Pickling Cucumber Inbred Line Development by Full-sib Family Selection II

Cucurbit Genetics Cooperative Report 7:8 (article 3) 1984

K. Lertrat and R. L. Lower
University of Wisconsin, Madison, WI 53706

One of the goals of our breeding program is the development of a commercial high-yielding mechanically harvestable hybrid cultivar. After the completion of three cycles of selection for improving fruit number per plant in two pickling cucumber populations, HSE-C3 (hardwickii semi-exotic cycle 3) and GS-C3 (gynoecious synthetic cycle 3), by S1 recurrent selection (2). We have conducted an inbred line development program by using full-sib family selection (1).

The second generation of this full-sib family selection was completed in 1983. Average fruit yield of 107 S1 x S1 (HSE-S1 x GS-S1) crosses was 2.31 fruit per plant, ranging from 0.88 to 3.72 fruit per plant (Table 1). This fruit yield was not significantly higher than the average of six check hybrids (1.45 fruit per plant). However, mean yield was higher than that for a well-adapted hybrid, ‘Calypso’. Twenty-one selfed lines from both populations (HSE-S2, and GS-S2) were selected on the basis of hybrid performance (selection intensity 20%) for further selection. Average fruit yield of the selected crosses was 3.20 fruit per plant.

Table 1. Summary of the second generation of selection, using full-sib family selection, for the inbred line development phase in HSE and GS populations.

 
Number of crosses

S1 x S1

Range

All crosses
101

2.31

0.88-3.72

Selected crossesa
21

3.20

0.90-3.74

Hybrid checksb
6

1.45

0.86-1.97

Calypso
1.87

1.80-1.97

aSelection intensity 20%.
bCheck hybrids included three monoecious cultivars (Clinton, Liberty and SMR 18) and three gynoecious hybrids (Calypso, Calico and Southern Belle).

Literature Cited

  1. Lertrat, K. and R. L. Lower. 1983. Pickling cucumber inbred line development by full-sib family selection. Cucurbit Genetics Coop. Rpt. 6:16-17.
  2. Nienhuis, J. 1982. Response to different selection procedures for increased fruit yield in two pickling cucumber populations. Ph.D. Thesis, University of Wisconsin-Madison.