Cabbage, comprising several cultivars of Brassica oleracea, is a leafy green, red (purple), or white biennial plant grown as an annual vegetable crop for its dense-leaved heads. It is descended from the wild cabbage, and belongs to the "cole crops" or brassicas, meaning it is closely related to broccoli and cauliflower ; Brussels sprouts ; and Savoy cabbage.
Leaf vegetables, also called leafy greens, pot herbs, vegetable greens, or simply greens, are plant leaves eaten as a vegetable, sometimes accompanied by tender petioles and shoots. Leaf vegetables eaten raw in a salad can be called salad greens.
Blackleg, blacklegs or black-legged may refer to:
Grape black rot is a fungal disease caused by an ascomycetous fungus, Guignardia bidwellii, that attacks grape vines during hot and humid weather. “Grape black rot originated in eastern North America, but now occurs in portions of Europe, South America, and Asia. It can cause complete crop loss in warm, humid climates, but is virtually unknown in regions with arid summers.” The name comes from the black fringe that borders growing brown patches on the leaves. The disease also attacks other parts of the plant, “all green parts of the vine: the shoots, leaf and fruit stems, tendrils, and fruit. The most damaging effect is to the fruit”.
Clubroot is a common disease of cabbages, broccoli, cauliflower, Brussels sprouts, radishes, turnips, stocks, wallflowers and other plants of the family Brassicaceae (Cruciferae). It is caused by Plasmodiophora brassicae, which was once considered a slime mold but is now put in the group Phytomyxea. It is the first phytomyxean for which the genome has been sequenced. It has as many as thirteen races. Gall formation or distortion takes place on latent roots and gives the shape of a club or spindle. In the cabbage such attacks on the roots cause undeveloped heads or a failure to head at all, followed often by decline in vigor or by death. It is an important disease, affecting an estimated 10% of the total cultured area worldwide.
Xanthomonas campestris is a gram-negative, obligate aerobic bacterium that is a member of the Xanthomonas genus, which is a group of bacteria that are commonly known for their association with plant disease. This species includes Xanthomonas campestris pv. campestris, the cause of black rot in brassicas, one of the most important diseases of brassicas worldwide.
Rhizoctonia solani is a species of fungus in the order Cantharellales. Basidiocarps are thin, effused, and web-like, but the fungus is more typically encountered in its anamorphic state, as hyphae and sclerotia. The name Rhizoctonia solani is currently applied to a complex of related species that await further research. In its wide sense, Rhizoctonia solani is a facultative plant pathogen with a wide host range and worldwide distribution. It causes various plant diseases such as root rot, damping off, and wire stem. It can also form mycorrhizal associations with orchids.
Erysiphe cruciferarum is a plant pathogen of the family Erysiphaceae, which causes the main powdery mildew of crucifers, including on Brassica crops, such as cauliflower, cabbage, broccoli, and Brussels sprouts. E. cruciferarum is distributed worldwide, and is of particular concentration in continental Europe and the Indian subcontinent. E. cruciferarum is an ascomycete fungus that has both sexual and asexual stages. It is also an obligate parasite that appears to have host specificity; for example, isolates from turnip will not infect Brussels sprout, and vice versa. While being a part of the family Erysiphaceae, it belongs to those members in which the conidia are formed singly and whose haustoria are multilobed.
Napa cabbage is a type of Chinese cabbage originating near the Beijing region of China that is widely used in East Asian cuisine. Since the 20th century, it has also become a widespread crop in Europe, the Americas, and Australia. In much of the world, it is referred to as "Chinese cabbage". In Australia, it is sometimes referred to as "wombok".
Bacterial leaf scorch is a disease state affecting many crops, caused mainly by the xylem-plugging bacterium Xylella fastidiosa. It can be mistaken for ordinary leaf scorch caused by cultural practices such as over-fertilization.
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.
Copper pesticides are copper compounds used as bactericides, algaecides, or fungicides. They can kill bacteria, oomycetes and algae, and prevent fungal spores from germinating. Common forms of fixed copper fungicides include copper sulfate, copper sulfate pentahydrate, copper hydroxide, copper oxychloride sulfate, cuprous oxide, and copper octanoate.
