THE EFFECT OF TEMPERATURE ON THE TOXICITY OF SEVERAL PESTICIDES TO PHYTOSEIULUS PERSIMILIS (ACARINA: PHYTOSEIIDAE) AND TETRANYCHUS URTICAE (ACARINA: TETRANYCHIDAE)

1981 ◽  
Vol 113 (4) ◽  
pp. 333-336 ◽  
Author(s):  
P. R. Everson ◽  
N. V. Tonks

AbstractThe relationship between posttreatment temperatures of 15°, 20°, 25°, and 30°C and toxicity of six pesticides to adult female Phytoseiulus persimilis Athias-Henriot and Tetranychus urticae Koch were studied in the laboratory.The toxicities of cyhexatin, dicofol, propargite, citrazon, chlorobenzilate, and per-methrin were positively correlated with temperature. Except for propargite and permefhrin, P. persimilis was less susceptible than T. urticae at 15° and 20°C, but equal in susceptibility at 25° and 30°C.The results obtained may indicate a potential value of posttreatment temperature manipulation as a useful adjunct to integrated pest control programs in glasshouses.

1980 ◽  
Vol 112 (1) ◽  
pp. 17-24 ◽  
Author(s):  
P. Everson

AbstractThe activity of the predacious mite Phytoseiulus persimilis Athias-Henriot was greater oh a glass substrate than on a bean leaf substrate. Temperature did not affect its relative activity on the two substrates. The phytophagous mite Tetranychus urticae Koch was inactive on the bean leaf substrate. It was active on the glass substrate and its activity varied with temperature. The functional response of P. persimilis and T. urticae was examined at four temperatures (15°, 20°, 25°, 30 °C). Each functional response to increasing temperature rose curvilinearly to a plateau. From Holling’s disk equation, rate of successful search increased and handling time decreased.


2019 ◽  
Vol 2 (1) ◽  
pp. 37-49
Author(s):  
Wardana Wardana ◽  
Siti Elfira

This research was conducted from July to August 2018 in Wakangka Village, Kapontori Subdistrict, Buton Regency, with the aim of knowing the characteristics of innovation consisting of relative advantages, compatibility, complexity, trialability, and observability and types of innovation decisions in SLPHT rice plants; know the level of adoption of SLPHT farmers for integrated pest control components; know the relationship between the characteristics of innovation consisting of relative advantages, compatibility, complexity, trialability and observability, as well as the type of innovation decisions with the level of SLPHT farmers' adoption of the Integrated Pest Management (IPM) component. The number of respondents was 30 who had attended SLPHT. The data analysis technique used is the analysis of the average and standard deviations and Spearman rank correlation test. To find out the difference in the level of adoption of the IPM components of rice between SLPHT and Non-SLPHT farmers using the t-test. Based on the results of research and discussion, it is found that the characteristics of innovation of farmers provide a relative advantage for farmers, 60% of farmers say there is compatibility of innovation with pest control needs, and 40% of respondents state that innovation is sometimes not according to needs. The adoption rate of SLPHT farmers to the IPM component was 40% of farmers using varieties of lowland rice according to recommendations, 60% using superior rice not in accordance with recommendations. For fertilization, 20% of farmers fertilize according to recommendations, and 80% of farmers fertilize not according to recommendations. For integrated pest control, 50% of farmers conduct IPM, the remaining 50% carry out pest control with certain techniques. For the use of natural enemies, 83.33% of farmers did not utilize natural enemies, the rest, 16.67% did not use natural enemies. For routine observations, 90% of farmers do routine observations but not every week, only 10% of farmers do every week. And observations made are only part of the observation stages. For the wise use of pesticides, all farmers combine pesticides with other techniques. There is a significant relationship between the characteristics of compatibility innovation with the use of natural enemies as indicated by the sig correlation value is 0.05 smaller. There is a significant relationship between complexity with routine observations which is shown by the correlation sig value is 0.013 smaller 0.05. Keywords: Relationship, characteristics, innovation, adoption, IPM, farmers, lowland rice


1979 ◽  
Vol 111 (1) ◽  
pp. 7-10 ◽  
Author(s):  
P. Everson

AbstractThe functional response of the predacious mite Phytoseiulus persimilis Athias-Henriot to increases in the prey density of adult female Tetranychus urticae Koch was examined. Previous studies on artificial substrates have described the functional response curve of P. persimilis to adult female prey as dome-shaped, because as prey density increased the predator was disturbed by prey activity.An experiment to determine the effect of artificial and natural substrates on the activity level of T. urticae was conducted. T. urticae showed a significant increase in activity on artificial substrates of plastic and waterproof paper compared with a substrate of excised bean leaf (Phaseolus vulgaris L.). Since prey activity was significantly influenced by substrate, the functional response of P. persimilis to adult female T. urticae was re-examined. P. persimilis exposed to various densities of T. urticae on excised bean leaf disks (5 cm2) showed a functional response curve having a curvilinear rise to a plateau as prey densities increased from 0.2 to 10.0 prey/cm2.The functional response curve predicted by Holling’s disk equation did not differ significantly from the observed functional response curve.The rate of successful search and the handling time predicted by the disk equation were 0.194 and 10.34 h respectively.


