Pear scab
Venturia pirina
What is Pear scab (Venturia pirina)?
Pear scab, caused by the fungus Venturia pirina, is a worldwide fungal disease that primarily affects pear trees in temperate regions. It infects leaves, fruit, and young twigs, causing circular lesions ranging from olive green to dark brown to black. Initially velvety, the lesions later become cracked and corky. Fruit lesions measure approximately ⅛ inch in diameter, while leaf lesions are about 3/16 to 3/8 inch in diameter. Their irregular and diffuse margins differentiate them from other common spots on pear foliage.
How does a Pear scab (Venturia pirina) occur?
Pathogens overwinter primarily in infected leaves on the ground. In spring, primary spores (ascospores) are carried by air currents or splashing water to flowers, leaves, or fruit, causing initial infections. In high rainfall areas, the pathogen can also overwinter in twig lesions. Secondary spores (conidia) are produced on infected leaf or fruit surfaces, spreading the disease until conditions become dry, or the plant tissue becomes more resistant. Infection occurs rapidly between 55° and 75°F, with continuous wetness of at least 9 hours needed for initial infection at these temperatures.
Symptoms
1 - Plants Health
• Pear scab can cause fruit to become malformed, cracked, and unsightly, rendering it unusable. Severe early leaf infection can lead to defoliation, impacting the overall health and vigor of the tree. • Continuous infections of pear scab can weaken the plant's natural defense mechanisms, making it more susceptible to other diseases and pests.
2 - Impact on Soil
Pear scab can affect the decomposition rate of infected leaves, potentially impacting nutrient cycling in the soil.
Solutions
1 - Cultural Control Measures
• For backyard trees, remove and compost or destroy fallen leaves in autumn to limit disease levels. • Apply zinc and fertilizer-grade urea (or nitrogen source) to leaves in autumn to hasten leaf fall. • Add lime to leaf piles beneath the tree to reduce overwintering inoculum. • Choose pear cultivars with resistance to pear scab and other scab-resistant varieties. • If using sprinklers, irrigate between sunrise and noon to allow adequate drying time or adjust the angle of the sprinkler.
3 - Application of Fungicides
• There are several fungicides available for controlling pear scab, including propiconazole, myclobutanil, tebuconazole, and copper-based fungicides (such as copper octanoate and Bordeaux mixtures) sulfur, mineral oil, and neem oil. • It is important to carefully follow the instructions on the fungicide labels for proper usage, application rates, and safety precautions.
4 - Biological fungicides
• Biological fungicides for controlling pear scab include Bacillus subtilis, Trichoderma spp., Serenade® Garden, and Regalia®. • These products harness the power of beneficial bacteria or plant extracts to combat fungal diseases in an environmentally friendly way. • It is important to carefully follow the instructions on labels.
Susceptible Species
pearly everlasting
pearly everlasting
king's spear
pearlbush
pearlbush
pearlbush
pearlbush
spearmint
balsampear
prickly-pear
prickly-pear
prickly-pear
plains prickly pear
pearl millet
pearl millet
Chinese pearlbloom
callery pear
callery pear
callery pear
callery pear
common pear
common pear
common pear
dwarf pear
common pear
willowleaf pear
willowleaf pear
willowleaf pear
pear
pear
string of pearls
Snowy Day Blizzard pearlbush
water spearmint
Asian pear
Irish moss
string-of-pearls
Running Chuckleypear
Tall Pussytoes
Seep Spring Arnica
Halberd Leaf Orache
Red Pearls Anthurium
Pearl Laceleaf
King's Spear
Brazilian Prickly Pear
Garlic Pear Tree
Sacred Garlic Pear
String of peas
Bush Pear
Pink Wild Pear
Wild Pear
Giant Spear Lily
Pearlbush
Mountain Garcinia
Black Pearl
Santa Rita Prickly Pear
Prickly Pear
Prickly Pear
Tree Pear
Spearwood Bush
Pearcea
Pearcea
Pearcea
Avocado
Southern Pear
Spear Head
Tear-shrub
Spineless Hardy Prickly Pear
Purple Prickly Pear
Flowering Pear
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.
