Table 2.

Average effect of type and concentration of antibiotics on plating efficiency in 20-d-old protoplast cultures of different carrot accessions

Factor	Plating efficiency (% ± SE)			Mean
	Antibiotic
	Cefotaxime	Carbenicillin	Timentin
Accessiona
Dolanka	62.6 ± 3.6 a	43.1 ± 7.0 a	37.9 ± 2.5 a	49.8 ± 3.4 a
Amsterdamska	62.7 ± 1.3 a	8.9 ± 2.3 b	22.7 ± 3.3 b	31.4 ± 4.1 b
Koral	36.7 ± 3.1 b	12.5 ± 4.3 b	36.8 ± 3.8 a	28.6 ± 2.9 b
Concentration of antibioticb (mg L−1)
0	60.5 ± 7.3 a	50.1 ± 10.4 a	44.6 ± 4.7 a	52.4 ± 4.8 a
100	61.3 ± 5.9 a	40.3 ± 10.9 ab	36.0 ± 3.8 ab	46.7 ± 5.0 ab
200	57.7 ± 5.5 a	31.4 ± 10.8 abc	31.7 ± 5.2 ab	41.0 ± 5.2 bc
300	56.2 ± 6.3 a	22.7 ± 10.6 abc	30.6 ± 5.6 ab	37.1 ± 5.6 bc
400	53.0 ± 6.3 a	13.7 ± 9.4 bc	27.4 ± 5.3 ab	31.7 ± 5.6 cd
500	48.1 ± 6.9 a	3.0 ± 1.9 c	24.7 ± 5.2 b	25.3 ± 5.1 d

In each section of the table, means with the same letters did not differ significantly (P ≤ .001) within each column

^aThe means represent averages of all concentrations

^bThe means represent averages of the three accessions