Development and reproduction of Scirtothrips dorsalis (Thysanoptera: Thripidae) on six host plant species.

Host plants can strongly influence the population performance of insects. Here, we investigated the development, survival, and oviposition of Scirtothrips dorsalis Hood on 6 host plants-Camellia sinensis ( L.) Kuntze (Ericales: Theaceae), Rosa chinensis Jacq. (Rosales: Rosaceae), Capsicum annuum L. (Solanales: Solanaceae), Eustoma grandiflorum (Hook.) G.Don (Gentianales: Gentianaceae), Glycine max (L.) Merr. (Fabales: Fabaceae), and Cucumis sativus L. (Cucurbitales: Cucurbitaceae), and constructed life tables for S. dorsalis on each plant. Significant differences in S. dorsalis development on the host species were observed. The mean developmental period from egg to adult was 11.45 ±â€…0.12 days, 11.24 ±â€…0.13 days, 12.08 ±â€…0.15 days, 12.28 ±â€…0.12 days, 12.67 ±â€…0.10 days, and 13.03 ±â€…0.11 days on C. sinensis, R. chinensis, C. annuum, E. grandiflorum, G. max, and C. sativus, respectively. Significant differences in survival of S. dorsalis were observed, namely, C. sinensis ≈ R. chinensis > E. grandiflorum ≈ C. annuum > G. max > C. sativus. The highest and lowest fecundities of S. dorsalis were recorded on R. chinensis (60.44 ±â€…1.53) and C. sativus (28.64 ±â€…1.02), respectively. Both of the net reproductive rate (R0) and intrinsic rate of increase (rm) of S. dorsalis were the highest on R. chinensis, with the values of 27.63 ±â€…0.58 and 0.142 ±â€…0.002, respectively; while the lowest on C. sativus, with the values of 8.81 ±â€…0.12 and 0.092 ±â€…0.003, respectively. Thus, R. chinensis was found to be the most suitable host, but C. sativus was the least suitable, for population development of S. dorsalis. Our results provide important information for the key control of S. dorsalis among different host plants.

Life table parameters of Amblyseius largoensis, Amblyseius swirskii and Proprioseiopsis lenis (Acari: Phytoseiidae) fed on eggs and larvae of Frankliniella occidentalis.

The immature development and reproduction of the predatory mites Amblyseius largoensis (Muma), Proprioseiopsis lenis (Corpuz and Rimando), and Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae) were investigated using both thrips eggs and first instars of the western flower thrips, Frankliniella occidentalis Pergande, as prey in a controlled laboratory environment at 25 °C and 60% relative humidity. When provided with thrips eggs as food, A. largoensis exhibited a notably shorter immature development period for both males (7.05 days) and females (6.51 days) as compared with A. swirskii (8.05 and 7.19 days, respectively) and P. lenis (8.10 days and 7.05 days, respectively). Amblyseius largoensis also displayed a higher oviposition rate (2.19 eggs/female/day) than A. swirskii and P. lenis (1.79 and 1.78 eggs/female/day, respectively). Moreover, it exhibited the highest fecundity (25.34 eggs/female), followed by P. lenis (24.23 eggs/female) and A. swirskii (22.86 eggs/female). These variations led to A. largoensis having the highest intrinsic rate of increase (rm) at 0.209, followed by A. swirskii at 0.188, and P. lenis at 0.165. However, when the predatory mites were provided with first instars of F. occidentalis, A. swirskii demonstrated a faster immature development period for both males (7.67 days) and females (7.59 days) as compared with P. lenis (9.00 days and 7.86 days, respectively) and A. largoensis (8.47 days and 8.61 days, respectively). While the oviposition rates of P. lenis (1.92 eggs/female/day) and A. swirskii (1.90 eggs/female/day) were similar when feeding on this prey, A. largoensis produced fewer eggs (1.83 eggs/female/day). Further, A. swirskii exhibited the highest fecundity (31.93 eggs/female), followed by A. largoensis (25.71 eggs/female) and P. lenis (23 eggs/female). Consequently, the intrinsic rate of increase (rm) on thrips first instars was highest in A. swirskii (0.190), followed by A. largoensis (0.186), and P. lenis (0.176). In summary, our findings indicate that in terms of life history parameters A. largoensis performs optimally when feeding on thrips eggs, whereas A. swirskii performs best when preying on the mobile first instars of the thrips. These insights into the dietary preferences and reproductive capabilities of the studied predatory mite species have important implications for their potential use as biological control agents against F. occidentalis in agricultural settings.

Anatomía de la agalla en Ficus benjamina (Moraceae) asociada a "thrips" (Tubulifera: Phlaeothripidae) / Gall anatomy in Ficus benjamina (Moraceae) associated with "thrips" (Tubulifera: Phlaeothripidae)

Anatomy of the gall in Ficus benjamina (Moraceae) associated with thrips (Tubulifera: Phlaeothripidae). The galls are generally recognized as abnormal growths of tissues affected by insects when lay the eggs or feed on plant tissues. In, Ficus benjamina the insect Gynaikothrips garitacambroneroi, when feeding on leaf tissues, causes a gall which consists on the bending of the leaves. In this paper we analyzed the ultrastructure of sections of healthy leaves, and leaves with galls of F. benjamina using scanning electron microscopy (SEM). We analyzed the number of stomata per area and found no significant changes, although there is less cuticular wax on the surface of the affected area by the barb. In the leaf area affected by G. garitacambroneroi, bacilli and fungi were observed and eggs of other organisms as possible invaders. Moreover, the inner tissues of leaves with galls had some problems in the differentiation of palisade and spongy mesophylls, and only parenchymatous tissue was observed. Rev. Biol. Trop. 57 (Suppl. 1): 179-186. Epub 2009 November 30.

Las agallas son reconocidas generalmente como crecimientos anormales de los tejidos afectados por insectos cuando estos realizan la deposición de los huevecillos o se alimentan de los tejidos de la planta. En Ficus benjamina la acción del thrips Gynaikothrips garitacambroneroi al alimentarse de los tejidos de la hoja, provoca una agalla que consiste en el doblamiento de la hoja. En este trabajo se analizó la ultraestructura de secciones de hojas sanas y hojas con agallas de F. benjamina mediante el uso de la microscopia electrónica de barrido. Se analizó la cantidad de estomas por área y no se determinó alteración significativa, aunque se observa menor cantidad de cera cuticular en la superficie del área afectada por la agalla. En la zona de la hoja afectada por G. garitacambroneroi se observó bacilos y hongos y huevecillos de otros organismos, aparentemente invasores. Además, en los tejidos internos de las hojas con agallas se pudo determinar problemas de diferenciación de los mesófilos de empalizada y esponjoso, observándose sólo tejido parenquimático.