Features of forecasting of leaf-eating insects distribution in the forests of Zhytomyr Polissia

Foliage damage by leaf-eating insects during mass reproduction causes deterioration of the sanitary state of forest and a decrease in its increment. Timely detection of pest foci allows reducing the cost of their elimination and preventing negative consequences for stands. The purpose of this study was to identify the species composition of leaf-eating insects on the territory of State Enterprise Zhytomyrske Forestry and the subcompartments with the greatest threat of foci development of the dominant species – Tortrix viridana, taking into account forest site conditions and stand structure. During the feeding period, the species composition of leaf-eating insects was identified, and after the end of oviposition, the density of Tortrix viridana egg masses was assessed on tree branches selected in subcompartments with different forest site conditions, age, the relative crop density, and proportion of oak in the stand composition. The database of forest inventory (Ukrderzhlisproekt) and the score assessment of the preferences of stands for foci development were used. Eleven species of leaf-eating insects from order Lepidoptera were identified, including 9 species from the family Tortricidae, of which Tortrix viridana dominated. The highest egg mass density of this pest was assessed in fresh dubrava conditions (D2 ), in pure oak plantations aged 40-80 years with a low relative crop density. The average score of stand preference for Tortrix viridana was assessed by forest site conditions (2.93 and 2.88 for seed plantations and coppice forest, respectively), age (3.65), the relative density of stocking (2.6), and oak participation (3.3) in the State Enterprise Zhytomyrske Forestry. The list of subcompartments with a very high and high threat of an outbreak of Tortrix viridana has been established. A survey in these subcompartments would allow timely detection of pest population increase and prevent its development

Insecticidal activity of essential oils of Cupressus arizonica greene and C. sempervirens L. on Tortrix viridana (Lepidotera, Tortricidae)

Tortrix viridana is one of the most important defoliators of oak trees. In 2006 and 2007, this insect caused significant defoliations of oak forests in the Northwestern Tunisia. This work aims at studying the insecticidal activity of essential oils of Cupressus arizonica and C. sempervirens on 3rd, 4th and 5th instars larvae of T. viridana by the contact test. Three different concentrations of essential oils (0.05%, 0.1% and 0.5%) were used to test their contact effectiveness; the Deltamethrin and the ethanol were used as positive and negative controls. Larvicidal activity was determined by measuring the Mean Mortality Time (MMT) to kill 100% of larvae. A total of 28 chemical compounds have been identified from C. arizonica and 20 chemical compounds from C. sempervirens. The difference in MMT of the 3rd instar larva was highly significant between the 3 concentrations of the two tested essential oils, the negative and positive controls. In fact, the concentration (0.5%) was more efficient than the two other concentrations with a MMT=1h31min12s for C. arizonica and 5h11min20s for C. sempervirens. The same results were observed for the 4th (MMT=3h23min24s (Ca) and 4h1min (Cs)) and 5th (MMT= 3h23min24s (Ca) and 4h01min (Cs)) instars. The results revealed that the essential oil of C. arizonica was more effective than C. sempervirens. Therefore, it is recommended to use the essential oil of C. arizonica and not that of C. sempervirens, given its insecticidal efficiency on the 3rd instar larva of T. viridana

Tortrix Moths (Lepidoptera, Tortricidae) of Grafskiy Park and agrobiostation of M. Gogol Nizhyn State University (Chernigiv region, Ukraine)

An annotated list of tortricid moths (Lepidoptera, Tortricidae) of the Grafsky Park and the agrobiostation of the Nizhyn Mykola Gogol State University is given for the first time. In total, from 1987 to 2018, 95 species of 13 tribes were identified in the studied area: Tortricini – 6 species, Cochylini – 12 species, Cnephasiini – 7 species, Archipini – 12 species, Sparganothini – 1 species, Endotheniini – 4 species, Bactrini – 2 species, Olethreutini – 12 species, Lobesiini – 1 species, Enarmoniini – 6 species, Eucosmini – 22 species and Grapholitini – 9 species. It is about 40% of the species diversity of tortricid moths of Chernihiv region known now, and about 17% of the fauna of Ukraine. The distribution and biology of the recorded species are analized. Herein 54 species of tortricid moths are recorded for Chernihiv region for the first time, 34 species (Tortrix viridana, Aleimma loeflingiana, Acleris holmiana, A. forsskaleana, Eupoecilia ambiguella, Archips podana, A. crataegana, A. xylosteana, Choristoneura diversana, Argyrotaenia ljungiana, Ptycholoma lecheana, Pandemis corylana, P. cerasana, P. heparana, Syndemis musculana, Adoxophyes orana, Apotomis betuletana, Orthotaenia undulana, Hedya salicella, H. nubiferana, H. pruniana, H. ochroleucana, Ancylis achatana, A. mitterbacheriana, Spilonota ocellana, Gibberifera simplana, Epinotia nisella, Notocelia uddmanniana, Cydia pomonella, C. pyrivora, C. fagiglandana, C. splendana, C. amplana, Grapholita funebrana) are known as pests of deciduous trees and 4 species (Piniphila bifasciana, Gravitarmata margarotana, Rhyacionia buoliana, Cydia strobilella) are known as pests of coniferous trees.

