The More Important Injurious Pests of , Stone , and Grapes in Arab Countries and Means of Reducing Their Injury A.S. Talhouk Faculty of Agricultural and Food Sciences, American Universitv of Beirut Beirut. Lebanon

-{bstract Talhouk, A.S..l989.The more important injurious pesrsof citrus, stone fruits,and grapes in Arab countries and means of reducing their injury. Arab J. Pl. Prot. 7: 200- 198.

The favourable climate in most Arab countries for the phytophagous insects of the said fruits found favourable mic- growth of fruits resulted in the creation of extensive mono- ro-climates and biotopes that helped them reach pest status. cultures of citrus, stone fruits and grapes whose fruits are Biological information relative to management of the phy- consumed fresh. canned or exported. As a consequence, tophaga in order to reduce their damage was given.

I. Introduction hand, there are the xylophagous insects whose optimal larval The application of integrated pest management (IPM) to requirements are weak woody stands in which they can bore orchards and vineyards can only succeed where the correct their tunnels witho.ut resistance on the parts of a (weak) information related to the following are available: (1) the wood. Finally,, a number of other plant feeders are less physiological requirements of the plants to be protected (2) choosy. and can adapt to their host plants practically as long the identity of the local phytophagousspecies(3)the phenolo- as the latter are alive; the majority of chewing insects, with gy of both of the plants and their enemies (4) elements of some variation, fall into this category. Although plants can ecology, because agriculture is a true against the collapse of an attacked plant. A the collectir.; and proper identification of all in second safety factor which has a great survival value to the the country, more or less along the pattern of what is already plants is the protection of natural enemies of its phytophaga, done in the Fauna of Saudi Arabia, and, to a lesser degree, including birds, arthopods, and pathogens that gradually ar- in Oman. Kuwait,, Egypt and Iraq. The faunas of adjacent rive to settled environments, such as orchards, woods, and countries are not necessarily identical. The application of the forests. However, since phytophagus arthropods arrive to proper pesticides to control a pest is very likely to fail if the newly planted orchards a considerable time before their timine of the application is incorrect. natural enemies (Volterra's Third Law), it is often necessary Althoueh foreign text books on pest control are basically to use pesticides when phytophagous populations start to en- ver)' helptul in principle. less than three percent of the agri- dager their host plants. When such necessity becomes un- cultural pests of USA. and less than 13 percent of those in avoidable, the use of selective pesticides, in spite of their West European countries erist in the \tiddie East. high prices. is the onlv long term advisable resort. Although In integrated pest managemenl. a number of facts har.e to the contact or general purpose pesticides are cheaper and be considered in order to attain satisfacton' results. Fcrr er'- ma) shou immediate. spectacular results following their ap- ery plant species. there are anhoprods that feed on it s hrrse plicatit-rn. alter a (r ariable ) short time. the population of the optimal requirement are vigorous hosts and are best e\em- phr-tophagt-rus target s-ill increase verv rapidly to exceed re- plified by the sterngrhvnchous homoptera: on the other markablv its former numbers. u'hat is termed in pest man-

