25 research outputs found
Comparison between pine bark and coconut husk sorption capacity of metals and nitrate when mixed with sewage sludge
Waste products such as biosolids and wood wastes have been frequently used in container production of plants. The use of biosolids in agriculture is a beneficial mean of recycling the by-products of waste-water treatment. However, care must be taken to avoid environmental or human health problems via run-off and leaching. The objective of this work is to compare the retention capacity of cadmium, lead, zinc and nitrate between pine bark (PB) and coconut fibre (F) when mixed with increasing amounts of composted sewage sludge (CSS) (0%, 15% and 30% (v/v)). Substrates were packed into leaching columns and irrigated with deionised water every 2 days. Leachates were collected during 1 month, and nitrate, Zn, Cd, Pb, EC and pH were monitored along the experiment. PB columns leached lower amount of nitrate than the coconut fibre ones. The same trend was observed for Zn, Cd and Pb. It could be said, that in order to minimize the environmental risks of using sewage sludges our results indicate that it is preferred to mix the sludge with pine bark instead than with coconut husk
Impact of the application of monosilicic acid to grapevine (Vitis vinifera L.) on the chemical composition of young red Mencia wines
Impact of applying monosilicic acid to grapevines during ripening on chemical composition of Mencía red wines in an area where fungal diseases during summer are common was examined. The foliar application of monosilicic acid to grapevines led to a less oxidized wine, with lower levels of acetic acid, acetaldehyde, ethyl acetate and diacethyl; this should be considered as positive from a sensory point of view. Wines made with silicon-treated grapes also contained lower levels of gluconic acid and glycerol, which are chemical markers of wines made with botrytized grapes, as well as higher contents of total phenols, anthocyanins and tannins. Furthermore, the contents of several mid-chain alcohols were higher (p < 0.05) in wines made with grapes from silicon-treated plantsThe authors gratefully acknowledge the financial support by the FEDER/Spanish Ministry of Science, Innovation, and Universities Project: RTI2018-096268-B-I00. This work was partially supported by Comunidad de Madrid (Spain) and Structural Funds 2014–2020 (ERDF and ESF) (Project AGRISOST-CM S2018/BAA-4330
Root silicon addition induces fe deficiency in cucumber plants, but facilitates their recovery after fe resupply. A comparison with si foliar sprays
Silicon has not been cataloged as an essential element for higher plants. However,
it has shown beneficial effects on many crops, especially under abiotic and biotic
stresses. Silicon fertilization was evaluated for the first time on plants exposed to
fluctuations in an Fe regime (Fe sufficiency followed by Fe deficiency and, in turn, by
Fe resupply). Root and foliar Si applications were compared using cucumber plants that
were hydroponically grown in a growth chamber under different Fe nutritional statuses
and Si applied either to the roots or to the shoots. The SPAD index, Fe, and Mn
concentration, ROS, total phenolic compounds, MDA concentration, phytohormone
balance, and cell cycle were determined. The results obtained showed that the addition
of Si to the roots induced an Fe shortage in plants grown under optimal or deficient
Fe nutritional conditions, but this was not observed when Si was applied to the leaves.
Plant recovery following Fe resupply was more effective in the Si-treated plants than in
the untreated plants. A relationship between the ROS concentration, hormonal balance,
and cell cycle under different Fe regimes and in the presence or absence of Si was
also studied. The contribution of Si to this signaling pathway appears to be related
more to the induction of Fe deficiency, than to any direct biochemical or metabolic
processes. However, these roles could not be completely ruled out because several
hormone differences could only be explained by the addition of Si
Root silicon addition induces fe deficiency in cucumber plants, but facilitates their recovery after fe resupply. A comparison with si foliar sprays
Silicon has not been cataloged as an essential element for higher plants. However,
it has shown beneficial effects on many crops, especially under abiotic and biotic
stresses. Silicon fertilization was evaluated for the first time on plants exposed to
fluctuations in an Fe regime (Fe sufficiency followed by Fe deficiency and, in turn, by
Fe resupply). Root and foliar Si applications were compared using cucumber plants that
were hydroponically grown in a growth chamber under different Fe nutritional statuses
and Si applied either to the roots or to the shoots. The SPAD index, Fe, and Mn
concentration, ROS, total phenolic compounds, MDA concentration, phytohormone
balance, and cell cycle were determined. The results obtained showed that the addition
of Si to the roots induced an Fe shortage in plants grown under optimal or deficient
Fe nutritional conditions, but this was not observed when Si was applied to the leaves.
Plant recovery following Fe resupply was more effective in the Si-treated plants than in
the untreated plants. A relationship between the ROS concentration, hormonal balance,
and cell cycle under different Fe regimes and in the presence or absence of Si was
also studied. The contribution of Si to this signaling pathway appears to be related
more to the induction of Fe deficiency, than to any direct biochemical or metabolic
processes. However, these roles could not be completely ruled out because several
hormone differences could only be explained by the addition of Si