Management Strategies for Herbicide-resistant Weed Populations in Australian Dryland Crop Production Systems

2007 ◽  
Vol 21 (2) ◽  
pp. 332-338 ◽  
Author(s):  
Michael J. Walsh ◽  
Stephen B. Powles
2021 ◽  
pp. 1-25
Author(s):  
Mandy Bish ◽  
Brian Dintelmann ◽  
Eric Oseland ◽  
Jacob Vaughn ◽  
Kevin Bradley

Abstract The evolution of herbicide-resistant weeds has resulted in the necessity to integrate non-chemical control methods with chemicals for effective management in crop production systems. In soybean, control of the pigweed species, particularly herbicide-resistant waterhemp and Palmer amaranth, have become predominant concerns. Cereal rye planted as a winter cover crop can effectively suppress early-season weed emergence in soybean, including waterhemp, when planted at a rate of 123 kg ha−1. The objectives of this study were to determine the effects of different cereal rye seeding rates (0, 34, 56, 79, 110, and 123 kg ha−1) on early-season waterhemp suppression and soybean growth and yield. Soybean was planted into fall-seeded cereal rye, which was terminated within four days of soybean planting. The experiment was conducted over the 2018, 2019, and 2020 growing seasons in Columbia, Missouri. Effects of cereal rye on early-season waterhemp suppression varied by year and were most consistent at 56 kg ha−1 or higher seeding rates. Linear regression analysis of cereal rye biomass, height, or stand at soybean planting showed inverse relationships with waterhemp emergence. No adverse effects to soybean growth or yield were observed at any of the cereal rye seeding rates relative to plots that lacked cereal rye cover. Result differences among the years suggest that the successfulness of cereal rye on suppression of early-season waterhemp emergence is likely influenced by the amount of waterhemp seed present in the soil seed bank.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Libère Nkurunziza ◽  
Christine A. Watson ◽  
Ingrid Öborn ◽  
Henrik G. Smith ◽  
Göran Bergkvist ◽  
...  

AbstractAgricultural production systems are affected by complex interactions between social and ecological factors, which are often hard to integrate in a common analytical framework. We evaluated differences in crop production among farms by integrating components of several related research disciplines in a single socio-ecological analysis. Specifically, we evaluated spring barley (Hordeum vulgare, L.) performance on 34 farms (organic and conventional) in two agro-ecological zones to unravel the importance of ecological, crop and management factors in the performance of a standard crop. We used Projections to Latent Structures (PLS), a simple but robust analytical tool widely utilized in research disciplines dealing with complex systems (e.g. social sciences and chemometrics), but infrequently in agricultural sciences. We show that barley performance on organic farms was affected by previous management, landscape structure, and soil quality, in contrast to conventional farms where external inputs were the main factors affecting biomass and grain yield. This indicates that more complex management strategies are required in organic than in conventional farming systems. We conclude that the PLS method combining socio-ecological and biophysical factors provides improved understanding of the various interacting factors determining crop performance and can help identify where improvements in the agricultural system are most likely to be effective.


Weed Science ◽  
2016 ◽  
Vol 64 (SP1) ◽  
pp. 570-584 ◽  
Author(s):  
Micheal D. K. Owen

Herbicides have been the principal means of weed control in developed countries for approximately 50 yr because they are the most cost-effective method. Such general use of herbicides has resulted in weed resistance to herbicides, which continues to be a growing problem. Within the past decade, the evolution of resistance to the once-dominant herbicide glyphosate has resulted in major concerns about the future ability to control weeds in many crop systems. Moreover, many weed species have evolved resistance to multiple mechanisms of herbicide action. Given the dearth of new herbicides with novel mechanisms of action, it appears inevitable that weed management programs will need to be supplemented by the use of tactics other than herbicides. However, the inclusion of more diversity for weed management also introduces complexity, cost, and time constraints to current crop production systems. This paper describes broadly the considerations, opportunities, and constraints of diverse weed management tactics to address the burgeoning problems with herbicide resistance.


2017 ◽  
Vol 107 (3) ◽  
pp. 256-263 ◽  
Author(s):  
Mark Mazzola ◽  
Shiri Freilich

Biological disease control of soilborne plant diseases has traditionally employed the biopesticide approach whereby single strains or strain mixtures are introduced into production systems through inundative/inoculative release. The approach has significant barriers that have long been recognized, including a generally limited spectrum of target pathogens for any given biocontrol agent and inadequate colonization of the host rhizosphere, which can plague progress in the utilization of this resource in commercial field-based crop production systems. Thus, although potential exists, this model has continued to lag in its application. New omics’ tools have enabled more rapid screening of microbial populations allowing for the identification of strains with multiple functional attributes that may contribute to pathogen suppression. Similarly, these technologies also enable the characterization of consortia in natural systems which provide the framework for construction of synthetic microbiomes for disease control. Harnessing the potential of the microbiome indigenous to agricultural soils for disease suppression through application of specific management strategies has long been a goal of plant pathologists. Although this tactic also possesses limitation, our enhanced understanding of functional attributes of suppressive soil systems through application of community and metagenomic analysis methods provide opportunity to devise effective resource management schemes. As these microbial communities in large part are fostered by the resources endemic to soil and the rhizosphere, substrate mediated recruitment of disease-suppressive microbiomes constitutes a practical means to foster their establishment in crop production systems.


2021 ◽  
Vol 13 (16) ◽  
pp. 9375
Author(s):  
Erich von Stroheim ◽  
Dana Loyd Keske Hoag

Within a context of beef feedlots and feed-crop production systems, we surveyed farmers to identify their perceived monetary value for the manure they used or could have used. Value is contextual with respect to a number of socio-economic, environmental, regulatory, and physical factors, which influence farmer’s inclinations about how they manage manure. The most desirable manure management strategies are likely practiced by those who perceive its value highest, and, conversely, the least desirable manure management strategies are likely practiced by those who assign the lowest value to it. This study considered factors that affect or relate to farmer perceptions of manure’s value. Using quantile regression, we observed variations in how farmers perceived the value of manure, considering farm and farmer characteristics, farming practices, select preferences, and whether or not they used manure on their own cropland. For example, we found that livestock producers who grow feed for their own cattle value manure differently compared to crop producers who do not manage cattle, most likely due to perceived need. Added years of experience in farming lowered the farmer’s perception of manure’s value. Additionally, extra tillage required when using manure was seen by farmers not as a burden but rather as a benefit.


2018 ◽  
Vol 16 (6) ◽  
pp. 980-990 ◽  
Author(s):  
Luis Fernando Perez-Mercado ◽  
Cecilia Lalander ◽  
Abraham Joel ◽  
Jakob Ottoson ◽  
Mercedes Iriarte ◽  
...  

Abstract In dry areas, the need for irrigation to ensure agricultural production determines the use of all available water sources. However, the water sources used for irrigation are often contaminated by untreated or minimally treated wastewater. Microbial risks from reusing wastewater for vegetable irrigation can be addressed by installing environmental barriers that pathogens must cross to reach humans in the reuse system. Knowledge of pathogen flows inside the system and pathogen removal potential is the first step towards devising a risk management strategy. This study assessed microbe prevalence in farming systems in the Bolivian highlands that use wastewater-polluted sources for irrigation of lettuce. Samples of soil, lettuce and different water sources used in the farming systems were taken during one crop season and concentrations of coliphages, Escherichia coli and helminth eggs were measured. The results showed high spread of these microorganisms throughout the whole system. There was a significant correlation between microbial quality of water and of the harvested produce for several microorganisms. The microbial prevalence in protected shallow wells was found to be significantly lower than in other water sources. These findings can help formulate feasible risk management strategies in contexts where conventional technologies for microbial removal are not possible.


Weed Science ◽  
2012 ◽  
Vol 60 (SP1) ◽  
pp. 31-62 ◽  
Author(s):  
Jason K. Norsworthy ◽  
Sarah M. Ward ◽  
David R. Shaw ◽  
Rick S. Llewellyn ◽  
Robert L. Nichols ◽  
...  

Herbicides are the foundation of weed control in commercial crop-production systems. However, herbicide-resistant (HR) weed populations are evolving rapidly as a natural response to selection pressure imposed by modern agricultural management activities. Mitigating the evolution of herbicide resistance depends on reducing selection through diversification of weed control techniques, minimizing the spread of resistance genes and genotypes via pollen or propagule dispersal, and eliminating additions of weed seed to the soil seedbank. Effective deployment of such a multifaceted approach will require shifting from the current concept of basing weed management on single-year economic thresholds.


2015 ◽  
Vol 66 (12) ◽  
pp. 1230 ◽  
Author(s):  
Ch. Srinivasarao ◽  
Sumanta Kundu ◽  
K. L. Sharma ◽  
Sharanbhoopal Reddy ◽  
A. L. Pharande ◽  
...  

Magnesium (Mg) plays a vital role in photosynthesis, dry matter production and carbon partitioning in sink organs. Hence, four permanent manurial experiments (20–27 years of duration) under the auspices of All India Coordinated Research Project for Dryland Agriculture (AICRPDA) network centres across diverse agro-ecological regions were carried out to examine the soil exchangeable Mg (ex-Mg), crop uptake and overall Mg balance. Groundnut (peanut), finger millet, rice–lentil sequence and post rainy sorghum were the major crops or cropping systems followed in four permanent manure experiments at Anantapuram, Bengaluru, Varanasi and Solapur, respectively. Nutrient management in all experiments involved control (no addition of nutrients), 100% organic, 100% chemical, and integration of organic and chemical. Except in the finger millet-based system, mean ex-Mg status in the entire profile was higher than the sufficiency level (1.0 cmol(+) kg–1 as a critical limit). Status of ex-Mg (cmol(+) kg–1 soil) in soil profiles was in the order: Solapur (3.80) > Varanasi (2.07) > Anantapuram (1.06) > Bengaluru (0.44). A uniform distribution of ex-Mg was observed in plots that received integrated application of organic and chemical fertilisers. In general, improved status of profile ex-Mg (cmol(+) kg–1) over the control was observed in soils under groundnut (0.19–0.78), finger millet (1.90–3.20), and post rainy sorghum (6.50–7.60, except 4.20 in 100% NPK) cropping. Overall, ex-Mg status and balance of different soil types under diverse crop production systems was influenced by several factors, some of which include soil type with varying mineralogy, particle size distribution, nutrient management strategies and rainfall. Significant positive relationships were observed between ex-Mg status and clay content (R2 = 0.94), soil pH (R2 = 0.92), cation exchange capacity (R2 = 0.98) and mean air temperature (R2 = 0.22), whereas a weak relationship was observed with rainfall (R2 = 0.01). The study gives an account of Mg balance in major Indian soil types and recommends further attention on Mg nutrition in current intensive agriculture.


1997 ◽  
Vol 11 (2) ◽  
pp. 384-393 ◽  
Author(s):  
E. James Retzinger ◽  
Carol Mallory-Smith

A classification of herbicides according to their sites of action was developed to help maintain the usefulness of herbicides as a tool in crop production to delay the selection of herbicide-resistant weeds. The classification includes a numbering system for the site of action, the chemical family, and the common name of the herbicide. The United States of America trade name and package mixes also are included.


Weed Science ◽  
2017 ◽  
Vol 65 (6) ◽  
pp. 699-709 ◽  
Author(s):  
Nick T. Harre ◽  
Haozhen Nie ◽  
Renae R. Robertson ◽  
William G. Johnson ◽  
Stephen C. Weller ◽  
...  

Giant ragweed is a highly competitive weed that continually threatens crop production systems due to evolved resistance to acetolactate synthase–inhibiting herbicides (ALS-R) and glyphosate (GR). Two biotypes of GR giant ragweed exist and are differentiated by their response to glyphosate, termed here as rapid response (RR) and non–rapid response (NRR). A comparison of data from surveys of Indiana crop fields done in 2006 and 2014 showed that GR giant ragweed has spread from 15% to 39% of Indiana counties and the NRR biotype is the most prevalent. A TaqMan®single-nucleotide polymorphism genotyping assay was developed to identify ALS-R populations and revealed 47% of GR populations to be ALS-R as well. The magnitude of glyphosate resistance for NRR populations was 4.6 and 5.9 based on GR50and LD50estimates, respectively. For RR populations, these values were 7.8 to 9.2 for GR50estimates and 19.3 to 22.3 for LD50estimates. A novel use of the Imaging-PAM fluorometer was developed to discriminate RR plants by assessing photosystem II quantum yield across the entire leaf surface. H2O2generation in leaves of glyphosate-treated plants was also measured by 3,3′-diaminobenzidine staining and quantified using imagery analysis software. Results show photo-oxidative stress of mature leaves is far greater and occurs more rapidly following glyphosate treatment in RR plants compared with NRR and glyphosate-susceptible plants and is positively associated with glyphosate dose. These results suggest that under continued glyphosate selection pressure, the RR biotype may surpass the NRR biotype as the predominant form of GR giant ragweed in Indiana due to a higher level of glyphosate resistance. Moreover, the differential photo-oxidative stress patterns in response to glyphosate provide evidence of different mechanisms of resistance present in RR and NRR biotypes.


Sign in / Sign up

Export Citation Format

Share Document