IPM Stratergies for Walnut

Walnut beneficial insects Parasitoids Larval parasitoids Pupal parasitoid Nymphal/larval and adult parasitoids Predator...

Walnut beneficial insects

1. Parasitoids
1. Larval parasitoids
2. Pupal parasitoid
3. Nymphal/larval and adult parasitoids
2. Predators
3. IPM for Walnut

Parasitoids

Larval parasitoids

Pupal parasitoid

Nymphal/larval and adult parasitoids

Predators

IPM for Walnut

To know the IPM practices for Walnut, click here.

Source: NIPHM; Directorate of Plant Protection, Quarantine & Storage

 

2.8   

 

27 ratings and 0

Walnut Insect Pests

1. Stem borer
2. Shot-hole borer
3. Gypsy moth
4. Leaf roller
5. Grey weevil
6. Codling moth
7. San Jose scale
8. IPM for Walnut

Stem borer

Sarta is found in mountains up to an altitude of 2000 m. The area of origin of the pest is thought to be Pakistan and Western India, from which it spread westwards to Afghanistan and Iran and northwards to the Central Asian countries of the former USSR where it was first found in 1911 (in Samarkand, UZ). The pest continues to increase its range in these countries.

Biology:

• Egg: Females lay 1–3 eggs in slit-like niches in the bark of trunks and large branches shortly after leaving the pupation cells and for about two months. Each female lays 240–270 eggs in its life span. The egg period is 9 –17 days.
• Grub: Newly hatched grubs are light-coloured and about 4 mm long. Each grub makes its own tunnel (even if there are several eggs at the same place) between the bark and the wood. Excreta are ejected through the entry hole. At the bottom of this gallery, the larva overwinters protected by a double plug made from borings. The next spring, grub continues to feed, making tunnels deep into the wood. At the end of July, they prepare pupation cells protected by double plugs made from borings. The grown up grub is covered with golden hairs, 60 –70 mm long, with black mandibles.
• Pupa: Pupation occurs in these cells. Pupal period is two weeks. The adults stay in the pupation cells to over winter and leave them only in the spring.
• Adult: The adult has an elongated dark grey-brown body, 28– 47 mm long, with elytra covered with short silvery hairs. Shiny silvery spots form two irregular bands crossing the elytra. The male is usually smaller than the female. The male has antennae 2.5 times as long as the body, whereas the female antennae are shorter than the body Adults usually leave their pupation cells in April or the beginning of May at an average daily temperature of 20 °C. They are generally active in the evening and night. During the daytime, they hide under the bark, in larval tunnels, in winter tunnels and in other refuges.

Damage symptoms:

• Grubs enter the wood and, at the end of the first season of development, make a long (about 25 cm) tunnel upward and then turns to form a downward gallery of 15 cm
• Large emergence holes in trunks and large branches
• Borings at the basis of infested trees
• The adult beetles are conspicuous and may be seen sitting on the trunks
• Branch and tree dieback indicated by wilting and drying of leaves

Natural enemies of stem borer

Predators: Lacewings, ladybird beetles, carabids, syrphids, anthcorid bugs, reduviid bugs, nabid bugs, capsid bugs, big-eyed bugs, earwig, spiders, ground beetle, pentatomid bugs, red ants, preying mantis, Oligota spp., Orius spp., mirid bug, robber fly, black drongo, common mynah etc

Shot-hole borer

Biology:

• Egg: Bark dissections showed that eggs were deposited in small individual chambers on both sides of the mother gallery at regular distances throughout its length. On an average 52 eggs were laid per female, approximately 26 on each side of the mother gallery. The egg is slightly oval, shining, pale white and minute about 0.64 mm in length and 0.48 mm in width. The eggs in the egg niches were covered by the boring dust. The eggs hatched after an incubation period of 5-7 days.
• Grub: The grub on hatching was a minute white dot almost motionless, measuring 0.75 mm in length and 0.45 mm in width. As soon as the feeding started the larva became curved, legless grub and light creamy in colour. A full grown larva was 5.77 mm long and 1.89 mm wide. The head capsule measurements revealed that the larva passed through 5 instars before changing into pupa. The larval phase extended for 38-50 days.
• Pupa: The pupation took place at the ends of the larval galleries in pupal cells. The pupa was soft, white, averaging 4.05 mm in length and 1.60 mm in width. The pupal stage lasted for 6-18 days.
• Adult: The adult emerged from the pupal chamber by tunnelling straight through the bark over it. After emergence, adults flew to the crown of other suitable trees to produce the next generation. The cylindrical adult averages 4.00 mm long and 1.68 mm wide. It has shining black pronotum and dark red brown elytra with declivous abdomen. The adults lived for 45-60 days.

Life cycle

Damage symptoms:

• Grub tunnels in the sapwood on the trunk or branches
• Grub bore into the sap wood and making irregular tunnels.
• Feeding the vascular tissues
• interruption of nutrient and water transport on the tissue
• Drying of terminal shoot in early stage
• Frass comes out from several points and sometimes sap oozes out of the holes
• Wilting of branches or entire tree
• The bark of infested twigs, branches and trunks is perforated with many small round holes. In stone fruits, gum often will appear in and around these holes.
• Pin-hole borer damage usually is limited to weak, declining trees, and infestations frequently hasten tree or limb death

Gypsy moth

Biology:

• Egg: The egg mass is approximately 1.5 inches long and 0.75 inches wide. Eggs are attached to trees, houses, or any outdoor objects. The eggs hatch in spring (April) into caterpillars. Incubation period 5 to 24 days
• Larva: They have five pairs of blue dots followed by six pairs of red dots lining the back. In addition, they are dark colored and covered with hairs. Young caterpillars primarily feed during the day whereas the older caterpillars feed at night. When present in large numbers, the older caterpillars feed day and night. Older caterpillars are approximately 1.5 to 2.0 inches long. Larval period 66-100 days.
• Pupa: In early summer, Gypsy moth caterpillars enter a pupal or transitional stage. The pupae are dark brown, shell-like cases approximately two inches long and covered with hairs. They are primarily located in sheltered areas such as tree bark crevices or leaf litter. Pupal period ranged from 12 to 15 days.
• Adult: Adult Gypsy moths emerge from the pupae in 10 to 15 days. Females have white to cream-colored wings, a tan body, and a two-inch wingspan. Female Gypsy moths cannot fly. Females lay between500 to 1,000 eggs in sheltered areas such as underneath the bark of trees. Both the adult female and male can be identified by the inverted V-shape that points to a dot on the wings. Male and female moths lived for a period of about 3.5 to 6.0 days and 7.0 to 9.0 days. Gypsy moth has only one generation per year.

Life Cycle:

Damage symptoms:

• Caterpillars are gregarious but voracious feeder.
• They eat voraciously on leaves at night time.
• Under heavy infestation entire leaf is eaten sparing only hard vein.
• Defoliation of host completely results in failure of fruit formation.

Natural enemies of gypsy moth:

• Parasitoids: Exorista sp, Drina sp, Apanteles sp, Saracophages sp, Poilania sp, Anilastus sp, Anithomyia sp, Euplectrus sp, Brachymeria sp, Monodontomerus sp, Hyposoter sp, Pimpla sp etc.
• Predators: Lacewings, ladybird beetles, carabids, syrphids, anthcorid bugs, mirid bugs, reduviid bugs, nabid bugs, capsid bugs, spiders, red ants etc

Leaf roller

Biology:

• Egg: Eggs are laid in masses on the twigs of the host and covered by the female with a substance that hardens to create a smooth, hard surface. Larva: First instar larvae bore into the buds of their host plant. Later instars roll or tie leaves together or tie them to fruit. They feed on the leaves, flowers, buds or fruits of the host plant. Later instars roll or tie leaves together or to fruit and partially emerge from the shelter to feed.
• Pupa: Pupation occurs within the larval shelter and adults enclose in 10-12 days. Adult: The adult flight period lasts approximately 3 weeks. The length of the forewings is 6- 10.2 mm for males and 8.5-11.7 mm for females. Adults have a variable forewing colour consisting of combination of reddish brown, dark brown and tan. This species completes a single generation per year

Life Cycle:

Damage symptoms:

• Buds - Small entry holes in buds, chewed petals and flower parts.
• Blossoms - Petals webbed together, often remaining attached through petal-fall; inner flower parts eaten.
• Leaves - Chewed, rolled and tied together with silk.
• Fruit - Deep irregular holes in small fruit resulting in large russeted scars in mature fruit.

