Tetranychus urticae

K, Marie Stephane Tixier, Douin, Martial, Rocio, Oliva, Gonzalez, Lucia, Pount, Benjamin & KreiterK, Serge, 2020, Distribution and biological features of Typhlodromus (Anthoseius) recki (Acari: Phytoseiidae) onTetranychus urticae, T. evansi (Acari: Tetranychidae) and Aculops lycopersici (Acari: Eriophyidae), Acarologia 60 (4), pp. 684-697 : 688-690

Tetranychus urticae and bean

The average number of eggs laid over 4 days by females T of. (A.) recki , N. cucumeris and N. californicus was significantly different P (= 0.0008) ( Table 2). This was due to the significantly higher fecundity of N. californicus (1.4 eggs/ day/ female) as no difference was observed between the three populations of T. (A.) recki and N. cucumeris . Those differences were not significant at days 1 P (=0.07) and 2 (P =0.06) but were significant at days 3 P (<0.001)

and 4 (P =0.001) ( Table 4, Figure 3a ). For days 3 and 4, the fecundity of N. californicus was significantly higher than that of N. cucumeris and T. (A.) recki . Differences in fecundity through the time were only observed for N. californicus , a higher fecundity being observed at days 3 and 4 than at days 1 and 2 ( Table 4). Even if not significant, we can note that among the T.

(A.) recki populations, the highest daily fecundity was observed for the population collected on Datura stramonium L. (0.95 eggs/ day/ female) and the lowest for the population collected on S. lycopersicum L. (0.57 eggs/ day/ female) ( Table 2).

The number of T. urticae eggs consumed by the populations/species was significantly different (P = 0.02) ( Table 3). The highest mean consumption was observed for T. (A.) recki collected on S. lycopersicum (18.47 eggs consumed / day) and the lowest for N. californicus (10.67 eggs consumed / day) and T. (A.) recki collected on M. suaveolens (11.69 eggs consumed

/ day). The numbers of eggs consumed were significantly different at day P <1 0.001 (), day

3 (P =0.05) and day 4 P (<0.001) ( Table 4). At day 1, T. (A.) recki from S. lycopersicum showed the highest consumption (40.5 eggs consumed) and N. californicus the lowest (6.0

N° eggs laid/female feeding on T. urticae N° eggs laid/female feeding on T. evansi

6 (a) 1.4

1.2

5

1

4

0.8

3

0.6

2

0.4

1 0.2

0 0

T. (A.) recki T. (A.) recki T. (A.) recki N. N. T. (A.) recki T. (A.) recki T. (A.) recki N. N.

D. S. M. californicus cucumeris D. S. M. californicus cucumeris

N° eggs consumed /female feeding on T. urticae N° eggs consumed /female feeding on T. evansi

80 20

70 18

16

60

14

50

12

40 10

30 8

6

20

4

10

2

0 0

T. (A.) recki T. (A.) recki T. (A.) recki N. N. T. (A.) recki T. (A.) recki T. (A.) recki N. N.

D. S. M. californicus cucumeris D. S. M. californicus cucumeris

N° eggs laid/female feeding on A. lycopersici eggs consumed). At day 3 and 4, the highest values were observed N for. californicus (Table

4). Egg consumption significantly decreased from day 1 to day 4, except for N. californicus for which they increased ( Table 4). The mean number of eggs consumed during 4 days was the highest (73.9) for T. (A.) recki from S. lycopersicum . For the other populations of T. (A.) recki ,

this consumption was about 50 eggs ( Figure 3c ).

There are no data on biological features of T. (A.) recki in literature. Differences between the three populations were observed but they were relatively low, except for the population collected on S. lycopersicum that consumed significantly more T. urticae eggs than the two others. Globally, T. (A.) recki has low transformation rates: many eggs of T. urticae need to be consumed to produce one Phytoseiidae egg (especially for the population collected on S. lycopersicum ). These results are in accordance with biological features (observed in experimental conditions comparable to the present ones: 18 °C­25%C, 65%­ 75% HR and

16D:8N ­ 18D:6N) of other generalist Phytoseiidae species. For instance, Kasap (2010) showed for Kampimodromus aberrans (Oudemans) , a low consumption rate (2.85 eggs /

day) of T. urticae and a mean fecundity of one egg per day. Zemek (1993) indicated a low fecundity for Typhlodromus (Typhlodromus) pyri Scheuten when fed with T. urticae (0.72 eggs

/ day). Basheer et al. (2014) observed for Typhlodromus (Typhlodromus) athiasae Porath & Swirski , a daily consumption of 10 T. urticae eggs and a mean fecundity of 1.42 eggs/day. The consumption and oviposition rates reported in the literature for N. californicus are variable depending on the populations considered and the environmental conditions. Globally, the mean fecundity is about 2 eggs /female/day ( Gotoh et al. 2004 ; Lebdi­Grissa et al. 2005 ; Canlas et al. 2006 ; Rhamani et al. 2009; Marafeli et al. 2014), but lower values were observed by Hatherly et al. (2005) (0.62 eggs/day) and Castagnoli et al. (2001) (1.46 eggs / day). The fecundity here observed (1.61 eggs/day) show an intermediary value; such differences might be due to strain effects ( Castagnoli et al. 2001). Regarding T. urticae egg consumption, the present results (10.7 eggs consumed/ female/ day) are similar to those obtained for several strains N of. californicus by Castagnoli et al. (2001) (9.09 ­ 11.41) and a bit lower than the data obtained by Canlas et al. (2006). For N. cucumeris , the fecundity here observed is much lower than that reported by Al­Azzazy et al. (2018). The daily T. urticae egg consumption (14.52) is in accordance with values obtained by Li & Zhang (2016) and Zheng et al. (2017) and higher than those reported by Al­Azzazy et al. (2018).

Figures

Figure 3 Cumulated number of eggs laid through the timeT. by(A.) recki (D: collected onDatura stramonium, S: collected onSolanum lycopersicum, M: collected onMentha suaveolens), N. californicus andN. cucumeris when fed with (a)T. urticae, (b) T. evansi and (e)A. lycopersici. Number of prey eggs consumed byT. (A.) recki, N. californicusandN. cucumeris when fed with (c)T. urticaeand (d)T. evansi.