Background The two-spotted spider mite, Tetranychus urticae (Koch) (Acari: Tetranychidae), is a widely distributed plant-feeding pest that causes significant yield losses in a wide range of crops. Newly developed or improved environmentally friendly biocontrol agents serve as an alternative to traditional pest control tools. Experiment of the effects of 2 local fungal isolates of Beauveria bassiana (BGF14 and BCA32) was carried out against T. urticae under laboratory conditions. Results Both tested isolates had lethal effect in a short time after application, and this effect increased as time progressed. BGF14 and BCA32 isolates caused T. urticae mortality rates ranging from 25.88 to 61.92 and 32.36 to 62.03% when applied at the concentrations between 1×105 and 1×108 conidia/ml, respectively. According to the Probit analysis performed on the effect of fungi on T. urticae adults, the LC50 values of BGF14 and BCA32 isolates on the 7th day after inoculation were 2.6×106 and 6.3×104 conidia/ml, respectively, and the LT50 values for both fungi applied at a concentration of 108 conidia/ml were 2.14 and 2.23 days, respectively. Conclusions The 2 isolates of B. bassiana (BGF14 and BCA32) had the potentials to suppress T. urticae population and can be recommended as promising biocontrol agent candidates for control of T. urticae.

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Background Potato tuber worm (PTM) [Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae)] is one of the most significant and widespread pests of potato. PTM damages potatoes both in the field and in potato storage areas. Control of the pest is getting harder as it is developing resistance to pesticides. Several entomopathogenic nematode (EPN) species have been reported to successfully control numerous agricultural pests worldwide. The main aim of the study was to isolate native nematode/s as a biological control agent against P. operculella. Morphometric measurements of the infective juvenile (IJ) and sequencing and characterization of the internal transcribed spacer (ITS) region was used to identify the nematode isolate to species level. The efficacy of EPN isolate Z-1 obtained from Zonguldak province, Turkey was tested against different life stages of the pest. Experiments were conducted in 150 ml plastic pots containing sterile soil mixture. Four EPN concentrations (i.e., 0, 250, 500 and 1000 IJs/ml) were applied to the soil. Data relating to the mortality of different life stages were collected daily till 6 days after inoculation. Results Molecular analyses based on the ITS sequence and morphometric data revealed that isolate Z-1 was Heterorhabditis bacteriophora. Mortality rates of PTM larvae exposed to 250, 500, and 1000 IJs/ml concentrations of native EPN were 62.9 ± 9.8, 74.0 ± 3.7, and 92.5 ± 3.7%, respectively. There were non-significant differences among tested EPN concentrations for pupal mortality and the highest concentration (i.e., 1000 IJs/ml) caused 25.6% mortality. Conclusions The results revealed that the native H. bacteriophora isolate was effective against late-stage larvae of PTM under laboratory conditions. Therefore, it can be used as an alternative management option of the pest.

The potato tuber moth, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae), is an important pest of potato that causes yield losses in potato producing countries all over the world. Many management methods are available for reducing this pest populations. Chemical control methods are at the top of these. However, Entomopathogenic nematode (EPNs), can be used as a potential alternative to chemical insecticides to control potato tuber moth larvae as an eco-friendly management method. We aimed in this study to examine the efficacy of Turkish isolates of Heterorhabditis bacteriophora against the last instar larvae (fourth stage) of the potato tuber moth under laboratory conditions. Experiments were conducted in 150 milliliter plastic cups with sterile soil mixture. Four nematode concentrations (0, 250, 500 and 1000 IJs) were applied directly to the soil. Potato tuber moth was susceptible to different concentrations of the H. bacteriophora isolate. All doses were more effective than the control (water). The most effective was the 1000 IJs concentratio, providing a high mortality rate of the last instar larvae of potato tuber moth. No statistically significant difference was observed among temperatures. These results indicated that this H. bacteriophora isolate is very efficient and could be used against potato tuber moth in biological control programs.

Bu çalışma, Rize iline ait ilçelerdeki çay bahçelerinde bulunan akar türlerini tespit etmek amacıyla 2017-2019 yılları arasında gerçekleştirilmiştir. Çalışma süresince, 9 ilçede tesadüfi örnekleme yöntemi ile çay bitkisinin 1., 2. ve 3. sürgün dönemine denk gelecek şekilde Mayıs-Eylül ayları arasında sürvey çalışmaları yürütülmüştür. Çalışma süresince, 1. sürgün döneminde 9 ilçede toplam 73 çay bahçesinde, 2. sürgün döneminde 107 çay bahçesinde ve 3. sürgün döneminde ise 97 çay bahçesinde arazi çalışmaları yapılmış ve çay örnekleri toplanmıştır. Çalışma sonunda en yaygın ve en yüksek sayıda tespit edilen tür Sarı çay akarı olmuştur. Belirlenen diğer akarlar ise; Calacarus carinatus, Brevipalpus phoenicis, Tydeus californicus, Neoseiulus californicus, Czenspinskia transversostriata, Tuckerella sp., ve Oribatida türleridir. Bu çalışmada bulunan akarlar, farklı fenolojik dönemler hakkında bilgi eksikliğini giderecek nitelikte olup, daha önceki yıllarda yapılan çalışmalarla bütünleşecek şekilde tamamlanmıştır.

