Leaf nutrient content and yield of tomato grown in different substrates and doses of humic acidsWe evaluated the nutritional status and yield of tomato hybrid "Vênus", grown on substrates, with application of humic acids (AH) and fertigation. Four doses of AH (0, 20, 40 and 80 L -1 ha) and four substrates: S1 (coconut fiber (CF)), S2 (FC + carbonized coffee husk (CC) in the ratio 1:3), S3 (CF + CC -in the ratio 2:3) and S4 (CC) were evaluated following the randomized blocks design in factorial 4x4 scheme with four replications. The 35-day old seedlings were transplanted into plastic bags of 7 L. The humic acids were applied four times in eight-day intervals, and the first application was carried out eight days after transplanting. There was no significant effect of the treatments on the content of N, K and S in leaves and on nonmarketable fruits yield. However, there was a significant effect of the substrates on the content of P, Ca, Mg and on the total and marketable fruit yield. Increasing doses of AH reduced linearly the content of B and Cu (on S1), but increased the content of Zn in leaves. Humic acid doses of 31 to 49 L ha -1 provided the highest contents of Fe, Cu, and the lowest content of Mn. The highest marketable yields were obtained using coconut fiber, with an average of 5.6 kg/plant, showing an average yield increase of 22.9%, 38.7% and 49.7% in comparison to S2, S3 and S4, respectively.

RESUMOConduziu-se este trabalho, com o objetivo de avaliar o efeito da aplicação, via foliar, de diferentes doses de silicato de potássio, sob os teores de clorofila a, b e total em folhas de tomateiro cultivados em dois substratos e a influência desses fatores na produtividade da cultura sob ambiente protegido. O delineamento experimental foi de blocos ao acaso, em esquema fatorial 2 x 4, com quatro repetições. Foram utilizados os substratos fibra de coco (S1) e fibra de coco acrescido de casca de café carbonizada (S2). As doses de silicato de potássio foram 0; 0,1; 0,2 e 0,4 % do produto Sili-K ® . As doses do produto foram aplicadas semanalmente nas folhas das plantas, durante o ciclo da cultura. Antes da primeira colheita de frutos, quantificaram-se os teores de clorofila a, b e total, que apresentaram diferenças significativas apenas para S1. O aumento das doses de silicato de potássio aplicadas estimulou, de forma linear, a concentração de clorofila a, b e total em folhas de tomateiros. A massa média de frutos com diâmetro de 60 a 65 mm cultivados em S2 foi influenciada pelas diferentes doses de silicato de potássio. A dose 0,2% foi significativamente superior às concentrações testadas.Termos para indexação: Fibra de coco, casca de café carbonizada, cultivo em vasos, clorofila. ABSTRACTThis study was to evaluate the effect of leaf application of different doses of potassium silicate, on the levels of chlorophyll a, b and total in leaves of tomato cultivated in two substrates as well as the influence of these factors on crop yield under protected environment. The used experimental design was randomized blocks with four replicates. A factorial scheme 2 x 4 was used. The substrates were coconut fiber (S1) and coconut fibercombined with carbonized coffee husk (S2). The Used doses of potassium silicate were 0, 0.1, 0.2 and 0.4 % of Sili-K ® . These doses were sprayed weekly on the leaves during the dant cycle. Before the first harvest, chlorophylls a, b and total. that present significative differences only for S1 were quantified. The increase of potassium silicate doses stimulated the concentration of chlorophyll a, b and total chlorophyll. The average mass of fruits with 60 to 65 mm, diameter cultivated in S2 was influenced by the different doses of potassium silicate. The dose of 0.2% was the best concentration.

