The quality of the host plant affects the life history parameters of tetranychid mites. The biology and fertility life tables of Tetranychus merganser on five host plants (Carica papaya, Phaseolus vulgaris, Capsicum annuum var. glabriusculum, Helietta parvifolia, and Rosa hybrida) were assessed under laboratory conditions at 28 ± 1 °C and 70–80% relative humidity (RH) with a photoperiod of 12:12 h (L:D). The development period of immature females differed among the tested host plants and ranged from 9.32 days on P. vulgaris to 11.34 days on H. parvifolia. For immature males, it ranged from 9.25 days on P. vulgaris to 11.50 days on H. parvifolia. The female survival rate varied from 53.97% on H. parvifolia to 94.74% on P. vulgaris. The highest total fecundity rate was recorded on P. vulgaris (125.40 eggs/female) and the lowest on H. parvifolia (43.92 eggs/female). The intrinsic rate of increase (rm) varied from 0.271 (H. parvifolia) to 0.391 (P. vulgaris). The net reproductive rate (R_O) was higher on P. vulgaris than on the other host plants. The longest mean generation time (GT) was calculated on C. annuum var. glabriusculum and the shortest on Rosa hybrida. The demographic parameters suggest the unsuitability of H. parvifolia as the host for the development of red spider mites, and the best performance of T. merganser was on P. vulgaris.

Tetranychidae family is a major group of mites causing serious damage in agricultural, vegetable and ornamental crops. Avocado bronze mite (ABM), Oligonychus punicae Hirst (Acari: Tetranychidae) causes major crop damage, defoliation and fruit abortion. At present, the control of this mite depends mainly on agrochemicals. Therefore it is necessary to find alternatives to synthetic pesticides that can help minimize environmental impact and health risks for the consumers. The aim of this research was to assess the effect of different concentrations (0.1, 0.5, 1, 5, 10, 15 and 20% (v/v)) of ethanolic extract of Moringa oleifera leaves against adult ABM females. Mites treated with 0.1 and 20% (v/v) of the extract showed mortality of 0.00% and 46.67%, 6.67% and 86.67%, 13.70% and 96.67%, at 24, 48 and 72 h, as compared to the control treatment, respectively. The number of eggs laid and hatch, as well as ABM feeding rates, depended on the extract concentration, which led to a reduction in the growth rate. M. oleifera leaf ethanolic extract has potential to control O. punicae.

The Tetranychidae family includes mites causing severe damage to agricultural fields. The red spider mite, Tetranychus merganser Boudreaux (Acari: Tetranychidae), causes severe damage to several plant species grown as cash crops. Current red spider mite control depends mainly on chemical insecticides. There is a need for alternate control measures that are environmentally friendlier than chemical pesticides. The aim of the study was to assess the effects of Moringa oleifera leaf ethanolic extract at different concentrations (0.1, 0.5, 1, 5, 10, 15, and 20% (v/v)) against T. merganser females. Such effects can serve as a basis to include this compound in integrated pest management programs for the control of red spider mites. Mites treated with 20% (v/v) killed 86.67%, 13.70%, and 96.30% at 24, 48, and 72 h, respectively, as compared to the control treatment. Oviposition, egg hatching, and the damage caused by red spider mites were all reduced at high concentrations. Moringa oleifera leaf ethanolic extract can be used as a powerful bioacaricide for the control of T. merganser.

Magnolia tamaulipana powder extract inhibited egg laying and food intake of adult female Tetranychus urticae. These effects increased according to concentration, being highly effective between 500 and 1000 µg/mL. Thus, this powder extract shows promise as a control agent for spider mites.

Red spider mites, Tetranychus merganser Boudreaux (Acari: Tetranychidae), is an agricultural pest that causes economic losses in papaya and nopal crops in Mexico. The aim of this research was to assess antibiosis and antixenosis as resistance mechanisms in seven host plants (Thevetia ahouai, Carica papaya, Phaseolus vulgaris, Moringa oleifera, Pittosporum tobira, Helietta parvifolia, Capsicum annuum var. glabriusculum) to red spider mites. Antixenosis was evaluated by non-preference for oviposition and feeding, antibiosis by infinitesimal rate of increase, finite rate of increase and doubling time, and the percentage of spider mites mortality. Oviposition and damage by feeding of T. merganser were significantly greater on C. papaya than on the other host plants. The growth rate of the spider mite was significantly lower in P. tobira and T. ahouai than in the other host plants. The percentage of hatched eggs of T. merganser was significantly higher in P. vulgaris than in the other plant species. Based on the demographic parameters, survival, food intake, and oviposition, these results indicated that compared with C. papaya, P. tobira and T. ahouai were more resistant. These results may be due to the fact that they were plants species of different families. The resistant plants can be studied as alternatives in the management of T. merganser.