Anaerobic seed germination for the habitat segregation in Echinochloa weeds

• Published in: Ikushugaku zasshi Vol. 39; no. 2; pp. 159 - 168
• Main Authors: Yamasue, Y. (Kyoto Univ. (Japan). Coll. of Agriculture), Asai, Y, Ueki, K, Kusanagi, T
• Format: Journal Article
• Language: English
• Published: Tokyo Japanese Society of Breeding 01.06.1989; Nihon Ikushu Gakkai, c/o Tokyo Daigaku Nogakubu
• Subjects: ANAEROBIOSE; ANAEROBIOSIS; Biological and medical sciences; ECHINOCHLOA; flooding resistance; Fundamental and applied biological sciences. Psychology; Generalities, botany, ecology, damages, economic importance; GERMINACION; GERMINATION; HABITAT; HABITATS; HABITOS DE CRECIMIENTO; MALEZAS; MAUVAISE HERBE; Parasitic plants. Weeds; Phytopathology. Animal pests. Plant and forest protection; PLANT HABIT; PORT DE LA PLANTE; WEEDS; Anaerobiosis; Monocotyledones; Weed; Echinochloa crusgalli; Germination; Japan; Environmental factor; Flood; Asia; Gramineae; Seed; Angiospermae; Echinochloa; Spermatophyta; Paddy field
• ISSN: 0536-3683; 2185-291X
• DOI: 10.1270/jsbbs1951.39.159

To verify the habitat segregation of Echinochloa weeds into flooded rice paddies and unflooded uplands, about 200 accessions of the weeds were field-collected at various locations in Kyoto and Shiga Prefectures. Sixty six of the 68 accessions of E, oryzicola and E, crusgalli var. formosensis in total were present in flooded rice paddies, while 56 of the 60 accessions of E. crus-galli var. praticola at habitats of upland conditions. E. crus-galli var. crus-galli showed no specific habitats and distributed throughout the habitats we surveyed. In pot experiments with one strain each of the weeds, either E. oryzicola or E. crus-galli var. formosensis was little affected in seed germination and seedling growih under 10 and 15cm flooding and the seeds germinated even under nitrogen. However, no seeds of E. crus-galli var. praticola virtually germinated either under flooding at 5 cm depth or nitrogen atomosphere and the seedlings stunted in height when the post-germinating seeds were sowed under flooding. Seed germination and seedling growth of E. crus-galli var. crus-galli were also adversely affected under flooding and nitrogen atmosphere, but not as greatly as those of E. crus-galli var. praticola. These results and the Km values of seeds in oxygen uptake suggested that the incapability of anaerobic germination constitute the primary physiological barrier(s) against its invation into flooded rice.