Callus induction, shoot proliferation and root regeneration of potato (Solanum tuberosum L.) stem node and leaf explants under long-day conditions

Figures & data

Table 1. Effects of different explant sources and plant growth regulators on callus formation.

	Plant growth regulators (mg L^−1)
Explant sources	BAP	KIN	NAA	IBA	IAA	Degree of callus formation	Texture of callus	Colour of callus
Binodal	1.0 × MS medium (control)					-	-	-
	3.0	-	2.0	-	-	++++	Compact	Dark green & brown
	3.0	-	-	2.0	-	++	Friable & loose	Green & light green
	3.0	2.0	-	-	-	+++	Compact & loose	Green & dark green
	3.0	-	-	-	2.0	+	Watery soft	Yellow & colourless
	2.0	-	3.0	-	-	++++	Compact	Dark green & brown
	-	-	3.0	2.0	-	++	Friable & loose	Green & light green
	-	2.0	3.0	-	-	+++	Compact & loose	Green & dark green
	-	-	3.0	-	2.0	+	Watery soft	Yellow & colourless
Leaf	1.0 × MS medium (control)					-	-	-
	3.0	-	2.0	-	-	+++	Compact & loose	Green & dark green
	3.0	-	-	2.0	-	++	Friable & loose	Light green & green
	3.0	2.0	-	-	-	+++	Compact	Green & dark green
	3.0	-	-	-	2.0	+	Watery soft	Yellow & colourless
	2.0	-	3.0	-	-	+++	Compact	Green & dark green
	-	-	3.0	2.0	-	++	Friable & loose	Green
	-	2.0	3.0	-	-	+++	Compact	Green & dark green
	-	-	3.0	-	2.0	+	Watery soft	Yellow & colourless

Note: No callus (-); small callus (+); moderate callus (++); massive callus (+++); quite massive callus (++++).

Table 2. The effect of plant growth regulators on callus induction parameters.

Plant growth regulators (mg L^−1)					Callus induction parameters
BAP	KIN	NAA	IBA	IAA	Days for callus induction	Callus induction percentage (%)	Diameter of callus (cm)	Weight of callus (g)
1.0 × MS medium (control)					0.00 ± 0.00 ^I	0.00 ± 0.00 ^G	0.00 ± 0.00 ^I	0.00 ± 0.00 ^I
3.0	-	2.0	-	-	8.33 ± 0.19 ^A	87.50 ± 2.02 ^A	1.90 ± 0.04 ^A	2.04 ± 0.04 ^A
3.0	-	-	2.0	-	13.92 ± 0.18 ^E	73.33 ± 2.31 ^D	1.25 ± 0.03 ^E	1.43 ± 0.04 ^E
3.0	2.0	-	-	-	11.92 ± 0.19 ^C	80.00 ± 2.41 ^BC	1.46 ± 0.03 ^C	1.70 ± 0.04 ^C
3.0	-	-	-	2.0	21.96 ± 0.52 ^G	40.00 ± 2.41 ^F	0.33 ± 0.03 ^G	0.39 ± 0.03 ^G
2.0	-	3.0	-	-	9.83 ± 0.19 ^B	83.33 ± 1.97 ^AB	1.59 ± 0.03 ^B	1.81 ± 0.05 ^B
	-	3.0	2.0	-	15.08 ± 0.25 ^F	66.67 ± 2.31 ^E	0.93 ± 0.04 ^F	1.18 ± 0.06 ^F
	2.0	3.0	-	-	12.88 ± 0.22 ^D	75.83 ± 2.08 ^CD	1.30 ± 0.03^D	1.52 ± 0.04 ^D
	-	3.0	-	2.0	24.04 ± 0.76 ^H	35.83 ± 2.69 ^F	0.25 ± 0.02 ^H	0.30 ± 0.03 ^H
F-values of plant growth regulators					3169.599**	250.6775**	2583.269**	3019.141**

Note: Means of different values shown by different letters in the same column are statistically different using Duncan's multiple range test at 0.01 level of significance. Results and standard error (± SE) were calculated from six replications (n = 6).

Figure 1. Effects of different growth regulators on callus induction of the potato cultivars Granola (a), Pasinler (b) and Caspar (c, d).

Table 3. The effect of cultivars and explant sources on callus induction parameters.

	Callus induction parameters
Sources	Days for callus induction	Callus induction percentage (%)	Diameter of callus (cm)	Weight of callus (g)
Effects of cultivars
Caspar	12.51 ± 0.79 ^A	66.11 ± 3.59 ^A	1.10 ± 0.08 ^A	1.27 ± 0.09 ^A
Pasinler	12.98 ± 0.81 ^B	60.28 ± 3.39 ^B	1.01 ± 0.07 ^B	1.18 ± 0.08 ^B
Granola	13.81 ± 0.85 ^C	54.44 ± 3.29 ^C	0.89 ± 0.07 ^C	1.01 ± 0.09 ^C
F-values of cultivars (C)	81.2271**	30.2977**	183.8778**	283.6277**
Effects of explant sources
Node	12.08 ± 0.57 ^A	64.07 ± 2.82 ^A	1.08 ± 0.06 ^A	1.27 ± 0.07 ^A
Leaf	14.13 ± 0.75 ^B	56.48 ± 2.79 ^B	0.92 ± 0.06 ^B	1.03 ± 0.06 ^B
F-values of explant sources (E)	583.7570**	38.4962**	352.0444**	697.1915**
Interaction effect
F-values of C × E	1.7689^ns	0.0229^ns	0.8778^ns	0.8709^ns
F-values of C × T	1.9617*	0.5926^ns	5.2278**	8.7088**
F-values of T × E	76.8616**	1.4485^ns	8.9194**	29.5878**
F-values of C × E × T	0.5184^ns	0.1517^ns	1.5528^ns	1.4668^ns

Note: Means of different values shown by different letters in the same column are statistically different using Duncan's multiple range test at 0.01 level of significance. Results and standard error (± SE) were calculated from six replications (n = 6). Significant at 0.05 level (*); significant at 0.01 level (**); treatments (T); not significant (ns).