Natural enemies of leaf roller:

Predators:, Lacewings, ladybird beetles, carabids, syrphids, anthcorid bugs, mirid bugs, reduviid bugs, nabid bugs, capsid bugs, spiders, red ants etc

Grey weevil

Biology:

• Egg: Female Myllocerus spp. may lay up to 360 eggs over a 24-day period, and larvae emerge in 3-5 days. Eggs are laid directly on organic material at the soil surface. Eggs are less than 0.5 mm, ovoid and usually laid in clusters of 3-5. The eggs are white or cream-colored at first, then gradually turn brown when they are close to hatching.
• Grub: The grub range in size from 1.09 ± 0.05 mm as first instar grub to 4.0 ± 0.05 mm as ourth instar grub and are beige-white with a reddish brown head. They burrow into the soil where they feed on plant roots for approximately one to two months.
• Pupa: The grub pupates in the soil for approximately one week.
• Adult: Adult weevils vary in length from approximately 6.0 to 8.5 mm; the female weevil is slightly larger than the male by 1.0 to 2.0 mm.

Life Cycle:

Damage symptoms:

• When adult weevils feed on leaves, they feed inward from the leaf margins (or edges), causing the typical leaf notching.
• There are some instances where the leaf material is almost completely defoliated, where the weevil has fed along the leaf veins.
• The adults prefer new plant growth.
• Intense feeding by numerous weevils may cause plant decline or stunting.
• Young seedlings may not survive a large amount of feeding damage.
• With healthy plants, however, the feeding damage may be considered cosmetic if the plant recovers.

Codling moth

The rate of development will vary with temperature, proceeding more rapidly in warmer weather and climates. Depending on the climate, codling moth can have two, three, and sometimes four generations per year.

Biology:

• Egg: Eggs are deposited singly on apples and leaves. Each egg is about the size of a pin head and is translucent, gradually darkening as the egg nears hatching. Eggs hatch in six to 14 days, depending on temperature. Within 24 hours of hatching the larvae burrow into the fruit. The first instar larvae have a pink body with a black head and are approximately 1/10 inch in length. The number of eggs laid per female ranges from 30 to 70.
• Larva: After the eggs hatch, young larvae seek out and bore into fruit or developing nuts. Codling moth overwinters as full-grown larvae within thick, silken cocoons under loose scales of bark and in soil or debris around the base of the tree. Larvae are cannibalistic. Full grown larva pinkish or creamy white with brown head and pupates in the soil litter.
• Pupa: After completing development they leave the fruit and drop from the trees to search out pupation sites and continue the life cycle in the soil or on debris under the tree; some crawl back up the tree to pupate in bark crevices. The larvae pupate inside their cocoons in early spring and emerge as adult moths mid-March to early April. The moths are active only a few hours before and after sunset, and they mate when sunset temperatures exceed 62°F.
• Adult: Adults are about 1/2 to 3/4 inch long with mottled gray wings that they hold tent like over their bodies. Their appearance blends well with most tree bark, making them difficult to detect. If you are trapping the adults, you can distinguish codling moth from other moths by the dark, coppery brown band at the tip of their wings. Adult forewings are dark grayish with waxy lines with a copper colored eye like circle toward margin.

Life Cycle:

Damage symptoms:

• It is a direct pest and hence causes severe damage to the fruit.
• Neonate larva enters the fruit through calyx and feeds on seed.
• Infested fruits lose their shape and fall prematurely.
• 30 to 70 per cent apple fruits are rendered unmarketable.

Natural enemies of coding moth

• Parasitoid: Trichogramma spp.
• Predators: Parus major, Passer domesticus

San Jose scale

Pest of 700 different species of fruits, shrubs and ornamental plants. Pest is active from March to December. Passes winter black cap stage in tree bark.