<p>Objetivou-se avaliar o efeito da inoculação de <em>Azospirillum brasilense </em>(AzBr) com e sem enraizador, no crescimento, produção de biomassa e resistência a pragas da alface, cultivar Lucy Brown. O experimento foi conduzido em casa de vegetação em recipientes plásticos com capacidade de 8,0 L no espaçamento 40 x 20 cm. O delineamento experimental foi de blocos casualizados em esquema fatorial (2x3)+1, sendo o primeiro fator <em>Azospirillum</em> com e sem enraizador de crescimento e o segundo doses de nitrogênio em cobertura, 0%, 50% e 100% da recomendação de adubação e uma testemunha com adubação convencional, com quatro repetições. Em doses médias de 50% de N em cobertura, tanto o AzBr, quanto a associação AzBr mais enraizador, apresentaram um incremento significativo na massa fresca da parte aérea e de raízes de 19,36% e 23,66%, respectivamente, em relação a dose máxima de N e a testemunha. A massa seca da parte aérea não diferiu significativamente nos diferentes tratamentos, embora tenha mostrado um pequeno aumento com as doses crescente de N. A massa seca de raízes diminuiu 29,24% no tratamento com 100% de N, quando comparado ao tratamento sem cobertura nitrogenada mais AzBr. O estande final de plantas foi significativamente maior no tratamento no qual N não foi aplicado em cobertura, destacando-se a inoculação com AzBr, média de 96,98% de plantas estabelecidas, contra 51,56% na testemunha convencional, observando-se que até a dose média de N, houve uma maior tolerância das plantas aos sintomas de minas foliares e as viroses do Grupo Tospovirus.</p><p align="center"><em>Azospirillum</em> <em>brasilense <strong>inoculation efficiency associated with rooting growth and production of lettuce</strong></em></p><p><strong>Abstract: </strong>In the survey evaluated the effect of <em>Azospirillum brasilense </em>(AzBr) inoculated with and without rooting, on growth, biomass production and lettuce pest resistance, cultivar Lucy Brown. The experiment was conducted in a greenhouse in plastic bags with 8.0 L capacity in the spacing, 40 x 20 cm. The experimental followed a design randomized blocks in a factorial scheme (2x3) +1, the first factor, <em>Azospirillum </em>with and without rooting growth and second fator, levels of nitrogen in coverage, 0%, 50% and 100% of fertilizer recommendation and a control with conventional fertilization, with four replications.  At mean doses of 50% N in coverage, both AzBr and the AzBr plus rooting association showed a significant increase in fresh shoot and root mass of 19.36% and 23.66%, respectively, in relation to maximum dose of N and the control. The shoot dry mass did not differ significantly in the different treatments, although it has shown a small increase with increasing doses of N. The dry root mass decreased 29.24% in the treatment with 100% N, when compared to treatment without nitrogen cover more AzBr.  The final plant stand was significantly higher in the treatment in wich N was not applied in coverage, especially inoculation with AzBr, mean of 96.98% of established plants, against 51.56% in conventional control, observing that average dose of N, there was a greater tolerance of plants to symptoms of leaf mining and the viruses of Tospovirus Group.</p>

The aim of this work was to evaluate the yield and quality of tomato fruits, hybrid "Vênus", produced on substrates and with application of nutrient solution and humic acids (AH). Four doses of AH were evaluated (0, 20, 40 and 80 L ha-1) and 4 substrates: S1 (coconut fiber (CF)), S2 (FC + carbonized coffee husk (CC) in the ratio 1:3), S3 (CF + CC in the ratio 2:3) and S4 (CC), were evaluated following the randomized blocks design in factorial 4x4 scheme with four replications. The 35-day old seedlings were transplanted into plastic bags of 7 L. The humic acids were applied four times in eight-day intervals, and the first application was carried out eight days after transplanting. There was no significant effect of AH on the yield and quality of fruit, except in relation to soluble solids (SS)/titratable acidity (AT). Doses of up to 36 L ha-1, increase the AT, above that amount favored increase of SS. The carbonized coffee husk in treatments S2, S3 and S4, did not alter the production of small fruits, medium, non-commercial, moisture, pH, SS, AT and SS/AT, however, significantly reduced the total production, commercial and large size fruit. The production of fruits in S1 was significantly higher compared to the other treatments, with an average of 142.6 t ha-1, showing average increase in yield of 24.4%, 29.3% and 36.1% compared to plant of treatments S2, S3 and S4, respectively.

