Oakes Irrigation Research
Site
Carrington Research Extension Center * North Dakota State University
P.O. Box 531, Oakes, ND 58474-0531, Voice: (701) 742-2189, FAX: (701)
742-2700, email: rgreenla@ndsuext.nodak.edu
ORIENTAL VEGETABLE PERFORMANCE TRIAL, 1996
Richard G Greenland
Last year's studies showed that oriental vegetables such as daikon radish, bok choy (also called pak choi), and baby bok choy grow well in North Dakota. Two questions that still needed to be answered were "which are the best varieties and what is the best time to plant them?" This study helped answer those questions.
Table 37. Oriental vegetable performance trial field operations at each planting time.
Table 38. Fertilizer and pest control.
Table 39. Yields and root measurements for the first planting of daikon radishes.
Table 40. Yields of the second planting of daikon radishes.
Table 41. Yields of the third planting of daikon radishes.
Table 42. Baby bok choy (pak choi) yields.
Table 43. Pak choi (bok choy) yields.
MATERIALS AND METHODS
| Soil: | Hecla sandy loam and Embden sandy loam; pH=7.3; 2.1% organic matter; soil-P and soil-K were very high; soil-S was very low. |
| Previous crop: | 1995 - onion and sweet corn; 1994 - cabbage and broccoli; 1993 - muskmelon, pop corn, and field corn. |
| Seedbed preparation: | See Table 37. |
| Planting: | Direct seeded with a Stanhay vegetable planter, see table 37 for planting dates. Pak choi and napa cabbage were spaced 7.5 inches apart in 16-inch rows, then thinned to 15 inches apart in the row. Daikon radishes were spaced 4 inches apart in 16-inch rows and later thinned to 8 inches apart in the row. Baby bok choy was planted 7.5 inches apart in 8-inch rows. It was not thinned. Seeds were placed about ½ inch deep into a flat, fine seedbed. |
| Plots: | Plots were 17 ft long by 3 ft wide. There were four 16-inch rows/bed, except Mei Qing Choi which had seven 8-inch rows/bed. There were 4 reps. |
| Fertilizer: | On April 17, broadcast 14 lbs N/acre and 70 lbs P2O5/acre as 10-50-0, 16 lbs N/acre and 19 lbs S/acre as 21-0-0-24, and 94 lbs K20/acre as 0-0-60. See table 38 for further fertilizer applications. |
| Irrigation: | Overhead sprinkler irrigation as needed. |
| Pest control: | See Table 38. |
| Harvest: | See Tables 39 to 43 for harvest dates and results. The fourth planting was killed by blight. |
RESULTS
May 1 was too early to plant daikon radishes. Even those that reached harvestable size were beginning to bolt and were of questionable quality. Some daikon radishes planted on May 1 also had more secondary roots. Mid-May is the earliest daikon radishes should be planted in North Dakota. Omny and Spring Light were the best overall varieties (especially when planted early). April Cross grew well but had a tendency to have secondary roots. April Cross is long and skinny, Omny is long and husky. Spring Light is short and fat Daebu Summer grew well when planted in July. It was short and fat. Tae Back and White Gem should not be planted in North Dakota because they bolt too readily.
Mei Qing Choi grew well planted at any date. Joi Choi had poor germination (probably a seed quality problem) but what did grow, grew well when planted at any date.Napa cabbage did not consistently form a good head. Of all the varieties planted on April 30, only Spring Flavor formed any heads at all. For those planted on June 4, head formation was inconsistent with only 20 to 30 percent of the plants forming heads. Napa planted July 10 or July 25 did not mature sufficiently for head formation.
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Table 37. Oriental vegetable performance trial field operations at each planting time.
| Planting time | Date | Operation | Purpose |
| All | April 24 April 26 |
subsoil disk |
breakup hardpan incorporate fertilizer |
| first | April 30
|
multiweed twice plant (except radishes)
multiweed twice |
incorporate fertilizer and Treflan herbicide
|
| second | June 3 June 4 June 4 |
disk multiweed twice plant |
initial tillage and incorporate insecticide incorporate herbicide and smooth seedbed |
| third | July 8 July 9 July 10 |
disk multiweed twice plant |
initial tillage and incorporate insecticide incorporate herbicide and smooth seedbed |
| fourth | July 25 July 25 July 25 |
disk multiweed twice plant |
initial tillage and incorporate insecticide incorporate herbicide and smooth seedbed |
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Table 38. Fertilizer and pest control for the oriental vegetable performance trial.
| Planting time | Fertilizer | Pest Control | ||
| date | rate | date | control | |
first |
April 29 | 35 lbs N/acre as 28-0-0 | April 30 May 1 May 2 May 15, May 31 July 9, July 12 |
Treflan (1 pt/acre) Diazinon (3 qts/acre) Dacthal (10 lbs/acre) Sevin (1.5 pts/acre) Asana (8 oz/acre) |
second |
April 29 Aug 21 |
35 lbs N/acre as 28-0-0 55 lbs N/acre as urea |
June 3 June 4 June 4 June 18 July 16, July 24 July 9, July 12, July 31 |
Diazinon (3 qts/acre) Treflan (1 pt/acre) Dacthal (8 lbs/acre) Sevin (1.5 pts/acre) Sevin (2 qts/acre) Asana (8 oz/acre) |
third |
April 29 Aug 21 |
35 lbs N/acre as 28-0-0 55 lbs N/acre as urea |
July 8 July 9 July 11 July 16, July 24 July 31 |
Diazinon (3 qts/acre) Treflan (1 pt/acre) Dacthal (8 lbs/acre) Sevin (2 qts/acre) Asana (8 oz/acre) |
fourth |
April 29 Aug 21 |
35 lbs N/acre as 28-00 55 lbs N/acre as urea |
July 25 July 25 July 25 July 31 |
Diazinon (3 qts/acre) Treflan (1 pt/acre) Dacthal (8 lbs/acre) Asana (8 oz/acre) |
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Table 39. Yields and root measurements for the first planting of daikon radishes. Planted on May 1 and harvested on June 24.
| Name | Seed source1 | Plants emerged2 | Date bolted | Roots > ½ lb | Total | |||||
| roots/A | yield | length | diameter | size | roots/A | yield | ||||
| 1000s/A | 1000s | tons/A | ------ inches ----- | oz/root | 1000s | tons/A | ||||
| April Cross | AT | 61.0 | June 24 | 27.2 | 9.6 | 12.0 | 1.74 | 11 | 51.7 | 13.0 |
| Omny | SK | 64.9 | June 24 | 21.8 | 8.6 | 11.3 | 1.90 | 12 | 46.3 | 12.5 |
| Spring Light | HN | 74.9 | June 24 | 27.2 | 9.9 | 9.0 | 1.97 | 11 | 70.8 | 15.8 |
| BN 91144 | HN | 43.7 | June 21 | Not harvested because it bolted too early | ||||||
| Dae Jin Summer | HN | 74.9 | June 16 | Not harvested because it bolted too early | ||||||
| Daebu Summer | HN | 72.1 | June 15 | Not harvested because it bolted too early | ||||||
| White Gem | HN | 51.9 | June 11 | Not harvested because it bolted too early | ||||||
| Tae Back | HN | 69.2 | June 10 | Not harvested because it bolted too early | ||||||
| LSD (0.05) | 8.2 | NS | NS | 1.5 | 0.15 | NS | NS | NS | ||
| C.V. (%) | 9 | 33 | 27 | 8 | 5 | 12 | 29 | 15 | ||
1See appendix A for
source codes.
2Rating taken on 3 June 1996. Plots were thinned after rating
was taken.
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Table 40. Yields of the second planting of daikon radishes. Planted on June 4 and harvested on July 30.
| Name | Seed source1 | Emergence rating2 | Total yield | Total roots/acre | Average size |
| 1 to 10 | tons/acre | 1000s | oz/root | ||
| April Cross | AT | 8.0 | 26.2 | 50.7 | 16.6 |
| BN 91144 | HN | 6.8 | 14.1 | 35.9 | 12.5 |
| Dae Jin Summer | HN | 9.3 | 14.9 | 55.6 | 8.6 |
| Daebu Summer | HN | 8.8 | 18.3 | 53.9 | 10.8 |
| Omny | SK | 8.0 | 27.5 | 53.4 | 16.5 |
| Spring Light | HN | 9.3 | 23.5 | 56.4 | 13.3 |
| Tae Back | HN | 8.5 | Bolted - not harvested | ||
| White Gem | HN | 7.8 | Bolted - not harvested | ||
| LSD (0.05) | 0.9 | No statistics possible on these values. | |||
| C.V. (%) | 7 | ||||
1See appendix A for
source codes.
2Emergence rating taken just before thinning on July 8. 0 = no
plants; 10 = perfect stand.
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Table 41. Yields of the third planting of daikon radishes. Planted July 10 and harvested September 23.
| Name | Seed source1 | Total yield | Total roots/acre | Average size |
| tons/acre | 1000s | oz/root | ||
| Replicated trial | ||||
| April Cross | AT | 38.4 b2 | 66.1 | 21 |
| Daebu Summer | HN | 44.5 a | 60.5 | 24 |
| Omny | SK | 35.9 bc | 56.4 | 22 |
| White Gem | HN | 30.9 c | 44.1 | 23 |
| C.V.(%) | 9 | 32 | 25 | |
| Single plots | ||||
| BN 91144 | HN | 33.2 | 42.5 | 25 |
| Spring Light | HN | 45.5 | 62.1 | 23 |
| Tae Back | HN | Bolted - not harvested | ||
1See appendix A for source codes.
2For replicated trial, values in this column followed by the same letter are not significantly different at the 0.05 level. No significant differences between values in other columns.
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Table 42. Baby bok choy (pak choi) yields. Variety grown was Mei Qing Choi.
| Plant date | Harvest date | Plants per acre | Yield tons/A | Comments |
| April 30 | June 14 | 81,700 | 5.5 | |
| June 4 | July 19 | 80,600 | 14.7 | Mei Qing Choi was too big |
| July 10 | Sept 23 | 54,500 | 20.9 | too big and old |
| July 25 | not harvested (killed by alternaria blight) | |||
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Table 43. Pak choi (bok choy) yields for 1996. Variety grown was Joi Choi.
| Plant date | Harvest date | Plants per acre | Yield tons/A | Comments |
| April 30 | Data lost | poor stand | ||
| June 4 | July 30 | 39,200 | 20.6 | stand fair |
| July 10 | Sept 23 | 27,800 | 20.6 | stand fair |
| July 25 | not harvested (killed by alternaria blight) | |||
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Go to Oakes Irrigation Research Site Variety Performance Trials
Go to Oakes Irrigation Research Site 1997 annual report