2019 ◽  
Vol 2 (2) ◽  
pp. 88-98
Author(s):  
Wardana Wardana ◽  
Wa Ode Alzarliani ◽  
Muzuna Muzuna

This research was conducted in Wakangka Village, Kapontori Subdistrict, Buton Regency, with the aim of knowing the characteristics of innovation consisting of relative advantages, compatibility, complexity, triability, and observability and types of innovation decisions in SLPHT rice plants; know the level of adoption of SLPHT farmers for integrated pest control components; know the relationship between the characteristics of innovation consisting of relative advantages, compatibility, complexity, triability and observability, as well as the type of innovation decisions with the level of SLPHT farmers' adoption of the Integrated Pest Management (IPM) component. The number of respondents was 30 who had attended SLPHT. The data analysis technique used is the analysis of the average and standard deviations and the spearman rank correlation test. To find out the difference in the level of adoption of the IPM component of rice between SLPHT and Non SLPHT farmers using t-test. Based on the results of research and discussion, it is found that the characteristics of innovation of farmers provide a relative advantage for farmers, 60% of farmers say there is compatibility of innovation with pest control needs, and 40% of respondents state that innovation is sometimes not according to needs. The adoption rate of SLPHT farmers to the IPM component was 40% of farmers using varieties of lowland rice according to recommendations, 60% using superior rice not in accordance with recommendations. For fertilization, 20% of farmers fertilize according to recommendations, and 80% of farmers fertilize not according to recommendations. For integrated pest control, 50% of farmers conduct IPM, the remaining 50% carry out pest control with certain techniques. For the use of natural enemies, 83.33% of farmers did not utilize natural enemies, the rest, 16.67% did not use natural enemies. For routine observations, 90% of farmers do routine observations but not every week, only 10% of farmers do every week. Furthermore, observations made are only part of the observation stages. For the wise use of pesticides, all farmers combine pesticides with other techniques. There was a significant relationship between the characteristics of compatibility innovation with the use of natural enemies as indicated by the sig correlation value is 0.05 smaller. In addition, there was a significant relationship between complexity with routine observations which is shown by the correlation sig value is 0.013 smaller 0.05. Keywords: innovation, adoption, integrated pest control


1970 ◽  
Vol 29 ◽  
pp. 1-8 ◽  
Author(s):  
Md Fazlul Hoque ◽  
Md Wahedul Islam ◽  
M Khalequzzaman

This paper examines the effect of density and temperature on the functional response of adult female Phytoseiulus persimilis to different life stages of the spider mite, Tetranychus urticae. The functional response was determined using functional response assay technique with plant leaf discs an arena. We conducted a logistic regression of the proportion of prey consumed as a function of initial prey density to identify functional response types, and used nonlinear least-squares regression and the random predator equation to estimate attack rates and handling times. In all the cases number of adult male prey attacked by female predator were greater than adult female prey. P. persimilis consumed more eggs and larvae than other stages of prey. Female predator consumed adult prey at each temperature which generally increased with prey density initially but leveled off at higher prey densities. The highest number of eggs, larvae and nymphs consumed by predator in 24 hours was 16.3 ± 0.42, 9.9 ± 0.59 and 9.5 ± 0.40 respectively whereas the highest number of eggs, larvae and nymphs consumed by a single female in 48 hours was 19.5 ± 1.15, 18.6 ± 0.62 and 13.3 ± 0.65 respectively. Handling time generally decreased with temperature whereas successful attack rate increased with temperature except at 30º C. Judging by a/Th values, P. persimilis was most efficient against T. urticae at 30-35ºC, about half as efficient at 25 ºC and performed poorly at 20º C. Again, from a/Th values, P. persimilis was most efficient against T. urticae in egg stage, about half as efficient at larva and nymph stages and performed poorly at adult stage.   Key words: Phytoseiulus persimilis; Tetranychus urticae; functional response; predation; temperature.DOI: http://dx.doi.org/10.3329/ujzru.v29i1.9458 UJZRU 2010; 29(1): 1-8


