Factors influencing thrips abundance and distribution on rose flowers in central India

In commercial rose plantations of central India, population levels of two thrips species, Scirtothrips dorsalis Hood and Thrips flavus Schrank were found high during January–March and low in May–July when monitored for 3-consecutive years. Percentage of infested flowers varied from 14–88% in 1996, 28–95% in 1997 and 37–52% in 1998. Population density varied between 9–44, 10–47 and 11–33 thrips/flower in 1996, 1997 and 1998 respectively. Maximum and minimum temperatures and insecticide applications had significantly negative influence on flower infestation and thrips numbers. Number of thrips collected significantly fluctuated with the level of flower infestation, flower colour, compactness, size, and position of petals. Thrips preferred loose, small sized and red/orange coloured flowers.