Archive for the ‘Weeds’ Category

Researcher aims to alleviate global hunger by deciphering the molecular ‘language’ of plants

by University of Toronto

Credit: CC0 Public Domain

As a young child spending time on her grandparents’ rice farm in the Philippines, Shelley Lumba grew up understanding the benefits of the Green Revolution—the period in the 1950s and 60s when many technological advances were made in agriculture.

“My grandparents told stories about how we didn’t have enough rice to feed our family, much less sell in the market,” she says. “And the Philippines was facing the same crisis—there wasn’t enough rice to feed the country’s population. Of course, it was hitting the poorest people hardest and it was happening in countries around the world.”

Then, Lumba’s grandparents began growing a hybrid strain of rice—one of the newly developed varieties of cereals that were hardier, more nutritious and produced higher yields. Thanks to the hybrid, Lumba’s grandparents were able to feed their family and had rice leftover to sell.

Today, Lumba is an assistant professor in the University of Toronto’s department of cell and systems biology (CSB) in the Faculty of Arts & Science. She hopes her research will lead to advances in agriculture like those made during the Green Revolution and help alleviate hunger, poverty and climate change.

Lumba and her colleagues study how organisms—even those from completely different kingdoms—communicate on a molecular level through a shared “language of life.” For example, plants signal fungi in the soil by giving off hormones called strigolactones (SLs). These “come-hither” hormones trigger the fungi to latch on to the plant, thus establishing a symbiotic relationship in which the fungi provide phosphates to its partner and, in return, receives carbon.

“This symbiosis is ubiquitous,” says Lumba. “If you’re a gardener, you know that new, sterile soil feels like sand, but soil from your planted pots or garden feels heavy with ‘stuff.’ That stuff is all the different fungi and bacteria helping your plants grow.”

SLs and other plant hormones such as gibberrellins trigger germination when conditions are favorable—for example, when there’s sufficient moisture and nutrients in the soil.

Lumba’s goal is to better understand how, at a molecular level, organisms send out these signals and, once received, how those signals are translated into a response. One hope is that the research will lead to new ways of combatting the blight caused by the parasitic Striga hermonthica, commonly known as witchweed.

Witchweed—aka the “violet vampire” for its bright flowers—is considered by the United Nations to be a major impediment to poverty alleviation in Africa. The parasite attacks major cereal crops such as maize, sorghum, millet, sweetcorn and rice, latching on to their roots and draining the host of moisture and nutrients.

Witchweed is particularly difficult to combat because a single plant is capable of producing up to 100,000 seeds. The seeds are so tiny they resemble dust and a square-meter patch of ground can contain thousands. What’s more, the parasite begins to damage crops even before sprouting above ground—in other words, before farmers even know their crops are under attack.

Witchweed can lead to significant crop losses and can sometimes wipe out entire harvests. Damage to agriculture in Africa caused by the plant is estimated at approximately US$9 billion a year, with infestations affecting the lives of over 100 million people in 25 countries.

Like any parasitic organism, witchweed needs a host in order to survive and so it has evolved seeds that can remain dormant in the ground for decades until they “sense” that a potential victim is nearby. At that point, the seeds germinate and latch on to a host.

https://www.youtube.com/embed/PSHXZf0T5Fw?color=whiteCredit: University of Toronto

There have been attempts to fight this blight. Researchers are trying to develop witchweed-resistant strains of cereal crops. There have also been experiments where empty fields are treated with SLs to trigger “suicide germination” in the seeds contained in the soil, but SLs are prohibitively expensive to make.

Progress is slow in part because the problem exists predominantly in underdeveloped countries and because solutions won’t necessarily be lucrative for the companies that could develop them.

Another hurdle is that experimenting with witchweed in a lab is challenging. Because it is a parasite, there are strict regulations, permissions and protocols required to grow it. Also, because it requires a host to survive, there’s the added challenge of parsing what’s going on with the parasite and what’s going on with the host. Finally, researchers can’t manipulate witchweed genes—a tool typical of any such investigation.

But a major breakthrough out of Lumba’s lab has circumvented the challenges associated with witchweed experimentation.

The seeds of Arabidopsis thaliana—a member of the family that includes mustards and cabbages—remain dormant because of proteins that suppress germination in the absence of adequate moisture and warmth. When conditions are suitable, Arabidopsis seeds produce the hormone gibberellins which breaks down repressors of germination.

As described in a recent paper in Nature Plants, Lumba and her collaborators have found a way to introduce SL receptors from witchweed in Arabidopsis, thereby circumventing the gibberellins requirement that normally kickstarts germination. The result is a strain of Arabidopsis which respond to SLs like witchweed, thereby creating an effective model plant for their experiments.

With a growing understanding of how a seed responds to SLs on a molecular level, Lumba’s research has the potential to lead to alternate strategies for combating the parasite. For example, it could lead to the design of molecules that will trigger suicide germination, but that are cheaper and easier to make than SLs.

It also opens up the possibility of other strategies such as the development of molecules that will shut down the germination process entirely—even in the presence of SLs from a host.

“I’m hopeful the ‘bench-to-field’ time won’t be too long,” says Lumba, “and that there will be new strategies coming up soon based on this work.”

In addition to their research related to witchweed, Lumba and her colleagues are also investigating another question with global ramifications: Why and how do fungi respond to SLs? Eighty percent of plants rely on this symbiotic relationship and enhancing the interaction with beneficial fungi could lead to hardier crops and reduce the need for fertilizers, thus reducing phosphate runoff into water systems and lowering the production of greenhouse gasses.

What’s more, it could increase crop yields, the benefits of which Lumba witnessed as a child.

“I knew from my family’s experience how important agriculture is,” she says. “The potential impact of research like this is huge and can improve the lives of so many. It’s about healthy soil for a healthy planet.”