2018 ◽  
Vol 111 (1) ◽  
pp. 137
Author(s):  
Katarina KOS ◽  
Franci Aco CELAR

The two spotted spider mite, <em>Tetranychus urticae </em><a title="Carl Ludwig Koch" href="https://en.wikipedia.org/wiki/Carl_Ludwig_Koch">C. L. Koch</a>, 1836 is one of the most important pests of greenhouse crops worldwide. Due to its polyphagic range of hosts and rapid development it forms great populations and as such represents a suitable host/prey for lots of natural enemies usable in biological control. Most commonly used predators of Tetranychid mites are predatory mites (<em>Phytoseiulus persimilis </em>Athias-Henriot, 1957, <em>Amblyseius swirskii </em>Athias-Henriot, 1962<em> </em>,…), but among most voracious predators is the larva of a predatory gall midge, <em>Feltiella acarisuga</em> (<a title="Jean Nicolas Vallot" href="https://en.wikipedia.org/wiki/Jean_Nicolas_Vallot">Vallot</a>, 1827) that was found also in greenhouses of the Biotechnical Faculty in Ljubljana on eggplant leaves in 2017. Besides the predatory gall midge also another predator, staphylinid <em>Oligota oviformis </em>Casey, 1893<em> </em>beetles and larvae were found in great numbers. After positive identification of <em>F. acarisuga </em>found naturally in Slovenia, it can be added to the list of indigenous species of natural enemies and thus can be used in biological control programs in greenhouse crop protection against spider mites.


2019 ◽  
Vol 3 (1) ◽  
pp. 1-12
Author(s):  
Wa Ode Dian Purnamasari

This research was conducted from November to December 2018 in Liabuku Village, Bungi Subdistrict, Baubau Town, with the aim of knowing the characteristics of innovation consisting of relative advantages, compatibility, complexity, trialability, and observability and types of innovation decisions in SLPHT rice plants; know the level of adoption of SLPHT farmers for integrated pest control components; know the relationship between the characteristics of innovation consisting of relative advantages, compatibility, complexity, trialability and observability, as well as the type of innovation decisions with the level of SLPHT farmers' adoption of the Integrated Pest Management (IPM) component. The number of respondents was 30 who had attended SLPHT. The data analysis technique used is the analysis of the average and standard deviations and Spearman rank correlation test. To find out the difference in the level of adoption of the IPM components of rice between SLPHT and Non-SLPHT farmers using the t-test. Based on the results of research and discussion, it is found that the characteristics of innovation of farmers provide a relative advantage for farmers, 60% of farmers say there is compatibility of trialability with pest control needs, and 40% of respondents state that innovation is sometimes not according to needs. The adoption rate of SLPHT farmers to the IPM component was 40% of farmers using varieties of lowland rice according to recommendations, 60% using superior rice not in accordance with recommendations. For fertilization, 20% of farmers fertilize according to recommendations, and 80% of farmers fertilize not according to recommendations. For integrated pest control, 50% of farmers conduct IPM, the remaining 50% carry out pest control with certain techniques. For the use of natural enemies, 83.33% of farmers did not utilize natural enemies, the rest, 16.67% did not use natural enemies. For routine observations, 90% of farmers do routine observations but not every week, only 10% of farmers do every week. And observations made are only part of the observation stages. For the wise use of pesticides, all farmers combine pesticides with other techniques. There is a significant relationship between the characteristics of compatibility innovation with the use of natural enemies as indicated by the sig correlation value is 0.05 smaller. There is a significant relationship between complexity with routine observations which is shown by the correlation sig value is 0.013 smaller 0.05.    Keywords: Relationship, characteristics, innovation, adoption, IPM, farmers, lowland rice


Author(s):  
D. T. Gauld ◽  
J. E. G. Raymont

The respiratory rates of three species of planktonic copepods, Acartia clausi, Centropages hamatus and Temora longicornis, were measured at four different temperatures.The relationship between respiratory rate and temperature was found to be similar to that previously found for Calanus, although the slope of the curves differed in the different species.The observations on Centropages at 13 and 170 C. can be divided into two groups and it is suggested that the differences are due to the use of copepods from two different generations.The relationship between the respiratory rates and lengths of Acartia and Centropages agreed very well with that previously found for other species. That for Temora was rather different: the difference is probably due to the distinct difference in the shape of the body of Temora from those of the other species.The application of these measurements to estimates of the food requirements of the copepods is discussed.


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