摘要:

AbstractHealing cankers were obtained in some artificial inoculation tests with combination of four hypovirulent strains ofCryphonectria parasiticawhich sporulated on the cankers.

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1991.tb00945.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

AbstractLarge scaleP. radiatamonoculture has been in existence in New Zealand for over 60 years. During this time a number of damaging diseases (e. g.Sirex‐Amylostereum, Dothistroma, Armillaria, Cydaneusmaneedle cast.Sphaeropsisdie‐back etc.) have occurred but the impact was by no means devastating as these diseases are either controllable or in some the losses were deemed acceptable. As a large proportion of the biomass produced before age 10–12 is waste‐thinned, the acceptable level of disease loss is thereby very high. The practice of clear felling and short rotation reduces some of the disease risks common in other forest systems. Outlook for future disease threat is discussed with respect to current trends toward clonal forestry and the possible arrival of additional exotic pa

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1991.tb00946.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

AbstractVolatile terpenes increase in xylem tissue after infection ofPinus thunbergiiwith the pine wood nematode (Bursaphelenchus xylophilus). The role of these terpenes in traeheid cavitation, which blocks xylem‐sap ascent and leads to water deficit in pine trees, was assessed. Volatile terpene concentration increased long before initiation of tracheid cavitation. After the volatile terpenes reached the highest concentration, severe cavitation developed. Direct injection of α‐pinene into healthy pine trunks formed artificial cavitation in xylem. These observations support the hypothesis that excessively produced volatiles, which are hydrophobic and have lower surface tension than water can promote tracheid cavitation in pine wilt dis

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1991.tb00947.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

AbstractMycoplasma‐like organisms (MLOs) were detected in almost all examined trees ofAlnus glutinosaandA. incanaolder than approximately 5 years. The minority of trees showed symptoms of decline while the others appeared healthy. MLOs were also found inA. glutinosavar.barbata, A. hirsuta, A. rubra, A. rugosa, A. subcordata, andA. tenuifoli

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1991.tb00948.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

AbstractDamping‐off caused byFusarium oxysporumSchlecht inPinus banksianaLamb, was reduced significantly when inoculated with an ectomycorrhizal fungus,Laccaria laccata(Scop. ex Fr.) Berk. and Br. In paired culture, growth ofF. oxysporumwas significantly reduced byL. laccata. The number of colony forming units ofF. oxysporumwas reduced significantly in the rhizosphere ofP. banksianaseedlings when inoculated withL. laccata. Spore germination and germ tube length ofF. oxysporumwas inhibited strongly by culture filtrate ofL. laccataand root exudate ofP. banksianainoculated withL. laccata. Mycorrhizal seedlings had significantly higher amount of total soluble phenols than nonmycorrhizal one

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1991.tb00949.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

AbstractYoung spruce trees [Picea abies(L.) Karst.] artificially inoculated withRhizosphaera kalkhoffiiB. andLophodermium piceae(F.) v. H. were exposed to fumigations with O3and SO2and drought. These treatments showed no influence on the infection‐rates of the fungi.R. kalkhoffiiproved to be a saprophyte living for a long period as an epiphyte on the needle surface

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1991.tb00950.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

AbstractA new species,Pseudocercospora kaiseri, causing leaf spot ofErythrina strictaRoxb. from India is described and illustrated.

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1991.tb00951.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY