Quadraspidiotus Perniciosus Research Articles (Page 1)

Evaluating cultivar susceptibility to biotic stressors in apple orchards is essential for selecting genotypes adapted to local conditions and for designing effective plant protection strategies. This study conducted a comparative assessment of five apple cultivars (‘Florina’, ‘Jonathan’, ‘Golden Delicious’, ‘Pinova’, and ‘Idared’) in response to major fungal diseases (Venturia inaequalis, Podosphaera leucotricha, and Monilinia spp.) and insect pests (Eriosoma lanigerum, Quadraspidiotus perniciosus, Anthonomus pomorum, Aphis spp., and Cydia pomonella). The cultivars were monitored over a five-year period in six orchards located in Central Transylvania, Romania. Significant differences in phytosanitary behavior were recorded among cultivars and locations. ‘Florina’ consistently showed the highest tolerance to pathogens and pests across all sites and years, while ‘Jonathan’ and ‘Golden Delicious’ proved highly susceptible, particularly to apple scab, powdery mildew, aphids, and codling moth. Pest incidence was strongly influenced by temperature, while disease occurrence was more closely linked to precipitation patterns. Heritability analysis indicated that genetic factors played a substantial role in shaping cultivar responses to most biotic stressors. The integrated approach to cultivar–location–pathogen and pest interactions offers practical insights for optimizing orchard protection strategies under variable ecological conditions.

Goal. Determination of optimal methods of phytosanitary monitoring and strategies for controlling the number of harmful arthropods based on ecologically safe preparations on ornamental crops in urban green areas. Methods. Monitoring of the phytosanitary state of urbophytocenoses was carried out by the method of route surveys of plantations. The method of visual detection of the phytophagous or traces of its vital activity on the trunk, branches, shoots and leaves was used to examine the crown of plants. To record the density of phytophagous colonies and to identify species, individuals were collected using a transparent adhesive film. Colored glue traps were used to monitor Lepidoptera, Diptera, Coleoptera and other insects. Results. The use of colored glue traps in the closed soil of the Botanical Garden named after Acad. O.V. For the purpose of monitoring insects, Fomina made it possible to identify 16 species of phytophages from 4 orders: aphids (Aphidoidea) Myzus persicae Sulz., Macrosiphum rosae L., Idiopterus nephrolepidis Davis.; coccids (Coccoinea) Nipaecoccusnipae Mask, Pseudoccus longispinus (Targioni Tozzetti), Coccus hesperidum L., Diaspis boisduvalii Sign., Kuwanaspis pseudoleucaspis Kuw.; whiteflies (Aleyrodoidea): Aleurodes vaporariorum Westw., Bemisia tabaci Genn., B. argentifolii Bellows; thrips (Thysanoptera): Thrips tabaci Lind., Heliothrips haemorrhoidalis Bouche., Frankliniella occidentalis Pergande, Echinothrips americanus Morgan, Thrips palmi Karny. Among the seven colors we used to determine the degree of attractiveness of insects that are common in indoor soil, the most attractive color is yellow. Using color traps in open ground to monitor species such as Phyllonorycter issikii Kumata (a plant pest of Tilia L.) and Cameraria ohridella Deschka & Dimic (a plant pest of Aesculus L.) showed that three colors were most attractive to these species: blue, green and red. A high level of effectiveness of the drug Phytocomplexon-1 has been established in comparison with other options. For the pests Quadraspidiotus perniciosus, Hyphantria cunea and Cydalima perspectalis, this drug showed the highest efficacy rates ranging from 79.5 to 92.4%. Conclusions. The use of colored glue traps in closed and open ground conditions is an important element for insect monitoring. It is important to consider the color of traps when planning strategies for monitoring and controlling plant pests, which can improve the effectiveness of plant protection measures. The high level of effectiveness of new environmentally safe preparations based on rapeseed oil and plant extracts against various types of harmful organisms has been confirmed. In particular, the drug Phytocomplexon-1 proved to be the most effective for insects. The study indicates the prospects of using environmentally safe methods of plant protection in botanical gardens and megacities.

