Making Plants Smell Like Moths: Nicotiana benthamiana release moth pheromone alcohol, aldehyde and acetate upon transient expression of biosynthetic genes of different origin

Using genetically modified plants as natural dispensers of insect pheromones may eventually become part of a novel strategy for integrated pest management. In the present study, we first characterized essential functional genes for sex pheromone biosynthesis in the rice stem borer Chilo suppressalis (Walker) by heterologous expression in Saccharomyces cerevisiae and Nicotiana benthamiana, including two desaturase genes CsupYPAQ and CsupKPSE, and a reductase gene CsupFAR2. Subsequently, we co-expressed CsupYPAQ and CsupFAR2 together with the previously characterized moth desaturase AtrΔ11 in N. benthamiana. This resulted in the production of (Z)-11-hexadecenol together with (Z)-11-hexadecenal, the major pheromone component of C. suppressalis. Both compounds were collected from the transformed N. benthamiana headspace volatiles using solid phase microextraction. We finally added the expression of a yeast acetyltransferase gene ATF1 and could then confirm also (Z)-11-hexadecenyl acetate release from the plant. Our results pave the way for stable transformation of plants to be used as biological pheromone sources in different pest control strategies.

Incidence and relative abundance of rice stem borers in three selected rice fields in Lagos and Ogun States, Nigeria

This study was conducted to investigate the incidence of rice stem borer infestations and the species composition present in the selected rice fields. Data were collected between April 2017 and November 2018 across three locations, which include the upland rice field in Agbajege, Ogun state, rainfed lowland in Itoikin and Mangrove swamp in Igbogun, Lagos state, respectively. The incidence of rice stem borers was indicated by dead heart and white heads symptoms, while tillers were excised for rice stem borer identification and population. Results showed a high and low incidence of rice stem borers with no significant difference(p>0.05) at p= 0.29 and 0.37 between the early and late planting seasons in the rainfed lowland and upland rice fields respectively. Planting seasons were significant in the incidence of rice stem borers in mangrove swamp rice fields at p<0.05, p=0.01). This study showed that the predominant species of rice stem borers present in the three study sites were Chilo zacconius and Sesamia calamistis. C. zacconius was the most abundant species at 89% while S. calamistis was 11%. Rice stem borer populations were significantly higher at (p<0.05, p=0.000) in flooded zones while the highest rice stem borer populations were observed at the reproductive phase of the rice plants. Thisstudy showed that the planting seasons coincided with the peak period of the development of rice stem borers. Hence, conservation of natural enemies, monitoring and surveillance should be adopted in insect pest management in rice agroecosystems

UJI ATRAKTAN PADA EKSTRAK PURUN TIKUS (Eleocharis dulcis) SEBAGAI PERANGKAP HAMA PENGGEREK BATANG PADI PUTIH

Purun tikus (Eleocharis dulcis) are wild plants found on swamp land which are quite abundant in South Kalimantan. This research was conducted to find out the most active extract from Chinese water chestnut as an attractant of white rice stem borer (Scirpophaga innotata). Purun tikus were made into extracts using the stepwise extraction method using n-hexane, ethyl acetate, and methanol, with yields of 0.74%, 0.81%, and 7.58%, respectively. The results of the attractant test on purun tikus extract showed that the extract of n-hexane purun tikus was the most active extract as an attractant in white rice stem borer (Scirpophaga innotata). The results of the analysis using GC-MS showed that the extract of n-hexane purun tikus contained several compounds, namely 2-methyltetrahydrofuran, isopulegol, citronellal, citronellyl acetate, βcitronellol, Z-citral, 1-bromo-3,7-dimethyl-2,6-octadiene, citral, linalyl acetate, trans-caryophyllen, trans-phytol, verticellol.

