This is not a recent introduction. Specimens collected in Florida in are in the U. National Museum Denmark Watson listed the genus in his key to thrips of North America.
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Ziouani, Kh. Benzehra, A. Saharaoui, L. Abstract Population fluctuations of Gynaikothrips ficorum Marchal, Thysanoptera, Tubulifera and natural enemies on leaf gall of Ficus retusa in Algeria Monthly fluctuations of thrip populations on Ficus retusa were monitored and parasites and predators in Boudouaou, Algeria, were identified.
Twenty leaves were collected fortnightly from 30 trees from January to December The number of eggs increased significantly in August with 11, eggs and was slightly higher in October with 11, eggs.
Presence was rare in spring and winter. The 1st and 2nd larval stages L1 and L2 overlapped: L1 were present from August to October with 27 and 51individuals respectively, and L2 were present from August to December with 65 to individuals respectively.
Prepupae were active in April and June, reaching 46 and 50 individuals respectively, before increasing to in November. Highest numbers of pupae were observed in June and July The number of adults gradually increased, reaching a maximum of in early December.
Two predators were identified: Montandoniola confusa Hemiptera, Anthocoridae and Nephus peyerimhoffi Coleoptera, Coccinellidae. A parasite, Tetrastichus gentilei Hymenoptera, Eulophidae , was also later identified. Se solapan los estadios larvarios 1 y 2 L1 y L2 : L1 va de agosto a octubre, con 27 y 51 individuos respectivamente, seguido de L2, con 65 y individuos de octubre a diciembre.
Amb aquest objectiu, cada quinze dies es van recollir 20 fulles de cadascun dels arbres seleccionats, durant 12 mesos de gener a desembre de Forty species of the genus Gynaikothrips Zimmermann are cecidophagous or galligenous, and originate from Southeast Asia, but have been described from Africa; they are associated with Moraceae plants and especially infest the ornamental Ficus and fruiting figs causing considerable damage Mound, ; Dang et al. Among these species, Gynaikothrips ficorum Marchal , also known as Cuban laurel thrips and G.
It prefers leaf-gall on Ficus microcarpa L. It has also been found on Eucalysptus sp. Feeding on tender leaves causes the formation of purplish red spots on the underside of the leaves. These become curled and form galls where G. Other pests are also associated with G. Whereas Adactylidium sp. Acari , Pleurotropis sp. Systemic insecticides appear to provide better control than broad-spectrum insecticides that are detrimental to natural enemies that potentially naturally maintain populations of Gynaikothrips at relatively low numbers Arthurs et al.
The aims of this study were to study the monthly fluctuation of G. Map location of sampling area in Boudouaou, Algeria. This area is characterized by a Mediterranean climate with hot summers and cold winters. The precipitation is irregular; it is abundant in November to March and low from April to September, with a total annual rainfall of Sampling and analyses of galls Sampling was carried out randomly on 30 trees.
Twenty leaves were collected from each tree i. Exposure and leaf age were not taken into account. The leaves were placed in plastic bags on which the sampling date, tree number and location were indicated. The fortnightly samples were taken from January to December They were successively bathed in distilled water three times before being mounted in Faure liquid. The identification of G. Statistical analyses Simple analyses of variance were carried out to verify the period of abundance of each stage and to correlate this with the abundance of their enemies in order to test their impact on the thrips.
Results Fluctuation of larval stages The first larval stage L1 was present all year except from mid-May to mid-August. Activity of L1 and L2 overlapped for two periods. The first period was from February to the end of April and the second was from mid-August to the beginning of October. In the first period, the maximum number of individuals was recorded at the beginning of April for both L1 and L2 In the second period, the maximum was recorded at the end of September and early October for both L1 67 individuals and L2 individuals , respectively fig.
Monthly evolution of larvae L1 and L2 of G. Fluctuation of pupal stage The population number of G. Numbers increased slightly at the end of April 46 individuals to reach 50 individuals in mid-June for the prepupae and then individuals for the pupae. Numbers increased again from August to December with highest number at the end of November with individuals for the prepupae and individuals for the pupae fig. Monthly evolution of prepupae and pupae of G.
