Temperature Effects on the Susceptibility of the Colorado Potato Beetle (Coleoptera: Chrysomelidae) to Beauveria bassiana (Balsamo) Vuillemin in Poland, the Czech Republic and the United States2

2000 ◽  
Vol 35 (3) ◽  
pp. 251-258 ◽  
Author(s):  
Phyllis A. W. Martin ◽  
Robert F. W. Schroder ◽  
Tadeusz J. Poprawski ◽  
Jerzy J. Lipa ◽  
Ervin Hausvater ◽  
...  

Beauveria bassiana (Balsamo) Vuillemin is a fungus with broad spectrum insecticidal activity. As a biological control agent used against Colorado potato beetles (Leptinotarsa decemlineata (Say)), this fungus has performed erratically in various field studies. This inconsistent performance has been attributed to formulation problems, UV sensitivity, and humidity. In a multi-site test, B. bassiana controlled Colorado potato beetle larvae in both Poland and the Czech Republic, but not in Maryland. Control was measured by reduction in populations of beetle larvae. One of the major differences among these sites was temperature. In Poland, the mean temperature ranged from 5°C to 23°C; in the Czech Republic the average temperature ranged from 6.7°C to 18.7°C; and in Maryland, temperatures at time of application exceeded 45°C at canopy level. This led us to examine B. bassiana growth in vitro.While B. bassiana grew in the laboratory from 16 to 30°C, the B. bassiana from a formulated product (Mycotrol™, Mycotech, Butte, MT) did not germinate at temperatures above 37°C. Germination and subsequent development of this entomopathogenic fungi are critical factors in the infection and control of the Colorado potato beetle. As a consequence of the inability to germinate at high temperatures, B. bassiana would not be expected to effectively control pest insects in climates with hot summers. This fungus, however, may be suitable for insect control in early spring or in cool temperature climates during the growing season.

Insects ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1077
Author(s):  
Rostislav Zemek ◽  
Jana Konopická ◽  
Eva Jozová ◽  
Oxana Skoková Habuštová

The Colorado potato beetle, Leptinotarsa decemlineata (Say), is a serious, widely distributed pest of potato and other crops. This pest is able to defoliate the host plant and cause severe yield loss. Moreover, the pest quickly becomes resistant to many chemical pesticides. Therefore, the development of novel biopesticides targeting this pest is urgently needed. The purpose of this study was to obtain new strains of the entomopathogenic fungus Beauveria bassiana and assess their efficacy against L. decemlineata adults under laboratory conditions. Twelve strains were isolated from cadavers of Colorado potato beetles collected in potato fields in the Czech Republic. Test beetles were treated by suspensions of conidia at the concentration of 1 × 107 spores per milliliter and their survival was recorded daily for three weeks. The results of the bioassays revealed that all new native strains were pathogenic to L. decemlineata adults and caused mortality up to 100% at the end of the trial period with an LT50 of about 7 days. These strains were more virulent than a reference strain GHA and some of them can be recommended for the development of a new mycoinsecticide against L. decemlineata. Our findings also highlight the importance of searching for perspective strains of entomopathogenic fungi among naturally infected hosts.


Author(s):  
Eva Kocmánková ◽  
Miroslav Trnka ◽  
Daniela Semerádová ◽  
Zdeněk Žalud ◽  
Martin Dubrovský ◽  
...  

This present study is focused on the modeling of the most important potato pest i.e Colorado potato beetle (Leptinotarsa decemlineata, Say 1824) development in relation to the climate conditions over the area of the Czech Republic. The aim was to develop a model allowing the assessment of the CPB possible spread under the climate change. For the estimation of the CPB occurrence in expected climate conditions we used a dynamic model CLIMEX that enables to determine the suitability of a given location climate for the pests survival and infestation capability based on known pests requirements to the climate conditions. Following the validation and calibration of the model outputs, the meteorological data were altered according to three Global Circulation Models (ECHAM4, HadCM3, NCARPCM) that were driven by two SRES emission scenarios (A2, B1) with two assumed levels of climate system sensitivity for period 2025 and 2050. Model output, for current and expected climate conditions, were visualized by GIS using a digital landscape model. Under all climate change scenarios we noted a widening of CPB distribution area and change in the infestation pressure of the pest.


