Crop Biotechnology: a Weed Science Perspective Harold D. Coble IPM Coordinator, USDA/OPMP

My Perspective Reared on small diversified farm in 1940s-50s Very familiar with the drudgery of hand hoeing College degrees in agronomy & weed science Weed science extension & research for 30 yrs Always been a farmer at heart A proponent of IPM – USDA IPM Coordinator

Photo credit USDA/NRCS And, for many reasons, I believe in conserving our natural resources

Pest management is all about crop yield and quality preservation and ease of harvest. Photo credit USDA/NRCS

Pest Management Strategies The PAMS Approach Prevention – Cultural practices to keep pests out Avoidance – Cultural practices to avoid or resist pest impact Monitoring – What is present and how many Suppression – Kill ‘em if you need to

Pest Suppression Options Physical – Hand Weeding – Mechanical Cultivation – Other (mulches,, traps, etc.) Biological – Insects, Bacteria, Fungi, Biochemicals Chemical – Chemical Pesticides – Pheromones

Chemical Weed Control Historical non-selective chemicals (NaCl) Key to chemical use is selectivity – Development of 2,4-D in 1940s – Research programs for selective herbicides – Rapid expansion of chemical use in 1960s &70s – ~100% major crop acreage treated today

Attaining Selectivity Massive chemical screening programs Selection in crop breeding programs – Tracy soybean Non-transgenic methods – Sethoxydim-tolerant corn (tissue culture) – STS soybean Transgenic technologies (Biotech)

Growth of Biotech Acres % of Total U.S. Acres

Biotech Crop Uses % of Acres

Western Corn Rootworm Adult Photo credit USDA/ARS

Why the Rapid Adoption? Herbicide Tolerant Crops Lower cost of weed control, even with technology fees Greatly simplified control procedures Higher degree of weed control Fewer chemical applications = less trips Promotes more sustainable cultural practices – Less tillage, less compaction, narrower rows Societal aspects (pride, landowner acceptance)

Higher degree of control at lower cost Photo credit USDA/NRCS

And prevent disasters such as this Photo credit USDA/NRCS

Why the Rapid Expansion? Insect Protection (PIPs) High degree of control of target species Safety to beneficial species Human and environmental safety – Food/Feed safety – Applicator safety – Wildlife safety Simplicity of control measures

PIPs aimed at the major insect pest complexes Photo credit USDA/ARS

Plant-incorporated protectants designed to avoid harm to beneficials Photo credit USDA/ARS

What’s the Downside? Herbicide Tolerant Crops Weed species shifts if integrated approach not used – Prevention and avoidance strategies – Continued field monitoring – Alternative chemical mode of action Reduced availability of alternative MOAs Temptation to just plant and spray

Weed resistance is a fact of life Photo Craig Chism, Univ. of TN

What’s the Downside? PIPs Risk of resistance development/selection – Major concern of organic community Increased cost if populations below EIL – Protection present whether needed or not Have led to secondary pest resurgence – Stinkbugs in cotton

Tarnished Plant Bug Photo credit USDA/ARS

Where do we go from here? Tacos, Chicken feed, or Plastic?? Photo credit USDA/NRCS

Meat, Milk, or Pharmaceuticals??? Photo credit USDA/NRCS

We’ve only just begun… Photo credit USDA/NRCS