ISSN:0250-8052    

DOI:10.1111/j.1365-2338.1977.tb02402.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

ISSN:0250-8052    

DOI:10.1111/j.1365-2338.1977.tb02403.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractWorld apricot production by no means meets the total need of the international market (fresh and processed fruits) and is far below the potential in view of the existing favourable geographic, climatic and agrotechnical conditions. The cause for this insufficient world production of apricots, particularly in certain countries which have favourable conditions for apricot culture and its expansion, should be investigated using scientific and technical concepts concerning the apricot decline syndrome (apoplexy, sudden wilting, withering of apricots). After the mutual assistance of research workers from different disciplines in investigating this complex disease, the economic security of apricot growing can be improved and apricot decline reduced to an acceptable level. Special attention must be paid to selecting appropriate cultivars, rootstocks or interstocks, locations and cultivation techniques.

ISSN:0250-8052    

DOI:10.1111/j.1365-2338.1977.tb02404.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractPrunusstem pitting disease was first described and recognized as a specific, infectious disease in 1967 and is now known to affect a number ofPrunusspecies. Apricot trees affected by stem pitting show stunted terminal growth and chlorotic, drooping leaves that curl upward and lengthwise. The lower trunk may become enlarged at ground level or below with very thick, spongy bark. Removal of the bark from the affected lower trunk reveals pits and grooves on the woody cylinder. Wood pitting begins below ground, then gradually spreads into the roots and the trunk above ground. Stem pitting is caused by certain strains of the tomato ringspot virus. The causal agent is soil‐borne and also graft transmissible but is not uniformly distributed through infected trees. Naturally infected apricot trees may show a slow decline, or rapid dieback of the terminal growth. The severity of symptoms is determined by the cultivar and the strain of tomato ringspot virus. Control measures forPrunusstem pitting should include: use of propagation material from healthy trees and rogueing of pitted trees in nurseries and orchards. Repeated use of infested nursery sites for stone fruit nurseries should be avoid

ISSN:0250-8052    

DOI:10.1111/j.1365-2338.1977.tb02405.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractApricot chlorotic leaf roll is a graft‐transmissible disease, apparently a mycoplasm infection, which affects Japanese plum and sometimes peach. It is particularly important in Mediterranean areas.First symptoms are a rolling and a yellowing of the leaves, often localized on some twigs. Later, various disorders, often localized on a part of the tree, are observed: proliferation of branched and slender shoots, growth of buds in autumn and winter. Leaf buds break before flower buds.This growth in winter induces sensitivity to frost. Phloem tissues of affected branches are more or less damaged, taking on a brown discolouration. Some branches are destroyed, while on others, new shoots may develop. The presence of weak shoots with small leaves among normal shoots and irregularly distributed dried twigs on the branches is a characteristic aspect of the disease.Symptom expression and evolution of the disease vary much according to environmental conditions, age and rootstock

ISSN:0250-8052    

DOI:10.1111/j.1365-2338.1977.tb02406.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractBacterial canker and dieback (Pseudomonas syringaevan Hall) of apricot is a widespread disease in Europe, except for the Mediterranean areas. Cankers usually develop at pruning wounds or other points of injury. Phloem and cambium become susceptible from just after leaf drop until budding. If the phloem necrosis does not girdle the branch or trunk, cankers develop by the middle or the end of summer. In early summer, the bacterium actually dies out in the infected tissue, and the tree remains resistant during the summer. During this period, the pathogen lives epiphytically on the surface of the leaves, without causing any symptoms. The extent of bacterial necrosis of the phloem depends on the severity of winter frost. Without winter frost, bacterial induced tissue necrosis does not occur. Necrosis is found only if P.syringaehas enough time to proliferate before the onset of frost. The most effective method of control is to carry out spring rather than winter pruning.

ISSN:0250-8052    

DOI:10.1111/j.1365-2338.1977.tb02407.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractCytosporal canker and dieback (Cytospora cinctaSacc.) is a widespread disease in apricot growing areas of Europe, excluding the Mediterranean. The pathogen attacks xylem and phloem. If the necrotic phloem completely girdles the branches or trunk, the section above the girdled region dies. When cambium necrosis does not girdle the branch or trunk, canker development ensues. Apricot trees are susceptible toCytosporainfection between July and the next bud opening.

ISSN:0250-8052    

DOI:10.1111/j.1365-2338.1977.tb02408.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractSimultaneous inoculation withPseudomonas syringaevan Hall andCytospora cinctaSacc. induced more extensive cankers than those caused by either pathogen alone. Freshly cut wounds remained susceptible to cytosporal infection for a longer period than to bacterial inoculation. Knowledge gained of the annual cycle of cytosporal and bacterial diseases offers possibilities for effective control against both pathogens.

ISSN:0250-8052    

DOI:10.1111/j.1365-2338.1977.tb02409.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractEutypacanker and dieback of apricot trees, caused by the ascomycetous fungusEutypa armeniacaeHansf. et Carter, has been recorded in Europe, North America, Australia and South Africa. Samples of diseased sapwood yield the imperfectCytosporinastage in culture, whereas perithecia ofE. armeniacae, immersed in a stroma, develop 2 or more years after death of a branch in high‐rainfall areas. The fungus is a wound parasite. Air‐borne ascospores, disseminated during and after rain, infect xylem tissues which have been freshly exposed by pruning. Cankers develop around the infected wounds; leaves on that part of the branch distal to the canker subsequently wilt and die during summer.E. armeniacaehas been detected on a diverse range of host species, hence elimination of inoculum is not feasible; both biological and chemical approaches to wound protection and ultimate disease control are under investigat

ISSN:0250-8052    

DOI:10.1111/j.1365-2338.1977.tb02410.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractFollowing a brief introduction on the economic importance and reported causes of apricot dieback, the author describes the symptoms, both external and internal, induced byVerticillium dahliaeKleb., the wide host‐range of this fungus, and its diagnostic features on various culture media. Verticillium wilt characteristically affects vigorously growing trees, the latter being most susceptible from 3 to 10 years old. There is either a sudden wilting or a progressive dieback; necrosis is clearly visible and vessels become occluded. Optimum mycelial growth occurs at 22–24°C (range 9–33 °C) and at pH 6.1–6.85 (range 3–3.5–12). Factors affecting growth of the pathogen, particularly the role of ascorbic acid content of fruit trees, are discussed. Epidemiology and control are also reviewed. There are no means for curing diseased trees; breeding offers the best chanc

ISSN:0250-8052    

DOI:10.1111/j.1365-2338.1977.tb02411.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY