Drinking-water supply remains a significant challenge in tropical areas; to help meet this challenge, the purpose of the present study was to manufacture low-thermal conductivity ceramic membranes suitable for the retention/removal of particles found in non-potable water. These membranes with significant chemical and mechanical resistances were developed from Cameroonian clays, cassava starch, and bovine bone ash. Up to 30% of Cassava starch and bovine bone ash were added to the membrane as porogens (materials used to make pores in membranes). Membranes were manufactured by uniaxial pressing, drying at 105°C, and sintering at 1150°C for 2 h. The effects of various types of porogen on the thermal behavior, microstructure, flexural strength, porosity, and permeability of ceramic membranes were investigated to determine possible applications of those membranes for water filtration in the tropics. The thermal conductivity of membranes produced without a pore-forming agent (SM0) was greater (0.54 Wm–1K–1) than those produced with starch (SM1 and SM3) (0.45–0.40 Wm–1K–1) or bovine bone ash (SM2) (0.49 Wm–1K–1). The total porosity of SM0s (30.72%) was less than those of starch and bovine bone membranes (37.87–45.99%). The average pore size (0.04 μm) of SM2 membranes was the smallest: SM0 (0.09 μm), SM1 (0.10 μm), and SM3 (0.07 μm). The maximum pore size was 0.37 μm, indicating that membranes contain mesopores and macropores. The flexural strengths of SM1 and SM3 membranes (8.85 and 6.97 MPa, respectively) were less than those of SM2 (10.53 MPa) and SM0 (10.28 MPa), and water permeability from 108 L/h·m2 bar to 2198 L/h·m2 bar. Filtered water properties showed that pH values were upgraded from 5.9 to 7, the turbidity reduction rates and levels were >94% and <0.65 NTU. Particle-size distributions moved from 1150–39,000 nm in polluted water to <2 nm in filtered water. Judging by the sizes of particles present in filtered waters, these membranes may be suitable for elimination of viruses, pigments, proteins, colloids, and bacteria.

Whiteflies are one of the major pests of tomato under greenhouses, and their control partly relies on biocontrol strategies. Among those biocontrol agents, parasitoids or predators are widely used. However, the introduction of a biocontrol agent in a new area is not trivial. For that reason, we investigated the use of a tropical native mirid, Nesidiocoris volucer (Hemiptera: Miridae), for the biological control of whiteflies among other insect pests on tomato crops under greenhouses in the subtropical island of La Réunion, France. Nesidiocoris volucer life history traits and plant injury were examined. Nymphs developed and survived between 15 and 30°C and required on average 49.41 days at 15°C and on average 10.50 days at 30°C to develop (nymph survival >94%). At 25°C, each female produced on average 65 eggs. Nesidiocoris volucer was able to feed on several prey species, but performed better on whiteflies than on spider mites or thrips. No N. volucer feeding injury was observed on tomato. Nesidiocoris volucer has also been found in tropical countries of Africa, and we believe that the data presented on this natural enemy could be of great importance for the biocontrol of whiteflies in tropical areas.