Scale lice have attacked apple fields in 8 villages in Bumiaji District, Batu City, namely Giripurno, Tulungrejo, Pandanrejo, Sumbergondo, Bulukerto, Punten, Gunungsari, and Bumiaji villages since 2005. Knowledge of the biological aspects of this pest can be done using sticky bands. This is aimed at controlling pests. Determination of sample plants was carried out systematically as many as 18 sample plants on manalagi apple (Malus sylvestris). The sample plants were apple plants that were attacked by scale lice. The type of adhesive treatment was adjusted to the variation of position (east, west, central) and research height (1m and 1.5m). The results obtained were that the pest found was Diaspidiotus perniciosus and the natural enemy found was Encarsia strenua. The part that has the most attacks is the stem/twig. The eastern branch with a height of 1.5 m has a higher even distribution of scale lice than the other parts. The highest dominance index (C) of scale lice of 0.29 was obtained by the middle-adhesive treatment of height 1m or rootstock. The pattern of population distribution based on sticky bands is random and tends to be individualistic.
 Keywords: apple plant, diaspididae, scale lice

Apple is attached by number of insect pests, among them San Jose Scale (Quadraspidiotus perniciosus) is key pests. San Jose scale (SJS) attacks temperate fruit crop in the state of J&K. It sucks sap from, twigs, branches, and fruits, weakens the plant and the fruits having scale infestation is rendered unthrifty and unmarketable. The pest causes great loses to apple in quantity and quality and debilities apple tree by vigour and health. The objective of this study was to examine efficacy of HMOs as dormant sprays at different concentrations to manage San Jose scale (Quadraspidiotus perniciosus Comstock) and two insecticides viz Chlorpyriphose 25EC and Dimethoate 30Ec at different concentrations were checked for their bio-efficacy in same orchard in late spring during 2021-22. On the basis of pooled data for years for revealed that highest cumulative mean mortality (79.48%) was recorded with the application of Bal spray at concentration of 2.5% followed by 77.56%. mortality of SJS @ 2.5% concentration by HP oil. Chlorpyriphose recorded 71.98% pooled mean mortality at 0.03 5 concentration.

The long-term analysis of the entomocomplex of plum orchards, carried out in Krasnodar Territory, revealed variations in the quantitative composition of entomofauna of harmful species and the level of their harmfulness. It was established that, in the period from 2005 to 2021, the rotation of dominant and secondary species occurred. The main species included plum Grapholitha funebrana Treitschke and oriental Grapholitha molesta Busck fruit moths, plum black Haploca minuta Christ. and yellow Hoplocampa flava L. sawflies, plum aphid Hyalopterus pruni Geoffr. and twospotted spider mite Tetranychus urticae Koch. Associated species included plum gall Acalitus phloeocoptes (Nal.) and hawthorn Tetranuchus viennensis Zacher. mites, fruit-tree Tibicina haematodes Scopoli and citrus flatid Metcalfa pruinosa (Say) planthoppers and leaf roller moths of Tortricidae family. The group characterised by a limited distribution area includes the Californian Quadraspidiotus perniciosus Comst. and Turanian Diaspidiotus prunorum Laing. scales, plum Sphaerolecanium prunastri Fonsc and European brown Parthenolecanium corni Bouche. scales, seed wasps Eurytoma amygdali End., brown marmorated stinkbug Halyomorpha halys (Stål) and secondary insects (unequal bark beetle Xyleborus dispar F., fruit tree bark beetle Scolytus rugulosus (P.W.J. Müller), wood leopard moth Zeuzera pyrina L). When considering the structure formation of phytophage complex according to phylogenetic specialization, taking into account trophic relationships, it was established that the proportion of polyphages is 2.5 times higher than that of oligophages and 8.5 times higher than that of monophages from the total number of registered pest species. In the past decade, a reduction of pesticide load in plum agrocenoses has been observed due to the wider use of agrotechnical methods and the inclusion of bioregulatory and biological insecticides into protection systems, which contributed to the preservation and increase of beneficial fauna. Entomophages constitute 7–10% of the total number of entomoacrocenosis dominated by Hymenoptera and Coleoptera classes and mites of Acari subclass. The long-term monitoring of species composition, rotation of dominant and secondary pest species and entomophages, variations in their number and harmfulness, seasonal dynamics, trophic relationships of plum entomoacrocenosis under varying environmental conditions and increasing intensification of agricultural production expand the possibility of phytosanitary optimisation strategy of perennial agrocenoses in the south of Russia. This contributes to the preservation of regional biodiversity, as well as to the stable production of high-quality ecologically safe products with minimal negative impact on the environment.

