Enemies and diseases the grower should know
Enemies and diseases the grower should know
Almond tree
Enemyi
1. Euryvolume (Eurytoma amygdali, Hymenoptera, Eurytomidae): This insect is the most important enemy of the almond tree. Due to its oviposition, premature fruit drop is caused, while the main damage results from the destruction of the edible part of the fruit by the insect larva. The insect then overwinters inside the affected almonds (they usually remain mummified on the tree). The new insects emerge from the fruits in mid-spring. The sensitivity of almonds to the attack by broadleaf beetle varies from variety to variety, and is also related to the annual climatic conditions.
Prevention: Removal and burning of the mummified fruits.
Treatment: Two-three sprayings of insecticides in the months of April-May, with guidance as to the time of their application by the responsible agronomist.
Asthenews
1. Eata pstartview/monilia (Monilinia laxa): For the tonsil, it seems to be a problem after the fourth or fifth year. The pathogen causes drying and necrosis of the flowers and from there it spreads to the twigs. The fungus survives in the affected parts of the plant (inflorescences and twigs) and in this way the attacks continue the following year. Attacks are favored by high relative humidity (spring rains), while susceptibility varies from variety to variety.
Prevention: Removal of affected twigs and branches before leaf fall. Treatment: Three sprays are recommended, with guidance as to the timing of their application by the responsible agronomist.
2. Polystiimpregnation (Polystigma fulvum plus. Polystigma ochraceum): This ascomycete attacks almond leaves in the spring. Symptoms of the infestation are orange spots on the leaves and the fungus survives on infected leaves in the soil. Attacks are favored by high relative humidity (spring rains) and susceptibility varies from variety to variety.
PrThetake: Removal of affected leaves from the field.
Optowpiss: Sprays from the development of the "eyes" until the beginning of June (depending on the weather conditions), with guidance as to the time of their application by the responsible agronomist.
3. Coryneo (Coryneum beijerinckii, Wilsonomyces carpophilus): This fungus causes necrosis in the buds, necrotic spots in flowers, leaves, shoots and young fruits. The development of the infestation creates ulcers on the shoots, while with the fall of the tissues of the spots, the pathognomonic symptom of "shrapnel holes" becomes visible. The fungus survives in the affected plant parts and infestations are favored by high relative humidity (spring rains).
Prevention – treatment: Sprays from leaf fall (repeat in winter) and in spring after petal fall, with guidance as to the exact time of their application by the responsible agronomist.
Walnut Enemies
1. Cydia pomonella: This lepidoptera is the main enemy of the walnut tree. It prefers warm lowland areas, with its larva (caterpillar) eating the edible part of the fruit. It has two-three generations/year (late spring, July, August), with the first being more destructive, since the larva attacks more than one walnut.
PrThetake – objectowpiss: Sprays based on the results of traps and agricultural warnings, with guidance as to the exact time of their application by the responsible agronomist.
2. Frisee (Chromaphis Juglandicola and Callaphis Juglandis): Aphids feed on the sap of the leaves, weakening the tree and reducing its production. The infestation is very characteristic thanks to the abundant honeydew secretions.
PrThetake – objectowpiss: Sprays based on assessment of the infestation by the responsible agronomist.
3. Sqafingernails (KiTrinos and MrTheangry): Cutworms cause significant leaf damage by feeding on the sap, resulting in leaf drop and severe tree weakening (reduced production).
PrThetake – objectowpiss: Sprays based on assessment of the infestation by the responsible agronomist.
4. Blastoryktis (Oberea linearis). Attacks by this insect have increased in recent years. A critical factor is its timely detection by the responsible agronomist, who will indicate the chemical interventions, but also the necessary cutting of the affected parts.
Illnesses
1. Bacteriaiosis (Xanthomonas arboricola pv. juglandis): First, it attacks the young vegetation, then the male and female flowers (the most sensitive part of the plant) and, finally, the walnut fruit. When conditions are favorable, this disease can cause a large reduction in production.
PrThetake – objectowpiss: A spray with copper at the beginning of vegetation and the rest according to the infestation and the conditions, under the guidance of the agronomist in charge.
2. Humanacosis (Gnomonia leptostyla): The fungus infects leaves (defoliation, tree weakening, production reduction) and survives on infected leaves in the soil.
Prevention – treatment: Sprays based on assessment of the infestation by the responsible agronomist.
Chestnut Enemies
1. Chestnut weevil (Curculio elephas): This beetle is a serious enemy of the chestnut tree. The damage is done by its larva, which feeds on the inside of the chestnut. Attacks are more important in early varieties than in late ones.
Prevention: Infestations are much more limited if the affected fruits are removed from the field.
Optowpiss: Sprays based on assessment of the infestation by the responsible agronomist.
2. KarpThechestnut capsulesas (Pammene fasciana / Laspeyresia splendana / Laspeyresia fagiglandana): The damage is caused by the larvae of lepidoptera (butterflies) that feed on the edible part of the fruit. In years of good fruiting, infestation can act as a natural way of fruit thinning and lead to large fruit production.
PrThetake: Infestations are much more limited if the affected fruits are removed from the field.
Optowpiss: Sprays based on assessment of the infestation by the responsible agronomist.
3. RefstartMrs. Chestnutas (Dryocosmus kuriphilus Yasumatsu): It is the most serious enemy of the chestnut tree, recently observed (2014) in our country. The wasp larva overwinters inside the buds and in the spring, after the buds open, spots are created on the young vegetation where the larvae feed. As the insect matures, the caterpillars dry out and become woody, remaining on the trees for up to two years. The formation of calluses arrests shoot growth and reduces fruiting by 50%-70%. Severe infestation can even lead to the death of the affected chestnut trees.