Explore further

Witchweed—destructive by nature

More information: Michael Bunsick et al, SMAX1-dependent seed germination bypasses GA signalling in Arabidopsis and Striga, Nature Plants (2020). DOI: 10.1038/s41477-020-0653-z

Journal information: Nature Plants 

Provided by University of Toronto 

Read Full Post »

Competitive sorghum crops will dent weed invasion

The Land

Bob Freebairn

14 Mar 2022, 5 a.m.


Closer row spacing and heavier sowing rates play a vital part of reducing weeds in grain sorghum crops. Closer row spacing and heavier sowing rates generally have little to no detrimental adverse effect on crop yield.

 Closer row spacing and heavier sowing rates play a vital part of reducing weeds in grain sorghum crops. Closer row spacing and heavier sowing rates generally have little to no detrimental adverse effect on crop yield.


Grain Sorghum Weed Control Guide, written for Pacific Seeds by nationally recognised weed authority Andrew Summervaille, is a comprehensive and outstanding publication dealing with all control aspects. These include herbicides, with lots of insightful comment, fair but often acknowledging limitation of specific products, as well as the important contribution of agronomic aspects to help combat weeds’ effect on yield.

Contributed by Qld Department of Agriculture and Fisheries research agronomist Michael Widderick, is an important section covering weed suppression by growing a competitive sorghum crop. Research over two years has shown that growing a competitive sorghum crop with increased density and reduced row spacing can significantly suppress growth and seed production of weeds like barnyard grass and Feathertop Rhodes grass.

While trial results were not always consistent, crops sown in 0.5 m rows generally suppressed weeds better than in the more traditional 0.75 and 1.0m row spacing. Increasing sorghum plant density from more traditional 5.0 plants sq/m to 10 plants sq/m also generally contributed to a more competitive crop against weeds.

Different varieties (of those tested) had no impact on suppressing weed growth, suggesting cultivar choice will have a lesser impact on sorghum competitiveness than agronomy. However, the researchers note that impact of cultivar may differ across seasons and locations. Also especially noteworthy, was that at least in favourably growing conditions sorghum at narrow row spacing and increased density, did not have any negative impact on sorghum yield.

Weed control in grain sorghum is important for crop yield, as well as for driving down the soil weed seed bank. A combination approach is important for weed control.

 Weed control in grain sorghum is important for crop yield, as well as for driving down the soil weed seed bank. A combination approach is important for weed control.

Therefore, gains in competitiveness and reduction in weed growth can be achieved without reducing yield. Again the researchers note that rarely will a sorghum crop be grown without herbicides, whether they be residual or knockdown, or a combination of both. Integrating a competitive sorghum crop with herbicides should provide an additive effect on reducing in-crop weed pressures, growth and seed production. Over time, this strategy should deplete the weed seed banks, and reduce their impact on sorghum production.

Also read: Perfect growing season sees great sorghum crops in north-west

A further valuable part of the publication is discussion of the role of Imidazolinone technology in sorghum, developed by Advanta Seeds. Sorghum has well and truly joined the list of crops with varieties that provide tolerance to Imidazolinone (IMI herbicides). Note this is not GMO technology. This technology allows the application of a new range of registered herbicides at recommended rates without causing crop damage.

Intervix (imazamox + imazapyr) is an example of an IMI herbicide. IMI products have broad spectrum activity with variation in the activity of individual herbicides for pre-emergence and post-emergence control. Control of broadleaf weeds post-emergence is normally limited to small weeds and relies to a measure on the effectiveness of crop competition occurring subsequent to application particularly for less susceptible species. While IMI herbicides like Intervix control a wide range of broadleaf and grass weeds it does, like most herbicides, have its limitations like not controlling fleabane or Feathertop Rhodes grass.

Grain Sorghum Weed Control Guide, written for Pacific Seeds by nationally recognised weed authority Andrew Summervaille, is a valuable reference.

 Grain Sorghum Weed Control Guide, written for Pacific Seeds by nationally recognised weed authority Andrew Summervaille, is a valuable reference.

Excellent tables are presented in the publication that covers aspects like effect of various herbicides on specific weeds. These are detailed in tables for pre-emergent and post emergent. Tables also detail aspects like plant back intervals, application timing, rates per ha, rainfall requirement and the like.

Especially valuable is Andrew Summervaille’s discussions about various herbicide products. He highlights advantages and disadvantages of the various herbicides. Planning for control of difficult weeds, like fleabane, Feathertop Rhodes grass, and even well known weeds like barnyard grass and liver-seed grass that have or are developing resistance to some herbicides, requires carful choice of herbicide and their application.

Further details obtain the booklet via http://www.pacificseeds.com.au/wp-content/uploads/2021/07/Pacific-Seeds-Grain-sorghum-weed-control-guide-_Low-Res.pdf

Next week: Ensuring legumes are a vital part of the pasture mix.

  • Bob Freebairn is an agricultural consultant based at Coonabarabran. Email robert.freebairn@bigpond.com or contact (0428) 752 149.

Read Full Post »


Commence annihilation of invasive alien plant species immediately, HC tells govt.

Mohamed Imranullah S.


UPDATED: FEBRUARY 28, 2022 20:27 IST

In 2015, the court had ordered the annihilation of exotic species and the restoration of shola forests in the hilly regions of the State.

In 2015, the court had ordered the annihilation of exotic species and the restoration of shola forests in the hilly regions of the State.

It wants pilot project to begin immediately as it has already been 7 years since it passed orders in 2015 

The Madras High Court on Monday asked the State government to immediately commence a pilot project for the eradication of invasive alien plant species such as eucalyptus, wattle and prosopis juliflora, and carry out proper ecological restoration of natural habitats.

A Division Bench of Justices V. Bharathidasan and N. Sathish Kumar commended Environment and Forests Secretary Supriya Sahu for having come up with a draft Tamil Nadu Policy on Invasive Plants and Ecological Restoration (TNPIPER) and making it available in the public domain.

However, not wanting things to remain on paper any longer as it has already been seven years since the court, in 2015, ordered the annihilation of exotic species and the restoration of shola forests in the hilly regions of the State, the judges asked the Secretary to start the work immediately.