Degree day-based management of San Jose scale (Quadraspidiotus perniciosus) by horticulture mineral oils (HMOS) at dormant stage in apple orchards of Kashmir

Field efficacy of horticulture mineral oil Rilso 999 and MAK All Season at different concentrations were evaluated at two locations i.e., Lar (District Ganderbal) and Hajin (District Bandipora) of J&K during 2017 and 2018, all the treatments were significantly superior in terms of mortality of San Jose scale Quadraspidiotus perniciosus (Comstock) (SJS) and European red mite (ERM) Panonychus ulmi (Koch) as compared to untreated control. The cumulative mean mortality of SJS (58.08% and 62.20%) and ERM (58.69% and 53.65%) at recommended dose of 7.5 ml/ l of water both for standard check (MAK All Season) and Rilso999, respectively. Maximum (27.14 and 19.63 %) cumulative mortality of Amblyseius spp. and Coccinellids were recorded with Rilso999@ 10 ml/ l of water, respectively. No phytotoxicity symptoms viz., leaf injury, yellowing, wilting, necrosis, hyponasty and epinasty were observed with Rilso999 at 15 ml/ l of water. Maximum yield (246.16 kg/tree) was attained with MAK (standard check) @7.5 ml/ l of water.

A two year field trial at Shalimar campus, SKUAST-Kashmir was conducted to study the compatibility of various insecticides and fungicides against major pests and diseases of apple. Insecticides and fungicides are recommended to be sprayed separately without admixing suspensions involving huge labour and time components. Different pesticides and fungicides were sprayed with at five different phenological stages (fruit-let, fruit development stage-I and fruit development stage II). Standard controls comprising of recommended sprays were also given at these stages for comparison, in addition to unsprayed check. Observations with respect to foliage and fruit scab, Alternaria leaf blotch and percent mortality of European red mite (ERM) and San Jose Scale (SJS) were recorded at fruit-let, fruit development stage-I and fruit development-II stages. The pesticidal combination exhibiting physical incompatibility was discarded in the initial phase. Combined spray of fungicide and insecticide proved equally effective in controlling diseases and pests of apple in different stages. The experimental plants sprayed with mixtures of fungicides and insecticides at recommended concentrations exhibited significant reduction in apple scab, ALB, EMR and SJS in comparison to unsprayed check at fruit-let stage. Results revealed that treatment T5 (difenconazole + phosalone) proved superior in minimizing foliar scab incidence and intensity whereas treatment T3 (difenconazole + chlorpyriphos) and T16 (difenconazole) had minimum incidence (0.80%) and intensity (0.30%) of fruit scab. The trees sprayed with hexaconazole followed by chlorpyriphos (T9) result lowest disease incidence (0.23) of ALB and lowest intensity (0.17) was found in Haxaconozol followed by Milbactin (T10). T4 (Difenconazole + Milbactin) proved most effective in inflicting maximum ERM mortality (68.6%) and was at par with T7 (65.6%) followed by T14. Treatment T1 (Haxaconozole + Milbectin) shows 57 per cent mortality of SJS and was at par with T3 (Difenconazole + Chlorphriphos) and T12 (Chlorpyriphos) treatments. At fruit development stage-I, all the treatments controlled apple scab, ALB, ERM and SSJ significantly as compared to unsprayed check (table 2). T5 (Zineb +Chlorpyriphos) had least foliage scab incidence (2.63%) and T13 (Mancozeb) showed lowset intensity (0.70%), whereas T5 (Zineb + Chlorpyriphos) exhibited least fruit scab incidence (6.50%) followed by T8 (Mancozeb followed by Chlorphriphos) and lowest intensity were recorded in T2 (Mancozeb + Chlorpyriphos) and T8 (Mancozeb followed by Chlorphriphos) (02.03%). ALB incidence was significantly controlled by T3 (Mancozeb + Dicofol) and intensity was significantly controlled by T1 (Mancozeb +Quinalphos) followed by T2. Percent mortility of ERM was highest by T12 (Dicofol) (80.4 %) followed by treatment T5 (Zineb + Chlorpyriphos) (75.9) per cent. In case of SJS, treatment T10 (Quinalphos) and T7 (mancozeb + Quinalfos) was most promising with 79.3 and 78.3% mortality, respectively. At fruit development II, all the treatments significantly controlled apple scab, ALB, ERM and SJS in comparison to unsprayed check (table 3). Least leaf scab incidence and intensity was showed by treatment T5 Bitertinol+ Propargite (8.63 and 2.41 %, respectively) However, least fruit scab incidence was observed in trees sprayed with T3 (Flusilozole + Summer spray oil) while treatment T2 (Flusilozole + Propargite) showed lowest fruit scab intensity of 3.27 per cent. Bitertinol + summer spray oil (T6) sprayed trees had least ALB incidence (5.97%) while T7 (Difenconazole + Dimethoate) had least ALB intensity (2.65%). Percent mortility of ERM was highest by T14 Propargite effectively controlled ERM and was at par with treatment T15 and T8. Similarly In case of SJS treatment T7 (Difenconazole with Dimethoate) and T1, T4, T6, T9, T10 and T13 showed statistically similar performance. Thus compatible chemicals can effectively minimize labour, time and inputs.

