5 research outputs found
Effects of foliar fertilization of a biostimulant obtained from chicken feathers on maize yield
Due to the important contribution that it makes to human nutrition, maize is one of the most widely-consumed cereals in the world. There is, therefore, high demand for fertilizers that will maintain maize production at both high yield and quality levels. The objective of this work was to study the effect of foliar fertilization using a biostimulant, obtained by enzymatic hydrolysis from chicken feathers, on the productivity and quality of maize crops (Zea mays, L. cv PR32W86 Pioneer), located in Trujillanos (Extremadura, Spain), over two consecutive seasons. Foliar biostimulant/biofertilizer was applied three times each season and at two rates (3.6 and 7.2 l ha−1). At the higher rate and for both seasons, foliar fertilization significantly increased the leaf concentrations of macro- and micronutrients, while grain protein content and yield increased by 26% and 14%. These results suggest that the foliar use of this biostimulant could be of great interest to the farmer for improving both maize crop yield and quality.Ministerio de Economia y Competitividad CTM2015-64354-C3-1-RMinisterio de Economia y Competitividad CTM2015-64354-C3-3-RJunta de Andalucía RNM-2011-788
An approach to zoning in the wine growing regions of “Jerez-Xérès-Sherry” and “Manzanilla-Sanlúcar de Barrameda” (Cádiz, Spain)
The Appellations of Origin “Jerez-Xérès-Sherry” and “Manzanilla-Sanlúcar de Barrameda” occupy one of the oldest
and most world renowned viticultural areas in the peninsula, but it is not exempt from the serious problems that are
to be found throughout the sector. In order to try to adapt to the present situation, zoning plans are being promoted
whereby priority is given to the quality of the product, sustainable development and the economic interests. This work
undertakes an approach to the viticultural zoning. The nutritional state of the grapevines is studied by means of foliage
analysis at veraison. The quality of production was measured by means of the berry weight and the analysis of the
most usual variables of the must at the time of harvest (°Baumé, pH and titratable acidity) over five seasons, in the 21
plots where the soil profiles were opened for analysis. As a result of applying statistical analysis, the plots are grouped
into five classes, two of which are subdivided. The most significant differences were established between the plots of
class CL1, on Miocene limestone, and those of class CL5, on Pliocene-Quaternary sands and clays. Class CL1 presented
the highest content of ash (mean ± sd CL1; CL5) (15.36 ± 1.73; 12.36 ± 1.77) and calcium (3.42 ± 0.90; 2.65 ± 0.72),
the lowest berry weight (2.10 ± 0.30; 2.47 ± 0.50) and a greater Baumé degree (10.55 ± 0.86; 9.63 ± 0.98) than the CL5.
This new approach takes other essential factors for the quality of the production into account such as the climate and
the geomorphology (altitude, slope, and physiography)Las Denominaciones de Origen Jerez-Xérès-Sherry y Manzanilla-Sanlúcar de Barrameda ocupan una de las zonas
de producción más antiguas de la península y de mayor reconocimiento a nivel mundial, aunque no están exentas de la
grave problemática por la que atraviesa el sector. Para intentar adaptarse a la situación actual se están promoviendo planes
de zonificación en donde prima la calidad del producto, el desarrollo sostenible y los intereses económicos. En este
trabajo se realiza una aproximación a la zonificación vitícola. Para ello, se estudia el estado nutricional de las vides
mediante el análisis foliar en el envero, la calidad de producción mediante el peso de los granos de uva y el análisis de
las variables más usuales del mosto en la época de vendimia (°Baumé, pH y acidez total) durante 5 campañas, en 21
parcelas coincidentes con la apertura de los perfiles. Como resultado de aplicar el análisis estadístico, se han agrupado
las parcelas en cinco clases, dos de ellas a su vez subdivididas. Las principales diferencias significativas se encontraron
en las parcelas de las clases CL1, sobre albarizas del Mioceno, y las de la clase CL5, sobre arenas y arcillas del
Plioceno-Cuaternario. La clase CL1 presenta el contenido más elevado de cenizas (mean ± sd CL1; CL5) (15,36 ± 1,73;
12,36 ± 1,77) y calcio (3,42 ± 0,90; 2,65 ± 0,72), el menor peso de grano de uva (2,10 ± 0,30; 2,47 ± 0,50) y un mayor
grado Baumé (10,55 ± 0,86; 9,63 ± 0,98) que la CL5. Esta nueva aproximación tiene en cuenta otros factores esenciales