They asked her to come back to the court on March 18 and report that the work had begun. She agreed, and assured the court that the work will begin as early as possible. Earlier, she informed the judges that the draft policy was put in the public domain to invite comments.

The opinions of various stakeholders were obtained and, in the second stage, seven teams of forest officials were constituted to visit Kerala, Karnataka, Telangana, Madhya Pradesh, Odisha, Gujarat and Rajasthan to study the practices followed in those States. The teams had already gone there.

The teams were expected to submit their reports to the State government by March 9. Further, Chief Secretary V. Irai Anbu had approved a proposal worth ₹10 crore, and the funds would be released after clearance was obtained from the Union Ministry of Environment and Forests, the Secretary said.

However, ₹6 crore from the National Bank for Agriculture and Rural Development (NABARD) was already available for the eradication of invasive species and restoration of natural habitat, she said. After taking note of her submissions, the judges said the money could be used for the pilot project.

Ms. Sahu also assured the court that the Tamil Nadu Wildlife Crime Control Bureau will start functioning soon, after obtaining the guidance of an expert committee. She said it was a first-of-its-kind initiative taken by the government because of its commitment to the cause.

The judges further asked the Secretary to consider authorising the police as well as customs officials to prosecute offenders under the Wildlife (Protection) Act of 1972, since the law, as it stands today, permits trial courts to take cognisance of prosecution launched by forest officials alone.

Our code of editorial values

Read Full Post »

Study ranks potentially harmful invasive alien plant species in Ghana


Study ranks potentially harmful invasive alien plant species in Ghana
A farmer shows cassava root affected by cassava brown streak virus alongside a healthy root in a country where the disease is present – one of the 64 pathogens assessed by the scientists. Credit: CABI

A CABI-led study has conducted a comprehensive survey of nearly 200 potentially harmful alien plant species that could have a detrimental impact upon agriculture, forestry and biodiversity in Ghana once they enter the country.

Invasive Alien Species (IAS) continue to shape the global landscape through their effects on biological diversity and agricultural productivity. The effects are particularly pronounced in Sub-Saharan Africa, which has seen the arrival of many IAS in recent years. This has been attributed to porous borders, weak cross border biosecurity, and inadequate capacity to limit or stop invasions.

The research, the findings of which are published in the journal NeoBiota, ranks 110 arthropod and 64 pathogenic species that pose the greatest threat but are not yet officially present in the country. However, they could arrive as ‘stowaways’ in cargo from other countries around the world, the scientists believe.

Dr. Marc Kenis, Head Risk Analysis and Invasion Ecology at CABI, led on the horizon scanning exercise supported by colleagues from a range of institutions including Ghana’s Plant Protection and Regulatory Services Directorate (PPRSD).

Among the top arthropods prioritized by Dr. Kenis and his team were the pink hibiscus mealybug (Maconellicoccus hirsutus Green) and melon thrips (Thrips palmi Karny) while the top pathogens highlighted include cassava brown streak virus and Maize lethal necrosis disease.

Cassava in Ghana, for example, is a main staple crop and contributes about 22 percent and 30 percent to the Agricultural Gross Domestic Product (AGDP) and daily calories intake respectively. The crop however, can be at risk from cassava brown streak virus which can reduce yields by up to 70 percent.

Maize lethal necrosis disease, on the other hand for instance, can be a major disruptor of maize crops in Ghana where maize accounts for more than 50 percent of the country’s total cereal production. The disease can cause losses of between 50–90 percent depending on the variety of maize and the growing conditions of the year.

The scientists also found other species recorded in Africa that included 19 arthropod and 46 pathogenic species which were already recorded in the neighboring countries of Burkina Faso, Côte d’Ivoire, and Togo.

Dr. Kenis, who is based at CABI’s center in Switzerland, said, “The ultimate objective of this research was to enable prioritization of actions including pest risk analysis, prevention, surveillance and contingency plans. Prioritization was carried out using an adapted version of horizon scanning and consensus methods developed for ranking IAS worldwide.

“We have demonstrated that through horizon scanning, a country can identify potential invasive plant pests, both invertebrates and pathogens, and use the information to determine the risk associated with each.

“This will enable the country to invest the limited resources in priority actions such as preventing arrival and establishment of IAS, Pest Risk Analysis (PRA), surveillance and developing contingency plans.

“This study can serve as a model for future projects on plant pests’ prioritization in Africa and elsewhere. It would be applicable for assessing the risk of invasive plant pests in any country or region, e.g. trade blocks, with minor modifications of the method, particularly in the mini-PRA protocol used to score species.”

The full lists of arthropod and pathogenic species surveyed can be found within the full paper which can be read online.

Mr Prudence Attipoe, Deputy Director Head Plant Quarantine Division, PPRSD, said, “The horizon scanning exercise for Ghana would give the PPRSD an insight into invasive pests which could possibly enter the Nation. The tool is timely and appropriate for conducting PRA for planning, training and future preparedness. The success of this exercise would pre-empt the introduction of these invasive pests into the country in order to protect Ghana’s agriculture, forestry and also cause staff of PPRSD to be more vigilant at the borders for these pests.”

Explore further

Opportunities for natural enemy to fight devastating fall armyworm

More information: Marc Kenis et al, Horizon scanning for prioritising invasive alien species with potential to threaten agriculture and biodiversity in Ghana, NeoBiota (2022). DOI: 10.3897/neobiota.71.72577

Journal information: NeoBiota 

Provided by CABI

Newsletter sign up

Read Full Post »

Bud’, from Carbon Robotics

Robot lasers weeds from the fields without herbicide

Seattle autonomous robotics company Carbon Robotics aims to confront the multi-billion dollar global herbicide market with its laser-armed weed elimination robot. The machine, named “Bud”, rolls through farm fields using artificial intelligence to discern weeds from crops and using a high-power laser to kill the weeds. This will enable farmers to cultivate crops with less herbicide and reduced labor, improving crop yields and saving money.


Bud’s robot brain is an Nvidia AI processor that gathers information from a dozen high-resolution cameras to feed its crop and weed computer vision models. Bud carries lighting so that it can illuminate the scene to let the cameras spot weeds at night.

Source: designnews.com

Read Full Post »

Laser-Armed Robot Terminates Weeds Without Herbicide

Design News

Carbon RoboticsCarbon Robotics machine.jpgCarbon Robotics autonomous weeder, “Bud.”Carbon Robotics robots fry weeds with lasers instead of chemicals.

Dan Carney | Dec 13, 2021

The global herbicide market was $33.65 billion in 2020, according to ResearchandMarkets.com, but Carbon Robotics, an autonomous robotics company, aims to put a dent in that with an autonomous laser-armed weed elimination robot.

Like “The Terminator” for weeds, the Carbon Robotics machine, dubbed “Bud,” rolls through farm fields using artificial intelligence to discern weeds from crops and using a high-power laser to kill the weeds. This lets farmers cultivate crops with less herbicide and reduced labor, improving crop yields and saving money.https://www.youtube.com/embed/AP0yiOI8Qas

Related: How to Build a Better Planting Operation

“AI and deep learning technology are creating efficiencies across a variety of industries and we’re excited to apply it to agriculture,” said Carbon Robotics CEO and Founder, Paul Mikesell. “Farmers, and others in the global food supply chain, are innovating now more than ever to keep the world fed. Our goal at Carbon Robotics is to create tools that address their most challenging problems, including weed management and elimination.”

Carbon Robotics cites these benefits for farmers deploying its robots:  

  • A significant increase in crop yield and quality: Lasers leave the soil microbiology undisturbed, unlike tillage. The lack of herbicides and soil disruption paves the way for a regenerative approach, which leads to healthy crops and higher yields.
  • A reduction in overall costs: Automated robots enable farmers to reduce the highly variable cost of manual labor as well as reduce the use of crop inputs such as herbicides and fertilizers. Labor is often farmers’ biggest cost and crop inputs account for 28.2 percent of their total expenses. Reducing costs in both these areas is a huge benefit.
  • Adoption of regenerative farming practices: Traditional chemicals used by farmers, such as herbicides, deteriorate soil health and are tied to health problems in humans and other mammals. A laser-powered, autonomous weed management solution reduces or eliminates farmers’ needs for herbicides.
  • An economical path to organic farming: One of the largest obstacles to organic farming is cost-effective weed control. A solution to weed management that doesn’t require herbicides or an increase in manual labor provides farmers with a more realistic path to classifying their crops as organic.

Related: Autonomous-Capable Electric Tractor Promises Improved Farm Productivity

The Bud robot’s brain is an Nvidia AI processor that gathers information from a dozen high-resolution cameras to feed its crop and weed computer vision models. Bud carries lighting so that it can illuminate the scene to let the cameras spot weeds at night.

The business end of the robot contains eight independent weed-killing units, each employing a 150-watt laser that can fire every 50 milliseconds and hit targets with 3 mm accuracy. These have the capacity to zap more than 100,000 weeds per hour. It also has lidar sensors for obstacle detection. The entire 9,500-lb. machine is powered by a 74-horsepower Cummins QSF2.8 diesel engine powering four hydraulic drive motors.

It sounds straightforward, but it took a lot of work to make this practical. “Some of the problems we encountered are having to generate a lot of power in a mobile platform and then distribute that to all of our lasers and cooling systems,” observed Carbon Robotics’ electrical engineer Ben Neubauer. “One of the things that is really enjoyable about working on agriculture robotics like this is working with a lot of different industries and systems,” he added.https://www.youtube.com/embed/FgO4rl5H3Cg

Of course, the important thing with a weed terminator is avoiding collateral damage of crops. “One of the first things we worked on at Carbon is the ability to drive down the field without going into bed tops, without crossing them and going over crops,” said Raven Pillmann, deep learning software engineer. “The way we want to do that is by avoiding any GPS, location waypoints, or any sort of plotting. Our approach was to use deep learning and create a furrow detection model. It takes in images with the camera which has RGB and depth sensors, it will run this through a model that gives out the location of the furrow. At the same time running concurrently in another process, we have our controls which will take in the latest prediction, and it will look at where the robot is aligned and the difference between that and the furrow prediction and that will tell it which way to turn the wheel.”

These robots can handle row crops in fields between 200 acres and tens of thousands of acres in size, with each robot clearing 15-20 acres per day to replace several deployments of hand-weeding crews. The robots have undergone testing on specialty crops farms, working on fields with a variety of crops, including broccoli and onions.

“This is one of the most innovative and valuable technologies that I’ve seen as a farmer,” said James Johnson of Carzalia Valley Produce in New Mexico, who uses Carbon Robotics technology on his farm. “I expect the robots to go mainstream because of how effectively they address some of farming’s most critical issues, including the overuse of chemicals, process efficiency, and labor. These robots work with a variety of crops, are autonomous and organic. The sky’s the limit.”

Carzalia Valley Produce liked the idea of switching to organic farming practices, Johnson added, but couldn’t find a way to make it work until using the autonomous weeding robot. “Two years ago I thought that eventually, I could go organic,” he said. “After a year of trying my first regenerative [practices], I was back to thinking ‘There’s no way I can go organic.’ The biggest hurdle I had with transitioning to organic was organic weed control. This solves that problem. Conventional weeding consists of mechanical cultivation, herbicide application, as well as hand weeding. Any kind of chemical input, be it chemical fertilizer, herbicide, insecticide, or anything else that we would apply has an adverse effect either on plant health or soil health.”

So, as long as we can keep Bud and its brethren tending the crops with its lasers and not chasing saviors of mankind through the streets of 1984 Los Angeles, then only the weeds have anything to fear from these terminators!

Read Full Post »

No need for herbicides to remove weeds
1 December 2021

© Federal Office of Agriculture and Food/Fraunhofer

Fraunhofer researchers have collaborated with partners to develop a platform to remove weeds fully automatically. The mobile AMU-Bot robot system navigates using optical sensors and removes weeds mechanically without the need for chemicals. The researchers have also been working on a comprehensive, data-supported ecosystem for the resource-efficient and environmentally friendly automation of agricultural processes, writes Fraunhofer in a press release.

Weeds in tree nurseries, vegetable gardens and orchards are a grower’s worst nightmare. Especially in the early stages of the crop’s growth, weeds compete with crops for water, light and nutrients. Removing them by manual hoeing is labor-intensive and using herbicides is far from ideal as they pollute the environment. The Fraunhofer Institute for Manufacturing Engineering and Automation IPA in Stuttgart has joined forces with partners to develop a mobile, mechanical system that reliably removes weeds in a cost-effective and environmentally friendly manner. The autonomous caterpillar vehicle, AMU-Bot (“AMU” being short for “autonomous mechanical weed control” in German), drives between the rows of saplings in the tree nursery and removes any weeds using rotary harrows. The rotating blades are attached to a height-adjustable manipulator. At the end of the row of trees, the caterpillar vehicle turns around and autonomously starts on the next row.

Navigation with LiDAR scanners
The project team, headed by Kevin Bregler (Head of Field Robotics at the Robot and Assistive Systems department), together with partners Bosch and KommTek used optical sensors for the navigation system. The LiDAR (light detection and ranging) scanners installed in the robot system continuously emit laser pulses as the vehicle moves, which are then reflected by objects in the surrounding area. The distances to these objects can be calculated based on the time it takes for the reflected laser pulses to reach the sensor again. This produces a 3D point cloud of the environment. The robot system uses this to find its way and determine the position of plants or trees.

Kevin Bregler explains: “AMU-Bot is not yet able to classify all plants; however, it can recognize crops such as trees and shrubs in the rows of the tree nursery cultivations. Moreover, the distances between the individual crops are calculated. Using this information, the weeds can then be reliably removed. The robot uses these data to navigate along the rows while the manipulator removes any weeds.”

Even weeds in the spaces between the plants or trees can be reliably killed off. To that end, the manipulator moves into the gaps between the crops. The weeds do not need to be collected and are left on the ground to dry out. Thanks to its caterpillar drive, the self-driving weed killer moves along the ground with ease and is extremely stable. Even holes in the ground created when saplings are removed do not pose a problem for AMU-Bot. The AMU-Bot platform is economical, robust, easy to operate and highly efficient. Rotary harrows, for example, have long since proven successful in agriculture. They are often used to break up the soil prior to sowing crops. Fraunhofer expert Bregler says: “Removing weeds is a very relevant topic and one that is rather complex. There are various approaches that can be taken: grubbing, cutting, hoeing, flaming or treating the weeds with herbicides. However, herbicides are no longer popular, especially in ecological agriculture and for tree nurseries or orchards. Our method completely avoids the use of chemicals.”

Robust, reliable and cost-effective
The project managers made a conscious decision to develop a seemingly simple solution. “A system that classifies the different individual plants requires high-resolution cameras, AI-supported image recognition algorithms and plant profiles stored in a database. These systems are far more complex and expensive. Not only that, but they cannot readily switch to working in new contexts,” explains Bregler. In comparison, the AMU-Bot platform relies on the sophisticated interplay of three fully developed modules: caterpillar vehicle, navigator system and manipulator. AMU-Bot is also the result of an efficient partnership. Bosch is responsible for the navigation and sensor system, while KommTek developed the caterpillar drive. Fraunhofer IPA engineered the height-adjustable manipulator, including rotary harrows, and was responsible for overall coordination. The project was supported by the German Federal Ministry of Food and Agriculture (BMEL) and the German Federal Office of Agriculture and Food (BLE) was the project sponsor. The Fraunhofer experts are already planning the next step. Together with seven other Fraunhofer Institutes, IPA expert Kevin Bregler and the project team are working on a new, high-performance ecosystem called COGNAC (Cognitive Agriculture). Digital services and data, which also include interactions between biospheres and production, are networked to form this ecosystem. In addition, COGNAC integrates intelligent sensors and robotics. The aim is to create flexible and intelligent automation of sustainable agriculture — including weed control.

Read Full Post »

How to create an integrated weed management strategy for grassweeds in cereals

Provided by

Farmer’s Weekly

At Bayer Crop Science, we’re committed to supporting farmers on their journey, putting health, nutrition and sustainable food production at the very heart of what we do. As the UK’s leading agricultural innovators across seeds, crop protection products and services, we want to help shape the future of farming in a way that benefits everyone.© Bayer Crop Science© Bayer Crop Science

Grassweeds, such as blackgrass but also increasingly ryegrass and bromes, are probably the main agronomic threat to cereal production in the UK.

Without a good control strategy, over time they can increase to levels that threaten the economic viability of crop production.

For many, the main control strategy has been the use of herbicides. The most recent pesticide usage survey in 2016 suggested over 98% of wheat crops received a herbicide. That’s unlikely to have changed much in the intervening years.

But reliance just on herbicides to control weeds is fraught with danger. History has shown that grassweeds are incredibly adaptable and with active ingredients both becoming more difficult to register for use and being removed from the market, the remaining ones are even more at risk from grassweeds developing resistant to them.

That increasing difficulty to control grassweeds with chemicals has been the primary driver for growers to consider and use non-chemical methods of control.

In a lot of cases incorporating those alternatives has coincided with improved grassweed control – and is now commonly cited as the key to controlling blackgrass especially.

But it just highlights that integrated weed management is usually the key to long-term sustainable weed control programmes.

What is integrated weed management?

At its simplest integrated weed management is about using multiple methods of controlling weeds, including cultural, genetic, mechanical, biological and chemical controls, rather than just relying on one method alone.

In reality, for most that means reducing the reliance on herbicides by integrating a wide range of cultural control options including cultivations, drilling date, cropping choice, mechanical weed control and other physical controls.

What do you need to know to put an integrated weed management plan together?

