Evaluation of Summer Cabbage for Tolerance to Onion Thrips. Christy Hoepting & Katie Klotzbach Cornell Cooperative Extension Vegetable Program

Transcription

1 Evaluation of Summer Cabbage for Tolerance to Onion Thrips Christy Hoepting & Katie Klotzbach Cornell Cooperative Extension Vegetable Program

2 Acknowledgements Funding provided by: Cabbage Research & Development Program We wish to thank: Bejo Research Farm, Dennis Ferlito & Staff, for hosting and maintaining this trial Seed company representatives for providing seed: Don Reed (Reed s), Eijiro Nakata (Sakata), Jan vander Heide (Bejo), Tom Gordan (American Takii), George Dobson (Stokes) Jim Ballerstein, NYSAES, for growing plug transplants and helping to plant the trial

3 Introduction Objective: To evaluate summer cabbage varieties for relative tolerance and susceptibility to onion thrips and to make this information available to cabbage growers. Relative Tolerance/Susceptibility Information for Storage & Kraut Cabbage Varieties available online: From the side menu under categories, select crop production and then Cabbage and cole crops.

4 Trial Design 19 varieties, including industry standards Cheers Bravo Rinda (susceptible) Location: Bejo Research Farm, Geneva, NY Planted: June 16, 2009 Replication: 3, single row of 30 heads per replication Plant spacing: 16 inches (13 inches for XCB4204 & XCB7206) Row spacing: 30 inches Multiple harvests: 5 heads 1. Aug 25 (70 days) 2. Sep 3 (79 days) 3. Sep 9 (85 days) 4. Sep 17 (93 days) 5. Oct 6 (112 days)

5 Trial Design Insecticides for onion thrips: July 1: Warrior July 13: Entrust July 22: Warrior July 30: Warrior Sept 7: Admire Pro 2009 season: cool & wet Jun Jul Aug Sep Relative to Normal Temp Below Below Slightly Above Normal Rain Above Above Above Below

6 Evaluation Key Maturity (all marketable) Almost ready Mature Slightly past maturity Plant Color G: green B: blue P: purple Combos: first in combo is the strongest trait (i.e. GB is more green than blue, GGB is more green than GB). Estimated marketable yield Extrapolated from from total weight of 5 heads in an area 21.9 ft 2 or 19.7 ft 2 minus % unmarketable % unmarketable Rots and large head splits Small head splits Not unmarketable, an indication of maturity Split cores Not unmarketable, an indication of maturity

7 Evaluation Key Onion Thrips Damage Severity: scale of 0 to 5, see chart Depth: number of layers with damage Overall rating Very tolerant Tolerant Very susceptible Trial For each harvest, the average of all replicates for all varieties. Compare performance of individual varieties to trial average. Bolded: better than trial average Underlined: best result Not bolded: below trial average

8 Onion Thrips Severity Ratings in Cabbage Thrips Damage Rating: 0.5 Thrips Damage Rating: 1.0 Thrips Damage Rating: 2.0 Thrips Damage Rating: 2.5 Thrips Damage Rating: 4.0 Thrips Damage Rating: 5.0 Scale of 0-5: 0 = no damage; 1 = minor; 2 = below average; 3 = average; 4 = above average; 5 = very bad

9 Onion Thrips Damage on Rinda (susceptible), 2009

10 Trim Loss on a Variety

11 Onion Thrips Damage vs. Maturity Onion thrips damage: depth (# layers affected); severity (scale 0-5) Trial of All Varieties (Harvest 1-5) 70 days 79 days 85 days 93 days 112 days 2.9 hi: 7.8 lo: hi: 8.9 lo: hi: 2.9 lo: 0.1 hi: 3.6 lo: hi: 8.5 lo: hi: 3.6 lo: hi: lo: 0.1 hi: 3.2 lo: hi: 4.8 lo: hi: 3.4 lo: Aug 25 (70d)) Sep 3 (79d) Sep 9 (85d) Sep 17 (93d) Oct 6 (112d) depth severity Trend towards slightly lower onion thrips damage Aug 25 to Sep 17, as most susceptible early varieties are pulled from the mix. Damage increased slightly after that.

12 Onion Thrips Tolerance of Summer Cabbage: Entry 1. B T Benelli 4. Bravo 5. Cheers 6. FCB Adaptor 8. Bobcat 9. FCB Ultima Vantage 11. FCB Gunma 13. XCB FCB Superkraut XCB Bajonet 18. Checkmate 19. Rinda in order from best to worst Seed Source Bejo American Takii Bejo American Takii American Takii Sakata Stokes Reeds Sakata Sakata Sakata Bejo Sakata Sakata Reeds Sakata Bejo Bejo American Takii Maturity Class days 85 days days days 85 days days >100 days days days days days days days days days 70 days or less 85 days 70 days or less 70 days or less Onion Thrips Score* Onion Thrips Rating Very Tolerant Tolerant Very

