Development Of Two-spotted Spider Mite Research Articles

Preference and performance of the two-spotted spider mite Tetranychus urticae (Acari: Tetranychidae) on strawberry cultivars.

The two-spotted spider mite (TSSM), Tetranychus urticae Koch (Acari: Tetranychidae), is one of the most serious pests of strawberry worldwide. Understanding the preference of TSSM for particular cultivars of strawberry and performance on them helps identify host-plant resistance to this pest mite. In this study, we tested preference, developmental duration, fecundity and population levels of TSSM on 14 strawberry cultivars. TSSM showed strong preference for the Chinese cultivars of Yanxiang, Baixuegongzhu, and Jingtaoxiang. Development of TSSM on the cultivars varied from 32.32 to 36.82days; it was longest on the cultivars Hongxiutianxiang and Baixuegongzhu, and shortest on Yanxiang, Jingzangxiang, and Darselect as well as on a wild variety (Wuye). TSSM had high fecundity on the cultivars Yanxiang, Taoxun, Hongxiutianxiang, Jingzangxiang, Albion and Baixuegongzhu as well as on Wuye, whereas egg production was lowest on Sweet Charlie, Portola, Akihime, and Benihoppe. After 28days of plant infestation with 10 pairs of adults, the cultivars Yanxiang, Taoxun, Jingzangxiang, Jingtaoxiang, and Baixuegongzhu had the highest number of mites (> 1000 per plant), whereas mite numbers on Albion and Camarosa were low. The population size of TSSM was correlated with fecundity, but no correlation was found between other preference/performance measures. Our study suggests that a rapid increase of population size of TSSM on cultivars of strawberry is related to high fecundity, and also that there are substantial differences in preference and performance across cultivars.

Development of two-spotted spider mite, Tetranychus urticae koch, at different temperatures

Development of two-spotted spider mite, <i>Tetranychus urticae</i> koch, at different temperatures

BIOLOGICAL STUDY OF TWO SPOTTED SPIDER MITE Tetranychus sp. (ACARI: TETRANYCHIDAE) ON THREE LEAF PHASES OF MUNG BEAN AND ADZUKI BEAN FOR MITE MASS REARING

Two-spotted spider mite (TSM) Tetranychus sp. is one of prey mites for phyotoseiid mite mass rearing. Based on previous research that TSM population developed well on Mung bean ( V igna radiata ) and Adzuki bean ( V . angularis ) as host plants, confirmed growth and development of TSM on both beans. Research was aimed to observe biology of TSM on three phases of Mung bean and Adzuki bean leaf such as at primary leaf unrolled completely (V1), at the 1 st trifoliate unrolled completely (V2), and at the 2 nd trifoliate unrolled completely (V3). Pre adult stadia, life cycle, male and female longevity, female fecundity of TSM, and trichome density were observed on petri dishes contained each leaf phase of beans. Result showed that three leaf phases of beans did not influence significantly in all biological variables, except fecundity. TSM fecundity was the highest on V3 phase of Mung bean (86.90). Trichome density on Mung bean leaf surface per mm² was lower than Adzuki bean. Trichome density of upper leaf surface of V3 phase of Mung bean (10.53) and Adzuki bean (3.07) were lower than V1 (13.20; 12.40) and V2 phase (6.20; 5.27). V3 phase of Mung bean was most suitable for TSM mass rearing. Key words: fecundity, leaf phase, mass rearing, trichome density, two-spotted spider mite

Comparative biology and fertility life tables of Tetranychus urticae Koch (Acari: Tetranychidae) on different common bean cultivars

The quality of the host plant affects the development and survival of two-spotted spider mite (TSSM) Tetranychus urticae Koch. The biology and fertility life tables of T. urticae on six cultivars of common bean (Phaseolus vulgaris L.) (chiti Khomein, chiti Ks21189, red Akhtar, red Ks31169, white Pak and white G11867) were studied at constant laboratory conditions (27 ± 2°C, 70 ± 5% relative humidity and 16L:8D h). Immature developmental times of male and female mites were significantly influenced by bean cultivars. This time was significantly longer on white Pak and white G11867 than on the other cultivars, whereas total fecundity per female was higher on red Akhtar than the other cultivars. There were significant differences among the forms of the survival curves of mites on the bean cultivars. Statistical comparisons of the jackknifed intrinsic rate of natural increase (rm ), net reproductive rate (R 0), generation time (T), doubling time (DT) and finite rate of increase (λ) suggest unsuitability of the cultivars white Pak and white G11867 as hosts for the development of TSSM. rm , R 0 and λ of the T. urticae had the highest value on red Akhtar and the lowest on white Pak and T and DT varied significantly on different cultivars and the shortest and longest values were obtained on red Akhtar and white Pak, respectively. The lower population rate of the mite could be the result of antibiotic resistance in the cultivars white Pak and white G11867.

Fitness of Tetranychus urticae Koch (Acari: Tetranychidae) on different soybean cultivars: biology and fertility life-tables

ABSTRACT The quality of the host plant affects the life-history traits of plant-feeding arthropods. The effect of several soybean cultivars on the fitness of Tetranychus urticae was assayed by determining developmental time and fertility life-table parameters for mites on leaf discs at 25 ± 1°C, 70 ± 10% relative humidity and 16 : 8 light : dark photoperiod. Immature developmental time was significantly longer on LWK and Gorgan 3 than on the other cultivars, whereas total fecundity per female was higher on Gorgan 3 than the other cultivars. There were significant differences among the forms of the survival curves of mites on the cultivars. Statistical comparisons of the jackknifed intrinsic rate of natural increase, generation time, doubling time, and finite rate of increase, suggest unsuitability of the cultivars LWK and Gorgan 3 as hosts for the development of two-spotted spider mite. No significant difference was observed for the net reproductive rates among the cultivars. The lower population rate of the mite could be the result of antibiotic resistance in the cultivars LWK and Gorgan 3.

Effects of native plants and IGRs on the development of &lt;i&gt;Tetranychus urticae&lt;/i&gt; Koch (Acari: Tetranychidae)

Effect of the seed dust of yellow karavi (Nerium oleander L.), flower juice of akanda (Calotropis procera L.) and two IGRs (diflubenzuron and triflumeron) were observed on the development of two-spotted spider mite (TSSM), Tetranychus urticae Koch. The seed dust of yellow karavi and akanda juice delayed the development of T. urticae resulting the elongation of duration of different developmental periods. But, the last stage of development was not affected with these treatments. Similarly, the two IGRs also significantly extended the duration of different developmental stages except deutonymph to adult. The different doses of two plant materials and two IGRs produced different effects on the development of two-spotted spider mite.&#x0D; &#x0D; Key words: Tetranychus urticae, Calotropis procera, Nerium oleander, diflubenzuron, triflumuron, developmental period &#x0D; &#x0D; Univ. j. zool. Rajshahi Univ. Vol.25 2006 p.18-22

Effect of Plant Materials on Developmental Periods of Two Spotted Spider Mite, &lt;i&gt;Tetranychus urticae&lt;/i&gt; Koch (Acari: Tetranychidae)

Low concentration of raw flower juice of Calotropis porcera (Asclepiadecae) and seed dust of Nerium oleander (Apocynacae) significantly delayed the egg to adult development of two-spotted spider mite, Tetranychus urticae Koch, for three successive generations under laboratory trial. The flower juice of C. porcera was found more effective than the seed dust of N. oleander in delaying the developmental period of TSSM. Key words: C. porcera, N. oleander, T. urticae, TSSM, developmental period. DOI:10.3329/jbs.v16i0.3753 J. bio-sci. 16: 121-124, 2008