TABLE 1.

Conjugal transfer of pTiC58 is most efficient on a solid surface^a

Donor density in mating mixb	Transfer frequency when mated inc:
	Liquid	Solid
1.4 × 108	9.3 × 10−5	5.8 × 10−2
1.4 × 107	1.7 × 10−4	9.1 × 10−1
2.2 × 106	2.4 × 10−4	6.5 × 10−2
1.4 × 108d	6.5 × 10−5	NAe

^aNT1(pTiC58ΔaccR) was mated with C58C1RS on solid and in liquid medium as described in the text. 

^bExpressed as CFU per square centimeter for matings on solid medium or per milliliter for matings in liquid medium. 

^cExpressed as transconjugants recovered per input donor. Values represent the averages of triplicate determinations for each mating. Colony counts at each dilution were within 10% of each other. The experiment was repeated twice, and the results of a representative experiment are presented. 

^dThe donor culture was mixed with the recipient culture immediately prior to dilution and plating on the selection medium all as described in the text. 

^eNA, not applicable.