Fruit pests - Ask Extension
Hello. I was hoping you could identify the apricot trouble. And secondly, these black things are on my currants clinging to leaf stems of which the l...
Knowledgebase
Fruit pests #556281
Asked April 27, 2019, 10:55 AM EDT
Hello. I was hoping you could identify the apricot trouble. And secondly, these black things are on my currants clinging to leaf stems of which the leaves were totally eaten. Thanks for your help.
Prince George's County Maryland
Expert Response
Hi- it's not possible for us to confirm the cause of the symptoms on the apricot fruit. Some possibilities:
1) shot hole disease; a fungal pathogen that overwinters on buds and infects leaves and fruits in spring. Would expect to see lesions on leaves that dry out and drop out leaving "shot holes" (often mistaken for insect feeding). Dormant fungicide sprays (e.g., fixed copper) are applied to help prevent this disease. Also, fungicide sprays at bloom and at fruit set are used by fruit producers to manage this disease. Thinning fruit and pruning to maximize air circulations within tree canopy can also be helpful. Remove and dispose of all diseased plant parts.
http://ipm.ucanr.edu/PMG/r5100311.html
2) if the spots are sticky this could be gummosis (plant sap pushed out of fruit) or even honeydew excreted by scale insects or aphids feeding foliage.
We don't know of insects that would defoliate currants at this time of year. There is a currant aphid (green in color) that can cause distortion in plant growth. They would be very noticeable. If deer frequent your yard it's possible they browsed your plants. We can't positively id the black things. It's possible that they are dead remains of adult seed corn maggots (not a currant pest) and unrelated to the plant damage:
http://extension.umd.edu/sites/extension.umd.edu/files/_docs/programs/ipmnet/11May13L.pdf (see page 7)
Jon
1) shot hole disease; a fungal pathogen that overwinters on buds and infects leaves and fruits in spring. Would expect to see lesions on leaves that dry out and drop out leaving "shot holes" (often mistaken for insect feeding). Dormant fungicide sprays (e.g., fixed copper) are applied to help prevent this disease. Also, fungicide sprays at bloom and at fruit set are used by fruit producers to manage this disease. Thinning fruit and pruning to maximize air circulations within tree canopy can also be helpful. Remove and dispose of all diseased plant parts.
http://ipm.ucanr.edu/PMG/r5100311.html
2) if the spots are sticky this could be gummosis (plant sap pushed out of fruit) or even honeydew excreted by scale insects or aphids feeding foliage.
We don't know of insects that would defoliate currants at this time of year. There is a currant aphid (green in color) that can cause distortion in plant growth. They would be very noticeable. If deer frequent your yard it's possible they browsed your plants. We can't positively id the black things. It's possible that they are dead remains of adult seed corn maggots (not a currant pest) and unrelated to the plant damage:
http://extension.umd.edu/sites/extension.umd.edu/files/_docs/programs/ipmnet/11May13L.pdf (see page 7)
Jon
