foi o de blocos ao acaso completos, com cinco repetições, com os tratamentos arranjados em esquema fatorial 4x4. Os tratamentos resultaram da combinação de quatro populações de plantas de cenoura (40, 60, 80 e 100% da população recomendada no cultivo solteiro – PRCS) com quatro populações de plantas de alface (40, 60, 80 e 100% da PRCS). As populações recomendadas para os cultivos solteiros da cenoura e alface foram 500 mil e 250 mil plantas por hectare, respectivamente. Tanto o método bivariado como o método de análise de envoltória de dados são bastante eficazes na discriminação dos melhores sistemas de cultivo consorciados, por meio dos rendimentos das culturas. Os resultados da eficiência produtiva, medidos por modelos DEA, permitem uma análise estatística simples do ensaio consorciado. A robustez do método de análise bivariada de variância assegura a validade dos resultados.The objective of this paper was to evaluate the biological performance of carrot and lettuce intercropping systems under different combinations of population densities, using the bivariate analysis of variance and data envelopment analysis (DEA). The experimental design was the randomized complete blocks, in a 4x4 factorial scheme (carrot densities: 40, 60, 80 and 100% of the recommended sole crop density (RSCD); lettuce densities: 40, 60, 80 and 100% of the RSCD), with five replications. The recommended population density for carrot in sole crop is 500 thousand plants per hectare and for lettuce in sole crop is 250 thousand plants per hectare. Both bivariate method of variance and data envelopment analysis are quite effective in discriminating the best intercropping systems as assessed through component crop yields. The results of the yield efficiency as assessed by DEA models allow a simple statistical analysis of the intercropping experiment. The robustness of the bivariate analysis of variance method assures the validity of the results

Dose econômica de nitrogênio para fertirrigação da cultura do milho verde no semiárido brasileiro

The objective of this work was to determine the nitrogen rate for fertigation associated with the maximum productivity of green corn (Zea mays) with a lower production cost, in two harvest seasons in the Brazilian semiarid region. The experimental design was a randomized complete block with four replicates, and the treatments consisted of four N rates (0, 80, 160, and 240 kg ha-1) in form of urea, applied via drip irrigation. The used cultivar was the Bt Feroz hybrid. The evaluated characteristics were: number and mass of marketable ears, gross income, net income, and rate of return. The greatest amounts of marketable ears were reached with 152.52 kg ha-1 N in summer (41,183.84 ears per hectare) and 190.31 kg ha-1 N in winter (53,291.25 ears per hectare). In the two harvests, there was a variation in production costs between R$2,422.12 ha-1 and R$ 3,320.95 ha-1 without N and with 240 kg ha-1 N, respectively. The winter harvest showed higher productivity and profitability of green ears with fertigation with 160 kg ha-1 N. In the Brazilian semiarid, the maximum productivity of green corn with the lowest production cost is reached with fertigation with 90 kg ha-1 N, in both harvests.O objetivo deste trabalho foi determinar a dose de nitrogênio para fertirrigação associada à máxima produtividade de milho verde (Zea mays) com menor custo de produção, em duas safras agrícolas no semiárido brasileiro. O delineamento experimental foi em blocos ao acaso, com quatro repetições, e os tratamentos consistiram em doses de N (0, 80, 160 e 240 kg ha-1), na forma de ureia, via irrigação por gotejamento. A cultivar utilizada foi o híbrido Bt Feroz. As características avaliadas foram: número e massa de espigas comercializáveis, renda bruta, renda líquida e taxa de retorno. As maiores quantidades de espigas comercializáveis foram alcançadas com 152,52 kg ha-1 de N no verão (41.183,84 espigas por hectare) e 190,31 kg ha-1 de N no inverno (53.291,25 espigas por hectare). Nas duas safras, houve variação nos custos de produção entre R$2.422,12 ha-1 e R$ 3.320,95 ha-1 sem N e com 240 kg ha-1 de N, respectivamente. A safra de inverno apresentou maior produtividade e rentabilidade de espigas verdes com fertirrigação com 160 kg ha-1 de N. No semiárido brasileiro, a máxima produtividade de milho verde com menor custo de produção é alcançada com a fertirrigação com 90 kg ha-1 de N, em ambas as colheitas

