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In this study, the resistance of selected canola genotypes to the mustard aphid Lipaphis erysimi (Kaltenbach) was investigated. Molecular characterization of plant resistance was conducted, and genetic variability was observed between the resistant (KS-75) and susceptible (Abaseen) genotypes of brassica. Three RAPD markers were identified that were associated with the resistance. This study was conducted to compare the genetic data between two genotypes (KS-75 resistant and Abaseen susceptible), with an average of 4.3 bands per primer. The amplification bands per primer ranged from 9 to polymorphic fragments of 8, with fragment sizes ranging from 450 to 1700 base pairs to 9 kilo base pairs (kbps). Amplification of the largest fragment in 9 kbps using four primers (A 1–12, B 1–12, K 1–12 and L 1–12) resulted in a mean 92 percent identity index between the first two resistant and susceptible genotypes. KS-75 resistant had the highest mean genetic diversity of 92 percent, while Abaseen susceptible had the lowest mean genetic diversity of 8 percent. Out of the three markers tested, two were found to be positively associated with aphid resistance, while one was negatively correlated. These markers can be used to help develop a pre-emptive strategy for aphid resistance in brassica species, without having to simultaneously select for yield and quality related traits.

In this study, the resistance of selected canola genotypes to the mustard aphid Lipaphis erysimi (Kaltenbach) was investigated. Molecular characterization of plant resistance was conducted, and genetic variability was observed between the resistant (KS-75) and susceptible (Abaseen) genotypes of brassica. Three RAPD markers were identified that were associated with the resistance. This study was conducted to compare the genetic data between two genotypes (KS-75 resistant and Abaseen susceptible), with an average of 4.3 bands per primer. The amplification bands per primer ranged from 9 to polymorphic fragments of 8, with fragment sizes ranging from 450 to 1700 base pairs to 9 kilo base pairs (kbps). Amplification of the largest fragment in 9 kbps using four primers (A 1–12, B 1–12, K 1–12 and L 1–12) resulted in a mean 92 percent identity index between the first two resistant and susceptible genotypes. KS-75 resistant had the highest mean genetic diversity of 92 percent, while Abaseen susceptible had the lowest mean genetic diversity of 8 percent. Out of the three markers tested, two were found to be positively associated with aphid resistance, while one was negatively correlated. These markers can be used to help develop a pre-emptive strategy for aphid resistance in brassica species, without having to simultaneously select for yield and quality related traits. [ABSTRACT FROM AUTHOR]

Both morphological characteristics and amplified fragment length polymorphism (AFLP) markers were used to validate the genetic fidelity of 1 080 field-grown Echinacea purpurea plants regenerated from leaf explants of donor T5-9. Morphological diagnosis revealed that 1 067 out of 1 080 regenerants were normal, while 13 regenerants were aberrant. AFLP analysis was further performed to assess DNA variations among donor, 43 sampled normal regenerants and all 13 aberrant regenerants. Seven primer combinations generated 471 fragments among donor and normal regenerants, of which 9 fragments were polymorphic. The same primer pairs generated 484 fragments for aberrant regenerants, of which 417 fragments were polymorphic. UPGMA clustering indicated that 42 normal regenerants and donor fell into same cluster at similarity scale of > 0.99, while all 13 aberrant regenerants and one morphologically normal regenerant comprised the other clusters. AFLP analysis indicated that these 14 regenerants are off-types.

Both morphological characteristics and amplified fragment length polymorphism (AFLP) markers were used to validate the genetic fidelity of 1 080 field-grown Echinacea purpurea plants regenerated from leaf explants of donor T5-9. Morphological diagnosis revealed that 1 067 out of 1 080 regenerants were normal, while 13 regenerants were aberrant. AFLP analysis was further performed to assess DNA variations among donor, 43 sampled normal regenerants and all 13 aberrant regenerants. Seven primer combinations generated 471 fragments among donor and normal regenerants, of which 9 fragments were polymorphic. The same primer pairs generated 484 fragments for aberrant regenerants, of which 417 fragments were polymorphic. UPGMA clustering indicated that 42 normal regenerants and donor fell into same cluster at similarity scale of > 0.99, while all 13 aberrant regenerants and one morphologically normal regenerant comprised the other clusters. AFLP analysis indicated that these 14 regenerants are off-types. [ABSTRACT FROM AUTHOR]