Biology:

• Nymph: Female San Jose scales give birth to living young that emerge from under the edge of the scale covering. Each female gives birth to 200-400 nymphs. These tiny yellow crawlers wander in a random fashion until they find a suitable place to settle. Immediately upon settling, the crawlers insert their mouthparts into the host plant and begin feeding and secreting a white waxy material (white cap stage); eventually the waxy covering turns black and is known as the black cap stage. Later the covers turn various shades from gray to black.
• Adult: Immature male and female scales are indistinguishable until the first molt. At this time, the male scale covering begins to elongate, while the females remain circular. Males molt a total of four times. Following the final molt, adult male scales emerge from the scale covering as tiny, yellow winged insects. They mate with the females who remain under the scale covering. Female insect body covered with grey scales. Yellow lemon coloured female is visible when covering is lifted. Female scales are very prolific and over a 6-week period can produce approximately 400 young. San Jose scale produce living young called crawlers; most other scales produce eggs. Crawlers move around for a short period in search of a suitable place to settle. It takes 25 days for males to mature and 31 days for females Five to six generations in a year.

Life Cycle:

Damage symptoms:

• Nymph and female scales attack all above ground parts.
• Feeding site turns into a characteristic purplish red colour.
• Initially growth of plant is checked but as scale increases in number plant may die.
• Fruits will have distinct “measles” spots on the surface.

Natural enemies of San Jose scale

• Parasitoids: Encarsia sp, Aphytis sp
• Predators: Ladybird beetle

IPM for Walnut

To know the IPM practices for Walnut, click here.

Source: NIPHM, Directorate of Plant Protection, Quarantine & Storage

 

2.76   

 

22 ratings and

Walnut Pests

1. Pests of National Significance
2. Weeds
3. Pests of Regional Significance
4. IPM for Walnut

Pests of National Significance

Insect pests

• Stem borer: Aeolesthes sarta Solsky (Coleoptera: Cerambycidae)
• Bark beetle/Shot-hole borer: Scolytus nitidus Schedl (Coleoptera: Scolytidae)
• Gypsy moth: Lymantria obfuscata Walker (Lepidoptera: Lymantriidae)
• Leaf roller: Archips argyrospilus (Walker) (Lepidoptera: Tortricidae)
• Mealybug: Drosicha dalbergiae (Stebbing) (Hemiptera: Margarodidae)
• Grey weevil: Myllocerus sp. (Coleoptera: Curculionidae)
• Walnut weevil: Alcides porrectirostris Marshall (Coleoptera: Curculionidae)

Diseases

• Leaf spot: Alternaria sp
• Leaf blotch: Marsonina juglanse (Lib.) Magnus and Gnomonia leptostyla (Fr.) Ces. & De Not.
• Dieback: Glomerella cingulata (Stoneman) Spauld. & H. Schrenk
• Powdery mildew: Phyllactinia spp.
• Walnut blight: Xanthomonas campestris (Pammel 1895) Dowson
• Anthracnose: Gnomonia leptostyla (Fr.) Ces. & De Not.,
• Phytophthora root and crown rot: Phytophthora spp
• Armillaria root rot (Oak root fungus): Armillaria mellea (Vahl) P.Kumm.
• Crown gall: Agrobacterium tumefaciens Smith & Townsend,
• Walnut canker: Geosmithia morbida M.Kolařík, E.Freeland, C.Utley & Tisserat

Weeds

Broadleaf

• Tropical spiderwort: Commelina benghalensis L. (Commelinaceae)
• Creeping wood sorrel: Oxalis corniculata L. (Oxalidaceae)
• Goat weed: Ageratum conyzoides L. (Asteraceae)
• Sowthistles: Sonchus spp. (Asteraceae)
• Congress grass: Parthenium hysterophorus L. (Asteraceae)
• Lambs quarter: Chenopodium album L. (Chenopodiaceae)
• Sweet yellow clover: Melilotus indica (L.) All. (Fabaceae)
• Toothed Dock: Rumex dentatus L. (Polygonaceae) Grasses
• Bermuda grass: Cynodon dactylon (Poaceae)
• Cogon grass: Imperata cylindrica (L.) Raeusch. (Poaceae)
• Blanket grass: Axonopus compressus (Sw.) Beauv. (Poaceae)
• Large crabgrass: Digitaria sanguinalis L. (Scop.) (Poaceae)
• Knot grass: Paspalum distichum L. (Poaceae) Sedges
• Purple nutsedge: Cyperus rotundus L. (Cypraceae)