Produtividade de cultivares de alface em função da idade de colheita no semiárido Potiguar, Brasil

No Nordeste brasileiro, o cultivo da alface restringe-se a pequenas áreas, com a utilização de cultivares pouco adaptadas às condições climáticas da região, dessa forma, ocorre o florescimento precoce e baixa produtividade. Diante disso, a pesquisa foi realizada objetivando-se avaliar as respostas agronômicas de cultivares de alface em função da idade de colheita, quando cultivadas em condições semiáridas. O experimento foi conduzido em campo, entre os meses de outubro de 2013 e janeiro de 2014, em Mossoró, Rio Grande do Norte. O delineamento experimental foi em blocos casualizados, arranjados em parcelas subdivididas, com quatro repetições. As parcelas consistiram em cinco idades de colheita (20, 25, 30, 35 e 40 dias após o transplantio – DAT), enquanto as subparcelas corresponderam a seis cultivares de alface dos grupos: Lisa (Babá de Verão, Lívia e Aurélia) e Crespa (Jullie, Elba e Maravilha 4 Estações). Foram avaliadas as características: altura e diâmetro de plantas, número de folhas por planta, produtividades total e comercial, e massa seca da parte aérea. A cultivar Babá de Verão é a mais produtiva dentre as cultivares de alface do grupo Lisa e a Jullie dentre as Crespas. A cultivar de alface Aurélia, do grupo Lisa, é a menos produtiva em relação as demais estudadas. A idade de colheita ideal à máxima produtividade comercial foi aos 30 DAT para todas as cultivares de alface

Nutrient uptake in sesame cultivars under cultivation in semiarid conditions

Sesame is considered the oldest oleaginous seed in use by mankind. It is a culture of high morphophysiological complexity with great variability in growth habit. The accumulation of nutrients in the sesame crop is, in relative terms, proportional to its average productivity. It is a crop that requires the availability of sufficient amounts of nitrogen, phosphorus and potassium to obtain a desired yield. Thus, the aim of this study was to assess the uptake of nutrients for sesame cultivars in two growing seasons conditions semiarid. The experiments were performed in Horta Didatics of Universidade Federal Rural do Semi-Ãrido, in Brazil, from November 2014 to February 2015 (Growing Season I); and from April to July 2015 (Growing Season II). The experimental design was a randomized complete block design with four replications. Treatments were arranged in a split plot where cultivars (CNPA G2, CNPA G3, and CNPA G4) were placed on the following plots with harvesting dates 21, 35, 49, 63, 77, 91, and 105 days after sowing (DAS) of subplots. The vegetative part of the sesame crop had greater uptake of potassium in Growing Season I (the period from November 2014 to February 2015) and of nitrogen in Growing Season II (the period from April to July 2015) for all the cultivars, whereas in the fruits the greatest uptake was that of nitrogen, independent of growing season. As for the total uptake of nutrients at the end of the cycle, it followed the descending order N > K > P in both growing seasons. The period of greatest demand for nutrients occurred between 77 and 105 DAS. In relation to the cultivars, the CNPA G3 obtained larger uptakes in Growing Season I (the period from November 2014 to February 2015), while the CNPA G4 did so in Growing Season II (the period from November 2014 to February 2015)

Production of Sunflower Oil in Response to Nitrogen Fertilization under Semiarid Conditions under Irrigation

