Downy mildew
Peronospora sparsa
What is Downy mildew (Peronospora sparsa)?
Peronospora sparsa is a plant pathogen belonging to the group of Oomycetes causing highly destructive diseases like downy mildew. These fungal infections can also affect other closely related Rubus species, such as blackberry, raspberry, and boysenberry. blackberries, and raspberries. It primarily infects leaves but can also affect stems and fruits. Symptoms include yellow lesions on upper leaf surfaces turning brown, accompanied by fluffy growth on the underside due to pathogen sporulation.
How does Downy mildew (Peronospora sparsa occur)?
Peronospora sparsa survives as oospores and forms sporangia that produce zoospores. Germination requires water. Pathogens enter plants through stomata or by penetrating the surface. They create haustoria to extract nutrients. Fluffy symptoms appear on leaf undersides. Pathogens spread through air, water, and tools, with some seed transmission. The optimum temperature for germination, infection, and spore production is around 10-20°C. Overwintering oospores develop late in the season, found in soil or on living host plants.
Symptoms
1 - Effect on Plants
1. Downy mildew can weaken plants, leading to reduced growth and overall vigor. 2. Infected plants can impact photosynthesis and nutrient uptake. 3. Severe infections can cause premature leaf drop, leading to reduced plant health and productivity. 4. Downy mildew can significantly reduce crop yields, affecting agricultural production and economic outcomes.
2 - Soil Health
1. Diseased plant material, when decomposed, may affect the natural nutrient cycling processes in the soil. 2. Downy mildew pathogens can alter the microbial balance in the soil, potentially impacting beneficial microorganisms.
3 - Impact on Environment
1. Pathogens can spread rapidly, either through wind, water, or human activities, affecting nearby plants and potentially leading to broader disease outbreaks.
Solutions
1 - Cultural Control
• Choose resistant cultivars when available to prevent downy mildew. • Purchase seeds from reputable nurseries to avoid infected plants. • Prune plants to enhance air circulation and reduce moisture on leaves. • Adequately space row crops to ensure proper airflow even as they mature. • Avoid overhead irrigation that wet leaves and opt for drip irrigation to water plants at ground level. • Apply a 3-inch layer of mulch around plants to prevent soil splashing and maintain moisture balance. • Clean up and discard plant debris, leaves, and infected material to eliminate overwintering sites for downy mildew spores. • Quarantine new plants for 14 days before introducing them to the garden or greenhouse.
2 - Biological Control Agents for Downy Mildew
• Trichoderma spp competes with downy mildew and produces antifungal compounds. While Bacillus subtilis colonizes plant surfaces and produces antimicrobial compounds. • Neem oil, garlic extract, and cinnamon oil exhibit antifungal properties against downy mildew, providing alternative control methods.
3 - Chemical Control
1. Copper-based Fungicides: Effectively control downy mildew, but repeated use can cause soil copper accumulation. 2. Systemic Fungicides: Absorbed by plants for internal protection against downy mildew. Rotate fungicides with different modes of action to prevent resistance.
Susceptible Species
Mocha Rose Big Leaf Maple
Rose Marie Magnolia
Candied Apple Flowering Crab
Dolgo Apple
Donald Wyman Flowering Crab
Louisa Flowering Crab
Melrose Apple
Red Jewel Flowering Crab
Sentinel Flowering Crab
Snowdrift Flowering Crab
desert rose
swamp milkweed
swamp milkweed
swamp milkweed
swamp milkweed
shrubby evening primrose
rose peashrub
squarrose sedge
rose glory bower
Cumberland rosemary
rose verbena
rose vervain
rock rose
rock rose
rock rose
rock rose
rock rose
Christmas rose
Christmas rose
scarlet rose mallow
Neches River rosemallow
common rose mallow
rose mallow
rose mallow
rose mallow
common rose mallow
common rose mallow
fringed rosemallow
striped rosemallow
rose of Sharon
rose of Sharon
rose of Sharon
rose of Sharon
rose of Sharon
rose of Sharon
rose of Sharon
rose of Sharon
rose of Sharon
rose of Sharon
rose of Sharon
rose of Sharon
rose of Sharon
rose of Sharon
rose of Sharon
rose of Sharon
rose campion
paper-rose
oleander
oleander
common evening primrose
evening primrose
evening primrose
evening primrose
Missouri evening primrose
dwarf evening primrose
evening primrose
evening primrose
evening primrose
white evening primrose
white evening primrose
kerosene bush
rose cactus
tuberose
rosemary mint
rose moss
primrose
Bee's primrose
primrose