Pests of Regional Significance

Insect pests

• Aphids: Chromaphis juglandicola (Kaltenbach) & Panaphis juglandis (Goeze) (Hemiptera: Aphididae)
• Coding moth: Cydia pomonella Linnaeus (Lepidoptera: Lasiocampidae)
• San Jose scale: Quadraspidiotus perniciosus (Comstock) (Hemiptera: Diaspididae)

IPM for Walnut

To know the IPM practices for Walnut, click here.

Source: NIPHM; Directorate of Plant Protection, Quarantine & Storage

 

3   

 

21 ratings and

Walnut Stage wise IPM

1. Pre planting
2. Planting
3. Vegetative stage:
4. Reproductive stage

Management	Activity
Pre planting
	Common cultural practices: Destroy the alternate host plants Sow the ecological engineering plants Sow sorghum/maize/ pearl millet in 4 rows all around the main crop as guard/barrier crop Plough the field before planting to destroy existing weeds in the field. Apply manures and fertilizers as per soil test recommendations. Grow the attractant, repellent, and trap crops around the field bunds. Proper selection of cultivars having commercial value and suitable for effective cross pollination Before planting of walnut trees, the proper soil selection be made, and the most suitable soil is loam with abundant organic matter. Irrigate the plants I - 2 fortnights before expected harvesting. To avoid wilting due to long dry spell of summer irrigate the plants. Orchard management practices be followed strictly like clean cultivation. Arrangement of efficient pruning tools be made before undertaking pruning job. If the plants / trees exhibit the deficiency of micronutrients, especially of boron go for the application of the same on the basis of soil and leaf analysis. 2 or 3 varieties of walnut are required to be planted for adequate pollination. Apply balanced dose of chemical fertilizers and FYM to up keep the vigour of the plant and to reduce the attack of shot hole, back beetles and other pest. Growing of flowering plants, especially Marigold and Maize on peripheries and legumes as inter cropping help in conservation of both predators and parasitoids and helps in nematode management.
Nutrients	Nutrient should be applied on the basis of soil test report and recommendation for the particular agro-climatic zone. Prepare land by ploughing and harrowing. The pits are dug in summer about a fortnight before planting and left undisturbed. Pits of about 1m x 1m x 1m size are dug at a distance of 10 meter in square system of planting.
Water management	Proper drainage as crop is water sensitive
Weeds	Plough the field before planting to destroy existing weeds in the field.
Planting
	Common cultural practices: Collect and destroy plant parts infested with insect pest and diseases Use weed free, healthy suckers for planting. Remove and destroy crop residues. Avoid planting during wet weather condition Take up planting in shade free area Avoid planting of pest infested saplings. Common mechanical practices: Prune and destroy the scale, borer and canker infested twigs / branches. Clip of diseased/ mildewed shoots. Remove and destroy dead and drying trees from the orchards Collection and destruction of egg masses of hairy caterpillar. Collect and destroy the fallen walnut weevil infested fruits. Whenever infestation of mealy bug is noticed, slippery bands of alkathane sheets above the ground be applied during April. Collection and destruction of fallen foliage in autumn. Burlap skirts around the tree trunks infested with hairy caterpillar for collection and destruction of larvae I pupae of the pest from May to end of June. Cover the exposed part of the stem to sun with dry grass or gunny bugs soaked with methyl parathion (0.1%) once a month from March to October for Controlling borer infestation. Complete collection, destruction of foliage and pruned wood in the orchards after leaf fall. Fallen fruits be collected and destroyed at every 10 days interval on the community basis
Nutrients	Planting is done in pits already filled with top soil and farm yard manure in 2:1 ratio. Add mycorrhiza culture @ 50 g/pit or a basket of soil taken from old walnut orchard to ensure mycorrhiza association with walnut roots.
Weeds	Use weed free seedlings for planting. Remove weeds from the pits before planting. Grow the recommended cover crops between the rows of walnut trees with recommended agronomic practices.