para la calidad de la producción como son el clima y la geomorfología (altitud, pendiente, fisiografía
Use of a biostimulant obtained from okara in the bioremediation of a soil polluted by used motor car oil
In this manuscript we studied in the laboratory the bioremediation effects of a biostimulant obtained from okara by enzymatic hydrolysis processes in a soil polluted with used motor-car oil at a rate of 1 % (w/w) over an 89-day period. The biostimulant was added to the soil 6 times during the incubation period at a rate of 2 %. Dehydrogenase activity and the evolution of polycyclic aromatic hydrocarbons (PAHs) and pseudo total heavy metals in soil were studied. The successive applications of the biostimulant to the polluted soil gradually increased PAHs degradation during the experimental period. Thus, at the end of the experiment, the application of the biostimulant decreased the concentration of naphthalene in soil by 74 %, while PAHs with 3, 4, 5 and 6 aromatic rings had been reduced by around 58 %, 44 %, 30 % and 23 %, respectively. This degradation is possibly due to the high number of low molecular weight peptides (<300 Da) in the biostimulant which are readily available for PAHs-tolerant soil microorganisms that accelerate the degradation of the said toxins. The concentration of heavy metals in the oil used was not very high and consequently the dehydrogenase activity was not negatively affected
Response of Biochemical Properties in Agricultural Soils Polluted with 4-Chloro-2-methylphenoxyacetic Acid (MCPA) under Severe Drought Conditions
The soil moisture content can vary the behavior of biochemical activity and its incidence on herbicides. The objective of this manuscript was to assess, under controlled laboratory conditions, whether a prolonged 75-day drought can affect the behavior of 4-chloro-2-methylphenoxyacetic acid (MCPA) herbicide and biochemical properties in three agricultural soils (Typic Xerofluvent, SA, Typic Haploxeralf, SB, and Vertic Chromoxert, SC). During the 75 experimental days, two irrigation levels were maintained: (1) watered soils during this experimental period, and (2) non-watered soils, where no water was supplied during the experimental period. The evolution of the herbicide and the biochemical properties were different depending on the soil moisture status. In the SA, the biochemical properties decreased until day 35 after initiating the experiment, whereas in the SB and SC, the biochemical parameters decreased until days 25 and 45, respectively. The application of herbicide to the non-watered soil increased the inhibition of biochemical properties. In non-watered SA, MCPA degradation occurred at day 45 after initiating the experiment, whereas in SB and SC, MCPA degradation occurred at days 35 and 60 after starting the incubation process, respectively. These results suggest that the soil persistence of MCPA under drought conditions increases, and consequently increases soil contamination.Ministerio de Ciencia e Innovación PID2021-124964OB-C2
Use of Biostimulants Obtained from Sewage Sludge for the Restoration of Soils Polluted by Diuron: Effect on Soil Biochemical Properties
The use of biostimulants in the bioremediation of polluted soils in order to eliminate/reduce the toxic effects of pesticides on the soil is currently a very common environmental practice. In this study, we studied the bioremediation effect of three biostimulants obtained from sewage sludge by way of an enzymatic hydrolysis and fermentation process in a diuron-contaminated soil for 55 days under laboratory conditions. During this period of time, the enzymatic activities, bacterial community and the evolution of diuron in the soil were analyzed. Compared with the unpolluted soil, the application of diuron decreased the dehydrogenase, β-glucosidase and phosphatase activities by 60%, 40.7%, and 60.6%, respectively. The Gram-positive bacterial population was decreased by 48.5%, while the Gram-negative population was decreased by 57.7% and the fungal population was decreased by 54.3%. The application of the three biostimulants to the soil decreased the diuron concentration. However, this decrease was higher when the biostimulant obtained by enzymatic hydrolysis was applied. This may be due to the fact that this biostimulant contains a higher quality of low molecular weight proteins than the other two biostimulants obtained by fermentation processes.Ministerio de Ciencia e Innovación PID2021-124964OB-C2