Development of field-grown potato plants derived from meristem plants multiplied with different methods

Figures & data

Table I. Mean temperature, total precipitation and total radiation from June to September in the experimental field at Saku.

	Mean temperature (°C)			Total precipitation (mm)			Total radiation (MJ m^–2 s^–1)
Month	2005	2006	2007	2005	2006	2007	2005	2006	2007
June	13.6	15.6	15.1	46.6	22.0	22.4	629	675	666
July	17.8	18.3	16.5	51.4	21.4	86.6	623	719	558
August	15.7	17.3	17.3	125.4	51.6	77.0	430	464	533
September	12.4	13.7	11.1	22.2	29.7	71.2	310	307	292
Average	14.9	16.2	15.0
Total				245.6	124.7	257.2	1992	2165	2049

Figure 1.  The dynamics of total dry mass of potato plants (a–c) and dry mass of tubers (d–f) in 2005–2007 as the mean of two varieties. Plotted as moving average over three sample times (over two in the case of the first and the last dates). Multiplication methods: MP – in vitro micro-plants; TC – tip-cuttings; SC – stem-cuttings; TP – truncated plants.

Table II. The dynamics of total dry mass of potato plants multiplied as in vitro micro-plants (MP), and differences from it for other multiplication methods: tip-cuttings (TC), stem-cuttings (SC) and truncated plants (TP) in 2005–2007.

			Difference (g m^−2)
Days after planting	Degree days	MP (g m^−2)	TC-MP	SC-MP	TP-MP	LSD05 (g m^−2)
Year 2005
19	790	28.6	8.9	10.3	13.8*	10.54
23	870	39.2	6.5	11.6	12.1	19.32
27	940	61.8	6.4	13.6	19.1	21.69
33	1030	96.9	15.5	20.6	27.1	30.63
38	1100	126.8	16.6	32.4	37.8*	37.54
44	1180	168.2	50.0	63.7	38.9	79.62
49	1270	214.2	58.2	90.7	61.2	100.89
53	1330	281.7	86.9	104.7	95.9	85.21
58	1400	398.7	63.8	84.5	93.5	102.32
65	1510	460.9	97.0	124.5	115.6	133.46
71	1610	578.2	81.3	78.1	70.1	195.7
79	1720	622.3	82.7	45.8	62.6	191.95
Year 2006
10	710	16.5	6.4	5.1	5.3
23	970	36.8	31.6*	21.5*	21.5*	13.15
30	1090	71.2	66.2*	30.8	30.4	37.08
36	1190	103.0	110.8*	35.3	34.9	47.52
40	1260	128.7	143.2*	46.8	41.1	74.00
45	1360	172.1	165.3*	36.0	59.5	73.15
50	1450	214.4	158.4*	56.9	62.7	73.88
56	1560	256.9	129.2	71.9	77.9	146.44
60	1630	288.1	143.0*	94.7	103.3*	98.15
66	1730	321.1	140.8*	96.4*	156.3*	87.14
70	1800	402.1	177.4*	90.5	159.8*	139.34
73	1840	452.4	163.4	148.1	128.3	211.07
78	1920	495.5	178.9	196.7	85.0	216.7
Year 2007
14	580	39.1	−11.0*	−18.5*	2.7	10.46
24	750	103.5	−26.4	−39.9*	9.8	30.20
31	870	187.5	−20.4	−49.0	56.1	114.66
38	980	289.1	−12.7	−31.2	97.8*	81.60
44	1070	490.1	−32.1	−71.2	73.9	167.30
51	1200	716.0	0.2	−115.9	45.4	198.66
58	1360	905.0	71.0	−109.0	70.5	232.89
63	1430	1040.6	151.9	−56.2	140.6	261.48
71	1560	1128.6	169.5	77.1	158.7	403.62
79	1650	1218.5	148.2	137.6	121.1	314.80
SD05=Least significant differences at p=0.05.
* = Significant differences (p<0.05) between multiplication methods.

Table III. The dynamics of tuber dry mass of potato plants multiplied as in vitro micro-plants (MP), and differences from it for other multiplication methods: tip-cuttings (TC), stem-cuttings (SC) and truncated plants (TP) in 2005–2007.

