ARS | Publication request: GENETIC DISTANCE AND HETEROSIS IN ONION

Submitted to: Meeting Abstract
Publication Type: Proceedings
Publication Acceptance Date: November 1, 1995
Publication Date: N/A

Technical Abstract: Onion germplasm has been systematically evaluated for neither genetic distances nor heterotic response. We generated a factorial mating design using three male-sterile F1 lines in testcrosses with a sample of related open-pollinated populations and estimated combining abilities and heterosis for bulb yield, size, storage ability, pungency, soluble solids content (SSC), and water loss after 3 months in storage. Estimates of GCA for OP populations (males) were significant (p<0.05) for yield, SSC, and bulb diameters greater than 7.5 cm. Estimates of GCA for female testers were significant for storage ability and bulb diameters less than 5.0 cm. Male-by-female interactions (estimates of SCA) were significant for SSC and storage ability. Our analyses did not reveal any storage population from which inbreds would likely combine significantly better with the male-sterile tester lines. Estimates of heterosis were most often significant for yield and SSC; less often for pungency, storage ability, and bulb size; and not significant for water loss in storage. Overall, significant GCA estimates indicate that superior yielding onion inbreds and populations may be developed using recurrent-selection strategies.