twentyfourteen domain was triggered too early. This is usually an indicator for some code in the plugin or theme running too early. Translations should be loaded at the init action or later. Please see Debugging in WordPress for more information. (This message was added in version 6.7.0.) in /var/www/vhosts/gcsar.gov.sy/httpdocs/en/wp-includes/functions.php on line 6131Mageda Mohammed Mofleh Abstract<\/strong><\/p>\n A study on the population dynamics of Tetranychus urticae<\/em> was conducted\u00a0 through two seasons 2007-2008 in\u00a0 the Syrian coastal region. It was found that\u00a0 its activity starts on\u00a0 Ricinus communis<\/em> plants and reaches the highest peak in the first week of May, then the population decreases at the end of May.\u00a0 In June the population rose again, and reaches the peak in July. In middle of August the numbers of T. urticae<\/em> started to decline and disappear in late November in the study region. The activity and numbers of associated predators are dependent on\u00a0 the presence of the prey. Mageda Mohammed Mofleh General Commission for Scientific Agricultural Research- Lattakia Research Center Faculty of Agriculture, Tishreen University 2010 Abstract A study on the population dynamics of Tetranychus urticae was conducted\u00a0 through two seasons 2007-2008 in\u00a0 the Syrian coastal region. It was found that\u00a0 its activity starts on\u00a0 Ricinus communis plants and reaches the highest peak … Continue reading The Efficiency of Some Predators in Biological Control of Tetranychus urticae (Koch) (Acari: Tetranychidae) in Greenhouses<\/span>
\n<\/strong>General Commission for Scientific Agricultural Research-<\/strong>
\n Lattakia Research Center<\/strong>
\nFaculty of Agriculture, Tishreen University<\/strong>
\n 2010<\/strong><\/p>\n
\nMany predators of T. urticae<\/em> were found in the coastal region. The most important host plants were determined for the predators of T. urticae<\/em> in the coastal region, and they were eleven host plants.
\nTemperature plays a key role in the time needed for development of the average fecundity of the spider mite Tetranychus urticae<\/em> and the predator Phytoseiulus persimilis<\/em>. Development time of Tetranychus urticae<\/em> was 10.9\u00b10.59 days at temperature 25\u00b12\u00b0C and 8.15\u00b10.5 days at 30\u00b12\u00b0C. Development time of Phytoseiulus persimilis<\/em> was 6.2 \u00b10.15 and 5.7 \u00b10.3 days under the same temperature, respectively. The average fecundity of P. persimilis<\/em> was 45.2\u00b15.3 and 39.1\u00b14.1 eggs\/female when the predator was fed on eggs, but when P. persimilis<\/em> feed on eggs and immature stages the average fecundity was 52.6\u00b15.9 and 44.8\u00b16.03 eggs\/female on 25\u00b12\u00b0C and 30\u00b12\u00b0C. The average fecundity of T. urticae was 106.5\u00b127.6 and 96.4 \u00b120.5 eggs\\female at the two temperatures, respectively.
\nThe predatory mite Phytoseiulus persimilis<\/em>\u00a0 was able to control the spider mite Tetranychus urticae<\/em> in a greenhouse during 2006-2007 after releasing the predator in rate 1:10 (predator : prey).
\nLife tables studies were conducted on Tetranychus urticae<\/em> and two of its predators (P. persimilis<\/em>, S. gilvifrons<\/em>) at two different temperatures (25 \u00b12 \u00b0C) and (30 \u00b12 \u00b0C). The ages of individuals (x) reached 23 and 18 days for T. urticae<\/em> female, and 22 and 21 days for female of Phytoseiulus persimilis<\/em> on Phaseolus vulgaris<\/em> leaf disk, and 29 and 36 days for female Stethorus gilvifrons<\/em> on two hosts (Ricinus communis<\/em>, eggplant) leaf disks at the two different temperatures respectively.
\nThe total time of development of Stethorus gilvifrons<\/em> immature\u00a0 stages varied significantly according to temperature. Total immature development period on eggplant leaf disk was longest (28.9\u00b10.38 days) at 20 \u00b12 \u00b0C, and shortest (11.84 \u00b10.19days) at 30\u00b12 \u00b0C. The development and survival of the predator affected by host plant of prey . All predator larvae died in the first or second instar when reared on Phaseolus vulgaris<\/em> leaf disk, while eggplant and cucumber were suitable host plants for the development and survival of immature stages of S. gilvifrons<\/em>. The longest development total time (egg, larva, pupa) was on cucumber(31\u00b10.35 days) at 20 \u00b12 \u00b0C, and (28.9\u00b10.38 days) on eggplant at the same temperature with significant differences.
\nThe functional response of S. gilvifrons<\/em> on different density of adult prey was studied in laboratory. The predator consumption increased with increasing prey density, until 57.96 adult\/day when prey density was 100 adult\/ leaf disk. So according Holling (1959) model of functional response , we put\u00a0 S. gilvifrons<\/em> predator under third types (type III).
\nThe T. urticae\u00a0<\/em> gross reproductive rates (GRR) were 143.6 and 120.5 eggs, and the net reproduction rates (R0) was 108.96 and 98.46 eggs and (T,DT) was 10.96 and 1.65day and 8 and 1.2 day at the two different temperatures, respectively. The (GRR) for Phytoseiulus persimilis<\/em>\u00a0 was 48.35 and 42.91 eggs, and (R0) was 44.88 and 39.09 eggs, while (T,DT) was 9.79 and 1.82 day and 10 and 1.87day at the two temperatures, respectively.
\nThe (GRR) for Stethorus gilvifrons<\/em> was 127.46 and 212.5 eggs, and the (R0) was 122.23 and 195.207 eggs, while (T,DT) was 13.03 and 1.88day on Ricinus communis<\/em>\u00a0 and 14.75 and 1.94day on eggplant.
\nThe ability of the predator Stethorus gilvifrons<\/em> Mulsant to control the spider mite Tetranychus urticae<\/em> on eggplant was carried out in a greenhouse during 2007-2008. The best results were obtained in the releases rates 1:5, 1:10, the predator controlled\u00a0 T. urticae<\/em> populations in the sixth week.<\/p>\n","protected":false},"excerpt":{"rendered":"