Influence of planting date on the relationship between populations of Frankliniella flower thrips and predatory bug Orius niger in cotton

Abstract

The influence of three planting dates [midMarch (early-planted), 15 April-15 May (normal-or timely planted) and mid-June (late-planted)] of cotton variety SG 125 on the relationship between populations of Frankliniella flower thrips (Thysanoptera: Thripidae) and the predatory bug, Orius niger (Wolff) (Hemiptera: Anthocoridae) were investigated in Adana province in the Eastern Mediterranean region of Turkey in 2003 and 2004. To facilitate emergences of cotton seedlings in early-plantings, cotton rows were mulched after sowing. Adult Frankliniella occidentalis (Pergande) dominated the thrips populations in flowers and colonized the flowers rapidly with high numbers in early-and normal-planted cotton, while adult F. intonsa (Trybom) were significantly more abundant on flowers in late-planted cotton (P B 0.05). The significantly higher but short-lasted larval developments were detected only in late-planted cotton in both years (P B 0.05). Although some scarring and silvering damage on leaves and bolls caused by larval feedings occurred in the late-planted cotton, Frankliniella flower thrips did not have any detrimental effect on plant developments and cotton yields in any of the plantings. Early-and mulchplanted cotton produced significantly higher numbers of fruiting parts and also cotton yield, followed by normalplanted cotton (P B 0.05). We commented that the lower cotton yield in late-planted cotton were due to physiologically caused abscissions of the fruiting parts under unfavourable climatic conditions. O. niger was an effective predatory insect of Frankliniella thrips in the flowers especially in normal-planted cotton, as it was detected in significantly high numbers and thrips-to-predator ratios were lower. It is suggested that early planting of cotton in March could be a good cultural practice in the Mediterranean region.

The abundance of Orius niger (Wolf.) and O. minutus (L.) in potato fields and their life table parameters when fed on two prey species

“…There are also other important biotic and abiotic factors that can aVect the abundance of these predators. Atakan and Gencer (2008) concluded that the populations of O. niger were more abundant in normalplanted cotton Welds and its population density signiWcantly correlated with the Frankliniella occidentalis (Pergande) population. With regard to predator-thrip interactions, they suggested that O. niger might be an eYcient biological control agent to regulate western Xower thrips, especially in normal-planted cotton.…”

Influence of weedy field margins on abundance patterns of the predatory bugs Orius spp. and their prey, the western flower thrips (Frankliniella occidentalis), on faba bean

“…(Hemiptera: Anthocoridae) are often considered important natural enemies of thrips (Riudavets et al 1995). In Turkey, Orius niger (Wolff) effectively suppresses the Frankliniella flower thrips in cotton fields in the Çukurova region that are not treated with insecticides (Atakan 2006;Atakan and Gençer 2008). Orius spp.…”

INFLUENCE OF COTTON SOWING DATE ON THE ABUNDANCE OF WESTERN FLOWER THRIPS (Frankliniella Occidentalis) AND ITS PREDATORY BUGS Orius SPP. IN ÇUKUROVA REGION OF TURKEY

“…Although in general, Orius densities were relatively greater in late-sown cotton, there were significant and positive relationship between thrips and Orius mean numbers only in early-sown cotton (March 1 or March 5 sowing regime). In previous studies various researchers reported that, populations of O. niger significantly and positively correlated with F. occidentalis population in normal-planted (lateApril or early-May) cotton (Atakan, 2006;Atakan & Gencer, 2008). These differences between studies may be because of different sowing date regimes.…”

“…Abundance of coccinellid predator Hippodomia (Adonia), variegata (Goeze) and Orius were appreantly related to cotton sowing date and to the abundance of cotton leafhoppers; fields which were cultivated in early time, proned to get greater densities of predators (Prasifka et al, 2004). In the same ecological area (Çukurova Region), Atakan & Gencer (2008) investigated population densities of the flower thrips in early (Late-March), normal or timely-(Mid-April or Mid-May) and late (June) sown cotton. These researchers reported reduction in the population of insect pest and natural enemies as well as thrips and Orius in early March sown cotton by using mulchsowing technique.…”