Although bigvein virus stays in the land once it is introduced in the soil, all is not lost. Lettuce diseases and pests, description, uses, propagation. Even though the virus is soilborne and therefore always present in infested fields, disease severity may vary greatly from season to season. If you desire to recieve a personal copy with price information. It has caused economically significant losses in new zealand, particularly in crops. If it isnt the slugs or other insects devouring the tender leaves, its a disease like lettuce big vein virus. Occurrence and partial characterization of lettuce big. Lettuce bigvein disease causes leaf distortion and ruffling in affected lettuce plants. The leaves stiffen and the veins turn a light colour and become more pronounced. Symptoms vary according to type or variety of lettuce. Big vein is an economically damaging disease of lettuce lactuca sativa caused by the olpidium brassicaevectored mirafiori lettuce bigvein virus mlbvv. The virus is not transmissible by inoculation of sap but has been transmitted by whitefly inoculation to plants in at least 45 species and 15 families duffus et al.
Read comparison of the coat protein genes of lettuce big vein associated virus isolates from australia with those of isolates from other continents, archives of virology on deepdyve, the. So far no lettuce cultivars have been identified that express a high level of resistance that does not vary as the severity of the disease. The emerging lettuce bigvein disease lbvd is causing losses in lettuce production ranging from 30 to 70% worldwide. Identification of mirafiori lettuce bigvein virus and. Both mirafiori lettuce big vein virus mlbvv and lettuce big vein associate virus lbvav are associated with big vein infected lettuce plants, but only mlbvv has been identified as a causal agent. Characterization of lettuce bigvein associated virus and. Big vein bv is an economically damaging disease of lettuce lactuca sativa l. Lettuce bigvein associated virus lbvav is a pathogenic plant virus. Full text of diseases of lettuce see other formats i 1 division of agricultural sciences university of california california agricultural experiment station extension service circular 448. We used illumina small rna sequencing srnaseq to identify viruses present in symptomatic lettuce plants. Transfer resistance from cultivar pavane into iceberg type breeding lines, continued greenhouse and field tests.
General information about lettuce bigvein associated varicosavirus lbvv00. Lettuce big vein agent lbva is probably caused by a virus. Viruses are a major cause of loss in many australian vegetable crops. Bigvein disease bv of lettuce has been attributed to infection by lettuce bigvein virus lbvv, vectored by the soil fungus olpidium brassicae. Virus diseases of lettuce in brazil global science books. Small rnaseq to characterize viruses responsible of.
Lettuce big vein virus lettuce bigvein lbv, is a viral disease which is transmitted from plant to plant by the soilborne fungus olpidium brassicae. This disease was first associated in 1983 with a rodshaped virus named lettuce bigvein associated virus lbvav, which is transmitted by the obligately parasitic soilinhabiting fungus, olpidium brassicae. Common symptoms of lbv include ruffled or malformed. Mirafiori lettuce bigvein virus mlbvv formerly known as mirafiori lettuce virus has been recently identified as a causal agent of big vein while lettuce bigvein associated virus lbvav formerly known as lettuce bigvein virus, previously thought to cause big vein, is yet to be confirmed as a causal agent. Plant disease february 2006 233 host resistance to mirafiori lettuce bigvein virus and lettuce bigvein associated virus and virus sequence diversity and frequency in california ryan j.
Two viruses are associated with lbvd, lettuce bigvein associated virus lbvav. However, lettuce bigvein disease, although long thought to be induced by a virus previously designated lettuce bigvein virus, is now considered to be caused by isolates of the species mirafiori lettuce big. Lettuce bigvein associated varicosavirus wikispecies. How to deal with bigvein virus and tipburn in lettuce. A, particles of lettuce bigvein virus isolate br8 from crude sap of lettuce infected by mechanical inoculation. Lettuce bigvein disease bvd affects all major lettuceproducing areas of the world. Lettuce necrotic yellow virus how is lettuce necrotic. The reported variation in the reaction of wild lactuca species to pathogens and pests is summarized, including viral pathogens e.
This causal agent may be a virus but has not been characterized 12,20. Resistance of wild lactuca genetic resources to diseases. The causal agent is mirafiori lettuce bigvein virus mlbvv, an ophiovirus transmitted by the soilborne. Mirafiori lettuce big vein virus milbvv and lettuce big vein associated virus lbvav were found in association with big vein disease of lettuce in iran. Several studies have associated this disease with mirafiori lettuce big vein virus milbvv alone or in mixed infection with lettuce big vein associated virus lbvav.