Rzecz o stanie zdrowotnym lasów olsztyńskich

Las jako zespół przyrody o określonych właściwościach pełni szereg wielorakich funkcji gospodar­czych, pośrednio gospodarczych i pozagospodar­czych (funkcje gospodarcze wynikają z faktu, że las jest przede wszystkim bazą produkcyjną drewna i tzw. leśnych użytków ubocznych, pośrednio gospo­darcze polegają na kształtowaniu równowagi biolo­gicznej w środowisku przyrodniczym - wpływ drzewostanów na klimat lokalny, warunki glebowe i sto­sunki wodne jest bezsporny, a pozagospodarcze wynikają z pełnionej roli w kształtowaniu krajobrazu). Jako przyrodnicza całość jest mało stabilny i ulega wielu czynnikom biotycznym, abiotycznym i antropogenicznym. Z praktyki ochrony lasu w granicach admini­stracyjnych Regionalnej Dyrekcji Lasów Państwo­wych w Olsztynie wynika, że szczególnie niebez­pieczne bywają owady - z grupy szkodników pier­wotnych - żerujące na drzewach żywych i pozornie zdrowych, a osłabionych działaniem jednego lub kil­ku czynników, zwykle abiotycznych. Pojawy nie­których zmuszają do podejmowania zabiegów ratow­niczych. Sposoby sprowadzania liczebności trzech moty­li, tzn. brudnicy mniszki (Lymantria monacha L.), strzygoni choinówki (Panolis flammea Schiff.) i zwójki zieloneczki (Tortrix viridana L.), do poziomu przed laty nazywanego „żelaznym zapasem” przedstawia niniejsze opracowanie.

PECULIARITIES OF TORTRIX VIRIDANA L.ECOLOGY IN CONDITIONS OF CENTRAL FOREST-STEPPE

Green oak tortrix (Tortrix viridana L.) occupies a leading position in the leaf-biting pests of English oak (Querqus robur L.). Full-scale research on permanent test plots in the oak groves of the Voronezh Region and laboratory experiments at the Department of Ecology of VSUFT has revealed that the exit of the larvae of green oak tortrix is synchronized with the opening of the buds of the early form of the oak tree, and larvae have a regional specificity. Caterpillars of the first ages of green oak tortrix both in field and laboratory conditions show themselves as strict monophages, and caterpillars of the 5th age are facultative polyphages. For normal hatching of larvae, reactivation with low temperatures is necessary, followed by a set of effective temperatures of more than 1,750 ° C. At the same time, temperatures below -30 ° C for 3 days or spring frosts below -60 ° C lead to the death of oviposition. The speed of movement of the newly born caterpillars of green oak tortrix is 16 cm per minute or 9.6 m per hour, that is, during the active period, the newly born caterpillar can overcome 30-60 meters in search of food. The range of variation in the width of the head capsules of larvae of all 5 ages has been determined. The duration of the period of pre-fast fasting and sleep in older caterpillars varies considerably (2 = 0.709)but has a rather close correlation with the absolute weight of caterpillars (r = 0.587). The duration of the pupal stage is 7-13 days. In laboratory conditions, at a temperature of 220 ° C, the first butterflies fly out after 5 days. In nature, the flight of butterflies coincides with the flowering of jasmine, white acacia, black elderberry. The first males fly out and the females fly out only after 2-3 days. Mass flying begins 4-5 days after the appearance of the first butterflies. The butterflies’ outflying lasts 8-12 days, and they can be found in plantation for 16-28 days. From the entomophages of green oak tortrix, riders Phytodietus polizonias Forst., and on the puppies Phaeogenes invisor Thunb. Apechtis rufata Gm. Hoplectis maculator F. has been noted. The tahin Elodia tragica has been also found on the pupae. Trichogramma evanescens Weit. and Trihogramma embryophagum Htg. have been noted as the main ovaries of green oak tortrix

Monitoring infestations of oak forests by Tortrix viridana (Lepidoptera: Tortricidae) using remote sensing

We tested the suitability of Landsat images to track defoliation by insect herbivory with focus on the oak leaf roller, Tortrix viridana (Lep.: Tortricidae). Landsat images from the period before (2002) and after the T. viridana infestation (2007, 2014) were compared in oak forests of Zagros in western Iran. The Normalised Difference Vegetation Index (NDVI) was calculated for the test area from Landsat 5, 7, and 8 images. Because the red and near-infrared spectral bands of Landsat 8 OLI sensors are different from the other two, a model for the calibration of Landsat OLI NDVI was developed. The proposed model with a correlation coefficient of 0.928 and root mean square error of 0.05 turned out to be applicable and the NDVI decreased significantly during the observation period. Taking into account the protection status of the area and small fluctuations in temperature, the decrease in NDVI could be attributed to T. viridana damage.

Effects of various host plants on nutritional indices and some biochemical compounds in green oak leaf roller, Tortrix viridana L. (Lepidoptera: Tortricidae)

The green oak leaf roller, <em>Tortrix viridana</em> L., is one of the most destructive pests, causing damages to various species of oak, feeding on different host plants including <em>Quercus infectoria</em> Oliv, <em>Q. branti</em> Lindl, and <em>Q. libani</em> Oliv. Nutritional indices, activity of enzymatic and non-enzymatic compounds of <em>T. viridana</em> were studied under laboratory conditions. In addition, chemical components were analysed in the leaves of the three host plants. Fourth instar larvae reared on <em>Q. branti </em>showed the highest values of relative consumption rate (RCR), approximate digestibility, and consumption index (48.73±6.22; 90.45±1.06 and 97.45±12.44 respectively), while the lowest values were observed on <em>Q. libani</em>. Efficiency of conversion of ingested food in the fourth instar larvae was the highest (3.17±0.661) on <em>Q. libani</em> and the lowest (1.53±0.164) on <em>Q. branti</em>. The fifth instar larvae fed on <em>Q. libani</em> had the highest RCR (15.64±2.51). The highest amounts of triglycerides, uric acid, glucose, protein and the lowest activity of alkaline phosphatase were observed in the fifth instar larvae reared on <em>Q. libani</em>. The leaves of Q. libani highlighted the highest amounts of total nitrogen, total protein, water, potassium, magnesium and total carbohydrate. The present research suggested that the nutritional quality of the host plants have crucial effects on <em>T. viridana</em> larvae.