13 Onion Thrips Tolerance vs. Maturity Maturity Class 70 days or less days 85 days days Entry 1. XCB Checkmate 3. Rinda (std) 4. XCB Benelli 6. Bobcat 7. FCB FCB Superkraut T Cheers 12. Bajonet 13. FCB B Gunma 16. Bravo (std) Onion Thrips Rating Very Very Very Tolerant Tolerant Very Tolerant Tolerant Very Tolerant Tolerant Generally, early maturing varieties were more susceptible to thrips Exceptions: Benelli (early very tolerant) SKT-5 (late susceptible) May be related to plant stage at time of thrips infestation. 17. FCB Ultima Vantage > 100 days 19. Adaptor Tolerant

14 Onion Thrips Damage vs. Maturity days days 3.0 FCB7339 average 3.0 FCB6335 susceptible depth (# layers damaged): severity (scale: 0-5) almost ready mature slightly past onion thrips damage: depth (# layers affected); severity (scale 0-5) almost ready mature slightly past almost ready mature1 mature2 slightly past 1 slightly past2 0.0 almost ready mature1 mature2 slightly past depth severity depth severity In this trial, we observed a slight increase in onion thrips damage from when varieties were mature to when they were slightly past maturity, but not from almost ready to mature. - especially in early maturing varieties

15 Onion Thrips Damage vs. Maturity onion thrips damage: depth (# layers affected); severity (scale 0-5) T541 almost ready Very tolerant 85 days mature past almost ready mature1 mature2 past depth severity Varieties that were very tolerant were consistently that way irregardless of maturity. B2733, T541, Benelli

16 Onion Thrips Damage vs. Maturity % large head splits Entry Checkmate FCB6335 XCB4202 Bajonet Rinda Maturity class 70 days or less days 70 days or less 85 days 70 days or less % large splits at (M) or slightly past (SP) maturity 22.7% SP 13.1% SP 10.4% SP 8.3% M 5.3% M Onion thrips rating Very Very susceptible Onions thrips damage was worse in varieties where the cabbage heads were prone to splitting (earlier maturing).

17 Onion Thrips Damage vs. Maturity No large or small splits at any harvest Entry Benelli Gunma FCB0341 Ultima Vantage Adaptor Maturity Class days days days days > 100 days Onion Thrips Rating Very Tolerant Tolerant Onions thrips damage was less in varieties where the cabbage heads did not split (also later varieties).

18 Onion Thrips Damage vs. Head Size Entry Days to maturity Largest heads in the trial: Cheers 85 days Bobcat days Bajonet 85 days Gunma days Superkraut days Smallest heads in the trial: FCB days FCB days Adaptor >100 days XCB days Head size 9.9 lb 9.5 lb 9.3 lb 9.2 lb 9.0 lb 6.4 lb 6.2 lb 6.1 lb 5.1 lb Onion Thrips Rating Tolerant Tolerant Tolerant No relationship between head size and onion thrips damage.

19 Onion Thrips Damage vs. Plant Color Entry Maturity Top 3 bluest varieties: 1. Ultima Vantage days 2. FCB days 3. Cheers 85 days Top 3 greenest varieties: 3. Gunma days 2. Bajonet 85 days 1. Rinda 70 days or less Onion Thrips Rating Tolerant Very No relationship between plant color and onion thrips damage.

20 Onion Thrips Damage vs. Plant Color Blue-green varieties: Entry Maturity Onion Thrips Rating Benellii Bobcat Superkraut 86 B2733 FCB0341 Adaptor days days days days days >100 days Very tolerant Very Tolerant Tolerant No relationship between plant color and onion thrips damage.

21 B2733 : Sept days Plant Color: GB Head Weight: 8.3 lbs Est. Marketable Yield: 41.0 ton/a Thrips Damage: Depth: 0.1 (best of 13) Severity: 0.1 (best of 13) Overall Rating: very tolerant Comments: Matured 20 days later than expected. Minor Tip Burn. 2.4% small head splits, 26.7% split cores. Bejo 74 days

22 T541 : Sept 9 85 days Plant Color: BG Head Weight: 8.0 lbs (3 rd largest of 15) Est. Marketable Yield: 39.9 ton/a (3 rd best of 15) Thrips Damage: Depth: 0.0 (best of 15) Severity: 0.0 (best of 15) Overall Rating: very tolerant Comments: 25.7% small head splits, 26.7% split cores American Takii days

23 Benelli : Sept 9 85 days Plant Color: GB Head Weight: 8.1 lbs (2 nd largest of 15) Est. Marketable Yield: 40.2 ton/a Thrips Damage: (2 nd of 15) Depth: 0.0 (best of 15) Severity: 0.0 (best of 15) Overall Rating: very tolerant Comments: matured 6 days later. 66.7% split cores Bejo 74 days

24 Internal Black Disorder (previously not described)

25 Internal Black Disorder (previously not described) New Internal Black Disorder Black Midrib

26 Internal Black Disorder (previously not described)

27 The secret to onion thrips tolerance in cabbage: what we know It s very complicated/unknown! Some varieties are very tolerant B2733, T541, Benelli Some varieties are very susceptible Rinda, Checkmate For varieties that fall in the middle, thrips damage increases as they pass optimum maturity Choose tolerant varieties when they suit your production and marketing situation