Gymnosporangium is a genus of heteroecious plant-pathogenic fungi which alternately infect members of the family Cupressaceae, primarily species in the genus Juniperus (junipers), and members of the family Rosaceae in the subfamily Amygdaloideae. The common name cedar-apple rusts has been used for these fungi. According to the Dictionary of the Fungi, there was 57 species in the genus. In 2023, Species Fungorum lists up to 74 species.
Rusts are fungal plant pathogens of the order Pucciniales causing plant fungal diseases.
Teliospore is the thick-walled resting spore of some fungi, from which the basidium arises.
Gymnosporangium clavipes is a plant pathogen, a fungus that causes cedar-quince rust. Similar to Gymnosporangium juniperi-virginianae and Gymnosporangium globosum, the fungus infects a wide range of Rosaceae, such as apple, hawthorn and quince trees, and also requires an evergreen host such as eastern red cedar or a number of other juniper species to complete its life cycle.
Gymnosporangium globosum is a fungal plant pathogen that causes cedar-hawthorn rust.
Phragmidium violaceum is a plant pathogen native to Europe, Africa, and the Middle East. It primarily infects Rubus species.
Puccinia schedonnardii is a basidiomycete fungus that affects cotton. More commonly known as a “rust,” this pathogen typically affects cotton leaves, which can decrease the quality of the boll at time of harvest. As large percentages of cotton in the United States are resistant to various rust varieties, there is little economic importance to this disease. In places where rust is prevalent, however, growers could see up to a 50% reduction in yield due to rust infection.
Puccinia asparagi is the causative agent of asparagus rust. It is an autoecious fungus, meaning that all stages of its life cycle – pycniospores, aeciospores, and teliospores – all develop upon the same host plant . Rust diseases are among the most destructive plant diseases, known to cause famine following destruction of grains, vegetables, and legumes. Asparagus rust occurs wherever the plant is grown and attacks asparagus plants during and after the cutting season. Asparagus spears are usually harvested before extensive rust symptoms appear. Symptoms are first noticeable on the growing shoots in early summer as light green, oval lesions, followed by tan blister spots and black, protruding blisters later in the season. The lesions are symptoms of Puccinia asparagi during early spring, mid-summer and later summer to fall, respectively. Severe rust infections stunt or kill young asparagus shoots, causing foliage to fall prematurely, and reduce the ability of the plant to store food reserves. The Puccinia asparagi fungus accomplishes this by rust lowering the amounts of root storage metabolites. The infected plant has reduced plant vigor and yield, often leading to death in severe cases. Most rust diseases have several stages, some of which may occur on different hosts; however, in asparagus rust all the life stages occur on asparagus. Because of this, many observers mistake the different stages of the Puccinia asparagi life cycle as the presence of different diseases. The effects of Puccinia asparagi are present worldwide wherever asparagus is being grown. Asparagus rust is a serious threat to the asparagus industry.
Puccinia helianthi is a macrocyclic and autoecious fungal plant pathogen that causes rust on sunflower. It is also known as "common rust" and "red rust" of sunflower.
Uromyces viciae-fabae var. viciae-fabae is a plant pathogen commonly known as faba-bean rust. The rust is distinguished by the typical rust-like marks on the stem and leaves, causing defoliation and loss of photosynthetic surface along with reduction in yield. The disease is fungal and is autoecious meaning it has one plant host. The rust of faba beans is macrocyclic, or contains 5 spores during its life cycle.
Gymnosporangium sabinae is a species of rust fungus in the subdivision Pucciniomycotina. Known as pear rust, European pear rust, or pear trellis rust, it is a heteroecious plant pathogen with Juniperus sabina as the main primary (telial) host and Pyrus communis as the main secondary (aecial) host.
Puccinia horiana is a species of fungus that causes chrysanthemum white rust, is a disease of plant species of the genus Chrysanthemum.
This article summarizes different crops, what common fungal problems they have, and how fungicide should be used in order to mitigate damage and crop loss. This page also covers how specific fungal infections affect crops present in the United States.
Telium, plural telia, are structures produced by rust fungi as part of the reproductive cycle. They are typically yellow or orange drying to brown or black and are exclusively a mechanism for the release of teliospores which are released by wind or water to infect the alternate host in the rust life-cycle. The telial stage provides an overwintering strategy in the life cycle of a parasitic heteroecious fungus by producing teliospores; this occurs on cedar trees. A primary aecial stage is spent parasitizing a separate host plant which is a precursor in the life cycle of heteroecious fungi. Teliospores are released from the telia in the spring. The spores can spread many kilometers through the air, however most are spread near the host plant.
Gymnosporangium clavariiforme is a species of rust fungus which alternately infects Juniperus and hawthorns.
Pine-pine gall rust, also known as western gall rust, is a fungal disease of pine trees. It is caused by Endocronartium harknessii, an autoecious, endocyclic, rust fungus that grows in the vascular cambium of the host. The disease is found on pine trees with two or three needles, such as ponderosa pine, jack pine and scots pine. It is very similar to pine-oak gall rust, but its second host is another Pinus species. The fungal infection results in gall formation on branches or trunks of infected hosts. Gall formation is typically not detrimental to old trees, but has been known to kill younger, less stable saplings. Galls can vary from small growths on branch extremities to grapefruit-sized galls on trunks.
Chrysomyxa weirii, is a fungus that causes a disease, commonly known as Weir's cushion rust, of spruce trees. It is mostly a cosmetic problem, causing yellowish spotting and banding on spruce needles, but in some cases can cause severe premature defoliation. Weir’s cushion rust can also disfigure and reduce growth of spruce trees by targeting the tender needles of newly emerging shoots. This pathogen's spores are spread by wind and water splash and germinate to infect newly developing needles on the same spruce, or neighboring spruce trees. Unlike many other rust disease pathogens, C. weirii is autoecious, only infecting spruce trees. C. weirii is also microcyclic, producing only two of the five possible spore stages common in rust fungi. Trees affected by Weir's cushion rust usually have obvious symptoms, but if treated correctly, the disease can be managed.
Phakopsora euvitis is a rust fungus that causes disease of grape leaves. This rust fungus has been seen in regions including: Eastern Asia, Southern Asia, Southwestern Brazil, the Americas, and northern Australia. It is widely distributed in eastern and southern Asia but was first discovered on grapevines in Darwin, Australia in 2001 and was identified as Asian grapevine leaf rust by July 2007.
Puccinia sorghi, or common rust of maize, is a species of rust fungus that infects corn and species from the plant genus Oxalis.
Cronartium quercuum, also known as pine-oak gall rust is a fungal disease of pine and oak trees. Similar to pine-pine gall rust, this disease is found on pine trees but its second host is an oak tree rather than another pine.
