Cucurbit Genetics Cooperative Report 8:29-30 (Article 11) 1985
Tolla, G. E.
Campbell Institute for Research and Technology, Napoleon, OH 43545
The length/diameter ratio (L/D) of pickling cucumber fruit is important to the cucumber processing industry. For small grade size fruit (less than 27 mm dia), which are packed whole by the processing industry, a L/D of approximately 2.9 is desired. If the L/D is significantly greater than 2.9, the cucumbers bridge as they are being packed in a jar; and it is not possible to obtain the desired fruit count per jar. For larger size fruit 27 to 51 mm dia), an L/D of 2.9 to 3.2 is acceptable. The bulk of the larger diameter fruit are cut into spears or hamburger chips and the bridging associated with-small size whole pack cucumbers is not a problem.
It has been observed that for a particular cucumber variety, the L/D decreases as the diameter of a fruit increases. In discussing this observation with Dr. Todd Wehner of North Carolina State University, we agreed that neither of us were aware of any published data supporting this observation.
In our 1981 cucumber trials, we collected extensive data on L/D for the 6 grade sizes used commonly in the processing industry. L/D values for 3 cultivars common to the 3 testing locations in 1981 are presented in Table 1. Each trial location was harvested a total of 10 times and the L/D values for each size were averaged for the first 2 harvests and through all 10 harvests.
The data supports the observation that as cucumber fruits increase in diameter, the L/D decreases. It has also been generally observed that for hand picked production, the L/D within a grade size increases as the season progresses (i.e., the lowest L/D values are observed in the earliest harvests). The data collected at the Ohio location supports this observation; however, the data collected in Georgia and California do not. For all grade sizes in Georgia, the L/D values averaged through 2 harvests are greater than or equal to the L/D values averaged over all 10 harvests. For California grade sizes 32 mm or less, the L/D values averaged through 2 harvests are greater than or equal to the L/D values averaged through 10 harvests. However, for sizes 32 mm in diameter and greater, the L/D values averaged through 2 harvests are less than or equal to the L/D values averaged through 10 harvests.
The general conclusion from this data is that L/D values are influenced by grade size and environment. Therefore, in selecting a cultivar to obtain a desired L/D for a specific location, the most we can look for are general trends such as: Spear-it consistently has greater L/D values than NK811, and NK811 consistently has greater L/D values than Earlipik 14 across all locations.
Table 1. Mean L/D values for cucumber cultivars by grade size for multiple hand-pick trials at 3 locations.
|
Number of
|
Grade size (diameter range in mm)
|
||||||
| Cultivar |
harvests
|
<19
|
19-27 | 28-32 | 33-38 | 39-44 | 45-51 |
|
|
|||||||
| Earlipik 14 |
2
|
2.9 | 2.8 | 2.6 | 2.6 | 2.6 | 2.4 |
|
10
|
3.0 | 3.0 | 2.9 | 2.8 | 2.7 | 2.7 | |
| NK 811 |
2
|
2.9 | 2.9 | 2.8 | 2.7 | 2.5 | 2.4 |
|
10
|
3.2 | 3.1 | 3.1 | 2.9 | 2.9 | 2.9 | |
| Spear It |
2
|
3.0 | 2.8 | 2.8 | 2.8 | 2.8 |
—
|
|
10
|
3.2 | 3.2 | 3.1 | 3.0 | 2.9 | 2.8 | |
| Earlipik 14 |
2
|
2.9 | 2.8 | 2.8 | 2.7 | 2.7 | 2.7 |
|
10
|
3.0 | 2.8 | 2.8 | 2.7 | 2.7 | 2.6 | |
| NK 811 |
2
|
3.2 | 3.1 | 3.1 | 3.0 | 2.8 | 2.6 |
|
10
|
3.2 | 3.0 | 3.0 | 2.9 | 2.8 | 2.7 | |
| Spear It |
2
|
3.4 | 3.2 | 3.0 | 3.0 | 2.9 | 2.5 |
|
10
|
3.2 | 3.0 | 3.0 | 3.0 | 2.9 | 2.8 | |
| Earlipik 14 |
2
|
3.4 | 3.2 | 3.0 | 2.7 | 2.6 | 2.6 |
|
10
|
3.1 | 3.0 | 2.9 | 2.8 | 2.7 | 2.6 | |
| NK 811 |
2
|
3.2 | 3.1 | 3.0 | 2.7 | 2.6 | — |
|
10
|
3.2 | 3.1 | 3.0 | 2.9 | 2.8 | 2.7 | |
| Spear It |
2
|
3.5 | 3.2 | 2.8 | 2.7 | 2.2 | — |
|
10
|
3.2 | 3.1 | 3.0 | 2.9 | 2.6 | 2.6 | |