A peach tree bacterial perforation disease
In addition to harming peach trees, pathogens that cause bacterial perforation disease in peach trees can also harm stone fruit plants such as elm plums, cherries, red leaf plums, and other stone fruit plants. Perforation disease can cause a large number of leaves to fall, and severe ones can lead to the death of branches, reducing the landscape effect and ornamental value of plants.
Hazard characteristics: mainly harmful to leaves, but also can infect fruits and branches. After leaf infection, it initially produces light brown water-stained spots at the proximal veins on the back of the leaf, and later also appears on the front of the leaf, mostly at the tip or leaf margin. Later lesions enlarge into purple-brown to blackish-brown round or irregularly shaped spots with edges. There is a water-stained yellow-green halo around the spot. Finally, the lesion withers, a circle of cracks is generated at the junction of the disease and health, and the central tissue of the plaque falls off and forms a perforation. Sometimes several spots are connected into one large spot. After scorching off, a large hole with an untidy edge is formed. Severely leads to early leaf defoliation. Most of them develop symptoms from April to mid-May, and the onset is peak in August. The temperature is low, the tree is strong, and the incubation period is long; on the contrary, the incubation period is short and the onset is fast. 24 ~ 28 °C is the appropriate temperature for the onset of the disease. After the first infection, it will occur every year after that, and the degree of occurrence in the second year depends on the tree posture, weather, management, etc.
Prevention and control methods:
1) Strengthen the management of peach trees, enhance the tree posture, and remove diseased branches, fruits and leaves.
2) Before the onset of the disease, it can be sprayed with 800 times the liquid of liangguoan and used every 15 days.
3) At the beginning of the occurrence of the disease, it is controlled with 800 times methyl tolbutazine plus 600 to 800 times of agricultural chlormycin or 500 to 600 times of carbon trantramin plus 4000 times of neophytinomycin spray.
4) Spraying or soil paclobutrazol in the peach tree where the growth is relatively vigorous can significantly reduce the harm of perforation disease.
2. Peach tree strain
Peach tree flow gum disease, also known as wart disease, resin disease, rot disease, can be divided into invasive flow gum disease and non-invasive flow gum disease, is a very common disease, can cause premature tree aging, leaves yellow, serious can cause dead branches, dead trees, its trunk and main branches and twigs can occur. The disease can also harm peaches, plums, apricots, peaches, cherries and other flower shrubs.
Hazard characteristics: Non-invasive fluid glue is caused by mechanical damage, insect wounds, sunburn, etc. Wound glue, mainly occurs on the main trunk and large branches, and small branches can also be diseased when severe. The initial disease part is slightly swollen, and then secretes translucent, soft gum, after rain, the glue is heavy, and then the contact with the air becomes brown, becoming a crystal soft patch, and then drying into a reddish brown to tea-brown hard patch, as the number of glue increases, the diseased cortex and xylem gradually become brown and decayed (but no pathogens are produced). As a result, the trees are getting weaker and weaker, and in severe cases, dead trees are caused, the incidence of disease is heavy in the rainy season, the incidence of older trees is heavy, and the incidence of young trees is light.
Infected glue mainly harms the root neck, trunk, branches and other parts, but also infects the fruit, the pathogen invades the peach tree when the new shoots, the new shoots produce nodular protruding spots centered on the skin holes, but do not flow gum, in May of the following year, the tumor skin cracks and overflows the colloidal liquid, which is a colorless translucent stick, and then becomes a tea-brown hard block, and the diseased part is concave into a round or irregular plaque, which scatters small black spots. Perennial branches are susceptible to disease, resulting in blister-like bulges, and brown glue can ooze from the diseased parts, which can lead to branch ulcers or even death. Peach fruit disease occurs brown rot, on which small particles are densely packed, and white lumps flow out when wet. It overwinters in diseased branches with mycelium and conidia, and emits conidia from late March to mid-April of the following year, spreading with the wind, mainly through wound invasion, but also from skin holes and lateral buds. There are two peaks of incidence of infected fluid gum disease in 1 year, the first time in early May to early June, the second time in early August to early September, after which it will no longer be infected, and the most favorable time for the invasion of pathogens is gradually thrombolytic in the branches and cortex cells, after the formation of skin holes, so it is better to prevent and control this disease to the growth period of new shoots.
(1) Strengthen cultivation management, enhance tree potential, and improve disease resistance. Apply more organic fertilizer to diseased trees, increase phosphorus and potassium fertilizers in an appropriate amount, and control nitrogen fertilizers in the middle and late stages. Prune reasonably to maintain a stable tree stance. Drain well during the rainy season to reduce soil moisture. Timely summer shearing, improve ventilation and light transmission conditions, while preventing and controlling other pests and diseases, especially the branches and pests of peach trees, reducing pests and diseases and mechanical wounds.
(2) Eliminate the source of overwintering bacteria. In winter, the garden is disinfected, the rotten cortex and xylem of the rubber block and its lower part are scraped and burned centrally, and then sprayed with 5 baume degrees of stone sulfur compound disinfection; before the peach tree germinates, the tree body is sprayed with 5 baume degrees of stone sulfur compound or 60 to 100 times the rotting spirit killing activity of the pathogen.
(3) Spray in a timely manner during the growing season. Late March to mid-April is the period when conidia are produced by invasive fluid gum disease, and 1500 times methyl tolbutazine or 1000 times carbendazim or 600 times beautiful gogandhane + osmotic silicone can be sprayed for prevention. On the eve of the peak period of the disease, spray 1 time every 7 to 10 days 1000 times bacteriotoxic killing or bacteriological detoxification, sterilization, etc., alternately used, spray 2 to 3 times, the onset period first use a knife to scrape off the dry glue and old skin of the disease, and use a knife to cut several times, and then apply Liang Guoan 10 to 50 times liquid + silicone or ulcerative essence solution, the application area should be greater than 1 to 2 times the incidence area, and then apply it again every 7 to 10 days.
Three peaches a little spotted leafhopper
Hazard characteristics: Peach spotted leafhopper, belongs to the order Homoptera, leafhopper family. It mainly harms all kinds of peach trees, osmanthus flowers, cherry blossoms, sea trees, moon seasons, plum blossoms, cherries, begonias, grapes, pines and other plants. Adults overwinter in evergreen leaves or weeds. The following year, from April to May, it began to migrate from the wintering place to the young leaves to suck the hazard. Small yellow-white dots initially appear on the damaged leaves, and in severe cases, the spots are connected, making the whole leaf pale and causing the leaves to fall off early. Adults lay their eggs in the main veins of the leaf dorsal, mostly near the base, and a few in the petiole. The female produces 46 to 165 eggs. After the nymphs hatch, they flock to the back of the leaves to suck on the hazards, and when frightened, they quickly crawl wildly. The first generation of adults begins to occur in early June, the second generation in early July, the third generation in mid-August, and the fourth generation in early September. This generation of adults overwinters in October among green grasses, under the bark or in evergreens such as pines.
(1) Scrape the warp skin in time before the adult insects emerge from the sting, remove the leaves and weeds, and reduce the source of overwintering insects.
(2) The first generation of nymph hatching in late May and the second generation of nymph hatching from late July to early August. You can choose 5% high-efficiency cypermethrin emulsion 2000~ 3000 times liquid or 20% rapid killing butadiene emulsion 3000 times liquid spray control.
Source New technology for fruit tree planting