In order to identify the main pests of seed orchards, as a result of observations on apple, beech and pear orchards on farms in Tashkent region, 3 genera Lepidosaphes, Diaspidiotus and Parlatoria belonging to the family Diaspididae were recorded in orchards. They were found to be distributed in 3 species Lepidosaphes ulmi (Linnaeus, 1758), Diaspidiotus perniciosus (Comstock, 1881) and Parlatoria oleae (Colvée, 1880) from the family Diaspididae, and 2 were recorded as dominant species. In order to create a species composition and GIS map of the Diaspididae family in seed orchards, 12 coordinates of pests in apple, quince and pear orchards were determined and a GIS map was constructed.

Studies of the dynamics of changes in the species composition of pests in fruit orchards in the context of climate change became especially relevant. Monitoring of phytophagous insects in gardens with the isolation of dominant species is a key component for building an effective system of protection of perennial plantings. The study was conducted in 2018-2020 on the basis of the Melitopol Experimental Station of Horticulture named after M.F. Sidorenko IS NAAS. The purpose of the study was to establish the species composition of phytophages and the level of their colonisation of peach orchards to optimise measures to protect this crop from pest damage. Conducting route and detailed surveys in different phases of tree development (swelling of buds, pink bud, flowering, end of flowering, forming, growth and ripening of fruits) showed that the entomocenosis of peach orchards consisted of 15 species of phytophagous insects belonging to 4 orders, 10 families, and 2 species of mites. The species composition and level of pest colonisation of peach orchards changed under the influence of weather conditions and protection measures. Lepidoptera insects were represented by 7 species of pests, among which the main carpophages were Grapholitha molesta Busck., to a lesser extent Anarsia lineatella. The attack density of these pests each year was at a high and medium level, respectively. Throughout all the years of study most harmful of insects from the order Coleoptera was polyphagous Epicometis hirta. The main Homoptera pest in 2018 was Quadraspidiotus perniciosus Comst., while the prevalence of other catfacing insects was weak. During the vegetation periods of 2019-2020 the development of insects such as aphids and increase in the colonisation of leaves by mites, Thrips fuscipennis Haliche and Typhlocyba rosae L. was recorded in peach orchards

The field experiment, conducted with the objective of examining the efficacy of different concentrations of two oil dormant sprays of Arbofine extra along with standard check (ATSO) to manage san jose scale (Quadraspidiotus Perniciosus Comstock) in delayed dormant season of 2015-16, revealed highest comulative mean mortality of SJS (82.69%) with the application of 2.5 per cent of Arbofine extra followed by 80.71 per cent mortality of SJS with 2.0 per cent of Code-204 as against the standard check (ATSO) applied at 2.5 per cent concentration (80.12%) and the lowest (76.47 per cent) at 1.5 per cent concentration. Two parasitoids, Encarsia pernicious and Aphytis proclia and one predator Chilocorus infernalis were found on SJS twigs from the treated area. Arbofine extra @ 2.5 per cent concentration recorded mean yield (10.0 boxes) of ‘A’ grade followed by 8.33 boxes @ 2.0 per cent concentration.

