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Bu calisma Guneydogu Anadolu Bolgesi’nde farkli depo tiplerinin Khapra boceginin, Trogoderma granarium Everts, 1898 (Coleoptera: Dermestidae), bulasikligina olan etkisi ve zararlinin malathion ve deltametrine olan direncini belirlemek amaciyla yapilmistir. Bolgedeki bes ilden (Diyarbakir, Mardin, Sanliurfa, Adiyaman ve Batman) farkli tahil depo tiplerinden (metal silo, betonarme ve basit sivasiz) 2014-2016 yillarinda nisan-aralik aylari arasinda surveyler yapilmis ve toplam 355 depodan bugday ornekleri alinmistir. Ayrica, direnc calismalari icin farkli depolardan 24 Khapra bocegi populasyonu toplanmistir. Calisma sonucunda, iller ve depo tipleri Khapra bocegi bulasikligina onemli derecede etki etmistir. En yuksek bulasiklik Mardin ilinde (%77.5), bunu takiben Sanliurfa ilinde (%67.5) kayit edilmistir. Buna karsin en dusuk Khapra bocegi bulasikligi Diyarbakir (%43.4) ve Adiyaman (%44.1) ilinde kayit edilmistir. Depo tiplerine gore en yuksek bulasiklik basit sivasiz depolarda (%80) belirlenmis iken, en dusuk bulasiklik metal silolarda (%27.1) bulunmustur. Direnc calismalari, Kapra boceginin deltametrine karsi dusuk duzeyde direnc gelistirdigi, buna karsin malathiona toleransli oldugu gostermistir. Deltametrin uygulanmis populasyonlarin 4-10.7 kat direnc gelistirmis oldugu, ancak malathion icin bu rakamin 1.32-1.92 kat oldugu kayit edilmistir. Deltametrin icin belirlenen yuksek direnc oranlari, malathiona kiyasla bu insektisitin daha sik kullanimini ile ilgili oldugu dusunulmektedir.

[This corrects the article DOI: 10.1371/journal.pone.0236340.].

Cotton (Gossypium hirsutum L.), being a cash and fiber crop is of high significance in Pakistan. Numerous insect pests and viral diseases in Pakistan and around the world attack cotton crop. Genetically modified cotton (transgenic, resistant to lepidopteran insects), hereafter written as 'Bt-cotton' has been introduced in many regions of the world to combat bollworms. However, cultivars differ in their pest susceptibility, yield response and fiber quality traits. Nonetheless, recent studies have indicated that lepidopteran pests are evolving resistance against 'Bt-cotton'. Several 'Bt-cotton' cultivars have been developed in Pakistan in the past decade; however, limited is known about their pest susceptibility, seed-cotton yield and fiber quality traits. This two-year field study evaluated pest susceptibility, yield and fiber quality traits of thirteen newly developed 'Bt-cotton' cultivars in Pakistan. The cultivars differed in their susceptibility to sucking insects during both years of study. The cultivars 'FH-647', 'SLH-8', 'FH-Lalazar' and 'IUB-013' were more susceptible to jassid, whereas 'BS-52' exhibited higher susceptibility to whitefly during both years of study. Similarly, cultivars 'AGC-999' and 'MNH-992' proved highly susceptible to thrips during each study year. Although 'Bt-cotton' is resistant to bollworms, cultivars 'SLAH-8', 'VH-305' and 'BH-184' were susceptible to spotted bollworm, while 'SLAH-8', 'RH-647' and 'VH-305' were infested by American bollworm. The most susceptible cultivars to cotton leaf curl virus (CLCuV) attack were 'RH-647', 'IR-NIBGE-7' and 'VH-305'. The highest seed-cotton yield was recorded for 'FH-Lalazar' during both years of study. Similarly, the highest ginning out turn was recorded for cultivars 'BS-52', 'VH-305', 'RH-647', 'IUB' and 'AA-919'. The cultivar 'FH-Lalazar' exhibited low pest susceptibility and CLCuV infestation compared to the rest of cultivars. The highest and the lowest gross and net incomes and benefit:cost ratio were noted for 'FH-Lalazar' and 'RH-647, respectively. Keeping in view the low pest susceptibility and high seed-cotton yield, 'FH-Lalazar' could be recommended for higher yield and economic returns in Multan, Pakistan. Nonetheless, regional trials should be conducted for site-specific or region-specific recommendations.

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.