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dc.contributor.authorSinclair, Bronwyn E.
dc.date.accessioned2012-06-28T01:28:32Z
dc.date.available2012-06-28T01:28:32Z
dc.date.issued1978
dc.identifier.urihttps://hdl.handle.net/10182/4603
dc.description.abstractBotrytis allii is one of several Botrytis species causing diseases of Allium species. It causes the disease known as grey-mould neck rot which is one of the major bulb destroying diseases of the onion crop. It has caused significant losses average 10 per cent in most seasons but under conditions favourable to disease development, bulb losses of 50 per cent or more have been reported by growers. (Maude and Presly, 1977a). Tichelarr (1967) reported similar losses in Holland with averages of 10 to 20 per cent and up to 60 per cent loss of bulbs occurring. Losses caused by B. allii have also been reported in other countries including America and New Zealand. Two other related species may incite a neck rot of onion bulbs and Walker (1926) gave them the distinctive names of mycelial neck rot (B. byssoidea) and small sclerotial neck rot (B. squamosal) in order to differentiate them from grey-mould neck rot (B. allii) . Grey-mould neck rot is the major form of the disease on mature onion bulbs in New Zealadn (Brien et al., 1959) and overseas. Thus neck rot as caused by B. allii has been considered primarily to be a disease of mature bulbs which becomes evident in store, although it has been reported to cause some seedling mortality and some reported to cause some seedling mortality and some reduction of seed set in infected seed crops (Ellerbrock and Lorbeer, 1977). However, losses of bulbs in store are of primary significance because of the high cost of inputs which go into producing and storing each bulb. New Zealand exports mature bulbs and as infected bulbs are not easily identified at the time of harvest, a considerable reduction in the quality of the sample may occur as the disease progresses during transport and storage. Not only will there be a direct loss of bulbs, but the sample may be re-priced because moisture release from rotting bulbs may cause sprouting and a reduction in quality of the sample. Control of the disease has, in the past been difficult and expensive. Prior to 1970, control largely involved the manipulation of post-harvest conditions so as to minimise fungal development in store. However, in 1970, the significance of the fact that the fungus may be seed-borne was realised and the use of benomyl seed-treatments considerably reduced neck rot incidence in store (Maude and Presly, 1977b). The experiments described in this dissertation were designed to investigate the following: (1) The growth of Botrytis spp. In culture (2) The incidence of B. allii in onion seed-lines produced in New Zealand (3) The transmission of B. allii from seed to seedling (4) The testing of a range of selected fungicides for their potential in controlling B. allii.en
dc.language.isoenen
dc.publisherLincoln College, University of Canterburyen
dc.rights.urihttps://researcharchive.lincoln.ac.nz/page/rights
dc.subjectonion seeden
dc.subjectBotrytis speciesen
dc.subjectBotrytis alliien
dc.subjectplant diseasesen
dc.subjectneck roten
dc.subjectseedling mortalityen
dc.subjectdisease controlen
dc.subjectpost-harvest conditionsen
dc.subjectbenomylen
dc.subjectbiological controlen
dc.subjectchemical controlen
dc.subjectfungien
dc.subjectNew Zealanden
dc.titleThe incidence and control of Botrytis spp. on onion seed in New Zealanden
dc.typeDissertationen
thesis.degree.grantorUniversity of Canterburyen
thesis.degree.levelOtheren
thesis.degree.nameBachelor of Horticultural Scienceen
lu.thesis.supervisorGaunt, R. E.
lu.contributor.unitDepartment of Wine, Food and Molecular Biosciencesen
dc.rights.accessRightsDigital thesis can be viewed by current staff and students of Lincoln University only. Print copy available for reading in Lincoln University Library. May be available through inter-library loan.en
dc.subject.anzsrc070308 Crop and Pasture Protection (Pests, Diseases and Weeds)en
dc.subject.anzsrc060704 Plant Pathologyen
dc.subject.anzsrc060505 Mycologyen
dc.subject.anzsrc060504 Microbial Ecologyen


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