Weed control in rose-scented geranium (Pelargonium spp).
Abstract: Field investigations were carried out during 1999 and 2000 to identify effective chemical/ cultural methods of weed control in rose-scented geranium (Pelargonium spp). The treatments comprised pre-emergence applications of oxyfluorfen (0.15, 0.20 and 0.25 kg AI ha(-1)) and pendimethalin (0.50, 0.75 and 1.00kg AI ha(-1)), successive hand weeding, hoeing and mulching using spent of lemon grass (at 5 tonnes ha(-1)) 45 days after planting (DAP), three hand-weedings 30, 60 and 90 DAP, weed-free (frequent manual weeding) and weedy control. Broad-leaf weeds were more predominant than grass and sedge weeds, accounting for 85.8% weed density and 93.0% weed dry weight in 1999 and 77.2% weed density and 93.9% weed dry weight in 2000. Unrestricted weed growth significantly reduced geranium oil yield, by 61.6% and 70.6% in 1999 and 2000, respectively. Pre-emergence application of pendimethalin (0.75-1.00 kgAI ha(-1)) or oxyfluorfen (0.25 kg AI ha(-1)), successive hand-weeding, hoeing and mulching and three hand-weedings were highly effective in reducing weed density and dry weight and gave oil yield comparable to the weed-free check. Application of oxyfluorfen (0.15 or 0.20 kg AI ha(-1)) and pendimethalin (0.50 kg AI ha(-1)) were less effective in controlling the weed species in geranium. None of the herbicides impaired the quality of rose-scented geranium oil measured in terms of citronellol and geraniol content.
Kothari
Sushil K
SK
Central Institute of Medicinal & Aromatic Plants, Field Station, Boduppal Uppal (PO), Hyderabad-500 039, India. cimaphyd@rediffmail.com
Singh
Chandra P
CP
Singh
Kamla
K
D000080462:Acyclic Monoterpenes; D035722:Aizoaceae / Q000187:drug effects; D027721:Amaranthus / Q000187:drug effects; D000814:Aniline Compounds / Q000008:administration & dosage / Q000737:chemistry / Q000633:toxicity; D027462:Chenopodium / Q000187:drug effects; D029786:Cyperus / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D055768:Halogenated Diphenyl Ethers; D006540:Herbicides / Q000008:administration & dosage / Q000737:chemistry / Q000633:toxicity*; D029903:Melilotus / Q000187:drug effects; D039821:Monoterpenes / Q000378:metabolism; D031316:Pelargonium / Q000254:growth & development* / Q000378:metabolism; D010647:Phenyl Ethers / Q000008:administration & dosage / Q000737:chemistry / Q000633:toxicity; D010938:Plant Oils / Q000378:metabolism*; D010944:Plants / Q000187:drug effects*; D006109:Poaceae / Q000187:drug effects; D013729:Terpenes / Q000378:metabolism
D000080462:Acyclic Monoterpenes; D000814:Aniline Compounds; D055768:Halogenated Diphenyl Ethers; D006540:Herbicides; D039821:Monoterpenes; D010647:Phenyl Ethers; D010938:Plant Oils; D013729:Terpenes; C016027:oxyfluorofen; C007836:geraniol; C007078:citronellol; C030856:pendimethalin