Incidence and management of pests of rose Rosa spp.

Abstract

Rose is one of the most common commercial ornamental crops seen in every household garden. Rose cultivation is gaining popularity day by day. Pest and disease infestation is one of the major concerns in rose cultivation. In this present scenario, a thorough knowledge of the pests infesting rose and their management under Kerala conditions is essential for the successful cultivation of roses. In this context, the present study, entitled "Incidence and management of pests of rose, Rosa sp.," was conducted at the Department of Agricultural Entomology, College of Agriculture, Vellayani, during the period 2020–2022. The objectives of the study were to document the pests infesting Rosa spp., their nature of damage and symptoms, natural enemies associated with the pests and to develop effective management practices. The documentation was conducted at 20 locations of Thiruvananthapuram district viz., Amaravila, Anayara, Attingal, Balaramapuram, Chala, Chirayinkeezhu, Gowreesapattom, Karamana, Karikkakom, Kattakada, Nalanchira, Neyyatinkara, Panangode, Peyad, Sreekaryam, Thiruvallam, Uchakkada, Ulloor, Vellayani, and Vembayam. A total of 42 species of pests were recorded in which twenty four were sucking pests and eighteen were chewing pests. Sucking pests documented were black vine thrips (Retithrips syriacus (Mayet)), chilli thrips (Scirtothrips dorsalis Hood), grapevine thrips (Rhipiphorothrips cruentatus Hood), Rhipiphorothrips pulchellus Morgan, redbanded thrips (Selenothrips rubrocinctus (Giard)), gold-tipped tubular thrips (Haplothrips gowdeyi (Franklin)), Haplothrips ganglbaueri Schmutz, spider mite (Oligonychus biharensis (Hirst)), pea aphid (Aphis craccivora Koch), cotton aphid (Aphis gossypii (Glover)), egyptian fluted scale (Icerya aegyptiaca (Douglas)), seychelles scale (Icerya seychellarum (Westwood)), cottony cushion scale (Icerya purchasi Maskell), California red scale (Aonidiella aurantii (Maskell)), mealybug (Planococcus sp.), striped mealybug (Ferrisia virgata Cockerell), spiralling whitefly 100 (Aleurodicus dispersus Russell), whiteflies (Unidentified sp. 1, Unidentified sp. 2), and unidentified species of cow bug, planthoppers, flatid planthopper and spittle bug. The biting and chewing pests recorded were leaf twisting weevil (Apoderus sp.), flower beetle (Popillia complanata Newman, Gametis versicolor (Fabricius)), flea beetle (Luperomorpha vittatta Duvivier), leaf cutting bee (Megachile sp.), common hedge blue (Acytolepis puspa (Horsfield)), brown tussock moth (Olene mendosa Hubner), tussock moth (Arna bipunctapex Hampson), tobacco cutworm (Spodoptera litura (Fabricius)), and black looper (Hyposidra talaca (Walker)). Leaf rollers, hairy caterpillar, slug caterpillar, grass hoppers, ash weevil, bag worms and slug pests documented during the study. A total of thirteen species of natural enemies associated with pests of rose were identified. Six species of spiders, Oxyopes birmanicus Thorell, Oxyopes javanus Thorell, Oxyopes shwetha Tikader, Stenaelurillus sp., Camaricus formosus Thorell, and Thomisus sp., were identified, and they were the predominant predators in the rose ecosystem. This was followed by four species of coccinellids (Pseudaspidimerus trinotatus (Thunberg), Rodolia sp., Scymnus sp., and Sticholotidini beetle), two species of preying mantids, Odontomantis pulchra Olivier and Hestiasula brunneriana Saussure, and a neuropteran insect. Spiromesifen 22.9 % SC @ 96 g a.i. ha -1 was the best treatment recorded for R. syriacus and S. dorsalis with highest reduction of 94.90 % and 98.1 % respectively in thrips population at 7 DAS. At 14 DAS, spiromesifen 22.9 % SC @ 96 g a.i. ha -1 was significantly superior to dimethoate 30 % EC @ 400 g a.i. ha-1 in reducing the population of S. dorsalis, while the effect of both treatments were statistically on par for R. syriacus. Least effective treatment was HMO @ 25 mL L-1 for both thrips and was on par with the effect of talc based formulation of L. lecanii @ 20 g L-1. Spiromesifen 22.9 % SC @ 96 g a.i. ha -1 treated plants showed lowest leaf damage (18.86 %) for R. syriacus and lowest flower (6.29 %) and flower bud (6.21 %) damage for S. dorsalis and the effect was on par with dimethoate 30 % EC @ 400 g a.i. ha-1 at 14 DAS. Lowest reduction (10.67 %) in spider population was 101 recorded in talc based formulation of L. lecanii @ 20 g L-1 treated plants which was statistically on par with spiromesifen 22.9 % SC @ 96 g a.i. ha -1, untreated plants and HMO @ 25mL L-1 treated plants. Flubendiamide 39.35 % SC @ 48g a.i. ha -1 was the effective treatment recorded with significantly higher percentage reduction in population of O. mendosa at 14 DAS followed by malathion 50 % EC @ 500 g a.i. ha -1 (85.91 %). Results of effect of different treatments on extent of leaf damage in O. mendosa infested plants showed lowest value in flubendiamide 39.35 % SC @ 48 g a.i. ha -1 treated plants and was on par with malathion 50 % EC @ 48 g a.i. ha -1. HMO @ 25mL L-1 was least effective in managing O. mendosa with mean percentage damage of 34.44. Lowest percentage reduction (8.33) in spider population was recorded in talc based formulation B. bassiana @ 20 g L-1 treated plants and was on par with untreated plants and NSKE 5%. A total of 42 species of pests infesting rose were recorded of which five are new records in rose from Kerala. Thirteen species of natural enemies associated with pests of rose were also recorded. Spiromesifen 22.9% SC @ 96 g a.i. ha -1 was the effective treatment for the management of S. dorsalis and R. syriacus and flubendiamide 39.35 % SC @ 48 g a.i. ha -1 was found effective in reducing Olene mendosa population in rose. 102