Propagation Of Orchids

OTHER METHODS

Cultural methods like subjecting the plants to a temperature regime of 35-37°C for 9 weeks was reported to eliminate 96% of cyrnbidium ring spot vu. horn infected Nantiation slatelandii (cf. Zaidi at al., 2001). Inheritance of Dendrobisin floral necrosis caused by Cy MV was studied by Kobayashi and Kamarnoto (1989) and observed that crosses between susceptible parents produced susceptible progeny, whereaa crosses between resistant parents produced resistant progeny. Kuehnle (19%) discussed control and eradication of virus in Dendrabinm by hybridization, tissue culture and genetic engineering. A genetic alternative androgenosis coupled with chromosome doubling by colchicine treatment was reported as effective for ridding amphidiplord of viruses.

A BRIEF REVIEW ON INSECT PESTS OF ORCHIDS

Several workers have studied insect pests of orchids in different parts of the world, In the following section, reports on insect pests of orchids are briefly mentioned.

The females of Oichromothrips cortetti damaging flowers of variety of Vanda orchids was observed (Anonymous, 1971).

Harmon (1979) reported Ansearrum Scale, Conehaspisangraeri Cockevell, tube causing severe damage on the stems and leaves of orchid in Florida.

Timmerman and Vrie (1982) suggested that Thrips raised on orchids could be controlled by (0 misting 100 ml delta-methrin, 40-50 ml permethrin or 100-150 ml pirimiphosmethyl per 1000 rri; (ii) spraying with 2550 g or 25-50 ml perrnethrin or 50 ml deltamethrin, 100 g proposur, 508 acepha le or 100 ml pirimiphosmethyl, and (iii) dusting with 300 g propoxur or 200-3050 parathion.

Black twig borer, Xylosandnm compact. (Eichhoff) 0 feed on orchids was reported by Dixon and Woodruff (1983). They recommended use of chloropyrif. at preliminary stage.

Mau (1983) reported orchid weevil, Orallidophilus Merriam. in Haw.. He observed that the weevils laid egg; in the cavities formed by adull feeding, larvae mined pseudobulbs, completed pupation inside mine.

Lanandin (1983) reported a new species of scale, rtslerolecanium rossellae on orchids in l'hilippines.

I lartley at al. (19E4) suggested to include two biological control agents Eniarsia formosa and Phytusendm persimilis in 1PM for Cymbidi fon orchids.

Pettersson (1984) recorded the presence of Brevipalpas oncidli Baker and Prisfiphara alnitera Mg. on orchids for the first time in Sweden.

Tyraphagus !angler, a polyphagos mite, was recorded to cause flower damage in Cyranidiurn in Italy by Ciampolini at al. (1985).