The first article in this issue is about the work done in the USA on many variables of pest pressure, including estimated arthropod-related yield losses, percentage of affected area, direct control costs and insecticide sprays. Yield losses attributable to arthropods, individual pests and the cost of direct control are measured every year in a nation-wide survey under a project funded by The Cotton Foundation. The same sources have been used since 1979 to collect the same information, thus providingan excellent database on long-term changes and shifts in the criteria mentioned above. A review of the last 20 years of data show that the boll weevil and bud/bollworms in 1993/94 were responsible for 84% of all yield losses, which were estimated to amount to 6.9% of potential yields. Over the last two decades, the intensity of arthropod damage has changed significantly in the USA. The boll weevil eradication program, the planting of biotech cotton and other programs have lowered yield losses to less than 5% since 2001/02 and only 2.06% in 2012/13. The whitefly population was already on the decline in 1993/94. Now, thrips are causing more loss in yield than bollworms. There is a consensus in the cotton community in the US that Lygus bugs are on the increase, but the data do not seem to support that contention. The article proyides a good view of the arthropod situation and changes in the pest pattern.
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