Common Diseases of Fatsia japonica and Their Control Methods

Chlorosis

Chlorosis is a common disease of Fatsia japonica. When chlorosis occurs, the leaves lose their green color and turn yellow. There are many causes of chlorosis in Fatsia japonica; it may be iron-deficiency yellowing or other causes. Generally, during cultivation, management should be strengthened and fertilization should be rational, which can treat chlorosis.

Leaf spot disease

Leaf spot disease of Fatsia japonica mostly occurs in summer. It mainly damages the leaves, causing spots to appear on the leaves and continuously expand, and in the end it may even cause the leaves to wither.

Leaf spot disease in Fatsia japonica is mostly caused by pathogenic fungi, whose spores spread with wind and rain. Generally, Fatsia japonica is prone to the disease under high temperatures and a muggy, humid environment. In terms of management, attention should be paid to strengthening ventilation, applying more organic fertilizer, and promptly destroying the withered leaves of Fatsia japonica.

If leaf spot disease occurs, some carbendazim solution can be sprayed for treatment.

Sooty mold

Sooty mold is a highly damaging disease and is generally caused by pathogenic fungi. The pathogen can overwinter on diseased leaves, or spread with the help of pests and rainwater, and is prone to breaking out in the hot, rainy seasons of summer and autumn. Sooty mold damages the leaves and branches of Fatsia japonica. When it occurs, the sooty mold should be removed in time, and some carbendazim solution should be sprayed for prevention and control.

Anthracnose

Anthracnose of Fatsia japonica damages the leaves, petioles and fruit stalks, causing spots to appear. When anthracnose occurs, the diseased branches and diseased leaves should be cut off in time, or chemical control should be carried out by promptly spraying chemicals; two kinds of chemicals can be sprayed alternately.

What diseases does Fatsia japonica have, and how are Fatsia japonica diseases prevented and controlled?

Fatsia japonica is a very popular indoor greenery plant. Because it stays evergreen all year round and its flowers are also very beautiful, it has good ornamental value. Cultivating a Fatsia japonica indoors to green up the indoor environment is a very good choice. Below, the editor will introduce to everyone what diseases Fatsia japonica has and how Fatsia japonica diseases are prevented and controlled.

Chlorosis of Fatsia japonica

Chlorosis of Fatsia japonica refers to the phenomenon in which part or all of the stems and leaves lose their green color and become yellow or yellow-green. There are many causes of chlorosis, among which the more common one is iron-deficiency chlorosis, generally solved through measures such as strengthening cultivation management and rational fertilization.

Leaf spot disease of Fatsia japonica

Leaf spot disease of Fatsia japonica mostly occurs in summer and damages the leaves. The spots mostly start from the leaf tip or leaf margin; in the early stage they are small light brown spots, and later they expand inward to form irregular large spots, grayish brown to reddish brown, with the margin having a dark brown ring line. The spots can cause 1/3-1/2 of the whole leaf to dry up, and many small black granular dots are scattered on the spots. The pathogen overwinters as mycelium and pycnidia in diseased leaves and fallen diseased leaves, and the following year produces conidia that become the primary infection. With infection, the spores spread with wind and rain. The suitable temperature for pathogen development is around 27°C. High temperatures, high humidity, a damp and muggy environment, shade and poor ventilation, and weak plant growth all favor the occurrence of the disease. Strengthen cultivation management, apply more organic fertilizer, and in winter remove diseased fallen leaves and bury them deeply or burn them. Spray chemicals in the early stage of the disease: 1:2:100 double-strength lime Bordeaux mixture, or 50% carbendazim 800-**** times solution, or azinphos-ethyl 500 times solution.

