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Frost Injury in Sorghum Species

Caution! Members of the sorghum family – sorghum, sudangrass, and hybrid sorghum-sudangrass – contain dhurrin, a glucoside that breaks down to release hydrocyanic acid, also known as prussic acid (hydrogen cyanide, HCN). A sudden disruption of growth such as frost, drought or cutting, causes prussic acid to be released inside the plant at a more rapid rate. High prussic acid levels may be lethal to ruminants; death often occurs within 20 minutes of ingesting sorghum forage with elevated prussic acid concentrations.
 
Early fall, between the first frost and the first killing frost, is the riskiest time of year for prussic acid production in sorghum species. These warm-season grasses are very frost-sensitive. It is impossible to know by looking at them how much prussic acid is present in the plants. Below are some frequently asked questions related to managing sorghum species and frost.
 
Is it okay to harvest sorghum after a frost?
 
Wait 3-5 days after a killing frost to ensile sorghum or make baleage. Prussic acid levels will decrease with fermentation. Silage should be completely fermented before feeding (6–8 weeks).
 
I cut my sorghum, then we got a frost while it was in the swath. Will the sorghum still produce prussic acid?
 
Cut grasses don’t know they have been cut. Cellular processes, like respiration and photosynthesis, continue so long as the leaves have enough water and oxygen to keep going. While information on this specific situation is scarce, the safest option is to respect the same wait times as if the crop was hit by frost just before cutting. This will give the prussic acid time to dissipate.
 
There is frost in the forecast, and my cattle/sheep are grazing sorghum. Should I move them off the sorghum?
 
Yes. Prussic acid levels are highest just after the frost occurs. Since this is usually in the wee hours of the morning, it is generally much easier to avoid an issue by removing livestock from the sorghum before the forecasted frost.
 
Sometimes frost comes as a surprise. Immediately after a frost, remove the livestock from the pasture until it has dried out (usually 6–7 days). If new shoots develop, harvest the field as silage rather than pasture.
 
Prussic acid concentration is always higher in leaves than in stems. Because livestock preferentially graze leaves, they are more likely to be poisoned by prussic acid in a pasture situation. Lightly grazing a field will not reduce risk.
Source : Field Crop News

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Why Rob Saik is Trying to Build the World’s Most Connected Agriculture Network

Video: Why Rob Saik is Trying to Build the World’s Most Connected Agriculture Network

In a recent interview at the SeedLink Conference in Brandon, Man., Rob Saik, author, speaker, and CEO of AGvisorPRO, took a trip down memory lane, reminiscing about the beginnings of his career and what the future holds.

Graduating from the University of Alberta in 1983, Saik embarked on a journey that started in Brandon, Man. “I got a job with Elanko, got a U-Haul truck, threw everything I had into it, drove to the Victoria Inn, and lived there for three months while they tried to find an apartment for me to move into. So I started my career in Brandon,” Saik shared.

Fast forward to the present, Saik has evolved into an accomplished author and speaker, traversing the globe to engage in high-level discussions about the future of agriculture and the critical role it plays in feeding the world. Yet, despite his global presence, he finds himself back in Brandon, addressing a group of seed growers. But why? Saik emphasizes the fundamental importance of seeds, stating, “It all begins with a seed, doesn’t it?”

Reflecting on his own experiences as a farmer, Saik expresses his excitement when a planted seed germinates and evolves into a thriving crop. He underscores the significance of technology and breeding in seed development, recognizing the crucial role they play in ensuring farmers can propagate seeds, grow profitable crops, and contribute to global food security.

Saik delves into the challenges faced by the agricultural community, particularly the rapid pace of technological advancements. He believes that the key lies in connecting farmers to experts swiftly, boosting farmers’ confidence in adopting new technologies, and ensuring the timely implementation of these advancements. According to Saik, this approach is crucial for steering agriculture towards sustainability and profitability.

As Saik works on his upcoming book, tentatively titled prAGmatic, he sheds light on its central theme. “The thesis would be that I want to write a book that takes what the consumer wants, challenges what the consumer believes, and positions that against what the farmers can actually do pragmatically,” he explains. The book aims to bridge the gap between consumer expectations and the realistic capabilities of farmers, promoting sustainable intensification as the necessary path to feed the planet.

Looking ahead to 2024, Saik emphasizes the need for enhanced connectivity within the seed industry. He discusses his platform, AgvisorPro, which is designed to facilitate connections between farmers, experts, and companies in a way that transcends conventional social media platforms. Saik envisions a credible, connected agricultural network that goes beyond the noise of platforms like LinkedIn or Twitter.

In a passionate vision for the future, Saik imagines a tool for teachers that allows them to pose questions from students, answered by verified farmers and ranchers. This, he believes, would provide an authentic and valuable educational resource, connecting classrooms with individuals who truly understand the intricacies of agriculture.