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The European wheat stem sawfly, Cephus pygmeus (Linnaeus, 1767) and the black grain stem sawfly, Trachelus tabidus (Fabricius, 1775) are important and common pests in wheat growing areas of Turkey. These sawfly species continue to be a threat to wheat production in the southeast Anatolia Region of the country. This study was conducted to determine larval infestation rates and yield losses caused by these sawfly species in common wheat cultivars grown in the southeast Anatolia Region. Durum and bread wheat fields were surveyed to record larval infestation and damage caused by these sawfly species in four provinces (Adiyaman, Diyarbakir, Mardin and Sanliurfa) of the region. A total 100 wheat fields were randomly selected and stem samples were taken from each field during the harvest period. Spike length, mean number of grains, grain weight and 1000-grain weight were recorded from 100 infested and healthy spikes and crop losses were calculated for 16 wheat cultivars.The surveyed provinces significantly differed in infestation rates, with the highest infestation level recorded for Diyarbakir province with a mean of 17.4% (range 2.1- 54.3%), while the minimum infestation was determined in Adiyaman province with a mean of 5.3% (range 1.4-17.3%). Durum and bread wheat cultivars had negligible effects on larval infestation. Spike length of infested wheat plants was reduced by 0.9-14.4% and the mean number of grains and grain weight were reduced by 0.5-19.7% and 7.2-28.5%, respectively. The loss in 1000-grain weight was 8.9% in bread wheat cultivars, while the loss was 7.9% in durum wheat cultivars. It was concluded that the loss in 1000-grain weight reached 10.9%. Therefore, appropriate control measures should be taken against stem sawflies in high-infestation locations.

Chalky spot damage caused by the stink bugs Dolycoris baccarum (L.) and Piezodorus lituratus (F.) (Hemiptera: Pentatomidae) is a serious problem for red lentil production in Southeast Anatolia, Turkey. This study aimed to determine spraying time against stink bugs, based on lentil developmental stages and evaluate potential agronomic methods (early vs. timely harvest and traditional harvest with sickle bar mower vs. combine harvester) to reduce chalky spot. Field trials were carried out during 2011–2012 in three provinces of Southeast Anatolia (Diyarbakir, Mardin and Sanliurfa).Chalky spot damage was initiated at the R6 stage (full seed, seed on nodes 10-13 fill the pod cavities) when the stink bug nymphs started to be observed and the plant had soft immature seeds that were more susceptible to feeding by stink bugs. In early harvested lentil fields, the percentage of chalky spot damage was 0.60 and 0.20 in Diyarbakir and Sanliurfa provinces, respectively. It was lower than that of timely harvest. On the other hand, damaged seed percentage significantly reduced by changing the harvesting from traditional to combine harvesting and damage ratio was 0.90 and 0.00 in Diyarbakir and Mardin provinces, respectively. We conclude that the management to protect lentil crops from stink bug infestations should be initiated at the R6 growth stage, and that crops should be harvested a week earlier using combine harvester to reduce stink bug density and chalky spot damage.