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Jabones y detergentes como plaguicidas

Tema en 'Plagas y enfermedades' comenzado por AJPA, 15/2/18.

  1. AJPA

    AJPA NPISA: la proxima vez espero equivocarme menos

    Más de 4000 mensajes
    Ingreso:
    8/10/15
    Mensajes:
    6.749
    "Gracias":
    7.248
    Puntos trofeo:
    2.291
    Ubicación:
    fincas a 100-300 msnm, zona calcarea, Oriente de Asturias, España, Zona climatica C1/Cfb (Köppen-Geiger). zona rusticidad: 9
    Buenas,
    Buscando una informacion sobre el jabon potasico para una consulta en otro subforo he encontrado una referencia que querria compartir aquí también sobre empleo como jabones y detergentes como plaguicidas
    La referencia es:
    https://www.intechopen.com/books/in...nts-and-soaps-as-tools-for-ipm-in-agricultureAgricultural and Biological Sciences » "Integrated Pest Management (IPM): Environmentally Sound Pest Management", book edited by Harsimran Kaur Gill and Gaurav Goyal, ISBN 978-953-51-2613-3, Print ISBN 978-953-51-2612-6, Published: August 31, 2016 under CC BY 3.0 license. © The Author(s).
    Tomislav Curkovic S. (2016). Detergents and Soaps as Tools for IPM in Agriculture, Integrated Pest Management (IPM): Environmentally Sound Pest Management, Dr. Harsimran Gill (Ed.), InTech, DOI: 10.5772/64343. Available from: https://www.intechopen.com/books/in...nts-and-soaps-as-tools-for-ipm-in-agriculture
    Creo que puede ser de interés especialmente para aquellos colegas que tienen arboles/arbustos/frutos del bosque de poco porte y que no les agrada mucho el empleo de fitosanitarios de síntesis. He pensado, entre otros, en @Francisco Figueroa que hace unos dias no lo leo en el foro y espero que todo este bien con y para él. Yo, y creo que no soy el único, lo echo de menos.
    Dado que el documento es open source entiendo que no hay problemas para incluir un apartado aquí y mas abajo pongo el de los mecanismos de actuación que creo servirá para que podamos darnos cuenta como los jabones y detergentes pueden actuar sobre las plagas.
    ----------------
    Este articulo tambien se puede consultar/descargar en researchgate
    https://www.researchgate.net/public...nts_and_Soaps_as_Tools_for_IPM_in_Agriculture
    1.2. Modes of action of detergents and soaps as pesticides
    The modes of action for D + S against pests have not been well understood yet [30, 31]. In fact, D + S are not considered on the IRAC (Insecticide Resistance Action Committee) lists that classify the pesticides mode of action for those with known specific target sites [32]. This is because D + S are not known to act at specific target sites, but at multiple sites [11]. Despite that, wax removal, arthropod dislodging, and drowning have been mentioned as lethal mechanism in D + S.
    1.2.1. Wax removal
    The arthropod epicuticle is mainly made of lipids. The outermost part is a wax layer constituted mostly by hydrocarbons, serving mainly for waterproofing to avoid dehydration [33]. This is a serious threat for small insects and mites, particularly those sessile and exposed individuals. It has been proposed that when arthropods are sprayed with detergent, lipids are removed from the epicuticle, losing its waterproof ability, which in turn causes important water losses and, finally, the death of treated pests [34]. In fact, a significant reduction in both residual epicuticular lipids and body weight (assumed to occur mainly due to water losses) on the obscure mealybug Pseudococcus viburni Signoret (Hemiptera: Pseudococcidae) sprayed with detergent solutions was measured ([35], Table 1). After the spray, water losses reached up to 3% of body weight 7 h after exposure, and residual waxes were 88–73% below when compared with the control (check) at 24 h. Mortality was positively related with both water losses and wax removal when the agriculture detergent TS 20135 was used, but no significant relationship was found when the surfactants alone (excluding the co-adjuvants from the formulation) were tested.
    Santibáñez [35] proposed that mealybug mortality by exposure to detergents might be caused by several mechanisms, including the initial wax removal that might lead to further damage of the integument, but this was not demonstrated. Many reports of pest management with D + S reveal that individuals present a degreased and dehydrated aspect after exposure, suggesting that water losses might be involved in mortality. For instance, the cotton aphid Aphis gossypii Glover (Hemiptera: Aphididae) nymphs and adults were strongly dehydrated and their bodies collapsed when evaluated 48 h after the spray with an agricultural detergent [9]. Wax removal (assumed to lead to dehydration) is also evident after exposure to detergents, causing dramatic changes in mealybugs, even a few minutes after the spray ([8, 11], Figure 1 shows effects on hemipterans either sprayed or immersed in solutions).
    Treatments1
    Detergent (mL a.i.2/100 mL)
    Water loss3 (mg)
    Residual waxes4 (mg/mL)

