PMR REPORT # SECTION J: CEREAL, FORAGE, AND OILSEED CROPS ICAR:

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1 PMR REPORT # SECTION J: CEREAL, FORAGE, AND OILSEED CROPS ICAR: CROP: PEST: Edible beans, cv. Stingray white bean Rhizoctonia root rot, Rhizoctonia solani Kuhn NAME AND AGENCY: GILLARD C L, SCHAAFSMA A W, HARDY D, VERNOOY L, and WILLIS, S. Ridgetown College, University of Guelph, Ridgetown, Ontario, N0P 2C0 Tel: (519) Fax: (519) cgillard@ridgetownc.uoguelph.ca TITLE: CONTROL OF SEEDLING ROOT ROT IN DRY EDIBLE BEANS WITH SEED TREATMENTS MATERIALS: (metalaxyl-m + fludioxonil, g ai/l); ICIA FS; (diazinon + captan + thiophanate methyl, 18% + 6% + 14% w/w) METHODS: Seed was treated in 1 kg lots in individual plastic bags by applying a slurry (all treatments diluted in water to the same volume of 2.3 ml per kg.) of material via a syringe to each bag. The seed was then mixed for 1 min to ensure thorough seed coverage. Beans were planted 8 June, 2001 at a seeding rate of 20 seeds per m for the white bean cultivar and 15 seeds per m for the cranberry and kidney cultivars, using a four-row cone-seeder mounted on a John Deere Max Emerge planter. Plots were 4 rows 5 m in length and spaced 0.76 m apart arranged in a RCBD with 4 replications. Root rot inoculum was applied to the centre two rows in each plot. All assessments were determined from the centre two rows. Plant emergence was assessed starting at 7 days after planting, using a 4 m length from the centre two rows of each plot. Plant emergence ratings were then adjusted to emergence as a percent of seed planted. Plant vigour, using a scale of 0-10 (10 = best plant development and 0 = poorest plant development) was assessed starting at 21 days after planting. Yield was determined from the centre two rows from each plot, with a total of 5 m harvested from each row. The harvest date was Plant maturity was determined by recording the days needed for 95% of the pods to reach physiological maturity (loss of green colour). Visual seed quality was determined using a scale of 1-5 (1 = excellent seed quality, 5 = poor seed quality). Seed weight was determined by recording the weight of 100 randomly selected seed from each plot. Yield and seed weights were adjusted to a standard storage moisture of 18%. INOCULUM: A strain of Rhizoctonia solani (86-8b) was cultured onto Potato Dextrose Agar (PDA). One kg. of hulless oats was added to each of several 4 litre plastic jugs and covered with 2% V8 Juice. Bottles were capped and left to stand for 2-3 hrs. After standing, excess liquid was poured off and the bottles autoclaved at 15 psi and 121 C for 1 hr. Autoclaving procedure was repeated after 3 d. The PDA plates of R. solani were cut up into small squares and 5-6 plugs placed in the bottles of sterile oats. The bottles were incubated for 2 wks. After 2 d of incubation there were golf ball sized chunks of inoculum present and the bottles were shaken every 2 d to ensure even distribution of inoculum. After 2 wks incubation, the inoculum was dried and weighed into 80 g packages. RESULTS: See Tables 1-3.

2 CONCLUSIONS: The Rhizoctonia inoculum provided more severe pressure than the Fusarium pressure, resulting in better differentiation between treatments. The highest plant stands occurred with APRON MAXX RTA combined with the mid or high rate of ICIA The only other treatment that resulted in greater emergence than the inoculated check was the low rate of APRON MAXX RTA. The best visual crop vigour ratings occurred with APRON MAXX RTA at the low rate, and APRON MAXX RTA combined with the mid or high rate of ICIA These treatments provided significantly better visual crop vigour ratings than the high rate of, but in most cases these treatments did not provide significantly better visual crop vigour ratings than the inoculated check. ICIA 5504 did not appear to be antagonistic to plant emergence or to visual crop vigour. APRON MAXX RTA at the low rate, and APRON MAXX RTA combined with the mid or high rate of ICIA 5504 provided significantly higher yield than the high rate of, but these treatments did not provide significantly better yield than the inoculated check. A severe drought in July and August resulted in quite high variability for yield, which limited the differentiation between treatments. Small differences in plant maturity and seed weight were detected. However, the differences between treatments were minimal, and it is believed that the differences would have very little impact on the crop agronomically. Differences in seed quality were due to harvest timing and heavy rains at harvest, rather than differences between seed treatments.

