SARITA IS READY TO CARE WITH FARMERS
With two sunny and rainy seasons, Dak Lak has a climate and soil that is very suitable for growing durian trees, the main varieties are: Dona (Lai from Monthong of Thailand). Most of the farmers have spontaneous farming techniques, self-study experience, no common and scientific standards, and have not met VietGap standards. Irrigation - drainage system is natural, not strictly controlled, mainly based on natural elevation. Soil-water quality has not been measured and assessed. Wind speed, sun intensity, and temperature are not monitored according to standards. Along with that, the use of plant protection drugs is not according to the safety standards allowed by the state, the origin and quality are unknown. Fertilizers and the quality and origin of fertilizers have not been strictly controlled. The situation of fertilizing fake fertilizers and poor quality fertilizers still occurs. The above factors cause pollution of water sources and cultivated land in the long term, leading to unqualified products for export to difficult markets such as Japan, Europe, and the US.
Because of these concerns, SARITA with the slogan "Quality Pioneers" was determined to put theory into practice for farmers participating in the supply chain cooperation with the company.
The company is ready to send technical staff to the durian garden to train and support quality garden care techniques.
Each stage of development of durian trees will have different types of pests and planthoppers, so it is necessary to regularly check the garden for early detection and prevention.
I. Pests and pests of durian
1. Powdery mildew (Allocaridara malayensis) Also known as jumping planthopper, white planthopper.
Usually appears and thrives when the tree has young shoots. Larvae and adult larvae suck sap from young leaves and buds, causing small leaves, curling, poor growth of branches, and thinning of leaves.
Preventive measures:
+ Spray water with high pressure nozzle.
+ Use insecticides: Alternately use drugs with the following active ingredients: Imidacloprid, Abamectin, acetamiprid, profenofos, thiametoxam ... Concentrations as recommended by the manufacturer, pay attention to spray in the early morning or late afternoon.
. Green planthopper Amrasca sp
Green planthoppers suck sap on young leaves and young buds, making leaves small, twisted, heavy, which can cause leaf burn, mass defoliation, dry branches, and broom phenomenon on durian.
Green planthoppers sting, cause wounds, create conditions for fungi and bacteria to penetrate and cause diseases to plants. Strong resistance to drugs, it is necessary to alternately spray many different drugs, use and prevent simultaneously for the whole garden, which costs a lot of money and money. Currently, people often pay attention to increasing the dosage when mixing sprays, resulting in increased costs and increased resistance of green planthoppers.
Preventive measures:
* Regularly check and visit the garden to detect and handle in time.
* Control plants to focus on young shoots for easy prevention.
* Create conditions for the garden to open.
* Alternating spraying of drugs containing active ingredients thiamethoxam, profenofos, acetamiprid, imidacloprid, Beta-cyfluthrin, Abamectin, Spirotertramat, Buprpzein... every time the tree has young buds.
. Thrips that damage durian (Scirtothrips dorsalis and Thrips sp)
Adults: Very small in size, about 0.8-1mm long, brown in color, long head antennae, occupying 1/3 of the body, two narrow wings, front wings in the middle part. When mature, they lay eggs scattered in leaf tissue.
Symptoms of thrips damage to Thai durian trees
Eggs: The size is quite small, the new laying is milky white, when it is close to hatching, it is pale yellow.
Larva: Body similar to an adult but without wings, yellow-orange, with many small hairs on the body.
During the day, thrips are relatively active. When shaken, they avoid moving to another leaf or fall to the ground pretending to be dead. They often hide in young leaves because they do not like direct light. When it is cool, they will crawl out. As larvae they are also very harmful. On durian trees, they damage young leaves and flowers. Thrips usually thrive in warm, hot, and dry conditions.
On leaves: They often sting to slow leaf growth. Severely damaged leaves may be curled.
On flowers: They suck the sap, making the petals black. The pistil has melted plastic. If the damage is severe, it will cause the flowers to fall off. Thrips also create conditions for the soot fungus to grow and blacken the leaves.
Preventive measures:
Maintain humidity in the dry season above 65% with green grass, apply a lot of organic fertilizer. Using a strong hose to water the plants or applying sprinkler irrigation techniques on the foliage in the dry season also limits the number of thrips in the garden.
Prune off severely damaged parts and destroy them. Regularly prune branches to limit hiding places for thrips.
Thrips are very resistant to drugs, so alternately sprayed with drugs such as: Spinetoram (Radiant 60SC ...), Clothianidin, Beta-cyfluthrin, Acetamiprid,
Imidacloprid (Confidor 100SL, ...), Carbosulfan (Marshal 200SC, ...), Abamectin sprayed at the time of young shoots and flowering.