Sunflower is one of the most important oilseeds in the world, whose achenes are valued in several industrial chains, mainly for the extraction and processing of its oil. Although there is some information in the literature, the nitrogen (N) requirements for sunflower in semiarid conditions under irrigation are not yet clear. The experimental design used randomized blocks, with treatments in subdivided plots with four replications during two agricultural seasons. The N doses (e.g., 0, 30, 60, 90 and 120 kg ha-1) were assigned to the plots, and to the four sunflower cultivars used (e.g., Aguará 06, Altis 99, Multissol and BRS 122), which were planted in the subplots. The N doses for the maximum achene yields for the Multissol and BRS 122 cultivars were 81.8 and 86.6 kg ha-1, respectively, while N doses of 120 kg ha-1 produced the maximum achene yields for the Altis 99 and Aguará 06 cultivars in the 2016 crop season. In 2017, the Multissol and BRS 122 cultivars were given N doses of 100.7 and 92.8 kg ha-1, respectively, and the Altis 99 and Aguará 06 cultivars were each given an N dose of 120 kg ha-1 of N. The fertirrigated doses of maximum economic efficiency of N were 60 and 70 kg ha-1 for the Multissol and BRS 122 cultivars, respectively. For the oil yields, the maximum N doses of 78.0 and 86.7 kg ha-1 for the BRS 122 and Aguará 06 cultivars and for the Multissol and Altis 99 cultivars at an N dose of 120 kg ha-1 were used for the 2016 harvest. In 2017, the BRS 122 and Multissol cultivars received N doses of 88.6 and 99.1 kg ha-1, respectively, and the Altis 99 and Aguará 06 cultivars received N doses of 120 kg ha-1. The use of fertigation allowed greater efficiency for the N doses in the sunflower cultivars in the semiarid region

Agro-economic viability from two croppings of broadleaf vegetables intercropped with beet fertilized with roostertree in different population densities

The objective of this study was to evaluate the sustainability and agro-economic viability from two croppings of coriander (C) and two of arugula (A) intercropped with beet (B) as a function of roostertree amounts added to the soil in different population densities. The experimental design was a randomized complete block, with treatments arranged in a 4 x 4 factorial scheme with four replications. The treatments resulted from the combination of four amounts of roostertree biomass (6, 19, 32 and 45 t ha-1 on dry basis) with four population densities of coriander, beet and arugula (20C-50B-20A%, 30C-50B-30A%, 40C-50B-40A% and 50C-50B-50A% of the recommended densities in their single crops). The maximum agronomic efficiency of the polyculture of coriander, beet and arugula was obtained with the density of 40C-50B-40A in the amount of 19 t ha-1 roostertree biomass incorporated into the soil. The highest profitability of the polyculture was obtained with the density of 20C-50B-20A (%) in the amount of 45 t ha-1 of this green manure. High agro-economic efficiency can be obtained by cultivating the polyculture of coriander, beet and arugula when well-managed the factors of production, fertilization with roostertree and population densities. Highlights There are agro-economic efficiency and sustainability in the polyculture of coriander-beet-arugula. Population density is an important production factor for obtaining of agro-economic returns. Appropriate management in the coriander-beet-arugula fertilization with roostertree can provide economic revenues.The objective of this study was to evaluate the sustainability and agro-economic viability from two croppings of coriander (C) and two of arugula (A) intercropped with beet (B) as a function of roostertree amounts added to the soil in different population densities. The experimental design was a randomized complete block, with treatments arranged in a 4 x 4 factorial scheme with four replications. The treatments resulted from the combination of four amounts of roostertree biomass (6, 19, 32 and 45 t ha-1 on dry basis) with four population densities of coriander, beet and arugula (20C-50B-20A%, 30C-50B-30A%, 40C-50B-40A% and 50C-50B-50A% of the recommended densities in their single crops). The maximum agronomic efficiency of the polyculture of coriander, beet and arugula was obtained with the density of 40C-50B-40A in the amount of 19 t ha-1 roostertree biomass incorporated into the soil. The highest profitability of the polyculture was obtained with the density of 20C-50B-20A (%) in the amount of 45 t ha-1 of this green manure. High agro-economic efficiency can be obtained by cultivating the polyculture of coriander, beet and arugula when well-managed the factors of production, fertilization with roostertree and population densities. Highlights There are agro-economic efficiency and sustainability in the polyculture of coriander-beet-arugula. Population density is an important production factor for obtaining of agro-economic returns. Appropriate management in the coriander-beet-arugula fertilization with roostertree can provide economic revenues

Effectivity and selectivity of herbicides applied in pre-emergence in the sesame (Sesamum indicum L.) crop