2N :7 agement vernacular >. The result is further and cept the use of props when berries are formed. so as to repeated application of the pesticide at shorter and shorter prevent mechanical injury to the bunches. intervals. and the development of resistance by the repeated 2. Growing the vines (as cordons) on horizontallr'-stretched elimination of the weaker individuals in the treated popula- metallic wires in an east-west direction. tion. In mature orchards, the use of contact pesticides has 3. Growing'.he vines on ralsed trellises ca. two meters high. another added danger to the one mentioned; since it kills a The first method was very suitable for ploughing when ox proportionately higher number of predators and of the deli- ploughs were common,and isnow rapidly loosing ground due cate and highly susceptible, tiny parasites. to abandonment of ox ploughing. In this type of vineyards. With time, a mature orchard treated with proper, selective the only pest was the phylloxera, and to a very minor degree, pesticides, will form a stable ecosystem in which the trees, wasps and hornets. No fungus diseases were of any signifi- the phytophagous populations and those of their cance, because grapes were only grown in rain-fed areas natural enemies live together in more or less proportioned without supplementary irrigations. populations, termed . When the balance is disrupted due to unusual conditions or to faulty management The second method or cordon growing is the least condu- operations that favour a threatening increase of the phy- cive to pest or fungus attacks, due to the non suitable drying tophagous populations, resort to selective pesticides becom- action of the sun and wind on the said organisms. es necessar\'. The third method of grou'ing srapes is verv conducive to II. Pests of Citrus the spread of pests and diseases. due to the appreciable rise in underneath the- rines. and the prevention of sun- These can best be divided into. ( I ) pests of vegetative hurniditv organs, (2) pests of reproductive organs. and (3) r.ectors of Iight from reachine the soil or the . Unfortunatelr'. the ..fashionable ,, plant diseases. method has become and expensive for the gro\\'er and the consumer. \ou' that practicallr all vines are 1. Pests of vegetative organs often attack also the reproduc- grafted on American stalks. phvlloxera is no more a problem tive organs, but not vice versa. Among the most important in all vineyards. are the Homoptera, and the Acarina, many of which have However, in the vines grown on trellises. the following a cosmopolitan distribution. The commonest ones in the pests have to be controlled. The grape berry moth ., Lobesia and Middle East are: (a) Homoptera, including Near botrana, the mealybug, , and the fungi caus- Aonidiella aurantii, Lepidosaphes spp. , Saissetia oleae, ing powdery mildew, and downy mildew , Chloropsalta viri- Planococcus citri, Dialeurodes citri, Coccus hesperidum, dissima in North Syria. To control the insect, it is recom- Icerya purchasi, Aphis gossypii, Toxoptera aurantii, Di- mended to cut and burn the twigs where egg-laying scars aphorina citri. (b) , including Bryobia praetiosa, occur, before the eggs hatch in August. Panonychus citri, Phyllocoptruta oleivora. The grape berry moth is controlled by sprays of Bacillus thuringiensis starting about end to mid April. The spray 2.Pests reproductive organs. (a) Diptera, capita- of Ceratitis should be repeated after 20 - 25 days, and is safe since this Dacus (b) Lepidoptera, Prays citri, phyllocnis- ta, zonatus bacillus is very selective against lepidopterous larvae . Plano- tis gnidiella; Acari, citrella, Cryptoblabes sheldoni, coccus citri is controllable with lime-sulfur sprays in winter, Phy llocop truta oleiv ora. and systemic organo-phosphates when the insect is actively 3. Vectors of plant diseases. Homoptera, Aphis Sossy' feeding, i.e. when the insects excrete honey dew. As to the pii, Aphis craccivorA, Diaphorina citri. powdery and downy mildews a number of synthetic fungi- for the integrated pest The following are recommendation cides have replaced sulfur and copper salt sprays. management tn cttrus groves: IV. Pests of Stone Fruit Trees a. Against hard scales; winter oils, The woody organs of all stone fruits suffer from the attack b. Against soft scales; systemic poisons when insects are of boring grubs, particularlv u'hen the trees are not irrigated active; also lime-sulfur at dormant concentration, during the hot summer months, or are rendered weak by c. Against fruit flies pheromones and chemosterilants i other means. There is a general tendency by the fruit grow- when the fruit starts to mature (change color from ers to neslect or totally ignore the fruit-thinning operation, green to yellow). no matter hou'heavy fruit set is. This mistake results in small d. Against acarina; acaricides. lime-sulfur. s'henever the fruits. with a low sugar content, and a progressive weakness red spiders or are present. of the tree, year after year, thus exposing the roots and III. Pests of Grapes trunks to the attack of a number of borers. Irrigation, fruit- Grapes are generally grown in three different wa)'S on an thinnirrg, pruning, and proper nutrition are the most impor- extensive scale in the Middle East. The ways, or methods. tant management practices that guarantee a long, profitable have an influence on species that attack the vines, as well as lir"e of stone fruit trees. There is a number of pests of stone the level of injury they cause. The three methods in general fruit trees that are common to all species. These are the (1) use are: Coleoptera , Capnodis spp. ; Cerambyx dux.; and Scoly- 1. Prostrate growth on the ground all around the year, eX- tus spp. (2) Hymenoptera , Pterochloroides persicae, and