Note: Thrips do not like light, when it is shady they will crawl out, so spray in the afternoon.
4. Leafy Beetles
Beetles are harmful almost all year round, in which the heaviest is in the dry season months. Types of beetles that damage durian: beetles (green, brown, black), hair clippers... Most beetles belong to the family of chewing mouths, they eat the flesh of young leaves, bite off young buds or cut off the tops. The growth of durian trees makes the tree exhausted, the lack of leaf area leads to poor photosynthesis, stunted plants, even tree death if not detected and treated in time.
Beetles often appear in the evening and at night, they fly in groups. During the day they hide in dense trees or underground, so they are rarely detected. When the branches vibrate, the beetles will fall to the ground and lie motionless. The beetle's bite creates a wound, allowing fungi and disease-causing bacteria to easily penetrate the tree.
Preventive measures:
Clean the garden for ventilation, reasonable irrigation, avoiding the dry garden, creating conditions for beetles to arise, develop and cause harm.
Care, regularly check plants for early detection and prevention. When detecting spraying with active ingredients fenitrothion + Fenpropathrin, Cypermethrin, chlothianidin, Cyhalothrin...
5. Green caterpillars eat leaves:
Young caterpillars often live on the buds and undersides of young leaves, using silk to wrap the young shoots and eat inside, at high density the caterpillars eat the leaves, leaving only the veins. Pests cause damage from young plants to adulthood.
+ Prevention measures: Monitor trees for early detection and timely prevention. Catch and kill larvae and pupae when the population is small and concentrated on young shoots. If it is necessary to spray one of the chemical drugs with active ingredients such as: Abamectin, diafenthiuron, permethrin...
6. Planococcus fruit mealybugs
- Planococcus sp. Attack on the fruit, suck the juice of the peel. In addition, their secretions cause soot fungus to grow, making the pods black.
Aphids cause damage during fruit development from infancy to maturity. They suck on the fruit stalks and on the fruit, they are often concentrated in clusters of fruits.
On young fruit, if the density of mealybugs is high, the fruit will not develop and may fall prematurely. if mealybug density is low or attack when the fruit is large, the fruit will continue to develop but the quality of the fruit will be reduced.
- During life, aphids secrete sweet nectar, creating a suitable environment for soot fungus (Capnodiun sp) to develop, causing the fruit to be covered with a layer of soot, dirty black, reducing fruit design. Mealybugs live in symbiosis with ants. by ants carrying aphids from place to place, from tree to tree when the place where the mealybugs are feeding has run out of sap. On the contrary, the secretions of aphids contain a lot of bile as food for ants.
In addition, the places where mealybugs suck will create wounds for other fungi to enter, causing fruit rot later on.
Preventive measures:
Spraying water directly on the fruit can wash away the mealybugs on the fruit.
Prune out severely infected young fruit.
Avoid intercropping with plants infected with mealybugs such as custard apple, rambutan, etc.
Spraying when the density of mealybugs is high with drugs containing active ingredients such as: spirotetramat, buprofezin, Clothianidin…….
7. Stem borer (plocaederus ruicoruis)
The stem borer belongs to the family Cerambycidae, the order Coleoptera, the adult hair clipper usually has a brown body, the body size is usually 25 - 30 mm long, on the body is covered with a gray, clear hair. growth stage
Once mature, the stem borer is usually no longer able to harm durian trees.
Young caterpillars have a body length of 30 - 45 mm, the body is milky white.
The adults often lay eggs in the crevices of the trunk, cracks or branches, so when the eggs hatch, the larvae can follow these lines to attack the trunk or branches and bite the upper part of the trunk. , branches of the tree can die if not detected in time and treated. After growing, the larvae will come out of the tree to make cocoons.
When a tree is attacked by stem borers, they move deep inside, biting everywhere, forming small tunnels inside the trunk that are not oriented. No matter where they bite, they excrete through the holes they bite, so detecting them is not easy. When detecting trees with strange symptoms such as wilting or retarded growth, it is likely that the tree has borer and it is better to carefully check those trees for timely treatment.
The caterpillar eats the soft shell between the stem and the hard outer shell, so when the worm causes two more or eats around the stem e makes the plant unable to move water and nutrients
Preventive measures:
The stem borer usually hides in the trunk of the tree, so when the larvae get inside, it is often difficult to destroy the root of this pest. To prevent and treat pests promptly, we can apply effective control measures below:
* Should regularly visit the garden to detect early branches or tree trunks attacked by borers. You can use wire or sharp knives to look for holes by hand.
