期刊
CROP & PASTURE SCIENCE
卷 70, 期 4, 页码 367-372出版社
CSIRO PUBLISHING
DOI: 10.1071/CP18444
关键词
conservation tillage; fitness penalty; germination ecology; glyphosate resistance; salt stress; seed production
Echinochloa colona L. (Link) (awnless barnyard grass) is one of the top three most problematic weeds of summer crops in Australia. This weed has evolved resistance to glyphosate. A study was conducted to evaluate the effect of environmental factors on the germination and seedling emergence of a glyphosate-resistant (GR) and a glyphosate-susceptible (GS) biotype of E. colona. The two biotypes had similar germination and emergence responses to light and temperature conditions, water stress, solution pH, sorghum residue cover and seed burial depth. Light stimulated germination more than dark conditions, and seeds germinated at a wide range of alternating day/night temperatures, from 20 degrees C/10 degrees C to 35 degrees C/25 degrees C, whereas no seeds germinated at 15 degrees C/5 degrees C. These results suggest that E. colona can emerge in spring, summer and autumn in Queensland. The sodium chloride concentration required to inhibit 50% germination was greater for the GR biotype (209 mm) than the GS biotype (174 mm). Seed germination was not affected by pH in the range 4-10. Water stress reduced germination by 50% at an osmotic potential of -0.44 MPa. In a shade-house study, retention of sorghum residue cover on the soil surface reduced the seedling emergence of E. colona. Emergence was 70% in the absence of crop residue, whereas a residue amount of 8 t ha(-1) reduced emergence to 47%. Emergence was greatest for seeds placed on the soil surface and declined linearly with increasing burial depth; no seedlings emerged from 8 cm depth. The GR biotype had higher germination than the GS biotype under high sodium chloride concentrations; therefore, this biotype may be highly competitive with crops under highly saline conditions. Because germination was high on the soil surface and was stimulated by light, this weed will remain problematic under no-till farming systems in Australia.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据