Dutch Iron Disease II: anthrax

occurrence regularity

Bacteria winter on diseased remains in many ways. Primary and secondary infestations occur in the following year, when water is sprayed. After the formation of disease spots, bacteria continue to form, and continue to re-infect, forming a vicious circle of disease. High temperature, rainy season is more likely to occur.

symptoms

The disease mainly infects leaf tip and edge, and its pathological characteristics are similar to leaf spot. Early onset of wet brown lesions, sometimes pink mucus. After diffusion, it is semicircular or elliptical, reddish purple or dark brown spots, the center is pale brown or gray, after the onset will gradually expand, brown ring marks appear around, the spots will gradually shrink and dry. There are black particles on the spot. When the disease is severe, the whole leaf will turn yellow and wither.

control methods

1, timely drainage, prevent moisture retention, apply organic fertilizer, appropriate amount of phosphorus, potassium fertilizer.

2, timely pruning to remove sick and disabled bodies, unified deep burial or burning.

3. When continuous infection of bacteria causes Dutch iron disease, spraying is needed. Spray with stone sulfur mixture solution or suspension basic copper sulfate double solution (applied before disease onset), copper noble double solution, agricultural anti-water double solution, amicida suspension thiabendazole copper double solution.

The above is an introduction to the difference between Dutch iron and dragon blood tree and disease prevention. If you want to know more, please pay attention to the Four Seasons Plant Network!

Dutch iron diseases and their control

Iron disease I in Holland: the incidence of leaf spot

Pathogens of leaf spot disease usually live on the remains of the disease through the winter. Pathogens may be transmitted and infected in greenhouses, greenhouses, fields, and domestic potted plants during rain and watering. The microscopic size allows them to penetrate plants through wounds or stomata. In the environment of high temperature and humidity, the stomata of plants are enlarged, which makes them more susceptible to disease.

symptoms

At the beginning of the disease, the pathogen mostly invaded from the leaf edge and leaf tip. At first, it was a small green spot like water stain. If the weather was dry, the disease would be more obvious at the junction of disease and health, showing sunken black-brown semicircular spots; it was more dangerous under high temperature and high humidity environment, with obvious water stain and irregular leaf spot shape. With the increase of disease spots, there will be leaf tip drying, whole leaf necrosis, and even can see the fungus pus.

control methods

1. Eliminate sick and disabled bodies in time and burn them intensively.

2. Strengthen light transmission and ventilation. The humidity in the greenhouse should not be too high. Watering should avoid splashing. It is best to irrigate along the edge of the basin, which can reduce the chance of spreading infection.

3. After the disease is found, attention should be paid to spraying in the early stage, such as 77% wettable powder and water 1:500 solution, 30% copper oxychloride suspension 800 times solution, 47% Garinone wettable powder 800 times solution, 72% agricultural streptomycin or sulfomycin soluble powder 4000 times, etc.

Dutch Iron Disease II: Anthracnose Pathogenesis The bacteria spend the winter on diseased remains in many ways. Primary and secondary infestations occur in the following year, when water is sprayed. After the formation of disease spots, bacteria continue to form, and continue to re-infect, forming a vicious circle of disease. High temperature, rainy season is more likely to occur. symptoms

The disease mainly infects leaf tip and edge, and its pathological characteristics are similar to leaf spot. Early onset of wet brown lesions, sometimes pink mucus. After diffusion, it is semicircular or elliptical, reddish purple or dark brown spots, the center is pale brown or gray, after the onset will gradually expand, brown ring marks appear around, the spots will gradually shrink and dry. There are black particles on the spot. When the disease is severe, the whole leaf will turn yellow and wither.

control methods

① Timely drainage, prevention of moisture retention, application of organic fertilizer, appropriate increase in phosphorus and potassium fertilizer.

② Timely pruning and removal of sick and disabled bodies, unified deep burial or burning.

(3) Spraying is needed when Dutch iron disease is caused by continuous infection of bacteria. Spray with stone sulfur mixture solution or suspension basic copper sulfate double solution (applied before disease onset), copper noble double solution, agricultural anti-water double solution, amicida suspension thiobactam copper double solution.

Maintenance and Management of Potted Flowers in August

Every season has its own characteristics, this year's summer is unusually hot, in such a harsh environment, balcony, garden flowers will become very sad, if not pay attention to management, but also cause various diseases, serious and even cause death. So in the hot August, how should we manage potted flowers in the courtyard and balcony? The editor will analyze it for you from several aspects of daily maintenance.