* Conduct sawing to remove heavily borer branches and take them out of the garden to destroy.* Use active ingredients: Alpha - Cypermethrin (Cypermethrin) + Profenofos, then take a syringe to pump into the highest hole or use cotton to dip it in. medicine and then attach it to the end of the wire and insert it into the hole. Next, use clay to seal the hole to kill the worms in the trunk.
8. Branch borer
Five species of weevils attack durian trees: Xyleborus similis, Xyleborus fornicatus, Xyleborinus sp., Sinoxylon anale and Platypus parallelus. In which, two species of X. similis and X. fornicatus cause common damage on durian stems and branches; Two species of S. anale and P. parallelus have been reported to attack only the dead wood of durian trees.
The species Xyleborus similis attacks the base, trunk and main branches, forming an intricate network of chisels between the wood adjacent to the bark; species Xyleborus fornicatus attack branches, twigs, damaged or weakened branches, they cut straight from the bark into the wood, then the chisel branched.
Weevils damage mainly in the dry season and decrease rapidly in the rainy season, the damage to trees on the trunk is very closely correlated with pus disease - root rot. If the disease is severe, the weevils will penetrate the core, cutting off the flow of water and nutrients up, so from the position of the weevils upwards, the branches will dry out and die.
Preventive measures:
* Check the garden regularly to detect weevils early, collect and destroy severely attacked branches.
* Because the hole is small, you can use cotton wool soaked in drugs with active ingredients such as: Cypermethrin, acetamiprid, buprofezin ... inserted or swept into the hole.
* Note: In the process of spraying insecticides, spraying on the leaves, stems and branches will limit weevils. Check if the borer has oozed pus, then it is necessary to prevent and treat the harmful pus disease on durian trees.
9. Red Spider
Durian red spiders are usually very small (about 0.3 - 0.35 mm), orange or dark red, with many stiff hairs on the body. Newly hatched larvae are yellow, light brown, difficult to see with the naked eye.
Red spider mites are highly reproductive, causing damage by feeding on leaf cuticles. Red spider mites damage mainly on old leaves and near old leaves, live and suck on 2 leaf surfaces (more on the lower side). When severely damaged, the young leaves are often small and twisted, the veins are raised, the suckers leave tiny dots, the leaves are yellow and silver and fall off. At the stage of red spider business, the fruit skin is rough, the skin color is bad, the fruit is slow to grow, the tree is stunted, and underdeveloped.
A female spider can lay 20-50 eggs within 2-3 days. Eggs are laid scattered on both sides of leaves or on the fruit.
The hotter the weather or the drier the weather, the shorter the life cycle of the red spider, causing the spider population to increase rapidly and cause more damage.
Preventive measures:
* Check leaves regularly to detect harmful spiders early.
* Prune branches to create a ventilated garden, do not plant thickly.
* Balanced fertilizer application, concentrated fertilizer for young shoots to come out at the same time.
* In the dry season, you should regularly water the foliage to keep the humidity high
* High number of harmful spiders can spray insecticides such as Abamectin and mineral oil or pyridaben, sulfur, fenpropathrin, spirodiclofen...
spray 02 times, separated by a capacitor/time.
II. Disease prevention
2.1 Leaf blight (Rhizoctonia sp.)
Lesions on leaves are initially dark, succulent and irregularly shaped patchy spots, then spread like boiling water burns. When old leaves turn brown, dry leaves fall, dead branches die. The disease appears at the tip of the leaf, between the leaves or the entire surface of the leaf, causing leafless, dead branches.
Preventive Measures:
* Prune branches close to the ground, creating a canopy for the garden to open.
* Collect and destroy infected and fallen leaves.
* Use drugs Anvil 5SC, Validacin, Monceren 250SC... to prevent.
2.2 Anthracnose (Colletotrichum gloeoporioides)
The disease appeared and quickly spread heavily on seedlings and nurseries, especially at the beginning of the rainy season and on frosty days. The disease usually appears on mature leaves in the area from the center of the canopy down to the ground. On leaves, the disease usually starts from the leaf edge or leaf tip and spreads inward, nearly round or indeterminate. The inner red-brown lesion has dark brown wavy borders that are almost concentric. Older lesions are pale brown in color, on which the fungus forms a black needle-like fovea. Severe disease causes dry leaves to burn and fall prematurely, causing bare branches to die.
