M A R C H 2 0 1 9 12 POTATO GROWER G3 more than 90% of the represented acres was eligible for recertification. Kent Sather, North Dakota Sstate Seed Department Seed Potato Director, reported that 69% of North Dakota acres that had been submitted to the post- harvest test in Florida passed the re-cer- tification eligibility requirements of 0.5% or less Mosaic. This is similar to last year, but over 10% less than 2015 and 2016. Kent Sather mentioned that Alan Shulman had cell phone pictures available showing enhanced PVY leaf symptoms. Shaun Bruggeman of C.H. Robinson had been asked to give an inside per- spective on the trucking industry. He stated that 99% of truck loads are done by carriers with less than 50 trucks. 61% of carriers are owner operated. Today, carriers have more access to information about loads available than ever before. In the last few years, more trucks have become available per load, despite the fact that we lost nearly 20% truck capac- ity during recession. There are still 12- 13% fewer trucks today than in 2007. Today there is an increase in number of owner/operators. Many one-day loads have become two-day loads. Dr. Andy Robinson, NDSU/UMN, sug- gested that recognizing herbicide injury is important. The number of herbicide injury problems seems to be increasing. They show up as poor emergence, chlorosis, necrosis, abnormal leaf growth and growth reduction, mis- shapen and malformed tubers. Exposure to herbicide can be caused by soil carryover, seed contamination, par- ticle drift and inversions, contamina- tion of spraying equipment, volatiliza- tion, misapplication, etc. Symptoms are injury to leaves immediately to a few weeks after exposure. When one finds herbicide damage, one should immediately document suspect- ed herbicide drift damage. There is information available in the NDSU Extension article WC751. People should check with their State Department of Agriculture to determine steps needed to document herbicide misapplication and determine what may be needed for a formal complaint. Because injury symptoms become less visible and herbicides are broken down over time, identification becomes more difficult. Poor or abnormal plant growth is not always caused by herbicides. Other causes of similar problems may be drought stress causing reduced plant growth, fertility stress causing discol- ored leaves. PVY causing mosaic, small leaflets, wavy leaf margins and Phosphorous acid. Tuber cracking has many causes such as environmental stress, nutritional imbal- ance, disease or genetics. It can be the result of high turgor pressure and rapid tuber growth. When seed is suspected one should take samples following guidelines such as: Use clean gloves and bag. Take multiple plant samples. If seed-borne sample tubers underground, wash away soil and dry. Label and take picture of symp- toms. Place bags on ice. Ship overnight on ice. Use a reputable laboratory. Dr. Neil Gudmestad, NDSU, gave his last talk for the International Crop Expo before his retirement. He gave an overview of his 42 years of Potato Pathology Research, indicating that a pathologist likes the potato plant because it is vegetatively propagated, making it very susceptible to the impact of diseases. All disease-causing potato pathogens can be carried either on, or in, the seed tuber. In contrast, in true seed crops less than 5% of pathogens is seed-borne. Globally there are more than 150 potato diseases, of which around 40 are of eco- nomic importance. In his research pro- gram he has worked and published on 21 potato pathogens. Since the start of his career, seven new pathogens or pathogen genotypes have been intro- duced into the USA. He mentioned that he had been blessed with very good graduate students, support staff and col- laborators. Dr. Gudmestad, worked on bacterial ring rot and stated that the detection technics had gone from monoclonal antibody to DNA hybridization to PCR. One of the highlights of his research on BRR was that he e.a. developed a real- time polymerase chain reaction (PCR) assay using the cellulase A (CelA) gene sequence as the basis for primer design for the detection of BRR. His research covered many diseases: pink rot, leak, Verticillium wilt, Black Dot, Zebra Chip, tuber necrotic viruses (PVY, TRV, PMTV) and fungicide resistance. He warned against using Endura to control early blight. He was thanked for his many years of excellent service to the industry. Dr. Nora Olsen, U of I, stated that dis- ease management in storage is an inte- grated two-pronged approach. One has to deal with field-infected tubers and one must minimize spread from dis- eased to healthy in storage. Recommendations are currently: Harvest with pulp temperatures 45-65°F. Remove field heat immediately to pro-