摘要:

The present paper reviews available studies on the biology, ecology and conTrioxys indicus, a polyphagous endoparasitoid of aphids infesting agricultural crops and vegetables, viz.,Aphis craccivoraandA. gossypii, and presents an up-to-date bibliography. The courtship and mating behaviour, host selection, fecundity, oviposition pattern, development, longevity, sex ratio and density responsiveness behaviour as well as various physico-chemical and biological factors influencing the biology of the parasitoid are described and compared with other aphidiids. Likewise the seasonal history, hyperparasitism, host association and distribution ofT. indicusare also presented. Out of 24 aphid hosts ofT. indicusrecorded, 21 belong to the Aphidinae. Eleven species of hyperparasitoids are recorded. The laboratory culture technique, storage of the mummies at low temperature, release methods and field release ofT. indicusare included in the control efficiency section. The mummy stage of the parasitoid is recommended for release purposes as it can be stored for up to one month at 4°C. Field release studies ofT. indicusreveal that the population of aphids can be checked by the parasitoid's introduction. The list of references constitutes a bibliography of most of the relevant papers citing the biology, ecology and control efficiency of the aphidiid parasitoids of the world.

ISSN:0144-8765    

DOI:10.1080/01448765.1992.9754606

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

As an element of biological disease and pest management, field trials with species mixtures of cereals were carried out from 1983–1989. Mixtures of winter-rye/winter-wheat (food grains) and spring-barley/oats (feeding grains) were tested for their ability to reduce fungal leaf damage. Significant and regular reductions in disease frequency and intensity were achieved. This was especially true forErysiphe graminisf.sp.hordeiandPuccinia reconditaf.sp.tritici, but also included leaf spot diseases caused byDrechslera avenaeandRhynchosporium secalis.Compared with fungicide applications, mixtures of two species showed adequate effects in reducing disease intensity. Harvesting of mixtures never presented a problem. This was especially due to a conspicuous maturity adjustment. Species mixtures of cereals therefore deserve more attention in environmentally safe cropping systems.

ISSN:0144-8765    

DOI:10.1080/01448765.1992.9754607

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

In biological agriculture and horticulture diluted extracts of seaweed are applied to promote growth, prevent pests and diseases and improve the quality of the products. The efficacy of the extracts is probably based upon plant hormones (mainly cytokinins) and trace nutrients present in the extracts. A survey of the recent literature is given concerning the properties of seaweed extracts, methods of application, their effects and putative working mechanisms. The significance of seaweed extracts in biological agriculture and horticulture is evaluated, regarding environmental aspects of production and use.

ISSN:0144-8765    

DOI:10.1080/01448765.1992.9754608

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Biologically and conventionally grown products of the same variety, obtained from neighbouring farms were compared for their influence on the fertility of two groups of laboratory rats up to the third generation. Group A was fed with biologically cultivated food and group B with conventionally cultivated food. This investigation included a comprehensive analytica programme. Any nutritional deficiencies were compensated for so that, according to analytical standards, the diets were of equal nutritional quality.

ISSN:0144-8765    

DOI:10.1080/01448765.1992.9754609

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

ISSN:0144-8765    

DOI:10.1080/01448765.1992.9754610

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

ISSN:0144-8765    

DOI:10.1080/01448765.1992.9754611

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

ISSN:0144-8765    

DOI:10.1080/01448765.1992.9754612

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

ISSN:0144-8765    

DOI:10.1080/01448765.1992.9754613

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

ISSN:0144-8765    

DOI:10.1080/01448765.1992.9754605

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor