Author: Lindsey K. Gastler
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Grain sorghum (Sorghum bicolor L.) is an important crop to Kansas agriculture, and Palmer amaranth (Amaranthus palmeri S. Wats.) is considered the most troublesome weed in grain sorghum. In 2019, field experiments were conducted near Manhattan and Hutchinson, Kansas to determine the influence of grain sorghum planting dates and Palmer amaranth emergence timings on competitive outcomes. Grain sorghum was planted on June 3 and July 1 at Manhattan and May 17 and June 17 at Hutchinson. Natural populations of Palmer amaranth were established at an early and late emergence timing relative to crop planting along with a weed-free treatment. Palmer amaranth was thinned and maintained at a target population of 4 plants m−1 of row. The growth stage and height of grain sorghum and Palmer amaranth were recorded weekly. Biweekly up to grain sorghum flag-leaf stage, two grain sorghum and two Palmer amaranth plants plot−1 were harvested to measure leaf area and biomass. Grain sorghum was harvested to measure yield and seed weight. Late planted grain sorghum accumulated height, leaf area, and biomass more quickly than early planted grain sorghum on a time scale of days after planting (DAP) at both locations. On a scale of growing degree units (GDU), grain sorghum leaf area and biomass accumulation at Manhattan were similar across planting dates, while the late planting accumulated more height. In Hutchinson, grain sorghum leaf area accumulation was similar across plantings, while the late planting accumulated height and biomass more quickly on a GDU scale. Palmer amaranth density in both sites were less than desired and inconsistent, therefore, it was impossible to test the effects of Palmer amaranth emergence timing. In Manhattan, grain yields were similar across treatments, excluding the treatment with the highest Palmer amaranth density (1.5 plants m−1 of row), and seed weight was greater in the early planting than the late. In Hutchinson, grain sorghum yield was 37% less in the early planting than the late planting, due to poor crop establishment in cool soil temperatures after planting, and poor pollination and grain fill during hot and dry conditions. Later planted grain sorghum grew faster than early planted grain sorghum, thus was more competitive against weed competition in early growth stages. This research demonstrated a potential tactic that a producer could implement to enhance early season competitiveness of grain sorghum against Palmer amaranth.
Author: Jerry Wayne Moore
Publisher:
ISBN:
Category :
Languages : en
Pages : 118
Get Book Here
Book Description
Author: Admasu Melake-Berhan
Publisher:
ISBN:
Category : Fungi in agriculture
Languages : en
Pages : 214
Get Book Here
Book Description
Author: Ivan Bernardo Cuvaca
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Palmer amaranth is a major threat to many cropping systems in the USA. As a result of selection, Palmer amaranth has evolved resistance to at least six herbicide modes of action including microtubule-, 5-enolpyruvylshikimate-3-phosphate synthase-, acetolactate synthase-, photosystem II-, hydroxyphenylpyruvate dioxygenase-, and protoporphyrinogen oxidase- inhibitors. Dicamba is effective for Palmer amaranth control; however, extensive use of this herbicide increases the likelihood of evolution of resistance to dicamba. The overall objective of this dissertation was to investigate the physiological basis of interaction of herbicides with different modes of action in Palmer amaranth control and evaluate use of integrated approaches to manage Palmer amaranth in field conditions. The specific objectives were to: 1) evaluate the effect of plant height on dicamba efficacy to control Palmer amaranth; 2) investigate the mechanism of resistance to glyphosate in a Palmer amaranth accession from Kansas, and evaluate efficacy of glyphosate and dicamba tank-mix to control this accession; 3) investigate the physiological basis of glyphosate and dicamba interaction in tank-mix to control Palmer amaranth; 4) determine the efficacy of reduced dicamba use on Palmer amaranth control in irrigated corn production; and 5) investigate grain sorghum and Palmer amaranth growth and reproductive attributes in response to sorghum density and nitrogen rate under irrigated conditions. All experiments were repeated and appropriate statistical tests were used for data analyses. The results indicate: a) increased absorption and translocation of dicamba contribute to increased efficacy to control Palmer amaranth at early growth stage; b) tank mixing glyphosate and dicamba had a synergistic effect on Palmer amaranth control; c) rapid absorption of dicamba and increased translocation of glyphosate resulted in increased Palmer amaranth control when applied in combination; d) there is an opportunity to maintain grain yield while effectively controlling Palmer amaranth in irrigated corn with the integration of increased corn plant population density and reduced dicamba application and e) integrating sorghum plant population and nitrogen did not suppress Palmer amaranth in irrigated sorghum, although sorghum grain yield was maintained. The outcome of this dissertation provides several strategies to improve control of Palmer amaranth.
Author:
Publisher:
ISBN:
Category : Herbicides
Languages : en
Pages : 516
Get Book Here
Book Description
Author: National Academies of Sciences, Engineering, and Medicine
Publisher: National Academies Press
ISBN: 0309437385
Category : Science
Languages : en
Pages : 607
Get Book Here
Book Description
Genetically engineered (GE) crops were first introduced commercially in the 1990s. After two decades of production, some groups and individuals remain critical of the technology based on their concerns about possible adverse effects on human health, the environment, and ethical considerations. At the same time, others are concerned that the technology is not reaching its potential to improve human health and the environment because of stringent regulations and reduced public funding to develop products offering more benefits to society. While the debate about these and other questions related to the genetic engineering techniques of the first 20 years goes on, emerging genetic-engineering technologies are adding new complexities to the conversation. Genetically Engineered Crops builds on previous related Academies reports published between 1987 and 2010 by undertaking a retrospective examination of the purported positive and adverse effects of GE crops and to anticipate what emerging genetic-engineering technologies hold for the future. This report indicates where there are uncertainties about the economic, agronomic, health, safety, or other impacts of GE crops and food, and makes recommendations to fill gaps in safety assessments, increase regulatory clarity, and improve innovations in and access to GE technology.
Author: Andrew Price
Publisher: BoD – Books on Demand
ISBN: 9535122185
Category : Technology & Engineering
Languages : en
Pages : 184
Get Book Here
Book Description
Herbicides are one of the most widely used groups of pesticides worldwide for controlling weedy species in agricultural and non-crop settings. Due to the extensive use of herbicides and their value in weed management, herbicide research remains crucial for ensuring continued effective use of herbicides. Presently, a wide range of research continues to focus on improved herbicide use and weed biology. The authors of Herbicides, Agronomic Crops and Weed Biology cover multiple topics concerning current valuable herbicide research.
Author: Andy Clark
Publisher: DIANE Publishing
ISBN: 1437903797
Category : Technology & Engineering
Languages : en
Pages : 248
Get Book Here
Book Description
Cover crops slow erosion, improve soil, smother weeds, enhance nutrient and moisture availability, help control many pests and bring a host of other benefits to your farm. At the same time, they can reduce costs, increase profits and even create new sources of income. You¿ll reap dividends on your cover crop investments for years, since their benefits accumulate over the long term. This book will help you find which ones are right for you. Captures farmer and other research results from the past ten years. The authors verified the info. from the 2nd ed., added new results and updated farmer profiles and research data, and added 2 chap. Includes maps and charts, detailed narratives about individual cover crop species, and chap. about aspects of cover cropping.
Author: Bhagirath Chauhan
Publisher: Elsevier
ISBN: 0128229357
Category : Science
Languages : en
Pages : 433
Get Book Here
Book Description
Weeds are the main biological constraint to crop production throughout the year. Uncontrolled weeds could cause 100% yield loss. In Australia, the overall cost of weeds to Australian grain growers was estimated at AU$ 3.3 billion annually. In terms of yield losses, weeds amounted to 2.7 million tonnes of grains at a national level. In the USA, weeds cost US$ 33 billion in lost crop production annually. In India, these costs were estimated to be much higher (US$ 11 billion). These studies from different economies suggest that weeds cause substantial yield and economic loss. Biology and Management of Problematic Weed Species details the biology of key weed species, providing vital information on seed germination and production, as well as factors affecting weed growth. These species include Chenopodium album, Chloris truncata and C. virgate, Conyza bonariensis and C. canadensis, Cyperus rotundus, and many more. This information is crucial for researchers and growers to develop integrated weed management (IWM) strategies. Written by leading experts across the globe, this book is an essential read to plant biologists and ecologists, crop scientists, and students and researchers interested in weed science. - Provides detailed information on the biology of different key weed species - Covers weed seed germination and emergence - Presents the factors affecting weed growth and seed production
Author: Robert L. Zimdahl
Publisher: John Wiley & Sons
ISBN: 0470290102
Category : Technology & Engineering
Languages : en
Pages : 235
Get Book Here
Book Description
For the past 20 years, the first edition of this text has been widely cited as authoritative academic reference. The latest edition continues the tradition set by the original book, and covers weed science research that has been published since 1980. This book aims to reduce the instance of research duplication—saving scientists and supporting institutions time and money. Not only does the second edition of Weed Crop Competition review, summarize, and combine current research; it critiques the research as well. This text has the potential to accelerate advancements in weed crop competition, which remains an important factor that affects crop yields. Scientists in foreign countries where access to literature is often limited or nonexistent, will find the information in this text invaluable. Weed scientists, crop scientists, plant ecologists, sustainable agriculturists, and organic agriculturists will be well-pleased with this long overdue and much needed new editionWeed Crop Competition provides a unique reference that reviews, summarises and synthesizes the literature published concerning research on this topic. The first edition has been one of the most frequently cited sources in weed science for the past 20 years. The second edition covers the significant body of literature that has been published since 1980. Originally intended to survey existing research, the intent of the book is to reduce the instance of research duplication, thus saving scientists and their institutions time and money, and expediting advancements in weed crop competition, an important factor affecting crop yields. Scientists in foreign countries where access to the literature is often limited or non-existent, find the information an invaluable resource. This long overdue and much needed new edition rejuvenates the tradition set by the original book.