Pests, soil borne pathogens and other diseases	Cultural control: Care should be taken that water should not stagnate near the root zone
Powdery mildew	Cultural control: Use healthy infestation-free plants. Aphids usually spread through infested stocks, avoid planting infested stocks
Aphids	Cultural control Use resistant root-stocks belonging to Malling Merton series. Ecological engineering with buckwheat attracts parasitoid, Aphelinus mali
Vegetative stage:
	Common cultural practices: Collect and destroy crop debris Collect and destroy disease infected and insect damaged plant parts Provide irrigation at critical stages of the crop Enhance parasitic activity by avoiding chemical spray, when 1-2 larval parasitoids are observed Remove weed plants Common mechanical practices: Handpick the older larvae during early stages Collect and destroy plant parts infested with insect pest and diseases Handpick the gregarious caterpillars and the cocoons which are found on stem and destroy them in kerosene mixed water. Use yellow sticky traps @ 4-5 trap/acre Use light trap @ 1/acre and operate between 6 pm and 10 pm Install pheromone traps @ 4-5/acre for monitoring adult moths activity (replace the lures with fresh lures after every 2-3 weeks) Erecting of bird perches @ 20/acre for encouraging predatory birds such as King crow, common mynah etc. Set up bonfire during evening hours at 7-8 pm Common biological practices: Conserve natural enemies through ecological engineering Augmentative release of natural enemies
Nutrients	For achieving higher yields of quality product, generally nutrients may be applied according to the age of plant as mentioned below; Age of tree (years) Nutrient (grams per tree) N P2O5 K2O 1-3 10-20 30-40 20-30 4-6 30-60 40 40-80 7-11 100-250 40-60 100-250 11-14 250-750 75-200 750-1300 15th year and above 1800 500 1500 Apply manures @ 50kg per plant in Dec-Jan every year along with full dose of P and K. Nitrogen is applied in 2 splits, first half at 2-3 weeks before flowering and the remaining half a month later. The fertilizers should be applied in 20-30 cm deep and 30cms wide trench along the drip line of the tree
Weeds	Deep hoeing is recommended during the first year to check weed growth. Weeding should be done on regular basis especially around the plants. To suppress the weeds between rows, leguminous crops and vegetables can be grown as intercrops in the initial years. Use straw or plastic mulches to check the weed growth. Use slashing and mowing between the rows to control the weeds
Stem borer	Follow common cultural, mechanical and biological practices Cultural control: Keep the orchard healthy following good agricultural practices. Kill the stem borer larvae by inserting a flexible wire inside the hole and plug the hole with the cotton wick soaked in petrol and seal it with mud. Mechanical control: Prune and burn all attacked shoot and branches during winter.
Shot-hole borer	Follow common cultural, mechanical and biological practices Cultural control: Attacked shoots should be clipped off and destroyed. Clean hole and pour kerosene/petrol/crude oil or formalin into the stem borer hole and subsequently close entrance of the tunnel by plugging with cotton wool and paste the mud. Use light trap@1/acre
Leaf roller	Follow common cultural, mechanical and biological practices
	Follow common cultural, mechanical and biological practices Cultural control: Remove weeds and grasses by ploughing during June-July. Plough orchards during summer to expose the eggs to natural enemies and extreme heat. Flooding of orchard with water in the month of October kill the eggs. Raking of soil under the tree trunks and mixing with some soil dust in the early part of November for control of early instar mealy bug Soil solarization with thin polythene sheet for 30-40 days during hot summer Fastening of alkathene sheet (400 gauge)/grease band of 25 cm wide afterwards mud plastering of trunk at 30 cm above the ground in the middle of December. In July –August destruction of infested fallen leaves with scales Biological control: Raking of soil around tree trunk to expose the eggs to natural enemies and sun, removal of weeds and releasing 10-15 grubs Releasing 10-15 grubs of cocinellid predator, C. montrouzieri per tree.