    LC90
    8.17
    1.85 a5
    14.95 b5
    LC50
    4.45
    1.48 b
    6.85 b
    LC10
    0.74
    0.89 c
    54.76 a
    Control
    0.00
    0.47 c
    55.06 a
    Table 1.
    Pseudococcus viburni water losses and residual waxes after detergent sprays.
    1 LC = lethal concentration estimated by Probit analysis; study conducted using a Potter tower, control sprayed with water.
    2 Active ingredient, the sum of surfactants formulated in TS 2035 (see Table 3)
    3 Difference between initial (before) and final weight.
    4 Residual waxes extracted with chloroform from 20 P. viburni adult females after detergent spray.
    5 Means with different letters in a column are significantly different (p ≤ 0.05) according to Tukey’s test. Data extracted from Santibáñez [35].
    Figure 1.
    Healthy hemipterans before (left column) and either minutes or a few hours after exposure in 1–2% detergent solutions (right), presenting symptoms of dehydration, browning, body collapse, and wax removal. A, Pseudococcus longispinus Targioni and Tozzetti (Pseudococcidae); B, P. longispinus after 5-s immersion in SU 120 (see details in Table 3); C, Aphis gossypii Glover (Aphididae); D, effect of TS 2035 on A. gossypii; E, Eriosoma lanigerum (Hausmann) (Eriosomatidae); F, effect of TS 2035 on E. lanigerum; G, Siphoninus phillyreae (Haliday) (Aleyrodidae); H, S. phillyreae a few days after sprayed.
    Detergents1 (%, v/v)
    % dislodgment2 (D)
    % mortality (M)
    CD = 100×D/[D + M])

    1.00%
    22.2
    59.4
    27.2
    0.50%
    21.7
    32.6
    40.0
    0.25%
    14.1
    17.6%
    44.5
    Control3
    3.2
    18.8%
    14.5
    Table 2.
    Panonychus citri dislodgement (D), mortality (M) at 24 h, and contribution of dislodgement (CD) to the control (D + M), after immersion of infested lemon leaves in the laboratory.
    1 Quix solutions (see Table 3).
    2 Individuals found after immersion for 5 s + filtration.
    3 Tap water. Data extracted from Curkovic and Araya [37].
    1.2.2. Arthropod dislodgement
    Detergents and soaps contain surfactants, that is, compounds that reduce the surface tension of solutions, enhancing their capability to wet and wash arthropods off. Thus, sprays can dislodge motile forms of phytophagous pests, as nymphs and adults of mites, thrips, etc. (particularly when the solution runoffs on the leaves). Even not necessarily all removed individuals die, and dislodgement causes significant reductions of populations infesting the foliage. Dislodgement has been highlighted as an anti-herbivore trait [36] that reduces their phytophagous performance on the plant. In a laboratory study, up to 22% dislodgment of the citrus red mite Panonychus citri McGregor (Acari:Tetranychidae) infesting lemon (Citrus × limon (L.) Burm.f.) leaves occurred after immersion in a detergent solution at 1% (v/v), significantly greater than water alone [37]. Mite mortality was also greater along with detergent concentration, but the relative contribution of dislodgment to total control (dislodgment + mortality) was even greater (44.5%) when the lower concentration (0.25%, v/v) was used (Table 2). In another study, 22% of the Chilean false red mite Brevipalpus chilensis Baker (Acari: Tenuipalpidae) were washed off vine leaves after immersion in a detergent (see Table 3 for details) solution, but lower concentrations contributed less to total control [38], suggesting that dislodgement depends on the type of detergent and/or the mite species.
    Not many reports have demonstrated dislodgment when soaps and detergents are used for pest control, although surfactants have been mentioned as useful tools to wash out arthropods plant substrates (including plant organs) for cleaning produce or pest sampling purposes [39]. For instance, ca. 28% of the western flower thrips, Frankliniella occidentalis (Pergande), were removed after the immersion in a 0.1% surfactant solution (see Table 3) from infested Coleus shoots (Lamiaceae), but the thrips were apparently not harmed [40].
    1.2.3. Drowning
    Arthropod respiratory system is formed by a net of conducts (traqueae) that allow direct gas exchange with tissues. It is connected to the exterior by spiracles that regulate opening by muscles [33]. The surfactant properties of detergents and soaps allow the solutions to enter the spiracles [41, 42]. The solutions fill the traqueae, causing drowning and death. No reports have been found describing this mechanism for pest control, but several papers have mentioned drowning as a mortality factor after surfactant sprays on insects and mites [43, 44]. In larger insects, this seems to be a lethal mechanism after exposure to D + S [43].
    1.2.4. Other mechanisms
    Interference with cellular metabolism [41], repellency [30], breakdown of cell membranes [42], abnormal juvenile development [12], caustic activity, uncoupling oxidative phosphorylation, and/or even nervous system disruption [45] have been also indicated as possible modes of action of D + S, but further details have not been found. Interestingly, in nature, surfactants have been highlighted as a mechanism of defense developed by some insects against their predators by producing oral secretions containing surfactants that, for instance, stop ants attacking beet armyworm, Spodoptera exigua (Hübner) caterpillars (Lepidoptera: Noctuidae). After exposure, the ants covered by the secretion are engaged in intensive grooming that persisted for a few minutes, enough to save the caterpillar. Besides, after cleaning, ants were reluctant to attack a second time [46]. In fact, the author has regularly poured pure dishwashing detergents (~5 mL on their path) to successfully stop ant columns at home.
    Suerte y saludos cordiales
    AJPA
    Francisco Figueroa y Torpe dan las Gracias.

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