Fluctuation of G. Their number gradually increased to 4, eggs in early April then declined significantly in mid-May to eggs and in mid-July to The number of eggs later increased, and was highest in early October 11, eggs. Numbers then fell to 6, in November, but increased again in mid-December to 10, eggs.
The adult population was present almost year-round, with the exception of early February to early April when the population was negligible. Adults appeared from the end of April, with individuals, and continued to increase in the following months to reach a peak in early December with individuals fig. Monthly evolution of eggs and adults of G.
Damage of G. Infested leaves dehydrated, hardened and changed color gradually, turning from yellow to brown before falling out on windy or rainy days. This damage did not generally kill the tree but did decrease their ornamental value fig. The G. Predators and parasites of the G. We found three major enemies of G. Montandoniola confusa Streito and Matocq, Hemiptera, Anthocoridae We found this predator to be present in high numbers in summer, reaching 50 individuals in August.
This parasite feeds on all stages of G. Monthly evolution of M. Para las abreviaturas de las fechas ver arriba. Nephus peyerimhoffi Sicard, Oenopia doublieri Mulsant, N. Few individuals of Oenopia doublieri were observed during our sampling. Abundance was significant in February 55 individuals fig. Monthly evolution of N. Tetrastichus gentilei Del Guercio, T. During the surveys it was observed from August to December.
Its population varied from 20 to 34 individuals in August, then dropped in November before starting increasing slightly again to four and 10 individuals respectively in early and late December. Monthly evolution of Tetrastichus gentilei on Ficus retusa in Boudouaou, Algeria. Succession of presence of M. The ladybird N. It remained throughout the year. It was followed in number by M. The parasite T. Based on our observations, M.
It was considered the major predator of several species of thrips. Ordre of succession of predators and parasite of G. Discussion Data from this study indicate great diversity at all stages of G. The number of eggs was particularly diverse and highly significant in August. For the larval stages, abundance was highest in autumn and spring, while for the pupal stage, it was highest in November, likely due to the age of galls and the influence of climatic conditions.
However, the population of this species was highest in August, followed by November and October. The high population of G. The presence of the associated predator and parasites on the same gall leaf may impact the population of G. Other studies consider that the date of planting may be a factor of variation in the number of thrips; Frankliniella fusca swarm in the early plantings of peanuts in April, while this number decreases in late plantings in May and June Todd et al.
According to Paine , the generation of G. He noted that the population of G. However, Arthurs et al. Shogren and Pain mentioned that another factor that may influence the population of thrips is the sampling period. They found the percentage of thrips differed at the same study site over the different sampled years, resulting in an abundance of thrips within the galls.
However, Rivnay found that the population of G. This is comparable to our results and may be due to more abundant and diverse fauna at these times. Among specimens of the gall-associated fauna, we highlighted two major predators, M. Generally, the species of the genus Montandoniola are predators of most thrips Dobbs and Boyd, ; Yamada et al. In this study, G. This led to a sharp decrease in numbers of this predator.
It also impacted on the mortality of eggs, and decreased the population from 11, eggs to about larvae.
Ziouani, Kh. Benzehra, A. Saharaoui, L. Abstract Population fluctuations of Gynaikothrips ficorum Marchal, Thysanoptera, Tubulifera and natural enemies on leaf gall of Ficus retusa in Algeria Monthly fluctuations of thrip populations on Ficus retusa were monitored and parasites and predators in Boudouaou, Algeria, were identified. Twenty leaves were collected fortnightly from 30 trees from January to December
Anthocorid bugs of the genera Orius, Macrotracheliella and Montandoniola seem to be particularly effective predators within the galls Tawfik, ; Tawfik and Ata, ; Pericart and Halperin, ; Paine, Chrysopidae such as Chrysoperla have been found to eat adults and larvae in both California and Egypt. Similarly, Eulophid wasps and Pyemotid mites are widely reported as attacking various stages of this thrips Burks, ; Abreu-Rodriguez, Impact Top of page The host tree, Ficus microcarpa, is widely planted around the world both for decoration and as a shade tree. For example, it provides shade in the market places of many Latin American towns and villages, lines the streets of cities in southern China, and decorates air-conditioned shopping malls in North America. Nurseries producing these trees may suffer problems due to leaf shedding Hong and Men, ; Pelikan,