Sooty mold of Fatsia japonica

Sooty mold of Fatsia japonica belongs to the sooty mold fungi in the subphylum Deuteromycotina of the fungal kingdom. The mycelium is dark brown, bead-like, and creeping on the leaf surface. Conidia have diverse forms: single-celled, two-celled or muriform. The pycnidia are upright, long club-shaped, 280-455 micrometers long and 42-50 micrometers wide; there are also nearly spherical pycnidia, 49-70 micrometers in diameter. The pathogen overwinters as mycelium on diseased leaves, diseased branches, etc. It is spread by scale insects and wind and rain. After large numbers of scale insect larvae appear in June, their excreted sticky secretions serve as nutrients and induce the sooty mold pathogen to multiply in large numbers. Late June to early and mid-September is the peak damage period of scale insects; at this time high temperature and high humidity favor the occurrence of this disease. It mainly attacks leaves and branches. On the front of the leaves and on the branches and petioles, a layer of black soot-like powder covers the surface, affecting photosynthesis. The soot-like powder can sometimes be peeled off or washed away by heavy rain. For sooty mold, promptly wipe off the sooty mold with a clean cotton cloth, and spray fungicides such as 25% carbendazim wettable powder 600-800 times solution, 50% thiram 800-**** times solution, or 70% zineb 600 times solution for prevention and control.

Scab-type anthracnose of Fatsia japonica

Scab-type anthracnose of Fatsia japonica is a new symptom of Fatsia japonica anthracnose, and can damage leaves, veins, petioles and fruit stalks. The typical symptom of leaf spots is that the front is grayish white and slightly thickened like scabies, while on the back the round wart-like protrusions are obvious, and the middle of the spot cracks. Its control method is first to promptly cut off diseased plants and diseased leaves to reduce the pathogen, and second is chemical control. Commonly used chemicals include 25% carbendazim (bromothalonil) emulsifiable concentrate 500 times solution or 80% anthracnose thiram 800 times solution, sprayed on the plants once every 2 weeks; 3-4 times can basically bring it under control, and alternating use of the two chemicals will give better control results.

Pest and disease control of Fatsia japonica

        Fatsia japonica is an evergreen shrub of the Araliaceae family. Its leaves are large and alternate, star-palmately lobed, thick, glossy, with serrated or wavy margins. The umbels are gathered into terminal panicles, and the flowers are white. The flowering period is October-November. The berries are spherical, purple-black, covered with white powder, and mature in May of the following year. When planting, it can be propagated by sowing, cuttings or division.
       1. Causes of yellow-brown spots 
       Through observation, we found that yellow-brown spots had appeared on the leaves, petioles and stems of Fatsia japonica. The spots on the leaves were round, and later expanded into irregular large patches. After reaching a certain number, the leaves began to curl and wither. At the same time, we also found that the spots were contagious; the Fatsia japonica beside the diseased plant had also been infected with spots. Through observation, searching for information, and consulting experts, we learned that the Fatsia japonica had anthracnose. 
       2. Prevention and treatment of Fatsia japonica anthracnose 
      Spray Bordeaux mixture regularly, or use 50% carbendazim wettable powder 1000 times solution for spray control. In addition, for seriously infected plants and leaves, thorough pruning can be adopted, followed by burning off-site. 
       3. Control of scale insect damage 
       Control methods: A. When it first occurs, it appears in spots and patches; thoroughly cut off and burn the branches with insects, or manually brush and wipe the insect-infested branches to remove the source of insects. B. Before the nymphs secrete the waxy scale during the dispersal and transfer period, chemical control is more advantageous. To improve the insecticidal effect, it is best to mix 0.1-0.2% laundry powder into the chemical solution. 
       Available chemicals:
   (A) Pyrethroids: 2.5% deltamethrin or kungfu emulsifiable concentrate or 20% fenpropathrin emulsifiable concentrate 4000-**** times solution, 20% fenvalerate emulsifiable concentrate 3000-4000 times solution, 10% cypermethrin emulsifiable concentrate 1000-2000 times solution.
   (B) Organophosphorus insecticides: 50% monocrotophos or parathion or demeton emulsifiable concentrate 1500-2000 times solution, 50% malathion or fenitrothion or phenthoate emulsifiable concentrate 1000 times solution, 40% omethoate or dimethoate or dimethoate emulsifiable concentrate or 50% dichlorvos emulsifiable concentrate 800-**** times solution.
   (C) During the damage period, in combination with the control of other sap-sucking pests, systemic insecticides can be applied by painting the trunk and wrapping it. Using monocrotophos or omethoate or demeton etc. at 20-50 times solution has good results.