			Difference (g m^−2)
Days after planting	Degree days	MP (g m^−2)	TC-MP	SC-MP	TP-MP	LSD05 (g m^−2)
Year 2005
19	790	6.1	0.9	−3.7	3.7	5.45
23	870	10.8	−0.6	−2.7	2.0	7.39
27	940	18.6	1.8	−0.8	4.9	6.61
33	1030	31.9	8.1	−1.4	7.3	13.82
38	1100	43.0	13.2	1.6	10.6	23.23
44	1180	58.3	39.2	22.5	15.5	51.47
49	1270	88.6	48.4	48.2	21.1	59.29
53	1330	132.2	69.6	64.1	49.5	91.58
58	1400	241.5	44.0	35.7	29.9	58.46
65	1510	300.3	77.8	80.5	62.7	91.16
71	1610	435.1	61.2	38.4	31.7	162.35
79	1720	496.9	66.4	21.8	42.5	163.15
Year 2006
10	710	6.7	−3.1	−3.3	−0.8	4.70
23	970	16.2	6.9	1.2	4.0	7.52
30	1090	35.9	23.3*	5.7	4.0	18.03
36	1190	56.5	52.7*	11.3	1.7	34.86
40	1260	77.4	80.6*	21.7	4.0	40.12
45	1360	112.7	102.1*	12.9	15.8	58.30
50	1450	151.4	99.6*	23.5	18.7	48.09
56	1560	187.3	77.6	37.6	32.6	119.01
60	1630	216.5	95.4	59.8	59.1	102.77
66	1730	245.5	105.3*	68.7	99.4	77.92
70	1800	312.8	132.9*	63.5	93.3	110.33
73	1840	353.4	124.3	122.0	69.0	173.62
78	1920	385.6	135.6	174.4	42.0	199.31
Year 2007
14	580	7.7	0.5	−3.1*	4.4*	2.73
24	750	26.4	−7.5	−14.3*	4.0	9.78
31	870	62.7	−9.8	−30.0	21.3	48.57
38	980	116.7	−17.2	−33.6	31.9	35.50
44	1070	247.3	−41.0	−70.9	18.8	112.36
51	1200	434.8	−31.6	−131.2	2.7	171.23
58	1360	602.1	8.2	−119.0	29.5	139.48
63	1430	756.7	64.3	−119.3	65.3	139.07
71	1560	858.0	81.8	−35.9	72.6	271.88
79	1650	956.4	75.6	−34.2	42.1	290.98
LSD05 = Least significant differences at p=0.05.
* = Significant differences (p<0.05) between multiplication methods.

Figure 2.  Ratio of tuber dry mass (DM) to the total dry mass of potato plant, averaged for multiplication methods over different years (a) and for different years over multiplication methods (b). Initial points in figure (b) reflect only the data of 2007. Multiplication methods: MP – in vitro micro-plants; TC – tip-cuttings; SC – stem-cuttings; TP – truncated plants.

Table IV. Mean maximum daily dry mass increase per year and per multiplication method of total potato plants and tubers.

	Maximum increase in total dry mass			Maximum increase of tuber dry mass
Year/multiplication method	Degree days	Days after planting	Increase in mass (g m^–2)	Degree days	Days after planting	Increase in mass (g m^–2)
Year
2005	1320	52	23.4	1500	64	19.1
2006	1780	69	26.7	1780	69	23.0
2007	1280	55	38.9	1400	61	35.5
Multiplication method
MP	1350	53	25.7	1570	66	23.4
TC	1490	60	32.2	1580	66	29.5
SC	1510	61	31.4	1590	67	26.7
TP	1490	60	29.3	1490	60	23.8
MP – in vitro micro-plants; TC – tip-cuttings; SC – stem-cuttings; TP – truncated plants.

Figure 3.  Differences between multiplication methods in the total dry mass and tuber dry mass of potato plants determined relative to in vitro micro-plants multiplication method over three experimental years and two varieties. Multiplication methods: MP – in vitro micro-plants; TC – tip-cuttings; SC – stem-cuttings; TP – truncated plants. Different letters indicate significant differences (p < 0.05). Vertical bars denote 0.95 confidence intervals.

Figure 4.  Differences between years in the total dry mass and tuber dry mass of potato plants determined relative to in vitro micro-plants multiplication method over all multiplication methods and two varieties. Multiplication methods: MP – in vitro micro-plants; TC – tip-cuttings; SC – stem-cuttings; TP – truncated plants. Different letters indicate significant differences (p < 0.05). Vertical bars denote 0.95 confidence intervals.