Ovipositional Responses of the Pulse Beetle,Bruchus chinensis(Coleoptera:  Bruchidae) to Extracts and Compounds ofCapparis decidua

Abstract

Extracts of Capparis decidua stems and flowers showed insecticidal and oviposition inhibitory activities against Bruchus chinensis. The LC50 values of these extracts were found to increase with the increase in the polarity of the extract at different exposure periods. For instance, after 96 h, the LC50 values were found to be 3.619, 7.319, and 10.151 microg for CD1, CD2, and CD3, respectively. Extract CD7 was effective only at higher doses. The toxicity was found to be dose- and time-dependent. The females laid lesser number of eggs, when exposed to sublethal doses of different extracts and pure compounds, as compared to control. The maximum oviposition deterrence index was found for extract CD1 followed in decreasing order by CD2, CD3, and CD7. From extract CD1, two compounds were isolated and characterized as triacontanol (C1) and 2-carboxy-1,1-dimethylpyrrolidine (C2). When the females were exposed to sublethal doses of these compounds, they laid lesser number of eggs as compared to the control. C2 was found to have a slightly greater oviposition inhibition effect than C1. From fraction CD7, one novel compound labeled as CDF1 has been isolated and identified as 6-(1-hydroxy-non-3-enyl)tetrahydropyran-2-one. CDF1 has also shown insecticidal and oviposition inhibitory activities against B. chinensis at low concentrations.

Fumigant Toxicity of Essential Oils from Some Common Spices against Pulse Beetle, Callosobruchus chinensis (Coleoptera: Bruchidae)

“…Thus, it is an urgent need to develop certain new alternatives that must be biodegradable, ecologically safe with no residual activity and adverse effect on other non-target animals. In this direction, many products of botanical origin have been evaluated for their toxic properties against different stored grain pests [7][8][9][10] especially in form of essential oils [11][12][13][14][15] . Besides crude essential oils, their constituents have also been evaluated for toxicity against stored product insect pests 16,17) .…”

Organic cultivation of field pea by use of products with different action

“…Thus, there was no possibility to compare own results with those obtained by other researchers. But it has been found in many experiments that combined application of synthetic growth regulators, fertilizers and insecticides improves growth and productiveness of forage crops -pea, vetch and lucerne (Tsibulko et al, 2000;Georgieva & Nikolova, 2010a,b). A number of producers of growth regulators recommend their joint application with leaf fertilizers and preparations for plant protection, by which the effect of the used preparation increases.…”

“…A number of producers of growth regulators recommend their joint application with leaf fertilizers and preparations for plant protection, by which the effect of the used preparation increases. According to data of Tsibulko et al (2000), the best technological method of treatment with growth regulators is their joint application with insecticides. The results showed a yield increase of 14%, as against the control, after treatment with growth regulator Ferocor and 17 to 21% after combination of Ferocor with an insecticide (BI-58, Karate, Basudin and Fosalon).…”

“…al., 2002) are safer and at same time toxic to phytophagous insects. They provoke very high mortality in the bruchids (Upadhyay et al, 2006) and control grain damages efficiently (Sabbour & Abd-Al-Aziz, 2007). Among the numerous plants having an insecticidal or insect-repellent effect, two plants, namely Chrysanthemum cinerariaefolium (pyrethrum) and Azadirachta indica (neem) have gained great importance for insect control, including seed pests (Reuben et al, 2006).…”

“…Mixed use of insecticides (pesticides) with growth regulators, stimulants and foliar fertilizers, as an element of the modern technology in convential production, increases the effectiveness of the preparations (Tsibulko et al, 2000), allows reducing their doses (Stoeva & Shaban, 2001) and has a high economic effect saving time, energy and costs (Petroff, 2008). The investigations about effectiveness, compatibility and stability of such combinations among organic products, differing in their biological effect, are still in an initial stage in Bulgaria.…”