The cereal cyst nematode, Heterodera filipjevi (Madzhidov) Stelter, was detected in Turkey in 1996 and since then it has been increasingly reported to cause losses in wheat yields. Cereal cyst nematode populations have a wide genetic diversity which makes it difficult to be managed. The objectives of this research were to investigate the genetic variation of 23 cyst nematode populations collected from wheat growing areas of Bolu Province, utilising sequenced ITS-rDNA regions, and monitoring main nematode isolate population dynamics in field conditions. The results of ribosomal DNA sequencing revealed that all cyst populations were H. filipjevi and that little genetic variation was present among populations. The highest number of second-stage juveniles was observed between April and beginning of May in a field experiment; white females were visible on the roots in late May. The hatching process was positively correlated with low temperatures, but there were inverse correlations between reproductive factors and initial nematode population densities.

Stem borers (Lepidoptera) are common cereal pests. In many parts of the world, the species Ostrinia nubilalis and Sesamia nonagrioides stand out as important insect pests of economically important crops such as maize. Their management relied mainly on transgenic host plant resistance over the last 25 years. Technologies based on the insecticidal properties of Bacillus thuringiensis-derived proteins allowed widespread pest population suppression, especially for O. nubilalis. However, the recent discovery of Bt resistance, which has revitalized interest in both pests' biology and management, may jeopardize the effectiveness of such transgenic technologies. Historical information on O. nubilalis bionomy may need to be reassessed in light of changing climate conditions and changing agricultural practices, as well as increased production of alternate host crops across its distribution range. The current paper examines the bioecology and historical research that has been conducted to manage these two important maize-boring pests.

No abstract

ÖZET: Fasulye tohum böceği, Acanthoscelides obtectus (Say) (Coleoptera: Chrysomelidae), başta fasulye olmak üzere nohut, mürdümük ve börülcede zarara neden olan bir türdür. Acanthoscelides obtectus birden çok döl verebilme özelliğinden dolayı hem arazide hem de depoda ciddi problemlere neden olmaktadır. Zararlının beslenmesi sonucu baklagillerin besin değeri düşmekte, tohumda çimlenme, kalite ve ağırlık kayıplarına neden olmasının yanı sıra taneyi beslenme artıkları ve dışkılarıyla kirletmektedir. Acanthoscelides obtectus iç ve dış piyasada önemli yeri olan baklagillerin pazar değerini de büyük oranda düşürmektedir. Bu nedenle, A. obtectus ile mücadele depo ve tarlada titizlikle yürütülmelidir. Zararlıyla mücadelede öncelikle kültürel önlemlere dikkat edilmelidir ve bu amaç için sertifikalı tohum kullanılmalı, zarar görülen tarlalarda geç ekim yapılmalıdır. Hasat geciktirilmemeli, hasat sonrası kalan bitki artıklar derine gömülmeli veya yakılmalıdır. Kimyasal mücadelesinde bitkisel ekstraktlar (ökaliptus yağı ekstraktı ve tesbih ağacı bitkisinin methanol ekstraktı vb.) kullanılmasına öncelik verilmelidir. Baklagil ekimi yapılan tarlalarda zararlıyla mücadele faydalı böceklerin varlığı göz önünde bulundurularak ilaçlama yapılmalıdır.

Members of Trichogramma genus are the most widely used as natural enemies in biological control programs. Choice of natural enemies is known to have a critical important for the succession of biological control. Their morphologic identification has some bottlenecks as laborious, time-consuming and mostly based on very small structures of the bodies. Molecular techniques have been widely used for detection, discrimination, phylogenetic analysis, identification and characterization in biological control agents belong to Trichogramma spp. In this study, the efficacy of the direct sequencing analysis of internal transcribed spacer locus of rDNA was investigated for analyzing the genetic variation within nine Trichogramma brassicae population from corn growing areas in Düzce province. The comparison of the sequences was performed with other ITS2 locus of Trichogramma species available in GenBank database. The result of analyses indicated that no genetic variation was determined in the Düzce population.