2012 ◽  
Vol 29 (No. 3) ◽  
pp. 85-91 ◽  
Author(s):  
V. Blažek ◽  
V. Falta ◽  
R. Vávra ◽  
V. Beneš

: In the Czech Republic, there is still a predominance of obsolete apple orchards that were established more than 15 years ago and that are not profitable under contemporary conditions. Typical features of these orchards are low or medium tree densities, freely growing semi-standard trees or hedgerows on semi-dwarf, or sometimes also on vigorous, rootstocks. The farmers are not always in a position to completely renovate them, and therefore they are interested in their topworking. The present paper studied the effectiveness of this measure under the current economic and market conditions of this country, using 3 types of orchards with different spacings and rootstocks and 5 groups of tree densities. Four cultivars were chosen as examples of different starting statuses for the modelling of subsequent development in three time horizons and for the prediction of profitability of this treatment. The profitability is based on an increase in farmer prices for cultivars that are presently recommended for replacement of the older ones according to the recent development of these prices on the fresh market. In the case of topworking for Spartan cv., an economic return of the measure can be expected at the earliest after 8 years of running the treated orchard. The greatest increase in profit can be achieved in orchards on the rootstock M 9. Nevertheless, with the decline of tree numbers in the orchard, or with the increase in tree losses, the general economic effectiveness of topworking notably falls. In the case of trees on the rootstock MM 106, this measure can have an economic effect only if at least 80% of the trees is in a good health state and it is presumed that the orchard will be used for another 10 years at least. A list of recommended cultivars to be used for replacement of the old ones is given.


Author(s):  
Endang Sulistyowati ◽  
Febrilia Nur AINI

Beauveria bassiana is one of the entomopathogen fungi which is known as biological control agent of cocoa pod borer and cocoa mirids (Helopeltis spp.). Because of its effectiveness in the fields is still not consistent, so we conduct a research with the objective to know the possibility of Beauveria bassiana to be established as a endophyte. Various fungal entomopathogens have already been reported as endophytes and the various methods used to inoculate the plants with B. bassiana were partially effective. The research has been conducted in laboratory of Plant Protection, Indonesian Coffee and Cocoa Research Institute by inoculating of cocoa seeds and cocoa nursery with B. bassiana suspension.  The trial was arranged  by randomized complete block design with a factorial arrangement. The factor were spore concentration of B. bassiana (0; 2; and 4 g/ 10 l) and cocoa varieties (family of ICS 60, TSH858, and hybrid). The trial were use  four replications. The results showed that the fungal entomopathogen B. bassiana was established as an endophyte in cocoa seedling, both from cocoa seeds and nursery application. Percentage of existence of B. bassiana colonies as endophytes one month after seeds application were ICS 60 amounted to 93.3 % both on concentration treatments, while the families of TSH 858 by 80 % and 86.67 % respectively in 2 g and 4 g per 10 l of B. bassiana spores concentration treament.. The lowest percentage was in hybrids, which amounted to 66.67% and 50%. B. bassiana colonies was exixtence as an endophyte in culture from root, stem and leaves of cocoa seedling up to 5 months post inoculation. While the application on nursery by soil drenshing, leaf spraying, and stem injection , it was known that B. bassiana colonies were found in the tissues of leaves, stems, and roots until two months after application. Colonies of B. bassiana as endophytes still exsist until six weeks after nursery was planted in the field. 


Author(s):  
T. V. Andrianova

Abstract A description is provided for Stagonospora atriplicis, a potential biological control agent of Atriplex and Chenopodium weeds. Information is included on the disease caused by the organism, its transmission, geographical distribution (Kenya, South Africa, Zimbabwe, Canada, USA, Colombia, Cyprus, Georgia, Kyrgyzstan, Russia, Australia, New Zealand, Austria, Belgium, Bulgaria, Czech Republic, Estonia, France, Germany, UK, Hungary, Italy, Latvia, Romania, Sweden, Ukraine and Hawaii) and hosts (Allenrolfea occidentalis, Atriplex spp., Chenopodium spp. and Syzygium guineense).


Author(s):  
Ines Borgi ◽  
Jean-William Dupuy ◽  
Imen Blibech ◽  
Delphine Lapaillerie ◽  
Anne-Marie Lomenech ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document