1,720,984 research outputs found
Effect of cannon sprayer configuration and adjustment on spray deposit and ground drift in high-tunnel strawberry cultivation
No full textEfficient spraying is essential for modern agricultural production to ensure biological efficacy and high-quality and abundant harvests. At the same time, it is crucial to minimise the negative impact of plant protection products on the environment. Hence, it is necessary to implement the appropriate technical and technological factors for the treatment and consider the conditions under which the spray application is carried out (Cieniawska et al., 2024). The aim of this study was to evaluate the use of alternative application techniques, i.e., the reduction in application volume, the use of an electrostatic charger and air injection nozzles, in comparison to a standard cannon sprayer application in high-tunnel cultivation in Trentino (Northern Italy). To do this, paper collectors were placed along strawberry rows at different distances from the front openings of the tunnels, and the tunnels were sprayed with a tracer dye (tartrazine) using the mentioned application techniques to evaluate spray deposition. Moreover, some Petri dishes were placed at different distances outside the tunnel to estimate the ground deposit due to spray drift. Deposits were similar for all the application techniques for the external part of the canopy. Inside the canopy, slight significant differences were found only for the deposits retrieved in the central part of the tunnel (Kruskal–Wallis test, p0.05). In this case, the electrostatic charged spray showed the highest average value of deposit, and the air injection nozzles marked the lowest. However, the ground deposit retrieved outside the tunnel for the electrostatic configuration was not different from most of the other equipment arrangements. The sprayer equipped with air injection nozzles showed significantly higher losses close to the tunnel and significantly lower losses starting from 3.5 m from the tunnel opening in comparison to the other sprayer configurations. In general, these spray techniques, singularly or combined with one another, could be considered as alternatives to the reference spray practise in strawberries, and when put together, they may ensure better efficiency of applications and a reduction in negative environmental impacts
L’antonomo danneggia ora anche i frutti della fragola
No full textOltre ai fiori e alle foglie, ora Anthonomus rubi
provoca rosure ai frutti, con perdite di produzione
fino anche al 60%. L’impiego di un attrattivo sessuale con trappole cromotropiche gialle o verdi
sembra utile per un corretto monitoraggio dell’insetto. Gli insetticidi testati sono risultati poco efficaci. La difesa deve puntare
sicuramente su un approccio integrato
Investigations on spray drift mitigation by means of artificial barriers in high tunnel strawberries
Full text linkThis paper summarises the results of some trials carried out to verify the capability of artificial barriers to mitigate spray drift when treating soft fruits, particularly strawberry, cultivated under high plastic tunnel and treated by cannon sprayers. The possibility to protect plants and their production from atmospheric agents is one of the main reasons for the wide adoption of plastic tunnel in soft fruit cultivations. The protective structure can often integrate a series of tools like anti-insect nets or plastic sheet closures that can help to mitigate drift during spray applications by filtering the airflow mixed with small droplets and catching those prone to drift. Preliminary trials showed the capability of the net to reduce the amount of liquid deposited behind it. Spray application trials in high tunnels showed that drift mitigation is possible when using different types of barriers, but a lower effect can be expected for the anti-insect net and up to almost complete drift reduction with a plastic film. The results of spray deposition in the strawberry canopy could not show a clear effect of interference between the artificial barrier and the mix of airflow and droplet
Substrati organici per fragola fuori suolo da prodotti derivati: primi test su materiali disponibili in Trentino
No full textLa fragola coltivata fuori suolo abbisogna di un substrato con definite caratteristiche fisico-chimiche, porosità e capacità di scambio in particolare, che determinano condizioni igroscopiche e nutrizionali idonee allo sviluppo delle piante. La torba bionda di sfagno, a debita granulometria, ha evidenziato tali condizioni, divenendo, anche per economicità e facilità d’uso, il materiale privilegiato per questa coltivazione. Negli ultimi anni, spinte ambientalistiche alla riduzione dell’utilizzo di risorse naturali lentamente rinnovabili da un lato e problematiche geopolitiche che presumono maggiori costi e rischi per produzione e trasporto del materiale dall’altro, hanno accelerato la ricerca di possibili alternative. Le stesse motivazioni socioeconomiche, contemporaneamente, hanno fatto nascere realtà che mirano a recupero e trasformazione di prodotti, o sottoprodotti, di varia derivazione: domestica, industriale, energetica o agricola. Fra queste, in Trentino, il compostaggio di rifiuti domestici, la biodigestione di reflui zootecnici, la cippatura di residui arborei ad uso termo-energetico, e la cippatura di residui della gestione del verde urbano originano grosse quantità di materiali organici dalle caratteristiche fisico-chimiche più dissimili. L’incrocio di queste due iperboli economico-ecologiche, una interna e una esterna al settore, ha portato a valutarne eventuali impieghi anche nelle coltivazioni fuori suolo. Lo studio mira quindi a sfruttare tali materiali per ridurre l’uso della torba attraverso la sostituzione, totale o parziale, o il suo riutilizzo per più cicli produttivi. Dai test preliminari dei comportamenti fisico-idrici e chimico-nutrizionali dei materiali, si sono determinate e sperimentate formulazioni e metodiche gestionali differenti. Dai primi risultati si può ipotizzare lo sfruttamento di alcuni di essi quali reintegratori della torba già utilizzata in un primo ciclo produttivo. Ad esempio, la sua miscelazione con una quota minoritaria di digestato, abbinata a specifica gestione fertirrigua, ha permesso il suo riutilizzo in un ciclo produttivo biennale con svernamento, limite solitamente invalicabile per il drastico decadimento strutturale della torba riutilizzata
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Investigations on yellowing of chestnut crowns in Trentino (Alps, Northern Italy)
Full text linkYellowing of part or the whole canopy of chestnut trees was observed during
the summer of 2014 in the areas of Tenno, Pranzo and Drena in Trentino,
where chestnut cultivation is traditional on the lateral moraine deposit in a
context of a prevalent limestone lithological substrate. Symptoms were observed on chestnut trees of different ages, either grafted or not, scattered or in stripes along the maximum slope. Investigations were carried out in the
form of field surveys, chemical and molecular analyses of soil and leaves and
greenhouse trials, to assess the damage evolution and its causes. No known
pathogens emerged during the field surveys, and laboratory tests excluded the
presence of phytoplasma infections. A comparison of yellow and asymptomatic
leaves evidenced significant deficiencies of manganese (Mn) and iron (Fe) in
the yellow leaves, though the level of the two nutrients was the same in the
soil below green and yellowed trees. Experimental run-off trials in the greenhouse reproduced the foliage damage with a continuous basic water regime; open-field fertilizations with Mn and Fe led to a slightly recovery on the part
of some treated leaves, thus confirming the hypothesis of a probable, sudden
deficiency of the mentioned microelements. A possible explanation of this
phenomenon could be, on one side, the high precipitation level of 2014, and,
on the other side, the previous outbreaks of the Asian chestnut gall wasp, that
had reduced foliage volume and thus the organic substance in the soil. The
natural recovery from symptoms was clearly visible in trees after four years in
a context of normal rainfall regime and increasing organic acid in the soil, after effective biological control of wasp. Even if related to a particular and rare geological condition, this is the first description of Mn deficiency in Castanea
sativ
- …
