Inheritance of self-incompatibility in rutabaga (Brassica napus L. ssp. rapifera (Metzg.) Sinsk.)

Abstract

Self-incompatible and self-compatible lines of Brassica napus L. were crossed and the compatibility status of the F1 and F2 progeny assessed. Compatibility was established by measuring silique and seed set and by microscopic examination of self-pollen behaviour on the stigma and within the style of flowers. Microscopic evaluation was found to be unreliable in determining whether seed set would occur on a plant following self-pollination. The F1 data could not be interpreted because turnip mosaic virus in the greenhouse killed many plants and may have affected the compatibility reaction of the rest. Silique set data for the F2 showed one line (Z) segregated 3:1 self-incompatible to self-compatible, indicating only one locus involved. The 10:6 self-compatible to self-incompatible ratio, obtained for a second line (R) can be explained in the same manner if a dominant modifier (M), which interacts only with S-allele heteozygotes, is also present.Key words: rutabaga, Brassica napus, self-incompatibility, S alleles, genetic.

Partial self-compatibility in ‘Tombul’ and ‘Montebello’ hazelnuts

“…Less is known about the genetic control of PSC, in large part because distributions of seed set from incompatible crosses are frequently continuous, repeated pollination of a particular genotype can give variable results, and PSC genes may only be expressed at high temperatures or in the presence of certain S-alleles. Reports of simple genetic control, such as that of Ayotte et al (1985) in rutabaga (Brassica napus), are rare. Eenink (1981) demonstrated that self-pollination in witloof-chickory produced a continuous distribution of from 0 to 15 seeds per inflorescence.…”

Self-incompatibility interactions in Brassica napus

“…However, unusual results have been observed with some B. napes material (Gowers, 1979 ;Ayotte & Harney, 1985) where a reaction may appear to take place in the style itself . Also, the strongest incompatibility reactions are such that there is virtually no pollen tube growth, and absence of pollen tubes does not indicate pollen sterility.…”

Swede and turnip

“…3 ' 19 Both loci have been shown to be active in the pistil of synthetic B. napus but expression of the B. rapa locus was masked in the pollen. 31 The dominance relationships between the different 5-alleles found in swede can be reversed in pollen and pistil.…”