Lettuce bigvein disease is a disease thats been the subject of some controversy in the scientific community in recent years. Lettuce bigvein disease causes leaf distortion and ruffling in affected lettuce plants this disease was first associated in 1983 with a rodshaped virus named lettuce bigvein associated virus lbvav. New dna equipment reveals risk of socalled symptomfree. Abstract california lettuce research board for the. These symptoms resemble those caused by lettuce bigvein disease lbvd, an important disease of lettuce worldwide. The occurrence of big vein disease symptoms and the association of lettuce bigvein associated virus lbvav and mirafiori lettuce bigvein virus mlbvv was evaluated by rtpcr using specific.
Common symptoms of lbv include ruffled or malformed leaves with enlarged clear veins. Lettuce big vein virus lbvv is a plant pathogenic virus. Pdf further evidence of mirafiori lettuce bigvein virus. For several decades, it was believed to be caused by the lettuce bigvein associated virus lbvav. The worst affected plants are often stunted and rarely. Lettuce mosaic virus ndash lmv, mirafiori lettuce viruslettuce big. Lettuce bigvein disease lbvd is a common chytrid and soilborne virus disease that affects lettuce in western australia. Although big vein is a perennial problem in the united states, the extent of mlbvv and lbvav infection and diversity is unknown. Lettuce bigvein associated virus lbvav is also frequently identified in symptomatic plants, but no causal relationship has been demonstrated.
The virus is seedborne and overwinters in wild hosts and weeds. The emerging lettuce big vein disease lbvd is causing losses in lettuce production ranging from 30 to 70% worldwide. Citrus psorosis and mirafiori lettuce bigvein ophiovirus. First reports of lettuce bigvein associated virus and. Studies on lettuce big vein disease university of auckland. Page 4 of 9 the genus varicosavirus is recognized by the ictv, but has not yet been assigned to a family. Lettuce big vein is an important disease of lettuce lactuca sativa l. Botanical, mycological, zoological, and prokaryotic species names follow the linnaean format, consisting of an italicized latinized binomen with a capitalized genus name and a.
Genetic variation for bigvein symptom expression and. Phylogenetic analysis of the viral polymerase gene consistently places the genus with its type species. Mirafiori lettuce virus milv and lettuce big vein virus lbvv sequence diversity and frequency in california and arizona lettuce, and analysis. Lettuce growers usually plant in rotation, so that infected lands can be planted to another crop in spring and used for lettuce in warm conditions, when the disease will not occur. The virus that causes big vein is soilborne and is introduced into lettuce plants by a soil fungus olpidium brassicae that attaches itself to lettuce roots. Occurrence of mirafiore lettuce virus and lettuce bigvein virus. The lettuce plant can grow to a height of 30100 cm 1240 in in height and is typically grown as an annual, harvested after only one growing season. Possibility and challenges of conversion of current virus. Available resistance can be described as resistance against big vein. Several studies have associated this disease with mirafiori lettuce bigvein virus. Several studies have associated this disease with mirafiori lettuce. Citrus psorosis cpsv and mirafiori lettuce bigvein virus milbvv belong to the family ophioviridae, plant viruses with filamentous nucleocapsids and segmented genomes of negative polarity, causing.
It causes chlorophyll clearing of the veins of the lettuce leaf, leaf crinkling and. Read citrus psorosis and mirafiori lettuce bigvein ophiovirus coat proteins localize to the cytoplasm and self interact in vivo, virus research on deepdyve, the largest online rental service for. Detection of varicosavirus and ophiovirus in lettuce. Insecticidal sprays would presumably help to delay the spread of this particular virus disease. Maisonneuve high level resistance to mirafiori lettuce bigvein virus, the causal agent of big vein disease, is known in l. Detection of varicosavirus and ophiovirus in lettuce associated with lettuce bigvein symptoms in brazil. Lbvv is defined as lettuce bigvein virus somewhat frequently. Leaves can be smooth or curly and are usually green or red in color. Lettuce may be referred to as garden lettuce and is believed to originate from asia minor and the middle east. It is certain, however, that this viral disease is transmitted by an oomycete, olpidium virulentus, previously known as o. Lettuce isnt difficult to grow, but it sure does seem to have its share of issues. Comparison of the coat protein genes of lettuce big vein. Maccarone ld 2009 molecular genetic characterization of mirafiori lettuce bigvein virus and lettuce bigvein associated virus and their vector olpidiumvirulentus associated with lettuce big.
Host resistance to mirafiori lettuce bigvein virus and. Occurrence of mirafiori lettuce virus and lettuce bigvein. Hayes et al pathogen responsible mirafiori lettuce virus. Discoveries in the last years have shown that it is in fact caused by the mirafiori lettuce virus milv.
Infected seed is the most common source of infection. Molecular genetic characterisation of mirafiori lettuce. Lettuce lactuca sativabig vein pacific northwest pest. Big vein is more prevalent and severe during cool spring weather.