Understanding a weed’s biology and life cycle – a weed’s seasonal pattern of growth and reproduction – is perhaps the most important starting point for an integrated weed management plant, after knowing what weeds you’re trying to control.

Within the life cycle there are generally five potential ways to control weeds:

1. By preventing seed return

This is crucial for grassweeds, which produce high levels of seed and can establish large viable seedbanks in one season.

Example control measures that can help prevent seed return include the use of glyphosate to aggressively target blackgrass patches in early June and harvest weed seed management such as cage mills retrofitted on combines to pulverise ryegrass seed.

2. By depleting the seedbank

The seedbank is the seeds in the soil resulting from seeding in previous years. Seed numbers can decrease in time as they germinate, decay or are eaten by wildlife, but some buried seed can survive for many years.

Understanding this dynamic is crucial – it’s both possible to deplete the seed bank by good management and make it worse.

For example, ploughing can be a good tactic to reduce grassweeds as it will bury seeds to a depth from where they are unable to germinate, but can also be a poor tactic if done too often and weed seeds that had been buried are brought back to the surface and are able to germinate.

Other examples of control tactics that will help deplete seedbanks include stale seedbeds and delayed drilling, which encourage weed seeds to germinate and then be destroyed either mechanically or with glyphosate before the crop is drilled.

3. By killing weed seedlings

Knowing when weed seeds will emerge can help determine the most effective control methods. For example, blackgrass typically germinates in the autumn and means that delaying planting a crop until the spring can help reduce the amount of germination in the crop.

As weeds grow, they will compete with the crop, but the damage this causes depends on the species, the density of weed, the competitive ability of the crop and the growth stage when the crop and weeds compete.

Some weeds might be highly competitive, while others pose little threat and can be left uncontrolled and may be valuable for wildlife. Most grassweeds fall into the highly competitive segment.

4. By stopping seed set

While by this stage weeds may have competed with the crop, as with preventing seed return, preventing seed set reduces weed seed production and in turn reduces the seedbank for future years.

This matters most with weeds that are difficult to control, such as grassweeds resistant to herbicides, and is easiest when weed populations are low. Hand rogueing, for example, can be a crucial tactic to prevent early-stage infestations from becoming a larger problem.

5. By applying good on-farm hygiene

Stopping weed seeds arriving on farm through good hygiene, for example on machinery, in seed, straw, compost or sewage sludge is a key step in managing weed spread.

There’s plenty of evidence that machinery has been a key factor in the spread of blackgrass, so for example insisting contractors blow down combines or balers before coming onto your farm is good practice.

The same applies to when moving machinery from a heavily infested field to prevent a weed problem spreading from field to field.

So why does this matter? Part one of building any good integrated weed management plan is considering your target weeds life cycle and how you can use as many of those opportunities to disrupt its ability to be successful and spread. If you can target weeds at more than one stage during the season, there’s a greater chance of a sustainable strategy.

What types of tactics are available to control weeds?

While herbicides are by far the most common form of weed control, and particularly for grassweeds, used proactively rather than reactively – e.g. pre-emergence rather than post-emergence, there are a surprisingly large number of alternative tactics that can be used.

But unlike herbicides where if a weed is sensitive, and for grassweeds that is obviously a big ‘if’, control can be close to 100%, most other weed control approaches need to be integrated with a good knowledge of weed biology to be successful.

The 2019 AHDB ‘Research Review: Weed control options and future opportunities for UK crops’ (PDF) breaks down weed control tactics into seven distinct types: cultural, non-chemical, chemical, novel and emerging technologies, digital tools, genetic tools and preventative weed control.

In total the report describes over 50 different potential tactics that could be used, ranging from the common such as existing chemistry, rotation, drilling date and cultivations to emerging ideas, such as remote sensing and CRISPR technology.

Building a good integrated weed management plan will use as many of these as required to diversify weed management and reduce reliance on herbicides. Where possible IWM will also promote the use of site-specific weed management and target applications to reduce herbicide impacts.

This article is part of the following collection(s):

Some collections offer CPD points from accrediting bodies, visit ourLearning Centreto find out more.

Read Full Post »

Possible tool in the war on resistant weeds

Wallaces Farmer

Prashant JhaRedekop Seed Control Unit harvesting soybeans

NO RESISTANCE TO STEEL: Iowa State University is among the leading places in the U.S. to put the Redekop Seed Control Unit to the test — including on a field in Story County, Iowa, and in Harrison County, Iowa, on a field owned by Iowa Pest Resistance Management Program participant Larry Buss.For the second year, ISU is testing a Redekop Seed Control Unit on Iowa farm fields to determine the economic feasibility of harvest weed-seed control.

Tyler Harris | Oct 25, 2021

Larry Buss often says, “I haven’t seen any weeds yet that are resistant to steel.” Steel can refer to preplant tillage, cultivation — or in more recent cases, mechanical control of harvested weed seed.

Ever since Palmer amaranth was identified in Harrison County, Iowa, in 2013, Buss has been vigilant in doing his part to slow the spread of herbicide resistant weeds in Iowa and across the continent — spreading the word with national organizations like the Weed Science Society of America and Entomological Society of America, and at international events like the Manitoba Agronomists Conference and the Soil and Water Conservation Society’s Annual Conference.

A Redekop unit being tested on 500 acres of soybeans in Story County last year to kill waterhemp seed at harvest
REDUCED WEED SEED BANK: A Redekop unit was tested on 500 acres of soybeans in Story County last year to kill waterhemp seed at harvest. “We had about 90% or more kill efficacy for waterhemp — and that was a multiple herbicide-resistant waterhemp population in soybean,” says Prashant Jha, ISU associate professor and Extension weed specialist. (Photo by Prashant Jha)

These efforts grew with the launch of the Iowa Pest Resistance Management Program in 2017. Since then, Buss has collaborated with Iowa State University researchers, agronomists, landowners, crop consultants, ag lenders and commodity organizations to monitor the spread of resistance on farms in Harrison County, and test different practices and herbicide programs to control weeds like Palmer amaranth, waterhemp, marestail and giant ragweed.

