Eficiência Nutricional e Produtividade de Milho pelo Uso de Biofertilizante Orgânico

O objetivo deste trabalho foi avaliar a influência do bioestimulante Fert Bokashi Premium® e microfiltrado sobre a eficiência nutricional e produtividade da cultivar de milho DKB 290 Pro3, em condições de campo. O delineamento experimental foi o de blocos ao acaso com onze tratamentos e quatro repetições. Os resultados indicaram ganhos nutricionais que influenciaram a produtividade de grãos, nas diferentes épocas de aplicação, plantio e foliar. Dessa forma, ficou clara a influência do produto Fert Bokashi® ativado na semeadura já que as médias foram superiores quando as aplicações ocorreram na semeadura e nos estádios vegetativos V4 e V8. Para o microfiltrado, foi obervado que os nutrientes Fe, Cu, K e S, mantiveram os níveis exigidos para a cultura, indicando que para incrementar a produtividade é necessário um aporte de nutrientes que garantem as plantas suas necessidades, e que a produtividade apresenta estreita relação com as taxas de nutrientes extraídas pelas plantas. O uso do biofertilizante Fert Bokashi® ativado aumenta os teores de Fe, K e S, os quais interferem na produtividade de milho em condições de campo, e quando aplicado no plantio e nos estádios V4 e V8. Palavras-chave: Fert Bokashi. Fertilizante Orgânic, Zea mays,. Abstract The objective of the work was to evaluate the influence of the biostimulant Fert Bokashi Premium® and microfilter on the nutritional efficiency and productivity of the maize cultivar DKB 290 Pro3, under field conditions. The experimental design was a randomized block with eleven treatments and four replications. The results indicated nutritional gains that influence grain yield, at different application times, planting and leaf. Thus, it was clear the influence of the product Fert Bokashi® activated at seeding planting, with higher averages when applications occurred at seeding and in vegetative stages V4 and V8. For the microfilter, it was observed that the nutrients Fe, Cu, K and S, maintained the levels required for the culture, indicating that to increase productivity it is necessary to supply nutrients that guarantee the plants their needs, and that productivity has a close relationship with the rates of nutrients extracted by the plants. The use of activated biofertilizer Fert Bokashi® increases the levels of Fe, K and S, which interfere in the maize productivity under field conditions, and when applied in planting and in stages V4 and V8. Keywords: Fert Bokashi. Organic Fertilizer. Zea mays.

Landrace Maize Varieties Used as Phytoremediation of Contaminated Soil with 2,4-D + Picloram

The use of herbicides such as 2,4-D + picloram in livestock areas can contaminate and hinder the use of the production system for subsequent crops of other crops. The objective of the research was to evaluate the ability of landrace maize varieties to reduce contamination of soil treated with 2,4-D + picloram, simulating existing conditions in the Amazon Biome. The experiment consisted of 6 phytoremediation treatments (4 landrace maize varieties, 1 hybrid maize cultivar and 1 control without cultivation), 2 herbicide conditions (with and without) and 3 evaluation periods (28, 56 and 84 days). The soil was contaminated and the maize was subsequently cultivated under the herbicide conditions mentioned above. After each evaluation period, soil samples were collected, which were used to mount bioassays by growing cucumber (plants sensitive to the herbicide). Emergence, aerial dry mass and root dry mass were evaluated. All variables were affected by the herbicide residue. However, the reduction in herbicide persistence in each evaluation period was notable, resulting in the normal reestablishment of bioindicator seedlings, especially in the last evaluation at 84 days. The samples obtained in the soil cultivated with the varieties CR purple and CR white showed the best conditions for the development of cucumber, demonstrating the potential to be studied in phytoremediation programs.

Productivity and composition of maize biomass in the central agroclimatic region of the Komi Republic

In the Komi Republic agricultural production and crops are characterized by low heat availability, short growing season, poor and acidic soil. This determines the selection of cultivated plants. In order to develop and increase the efficiency of northern crop production, expanding the range of cultivated crops through new varieties and hybrids adapted to cold climates is a priority. Over the past twenty years in the central agroclimatic region of the Komi Republic the period with temperatures above 10 °C has increased from 88 to 95 days, and the sum of active temperatures has increased from 1400 to 1560 °C. This allows to expand the range of cultivated fodder crops, including new varieties of corn. Studies on the possibility of growing of maize cultivars (Zea mays L.) in the central agro-climatic region of the Komi Republic were carried out. The subject of this study was the modern maize cultivar, Dork, an early three-line hybrid characterized by rapid growth, cold and drought resistance in the initial stages of development. Zea mays plants were grown in a field on an area of 100 m2 near Syktyvkar (61.67 N, 50.76 E). Seeds of Zea mays were sown late, June 20, due to cold and raw weather in May – first decade of June. At a sum of effective temperatures of less than 1800 °C the Dorka cultivar formed 564 c/ha of green (fresh) mass and 106 c/ha of dry mass. In dry biomass the content of soluble sugars consist of 200 g/kg, carotenoids was 140 g/kg, amino acids – 52 g/kg, among them essential amino acids – 18.7 g/kg. The biomass of maize cultivar, Dorka, is rich in calcium and magnesium. Thus, in terms of crop productivity and nutritional value of biomass, the maize cultivar, Dorka, is promising for cultivation in the central and southern agro-climatic regions of the Komi Republic. It is suitable for use as green feed and silting.

Exploring options for improving maize productivity for small farmers in the Loess Plateau

<p>Millions of small farmers rely on maize (Zea mays L.) produced in the Loess Plateau of China. However, little has been reported on the effects of plastic mulch and maize cultivar on crop yield in the check dam environment. The objectives of this experiment were to determine the effects of maize cultivar and plastic mulch on photosynthetic characteristics and grain yield when grown in the check dam environment. Three maize cultivars were assessed with and without plastic mulch in 2016 and 2017 in Ansai County, Shaanxi Province, China. Results showed that mulch increased grain yield by 10.5% in 2016 and 11.3% in 2017 across all cultivars. Among all cultivars, ‘Xianyu335’ had the highest grain yield under both mulch and no mulch. Grain yield was significantly correlated with soil water content in the 0-20 cm layer. Soil temperature under mulch decreased with increasing soil depth. Averaged over soil depths, mulch increased soil temperature from 0.2 to 1.9 °C over the entire growing season. Maize cultivar directly determined photosynthetic characteristics. Grain yield was more closely related to photosynthetic rate in July than in August, and was significantly associated with stomatal conductance and transpiration rate. Our findings suggest that photosynthetic characteristics is an important index affecting maize grain yield for small farmers using check dams in the Loess Plateau.</p>