The Application of Ooubled Haploid Plants to Population ... - MSpace

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and a daylnight temperature of f S/lO°C. These plants were covered wi polyethylene
isolation bags with 1 mm holes from about 1 d prior to fiowerïng until the end of the
flowering period. Plants were sprayeâ with 3 % NaCl spray every 3 d after the first
flowers were newly opened until flowering was complete. Mer each spray treatment,
flowers were left to dry and then shaken gently within the isolation bags to facilitate
self-pollination. The NaCl spray treatment was compared to bud pollination and was
found to be more time efficient with the ssme ability to overwme SI in B. tapa (Friesen.
1997). Selfed seed was hanrestecl from 52 DSC-3 and 60 Reward DH lines and was
used for the 1995 field study.
DH lines were evaluated in the field in 1995 as randomized complete blocks
(RCB) which wnsisted of two replicates with 3-m rows sown with 100 seeds per row for
each OH line. Check rows of cv. Reward were sown between each DH line to control
cornpetition between rows. DH lines were characterized for performance according to
the parameters: days to fiowenng, seed quantity, fertility index, lodging, disease index
(DI) relating to white nist (Albugo candida), days to maturity and height at maturity
(data not shown for 1995).
The days to flowering were detenined as the number of days from Men 501
of the plants had emerged until50% of the plants in a row had begun fîoweting. The
fertility index was detemined by visually rating plants in a row under field conditions
according to a scale of 1-5 where a 5 indicated the plants had pod and seed
developrnent similar to the check cv. Reward. Lodging was measured according to a
scale of 1-5 where a 5 indicated good stalk strength with uprigM growth. DI was a