Goal. Analysis of the latest methods for identifying pests of an orchard using pheromone monitoring and factors affecting its implementation.
 Methods. The studies were carried out in accordance with modern methodological approaches to pheromone monitoring of pests of fruit plantations.
 Results. The principles of pheromone monitoring in an orchard are given to identify harmful and quarantine organisms, which makes it possible to obtain information about the presence of pests in a certain area, determine their number, development dynamics, and, on the basis of the data obtained, plan and carry out appropriate phytosanitary measures. The main pests of the orchard of the Lepidoptera and Hemiptera classes have been identified, monitoring of which is carried out using pheromone traps. Methodological recommendations are given for conducting pheromone monitoring in fruit plantations to identify the eastern fruit moth (Grapholitha molesta Busck), Californian and mulberry scale insects (Pseudaulacaspis pentagona Targ.-Tozzetti, Quadraspidiotus perniciosus Comst), American white butterfly (Hyphantria cune). The advantages of the pheromone method over other monitoring methods are presented. The main factors that affect the catch of pests with pheromone traps are described.
 Conclusions. The information obtained with the help of pheromone traps is a component of effective programs — systems of integrated plant protection against pests, which combine the use of a complex of biological, chemical, agrotechnical measures, as well as fundamental for planning measures to prevent emergencies in a phytosanitary state. The informativeness and reliability of pheromone monitoring makes it possible to substantiate and develop instrumental monitoring technologies that reduce the number of chemical treatments by up to 30%, increase labor productivity by 75%, reduce costs by 70%, and increase the efficiency and reliability of accounting.

Goal. Study of the entomocomplex of peach plantations in order to plan appropriate measures to limit their harmfulness.
 Methods. Laboratory field. The population of peach trees by pests was determined according to generally accepted methods in the Research Garden of the Dmytro Motorny Tavriya State Agrotechnological University. Census counts were conducted in peach plantations of the Crimean Fireworks, Jubilee Sidorenko, Redhaven, Skazka, Vireney and Ambassador of Peace varieties.
 Results. It was found that in the agrocenosis of peach plantations during 2018—2019, three permanent species of pests were registered: California thymus (Quadraspidiotus perniciosus Comst.), Turkestan mite (Tetranychus turkestani Ud. Net Nik.) And eastern fruit eater (Grapholitha molesta Busck). The adult age of the last phytophagous began with the beginning of flowering peach trees and lasted until September. The number of butterflies in pheromone traps varied during the growing season from 24.7 to 48.5 specimens / trap, ie significantly exceeded the economic threshold of harmfulness. It should be noted that despite the very high age of the pest in the experiment, damage to peach shoots in all varieties (except Crimean fireworks and the Ambassador of Peace) was below the economic threshold of harmfulness (0.1—1.0%). The population of peach leaves by Turkestan mite on different varieties was 0.1—1.5 specimens / leaf. Studies on the peculiarities of the development of the Californian thyroid have shown that the beginning of the flight of males of the first generation was recorded in pheromone traps in the second decade of May. In 2019, this phase of development is marked a week later. The revival of traveling larvae also occurred at different times, with slight fluctuations. The number of California thyme on peach varieties ranged from 0.8 to 17.2 specimens / shield.
 Conclusions. On peach cultivars the California thyme (up to 17.2 specimens/shield), oriental fruit fly (from 0.3 to 2.5 specimens/shoot) and Turkestan spider mite (up to 23.8 specimens / leaf) were noted, depending on The high potential of California thyme reproduction in peach plantations on the Crimean Fireworks, Virenea and Ambassador of Peace varieties has been recorded.