Resumo. Este trabalho foi conduzido em condições de campo, com o objetivo de avaliar o desenvolvimento e a produtividade da cebola cv. Crioula submetida a diferentes doses de composto orgânico e níveis de adubação NPK. As mudas foram transplantadas em canteiros, com delineamento experimental em blocos casualizados, fatorial 4x2, sendo o primeiro tratamento constituído de doses de composto orgânico (0, 3, 6 e 9 L m −2 ) e o segundo, de níveis de fertilizantes minerais (N-5 e N-9, correspondentes a 50% e 90%, respectivamente, da recomendação da adubação de N, P 2 O 5 e K 2 O), com quatro repetições. A colheita ocorreu 131 dias após a semeadura e a produtividade máxima de bulbos comercializáveis foi de 4,77 kg m −2 . O número de plantas que não bulbificaram diminuiu com o aumento das doses de composto em até 43,5%, quando foi aplicado o tratamento N-9 e de 15,4% para N-5, da dose de NPK recomendada para a cebola. Doses crescentes de compostos orgânicos aumentaram a produção de bulbos podres, correspondendo a 21,43% para N-5 na dose de 9,0 L m −2 e em 18,12% para N-9 na dose estimada de 4,7 L m −2 . Não houve efeito dos tratamentos na produção de bulbos com diâmetro inferior a 35 mm, média de 0,59 kg m −2 , no estande final e no número de plantas com doenças foliares. A cv. Crioula pode ser recomendada para plantio, nas condições desse experimento de clima tropical úmido e solos de baixa fertilidade, desde que sejam feitas as devidas correções e adubações preconizadas para a cultura. Palavras-chaves: Allium cepa L. Adubos orgânicos. Fertilizantes minerais.Abstract. This work was carried out under field conditions, with the aim of evaluate the growth and yield of onion cv. Crioula exposed to different concentrations of organic compound and NPK fertilizer levels. The seedlings were transplanted on seedbeds beds, with a randomized block design factorial 4x2, with the first treatment consists of doses of organic compost (0, 3, 6 and 9 L m −2 ) and the second mineral fertilizer levels ( N-5 and N-9, corresponding to 50% and 90%, respectively, of the recommendation of fertilizers N, P 2 O 5 and K 2 O), with four replications. The harvest took place 131 days after sowing and the maximum yield of marketable bulbs was 4.77 kg m −2 . The number of plants that do not bulbing decreased with increasing doses of the compound up to 43.5% when the treatment N-9 was applied and 15.4% for N-5, of NPK dose recommended for onion. Increasing doses of organic compounds increased the production of rotten bulbs, corresponding to 21.43% for N-5 at a dose of 9.0 L m −2 and 18.12% for N-9 an estimated dose of 4.7 L m −2 . There was no effect of the treatments in the production of bulbs with a diameter less than 35 mm, average of 0.59 kg m −2 , in the final stand and the number of plants with leaf diseases. The cv. Crioula can be recommended for planting in the conditions of humid tropical climate this experiment and low fertility soils, provided they are made the recommended corrections and fertilizers for culture.

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Beans are nutrient-demanding plants, with a high demand for nitrogen (N). Nitrogen biological fixation (NBF) is probably the best solution to meet this demand, especially considering losses in the soil-plant-atmosphere system. Molybdenum (Mo), present in the enzymes nitrogenase and nitrate reductase, is fundamental in the metabolism of N, including NBF. This study aims to evaluate if bean seed inoculation with Azospirillum brasilense, Rhizobium tropici, and possible interactions with nitrogen topdressing and molybdenum leaf application, may affect winter bean development and yield. A randomized complete block design was used in a 4x2x2 factorial scheme. Plant population, production components, and grain yield were evaluated in two crop seasons (2017 and 2018). Seed inoculation with A. brasilense, when associated with 30 kg ha-1 N topdressing, increased plant population, pod number per plant and grain yield. Nitrogen topdressing is key to increasing winter bean productivity, regardless of inoculation or Mo foliar application.