摘要:

A field trial was carried out at a number of sites in Cairo to determine the effectiveness of permethrin as an outdoor ultra low volume aerosol against houseflies. A Leco HD u.I.v. unit was used to deliver 5 g and 10 g pyrethroid in 500 ml diesel oil per hectare. Approximately 99% control was achieved with treatments on alternate days.

ISSN:0309-7943    

DOI:10.1080/09670877909414357

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

The insect pest problems of agriculture in Bangladesh have not been adequately studied or surveyed. Nevertheless some preliminary data are available to indicate the possible seasonal and annual abundance of the most important pests attacking rice, sugarcane and jute.

ISSN:0309-7943    

DOI:10.1080/09670877909414358

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

As a result of the failure of four leaf-cutting ant control schemes in Paraguay since 1961, a set of principles on which a fifth scheme was based are given. Some simple locally developed and manufactured toxic baits are described which it is thought are more suitable for poor and developing countries than some of the preceeding more sophisticated, complex or costly schemes. Examples from other countries are quoted of a complex scheme that failed and a simple scheme that is now in operation. It is suggested that the principles of the current Paraguayan scheme and the toxic baits developed for it may have wider application where leaf-cutting ants are a problem.

ISSN:0309-7943    

DOI:10.1080/09670877909414359

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Sorghum can be heavily damaged by birds in Botswana but as control measures are expensive bird-proof sorghums merit consideration. However, varietal resistance is difficult to evaluate because when many varieties are grown close together birds avoid unpalatable ones, thus giving a false estimate of resistance. This paper describes the performance of a supposedly resistant variety, Savannah 5, when grown in time isolation from other sorghums. Heavy grain losses resulted, mainly due to doves (Columbidae) and weavers (Ploceidae). Consequently it is suggested that all resistant cultivars be tested in isolation before final release to farmers.

ISSN:0309-7943    

DOI:10.1080/09670877909414360

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Evidence for the possible development of groundnut (Arachis hypogaeaL.) cultivars with favourable agronomic characteristics and resistance to aflatoxinproducing strains ofAspergillusspecies is presented. In studies of F2and F3progenies from crosses of resistant and susceptible genotypes data on the frequency distribution and least square estimates of genetic effects showed the possibility of selecting for resistance to seed colonisation by the fungus. Yield, value and seed quality data for seven advanced lines developed by using pedigree selection from crosses showed that potential favourable groundnut cultivars may be developed.

ISSN:0309-7943    

DOI:10.1080/09670877909414361

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Fungal and bacterial flora of cowpea seeds in northern Nigeria were studied in agar plates and in plates containing moistened filter paper. Seeds were surface-sterilised with either sodium hypochlorite solution or mercuric chloride solution. About 90 fungal species, the vast majority of which were non-pathogens, were detected on seeds obtained from markets and from fields affected by various diseases. Cowpea pathogens detected on seeds from markets includedAscochytasp.,Colletotrichum lindemuthianum. C. truncatum, Rhizoctonia solani (Thanatephorus cucumeris), Fusarium oxysporum, F. solani, Macrophomina phaseolina, Septoria vignaeandCorticium rolfsii. Except forAscochytasp.,C. lindemuthianumandFusarium oxysporum, all the above fungi were isolated from seeds from field plots which also yielded three other pathogens, namelyColletotrichum capsici, Cercospora canescensandXanthomonas vignicola. Seed-plant transmission was established for all pathogens, exceptC. canescens, detected on seeds from the field plots.

ISSN:0309-7943    

DOI:10.1080/09670877909414362

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

V.I.v. captafol spray treatments applied using a 1.8m swath (3.3 kg a.i./ha/application) were more effective than treatments using a 3.6 m swath (1.67 kg a.i./ha/application). At sites with more than 700 mm rainfall during the crop's field life weekly applications were more effective than spraying at 10- and 14-day intervals, but at the drier sites (< 650 mm rainfall) spraying at 10 days was adequate.

ISSN:0309-7943    

DOI:10.1080/09670877909414363

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Work on nematode parasites of citrus in India from 1956 to 1977 is reviewed and discussed. Seventy species within 37 genera of plant parasitic nematodes in association with citrus roots have been reported from India. Work on four nematode species,Tylenchulus semipenetrans, Pratylenchus coffeae, Hoplolalmus indicusandMeloidogynesp., for which proof of pathogenicity to citrus is available is reviewed. An up-to-date annotated list of parasitic nematodes associated with citrus roots is presented. Future lines of work on nematode parasites of citrus in India are discussed.

ISSN:0309-7943    

DOI:10.1080/09670877909414364

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

In field experiments conducted at the Nyankpala Agricultural Station, Ghana, during 1976–77, soil moisture conditions appeared to be the deciding factor in determining the frequency of handweeding needed to obtain maximum seed cotton yields. In 1976, when planting was early and the late, heavy rains in October prolonged weed growth, two handweedings at 4 and 8 weeks after seeding (w.a.s.) gave comparable yields to continuous weeding and significantly better yields than an alachlor + fluometuron herbicide mixture. Supplementary weeding did not enhance the mixture's performance.

ISSN:0309-7943    

DOI:10.1080/09670877909414365

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Three wild oat herbicides benzoylprop-ethyl, flamprop-isopropyl and flamprop-methyl were each applied in mixtures with the chlorophenoxy herbicides 2,4-D, dichlorprop, MCPA and mecoprop. The effect of the mixtures on Maris Dove oats was studied. All mixtures induced significantly less suppression of growth in oats than that induced by the wild oat herbicides alone at the lower rates. This effect demonstrated the existence of antagonism between the three wild oat herbicides and the four chlorophenoxy compounds tested. Antagonism was inversely related to the amount of wild oat herbicide present in the mixture.

ISSN:0309-7943    

DOI:10.1080/09670877909414366

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor