- Email: [email protected]
Performance of ‘Navelina’ orange on 14 rootstocks in Northern Valencia (Spain)
Scientia Horticulturae 98 (2003) 223–232
Performance of ‘Navelina’ orange on 14 rootstocks in Northern Valencia (Spain) M.A. Forner-Giner, A. Alcaide, E. Primo-Millo, J.B. Forner* Instituto Valenciano de Investigaciones Agrarias, Apartado Oficial, 46113 Moncada, Valencia, Spain Accepted 3 December 2002
Abstract Carrizo and C-35 citranges [Citrus sinensis (L.) Osb: Poncirus trifoliata (L.) Raf.], Cleopatra mandarin (C. reshni Hort. ex Tan.), C. volkameriana Ten. & Pasq. and 10 new hybrid selections, obtained in the breeding program of rootstocks carried out in the IVIA from 1974, were tested as rootstocks for ‘Navelina’ orange under northern Valencia conditions. Yield was weighed over the first seven harvests, fruit quality was determined in the 5th and 7th crops and tree size was evaluated after the seventh harvest. Trees on C. volkameriana rootstock produced the highest cumulative yield and larger fruits. On the other hand, trees on the 02034 hybrid [Troyer citrange ðC: sinensis P: trifoliataÞ Cleopatra mandarin, selection no. 4] were the most efficient in yield per cubic meter of canopy volume and gave the higher juice content, but there were little differences between rootstocks in this last parameter. Cleopatra mandarin induced the lowest TSS/TA ratio in both harvests and the lowest peel color index. Published by Elsevier Science B.V. Keywords: Yield; Tree size; Fruit quality; Hybrid selections
1. Introduction ‘Navelina’ orange is one of the most important cultivars in Spain. In 1990, plantations totaling more than 54,000 ha of ‘Navelina’ orange were planted in Spain and production exceeded 1.1 million tonnes (MAPA, 1990). Carrizo citrange [Citrus sinensis (L.) Osb: Poncirus trifoliata (L.) Raf.] is currently the most important rootstock used in Spain. In the Valencian Community, during the 1997– 1998 season, 85.7% of nursery production was on Carrizo citrange rootstock, 3.7% on
* Corresponding author. Tel.: þ34-961-391-000; fax: þ34-961-390-240. E-mail address: [email protected] (J.B. Forner).
0304-4238/03/$ – see front matter. Published by Elsevier Science B.V. doi:10.1016/S0304-4238(02)00227-3
224
M.A. Forner-Giner et al. / Scientia Horticulturae 98 (2003) 223–232
Cleopatra mandarin (C. reshni Hort. ex Tan.) and 2.1% on C. volkameriana Ten. & Pasq. (Pina et al., 2000). Much of the soil in Spain is calcareous, frequently with more than 30% of CaCO3, and pH ranking between 7.5 and 8.5. Salinity affects several areas of Castello´ n, Valencia and Alicante (produced mainly by NaCl) and most areas of Murcia and Almerı´a provinces (produced by sulfates). Some years flooding also affects the areas near the Jucar river (Forner et al., in press). For all these reasons, trees on the rootstocks used in Spain may have some problems. Carrizo citrange is susceptible to salinity and lime-induced chlorosis (Newcomb, 1978; Forner et al., 1982). Trees on Cleopatra mandarin are tolerant to these problems (Newcomb, 1978), although they have the tendency to grow slowly for the first few years after planting and some varieties (mainly Clementines) on Cleopatra also produce lower yield and fruit size than on other rootstocks (Forner, 1996). Trees on C. volkameriana are vigorous and bear precociously, but are more susceptible to Phytophthora spp. and yield less as trees reach about 15 years (Forner, 1996). Recently some Spanish Orchards have been planted with C-35 citrange ðC: sinensis P: trifoliataÞ rootstock, it is resistant to the citrus nematode (Tylenchulus semipenetrans Cob.). and trees on this rootstock also reach a smaller size than on Troyer or Carrizo citranges (Cameron and Soost, 1986). To solve these problems, J.B. Forner began, in 1974, a program for breeding citrus rootstocks, by traditional hybridizations, in the ‘Instituto Valenciano de Investigaciones Agrarias’ (IVIA), Moncada (Valencia, Spain). The main aims of the breeding program were to obtain new rootstocks, tolerant to CTV, salinity and to lime-induced chlorosis and resistant to Phytophthora spp. (Forner and Alcaide, 1993, 1994). The present test compared trees on the most used commercial rootstocks in Spain, with C-35 citrange and 10 hybrid selections obtained in the Spanish breeding program. Two out of 10 hybrid selections used in this test, have already been released to the authorized citrus nurseries and are being registered in the European Union (Forner et al., 1997, in press) under the denomination of ‘Forner Alcaide 5’ (F&A 5) and ‘Forner Alcaide 13’ (F&A 13).
2. Materials and methods Carrizo and C-35 citranges, Cleopatra mandarin, C. volkameriana and 10 new hybrid selections, obtained in the breeding program of rootstocks carried out in IVIA from 1974 (Table 1) were tested as rootstocks for ‘Navelina’ orange. Seeds of the rootstocks were obtained from the germplasm collection of rootstocks in IVIA (the same rootstocks used in the Spanish citrus nurseries) and the original hybrids obtained in the breeding program, except C-35 citrange which was obtained from Willits and Newcomb, Arvin, CA. All nursery processes were performed in an aphid-proof greenhouse, with cooling system, temperature ranging between 18 and 27 8C and relative humidity at about 80%. Seeds were sown in the seedbed in January 1989 and seedlings were transplanted individually to plastic bags of 7l capacity in April of the same year. In September, the seedlings were grafted with the selection virus-free of ‘Navelina INIASEL 7-5’.
M.A. Forner-Giner et al. / Scientia Horticulturae 98 (2003) 223–232
225
Table 1 Rootstocks tested for ‘Navelina’ orange Code no.a Botanical namesb
02034 020349 03015
C. sinensis (L.) Osb. P. trifoliata (L.) Raf. C. reshni Hort. ex Tan. C. volkameriana Ten. & Pasq. C. sinensis P. trifoliata (C. sinensis P. trifoliata) C. reshni (C. sinensis P. trifoliata) C. reshni C. reshni P. trifoliata
03017 030113
C. reshni C. reshni
030123 030142 030146 03027 030212
C. C. C. C. C.
a b
reshni reshni reshni reshni reshni
Common name/cultivar Carrizo citrange
Cleopatra mandarin Volkamer lemon C-35 citrange Troyer citrange Cleopatra mandarin no. 4 Troyer citrange Cleopatra mandarin no. 49 Cleopatra mandarin ‘Rubidoux’ trifoliata orange no. 5 (registered in EU as Forner Alcaide 5) P. trifoliata Cleopatra mandarin ‘Rubidoux’ trifoliata orange no. 7 P. trifoliata Cleopatra mandarin ‘Rubidoux’ trifoliata orange no. 13 (registered in EU as Forner Alcaide 13) P. trifoliata Cleopatra mandarin ‘Rubidoux’ trifoliata orange no. 23 P. trifoliata Cleopatra mandarin ‘Rubidoux’ trifoliata orange no. 42 P. trifoliata Cleopatra mandarin ‘Rubidoux’ trifoliata orange no. 46 (C. sinensis P. trifoliata) Cleopatra mandarin Troyer citrange no. 7 (C. sinensis P. trifoliata) Cleopatra mandarin Troyer citrange no. 12
Codes used in the rootstock breeding program. Botanical names according to Ortiz (1986).
The substrate used, steam sterilized, was composed by siliceous sand (40%), peat moss (60%), calcium superphosphate (1.5 kg/m3), dolomite (2.22 kg/m3), CaCO3 (3 kg/m3), CuSO4 (83.6 g/m3), ZnSO4 (27.8 g/m3), MnSO4 (27.8 g/m3), FeSO4 (46.4 g/m3), H3BO3 (728 mg/m3) and (NH4)6Mo7O244H2O (370 mg/m3). Plants were irrigated, once weekly, with a nutrient solution composed of monoammonium phosphate (0.15 g/l), Ca(NO3)2 (0.67 g/l), KNO3 (0.09 g/l), CuSO4 (0.008 mg/l), ZnSO4 (0.089 mg/l), MnSO4 (1.95 mg/l), H3BO3 (0.57 mg/l) and (NH4)6Mo7O244H2O (0.036 mg/l) and V2O5 (0.0065 mg/l). An iron chelate (6% Fe2þ) was added at 0.25 g/l each 4 weeks. The budded trees were planted on 29 October, 1990, in a plot at IVIA. There was one tree on each rootstock arranged in six randomized complete blocks. Tree spacing was 5:2 m 4:5 m. One guard row was also planted around the experimental plot. The soil was sandy-loam, with 24.6% of CaCO3, 5.4% de-active calcium carbonate and pH ¼ 7:5. The plot was originally planted with oranges on sour orange rootstock. One year before planting, old trees were uprooted and the plot was prepared by removing 50 cm of topsoil, leveling the subsoil and spreading the topsoil. Standard cultural practices were used, with mechanical weed control between rows and chemical control between trees. After 3 years of culture, trees were hand pruned annually in January. Drip irrigation was installed, adjusting the frequency, according to the season of the year, from 1 (in winter) to 5 days (in summer) per week, with 40 l/tree in each irrigation. Water pH was 7.60, electrical conductivity 1.40 mS/cm, Cl 134.8 mg/l and NO3 158.0 mg/l. Fertilization was applied from the 2nd year and increased annually. The amounts applied in 2000 were: ammonium nitrate (33%) 2 kg/tree, monoammonium phosphate 0.5 kg/tree, KNO3 0.8 kg/tree, epsonite 3.6 g/tree and iron chelate 18 g/tree.
226
M.A. Forner-Giner et al. / Scientia Horticulturae 98 (2003) 223–232
In November or December, the crop of each tree was harvested and weighed. Fruit quality was determined in the 5th (1998–1999) and 7th harvests (2000–2001). After harvest, 25 fruit samples per tree were taken. The samples were weighed, fruit diameter measured and cut in a half. Rind thickness was determined with a digital caliper and juice extracted with an electric squeezer. The juice and the flesh were collected in a mesh bag (40 filaments/cm) and juice extracted by hand squeezing the bag until no juice remained. The flesh left in the bag was about 8% of the total weight of the fruit. Solids (TSS) were determined by an Atago digital temperature-compensated refractometer, model PR-1. Acids (TA) were determined by titration with 0.1 N NaOH using a Brand digital burette, model II and a solution of 1% phenolphthalein in ethanol as indicator. In the 5th crop, peel color index was determined before cutting the fruits, with a Minolta colorimeter, model CR-300, taking three measurements per fruit at the equator level. Tree size was evaluated in January 2001 using the formula V ¼ 0:524hd 2 that is one-half of a prolate spheroid and where h is the tree height and d the average of two diameters N–S and E–W (Turrell, 1946). The data were tested using the MSTAT program for analysis of variance (ANOVA 2) and Duncan’s multiple range test at P ¼ 0:05 for the mean separation.
3. Results and discussion Trees grew normally throughout and none were affected by Phytophthora spp. or other known pathogens. Neither were iron chlorosis nor salinity symptoms observed. 3.1. Yield Trees on nine rootstocks out of the 14 tested, yielded their first fruits in 1994, 4 years after planting in the field (Table 2). C. volkameriana produced the highest crop and no fruits developed on trees of Cleopatra mandarin, Carrizo citrange and selections 02034, 03017 and 030142. During the 1995/1996 season, all trees produced fruits, but no significant differences were detected between rootstocks. In the following harvests, the yield increased until the 1999/2000 season, which may be considered the first season of full production. Trees on C. volkameriana rootstock produced the highest cumulative yield (Table 2), followed, with no significant differences, by trees on F&A 5, F&A 13 and 030123 rootstock selections. The cumulative yield of trees on Carrizo citrange and Cleopatra mandarin was lower than the average. In Spain, it is usual that scaffold branches are formed next to the bud union and, therefore, it is difficult to measure the trunk cross-sectional area. In these conditions, the canopy volume is a better parameter to evaluate tree size. The larger trees, measured as canopy volume (m3), were found on the 03017 rootstock selection, with no significant differences compared with trees on Volkamer lemon and the selections 030123 and 030146 (Table 2). The smallest trees were found on the 02034 rootstock selection without significant difference with trees on 03027, 020349 and F&A 13 hybrid rootstock selections. The highest yield efficiency was shown by trees on the 02034 rootstock selection, followed by F&A 13, with no significant differences (Table 2). The lower yield efficient
Table 2 Yield, tree size and yield efficiency of ‘Navelina’ orange on 14 rootstocks, planted in October 1990a Yield (kg/tree)a
Rootstocks
1994/1995 1995/1996 1996/1997 1997/1998 1998/1999 1999/2000 2000/2001
F&A 13 030123 03017 030146
020349 030212 030142 02034 03027 Mean CV (%) a
Volkamer lemon Cleopatra ‘Rubidoux’ trifoliata no. 5 Cleopatra ‘Rubidoux’ trifoliata no. 13 Cleopatra ‘Rubidoux’ trifoliata no. 23 Cleopatra ‘Rubidoux’ trifoliata no. 7 Cleopatra ‘Rubidoux’ trifoliata no. 46 C-35 citrange Troyer Cleopatra no. 49 Cleopatra mandarin Cleopatra Troyer no. 12 Cleopatra ‘Rubidoux’ trifoliata no. 42 Troyer Cleopatra no. 4 Carrizo citrange Cleopatra Troyer no. 7
Yield efficiency (kg/m3)
Tree height (m)
Canopy volume (m3)
282.32 a 259.85 ab
1.97 bc 1.88 cd
7.13 a–c 5.71 b–e
41.55 c–e 46.30 b–d
254.15 a–c
1.65 d–g
4.88 d–f
54.59 ab
1.50 a 0.24 b
1.87 a 2.30 a
13.84 ab 14.09 ab
31.02 bc 37.43 ab
66.08 a 58.31 ab
94.33 a 77.58 b
0.17 b
2.57 a
16.52 a
46.15 a
52.86 bc
70.44 b–d 65.45 a–d
0.09 b
1.93 a
13.27 ab
29.26 bc
54.19 a–c 67.83 b–e 71.68 ab
238.26 a–d
1.85 c–e
6.44 a–d
37.69 c–g
0.00 b
1.70 a
4.18 de
32.56 bc
51.97 bc
0.19 b
1.73 a
8.23 b–e 27.44 bc
0.70 0.42 0.00 0.16 0.00
0.16 2.67 1.16 2.33 1.33
b b b b b
0.00 b 0.00 b 0.10 b 0.25 263
a a a a a
3.13 a 1.47 a 2.43 a 1.91 115
12.27 11.72 4.50 8.23 3.31
a–c a–d c–e b–e e
30.32 28.66 27.92 26.42 31.01
bc bc bc bc bc
73.68 a 69.91 ab
Tree size
76.45 bc
67.85 a–c
234.71 b–d
2.22 ab
8.07 a
29.81 fg
45.82 b–e 75.45 bc
56.86 a–d
215.72 b–e
2.30 a
7.69 ab
29.47 fg
43.93 47.19 41.73 41.92 37.79
53.98 54.14 60.75 59.58 50.87
213.18 204.37 195.89 195.74 187.25
1.80 1.50 1.84 1.73 1.73
5.53 4.41 5.89 5.13 5.37
39.40 48.15 34.63 43.99 35.22
c–e b–d c–e c–e de
70.61 59.57 59.82 57.09 62.93
b–d d–f d–f d–f c–f
b–d b–d a–d a–d cd
c–f d–f d–f d–f ef
c–e fg c–e c–f c–f
c–e d–f b–e c–e c–e
c–f bc e–g b–e d–g
6.97 b–d 28.78 bc 2.17 e 24.78 bc 4.50 de 22.56 c
44.87 c–e 50.54 f 36.84 de 60.16 d–f 33.53 e 54.41 ef
47.82 d 51.24 cd 49.45 cd
182.11 ef 176.65 ef 166.99 f
1.40 g 1.93 cd 1.57 e–g
3.08 f 6.47 a–d 4.09 ef
59.11 a 27.35 g 42.39 c–e
8.84
30.31
46.93
66.94
59.52
214.80
1.81
5.71
40.69
35
21
17
23
16
12
27
21
67
M.A. Forner-Giner et al. / Scientia Horticulturae 98 (2003) 223–232
F&A 5
Cumulative yield (kg/tree)
Mean separation within columns by Duncan’s multiple range test at P 0:05.
227
228
M.A. Forner-Giner et al. / Scientia Horticulturae 98 (2003) 223–232
trees were those grafted on Carrizo citrange, 030146, 03017, Cleopatra mandarin and 030142 in ascending order and with no significant differences between them. Trees on 020349 and on F&A 5 selections had also a good yield efficiency. 3.2. Fruit quality As most fruits are destined for fresh consumption, fruit size, juice content and TSS/TA are of great importance in Spain. The Commission Regulation (EC) no. 1799/2001 of 12 September 2001, established as a marketing standard for ‘Navelina’ orange, a minimum juice content of 35% and a minimum fruit size, determined as the diameter of the equatorial section of 53 mm. Nevertheless, the best commercial diameters range between 73 and 96 mm with a weight between 200 and 300 g/fruit. The Spanish regulations for the season 2001–2002, establish that ‘Navelina’ orange and other early ripening varieties can be exported when the TSS/TA ratio reaches 6.5. There were differences between rootstocks and their effects on the external parameters of fruit quality (Table 3). Volkamer lemon produced the larger fruits in both harvests. In the 5th crop, trees on Volkamer lemon and C-35 citrange produced the heaviest fruits, but without significant difference with Carrizo citrange and the 02034, 020349, 030123, 030142 and 030212 hybrid selections. In the 7th crop, Volkamer lemon also produced the heaviest fruits although there were no significant differences with C-35 citrange and the 030123 and 030142 selections. The smallest fruits were from the 03027 selection in the 5th harvest. In the 7th crop, the 030146 selection produced the smallest fruits, without significant differences with the 03027 and F&A selections, and trees on F&A 13 developed fruits with the lowest weight, no differences were detected compared with most of the other rootstocks tested. Fruits from trees on C-35 citrange, C. volkameriana and the 02034 selection had the thickest rind in the 5th crop, whereas the trees on Cleopatra mandarin produced the thinnest, there were small differences between rootstocks. In the 7th crop, fruits from trees on Volkamer lemon had the thicker rind and the 030113 selection the thinnest, small differences were also found between rootstocks (Table 3). Minor differences were noticed between rootstocks, for both harvests, in most of the internal parameters determined and in the peel color (Table 4). Peel color index in fruits of trees on Cleopatra mandarin rootstock were significantly lower and no differences were shown in other rootstocks. Trees on the 020349 rootstock selection, in the 5th crop, and on Volkamer lemon in the 7th, had the lower juice content, but small differences between rootstocks were detected in both harvests. In both the crops, fruits of trees on Cleopatra mandarin showed the lowest TSS/TA ratio, although without significant differences with the 02034 and 030212 selections. For this reason, these rootstocks can be recommended only for cultivars for midseason o late harvest time. In the 5th crop, the higher TSS/TA ratio was determined for fruits on the 030142 rootstock selection, without significant differences with Carrizo and C-35 citranges, and the 030113 and 03027 selections. The results were similar in the 7th crop, but a higher ratio was found in the 03017 selection with no significant differences with Carrizo and C-35 citranges, Volkamer lemon and 020349, 030142 and 03027 selections (Table 4).
Rootstocks
02034 020349 F&A 5 03017 F&A 13 030123 030142 030146 03027 030212 Mean CV (%) a
Carrizo citrange Cleopatra mandarin Volkamer lemon C-35 citrange Troyer Cleopatra no. 4 Troyer Cleopatra no. 49 Cleopatra ‘Rubidoux’ trifoliata Cleopatra ‘Rubidoux’ trifoliata Cleopatra ‘Rubidoux’ trifoliata Cleopatra ‘Rubidoux’ trifoliata Cleopatra ‘Rubidoux’ trifoliata Cleopatra ‘Rubidoux’ trifoliata Cleopatra Troyer no. 7 Cleopatra Troyer no. 12
no. no. no. no. no. no.
5 7 13 23 42 46
5th crop (data: 23 November 1998)
7th crop (data: 11 December 2000)
Fruit weight (g)
Fruit diameter (mm)
Rind thickness (mm)
Fruit weight (g)
Fruit diameter (mm)
Rind thickness (mm)
229.53 212.72 242.77 242.96 223.62 223.53 214.55 203.56 209.84 226.25 224.03 206.49 199.48 231.87
77.0 75.3 79.0 78.3 76.1 75.9 75.1 73.8 73.8 76.5 76.3 74.0 73.3 77.4
4.52 4.14 4.79 4.87 4.69 4.28 4.46 4.19 4.21 4.51 4.34 4.35 4.47 4.28
228.81 208.90 272.96 240.84 229.97 236.78 234.25 231.20 201.64 258.77 252.75 231.55 207.58 232.07
77.2 75.9 82.2 78.6 76.9 78.7 77.9 77.9 74.2 80.5 79.9 64.7 75.0 78.2
5.78 5.26 5.97 5.56 5.28 5.36 5.38 5.40 5.04 5.63 5.06 5.39 5.14 5.06
a–c b–d a a a–d a–d b–d cd b–d a–d a–d b–d d ab
220.80
75.8
9
3
a–c b–d a ab a–d a–d b–d cd cd a–d a–d cd d ab
4.44 6
bc d ab a ab cd b–d cd cd bc cd cd b–d cd
233.44 11
b–d cd a a–c b–d b–d b–d b–d d ab ab b–d cd b–d
a a a a a a a a ab a a b ab a
77.0
5.38
11
8
ab b–d a a–d b–d b–d b–d b–c d a–c cd b–d cd cd
M.A. Forner-Giner et al. / Scientia Horticulturae 98 (2003) 223–232
Table 3 Fruit quality of ‘Navelina’ orange on 14 rootstocks: external parametersa
Mean separation within columns by Duncan’s multiple range test at P 0:05.
229
230
Rootstocks
02034 020349 F&A 5 03017 F&A 13 030123 030142 030146 03027 030212 Mean CV (%) a
Carrizo citrange Cleopatra mandarin Volkamer lemon C-35 citrange Troyer Cleopatra no. 4 Troyer Cleopatra no. 49 Cleopatra ‘Rubidoux’ trifoliata Cleopatra ‘Rubidoux’ trifoliata Cleopatra ‘Rubidoux’ trifoliata Cleopatra ‘Rubidoux’ trifoliata Cleopatra ‘Rubidoux’ trifoliata Cleopatra ‘Rubidoux’ trifoliata Cleopatra Troyer no. 7 Cleopatra Troyer no. 12
5th crop (data: 23 November 1998)
no. no. no. no. no. no.
5 7 13 23 42 46
7th crop (data: 11 December 2000)
Juice content (%)
Soluble solids (%)
TSS:TA
55.93 56.26 53.88 55.40 56.36 51.46 55.11 56.19 56.35 55.86 55.47 54.08 54.96 55.42
11.42 10.56 10.40 11.10 11.57 10.90 11.18 10.95 10.63 10.87 11.05 10.77 11.27 10.63
8.89 7.25 8.98 9.07 7.70 8.62 8.23 8.62 8.89 8.30 9.36 8.14 8.92 7.68
55.20 5
a a ab a a b a a a a a ab a a
ab cd d a–d a a–d a–c a–d cd a–d a–d b–d a–c cd
10.95 5
Mean separation within columns by Duncan’s multiple range test at P 0:05.
8.48 6
a–c f ab ab ef b–d de b–d a–c cd a de ac ef
Peel color index 7.96 3.68 7.37 6.90 7.01 8.12 8.35 7.50 6.53 7.75 8.02 7.08 7.94 6.47 7.19 21
a b a a a a a a a a a a a a
Juice content (%)
Soluble solids (%)
TSS:TA
52.14 53.73 51.21 53.12 54.81 51.16 53.30 52.05 52.05 53.67 53.56 51.94 52.29 52.43
13.25 12.08 12.55 13.02 12.83 12.78 12.82 12.57 12.73 12.58 12.83 12.93 12.93 12.32
10.81 8.47 11.17 11.76 9.53 11.15 10.50 12.05 10.62 10.63 11.81 10.42 11.51 9.57
52.74 3
bc ab c a–c a c a–c ab bc ab ab bc bc bc
12.73 5
a c a–c ab a–c a–c a–c a–c a–c a–c a–c ab ab bc
10.72 9
a–d e a–c a–c de a–c b–d a b–d b–d ab cd a–c de
M.A. Forner-Giner et al. / Scientia Horticulturae 98 (2003) 223–232
Table 4 Fruit quality of ‘Navelina’ orange on 14 rootstocks: internal parameters and peel colora
M.A. Forner-Giner et al. / Scientia Horticulturae 98 (2003) 223–232
231
Total soluble solids were higher on the 02034 rootstock and lower on Volkamer lemon rootstock, for the 5th crop and higher on Carrizo citrange and lower on Cleopatra mandarin for the 7th crop, without significant differences compared to most of the rootstocks tried (Table 4).
4. Conclusions F&A 5 and F&A 13 selections are hybrids of Cleopatra mandarin P: trifoliata. Both are resistant to citrus tristeza virus (CTV) (Forner and Alcaide, 1997; Forner et al., in press). Moreover, F&A 5 is resistant to the citrus nematode T. semipenetrans Cob. (Verdejo-Lucas et al., 1997, 2000), less susceptible to lime-induced chlorosis, than Carrizo citrange and has a good tolerance to salinity and flooding (Forner and Alcaide, 1997). The F&A 13 selection is susceptible to lime-induced chlorosis like Carrizo citrange, but has an excellent tolerance to salinity and flooding (Forner et al., in press). The results obtained in this test show that, in addition to the characteristics described, the selections F&A 5 and F&A 13 have an excellent yield efficiency and fruit quality. As a whole, both selections have better performance than the rootstocks used at present in Spain. F&A 5 is soon going to be used commercially in Spanish citrus nurseries. The 02034 selection is tolerant to CTV (unpublished data) and seems interesting because of its tree size, yield efficiency and fruit quality. It has also good tolerance to calcareous soils, although it is sensitive to citrus nematode (Verdejo-Lucas et al., 1997). The low TSS/ TA ratio obtained in this test, can be interesting for cultivars of mid or late picking season. The 03017, 030123 and 030142 produced low yield efficiency in this trial. Nevertheless, it may be interesting to include these rootstock selections in other tests because they are resistant to CTV (unpublished data) and the citrus nematode (Verdejo-Lucas et al., 1997, 2000) and have good tolerance to calcareous soils in the preselection trials. None of the other hybrid selections tested (020349, 030146, 03027 and 030212) can be considered as interesting for commercial use with ‘Navelina’ scions. C-35 citrange performed well in this test, but in other trials still in progress (unpublished data) showed more susceptibility to lime-induced chlorosis than Carrizo citrange.
Acknowledgements Thanks are given to Dr. E.A. Carbonell for his advice on the statistical analysis. This work was financed by the Instituto Nacional de Investigacio´ n y Tecnologı´a Agraria y Alimentaria (INIA), grants no. 8127, SC94-037-C2-1 and SC98-103-C2-1 and the Instituto Valenciano de Investigaciones Agrarias. References Cameron, J.W., Soost, R.K., 1986. C35 and C32: citrange rootstocks for citrus. HortScience 21 (1), 157–158. Forner, J.B., 1996. Perspectivas en la utilizacio´ n de patrones en citricultura. In: Ayuntamiento de Nules (Ed.), 1995. II Congreso de Citricultura de La Plana. 23–25 de marzo de 1995, Nules, Castello´ n, pp. 29–41.
232
M.A. Forner-Giner et al. / Scientia Horticulturae 98 (2003) 223–232
Forner, J.B., Alcaide, A., 1993. La mejora gene´ tica de patrones de agrios tolerantes a tristeza en Espan˜ a: 20 an˜ os de historia (I). Levante Agrı´cola 325, 261–267. Forner, J.B., Alcaide, A., 1994. La mejora gene´ tica de patrones de agrios tolerantes a tristeza en Espan˜ a: 20 an˜ os de historia (II). Levante Agrı´cola 329, 273–279. Forner, J.B., Alcaide, A., 1997. Nuevos patrones de agrios (I): Hı´brido ‘Forner–Alcaide no. 5’. Levante Agrı´cola 341, 301–303. Forner, J.B., Alcaide, A., Verdejo Lucas, S., Sorribas, F.J., 1997. New hybrids as citrus rootstocks in Spain. In: Manicom, B., Robinson, J., F du Plesis, S., Joubert, P., L van Zyl, J., du Preez, S. (Eds.), 1996 Proceedings of the International Society Citriculture, vol. I, May 12–17, 1996, Sun City, South Africa, pp. 167–170. Forner, J.B., Forner, M.A., Alcaide, A., Verdejo Lucas, S., Sorribas, F.J., 2003. New hybrid citrus rootstocks released in Spain. In: Proceedings of the IX International Congress, December 3–7, 2000. International Society of Citriculture, Orlando, FL, in press. Forner, J.B., Aparicio, M., Alcaide, A., Giner, J., Pina, J.A., Sala, J., 1982. Present status of citrus rootstocks in Spain. In: Matsumoto, K. (Ed.), 1996 Proceedings of the International Society Citriculture, vol. 1, November 9–12, 1981, Tokyo, Japan, pp. 106–109. Ministerio de Agricultura, Pesca y Alimentacio´ n (MAPA), 1990. Anuario de estadı´stica Agraria. Madrid. Newcomb, D.A., 1978. Selection of rootstocks for salinity and disease resistance. In: Grierson, N. (Ed.), 1977 Proceedings of the International Society Citriculture, vol. II, May 1–8, 1977, Orlando, FL, pp. 117–120. Ortiz, J.M., 1986. Nomenclatura bota´ nica de los cı´tricos. Fruits 41 (3), 199–209. Pina, J.A., Sevillano, J.J., Polo, A., 2000. Plantas de vivero de cı´tricos en la Comunidad Valenciana. Comunidad Valenciana Agraria 15, 23–27. Turrell, F.M., 1946. Tables of Surfaces and Volumes of Spheres and of Prolate and Oblate Spheroids and Spheroidal Coefficients. University of California Press, Berkeley. Verdejo-Lucas, S., Sorribas, F.J., Forner, J.B., Alcaide, A., 1997. Screening of hybrid citrus rootstocks for resistance to Tylenchulus semipenetrans Cobb. HortScience 32 (6), 1116–1119. Verdejo-Lucas, S., Sorribas, F.J., Forner, J.B., Alcaide, A., 2000. Resistance of hybrid citrus rootstocks to a Mediterranean biotype of Tylenchulus semipenetrans Cobb. HortScience 35, 269–273.
Performance of ‘Navelina’ orange on 14 rootstocks in Northern Valencia (Spain) M.A. Forner-Giner, A. Alcaide, E. Primo-Millo, J.B. Forner* Instituto Valenciano de Investigaciones Agrarias, Apartado Oficial, 46113 Moncada, Valencia, Spain Accepted 3 December 2002
Abstract Carrizo and C-35 citranges [Citrus sinensis (L.) Osb: Poncirus trifoliata (L.) Raf.], Cleopatra mandarin (C. reshni Hort. ex Tan.), C. volkameriana Ten. & Pasq. and 10 new hybrid selections, obtained in the breeding program of rootstocks carried out in the IVIA from 1974, were tested as rootstocks for ‘Navelina’ orange under northern Valencia conditions. Yield was weighed over the first seven harvests, fruit quality was determined in the 5th and 7th crops and tree size was evaluated after the seventh harvest. Trees on C. volkameriana rootstock produced the highest cumulative yield and larger fruits. On the other hand, trees on the 02034 hybrid [Troyer citrange ðC: sinensis P: trifoliataÞ Cleopatra mandarin, selection no. 4] were the most efficient in yield per cubic meter of canopy volume and gave the higher juice content, but there were little differences between rootstocks in this last parameter. Cleopatra mandarin induced the lowest TSS/TA ratio in both harvests and the lowest peel color index. Published by Elsevier Science B.V. Keywords: Yield; Tree size; Fruit quality; Hybrid selections
1. Introduction ‘Navelina’ orange is one of the most important cultivars in Spain. In 1990, plantations totaling more than 54,000 ha of ‘Navelina’ orange were planted in Spain and production exceeded 1.1 million tonnes (MAPA, 1990). Carrizo citrange [Citrus sinensis (L.) Osb: Poncirus trifoliata (L.) Raf.] is currently the most important rootstock used in Spain. In the Valencian Community, during the 1997– 1998 season, 85.7% of nursery production was on Carrizo citrange rootstock, 3.7% on
* Corresponding author. Tel.: þ34-961-391-000; fax: þ34-961-390-240. E-mail address: [email protected] (J.B. Forner).