Optowpiss: Biological control using the parasitic insect Torymus sinensis is considered as a permanent and effective treatment of the insect.
Illnesses
1. Melaconnection (Phytophthora cambivora): It is a disease of the roots that is identified with the progressive drying of parts of the tree (leaves, shoots), hemiplegia or even apoplexy. Its typical symptom is the irregularly shaped necroses on the neck of the tree from which a dark liquid oozes. The infestation results in the weakening of the tree and eventually its drying.
PrThetake: Avoiding mechanical damage and wounds with tillers and tillers, avoiding flood and furrow irrigation, avoiding wetting the neck of the plant and using subjects resistant to inking.
Optowpiss: Exposing the affected parts to light and coating them with 10% copper sulfate paste. Ammonium nitrogen fertilization also helps, while chemicals can be used under the supervision of the agronomist in charge.
2. Elkos of Kastanias (Cryphonectria parasitica / Endothia parasitica): The fungus enters the plant through wounds and attacks the bark and its aerial part, causing ulcers on the branches. The leaves above the ulcer become chlorotic and then die and fall off. A typical symptom is the development of numerous glutinous growths under the ulcer.
Prevention: Disinfect pruning tools, cover wounds/incisions, avoid injuries. Treatment: Biological control, by inoculating the ulcers with sub-infectious strains of the fungus.
Peanut Enemies
1. Euryvolume (Eurytoma plotnikovi): The insect appears in large populations from late spring to mid-summer, with the ability to cause a large reduction in production. It overwinters in the affected fruits, which remained on the tree (it does not survive in fallen ones).
PrThetake – objectowpiss: Removal of affected fruits from the tree. Monitoring of weevil populations and level of infestation and spraying under the guidance of the agronomist in charge.
2. Psyetc (Agonoscena pistasiae, A. targionii, A. cisti and Megagononsena gallicola): These four species that have been identified in Greece have a different presence in each region of the country. So, the insults and their treatment differ in time from region to region. The main damage, which is the fall of the leaves and the destruction of the young buds, takes place during the summer. The flea prefers female trees.
PrThetake: Removal of all dry plant organs and incorporation of fallen leaves into the soil. Spreading the trunk and arms with Bordeaux paste in early spring. Perimeter planting of a few bushes to attract the flea's natural enemies.
Optowpiss: Sprays by area and based on the infestation under the guidance of the agronomist in charge.
3. Skowros (Tinea pistaciae): The larvae of this microlepidoptera burrow into stems and inflorescences. In the summer, fruiting of the young fruits is caused. It has five generations a year. In the summer we have about one generation every month, while the last one appears in the fall.
PrThetake: Destruction of related native trees, which exist near the arboretum (e.g. linden). Removal of affected fruits. Winter mulch before new growth starts.
Optowpiss: Sprays based on the infestation under the guidance of the agronomist in charge.
4. Schoolyher peanutas (Acrantus vestitus): This beetle attacks the trunk, arms and branches of the plant and is the most serious wood-eating insect of the pistachio. It opens galleries on young green shoots and destroys buds on woody shoots.
PrThetake: Keeping the tree healthy. Removal of dry twigs and laying of spawning traps (dry hanging twigs, which are burned in February).
Optowpiss: Sprays based on the infestation under the guidance of the agronomist in charge. Illnesses
1. Votryosfairia (tesmooth shapestart: Botryosphairia dothidea, incompletestarts formstart: Neofusicoccum vitifusiforme): The infection starts from ascospores and pycnidia, which are found on dry branches or in ulcers on pistachios (or other neighboring trees, e.g. olives). The infestation causes ulcers on the shoots, drying of leaves, buds and fruit. The disease is favored by very high temperature and humidity values.
PrThetake: Destruction of affected plant parts. Good pruning in March to ensure good ventilation and application, preferably, of drip irrigation. Keeping trees in good condition and avoiding water stress. Also, the soil should be free of weeds. Avoiding wounds and insect infestations.
Optowpiss: Sprays based on the infestation under the guidance of the agronomist in charge.
2. Septoriosis (tesmooth shapestart: Mycoshaerella pistachio, incompletestarts formstart: Septoria pistacinna): This disease affects the leaves, on which it creates dark spots. This results in premature defoliation and weakening of the tree. The disease is favored by high relative humidity.
Optowpiss: Sprays based on the infestation under the guidance of the agronomist in charge.
3. Scoreiace (Pileolaria terebinthi): The disease affects the leaves, inflorescences and fruiting bodies, causing characteristic deformations. It overwinters on the affected leaves on the ground.
PrThetake: Avoid planting the tree near forest areas due to the presence of a large number of related native plants (e.g.
Treatment: Sprays based on the infestation under the guidance of the agronomist in charge.
Hazel
Enemies
1. Acurry of the eyesown (Eriophyes avellanae and Phytoptus avellanae): These tiny mites overwinter inside the buds, which swell in late winter and early spring. Susceptibility varies from variety to variety.
PrThetake–objectowpiss: Monitoring of the insect with double-sided adhesive tapes and sprays based on the results and under the guidance of the agronomist in charge.
Illnesses
1. BacterialThecancerinos (Pseudomonas syringae pv. avellanae): The infestation leads to the wilting of the branches and the total drying of the tree.
Prevention – treatment: Supply of healthy propagating material. Monitoring the field in spring and summer and removing and burning affected shoots. Spraying under the guidance of the responsible agronomist.
