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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.

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A study was conducted to determine the optimum container size and rearing density to economize and optimize the mass rearing of Oenopia conglobata (Linnaeus, 1758) (Coleoptera: Coccinellidae) during 2017 in Şanlıurfa, Turkey. The experiment consisted of three types of containers of varying size (106, 310 and 785 ml, regarded as small, medium and large, respectively) and four different rearing densities of O. conglobata (1, 5, 10 and 20 larvae/container, regarded as low, moderate, medium and high rearing density, respectively). Oenopia conglobata was fed with the eggs of Ephestia kuehniella Zeller, 1879 (Lepidoptera: Pyralidae) throughout the study. The highest (100%) larval survival rate was recorded for all containers with low rearing density, whereas the lowest (31.5-35.0%) larval survival was observed in medium containers with medium and high rearing density. Medium containers at low rearing density had the shortest larval development period (8.6 d), while the shortest pupal development period (4.3-4.4 d) was in medium and large containers at medium and moderate density, respectively. The highest rearing cost was computed for small and medium containers at low rearing density, whereas the lowest rearing cost was incurred with large containers at high rearing density. Considering the survival rates, development periods and economic cost incurred; large containers with high rearing density is recommended for the economic and rapid mass rearing of O. conglobata.

Chalky spot damage on red lentil is the most important problem waiting for a solution regarding plant health at lentil cultivation in Southeast Anatolia Region, Turkey. The stink bugs, Piezedorus lituratus (F.) and Dolycorus baccarum L. were subjected to trials in cages and in sprayed and unsprayed plot trials in open lentil fields and fields containing windrowed lentils after harvesting. The study revealed that P. lituratus and D. baccarum feeding on red lentil caused chalky spot damage. Average damage to lentil seeds caused by P. lituratus was 13% and 7.8% and by D. baccarum was 4.9% and 2% in 2010 and 2011, respectively. There was a positive relation between P. lituratus density and chalky spot damage (r =0.788, r 2 =0.621, P=0.000). The study also showed that after the harvesting, the stink bugs gathered under windrowed lentils and continued feeding and causing chalky spot damage. The damage in unsprayed windrowed lentils (6.60%) was approximately 12-fold higher than that in sprayed windrowed lentils (0.57%). Study suggests conduction of future work on environmental friendly control methods of stink bugs and alternative harvesting methods.

The Maize weevil, Sitophilus zeamais Motchulsky (Coleoptera: Curculionidae), is one of important pests of storage maize in Turkey. Laboratory experiments were carried out to investigate the effect of two local diatomaceous earth (Aydın and Ankara) and Silicosec® (Biofa, Germany) against S. zeamais adults at 25 and 30°C and 50-65% relative humidity. Maize grains (cultivar Decalp 6664) were treated with three doses of DEs (1000, 1500 and 2000 ppm) and untreated seeds were regarded as control. The dead adult counts were made 2, 3, 5, 7, 14 and 21 days after DEs. The progeny of S. zeamais was determined separately for each treatment after 60 days from end of the experiment. The highest mortality (100%) of the maize weevil was observed with 2000 ppm Ankara DE on 14 th day after application at 25 °C, which was followed by Aydın and SilicoSec ® DEs (99.0 and 90.1%). The insecticidal activity of native DEs increased with increasing application dose, exposure time and temperature. The highest insecticidal activity at 30 °C was determined for Ankara and Aydın DEs with 2000 ppm on 14 th day (100%), followed by SilicoSec ® (97.9%). All doses of Ankara DE had the highest insecticidal activity than rest of the DEs examined. New adult emergence (F1 offspring) was recorded in all DEs treatments; however, emergence was very low than control treatment. It is concluded that the native DEs (Ankara and Aydın) are very effective and promising against S. zeamais adults and might be used for its successful control in storage maize.

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