Factors Limiting the Distribution of Cogongrass, Imperata cylindrica, and Torpedograss, Panicum repens

• Published in: Weed science Vol. 36; no. 5; pp. 577 - 582
• Main Authors: Wilcut, John W., Dute, Roland R., Truelove, Bryan, Davis, Donald E.
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 01-09-1988; Weed Science Society of America
• Subjects: Agricultural soils; Analysis of variance; ANATOMIA DE LA PLANTA; ANATOMIE VEGETALE; Biological and medical sciences; COMPETENCIA BIOLOGICA; COMPETITION BIOLOGIQUE; Degrees of freedom; DISTRIBUCION NATURAL; DISTRIBUTION NATURELLE; Fundamental and applied biological sciences. Psychology; Generalities, botany, ecology, damages, economic importance; GERMINACION; GERMINATION; Grasses; IMPERATA CYLINDRICA; MALEZAS; MAUVAISE HERBE; PANICUM REPENS; Parasitic plants. Weeds; Phytopathology. Animal pests. Plant and forest protection; Plants; PRODUCCION DE SEMILLAS; PRODUCTION DE SEMENCES; RHIZOME; Rhizomes; RIZOMAS; Seeds; Soil pH; Weed Biology and Ecology; Weeds; Cogongrass, Imperata cylindrica (L.) Beauv. #3 IMPCY; PANRE; temperature; Sorghum halepense; SORHA; Replacement series; IMPCY; johnsongrass, Sorghum halepense (L.) Pers. # SORHA; torpedograss, Panicum repens L. # PANRE; Tolerance; Temperature; Weed; Geographic distribution; Limiting factor
• ISSN: 0043-1745; 1550-2759
• DOI: 10.1017/S0043174500075433

Greenhouse, growth chamber, and laboratory studies were conducted to determine anatomical and morphological characteristics and cultural practices limiting the distribution of cogongrass, torpedograss, and johnsongrass in the United States. Cogongrass did not produce axillary buds along most of the rhizome nor regenerate when apical six-node-long rhizome segments were buried deeper than 8 cm. Both torpedograss and johnsongrass produced axillary buds along the entire lengths of their rhizomes. Torpedograss shoot emergence decreased at burial depths between 8 and 16 cm. Shoot emergence from johnsongrass rhizomes was not affected by burial as deep as 16 cm. Rhizomes of all three species were tolerant of desiccation. Cogongrass grew better in soil at pH 4.7 than in soil at pH 6.7, whereas torpedograss and johnsongrass grew equally well in either pH. It is postulated that cogongrass spread is limited by lack of axillary bud formation on most of the rhizome and the inability of rhizomes to send up new shoots if buried deeper than 8 cm. These factors could account for the intolerance of cogongrass to cultivation. Torpedograss appears to spread only vegetatively due to the lack of viable seed production.