This study was carried out to determine the damage of the European sunflower moth [Homoeosoma nebulellum (Den. & Schiff.)] to sunflower (Helianthus annuus L.) cultivation areas in Ankara and the relationship of Homoeosoma nebulellum (Den. & Schiff.) to Head rot disease (Rhizopus spp.) that causes loss of yield in sunflower between 2013-2014. Data were collected from Ayaş, Bala, Beypazarı and Kalecik districts between 2013 and 2014 where sunflower cultivation is predominant. The prevalence of H. nebulellum was observed as 100% for both years. The pest infestation rate was determined as 3.74% and 3.80% in 2013 and 2014, respectively. Rhizopus stolonifer (Ehrenb.) Vuill. was observed as the species that causes head rot disease in Ankara, and its prevalence was 76.68% and 70.42% in 2013 and 2014, respectively. The transmission rate of this disease was determined as 4.08% and 4.04% in 2013 and 2014, respectively. When the Chi-square correlation coefficient test was applied to the obtained results, a 72.4% relationship was determined between the pest and the disease. This study shows that the European sunflower moth is not only the main cause of damage to sunflower but also an important factor in the infestation of head rot disease.

Sebzeler tüm yıl taze olarak tüketilen önemli besin grupları arasında yer almaktadır. Son yıllarda yaprağı yenen sebzelerde bazı zararlılar önemli sorun olarak ortaya çıkmıştır. Bu sorunların tespit edilmesi amacı ile Orta Anadolu Bölgesi'nde yaprağı yenen sebzelerin yoğun olarak üretiminin yapıldığı Ankara, Eskişehir ve Konya illerinde marul, maydanoz, nane, dereotu, tere, roka ve ıspanakta üretimi kısıtlayan zararlıların tespit edilmesi amacıyla çalışmalar 2015 ve 2017 yılları arasında yürütülmüştür. Bu amaçla sürveyler belirlenen illerde tarla döneminde zararlıların bulunduğu bitkilerden uygun yöntemlerle toplanmıştır. Yapılan çalışmalar sonucunda toplanan böceklerin Coleoptera, Hemiptera, Lepidoptera, Thysanoptera ve Diptera takımına ait zararlılar olduğu saptanmıştır. Roka ve terede zararlı olan Toprak pireleri Phyllotreta atra ve Phyllotreta cruciferae ve marulda ise Nasonovia ribisnigri, Aphis gossypii, Helicoverpa armigera tespit edilen zararlılar arasından önemli türler olarak yer aldığı belirlenmiştir.

Background The cotton leafworm, Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae), is an economic pest on various crops worldwide. Farmers generally used to apply chemical pesticides to control the pest. The bio-control potential of the entomopathogenic nematodes (EPNs) as alternatives to harmful synthetic pesticides was examined in this study. The study aimed to determine the efficacy of EPNs isolates against the different stages of larvae of the cotton leafworm S. littoralis and the effect of time on mortality rate under laboratory conditions. Results EPNs isolates were tested at 4 different concentrations (0, 250, 500 and 1000 IJs/ml) in 150 ml plastic containers on last instar larvae (sixth instar) of S. litorallis. Experiments for third, fourth and fifth instar larvae of S. litorallis were carried out in petri dishes at different concentrations (0, 50, 100 and 200 IJs/ml) at 25 °C temperature. Mortality rates of larvae were calculated at 3 different times (48, 72, 96 h) after inoculation. The high mortality rate of last instar larvae (98.81%) of S. littoralis was caused by Steinernema feltiae (Tokat-Emir), followed by S. carpocapsae (Tokat-Bakışlı05) (95.24%) and then H. bacteriophora (11 KG) with (90.47%) at the highest concentration (1000 IJ/ml). The highest mortality rate of fifth instar larvae was caused by S. feltiae (Tokat-Bakışlı05) and S. carpocapsae (Tokat-Emir) with (100%) and (92.12%). In addition, the highest mortality rate of the 4th instar larvae was determined S. feltiae (Tokat-Bakışlı05) and S. carpocapsae (Tokat-Emir) isolates (98.87%) and (97.74%), respectively. Additionally, the highest larval mortality rate in the third stage by S. feltiae (Tokat-Bakışlı05) and S. carpocapsae (Tokat-Emir) was (100%) and (97.74%) at the highest concentration. Mortality rates of larvae were calculated at 3 different times after inoculation. The highest mortality rate counted in all isolates was determined 96 and 72 h after inoculation of EPNs. Conclusions All indigenous EPN isolates were found to be effective at different rates against S. littoralis. The results showed that these nematode species could be used against S. littoralis biological control programs.