LrJl .)tJl qtil ili, -199 different -infesting aphids. fruits. This pest is controlled by one spray application of The pests that attack the fruits are to a great extent species- systemic crgano-phospate insecticide. which has to be ap- specific. (3) the Diptera, Ceratitis capitata is most serious plied right after petal fall. peach to and apricot fruits, and odinadiplosis amygdali on Eurytoma amygdali is also an univoltine species, whose almond buds . (4) the Hymenoptera arg represented by female introduces its ovipositor in very young almond fruits, Hoplocampa flava, and H. minuta on Japanese prunes, and and lay one egg on the young seed. When the egg hatches, Eurytoma amygdali on almonds. (5) the Coleoptera the larva starts feeding on the gelatinous seed at that time. are represented only by one fruit pest of apricots Rfty nchites Larval development is comparatively slow, so that when the auratus in Syria and the Baalbak-Hirmel area in Lebanon. larva reaches its full-growth, the rest of the seed would have Acari Acalitus (6) , phloeocoples on almond buds; tetrany- hardened in June. This pest is also very vulnerable to syste- chids on the of most or all stone fruits . (7) Homop- mic organophosphates, if applied to almond trees when the tera , Brachycaudus amygdalinus and B. helichrysi on the majority of the set fruits have reached the size of a dry leaves of almonds, and Hyalopterus pruni on the leaves of chickpea. plums, prunes and apricots. Rhynchites aurontus is also univoltine, but much more dif- Control of Ceratitis is best achieved by the use of attrac- ficult to control, due to extended time of appearance of tant baits to which a chemosterilant is added; the application adults in spring. The adult female bores with its mouth parts time starts when the colour of fruits begins to change from the surface of a young apricot or cherry fruit, and lay one egg green to yellow. Treatment has to be continued as long as the in the hole. When the egg hatches, the larva heads towards is fruit on the tree. the young seed, before the endocarp hardens, and feeds on The control of the almond bud midge , odinadiplosis is the very soft, gelatinous seed. Systemic organo-phosphates best achieved by planting late almond varieties, because such also kill this larva, however, two applications at one week's varieties escape attack by this pest. Early varieties subject to interval have to be applied; the first, a week after most petals attack by this midge should have the livd galls pruned and have fallen. burnt before mid-January. The use of systemic organo- Acalitus phloeocoptes in Lebanon and Syria does not rep- phosphates soon after the average length of leaves on the resent a problem any more, because it has killed practically trees reach five millimeters, help kill many neonete larvae. all susceptible almond varieties in its habitat. Here, too, one Hoplocampa flava and H. minuta are univoltine. They lay organo-phosphate application when very young leaves de- their eggs in the very young ovaries of plum and prune trees, velop on the almond tree will guarantee -free buds the and to a lesserextentin cherry flowers. When the eggs hatch, following spring. the larvae head towards the newly formed seeds and devour Aphid species that attack the stone fruit leaves rarely re- them. In the course of their development after devouring the quire any treatment, because of the large number of natural seeds in one fruit, the larva leaves the attacked fruit and enemies that prey on them. In case they are not reduced by attacks a second one. For its complete development of the their enemies carbamate aphicides or systemic insecticides larval stage of Hoplocampa will need to infest four or five are the best weapons against them. d.ilJl r,-Jl#t-rJ+ty'l JJJI €bFt:.rlri-rlJlr rrrfie.Jl ttn;l,rrat;:Jl;rtall .rulll ,r,ll.rru.r.:.Jt.r*tdy.Ji; .reE - 200 :z \y'l.rLy't {.tie tt+, .Urt;l O, oia e*i .:l;"Jl -r".; -TS: i,,"ii e*.-rJl rLJl ll C"i' lU Jt J,^J J_r-rJl +," € rlx*ll -tLJl Jl ri1 . aiYl ilE ld L..ty" Jt J-rlU C.*,- W), LiU" .rl-lLJ e-a-a;x* i-r-,'ls Ul-r ,J^il Jt tji:[ qsUl sul .r)tSl ;;l:l L$- .rL"3Jr" od; ,-tJl Pi .ifLFJ t+J ,.-iJl Tsfs ,.rt-jlt Crrt*ry .}L.i^.rJl 6j-ei q*, oia . )),l,Jl j" JYill CJLiJ yvJ jl . ilr, Jf +)V JhJYI oi,o JL.-i References

1 Talhouk, A. S . 7963 . Aceria phloeocoptes (Nal. ). in Middle East countries, Verlag Paul Parey, (Eriophidae) ein schwerer Schaedling von \'landelbaeu- Hamburg & Berlin,248 pp. men im Libanon und in Svrien. Anz. Schaedinesk u. 3. Talhouk. A.S. 1976. Contributions to the knowledge of Pflschtz. 36: 729 - 732. almond pests in East Mediterranean countries. l Talhouk, A.S. 1969. Insects and mites injurous to crops I\t Z. f . ans. Ent. 80:325 - 334.