Innovative plant protection means prepared natural raw materials

Twelve species belonging to different families of Hemiptera viz. Aphididae (Eriosoma lanigerum Hausmann, Aphis pomi De Geer), Reduvidae (Reduvius delicatula Distant), Dictyopharidae (Putala rostrata Melichar), Diaspididae (Quadraspidiotus perniciosus Comstock), Pentatomidae (Nezara viridula (Linnaeus), Halyomorpha halys Stal, Halys dentatus Fabricius, Scutelleridae (Chrysocoris purpureus Westwood), Fulgoridae (Borysthers sp.), Jassidae (Empoasca sp.) and Membracidae (Oxyrachis rufescens Walker) have been reported infesting apple plantations from different apple growing districts viz. Bhaderwah, Batote, Kishtwar, Udhampur, Poonch and Rajouri districts of Jammu province of Jammu Province. Their distribution, host plants, diagnostic features and damage caused by these pests to apple plantations are also discussed in the present paper.

Scale insects are sap feeders, causing threat to the cultivation of several fruit crops. The scale insects can be grouped into two broad categories. The first group belonging to family Diaspidide, comprises many species of armoured scales (hard scales) belonging to the genera. <em>Aonidiella, Aulacaspis, Pseudaulacaspis, Hemiberlesia, Aspidiotus, Chrysomphalus, Pinnaspis, Parlatoria</em> etc. The second category belonging to family Coccidae comprises of the soft scales belonging to the genera Coccus, Puvinaria, <em>Chloropulvinaria, Saisettia, Parasaisettia, Vinsonia, Drephanococcus, Ceroplastes, Ceroplastodes</em>, etc. Scale insects are highly polyphagous, but certain species cause severe damage to specific fruit crops viz. the red scale, <em>Aonidiella aurantii</em> (Maskell) on citrus; latania scale, <em>Hemieberlesia lataniae</em> (Sign.) on grapevine.; white scale, <em>Aulacaspis tubercularis</em> (Newstead) on mango; green shield scale, <em>Pulvinaria psidii</em> (Maskell) on guava, lemon and sapota, <em>Pulvinaria polygonata</em> (Ckll.) on mango; green scale <em>Coccus viridis</em> (Green) on citrus and sapota and <em>Drephanococcus chiton</em> (Green) on ber and guava. Insecticides are not effective due to the presence of protective cover over the scales. On the other hand, scale insects are more amenable for biological control due to their sedentary habit and colonial distribution. Several scale insects are well regulated by the local predators. In nature, green shield scale, <em>Pulvinaria psidii</em> (Maskell) is kept under check by the predator, Australian ladybird beetle <em>Cryptolaemus montouzieri</em> Mulsant on guava, sapota and lemon. The reduction of the mango green shield scale <em>Pulvinaria polygonata</em> was attributed mainly to the action of the predators <em>C. montrouzieri</em> and <em>Spalgis epeus</em> Westwood. The green scale <em>Coccus viridis</em> on acid lime and white scale <em>Aulacaspis tubercularis</em> on mango are well regulated by the coccinellids <em>Chilocorus nigrita</em> (Fab) and <em>C. circumdatus</em> Sch. Local parasitoids are also known to effectively check the populations of the scale insects on different fruit crops. The encyrtid <em>Anicetus ceylonensis</em> How and the pteromalid <em>Cephaleta brunniventris</em> Motsch are responsible for the suppression of wax scale <em>Drephanococcus chiton</em> on ber and guava. The aphelinid parasitoid, <em>Pteroptrix koebeli</em> How. plays a major role in the regulation of the mango scale <em>Aulacaspis tubercularis</em>. On sapota, the aphelinid parasitoid <em>Coccophagus</em> sp. was the dominant natural enemy causing up to 95 % parasitism. <em>Scutellista cyanea</em> Motsch. (Pteromalidiae: Hymenoptera) was able to suppress <em>Parasaissetia nigra</em> (Nietner) on custard apple and pomegranate. In the absence of effective biocontrol agents in nature, parasitoids and predators have to be released in the field for obtaining an effective and quicker suppression of the scale insects. Release of adult <em>C. nigirita</em> was found to be effective in the control of the red scale on citrus in Karnataka, Andhra Pradesh and Punjab. Release of <em>C. infernalis (C.bijugus)</em> Mulsant @ 10-20 beetles/tree once in April-May has also been recommended to reduce Sanjose scale. The white halo fungus, <em>Lecanicillium (Verticillium ) lecanii</em> can be sprayed at 16 x 10<sup>6</sup> spores/ml along with 0.05% of sticking agents in the evening hours at 15 days interval to control the green scale in the hilly areas during cooler months. The biocontrol agents can be integrated with plant origin insecticides as they do not affect the activity of these agents.

