Plutella xylostella (L.) population control in sowings of spring rapeseed using pheromones

The diamondback moth Plutella xylostella (Linnaeus, 1758) is a common pest of rapeseed and other crops of Brassicaceae family. Annual yield losses and costs of pest control worldwide are estimated at $ 4-5 billion. The pest has an increased tendency to develop resistance to insecticides. The use of traps with synthetic sex pheromone is a modern instrumental method of monitoring P. xylostella. The use of the mating disruption method will effectively decrease pest numbers and reduce the application of insecticides. In 2017-2020, we researched the pheromone activity and evaluated the mating disruption method in the sowings of spring rapeseed at V.S. Pustovoit All-Russian Research Institute of Oil Crops (VNIIMK) (Krasnodar). We established that P. xylostella males were caught in traps with all tested dispenser types. The pheromone showed the greatest activity on the foil-film dispenser (F). The mating disruption method effectively decreased P. xylostella population in rapeseed sowing; the disruption effect by the end of crop vegetation was high and reached 82.5 %.

Enantioselective Synthesis of the Sex Pheromone of Lichen Moth, Miltochrista calamine, and Its Diastereomer

The synthesis of a Miltochrista calamine sex pheromone and its diastereomer has been developed. The key steps of the synthetic approach involved Evans’ chiral auxiliaries and the addition of alkyne to aldehyde, which were firstly applied to prepare this sex pheromone and its diastereomer. The synthetic sex pheromone could be used to trap insects and study physiological and ecological questions of the lichen moth.

The application of sex attractant traps for studying the Zygaenidae (Lepidoptera) fauna of Albania

In Albania, the Zygaenidae family comprises a relatively rich fauna in the Balkans. They have been studied so far using specimens collected only by using entomological nets or by hand-picking. Two groups of sticky Delta traps baited with: 1) a synthetic sex pheromone compound of the Asian species Illiberis rotundata Jordan, 1907 and its opposite enantiomer, alone and in a mixture, and 2) known sex attractants and experimental lures of the genus Zygaena were used in the field in seven localities in southern Albania in 2017 for studying the Procridinae and Zygaeninae fauna, respectively. Four species belonging to the genera Zygaena, Adscita and Jordanita were captured and identified: Zygaena (Zygaena) filipendulae (Linnaeus, 1758), Zygaena (Agrumenia) carniolica (Scopoli, 1763), Adscita (Tarmannita) mannii (Lederer, 1853) and Jordanita (Tremewania ) notata (Zeller, 1847). A. mannii and J. notata were newly recorded in the Counties of Korçë and Gjirokastër. Z. filipendulae was recorded for the first time in the Gjirokastër County and in the municipalities of Prrenjas (Elbasan County) and Finiq (Vlorë County), while Z. carniolica was newly recorded in Prrenjas municipality. Some other sex attractants did not work for either the target species or for other related ones, which we discuss in relation to species cross attraction and geographical variation.

Practical Synthesis and Field Application of the Synthetic Sex Pheromone of Rice Stem Borer, Chilo suppressalis (Lepidoptera: Pyralidae)

Rice stem borer, Chilo suppressalis, is a common and major serious pest of rice, maize, and wheat crops across Asia, Europe, and Oceania countries. Its sex pheromone consists of three analogously compounds, i.e., (Z)-hexadec-11-enal (1), (Z)-octadec-13-enal (2), and (Z)-hexadec-9-enal (3), as long-chain aliphatic internal cis-alkenyl aldehydes. In order to perform an economic and widespread pest control management of rice stem borer, a versatile and efficient synthetic strategy is required. A versatile and efficient synthesis using a common synthetic route for cis-alkenals with high overall yields is described. Commercially available inexpensive aliphatic diols were chosen as starting materials. Two key steps were employed to synthesize the long-chain aliphatic internal cis-alkenes in excellent yields, including the alkylation of terminal alkynes without the utilization of a highly polar aprotic cosolvent and the versatile cis-selective semihydrogenation for the reduction of internal alkynes with excellent stereoselectivity. The results of field tests showed that the synthetic sex pheromone blend was highly effective for the capture of rice stem borer.

Design and placement of synthetic sex pheromone traps for cacao mirids in Ghana

Cacao mirids (Sahlbergella singularis,Distantiella theobromaandBryocoropsis laticollis) were captured in pheromone traps releasing a 2:1 blend of the sex pheromone components of the two first named species in a series of five experiments on cacao (Theobroma cacao) plantations in Ghana. A total of 835 cacao mirids were caught, all male, 95% of which wereS. singularis, 3%D. theobromaand 2%B. laticollis.Two sticky trap and two water trap designs made from locally available materials were as effective for capturingS. singularisand total mirids as the best sticky trap from previously reported studies. Coating the outer surface of a large water trap with sticker increased the catch 4.4×, and 2.7× for a cylindrical sticky trap. Sticker on the outside of the water trap also increased the inside catch ofS. singularisby 76% and total mirids by 71%. The numbers ofS. singularisandD. theobromatrapped increased with increasing trap elevation and were highest around canopy level. Those traps caught an average 12× more mirids than traps at 1.8 m, the height recommended currently. Therefore, large water traps coated with sticker and aligned with the cacao canopy should raise the current capture rates of pheromone traps for cacao mirids about 50×, which may be sufficient for effective pest management by mass trapping without synthetic insecticides.

Design, Synthesis, and Biological Evaluation of the Sex Pheromone of the Asian Corn Borer, Ostrinia furnacalis (Guenée)

A convenient total synthesis of (Z)-12-tetradecenyl acetate (1a) and (E)-12-tetradecenyl acetate (1b), which are the sex pheromones of Ostrinia furnacalis (Guenée), has been achieved. The target mixture molecules, of a cis-to-trans-isomer ratio of 27 to 73, were synthesized in 40% overall yield and through [13C + 1C] synthetic strategy in five steps from commercially available and cheap industrial brassylic acid as key starting material. The electroantennogram (EAG) responses of synthetic sex pheromone to ACB male moths were conducted. The results showed that the target mixture molecules were found to have a good activity and displayed significantly stronger EAG responses ranging from 10 to 1000 μg, and the optimized stimulating dosage of the activity of synthetic sex pheromone to ACB males is 10 μg. Compared with the existing routes, this synthetic approach is operationally simple, good-yielding, and cost-effective, which could serve as a basis for developing the techniques of sex pheromone mass trapping or mating disruption and providing an environmentally benign method to control ACB pests.