Bagrada hilaris is a species of shield bug known by the common names bagrada bug and painted bug. It could be mistaken for or erroneously referred to as harlequin bug. It is native to southeastern Africa. It is known elsewhere as an introduced species, including California and Arizona, where it was first reported in 2008. It is a major pest insect of Brassica oleracea crops, and related crucifers such as turnips, rape, and mustard. The adult and nymph of the species suck sap from the leaves of the plants, causing wilting, yellowing, and stunting of growth. Besides crucifers, the bugs are known on papaya, sorghum, maize, potato, cotton, caper, pearl millet, and some legumes. Large numbers of the bug congregate on the plants and cause extensive damage.
Black rot, caused by the bacterium Xanthomonas campestris pv. campestris (Xcc), is considered the most important and most destructive disease of crucifers, infecting all cultivated varieties of brassicas worldwide. This disease was first described by botanist and entomologist Harrison Garman in Lexington, Kentucky, US in 1889. Since then, it has been found in nearly every country in which vegetable brassicas are commercially cultivated.
Bacterial soft rots are caused by several types of bacteria, but most commonly by species of gram-negative bacteria, Erwinia, Pectobacterium, and Pseudomonas. It is a destructive disease of fruits, vegetables, and ornamentals found worldwide, and affects genera from nearly all the plant families. The bacteria mainly attack the fleshy storage organs of their hosts, but they also affect succulent buds, stems, and petiole tissues. With the aid of special enzymes, the plant is turned into a liquid mush in order for the bacteria to consume the plant cell's nutrients. Disease spread can be caused by simple physical interaction between infected and healthy tissues during storage or transit. The disease can also be spread by insects. Control of the disease is not always very effective, but sanitary practices in production, storing, and processing are something that can be done in order to slow the spread of the disease and protect yields.
Xanthomonas campestris pv. vesicatoria is a bacterium that causes bacterial leaf spot (BLS) on peppers and tomatoes. It is a gram-negative and rod-shaped. It causes symptoms throughout the above-ground portion of the plant including leaf spots, fruit spots and stem cankers. Since this bacterium cannot live in soil for more than a few weeks and survives as inoculum on plant debris, removal of dead plant material and chemical applications to living plants are considered effective control mechanisms.
Alternaria brassicicola is a fungal necrotrophic plant pathogen that causes black spot disease on a wide range of hosts, particularly in the genus of Brassica, including a number of economically important crops such as cabbage, Chinese cabbage, cauliflower, oilseeds, broccoli and canola. Although mainly known as a significant plant pathogen, it also contributes to various respiratory allergic conditions such as asthma and rhinoconjunctivitis. Despite the presence of mating genes, no sexual reproductive stage has been reported for this fungus. In terms of geography, it is most likely to be found in tropical and sub-tropical regions, but also in places with high rain and humidity such as Poland. It has also been found in Taiwan and Israel. Its main mode of propagation is vegetative. The resulting conidia reside in the soil, air and water. These spores are extremely resilient and can overwinter on crop debris and overwintering herbaceous plants.
Xanthomonas campestris pv. juglandis is an anaerobic, Gram negative, rod-shaped bacteria that can affect walnut trees though the flowers, buds, shoots, branches, trunk, and fruit. It can have devastating effects including premature fruit drop and lesions on the plant. This pathogen was first isolated by Newton B. Pierce in California in 1896 and was then named Pseudomonas juglandis. In 1905 it was reclassified as Bacterium juglandis, in 1930 it became Phytomas juglandis, and in 1939 it was named Xanthomas juglandis. The International Standards for Naming Pathovars declared it to be named Xanthomonas campestris pv. juglandis in 1980. There have been recent proposals to change the name once again to Xanthomonas arboricola pv. juglandis, but this has not yet been universally accepted.
Xanthomonas nasturii a gram-negative, obligate aerobic bacterium that like many other Xanthomonas spp. bacteria has been found associated with plants, in particular watercress. It causes black rot of watercress.
Xanthomonas campestris pv. raphani is a gram-negative, obligate aerobic bacterium that like many other Xanthomonas spp. bacteria has been found associated with plants. This organism is closely related with Xanthomonas campestris pv. campestris, but causes a non-vascular leaf spot disease that is clearly distinct from black rot of brassicas.