0304-4238/03/$ – see front matter. Published by Elsevier Science B.V. doi:10.1016/S0304-4238(02)00227-3
224
M.A. Forner-Giner et al. / Scientia Horticulturae 98 (2003) 223–232
Cleopatra mandarin (C. reshni Hort. ex Tan.) and 2.1% on C. volkameriana Ten. & Pasq. (Pina et al., 2000). Much of the soil in Spain is calcareous, frequently with more than 30% of CaCO3, and pH ranking between 7.5 and 8.5. Salinity affects several areas of Castello´ n, Valencia and Alicante (produced mainly by NaCl) and most areas of Murcia and Almerı´a provinces (produced by sulfates). Some years flooding also affects the areas near the Jucar river (Forner et al., in press). For all these reasons, trees on the rootstocks used in Spain may have some problems. Carrizo citrange is susceptible to salinity and lime-induced chlorosis (Newcomb, 1978; Forner et al., 1982). Trees on Cleopatra mandarin are tolerant to these problems (Newcomb, 1978), although they have the tendency to grow slowly for the first few years after planting and some varieties (mainly Clementines) on Cleopatra also produce lower yield and fruit size than on other rootstocks (Forner, 1996). Trees on C. volkameriana are vigorous and bear precociously, but are more susceptible to Phytophthora spp. and yield less as trees reach about 15 years (Forner, 1996). Recently some Spanish Orchards have been planted with C-35 citrange ðC: sinensis P: trifoliataÞ rootstock, it is resistant to the citrus nematode (Tylenchulus semipenetrans Cob.). and trees on this rootstock also reach a smaller size than on Troyer or Carrizo citranges (Cameron and Soost, 1986). To solve these problems, J.B. Forner began, in 1974, a program for breeding citrus rootstocks, by traditional hybridizations, in the ‘Instituto Valenciano de Investigaciones Agrarias’ (IVIA), Moncada (Valencia, Spain). The main aims of the breeding program were to obtain new rootstocks, tolerant to CTV, salinity and to lime-induced chlorosis and resistant to Phytophthora spp. (Forner and Alcaide, 1993, 1994). The present test compared trees on the most used commercial rootstocks in Spain, with C-35 citrange and 10 hybrid selections obtained in the Spanish breeding program. Two out of 10 hybrid selections used in this test, have already been released to the authorized citrus nurseries and are being registered in the European Union (Forner et al., 1997, in press) under the denomination of ‘Forner Alcaide 5’ (F&A 5) and ‘Forner Alcaide 13’ (F&A 13).
2. Materials and methods Carrizo and C-35 citranges, Cleopatra mandarin, C. volkameriana and 10 new hybrid selections, obtained in the breeding program of rootstocks carried out in IVIA from 1974 (Table 1) were tested as rootstocks for ‘Navelina’ orange. Seeds of the rootstocks were obtained from the germplasm collection of rootstocks in IVIA (the same rootstocks used in the Spanish citrus nurseries) and the original hybrids obtained in the breeding program, except C-35 citrange which was obtained from Willits and Newcomb, Arvin, CA. All nursery processes were performed in an aphid-proof greenhouse, with cooling system, temperature ranging between 18 and 27 8C and relative humidity at about 80%. Seeds were sown in the seedbed in January 1989 and seedlings were transplanted individually to plastic bags of 7l capacity in April of the same year. In September, the seedlings were grafted with the selection virus-free of ‘Navelina INIASEL 7-5’.
M.A. Forner-Giner et al. / Scientia Horticulturae 98 (2003) 223–232
225
Table 1 Rootstocks tested for ‘Navelina’ orange Code no.a Botanical namesb
02034 020349 03015
C. sinensis (L.) Osb. P. trifoliata (L.) Raf. C. reshni Hort. ex Tan. C. volkameriana Ten. & Pasq. C. sinensis P. trifoliata (C. sinensis P. trifoliata) C. reshni (C. sinensis P. trifoliata) C. reshni C. reshni P. trifoliata
03017 030113
C. reshni C. reshni
030123 030142 030146 03027 030212
C. C. C. C. C.
a b
reshni reshni reshni reshni reshni
Common name/cultivar Carrizo citrange
Cleopatra mandarin Volkamer lemon C-35 citrange Troyer citrange Cleopatra mandarin no. 4 Troyer citrange Cleopatra mandarin no. 49 Cleopatra mandarin ‘Rubidoux’ trifoliata orange no. 5 (registered in EU as Forner Alcaide 5) P. trifoliata Cleopatra mandarin ‘Rubidoux’ trifoliata orange no. 7 P. trifoliata Cleopatra mandarin ‘Rubidoux’ trifoliata orange no. 13 (registered in EU as Forner Alcaide 13) P. trifoliata Cleopatra mandarin ‘Rubidoux’ trifoliata orange no. 23 P. trifoliata Cleopatra mandarin ‘Rubidoux’ trifoliata orange no. 42 P. trifoliata Cleopatra mandarin ‘Rubidoux’ trifoliata orange no. 46 (C. sinensis P. trifoliata) Cleopatra mandarin Troyer citrange no. 7 (C. sinensis P. trifoliata) Cleopatra mandarin Troyer citrange no. 12
Codes used in the rootstock breeding program. Botanical names according to Ortiz (1986).