Weed control in the sesame crop (Sesamum indicum L.) is a fundamental practice that ensures high grain yield. Choosing adequate control methods is a crucial step to reduce costs and reach success in weed management. Among these methods, application of chemicals shows high efficiency and low cost for farmers. However, the use of this method in sesame crops is limited because there is a restricted number of herbicides registered for pre- and post-emergence applications. Considering the importance of chemical methods for weed management, the objective of this research was to select herbicides to be applied in pre-emergence that could be used to control weeds in the sesame crop. Two experiments were carried out, one to determine the efficiency and another to determine the selectivity of herbicides applied in pre emergence. The experiments were performed in a randomized complete block design (CBD) with four replicates. The treatments consisted of seven herbicides, a mixture of herbicides applied in pre-emergence, and two control treatments, one weed-free and one with weeds. Diuron and flumioxazin were found to be selective for pre-emergence. Metribuzin exhibited high toxicity to sesame, but it was effective to control several weed species, and metolachlor did not provoke high phytotoxicity in sesame, but reduced yield. Highlights: The control of weeds in the sesame crop is a fundamental practice for the productivity of this oilseed. The chemical method applied is the most used due to its high efficiency and low cost. Few herbicides applied in preemergence are registered for sesame cultivation. The selectivity and efficiency of 8 herbicides applied pre-emergence in sesame was studied. The herbicides Diuron and flumioxazin were selective for the cultivation of sesame and efficient in the control of weeds.Weed control in the sesame crop (Sesamum indicum L.) is a fundamental practice that ensures high grain yield. Choosing adequate control methods is a crucial step to reduce costs and reach success in weed management. Among these methods, application of chemicals shows high efficiency and low cost for farmers. However, the use of this method in sesame crops is limited because there is a restricted number of herbicides registered for pre- and post-emergence applications. Considering the importance of chemical methods for weed management, the objective of this research was to select herbicides to be applied in pre-emergence that could be used to control weeds in the sesame crop. Two experiments were carried out, one to determine the efficiency and another to determine the selectivity of herbicides applied in pre emergence. The experiments were performed in a randomized complete block design (CBD) with four replicates. The treatments consisted of seven herbicides, a mixture of herbicides applied in pre-emergence, and two control treatments, one weed-free and one with weeds. Diuron and flumioxazin were found to be selective for pre-emergence. Metribuzin exhibited high toxicity to sesame, but it was effective to control several weed species, and metolachlor did not provoke high phytotoxicity in sesame, but reduced yield. Highlights: The control of weeds in the sesame crop is a fundamental practice for the productivity of this oilseed. The chemical method applied is the most used due to its high efficiency and low cost. Few herbicides applied in preemergence are registered for sesame cultivation. The selectivity and efficiency of 8 herbicides applied pre-emergence in sesame was studied. The herbicides Diuron and flumioxazin were selective for the cultivation of sesame and efficient in the control of weeds

Indirect selection for content of carotenoid in pumpkin accessions

Carotenoid quantification in foods can be performed by various techniques, such as spectrophotometry, mass spectrometry, high performance liquid chromatography, gas chromatography and colorimetry. The objective of this study was to verify the feasibility of indirect selection of total carotenoids in pumpkin accessions. The experimental design was in complete randomized blocks with two replications and three plants per plot. The treatments consisted of 51 Cucubita moschata Duch accessions from the DCAF/UFERSA Cucurbitaceae germplasm collection and a commercial C. maxima Duch cultivar. After maturation, the fruits were harvested and colorimetric and total carotenoid contents were evaluated. Pulp color intensity parameters and hº angle indicated the possibility of indirect selection of accessions with higher total carotenoid contents. The ABO22 access presented higher total carotenoid content under the evaluation conditions of the experiment. Highlights There is variability in the total carotenoid content in pumpkin accessions. The pumpkin accessions studied have potential for food biofortification. Feasibility of indirect selection in pumpkin accessions for high total carotenoid content.Carotenoid quantification in foods can be performed by various techniques, such as spectrophotometry, mass spectrometry, high performance liquid chromatography, gas chromatography and colorimetry. The objective of this study was to verify the feasibility of indirect selection of total carotenoids in pumpkin accessions. The experimental design was in complete randomized blocks with two replications and three plants per plot. The treatments consisted of 51 Cucubita moschata Duch accessions from the DCAF/UFERSA Cucurbitaceae germplasm collection and a commercial C. maxima Duch cultivar. After maturation, the fruits were harvested and colorimetric and total carotenoid contents were evaluated. Pulp color intensity parameters and hº angle indicated the possibility of indirect selection of accessions with higher total carotenoid contents. The ABO22 access presented higher total carotenoid content under the evaluation conditions of the experiment. Highlights There is variability in the total carotenoid content in pumpkin accessions. The pumpkin accessions studied have potential for food biofortification. Feasibility of indirect selection in pumpkin accessions for high total carotenoid content