Most recently, this involves harvest weed-seed techniques — more specifically, using a Redekop Seed Control Unit. Designed to be used with a John Deere combine, the Redekop unit uses high-impact mills to break the seed through physical destruction as it comes out of the back of the combine, killing the seed and preventing germination. According to Saskatoon, Saskatchewan-based Redekop, the unit can destroy as much as 98% or more of weed-seed germination during harvest. The unit also allows the operator to turn it on and off on the go.

“I have a few weeds at a field by Dunlap, so we’re going to test it up there,” Buss says. “Then, we are going to get a sample of the weed seed behind the combine to see if the unit helps with germination destruction.”ADVERTISING

Off to a good start

Iowa is one of the first states the unit has been tested in the U.S. — it was tested by Prashant Jha, an ISU associate professor and Extension weed specialist in 2020 at a farm in Story County.

Jha notes one Redekop unit was tested on 500 acres of soybeans in Story County last year, with promising results for controlling waterhemp seed at harvest. However, he notes the study is ongoing.

“We had about 90% or more kill efficacy for waterhemp — and that was a multiple-herbicide-resistant waterhemp population in soybean,” Jha says. “We don’t know what level of resistance those waterhemp plants had, but they had survived multiple applications, and that’s why it made perfect sense to do some harvest weed-seed control. The same is true in Harrison County — they have populations resistant to Group 9 as well as Group 2 [herbicides] and most likely PPO and HPPD inhibitors.”

This year, after running the seed destructor in soybean fields, Jha will monitor the changes in weed seed bank density over time by collecting soil core samples in the fall, and then counting weed emergence in the following spring.

“We will estimate how much of the initial weed-seed bank has emerged and how much has survived herbicide applications, and how many weeds are present at harvest and the weed-seed-kill efficacy of the Redekop seed unit,” Jha says.

Economic feasibility

Of course, one of the big questions to be answered is: At what point does it become economically feasible to use harvest weed-seed control? Jha notes while the Redekop unit costs about $70,000, it will take time to determine how long it takes to pay for the machine by reducing the weed-seed bank.

PROBLEM WEEDS: Since 2017, growers, agronomists, Extension educators and other stakeholders in Harrison County have studied herbicide resistance in weeds as part of the Iowa Pest Resistance Management Program. This includes some key problem weeds in the area: Palmer amaranth (pictured), waterhemp, giant ragweed and marestail. (Photo by Bob Hartzler)

“It won’t happen in one year, but we expect at least a 90% reduction in the seed bank,” he says. “There will be some header/thresher loss — probably close to 25% to 30%. Kevin Bradley at the University of Missouri has seen close to 25% header loss, and some of the weed seeds are getting shattered. We had close to 30% to 33% header loss last year. It’s not stand-alone, but we expect that, of the remaining 67% to 70% seed going inside the unit, 95% will be killed.”

And there are other factors — like the potential savings on herbicide application costs in the future.

“There are millions of dollars right now going into managing herbicide resistance in corn and soybeans,” Jha adds.

“If you calculate the cost of three applications in a season — burndown, pre- and postresidual — can we cut that cost by reducing the weed-seed bank in a three- to four- year time frame, and increase the longevity of the herbicide? More importantly, we are quickly running out of herbicide options because of multiple-herbicide-resistant waterhemp and Palmer amaranth populations,” Jha says.

Last-resort option

Larry Buss notes that for the time being, the best method for weed control is to keep them from competing with crops during the growing season, by controlling them upfront and preventing them from going to seed and expanding the weed-seed bank.

Larry Buss speaks at a field day
SPREADING THE WORD: Larry Buss speaks at a field day as part of a Weed Science Society of America and Entomological Society of America event in this 2019 photo. Buss notes that growers in Harrison County and across Iowa are getting the message that weeds must be controlled early on with a full rate and multiples modes of action. (Photo by Ethan Stoetzer)

“I’m not going to spend money on it yet, because I would prefer to invest it in a better sprayer or a more robust herbicide program. If herbicide resistance continues to get worse, we can use harvest weed-seed methods to significantly reduce the weed-seed bank, because it’s going to wipe out the weed mechanically,” he adds. “Weeds won’t be resistant to steel, so you can kill it with preplant tillage, cultivation — or you kill the seed with the Redekop Seed Control Unit. But before we do that, I think farmers will look to control weeds upfront so they don’t compete with the crop.”

And, Buss notes the outreach efforts of the Pest Resistance Management Program are paying off — while herbicide resistance continues to be a challenge, people are aware it’s a problem and are taking steps to slow its spread.

“I’m going to pat ourselves, in Harrison County and the Iowa Pest Resistance Management Program, on the back,” he says. “Because I think we’re getting the message out that we’ve got to control weeds early on with a full rate of herbicide, and multiples modes of action.”

Read Full Post »

Lentil breeding advances set to continue

North Queensland Register

Gregor Heard

Gregor Heard@grheard20 Oct 2021, 3 p.m.Grains

Agriculture Victoria lentil breeder Arun Shunmugam with a promising line of yet to be commercially released lentils in a trial at the pulse trial site at Propodollah, near Nhill, last week.

 Agriculture Victoria lentil breeder Arun Shunmugam with a promising line of yet to be commercially released lentils in a trial at the pulse trial site at Propodollah, near Nhill, last week.Aa

IN A YEAR with many contenders for most lucrative crop lentils are making a solid charge.

Values are in excess of $1000 a tonne, primarily in light of a lack of product from the world’s largest exporter of the legume, Canada, and an easing of tariffs from the world’s largest importer, India.https://7d116f708d3262b63c59ece0b6732cc5.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.html

RELATED: New field peas

It has farmers in the lentil belt through Victoria and South Australia excited about this year’s harvest, with a kind season in regions such as the Wimmera meaning many crops are displaying outstanding yield potential.

Given the buzz around the crop at present it is no wonder lentils were one of the major talking points at last week’s Southern Pulse Field Day near Nhill in Victoria’s Wimmera.