primrose
hardy primrose
primrose
primrose
primrose
primrose
rosebay rhododendron
roseshell azalea
hybrid tea rose
shrub rose
hybrid tea rose
shrub rose
shrub rose
shrub rose
shrub rose
shrub rose
shrub rose
shrub rose
shrub rose
shrub rose
shrub rose
shrub rose
shrub rose
hybrid musk rose
banksia rose
banksian rose
miniature rose
hybrid rugosa rose
hybrid wichurana rose
shrub rose
Carolina rose
kordesii rose
shrub rose
shrub rose
shrub rose
shrub rose
climbing polyantha rose
shrub rose
hybrid tea rose
large-flowered climbing rose
hybrid tea rose
large-flowered climbing rose
kordesii rose
large-flowered climbing rose
large-flowered climbing rose
floribunda rose
mini-flora rose
shrub rose
large-flowered climbing rose
shrub rose
floribunda rose
hybrid rugosa rose
hybrid tea rose
rose
shrub rose
floribunda rose
miniature rose
floribunda rose
floribunda rose
hybrid tea rose
floribunda rose
rugosa rose
floribunda rose
hybrid tea rose
hybrid tea rose
floribunda rose
hybrid tea rose
climbing miniature rose
hybrid tea rose
floribunda rose
shrub rose
shrub rose
floribunda rose
Cherokee rose
large-flowered climbing rose
hybrid perpetual rose
hybrid tea rose
shrub rose
shrub rose
hybrid tea rose
shrub rose
shrub rose
shrub rose
hybrid tea rose
large-flowered climbing rose
hybrid tea rose
large-flowered climbing rose
hybrid tea rose
shrub rose
hybrid tea rose
shrub rose
hybrid rugosa rose
hybrid rugosa rose
multiflora rose
seven sisters' rose
China rose
floribunda rose
hybrid moyesii rose
large-flowered climbing rose
shrub rose
damask rose
shrub rose
swamp rose
hybrid tea rose
hybrid tea rose
floribunda rose
grandiflora rose
shrub rose
shrub rose
shrub rose
shrub rose
shrub rose
shrub rose
shrub rose
shrub rose
climbing miniature rose
Portland rose
sweet briar rose
rugosa rose
Japanese rose
miniature rose
miniature rose
miniature rose
miniature rose
miniature rose
miniature rose
miniature rose
mini-flora rose
miniature rose
miniature rose
miniature rose
miniature rose
miniature rose
miniature rose
miniature rose
hybrid rugosa rose
shrub rose
miniature rose
shrub rose
prairie rose
hybrid rugosa rose
climbing tea rose
hybrid tea rose
polyantha rose
hybrid rugosa rose
hybrid multiflora rose
hybrid multiflora rose
hybrid tea rose
grandiflora rose
floribunda rose
floribunda rose
floribunda rose
large-flowered climbing rose
large-flowered climbing rose
kordesii rose
Manchu rose
bourbon rose
shrub rose
landscape shrub rose
rose
rose gentian
Plymouth rose gentian
rose-gold pussy willow
rosemary
rosemary
rosemary
rosemary
rosemary
rosemary
rosemary
rosemary
creeping rosemary
rosemary
rosemary
rosemary
rosemary
rosemary
rosemary
rosemary
snowrose
snowrose
snowrose
rose spirea
Cape primrose
Baldhip Rose
Bog Rosemary
Canada Rosebay/ Rhodora
Clustered Wild Rose
Common Wild Rose
Sunset rock rose
hybrid Lenten rose
hardy hibiscus
fairy primrose
primula
Nootka rose
cape primrose
Northern Bog Rosemary
Glaucous-Leaved Bog Rosemary
James Bay Bog Rosemary
Dwarf Contorted Suncup
Little Rose
Rosendahl's Golden-Saxifrage
Pink Rockrose
Desert Rose
Desert Rose
Double Flower Desert Rose Hybrid
Desert Rose
Desert Rose
Desert Rose
Desert Rose
Adenium
Black Desert Rose
Variegated Desert Rose
Yellow Desert Rose
Desert Rose
Tuberose
Red-centred Hibiscus
Bog Rosemary
Smooth-barked apple
Baby Sun Rose
Sea Rosemary
Elephant creeper; Woolly Morning Glory
Coogera
Swamp Milkweed
Rose of the Andes
Rose of Venezuela
Rose of Venezuela
Rose of Venezuela
Panama Flame Tree
Rose cascade
Roselings
Red Shower Tree
Hairy Rockrose
Gum Rockrose
Sageleaf Rockrose
Rockrose
Thailand Rosewood
Black Rosewood
Pink Cloud
Tropical Rose Hydrangea
Wild Rosemary
Rose of Siam
Malay Rose
Malay Rose
Malay Rose
Sturt's Desert Rose
African Rosemallow
Scarlet Hibiscus
Swamp-rose Mallow
Confederate Rose
Hibiscus
Blue Hibiscus
Rose Bud Jasmine
Japanese Jasmine
Jasminum sambac Rosebud
Double Kerria
Primrose Tree
Rose cactus
Pink Rose Cactus
False Primrose
Floating Primrose Willow
Primrose Willow
Swamp Primrose
Thai Rose
Woodrose
Large Woodrose
Yellow Merremia
Beach Evening Primrose
Missouri Evening Primrose
Evening Primrose
Pink Evening Primrose
Rose-colored Lead-wort
Moss rose
Primrose
Stansbury's Cliffrose
Rose Cactus
Rock Rose
Rose Grass
Hong Kong Rose
Rose Myrtle
Panama Rose
Panama Rose
Rose
Lady Banks Rose
Father Hugo Rose
Wild Rose
Panama Rose
Ruddy Rose
Ruddy Rose Pink
Rosemary
Cape Stock-rose
Water Cherry
Rose apple
Wild Rose Apple
Yellow jacaranda
African Bonsai
False Rose Tree
Native Rosemary
Primrose
Rose Mallow/Hardy Hibiscus
Rock Rose
Rosemary
Brazilian Rock Rose
Primrose Jasmine
FAQ
Do shade growing plants need any Sunlight?
