First, the drought monitor indicated no real change over the last week. The area of moderate drought expanded a bit in Southwest Kansas but outside of part of the southwest portion of the state, the state is in adequate to excessive soil moisture. Temperatures are helping move the crops along, however, we are behind in maturity and harvest in most fields. On the positive side, seasonal temperatures are in the forecast the next 30 days. That translates in the mid-80’s now to the mid-70’s by mid-October. Precipitation is predicted to be slightly above normal. Normal precipitation for September and October is approximately two inches. The bottleneck for planting the 2020 wheat crop involves producers wanting to plant wheat after harvesting a summer crop. The hardest crop to follow will be grain sorghum.
One other quick note, this coming Saturday, Sept. 21, is the annual Butterfly Festival at the Wetland’s Education Center located right off K-156 at Cheyenne Bottoms. The event lasts from 9 a.m. until noon. It’s a great event for people of all ages, with or without children. Catching and tagging Monarch butterflies is just one of the many fun and unique activities and displays. You might ask why this is in an agriculture column. It’s simple – insects, especially pollinators are a key part of the environment and our food chain. We in agriculture ignore the conservation of these pollinators at our own peril. And we can, we must learn how to manage pests while protecting these vital insects.
Now, onto today’s topic.
Tolerance here has a different meaning than it does with people. In agriculture we use the terms crop tolerance and crop resistance regarding the ability of a crop variety/hybrid to cope with insects and diseases. Wheat varieties are rated by K-State each year and a comprehensive list of their tolerance and resistance to insects and diseases. You determine what possible pest issues you have, look at the list, see what varieties fit you problems and then cross-check them with yield and climatic adaption to your area. The same is true for other crops. These traits can be conferred through conventional breeding or genetic engineering (think glyphosate tolerant corn and soybeans). So what exactly are tolerance and resistance?
• Tolerance means the disease may infect the plant or the insect may injure the plant but the infection or injury won’t cause economic damage. There is a difference between injury and damage. Injury is what the disease or insect does to the plant. Damage is the effect. So you can have injury but not damage.
• Resistance means the disease cannot infect the plant or the insect cannot injure the plant. Resistance is preferred to tolerance as it is more complete but both are important options in pest control.
• One important note is in order. To achieve tolerance or resistance you normally sacrifice yield. To get something you must give up something.
• And in many cases, resistance and tolerance breakdown over time.
Dr. Victor L. Martin is the agriculture instructor/coordinator for Barton Community College. He can be reached at 620-792-9207, ext. 207.