Effectiveness of Azadirachtin (NeemAzal-T/S) in Controlling Pear Psylla (Cacopsylla pyri) and European Red Mite (Panonychus ulmi)
Efektivnost azadirahtina (NeemAzal-T/S) u suzbijanju kruškine buve (Cacopsylla pyri) i crvene voćne grinje (Panonychus ulmi)
Pregled/ Otvaranje
Autor
Marcic, Dejan
Ogurlic, Irena
Prijovic, Mirjana
Peric, Pantelija
Ključne reči
AzadirachtinCacopsylla pyri
Panonychus ulmi
Control
suzbijanje
Metadata
Prikaz svih podataka o dokumentuApstrakt
Here we present the results of field trials conducted in Serbia to evaluate the effectiveness
of a neem-based product, NeemAzal-T/S (containing azadirachtin-A as its active ingredient
in the form of an emulsifiable concentrate) against pear psylla (Cacopsylla pyri) and
European red mite (Panonychus ulmi).
Efficacy evaluation against C. pyri was carried out in a commercial pear orchard of the
Williams pear cultivar, located at Borkovac (Ruma). The insecticides were applied at BBCH
09 pear growth stage, several days before the beginning of hatching of the first generation
larvae. The efficacy of azadirachtin was compared to that of mineral oil, abamectin
and diflubenzuron. Efficacy evaluation 18 DAT showed total termination of egg laying
by C. pyri after treatments with azadirachtin and abamectin, while some new (white) eggs
were found after treatment with mineral oil. Diflubenzuron treatment failed to fully stop
egg laying, but the number of white eggs was significantly lower than it was in the control.
Azadirachtin and abamectin achieved 100% efficacy, while the effectiveness of mineral oil
was 97.4%, and that of diflubenzuron a mere 59%. All four insecticides significantly reduced
the number of older (yellow) eggs and larvae, the efficacy being 80.5-92.6% (yellow eggs),
69.8-79.3% (larvae I-III instar) and 94.3-100% (larvae IV-V instar). In evaluation 38 DAT, azadirachtin,
abamectin and mineral oil achieved 100% efficacy against white and yellow eggs,
while diflubenzuron achieved 93% and 86.9% efficacy. All four insecticides were found to
demonstrate high efficacy against I-III instar larvae (99.2-100%), but mineral oil treatment
alone achieved high efficacy against IV-V instar larvae (92.4%) as well.
Efficacy evaluation against P. ulmi was carried out in a commercial orchard of the Red
Chief apple cultivar located at Morović (Šid). Azadirachtin efficacy in controlling a summer
population of European red mite was compared to a mineral oil, clofentezine and spirodiclofen.
The acaricides were applied when the number of P. ulmi motile forms was below
the orientational damage threshold of 3 motile forms per leaf. Azadirachtin reduced significantly
the number of motile forms, leaving it well below damage threshold by the end
of the trial. Good control efficacy was achieved (77.2-90.4%), the highest level of efficacy being recorded at the end of the trial 38 DAT. In mineral oil treatment 7 DAT, efficacy was
92.4%; 14 DAT and 21 DAT it was 75.2% and 78.9%, and it dropped to below 60% at the end
of the trial. The efficacy of clofentezine (39.4-68.2%) was unsatisfactory, which is probably
the result of a resistance developing under high selection pressure of these compounds in
the Morović locality in preceding years, while the newly introduced acaricide spirodiclofen
showed high and long-lasting efficacy (97.2%, 38 DAT).
The results of the trials are discussed in terms of improving management of the populations
of European red mite and pear psylla. Prikazani su rezultati poljskih ogleda realizovanih u Srbiji u cilju ocene efektivnosti nimderivata
NeemAzal-T/S (koji sadrži azadirahtin-A kao aktivnu materiju u formi koncentrata
za emulziju) u suzbijanju kruškine buve (Cacopsylla pyri) i crvene voćne grinje (Panonychus
ulmi).
Ogled ocene efektivnosti suzbijanja C. pyri izveden je u komercijalnom zasadu kruške
sorte Viljamovka u Borkovcu (Ruma). Insekticidi su primenjeni u fenofazi BBCH 09, nekoliko
dana pre početka piljenja larvi prve generacije. Efikasnost azadirahtina upoređena je sa efikasnošću
mineralnog ulja, abamektina i duflubenzurona. Ocena efekata 18 DPT pokazala je
da je polaganje jaja C. pyri potpuno zaustavljeno u tretmanima azadirahtinom i abamectinom,
dok je u tretmanu mineralnim uljem ipak registrovan izvestan broj novih (belih) jaja.
U tretmanu diflubenzuronom polaganje jaja nije zaustavljeno, ali je broj belih jaja bio značajno
niži u poređenju sa kontrolom. Efikasnost azadirahtina i abamektina iznosila je 100%
a efikasnost mineralnog ulja 97,4%, dok je efikasnost diflubenzurona bila svega 59%. Sva četiri
insekticida značajno su redukovala broj starijih, žutih jaja i larvi, a efikasnost je iznosila
80,5-92,6% (žuta jaja), 69,8-79,3% (larve I-III stupnja) i 94,3-100% (larve IV-V stupnja). U oceni
38 DPT u tretmanima azadirahtinom, abamektinom i mineralnim uljem zabeležena je 100%
efikasnost redukcije broja belih i žutih jaja, dok je diflubenzuron ostvario efikasnost od 93%
i 86,9%. Sva četiri insekticida ispoljila su visoku efikasnost u suzbijanju larvi I-III stupnja (99,2-
100%), ali je samo u tretmanu mineralnim uljem zabeležena visoka efikasnost i protiv larvi
IV-V instar stupnja (92,4%).
Ogled ocene efektivnosti suzbijanja P. ulmi izveden je u komercijalnom zasadu jabuke
sorte Red Chief u Moroviću (Šid). Efikasnost azadirahtina u suzbijanju letnje populacije crvene
voćne grinje upoređena je sa efikasnošću mineralnog ulja, klofentezina i spirodiklofena.
Akaricidi su primenjeni u vreme kad je brojnost P. ulmi bila ispod orijentacionog praga
štetnosti od 3 pokretne forme po listu. Azadirahtin je značajno redukovao broj pokretnih
formi, koji je do kraja ogleda ostao znatno ispod praga štetnosti. Postignuta je dobra efikasnost
suzbijanja (77,2-90,4%), s tim da je najviši nivo efikasnosti registrovan na kraju ogleda,
38 DPT. U tretmanu mineralnim uljem, 7 DPT ostvarena je efikasnost 92,4%; 14 DPT and 21
DPT efikasnost je bila 75,2% i 78,9%, da bi na kraju ogleda pala ispod 60%. Efikasnost klofentezina
(39,4-68,2%) bila je nezadovoljavajuća, što je verovanto rezultat rezistentnosti nastale
pod snažnim selekcionim pritiskom ovim akaricidom prethodnih godina, dok je efikasnost
novog akaricida spirodiklofena bila visoka i dugotrajna (97,2%, 38 DPT).
Ostvareni rezultati razmatrani su u kontekstu unapređenja suzbijanja populacija ove
dve štetne vrste.