Author: Edward J. Brooks
Publisher:
ISBN:
Category : Amino acids
Languages : en
Pages : 87

Get Book Here

Book Description

Author: Kenneth E. Frick
Publisher: Forgotten Books
ISBN: 9780260780096
Category :
Languages : en
Pages : 42

Get Book Here

Book Description
Excerpt from Agents for Biological Control of Purple Nutsedge, Cyperus Rotundus L: The Genus Bactra Stephens (Lepidoptera; Tortricidae; Olethreutinae) As a Major Source, With Emphasis on the Biology and Potential Use of Bactra Verutana Zeller Among the more widespread weeds in the world are two perennial herbs that propagate primarily by means of underground tubers. These plants are in the sedge family, Cyperaceae, and are purple nutsedge, Cyperus rotundus L., and yellow nutsedge, C. Esculentus L. Because these weeds are difficult to control, Holm et al. (1977) rated purple nutsedge as the world's worst weed and yellow nutsedge as the 16th worst. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.

Author: Christopher Kheng Hoe Teo
Publisher:
ISBN:
Category : Nutgrass
Languages : en
Pages : 7

Get Book Here

Book Description

Author: Kenneth Eugene Frick
Publisher:
ISBN:
Category : Cyperaceae
Languages : en
Pages : 36

Get Book Here

Book Description

Author: Richard Lyle Chase
Publisher:
ISBN:
Category : Nutgrass
Languages : en
Pages : 104

Get Book Here

Book Description

Author: Michael W. Edenfield
Publisher:
ISBN:
Category : Herbicides
Languages : en
Pages : 278

Get Book Here

Book Description

Author: James L. Faubion
Publisher:
ISBN:
Category : Nutgrass
Languages : en
Pages : 112

Get Book Here

Book Description

Author: A. A. L. Amerasinghe
Publisher:
ISBN:
Category : Nutgrass
Languages : en
Pages : 310

Get Book Here

Book Description
Purple nutsedge [Cyperus rotundas L.) has been recognized as one of the most troublesome perennial weeds of agricultural lands in tropical and some temperate regions. This research sought to determine the effects of timing of herbicides, shading, and soil moisture on plant population growth and tuber production of purple nutsedge through field and greenhouse experiments. The results of these experiments were used to validate a purple nutsedge population matrix model constructed with observed and reported data. Purple nutsedge control options were evaluated with model simulations. Glyphosate reduced shoot number, tuber number, and tuber viability of purple nutsedge, and the herbicide efficacy was higher when applied from 2 to 4 weeks after shoot emergence as compared to the first 2-week growth period. The more effective period for the herbicide coincided with the tuber initiation phase of purple nutsedge growth. Metolachlor caused only temporary suppression of purple nutsedsge. Sunlight intensity by 30%, 47%, 63%, and 90% caused in successively greater reductions in shoot number, tuber number, leaf area, and total dry weight of purple nutsedge. Shading decreased partitioning of plant biomass into tubers and increased partitioning into leaves. These responses remained essentially the same irrespective of timing of shading from early emergence through the first 4 weeks of plant growth. Depletion of available soil moisture from 25% to 75% also reduced the number and dry weights of shoots and tubers produced. However, proportional biomass allocation to shoots, leaves, and tubers and relative growth and net assimilation rates remained unaltered with soil moisture depletion, suggesting that purple nutsedge is fairly well adapted to low soil moisture levels. The importance of intraspecific competition on population regulation of purple nutsedge was evident from model simulations. Model predictions of maximum population size closely agreed with reported plant and tuber densities of purple nutsedge. Model simulations of proportional changes in population size of purple nutsedge, as influenced by soil moisture depletion or shading, also closely followed the field results. Model simulations indicated that seasonal application of herbicides resulting in 90% shoot kill will provide a successful level of control and that herbicide efficiency will be higher when shoots are killed during the second to fourth week of the growing period than from earlier applications. However, model simulations showed that a better strategy than using a highly effective, short duration herbicide is to provide a moderate level of purple nutsedge control extending through the growing season.

Author: Mark Andrew Czarnota
Publisher:
ISBN:
Category :
Languages : en
Pages : 116

Get Book Here

Book Description

Author: Leon Shelton Warren
Publisher:
ISBN:
Category : Crop rotation
Languages : en
Pages : 142

Get Book Here

Book Description