Pickling Pepper Trial, 1982

Local growers and processors could benefit by introduction of new crops into the Willamette Valley. Currently, processors of pickling peppers import their needs from more southerly growing areas. Local production has been thought to be limited by lack of adapted cultivars, poor yields, or quality problems. The following trial was undertaken to evaluate the yield potential of four pepper cultivars collected by the Steinfeld's Co., and to investigate the use of ethephon as a ripening agent for cherry type peppers.


All cultivars were seeded in a greenhouse on March 25, 1982, and transplanted to the field on May 19 on 0.91 m x 0.45 m spacing. The plot area had received a broadcast, incorporated application of 1,120 kg/ha of 10-20-10 before planting. Soil pH in the plot area averaged 5.7. Transplants were watered in with a transplant solution, diphenamid was applied for weed control at 4.5 kg/ha, and the plots were immediately irrigated by overhead sprinkler. Following establishment, plots were irrigated weekly. A sidedress application of 224 kg N/ha as calcium nitrate was made on June 15. Plots were cultivated three times during the growing season.

Plots were hand-harvested on five occasions between early August and early October. Only full-sized fruit were harvested. Only fully red-ripe fruit of cherry type peppers were harvested. On August 20, half the plots of Peto Sweet Cherry were sprayed with 0.1% ethephon at a rate of 700 liters of spray/ha. Plots were in randomized block design with four replications of each cultivar (8 reps for Peto Cherry).

Results and Discussion

Total yields ranged from 14.6 MT/ha (cherry types) to nearly 50 MT/ha for Petite Sirah, a small banana wax type (Table 1). In each case, the figures represent usable yield since rotten fruit was discarded and immature fruit was not picked. In the case of two cherry types, 5-6 MT/ha of green fruit remained at the final harvest. No fungicides were used in this trial. Fruit rot problems were insignificant for Petite Sirah and Cascabella but caused significant yield reduction for the cherry types. More than half the fruit of the cherry types was discarded at the last harvest. Rough and cracked fruit was also a problem with both cherry types. The Harris and Peto cherry types were identical for all practical purposes.

Ethephon treatment did not significantly (P?0.05) increase the total yield of Peto Sweet Cherry (Table 1), but did greatly increase yield at the first two harvests (Table 2). Thus, ethephon promoted early ripening. Ethephon had no effect on fruit size at the first two harvests, but did reduce fruit size at the final harvest (Table 3). Fruit size of the other cultivars did not vary in a consistent fashion during the harvest season.

All cultivars set fruit unevenly and multiple pickings were necessary to harvest all fruit at the proper stage of maturity (Table 4). Since the plants are brittle and easily broken, each harvest did substantial damage to the crop. The later-maturing cherry types had a more concentrated maturity but early ripening fruit did not hold well. All cultivars continued to bloom and set on fruit during the entire season.

For the cherry types, the most practical approach may be to spray with ethephon when the fruit first starts to ripen and then harvest all the ripe fruit in one or two pickings. A once-over harvest would be possible if the processor can grade out and utilize green fruit. Yields of no more than 12 MT/ha should be expected for once-over harvest.

Table 1. Total Yield and Mean Fruit Weight of Pickling Peppers               Cultivar            Total yield   Mean fruit   Comments                                 (MT/ha)       wt.(g)                                   Petite Sirah           49.9          7.9       Small, mild, banana wax,                                                 up to 10 cm long.  Cascabella             33.8          4.5       Miniature hot banana, 2.5 to                                                 5 cm, very hot when red ripe.  Harris Cherry Sweet    15.1         14.4       Mild, spherical, 2-3 cm   	                                       diam. fruit.  Peto Sweet Cherry      14.6         14.8       Mild, spherical, 2-3 cm                                                 diam. fruit.  Peto Sweet Cherry      18.9         13.7       Early ripening stimulated     & ethephonZ                                 by ethephon.           LSD (0.05)     6.1          0.6                                     ZSprayed before first harvest with ethephon.      Table 2. Yield of Ethephon-treated and Control Peto Sweet Cherry   Peppers on Each Harvest Date, 1982                                Harvest date   Peto Cherry      Peto Cherry, ethephon                             --------------MT/ha-------------------	   8/27	           1.4	                 2.9   9/10	           3.0	                 8.4  10/11             10.2                   7.6                          Table 3. Mean Fruit Weight of Peppers Picked on Each Harvest Date  Harvest                           Cultivars                        date     Petite   Cascabella    Harris     Peto     Peto Cherry +            Sirah                 Cherry    Cherry      ethephon              -------------------------g------------------------------   8/05      8.2         -           -         -            -   8/18      7.8        5.1          -         -            -   8/27      6.9        4.0        14.4      13.9	        13.6   9/10      7.4        4.5        14.6      14.9	        15.1  10/11      9.1        4.4        14.3      15.5         12.3           Table 4. Percent of Total Pepper Yield Picked on Each Harvest Date       Harvest                                     Cultivars  date               Petite   Cascabella   Harris    Peto   Peto Cherry +                      Sirah                Cherry   Cherry    ethephon                        ------------------------%---------------------------   8/5	             15	        -	    -	     -	        -   8/18	             24	       32	    -	     -	        -   8/27	             16	       20	   15	    11	       16    9/10                19        20          22       21         44   10/11                26        28          63       68         40