Figure 2. Effects of different growth regulators on shoot regeneraton from callus (a), in vitro rooting (b) and acclimatization of potato plantlets to ex vitro conditions (c, d).

Table 4. The effect of plant growth regulators on shoot regeneration parameters from callus.

Plant growth regulators (mg L^−1)					Shoot regeneration parameters
BAP	KIN	TDZ	GA3	NAA	Shoot regeneration percentage (%)	Days for shoot induction	Shoot length (cm)	Number of shoots	Number of nodes	Number of leaves
1.0 × MS medium (control)					0.000 ± 0.00^G	0.00 ± 0.00^G	0.00 ± 0.00^G	0.00 ± 0.00^G	0.00 ± 0.00^G	0.00 ± 0.00^F
2.0	-	-	0.25	-	90.00 ± 2.09^A	14.63 ± 0.29^A	6.86 ± 0.18^A	6.42 ± 0.19^A	6.58 ± 0.20^A	6.96 ± 0.27^A
-	2.0	-	0.25	-	82.50 ± 1.83^B	17.58 ± 0.28^B	5.80 ± 0.15^B	4.79 ± 0.20^C	5.54 ± 0.17^B	5.08 ± 0.21^B
-	-	2.0	0.25	-	40.83 ± 2.25^E	28.75 ± 0.35^E	2.84 ± 0.11^E	2.25 ± 0.15^E	2.50 ± 0.15^E	2.33 ± 0.17^E
2.0	-	-	-	0.25	72.50 ± 2.02^C	19.88 ± 0.24^C	5.46 ± 0.15^C	5.13 ± 0.19^B	5.00 ± 0.20^C	4.75 ± 0.18^C
-	2.0	-	-	0.25	67.50 ± 2.35^D	22.58 ± 0.28^D	4.40 ± 0.12^D	3.71 ± 0.17^D	4.04 ± 0.14^D	3.50 ± 0.20^D
-	-	2.0	-	0.25	32.50 ± 2.35^F	31.67 ± 0.40^F	1.92 ± 0.08^F	1.63 ± 0.15^F	1.71 ± 0.14^F	2.08 ± 0.16^E
F-values of PGRs					342.03**	5511.3**	1647.5**	552.36**	591.53**	536.04**

Note: Means of different values shown by different letters in the same column are statistically different using Duncan's multiple range test at 0.01 level of significance. Results and standard error (± SE) were calculated from six replications (n = 6).

Table 5. The effect of cultivars and explant sources on shoot regeneration parameters from callus.

	Shoot regeneration parameters
Sources	Shoot induction percentage (%)	Days for shoot induction	Shoot length (cm)	Number of shoots	Number of nodes	Number of leaves
Effects of cultivars
Caspar	61.07 ± 4.31^A	18.09 ± 1.24^A	4.44 ± 0.34^A	4.29 ± 0.32^A	4.29 ± 0.33^A	4.36 ± 0.34^A
Pasinler	55.36 ± 4.14^B	19.29 ± 1.29^B	3.92 ± 0.31^B	3.59 ± 0.25^B	3.59 ± 0.30^B	3.43 ± 0.30^B
Granola	48.93 ± 4.01^C	20.52 ± 1.38^C	3.34 ± 0.27^C	3.00 ± 0.29^C	3.00 ± 0.26^C	2.80 ± 0.25^C
F-values of cultivar (C)	28.6154**	174.869**	198.912**	127.746**	105.324**	144.93**
Effects of explant sources
Node	57.38 ± 3.50^A	18.83 ± 1.04^A	4.05 ± 0.26^A	3.60 ± 0.25^A	3.81 ± 0.26^A	3.80 ± 0.26^A
Leaf	52.86 ± 3.33^B	19.76 ± 1.09^B	3.75 ± 0.25^B	3.24 ± 0.23^B	3.44 ± 0.24^B	3.26 ± 0.24^B
F-values of explant (E)	11.901**	76.6891**	44.0592**	24.5455**	25.9730**	51.050**
Interaction effects
F-values of C × E	0.1319^ns	0.4916^ns	7.1954**	1.3091^ns	1.162^ns	1.437^ns
F-values of C × T	1.1583^ns	7.3403**	8.6391**	4.4818**	3.855*	5.521**
F-values of T × E	0.3626^ns	4.8950**	2.2632*	1.000^ns	1.189^ns	2.462*
F-values of C × E × T	0.1319^ns	0.5210^ns	1.5933^ns	0.4818^ns	0.594^ns	1.554^ns

Note: Means of different values shown by different letters in the same column are statistically different using Duncan's multiple range test at 0.01 level of significance. Results and standard error (± SE) were calculated from six replications (n = 6). Significant at 0.05 level (*); significant at 0.01 level (**); treatments (T); not significant (ns).

Figure 3. Effects of 1.0 × MS medium containing NAA and IBA with GA₃ on the root induction percentage (%) (a) and days for root induction (b) of cvs. Caspar, Granola and Pasinler.

Figure 4. Effects of 1.0 × MS medium containing NAA and IBA with GA₃ on the number of roots (a) and root length (b) of cvs. Caspar, Granola and Pasinler.