During 1986-1988 the relationship between catches of San Jose scale (SJS), Quadraspidiotus perniciosus (Comstock), adult males in pheromone traps and crawlers on sticky-tape traps was studied as a basis of SJS crawler control in apple orchards of Northern Greece. Spring male flight began in mid-to late April and crawler emergence occurred in mid-to late May. Crawlers were active for a period of 6-7 weeks until early July. Peak crawler emergence occurred approximately 12 days after the first emergence, or 42 days after the first males were captured on pheromone traps. Because in our 3-year study the crawler emergence occurred 29-31 days or 191-202 day-degrees (base 10.5°C) after the capture of the first male, we conclude that a consistent time-relationship exists between the two events. Two insecticide treatments, one three days after the first crawler appearance and another 10 days later (near peak crawler activity), provided the best control against the first generation of scale.

During the 1982-1985 period the aphelinid endoparasite Encarsia perniciosi Tower was captured on synthetic pheromone traps of the San Jose scale (SJS), Quadraspidiotus perniciosus Comstock, in scale-infested insecticide treated and untreated orchards of Central and Western Macedonia (Northern Greece). It has expanded especially near the sites where it had been released, but also in areas 50-100 km from the point of release. The parasite in untreated orchards generally appeared from April to October, while in orchards treated with insecticides it was not caught after mid June. Spring flights of the parasite occurred on almost the same dates as the first captures of the male scale. Subsequent flights of E. perniciosi were not always synchronized with those of the male scale, and after the beginning of June the parasite showed a general decline throughout the remainder of each season. The pheromone of the scale insect acts as a kairomone to the parasite and it can be used in trapping systems in scale-infested orchards for the confirmation of the presence and the dis­tribution of E. perniciosi.

The seasonal flight of San Jose scale (SJS), Quadraspidiotus perniciosus Comstock, males was studied during 1984-1987 in peach and nectarine orchards, under two different climatic conditions in Central Macedonia (Northern Greece), using sex pheromone traps. In late-season regions there were three periods of male flight activity (May, July-August, September – October), while in early-season regions there was also a partial fourth one (mid April-May, mid June-July. August – mid September and late September – early November). In the latter regions these flights can be correlated with the appearance of the scale crawlers during three periods (late May – early July, mid July – August, September – October) and a partial fourth one (November) in milder years, as determined using the sticky-tape trap technique. Pheromone traps and sticky-tape traps can be used for the study of phenology of San Jose scale, under conditions prevailing in Northern Greece.

Sampling results during 1978-1979 and 1981-1982 in two heavily-infested almond orchards in Northern Greece showed a high mortality of the San Jose scale. A considerable part of this mortality was attributable to indigenous entomophagous insects, especially predators. Among them, Cybocephalus fodori Endrody-Younga (Coleoptera: Nitidulidae) appeared to be the key species. Field observations showed that C. fodori hibernates as an adult, forming aggregations. C. fodori reared in outdoor cages showed full adult activity by end March. Given an abundant supply of prey, the insect develops two complete and a third partial generations per year. Under constant conditions (25±2° C, 65±5% R.H. and 16 hrs light per day), the development of its three larval instars was completed in about 19 days and the pupal stage lasted about 10 days. On average, 68 Quadraspidiotus perniciosus Comstock (Homoptera: Diaspididae) adult females were partly consumed per larva of C. fodori. Individually deposited eggs and young larvae were found under the covers of the San Jose scales.