Inheritance of siliqua strength in Brassica campestris L. I. Studies of F₂ and backcross populations

Abstract

KADKOL, G. P., G. M. HALLORAN, and R. H. MACMILLAN. 1986. Inheritance of siliqua strength in Brassica campestris L. I.Studies of F2 and backcross populations. Can. J. Genet. Cytol. 28: 365-373. The inheritance of siliqua strength was studied in Brassica campestris L. using F1, F2, and backcross generations of crosses between cv. Torch (shatter susceptible) and var. Yellow Sarson and var. Brown Sarson (shatter resistant) accessions. Shatter resistance (high siliqua strength) was recessive in all crosses. Crosses involving DS-17-D (var. Brown Sarson) indicated that siliqua strength is most likely controlled by two genes that show dominant epistatic interaction. Crosses of IB-5 and B-46 (both var. Yellow Sarson) each with cv. Torch indicated the likelihood of three genes controlling siliqua strength, two of which appeared to be epistatic over the third gene when dominant. In these crosses, the multivalve character appeared to be controlled by three genes, two of which were epistatic over the third gene resulting in multivalve character when the former two were recessive. Segregation for siliqua strength in the var. Yellow Sarson crosses was not independent of segregation for multivalve character.Key words: Brassica, siliqua strength, shatter resistance, Sarson. KADKOL, G. P., G. M. HALLORAN et R. H. MACMILLAN. 1986. Inheritance of siliqua strength in Brassica campestris L. I. Studies of F2 and backcross populations. Can. J. Genet. Cytol. 28: 365-373. La transmission hkrkditaire de la fermetk des siliques a kt6 ktudike chez Brassica campestris L., en utilisant les gknkrations F1 et F2, et celles de rktrocroisements, obtenues des croisements entre le cv. Torch, susceptible aux bris, et les obtentions jaunes et brunes de Sarson, rksistantes aux bris. La rksistance aux bris, ou fermetk Clevke des siliques, fut rkcessive chez tous les croisements. Les croisements impliquant le Sarson brun DS-17-D ont indiquk que la fermetk des siliques ktait tres probablement contrblke par deux genes qui ont une interaction kpistasique dominante. Les croisements impliquant deux Sahsons jaunes, IB-5 et B-46, chacun avec le cv.Torch, ont indiquk la possibilitk que trois genes contrblent la fermetk des siliques, dont deux apparaissent kpistasiques au troisieme, lorsqu'ils sont dominants. Dans ces croisements, le caractere plurivalvulk semble etre contrblk pah trois genes, dont deux sont kpistasiques au troisieme, ce qui conduit h l'expression plurivalvulk lorsque les deux premiers sont rkcessifs. La skgrkgation pour la fermetk de la silique chez les croisements de Sarsons jaunes ne s'est pas avkrke indkpendante de la skgrkgation pour le caractere plurivalvulk.

Breeding Brassica napus for Shatter Resistance

“…In a subsequent study, Mongkolporn et al (2003) confirmed a phenotypic segregation ratio of 12:3:1 (susceptible: intermediate: resistant) in an F 2 population derived from the Torch x DS-17-D, which indicated two recessive major genes (sh1 and sh2) with dominant epistasis conferring the resistance. This supports the earlier findings of Kadkol et al (1986b). Morgan et al (2000) reported that shatter resistance in B. napus was recessive and mostly determined by additive genes.…”

“…Shatter resistance could be improved by introgressing the trait from these types and B. juncea (Kadkol 2009;Raman et al, 2011). Kadkol et al (1986b) considered the genetic variation for shatter resistance within B. napus to be limited and studied inheritance of shatter resistance (measured as siliqua strength) in B. rapa in crosses between Brown Sarson (shatter resistant) and Torch (shatter susceptible) and Yellow Sarson (resistant) and Torch (susceptible). Segregation in the F 2 generation indicated the presence of 2 to 3 recessive genes which showed dominant epistatic interaction controlling shatter resistance.…”

Physiological Constraints and Their Genetic Manipulation

“…Shatter resistance has been found to be determined by recessive alleles at two or three gene loci which appeared to interact in a dominant epistatic manner (Kadkol et al 1986b). Further biometrical analyses of variation among progenies derived by intercrossing of F 2 plants from the above cross revealed a high level of non-additive genetic variance for all measures of shatter tolerance (Kadkol et al 1986c ).…”

Identification and characterization of a proline-rich mRNA that accumulates during pod development in oilseed rape (Brassica napus L.)

“…One approach is to introduce germplasm from related species by interspecific hybridization. Related species such as Brassica nigra, B. juncea and B. campestris have been used for this purpose [1,17,27] but plants resulting from these crosses are frequently sterile and lose favourable characteristics which have to be regained by back-crossing. This is both timeconsuming and laborious.…”