A comparative study on the insecticidal property of Bambusa vulgaris and Bambusa malingensis shoot and leaf extract against green leafhopper (Nephotettix virescens)

Rice is considered one of the staple foods in Southeast Asian countries, most especially in the Philippines. There are many factors needed to be considered in growing rice crops: the soil nutrient, the climate, the water supply, and the fertilizer used as a supplement to crop growth. But one important thing that farmers should consider is the infestation of pests, specifically the green leafhoppers, which is the primary carrier of tungro virus. This virus affects the growth and development of rice crops. This study aims to investigate the insecticidal effect of Bambusa vulgaris and Bambusa malingensis shoot and leaves extract against green leafhoppers (Nephotettix virescens). The extract was obtained by the decoction method. Phytochemical analysis of the two bamboo species has been carried out, as it was found out that both of them contains alkaloids, flavonoids, and glycosides. The results showed that both the shoot and leaves extract of Bambusa vulgaris and the shoot extract of Bambusa malingensis have potential insecticidal activity against Nephotettix virescens. Further research is needed to identify other factors that could strengthen the effectiveness of applying the extract to the insect specimen.

Mosquito Repellent Activity of Tridaxprocumbens Leaves- A Commercial Product

Tridaxprocumbeans is a weed plant native to tropical America and also seen in other tropical regions. Recent studies on the seed germination of Tridaxprocumbeansshowed that they are pH resistance and they are able to grow in sea water. Although Tridaxprocumbeansis used as a medication plant in Ayurveda, the plant is famous for its wound healing and anticoagulation activity in modern days. As it is the asteraceae family, WHO claims that terpenoids and triterpenoids present in them have a strong insecticidal property. This study is carried to know the insecticidal property of tridaxprocumbensleaves against mosquitos.

Assessment of the insecticidal property of the pepper Capsicum annuum extracts on the larval stages of the tomato leafminer Tuta absoluta (Lepidoptera: Gelechiidae).

The aqueous fruit extracts of the pepper Capsicum annuum L. (Solanales: Solanceae) were tested against the four larval stages of the tomato leafminer (TLM) Tuta absoluta Povolny (Lepidoptera: Gelechiidae). Random samplings were made from two greenhouses of Biskra, in the Southeast of Algeria. About 750 to 800 plants of the Sahara variety of tomatoes were planted in both greenhouses. In the laboratory, conditions with temperature, relative humidity (RH) and the photoperiod were 25° to 30°C, from 50% to 60% and 16L: 8D, respectively. A breeding of our species in the laboratory was made during six months of the study. For the toxicological assessments, three concentrations were chosen; 50 mg/L, 100 mg/L and 200 mg/L of the extracts. The results revealed that the extracts of C. annuum were very effective against the larvae of T. absoluta. After 24 h post-treatment, the mortality was less than 25% compared to that after 48h and 72h post-treatment which exceeded 50%. There was a non-significant difference in mortality rates between the four larval stages (F3, 140 = 1.12; P = 0.344). In contrast, highly significant differences existed between the time of exposure (F2, 141 = 26.2; P = 0.001) and the concentrations under study (F3, 140 = 59.6; P = 0.001). J. bio-sci. 26: 25-30, 2018