| Name: | Description: | Size: | Format: | |
|---|---|---|---|---|
| 1.63 MB | Adobe PDF |
Authors
Advisor(s)
Abstract(s)
Há uma forte pressão global para uma solução às externalidades
negativas causadas pela agricultura convencional. Diante da situação, a
agricultura biológica vem se difundindo mundialmente como resposta para a
sustentabilidade rural, e os bisestimulantes como uma ferramenta sustentável,
na estratégia de eliminar e/ou reduzir o usos de produtos químicos. Existem
atualmente inúmeros produtos bioestimulantes comerciais diponíveis no
mercado, porém o modo de ação de muitos desses ainda são desconhecidos,
dado que estes produtos se divergem nos seus resultados de acordo com a
interação entre bioestimulantes, planta e meio ambiente. Com a finalidade de
ampliar o conhecimento das substâncias bioestimulantes comerciais, este
estudo tem como objetivo avaliar a produção e a exportação de nutrientes pela
alface (Lactuca sativa L.) sujeita a adubação com bioestimulantes ao solo e por
via foliar. Para o experimento foram testados 2 bioestimulantes comerciais, um
a base de leonardita (Humitec®) aplicado no solo antes do plantio, e outro de
extrato de algas (Fitoalgas Green®) aplicado via foliar durante a estação de
crescimento. Como fonte de nutrientes foram utilizados um fertilizante orgânico
comercial (Nutrimais®) e um fertilizante mineral (Nutri27, com 27% de nitrogênio,
50% de NH4+ e 50% de NO3
-). Estes fertilizantes foram utilizados em duas doses
diferentes (40 e 80 kg N ha-1), distinguindo-se como: Nutri40, Nutri80
(Nutrimais®), Min40 e Min80 (NH4NO3) que correspondem às respectivas
quantidades utilizadas por hectare. Foi também usado um tratamento controle
sem aplicação de bioestimulantes ou fertilizantes orgânicos ou minerais. O
delineamento foi organizado de forma completamente casualizada com 15
tratamentos e 3 repetiçõe, totalizando 45 vasos experimentais. Os resultados
foram submetidos à análise de variância e ao teste de comparação de médias
Tukey HSD (α<0,05). Os resultados foram favoráveis à produção vegetal e à
exportação de N nos tratamentos que receberam fertilizante mineral. O
fertilizante orgânico liberou pouco nitrogênio e os bioestimulantes tiveram efeito
reduzido no crescimento das plantas.
There is strong global pressure for a solution to the negative externalities caused by conventional agriculture. In view of this situation, organic farming has been spreading worldwide as a response to rural sustainability, and biostimulants as a sustainable tool in the strategy of eliminating and/or reducing the use of chemical products. There are currently numerous commercial biostimulant products available on the market, but the mode of action of many of these is still unknown, given that these products differ in their results according to the interaction between biostimulants, plant and environment. In order to increase knowledge of commercial biostimulant substances, this study aims to evaluate the production and export of nutrients by lettuce (Lactuca sativa L.) subjected to fertilization with biostimulants in the soil and via foliar application. For the experiment, two commercial biostimulants were tested, one based on leonardite (Humitec®) applied to the soil before planting, and another based on seaweed extract (Fitoalgas Green®) applied via foliar application during the growing season. A commercial organic fertilizer (Nutrimais®) and a mineral fertilizer (Nutri27, with 27% nitrogen, 50% NH4+ and 50% NO3 -) were used as nutrient sources. These fertilizers were used in two different doses (40 and 80 kg N ha-1), distinguished as: Nutri40, Nutri80 (Nutrimais®), Min40 and Min80 (NH4NO3), which correspond to the respective amounts used per hectare. A control treatment without application of biostimulants or organic or mineral fertilizers was also used. The design was organized in a completely randomized manner with 15 treatments and 3 replicates, totaling 45 experimental pots. The results were submitted to analysis of variance and the Tukey HSD test for comparison of means (α<0.05). The results were favorable to plant production and N export in the treatments that received mineral fertilizer. The organic fertilizer released little nitrogen and the biostimulants had a reduced effect on plant growth.
There is strong global pressure for a solution to the negative externalities caused by conventional agriculture. In view of this situation, organic farming has been spreading worldwide as a response to rural sustainability, and biostimulants as a sustainable tool in the strategy of eliminating and/or reducing the use of chemical products. There are currently numerous commercial biostimulant products available on the market, but the mode of action of many of these is still unknown, given that these products differ in their results according to the interaction between biostimulants, plant and environment. In order to increase knowledge of commercial biostimulant substances, this study aims to evaluate the production and export of nutrients by lettuce (Lactuca sativa L.) subjected to fertilization with biostimulants in the soil and via foliar application. For the experiment, two commercial biostimulants were tested, one based on leonardite (Humitec®) applied to the soil before planting, and another based on seaweed extract (Fitoalgas Green®) applied via foliar application during the growing season. A commercial organic fertilizer (Nutrimais®) and a mineral fertilizer (Nutri27, with 27% nitrogen, 50% NH4+ and 50% NO3 -) were used as nutrient sources. These fertilizers were used in two different doses (40 and 80 kg N ha-1), distinguished as: Nutri40, Nutri80 (Nutrimais®), Min40 and Min80 (NH4NO3), which correspond to the respective amounts used per hectare. A control treatment without application of biostimulants or organic or mineral fertilizers was also used. The design was organized in a completely randomized manner with 15 treatments and 3 replicates, totaling 45 experimental pots. The results were submitted to analysis of variance and the Tukey HSD test for comparison of means (α<0.05). The results were favorable to plant production and N export in the treatments that received mineral fertilizer. The organic fertilizer released little nitrogen and the biostimulants had a reduced effect on plant growth.
Description
Keywords
Agricultura convencional Alterações climáticas Sustentável Agricultura biológica Bioestimulantes Produção