3 Table 1. Crop emergence for Stingray white beans with seed treatments for seedling disease at the Huron Research Station, Exeter, Ontario Emergence (as a percent of seed planted) Uninoculated Check 79 a 94 a 95 a 95 a 96 a 96 a Inoculated Check 13 b 43 e 45 e 34 d 34 d 33 cd 10 bcd 57 cd 65 bcd 59 bc 62 bc 54 bc 5 bcd 57 cde 54 de 35 d 34 d 31 d 2 d 67 bc 71 bc 67 b 67 b 67 b 4 cd 73 b 80 ab 68 b 66 b 66 b ICIA bcd 54 cde 57 cde 49 bcd 49 bcd 46 bcd 6.56 ml 10 bcd 55 cde 54 de 39 cd 38 d 38 cd 7 bcd 57 cde 62 cd 54 bcd 51 bcd 50 bcd 11 bc 52 de 56 cde 42 cd 41 cd 39 cd PR>F LSD (P=.05) CV

4 Table 2. Crop vigour for Stingray white beans with seed treatments for seedling disease at the Huron Research Station, Exeter, Ontario Visual Crop Vigour (1 = poor, 9 = excellent) Days After Planting... Uninoculated Check 8.3 a 8.8 a 8.5 a 9.0 a 9.0 a 9.0 a 9.0 a Inoculated Check 4.0 bcde 4.3 cd 4.8 bcd 5.3 bcd 6.8 bcd 6.8 bcd 6.8 bc 5.5 bc 5.5 bcd 6.0 bc 7.0 ab 7.8 abc 8.0 ab 7.8 ab 3.0 e 4.0 d 3.8 d 3.5 d 5.0 de 5.0 de 5.3 c 5.8 b 5.8 bc 6.3 b 6.5 b 7.5 abc 7.5 abc 7.3 ab 5.8 b 6.5 b 6.0 bc 6.8 b 8.3 ab 7.8 abc 7.8 ab ICIA bcd 5.0 bcd 5.3 bcd 5.3 bcd 6.3 cde 6.0 cde 6.3 bc 6.56 ml 3.5 de 4.8 cd 4.3 cd 5.0 bcd 5.5 de 5.3 de 5.3 c 4.8 bcde 5.0 bcd 5.0 bcd 6.3 bc 6.5 bcd 6.3 bcde 6.5 bc 3.8 cde 4.0 d 3.8 d 4.3 cd 4.5 e 4.8 e 5.0 c PR>F LSD (P=.05) CV

5 Table 3. Crop assessment for Stingray white beans with seed treatments for seedling disease at the Huron Research Station, Exeter, Ontario Crop Assessment Yield (kg ha -1) Plant Maturity Seed Weight Seed Quality Uninoculated Check 1576 a 88.6 d 18.9 b 1.3 d Inoculated Check 1004 bcd 91.0 a 21.2 a 3.3 ab 1270 ab 91.5 ab 20.6 a 1.8 cd 677 d 91.5 cd 19.3 a 3.5 ab 1168 abc 91.8 ab 20.5 a 3.0 ab 1320 ab 91.3 a 20.8 a 2.6 bc ICIA bcd 91.5 bc 20.0 a 3.6 ab 6.56 ml 904 bcd 91.0 ab 20.5 a 3.3 ab 1116 bc 91.5 a 20.9 a 4.0 a 761 cd 91.0 a 20.8 a 3.8 a PR>F LSD (P=.05) CV