Previous PageTable Of ContentsNext Page

Flowering date and yield of rapeseed

E.L. Armstronga, A.L. Bernardi , L.W. Banksb and T.P. Drewc

aAgricultural Research Station, Cowra. N.S.W.
Agricultural Research & Advisory Station, Condobolin. N.S.W.
Agricultural Research Centre, Trangie. N.S.W.

Rapeseed is a more temperate crop than the spring wheats grown in N.S.W. Consequently, it is disadvantaged if flowering and pod fill fall mainly in the dry and warm months of October and November. Conditions are more favourable in August and September and flowering can be programmed to occur here by adjusting sowing time (1) and/or manipulating genotype.

Experiments evaluating a range of early flowering Brassica genotypes are being run at Cowra and Condobolin. Cowra is the more favoured rapeseed growing area (aar 620mm) while Condobolin (aar 415mm) is marginal.

Results and Discussion

1982 was one of the driest seasons on record, while 1983 was one of the best and longest seasons and results have to be interpreted accordingly.

Table 1. Days from sowing to flowering and yield (t/ha).

In 1982, yields decreased as the length taken to reach flowering increased within each Brassica species, particularly in B. napus. The reverse generally occurred in 1983. In both years and sites, B. campestris did not yield as well as the other species. B. napus yielded slightly better than B. juncea, particularly in 1983 at Cowra.

The more interesting lines were the early flowering B. napus lines RU1 and RU14. They flowered earlier than B. campestris in 1982, but later in 1983. These types offer the same advantages as B. campestris in drier areas and the potential of higher yields and oil content. They also have greater seedling vigor, improving their establishment and competition with weeds. Also, they are shorter, an aid to windrowing and harvesting.

1. Armstrong, E.L., 1985. Proc. 3rd Aust. Agron. Conf., Hobart.

Previous PageTop Of PageNext Page