The Influence of the Extract of Some Crops and Soil Residues on Germination and Growth

Abstract

ABSTR.ACT. Si-r plant species r,vere germinated in sancl wetted with water extracts of rlssues .,1 hve herd crops and three soils. Deionized water w-as used as a check.-l-he-stud1 ivas conducted rrsing srandard ieed germination te.nniqrer.

Allelopathic Effects of Sunflower Residue on Growth of Rice and Sbsequent Wheat Crop

“…Oleszek and Jurzysta (1987) reported wheat seed germination and seedling growth were suppressed by water and alcohol extracts of alfalfa (Medicago sativa L.) roots. This phenomenon has also been reported in other crops like corn (Zea mays L.) and oat (Avena sativa L.) (Nielsen et al, 1960;Al-Tawaha and Odat, 2010), rice (Oryza sativa L.) (Hisashi, 2004;Javaid et al, 2008) and cotton (Gossypium hirsutum L.) (Ioannis et al, 2005). The allelopathic effects are selective, depending upon the concentrations and residue type, either inhibitory or stimulatory to the growth of companion or subsequent crops or weeds (Mushtaq et al, 2003;Cheema et al, 2004;Javaid et al, 2007).…”

Biological activity and chemical isolation of root saponins of six cultivars of alfalfa (Medicago sativa L.)

“…Alfalfa produces allelopathic saponins, which, as residue in soil, may be a major cause of the reduced yields of subsequent crops (Goplen and Webster, 1969;Guenzi et al, 1964;Hall and Henderlong, 1984;Kehr et al, 1983;Klein and Miller, 1980;Leshem and Levin, 1978;McEIgunn and Hemrichs, 1970;Miller et al, 1983;Nielsen et al, 1960;Oleszek and Jurzysta, 1987;Oleszek et al, 1990a;Pedersen and Wang, 1971). The detailed chemical structure of most saponins is unknown, and as many as 30 compounds with similar properties are present in alfalfa parts.…”

Alfalfa saponins — the allelopathic agents

“…Toxic substances from old stems, crowns and roots of alfalfa may be detrimental to the establishment of new seedlings. Alfalfa autotoxicity for seedling growth was reported in laboratory and greenhouse studies (Nielsen et at., 1960;McElgunn and Heinricks, 1970;Klein and Miller, 1980;Jensen, 1984). An autotoxic agent was reported to be present in fresh alfalfa leaves, stems, crowns, and in dry hay, old roots, soil and soil residues.…”