Most of you probably know that Orondis Gold Potato fungicide, a co-pack containing Orondis and Ridomil (active ingredients oxathiapiprolin and metalaxyl-M), will be available this spring to suppress pink rot and Pythium leak. The registration is for in-furrow application, but pink rot usually develops at the end of the season. Will Orondis applied mid-May still be active in September? My colleagues across the border always do a good job evaluating fungicides before…
This year, the incidence of corn ear rot caused by Gibberella zeae, a.k.a Fusarium graminearum, is high in some Ontario fields. A question that has been raised recently related to corn ear rot is, “Does Fusarium graminearum infect potatoes?” The answer is YES. A survey conducted by Gary Secor from North Dakota State University in the north central United States showed the predominant causes of potato dry rot in that region were Fusarium graminearum and Fusarium sambucinum. F. graminearum is the asexual…
Recently, I attended a meeting organized by the staff of BASF to provide updates on several pesticides in the pipeline. Two products that caught my attention were Zidua and CIMEGRA. Zidua is a pre-emergence herbicide that controls redroot pigweed and suppresses lamb’s quarters. It is in the same family as dimethenamid-p (Outlook) and s-metolachlor (Dual Magnum).Andrew Robinson, a potato agronomist in North Dakota and Minnesota, has been testing Zidua for three seasons. “Zidua needs to be…
Potato Days is a spectacular event that is held every year in the Emmeloord-Joure areas of Friesland. It is a 3-day event, usually the second week in November, when the Dutch potato-breeding companies and a few companies from Germany and Denmark, open their doors to showcase new potato varieties. Tuber samples are on display, and there are brochures with information on agronomy, tuber quality and pest resistance. I have attended this event…
Oct. 20, 2018—According to Mark VanOostrum, of W.D. Potato Ltd., 95 per cent of the processing crop has been dug. This is close to the fresh market acreage harvested. The consensus among growers is yield is down and tuber size is smaller due to the hot, dry summer. Cold, wet and windy weather has made digging potatoes in October a challenge. The first snow fell in the Alliston, Ont., area on October…
Pink eye is a sporadic disorder of potato tubers that may result in a significant loss of quality after harvest. The typical symptoms are pink, slightly raised areas that are easy to see on moist, freshly dug tubers, but difficult to notice on dry, unwashed potatoes. The affected areas usually occur around the eyes and at the tuber stem end. Pink eye will dry out under cool temperatures and low humidity in…
September 29, 2018 — This week, the harvest of the long storage crop was in full swing in the Alliston area. Mother Nature has cooperated, and it was non-stop digging. Storages were filling quickly with a healthy crop. Yesterday morning, I stopped by H.J. VanderZaag storages and saw Lamokas going into storage. Karen VanderZaag was grading the potatoes and looked happy — the crop was excellent, and her job was easy! In…
Pythium leak has been showing up before harvest in a number of Ontario fields this year. Symptoms of Pythium leak at the early infection stage are moist gray or brown lesions around wounds, or near the stem end of tubers. Cut through the lesions and look for a creamy rot, which will darken from light brown to dark brown, to grey and finally black when exposed to air. The cut surface has…
Potato seed infected late in the season with Dickeya (new blackleg) usually does not show symptoms in the field before harvest nor in seed storages. This is because Dickeya requires high temperatures for the development of visible symptoms. The optimum temperature for Dickeya is above 25 C. By contrast, the old blackleg (Pectobacterium) can develop at cool temperatures (8-10 C), and symptoms are usually visible when cutting seed. I have two questions about Dickeya: If dormant infection…
The potato person who said many years ago “A potato storage is not a hospital” was absolutely right. Diseased or bruised tubers do not get better in storage. Tubers bruised at harvest are easily invaded by soft rot or Fusarium dry rot, which can cause serious economic losses in storage. Harvest management, in large part, is bruise management. Bruising also affects tuber quality significantly. In order to harvest potatoes with minimum tuber…