Preventive measures:
+ Take care of the garden according to the technical process, apply fertilizers appropriately and fully, cover the roots in the dry season.
+ Destroy fallen diseased leaves.
+ Spray when the disease thrives, use Derosal 60WP, Antracol 70WP...
2.3 Leaf yellowing, root rot, pus discharge (Phytophthora palmivora + Pythium Complectens).
The disease causes strong damage when the garden soil is too wet, poorly drained, the fungus attacks the entire roots of the durian seedlings, making the roots unable to absorb nutrients, leading to the branches wilt, the leaves turn yellow and fall, then The tree is exhausted and dies.
Preventive measures:
Because the disease often attacks from the roots of the tree, it is very difficult to detect, until the disease is noticed on the tree, the condition of the durian seedlings has become serious, difficult to recover, so to prevent disease in the first place as well as limit the spread, should pay attention to the following issues:
* Before planting must clean, destroy plant residues, liming ... to limit pathogens available in the soil.
* Arrange 10% of backup seedlings for replanting.
* For young durian trees that have been seriously ill and died, they should quickly uproot all roots and destroy outside the planting area.
* Good drainage for the planting garden, do not let the garden be flooded to prevent water from overflowing on the planting garden.
* Infected plants, mix 40ml of Agri - fos 400SL in 8 liters of water + Mancozeb (mixed dose according to the manufacturer's recommendations) to spray through leaves and water or spray into the roots of plants 4 liters of medicinal water solution/root, treat 3 times, each time 15 days apart.
* Prevention of root rot: Mix 40ml of Agri – fos 400SL with a concentration of ̣0.5% and spray it periodically once a month in the rainy season and every two months in the dry season. Combined with aeration or root irrigation 4 times/year: At the beginning, middle and end of the rainy season, if the rainy season lasts, it is recommended to add one time aeration or watering the roots.
2.4 Corticium salmonicolor (Corticium salmonicolor)
The disease usually occurs on young branches and trunks, especially at the top of branches that are shaded from sunlight. First, on the surface of the bark, there are white mycelium that spread to form white patches, after the disease turns pink, the diseased branches are dry and dead.
Preventive measures:
- Prune branches, create a canopy for the garden to open, prune and destroy diseased branches
- Use drugs: Anvil 5SC, Validacin, Monceren 250 SC
2.5 Algae spot disease (Cephaleuros virescens)
Lesions on leaves and young branches have convex spots, gray-green form, gradually spreading when there is high humidity and enough light. Old lesions are red-green, raised, velvety. On the underside of the disease, damaged leaf tissue and even algae fibers can be seen. The disease causes the leaves to decrease photosynthesis and fall prematurely. Disease spots on branches are red-brown, making branches dry and weak, bark cracked, easy to create conditions for other fungal infections.
Preventive Measures:
* Proper care, fertilizing and watering adequately and balanced, pruning branches, creating a canopy for a clear garden, collecting and destroying fallen leaves due to disease.
* Spray on diseased stems, branches and leaves with copper-based drug solutions: Copper Oxychloride (Coc 85WP, Champion 77WP..), 1% Bordeaux solution....
2.6 Iron rust (Xanthomonas campestrippv)
Rust disease, also known as crab eye spot disease, damages durian. This disease is caused by the bacteria Xanthomonas campestricpv.cv.
At first, the disease is bright yellow, as small as a needle mark on young leaves. The disease then develops rapidly with light brown streaks. Diameter varies with cultivar. Crab's eye spot disease is shown on both sides of leaves, around the disease there is a bright yellow border and does not make leaves deformed or wrinkled.
In fact, this bacteria is easy to arise in high temperature conditions from 20 to 300C. Especially planting trees with too thick density, dense, not ventilated, lack of exposure to light, without regular human care.
The disease can be spread through many different ways such as: wind, rain, stinging insects, garden tools, etc. That is the cause for crab leaf spot disease to easily penetrate into the cells of plants and trees. cause adverse effects.
Preventive Measures:
Crab's eye spot disease has a rapid spread, especially in rainy and stormy conditions, it is necessary to pay attention to visit the garden regularly to detect the disease early.
Destroy and clean the garden to limit the spread of bacteria to surrounding plants.
Provide adequate nutrients for plants through the application of multi- and medium-micronutrient fertilizers.
Can use drugs to treat crab eye disease for durian trees such as: Kasura 47WP, Coc 85WP, NANO copper, champion 77WP ... spray 2-3 times, each time 3 - 5 days apart.
