Those who are fortunate enough to have their own citrus trees and experience the joy of picking their own oranges (Citrus sinensis) or lemons (Citrus limon) may anticipate having excellent fruit for either eating or cooking. When citrus fruit develops black spots, this is a clear indication that something went wrong during the production process. Even though they are upsetting, the black spots are really indicators that may assist you in determining what the issue is with your citrus tree and how you can avoid it in the future.
Known Citrus Diseases
Determine the cause of the issue with your citrus fruit by determining the kind of mark that is present on the fruit. The vast majority of illnesses that result in spots really cause the fruit to rot. Alternaria rot, often known as black rot, is a kind of decay that leaves lemons with a soft, dark brown or black decay and navel oranges with a dark, hard decay. It often manifests itself after the fruit has been preserved, although it may also attack before to harvest in rare cases.
The areas of rot may be seen all the way through the apple. A different condition known as bacterial blast, often known as citrus blast, causes the fruit peels to become covered with tiny black dots. In the state of California, this illness is nearly never seen anywhere else save in the Sacramento Valley. Fruit that has been kept and seems to have black pits may have been afflicted with a disease known as septoria, according to the Statewide Integrated Pest Management Program at the University of California.
Citrus Tree Pests
Insects are a contributing factor in the development of sooty mould, which is characterised by the appearance of fuzzy, dark growths of mould on the surface of citrus fruit peels. When you find this disease on your trees, it is likely because they have been attacked by insects that feed on plant juices, the most common of which are citrola scale, cottony cushion scale, mealybugs, aphids, or whiteflies. When you find this disease on your trees, it is likely because you have detected it.
Honeydew is a sticky material that is produced by these insects as they sip the fluids. This honeydew serves as fuel for the mould to develop as it feeds on the insects. After removing the mould using a mixture of soap and water, the fruit that has been afflicted by the ailment may still be consumed. The elimination of the insects puts an end to the issue.
Black Mold on Oranges Management
Bacterial blast, which is prevalent in the Sacramento Valley, is carried by the wind throughout the winter and early spring months. However, attempting to treat this illness on your own may quickly become expensive. It is possible that using a spray that is designed to combat brown rot or septoria will help avoid bacterial blast. Maintaining well-pruned trees in the spring and applying fertiliser in the late spring or early summer helps keep a tree from producing an excessive amount of new growth in the autumn, which can make the infection worse.
The University of California Agriculture and Natural Resources advises that the best way to protect your trees from Alternaria rot is to maintain them healthy and robust. This will allow the trees to better withstand the toxin that is the root of the illness. Imazalil is a chemical that may be applied to the trees after they have been harvested in order to treat them against the disease.
One To Watch For
The dreaded disease known as citrus black spot is still being monitored by agricultural specialists in the United States. According to the University of Florida IFAS Citrus Extension, the illness caused by the fungus has been impacting citrus trees in Florida since the spring of 2010, and it has rapidly been spreading across the state. It has also been found in a great number of other tropical or subtropical places all over the globe and is very likely to continue to expand. This disease causes the fruit to develop a variety of pits or blotches, and it may also cause the fruit to drop from the tree before it has fully matured.