Eficiência agroeconômica de sistemas consorciados de feijão-caupi verde e rabanete em ambiente semiárido

The objective of this work was to evaluate the agro-economic efficiency of immature cowpea-radish intercropping systems in a semiarid environment in Brazil. The experiments were carried out in two cropping seasons, in a randomized complete block design with four replicates. The treatments consisted of a 4x2 factorial arrangement for the combination of four cowpea (Vigna unguiculata) cultivars (BRS Tumucumaque, BRS Cauamé, BRS Guariba, and BRS Itaim) and two radish (Raphanus sativus) cultivars (Crimson Gigante and Zapp). The agro-economic indices – system productivity index (SPI), land equivalent coefficient (LEC), and monetary equivalent ratio (MER) – were obtained using single plots of each cultivar in each block. 'BRS Tumucumaque' and 'BRS Guariba' showed the highest productivity of immature cowpea pods, and 'Crimson Gigante' showed the highest yield of marketable radish roots. The cultivation of either 'BRS Tumucumaque' or 'BRS Guariba' cowpea with 'Crimson Gigante' radish provides a greater agro-economy efficiency and sustainability for immature cowpea-radish intercropping.O objetivo deste trabalho foi avaliar a eficiência agroeconômica de sistemas consorciados de feijão-caupi verde e rabanete, em ambiente semiárido brasileiro. Os experimentos foram realizados em duas safras agrícolas, em delineamento de blocos ao acaso, com quatro repetições. Os tratamentos consistiram de um arranjo fatorial 4x2, para a combinação de quatro cultivares de feijão-caupi (Vigna unguiculata) (BRS Tumucumaque, BRS Cauamé, BRS Guariba e BRS Itaim) com duas cultivares de rabanete (Raphanus sativus) (Crimson Gigante e Zapp). Os índices agroeconômicos ‒ índice de produtividade do sistema (IPS), coeficiente equivalente de terra (CET) e razão equivalente monetária (REM) ‒ foram obtidos em parcelas de cultivo solteiro de cada cultivar, em cada bloco. 'BRS Tumucumaque' e 'BRS Guariba' apresentaram a maior produtividade de vagens verdes de feijão-caupi, e 'Crimson Gigante' mostrou a maior produtividade de raízes comerciais de rabanete. O cultivo do feijão-caupi 'BRS Tumucumaque' ou 'BRS Guariba' com o rabanete 'Crimson Gigante' proporciona maior eficiência agroeconômica e sustentabilidade ao consórcio de feijão-caupi verde com rabanete

Agro-economic profitability of sweet potato cultivars as a function of the harvest age and times of cultivation in the semi-arid

The objective of this work was to evaluate the profitability of sweet potato cultivars, harvested at different ages and cultivated in different periods (rainy and dry) in the municipality of Mossoró, semi-arid region of Rio Grande do Norte. The experimental design was a randomized complete block design with four replications and treatments arranged in split plots scheme. The plots were composed of three sweet potato cultivars (ESAM 1, Paraná and Mother of Family) and the subplots for five harvest ages (90 , 105, 120, 135 and 150 days after transplanting - DAT). Productivity of commercial roots and production costs was evaluated, as well as the economic indicators: gross income, net income, rate of return and profit margin. Independently of the growing periods, the productivity of commercial roots increased with the later harvest of the crop and differentiated the cultivars. Production costs averaged R$6,087.97 ha-1 in the rainy season and R$ 6,181.42 ha-1 in the dry period. Labor expenditures were the most impacting of total expenditures. The cultivars ESAM 1 and Paraná presented higher productivities of commercial roots and profitability when cultivated in the rainy season, while Paraná cultivar was superior to the other cultivars in the crop in the dry season. In both growing periods, the harvest age of 150 DAT promoted higher productivities of commercial roots and profitability to sweet potato production