My corn plant has been pretty healthy for the past six months and then today suddenly I saw two brown spots on one leaf (incidentally this leaf doesn't look as healthy) and darker brown spot on another. They are usually covered with soil particles, giving them a dusty appearance. Entire leaves may be covered with the thin, white layer of fungus, which may be mistaken for dust. Holcus leaf spot is caused by the bacteria Pseudomonas syringae pv. There have been several reports of corn turning white in different parts of Illinois. Most commonly, you'll find the white residue in these areas first, but if your problem has advanced, these pests will spread out to more joints, foliage crowns, or further out along the foliage and down stems. However, as the fungal growth spreads, the white stuff can cover the entire plant. They eat the stalks of corn plants that are growing slowly due to poor nutrition. colored spots on them that have worsened and turned a darker brown with larger spots. Symptoms of anthracnose are fairly common early in the season on lower leaves and later in the season on upper leaves. It usually occurs in patches and is more common in corn following corn fields. European corn borer is a 1-inch-long tan or brown caterpillar sporting rows of dark brown spots and a dark brown head. If you have followed and repeated the steps above and the Mealy problem is still persistent, there are insecticides (referred to as systemic insecticides) that can be used to treat the problem. I now have white furry mold growing on the plants and they are looking VERY unhealthy!!! Young foliage is most susceptible to damage. Powdery mildew on houseplants is a fungal disease. This residue is either the egg sacs of the mealybugs or the pests themselves. However, the following measures can be taken to help ensure that a problem doesn't worsen. Temperatures below the ideal range can lead to more occurrences of flecking, so move the plants to a warmer location if necessary. If you notice white spots on the leaves of your corn plant, it's likely due to flecking, a condition that requires a stricter care regiment. Missouri Botanical Garden: Dracaena Fragrans, Penn State University Extension: Dracaena Diseases, Missouri Botanical Garden: Indoor Plants or Houseplants, University of Missouri Extension: Caring for Houseplants, Plant Care for Dracaena Fragrans "Massangeana", Yellowing Leaves on a Dracaena 'Massangeana'. Also causes brown dusting on leaves and blooms. Eyespot presents as many circular to oval spots on the leaf which may coalesce to form large areas of dead tissue. Spray this solution on the plant leaves and wipe them clean again; this will serve to further clean off more eggs that may have been left behind. In addition, Friday (4/20/12) numerous calls from the Hollandale, Indianola, and Shaw areas confirmed the presence of Holcus leaf spot in most corn fields throughout the central Delta. If you see a white, powdery fungus on the leaves of your plants, it is likely they have powdery mildew. Many pests see corn plants as a big, luscious salad. It appears that some sort of stress may trigger the symptoms. There are two fungal pathogens that cause GLS: Cercospora zeae-maydis and Cercospora zeina. If you notice brown spots on the tips and edges of leaves, this could be … Source : Purdue.edu. A plant that is struggling in any way is more prone to be attacked by pests of many kinds including mealybugs. Dracaenas are sensitive to fluoride, so it’s best to use filtered water. A weird spot showing up in corn fields is lesion mimic (Figure 4). The two leaves are relatively new leaves. Powdery Mildew doesn't kill plants, but greatly weakens them. If you come into contact with the infested plant, it's important to wash your hands before touching any of your other houseplants. They are best cleaned off with baby wipes or a wet paper towel. Although I heard of no reports in 2009, this spot was around in 2007 and 2008. Corn plant (Dracaena fragrans) is a tropical evergreen plant that's commonly grown as a houseplant. Powdery mildew is a fungal disease. CORN. This article is accurate and true to the best of the author’s knowledge. If an area of a particular plant has a spot that appears to be the epicenter of the infestation—dracenas (sometimes called corn plants) will commonly get mealybugs that are nestled down in the new growth crowns—cut off any of the infested crowns. Due to the ease of contamination, mealybugs are also easily spread to other plants that may be touched after the infested plant has been touched. Holcus leaf spot of corn. The good news is that the poor thing’s prognosis for recovery with reasonable treatment is excellent. The haloed spots give the appearance of an “eyespot.” Corn Plant Care Guide Light. Damage Symptoms: Beetles feed on the edges of leaves and stems, producing notched holes in the leaves. Keep your plant clean by wiping the leaves down with baby wipes on a regular basis; remove any debris and/or potential pests that you notice. Water and nutrient imbalances sometimes go hand in hand for houseplants because the amount of water present in the soil impacts how the plant is able to absorb nutrients. They lay eggs along the foliage that they inhabit and easily contaminate anything that touches them. As the downy spot progresses, the upper sides of the leaves become chorotic, that is, show yellowish spots that will eventually turn brown. Affected leaves will fall from the tree by early August. Mealybugs give the appearance of lint due to a waxy outer residue that they secrete for camouflage and protection. Those white spots on the plant leaves are fungal structures and spores that thrive in the warming temperatures and rains of spring. If you know what kind of plant you're dealing with and maintain it with care, mealybugs should be of little to no worry.