Komposisi Spesies Penggerek Batang Padi dan Parasitoid Telurnya pada Ketinggian Tempat yang Berbeda

Composition of Rice Stem Borer Species and Their Egg Parasitoids at Different Altitudes. Rice stem borer is one of the main pest of rice plants that always percolating and attack plants in the field. The pests can result in damage to plants and lost of the grain from season to season. The aim of this research is to know composition and dominance rice stem borer species and role of their eggs parasitoid at an altitude of different places. Research is done by survey based on the height of different altitude in rice plants two weeks after cropping up until eleven weeks after planting. Research conducted from April until August 2019 in rice field that belonging to farmers at Subak Cemagi Let, Cemagi Village and Subak Teba, Mengwi village, Badung regency, Bali province. Subak Cemagi Let are at an altitude of 15 meters above sea level whereas Subak Teba are at an altitude of 300 meters above sea level. Identification of Rice stem borer larvae and their eggs parasitoid done in Pest Laboratory, Agriculture Faculty of Udayana University. Found three species rice stem borer in the height 15 mdpl namely Scirpophaga incertulas; Sesamia inferens dan Chilo suppressalis, whereas in the height 300 mdpl found four species namely Scirpophaga incertulas, Sesamia inferens, Chilo suppressalis, dan Chilo polychrysus. S. incertulas was the most dominant at the two different altitude. Three species of eggs parasitoid that have role to suppress the development of rice stem borer at the different altitude namely Tetrastichus schoenobii, Telenomus rowani dan Trichogramma japonicum. T. schoenobii was the most dominant to suppress rice stem borer populations.

Maliarpha separatella (African white rice borer).

M. separatella is a stem borer of sub-Saharan and Indian Ocean islands and is the only rice stem borer that has widespread distribution in sub-Saharan Africa. Damage by M. separatella includes reduced plant height, total number of grains per panicle, number of filled grains per panicle and grain weight, depending on the plant stage attacked.

Effectiveness Test of Parasitization by Parasitoid Tricogramma japonicum in Controlling White Rice Stem Borer (Scirphopaga innotata)

Rice is an essential food crop besides corn and soybeans. The need for rice each year increases along with population growth. One of the pests affecting rice is the white rice stem borer. The present research aimed to test the effectiveness and to examine the interaction between plant age and the number of Tricogramma japonicum parasitoid. The research was carried out at the Agrotechnology Laboratory of the Faculty of Agriculture, Khairun University, Ternate, and the rice fields of Bumi Restu village SP I, East Wasile district. The research design operative was a randomized block design where factor A (A1 = 21 DAS, A2 = 42 DAS, A3 = 56 DAS) was the age of the plant, and factor B (B0 = 0, B1 = 50, B2 = 100, B3 = 150) was the number of eggs of Corcyra cephalonica. Biological control using different amounts of Trichogramma japonicum parasitoid led to different interactions and results for each tested parameter. For the number of egg groups, there was no interaction with plant age, but the treatments which were found effective in suppressing stem borer populations were B2 and B3 (100 and 150). The most effective pias as indicated by damage intensity parameter was B3 (150), which was applied to plants aged 21 DAP. Furthermore, for plant height, different number of parasitoids poses significantly effective results. Percentage unhulled grain of pias B3 (150) causes insignificant damage. For production there is no interaction with plant age, but pias B2 (100) shows high yield. The conclusion is that pias B3 (150) applied to 21 days of plants is very effective in controlling white rice stem borer.

Chilo suppressalis (striped rice stem borer).

This is one of the most important pests of rice in East Asia, India and Indonesia. In East Asia, C. suppressalis occurs together with Chilo hyrax and Chilo christophi. This pest was probably introduced in Spain and Hawaii by humans (Bleszynski, 1970). It is now also present in the Northern Territory of Australia. The species tolerates low to very low temperatures and is therefore present in temperate and subtropical Asia. This low temperature tolerance enables it to adapt to other regions. The fact that C. suppressalis has become established in France, Spain and Portugal indicates the potential for long-distance movements and there would seem to be a real danger that it could be introduced into Africa, or other ecologically favourable areas.