Shade growing plants do need sunlight, although they require less than other plants. They need some direct sunlight each morning to help them photosynthesize and grow properly. Also, indirect sunlight throughout the day helps them stay healthy. Shade growing plants will benefit from the sunshine, but if they get too much or too little, then they can suffer the consequences. It's important to pay attention to the needs of your plants so that you can provide them with the proper light for optimal growth.
How often should you water indoor plants?
Indoor plants should be watered when the soil feels dry to a depth of about two inches, usually about once a week. A helpful technique to determine your plants' watering needs is to feel the soil before and after watering to get a sense of how long it takes to dry out. An important note to remember is that some plants require less water than others, and it's best to research the specific needs of your individual plants. Likewise, if your home is very dry, you might need to water more often as the lack of moisture can stress the plants and lead to problems like brown leaves and wilted stems.
Can my monstera plant get root rot?
Yes, a plant can get root rot. Root rot is a fungal disease that can be caused by over-watering, poor soil drainage, or high humidity levels in the air. Signs of root rot include yellowing leaves, wilting and stunted growth, and damaged or browning root systems. Sometimes it is difficult to detect root rot until the plant is removed from the soil, as the problems are mainly below the soil surface. Treating root rot usually involves removing the affected parts of the plant and replanting the unaffected ones.
Can I put my Monstera outside in summer?
No, you should not put your Monstera outside in summer. Monstera plants need warm, humid air to thrive, and direct sunlight can scorch their leaves. Instead, put your Monstera in a bright, sunny spot with indirect light, making sure the sun never directly hits the leaves. During the summer, keep your Monstera's soil damp and mist it occasionally to keep the leaves hydrated. At nighttime, keep the temperature around 16 - 21°C (60 - 70°F). You can definitely take your Monstera outdoors for short periods of time, just make sure to bring it back in if it starts to get too hot.
What happens if my monstera plant gets too cold?
If your monstera plant gets too cold, it will become vulnerable to pests, disease, or other damage. Cold temperatures can damage the leaves of the plant, causing them to become spotted or limp. The roots of monstera plants may also suffer in cold temperatures, leading to root rot or other diseases. Belonging to the tropical family, monsteras are used to warm environments and do not do well in cold temperatures, so it is important to ensure your plant is kept in conditions that suit their needs.
Is it possible to grow a vegetable garden in a small space?
Yes, it is possible to grow a vegetable garden in a small space. Gardening in a small space can be as simple as growing a few containerized plants in pots and raised beds, or as elaborate as vertically stacking planters, hanging pouches, and hanging baskets on a wall, railing, or fence. Regardless of the size of the space you are working with, some simple techniques such as companion planting, organic fertilizers, and water conservation can help you get the most out of your small vegetable garden.
Is peppermint herb green good for digestion?
Peppermint herb is indeed beneficial for digestion. The flavonoids in the herb support digestion by reducing inflammation in the digestive track, aiding in digestion and relieving indigestion, heartburn, and even the symptoms of irritable bowel syndrome. Additionally, peppermint is naturally rich in menthol, which helps to relax the muscles of the stomach, aiding in the digestion of food. Peppermint herb can be consumed in a variety of forms, such as teas, tinctures and capsules, as well as by adding the herb to food or directly to water or tea.
Should peppermint herb green be consumed daily?
No, peppermint herb green should not be consumed daily. This is because it contains high levels of menthol, which can be toxic if taken in large doses. Additionally, consuming large amounts of peppermint herb green could interfere with the absorption of essential minerals and vitamins, potentially causing vitamin deficiencies. For these reasons, it is best to consult with a doctor before incorporating peppermint herb green into your daily diet.