Calceolaria

1. Watering

August, should be in the morning between 9 and 10 o 'clock, afternoon watering after 4 o' clock, keep the water temperature and soil temperature, temperature basically consistent. For acid-loving ornamental plant species, 0.1% ferrous sulfate can be added to the irrigation water. It should be noted that ornamental plants with dense villi on their leaves, such as caltrop flowers, giant rock flowers, iron cross begonia, hairy leaf begonia, etc., are not easy to evaporate after falling water drops on their leaves, which is easy to cause leaf rot, so only a small amount of spray can be applied; flower buds of leaf clusters of Helangium (Gerbera) and leaf cluster center of Clivia can not be drenched with water, dirty water flowing into leaf clusters will cause rotten heart; Pineapple must be watered less, sprayed more water, and injected water into leaf tube to meet its needs. This month, when watering and spraying potted plants, we must pay attention to loosening the soil, which can be done once every 10 days, otherwise it will lead to pot soil hardening due to repeated watering. For dormant and semi-dormant flower species, watering and spraying should be controlled to maintain a slightly moist pot soil. A relatively cool environment can be created by spraying water on the small environment around the flowerpot.

II. Fertilization

In August, the leaves of ornamental plants, such as Tortoise, Echinochloa, Rubber Tree, Spring Feather, Palm Bamboo, Red (Green) Gem, Araucaria, Jinshan Sunflower, Beautiful Needle Sunflower, Sanwei Sunflower, Fish Tail Sunflower, Bulrush Sunflower, Green Rose, Brazil Wood, Dutch Iron, Fortune Tree, Kidney Fern, Dew Tree, Chinese Grey Wood (African Jasmine), Cinnamomum Orchid (Pinganmu), Gold Coin Tree (Longfengmu), Syncorum, Green Emperor, Green Queen, Poinsettia, Daibernia Leaf, Goosefoot Wood, Peach Leaf Coral, Pocket Coconut, Variegated Leaf Wood, Octagonal gold plate, etc., can be applied with low concentration of liquid fertilizer, such as urea solution, flower fertilizer or cake fertilizer water. For the species with long flowering period, such as rose, white peony, jasmine, pearl orchid, Lagerstroemia, flower pomegranate, Milan, four seasons laurel, Japanese laurel, triangle plum, five-color plum, etc., as well as Dai, fingered citron, kumquat, lemon, rich seed, firethorn, golden marble, fruit pomegranate, southern Tianzhu, papaya, etc., in addition to ensuring nitrogen supply, appropriate amount of quick-acting phosphorus and potassium fertilizer should be applied, such as potassium dihydrogen phosphate. For potted grass flowers blooming in autumn, such as a string of red, chilianthus, dry chrysanthemum, marigold, peacock grass, dragon mouth flower, chrysanthemum, pocket sunflower, etc., thin liquid fertilizer can be applied once every half month to ensure that the leaves flourish after autumn. For flowers and plants in flower bud differentiation, such as camellia, tea plum, plum blossom, osmanthus flower, azalea, etc., low concentration of phosphorus and potassium fertilizer should be applied to the leaves. When topdressing ornamental plants with organic fertilizer, do not drip fertilizer on the leaves to avoid causing leaf decay. For safety reasons, spray water on the leaves in time after fertilization to wash away the fertilizer droplets that may adhere to the leaves. For ornamental plants in dormant and semi-dormant state, such as clivia, begonia, calla lily, cyclamen, daphne, aloe, longevity flower, purslane tree, crab claw orchid, sedum, purple triangle leaf sorrel, cactus, cactus, etc., all forms of topdressing should be stopped, otherwise it is easy to cause plant root rot or death.

Begonia semperflorens

III. Shade

In August, the summer heat is still thick, and shade management of potted flowers in the courtyard is still very important. For those cool ornamental plant species, such as turtle, spring feather, cherub, rubber tree, yellow sunflower, green giant, arrowroot, red (green) gem, palm bamboo, green radish, green king, green queen, orchid, pink bud leaf, pepper grass, pineapple, water flower, mirror grass, fern, buddha bamboo, phoenix tail bamboo, spider orchid, auspicious grass, pocket coconut, net grass, purple goose down, blood leaf orchid, silver hind bright silk grass, black leaf lotus, crystal candle, anthurium, begonia, Guanyin Rich bamboo, one leaf orchid, asparagus, purple calyx, etc., can continue to be given shade, 9 am pull on the sunshade net, after 4 pm and then removed. If the number of potted plants is small, it can also be moved indoors for 6 to 7 hours around noon. If conditions permit, it can also be moved to the shade of trees until mid-September and then moved out from the shade.

IV. Trimming

August, those vigorous growth, resistant to pruning, easy to germination of tree stump bonsai continue to be given toppling or pruning, such as elm, finch plum, Fujian tea, fig tree, white wax, water myrica rubra, boxwood seeds and so on. For roses, pomegranate flowers, Milan, etc., after each flower, to shrink shear. Potted chrysanthemum, to do a good job stripping buds and bud removal work.

V. Prevention and control of diseases and insect pests

August, to scale shell insects, citrus butterfly, rose sawfly, pink neck longicorn and other pests for control. Pay attention to the prevention of orchid leaf diseases, including anthracnose, gray mold, leaf blight and so on. Pay attention to the chrysanthemum aphid, leaf miner, moth and other control.