Agriculture Victoria pulse breeders Jason Brand and Arun Shunmugam said there were a number of promising new developments in the lentil breeding pipeline.

In particular two cultivars yet to be commercialised are performing well in trials, with Dr Brand saying there was huge yield potential in the two lines.

Dr Shunmugam said other focuses of breeders included looking to incorporate more frost resistant genetic material along with further advances in herbicide resistant and tolerant varieties.

The crowd at the Nhill field day said Clearfield / imi-tolerant lines such as Hallmark and Hurricane were popular as they gave flexibility within the rotation and reduced the plant-back risk when planted following another Clearfield line.

Dr Brand said frost and waterlogging tolerance remained two key objectives.

He said there was a complex interaction which meant plants just metres apart could fare vastly differently.

“You can see even in the trials here that some plants look like they’ve incurred frost damage and just a couple of metres away with slightly different soil type and slightly higher up they are unaffected.

“Some form of tolerance to both these stresses would be a great win for the industry,” Dr Brand said.

He said the breeding sector wanted feedback from growers about what herbicide tolerance traits were wanted.

“It is a complex one as we have to manage market expectations and maximum residue limits in with what is going to work well agronomically, but we’re really keen to hear what growers would be interested in seeing in future varieties,” he said.

Read Full Post »

India gets first herbicide-tolerant & non-GM rice varieties; launch today

Indian Express, Oct. 19, 2021

The varieties — Pusa Basmati 1979 and Pusa Basmati 1985 — contain a mutated acetolactate synthase (ALS) gene making it possible for farmers to spray Imazethapyr, a broad-spectrum herbicide, to control weeds.

  • I

Written by Harish Damodaran | New Delhi |
Updated: September 28, 2021 7:37:06 am

IARI director AK Singh at a trial field containing both herbicide-tolerant basmati and normal basmati (left plot), whose plants have been killed along with weeds after spraying Imazethapyr. (Photo by Harish Damodaran)

The Indian Agricultural Research Institute (IARI) has developed the country’s first-ever non-GM (genetically modified) herbicide-tolerant rice varieties that can be directly seeded and significantly save water and labour compared to conventional transplanting.

The varieties — Pusa Basmati 1979 and Pusa Basmati 1985 — contain a mutated acetolactate synthase (ALS) gene making it possible for farmers to spray Imazethapyr, a broad-spectrum herbicide, to control weeds. This dispenses with the need to prepare nurseries where paddy seeds are first raised into young plants, before being uprooted and replanted 25-35 days later in the main field.

The two new varieties are scheduled to be officially released by Prime Minister Narendra Modi on Tuesday.https://56428c50993d1e8aab4b4fb64a9125c7.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.htmlRead |Need to think of ‘respectable jobs’ for landless and small farm households: NITI Aayog member

Paddy transplantation is both labour- and water-intensive. The field where the seedlings are transplanted has to be “puddled” or tilled in standing water. For the first three weeks or so after transplanting, the plants are irrigated almost daily to maintain a water depth of 4-5 cm. Farmers continue giving water every two-three days even for the next four-five weeks when the crop is in tillering (stem development) stage.

“Water is a natural herbicide that takes care of weeds in the paddy crop’s early-growth period. The new varieties simply replace water with Imazethapyr and there’s no need for nursery, puddling, transplanting and flooding of fields. You can sow paddy directly, just like wheat,” said A K Singh, director of IARI.Top News Right Now


Imazethapyr, effective against a range of broadleaf, grassy and sedge weeds, can’t be used on normal paddy, as the chemical does not distinguish between the crop and the invasive plants. The ALS gene in rice codes for an enzyme (protein) that synthesises amino acids for crop growth and development. The herbicide sprayed on normal rice plants binds itself to the ALS enzymes, inhibiting their production of amino acids.

The new basmati varieties contain an ALS gene whose DNA sequence has been altered using ethyl methanesulfonate, a chemical mutant. As a result, the ALS enzymes no longer have binding sites for Imazethapyr and amino acid synthesis isn’t inhibited. The plants can also now “tolerate” application of the herbicide, and hence it kills only the weeds.Also Read |India must shed obsession with ‘marginal farmers’. Their future lies outside farms — in dairy, poultry, food retail

“This is herbicide-tolerance through mutation breeding, not GM. There isn’t any foreign gene here,” Singh pointed out.

Both Pusa Basmati 1979 and 1985 have been bred by crossing existing popular varieties — Pusa 1121 and Pusa 1509, respectively — with ‘Robin’. The latter is a mutant line derived from Nagina 22, an upland drought-tolerant rice variety. The mutant was identified for Imazethapyr-tolerance by S Robin, a rice breeder from Tamil Nadu Agricultural University in Coimbatore.Also Read |For easy access to schemes, Govt plans 12-digit unique ID for farmers, database

Farmers in Punjab and Haryana are already adopting direct seeding of rice (DSR) in response to labour shortages and depleting water tables. This year alone, roughly 6 lakh of the total 44.3 lakh hectares area under paddy in the two states has come under DSR.

DSR cultivation is currently based on two herbicides, Pendimethalin (applied within 72 hours of sowing) and Bispyribac-sodium (after 18-20 days). As Singh pointed out, “These are costlier than Imazethapyr (Rs 1,500 versus Rs 300/acre). Imazethapyr, moreover, has a wider weed-control range and is safer, as the ALS gene isn’t present in humans and mammals. Even in the herbicide-tolerant rice, the chemical will target only the weeds.”


Transplantation in paddy typically requires about 30 irrigations, each consuming some 5 hectare-cm of water (one hectare-cm equals 100,000 litres). Puddling alone takes up about 15 hectare-cm. In all, DSR is estimated to need 30 per cent less water, save Rs 3,000 per acre in transplantation labour charges, and also 10-15 days’ time due to no nursery preparation.

But DSR’s success hinges on an effective herbicide solution — like breeding Imazethapyr-tolerant varieties.

Read Full Post »

« Newer Posts - Older Posts »