Grey weevil	Follow common cultural, mechanical and biological practices Cultural control: Collection and destruction of infested and fallen fruits at weekly interval till fruit harvest. Ploughing of orchard after harvest to expose hibernating adults, reduce, infestation levels. Destroy all left over seeds in the orchard and also in the processing industries.
Walnut weevil	Follow common cultural, mechanical and biological practices
Leaf spot	Follow common cultural, mechanical and biological practices Mechanical control: Prune diseased leaves and malformed panicles harbouring the pathogen to reduce primary inoculum load.
San Jose scale, aphids	Follow common cultural, mechanical and biological practices Cultural control: Grow attractant flowers for natural enemies: viz., sunflower family, carrot family plants, buckwheat etc. Mechanical control: Pruning of infested branches and twigs Collection and destruction of pruned infested material. Biological control: Predators such as lady bird beetles - Chilochorus bijugus, Pharosemnus horni, Coccinella septumpunctata, Chlilochorus tristis, Adalia bipunctala, Synharmonia sp. Exochomus quadripustulatus, Hippodamia convergens @ 30-50 adults / infested tree. Green lacewings (Chyrsoperla sp.) and Syrphus sp. @10-20 1st instar larvae/tree. Parasitiods such as Encarcia perniciosi and Aphytis diaspidis @ 2000 / infested tree after 15 days of insecticidal sprays and 10 days after fungicidal sprays.
Downy leaf spot	Follow common cultural, mechanical and biological practices
Leaf blotch	Follow common cultural, mechanical and biological practices
Dieback	Follow common cultural, mechanical and biological practices
Powdery mildew	Follow common cultural, mechanical and biological practices Cultural control: Spraying at full bloom needs to be avoided. Mechanical control: Prune diseased leaves and malformed panicles harbouring the pathogen to reduce primary inoculum load
Walnut blight	Follow common cultural, mechanical and biological practices
Anthracnose	Cultural control: Removing leaf debris from around plants Avoiding wetting foliage when irrigating. Spacing trees adequately to increase air circulation and applications of nitrogen fertilizer in Spring to delay leaf maturity and reduce the development of lesions.
Phytophthora root and crown rot	Cultural control: Planting trees in well-draining soils Drainage can be improved by levelling soil or installing drainage systems Avoid wetting tree trunks when irrigating ensure graft union is several centimeters above the soil line when planting trees.
Armillaria root rot (Oak root fungus)	Cultural control: Diseased or dead plants should be uprooted and removed. Planting resistant rootstocks is the most effective method
Crown gall	Cultural control: Plant disease-free nursery stock. Plant trees in well-draining soils. avoid wounding the plants
Walnut canker	Follow common cultural, mechanical and biological practices
Reproductive stage
Nutrient	Nitrogen is applied in 2 parts, first half at 2 weeks before flowering and the remaining half in two splits at 3 weeks after fruit set and during early July. The band application of nitrogenous fertilizers should be preferred over broadcasting. Under rainfed conditions, apply N through 1 or 2 foliar sprays of urea (0.5%) after fruit set. Apply recommended micronutrients, if symptoms are observed. Fruits are deformed under boron deficiency. To avoid boron deficiency, apply H2BO3 (0.1%) as foliar spray.
Weed	Remove weeds around the plants/trees. Use straw or plastic Mulch to avoid weed growth and to maintain soil moisture for longer period. Mulching tree basins with 10-15 cm thick dry grass also checks weed growth. During the initial 2-4 years, pea, bean, soybean, and cowpea enrich the soil and give economic returns also.
Stem borer	Same as in vegetative stage
Codling moth	Follow common cultural, mechanical and biological practices Cultural control: Apart from aforesaid practices, regular monitoring is mandatory for moths, For codling moth: Use synthetic codling month for mating disruption at a height of 6-8 feet or Dispensers should be deployed within 1 meter of the top of the canopy prior to spring emergence during late May to 3rd week of July
San Jose scale, aphids	Same as in planting and vegetative stages
Downy leaf	Same as in vegetative stages
Spot, Leaf blotch, Dieback, Powdery mildew, Walnut blight, Anthracnose, Phytophthora root and crown rot,

Source: NIPHM, Directorate of Plant Protection, Quarantine & Storage

 

3.22   

 

40 ratings and 1 comments