WEDELIA GLAUCA (ORTEGA)
(ASTERACEAE): POISONOUS WEED
INTRODUCTION
Wedelia is a flowering plant genus in the sunflower family. They are one of the genera commonly called "creeping-oxeyes".
Wedelia glauca (Ortega) O. Hofmm ex Hicken (Asteraceae), the species was native of Chile, South America and widely spread in Argentina, South Brazil and Uruguay. It is considered a poisonous weed and its toxicity is due to presence of hepatotoxic terpionod, atractyloside. Further, it is commonly known as, Agricultural plague in Argentina. So far India is concern this species was firstly recorded from Tiruppur, Coimbatore, from Tamil Nadu of South India (Aloke Bhattacharya et al., 1995) & also reported in the field of Sugarcane crop from Urun-Islampur of Walwa taluka of Sangli district of Maharashtra (Salunkhe et al., 2002). Plant collection made during floristic survey of Walwa taluka in Sangli district of Maharashtra, author came across an interesting weed population of Wedelia not only in sugarcane crop but also occurs in the field of Chili, Tomato and Wheat crop from Urun-Islampur area, taluka place of Walwa near about 1.5 Km. from Islampur city. Its occurrence in above crops from Sangli district forms new distributional areas and spread in variety of crops and becomes naturalized in Maharashtra. It is recent introduction to this region, possibly through Cucumis or Tomato seeds. A detailed field observations, description and illustration are provided here to facilitate its easy identification for Botanist, veterinarians and Agriculturalist. Examined specimens deposited in the Herbarium, Department of Botany, K.R.P. Kanya Mahavidyalaya, Islampur, District Sangli.
RESULTS AND DISCUSSIONS
Field Observations: Wedelia is well growing as a weed in the various crops including sugarcane, Wheat,
Tomato, Chili and Brinjal. It is spread nearly one and half square kilometer field area. It is considered as
poisonous to domestic animals and human and showing toxic effect if it consumes the sheep, goat, cattle,and cows.
Intoxication by present weed, cattle and cows as well as grazing sheep and goat are found to be sudden
death after eating. Generally, the foetus gets aborted a few hours after consumption even if it accidently
mixed with other forage. The growth and density of the crop plants becomes reduced, stunted in highly
affected area. It is also found that, the total yield of crop is reduced & the fruit smell of tomato and brinjal
are badly affected so market value is lower down. There is no anyone association of other weed in the
field even the Cynadon is common weed in black soil in this region.
Field Observations: Wedelia is well growing as a weed in the various crops including sugarcane, Wheat,
Tomato, Chili and Brinjal. It is spread nearly one and half square kilometer field area. It is considered as
poisonous to domestic animals and human and showing toxic effect if it consumes the sheep, goat, cattle,and cows.
Intoxication by present weed, cattle and cows as well as grazing sheep and goat are found to be sudden
death after eating. Generally, the foetus gets aborted a few hours after consumption even if it accidently
mixed with other forage. The growth and density of the crop plants becomes reduced, stunted in highly
affected area. It is also found that, the total yield of crop is reduced & the fruit smell of tomato and brinjal
are badly affected so market value is lower down. There is no anyone association of other weed in the
field even the Cynadon is common weed in black soil in this region.
DESCRIPTION
Annual or perennial stoloniferous herbs; about 18-30 cm. in height. Stem erect, glabrous, sparsely hirsute
with longitudinal striations. Leaves simple, opposite, sessile about 8-11 cm. oblong-lanceolate, glabrous
to scabrous with minutely hairs; hairs gland based apprising, base narrow with 2-3 or often 2 dentate teeth
and acuminate apex, entire margin towards apex, slightly dentate at lower side. Flowers in pedunculate
solitary, terminal or axillary heads; peduncle about 1.5-3 cm. long. Heads hemispherical to companulate
about 1 -1.8 x .7-1.5 cm. Involucral bracts 2-3 seriate; inner is membranous and outer is leafy. Receptacle
flat or convex, scales prominent. Ray florets carpellate with one row, fertile or sometimes sterile, ligulate.
About .8-1.5 cm. long, limb elongate. Corolla yellow. Disc florets bisexual, tubular, 5-lobed. Anthers
auriculata or truncate base, ovate or slightly acute apex and exserted. Style branched, filiform, hairy
outside. Achenes about .4-.6 cm. obovoid, compressed, angled and glabrous, flattened in ray florets. Disc
usually hairy, 4-angled, compressed and thick. Papus short or lacerate scales with 2 minute awns, awns
absent in ray florets.
Annual or perennial stoloniferous herbs; about 18-30 cm. in height. Stem erect, glabrous, sparsely hirsute
with longitudinal striations. Leaves simple, opposite, sessile about 8-11 cm. oblong-lanceolate, glabrous
to scabrous with minutely hairs; hairs gland based apprising, base narrow with 2-3 or often 2 dentate teeth
and acuminate apex, entire margin towards apex, slightly dentate at lower side. Flowers in pedunculate
solitary, terminal or axillary heads; peduncle about 1.5-3 cm. long. Heads hemispherical to companulate
about 1 -1.8 x .7-1.5 cm. Involucral bracts 2-3 seriate; inner is membranous and outer is leafy. Receptacle
flat or convex, scales prominent. Ray florets carpellate with one row, fertile or sometimes sterile, ligulate.
About .8-1.5 cm. long, limb elongate. Corolla yellow. Disc florets bisexual, tubular, 5-lobed. Anthers
auriculata or truncate base, ovate or slightly acute apex and exserted. Style branched, filiform, hairy
outside. Achenes about .4-.6 cm. obovoid, compressed, angled and glabrous, flattened in ray florets. Disc
usually hairy, 4-angled, compressed and thick. Papus short or lacerate scales with 2 minute awns, awns
absent in ray florets.
Conclusion
Present study pertains present status of poisonous weed & shown that it is badly affected on crop growth,
yield and vegetable market. Present weed adversely affects on the socio-economic status of farmers in this
region. It needs wide publicity and documentation for farmers veterinarians and agriculturist to find out
the proper solution on weed eradication. Further, it is helpful for correct identification of weed.