The substrate used, steam sterilized, was composed by siliceous sand (40%), peat moss (60%), calcium superphosphate (1.5 kg/m3), dolomite (2.22 kg/m3), CaCO3 (3 kg/m3), CuSO4 (83.6 g/m3), ZnSO4 (27.8 g/m3), MnSO4 (27.8 g/m3), FeSO4 (46.4 g/m3), H3BO3 (728 mg/m3) and (NH4)6Mo7O244H2O (370 mg/m3). Plants were irrigated, once weekly, with a nutrient solution composed of monoammonium phosphate (0.15 g/l), Ca(NO3)2 (0.67 g/l), KNO3 (0.09 g/l), CuSO4 (0.008 mg/l), ZnSO4 (0.089 mg/l), MnSO4 (1.95 mg/l), H3BO3 (0.57 mg/l) and (NH4)6Mo7O244H2O (0.036 mg/l) and V2O5 (0.0065 mg/l). An iron chelate (6% Fe2þ) was added at 0.25 g/l each 4 weeks. The budded trees were planted on 29 October, 1990, in a plot at IVIA. There was one tree on each rootstock arranged in six randomized complete blocks. Tree spacing was 5:2 m 4:5 m. One guard row was also planted around the experimental plot. The soil was sandy-loam, with 24.6% of CaCO3, 5.4% de-active calcium carbonate and pH ¼ 7:5. The plot was originally planted with oranges on sour orange rootstock. One year before planting, old trees were uprooted and the plot was prepared by removing 50 cm of topsoil, leveling the subsoil and spreading the topsoil. Standard cultural practices were used, with mechanical weed control between rows and chemical control between trees. After 3 years of culture, trees were hand pruned annually in January. Drip irrigation was installed, adjusting the frequency, according to the season of the year, from 1 (in winter) to 5 days (in summer) per week, with 40 l/tree in each irrigation. Water pH was 7.60, electrical conductivity 1.40 mS/cm, Cl 134.8 mg/l and NO3 158.0 mg/l. Fertilization was applied from the 2nd year and increased annually. The amounts applied in 2000 were: ammonium nitrate (33%) 2 kg/tree, monoammonium phosphate 0.5 kg/tree, KNO3 0.8 kg/tree, epsonite 3.6 g/tree and iron chelate 18 g/tree.
226
M.A. Forner-Giner et al. / Scientia Horticulturae 98 (2003) 223–232
In November or December, the crop of each tree was harvested and weighed. Fruit quality was determined in the 5th (1998–1999) and 7th harvests (2000–2001). After harvest, 25 fruit samples per tree were taken. The samples were weighed, fruit diameter measured and cut in a half. Rind thickness was determined with a digital caliper and juice extracted with an electric squeezer. The juice and the flesh were collected in a mesh bag (40 filaments/cm) and juice extracted by hand squeezing the bag until no juice remained. The flesh left in the bag was about 8% of the total weight of the fruit. Solids (TSS) were determined by an Atago digital temperature-compensated refractometer, model PR-1. Acids (TA) were determined by titration with 0.1 N NaOH using a Brand digital burette, model II and a solution of 1% phenolphthalein in ethanol as indicator. In the 5th crop, peel color index was determined before cutting the fruits, with a Minolta colorimeter, model CR-300, taking three measurements per fruit at the equator level. Tree size was evaluated in January 2001 using the formula V ¼ 0:524hd 2 that is one-half of a prolate spheroid and where h is the tree height and d the average of two diameters N–S and E–W (Turrell, 1946). The data were tested using the MSTAT program for analysis of variance (ANOVA 2) and Duncan’s multiple range test at P ¼ 0:05 for the mean separation.
3. Results and discussion Trees grew normally throughout and none were affected by Phytophthora spp. or other known pathogens. Neither were iron chlorosis nor salinity symptoms observed. 3.1. Yield Trees on nine rootstocks out of the 14 tested, yielded their first fruits in 1994, 4 years after planting in the field (Table 2). C. volkameriana produced the highest crop and no fruits developed on trees of Cleopatra mandarin, Carrizo citrange and selections 02034, 03017 and 030142. During the 1995/1996 season, all trees produced fruits, but no significant differences were detected between rootstocks. In the following harvests, the yield increased until the 1999/2000 season, which may be considered the first season of full production. Trees on C. volkameriana rootstock produced the highest cumulative yield (Table 2), followed, with no significant differences, by trees on F&A 5, F&A 13 and 030123 rootstock selections. The cumulative yield of trees on Carrizo citrange and Cleopatra mandarin was lower than the average. In Spain, it is usual that scaffold branches are formed next to the bud union and, therefore, it is difficult to measure the trunk cross-sectional area. In these conditions, the canopy volume is a better parameter to evaluate tree size. The larger trees, measured as canopy volume (m3), were found on the 03017 rootstock selection, with no significant differences compared with trees on Volkamer lemon and the selections 030123 and 030146 (Table 2). The smallest trees were found on the 02034 rootstock selection without significant difference with trees on 03027, 020349 and F&A 13 hybrid rootstock selections. The highest yield efficiency was shown by trees on the 02034 rootstock selection, followed by F&A 13, with no significant differences (Table 2). The lower yield efficient
Table 2 Yield, tree size and yield efficiency of ‘Navelina’ orange on 14 rootstocks, planted in October 1990a Yield (kg/tree)a
Rootstocks
1994/1995 1995/1996 1996/1997 1997/1998 1998/1999 1999/2000 2000/2001
F&A 13 030123 03017 030146
020349 030212 030142 02034 03027 Mean CV (%) a
Volkamer lemon Cleopatra ‘Rubidoux’ trifoliata no. 5 Cleopatra ‘Rubidoux’ trifoliata no. 13 Cleopatra ‘Rubidoux’ trifoliata no. 23 Cleopatra ‘Rubidoux’ trifoliata no. 7 Cleopatra ‘Rubidoux’ trifoliata no. 46 C-35 citrange Troyer Cleopatra no. 49 Cleopatra mandarin Cleopatra Troyer no. 12 Cleopatra ‘Rubidoux’ trifoliata no. 42 Troyer Cleopatra no. 4 Carrizo citrange Cleopatra Troyer no. 7
Yield efficiency (kg/m3)
Tree height (m)
Canopy volume (m3)
282.32 a 259.85 ab
1.97 bc 1.88 cd
7.13 a–c 5.71 b–e
41.55 c–e 46.30 b–d
254.15 a–c
1.65 d–g
4.88 d–f
54.59 ab
1.50 a 0.24 b
1.87 a 2.30 a
13.84 ab 14.09 ab
31.02 bc 37.43 ab
66.08 a 58.31 ab
94.33 a 77.58 b
0.17 b
2.57 a
16.52 a
46.15 a
52.86 bc
70.44 b–d 65.45 a–d
0.09 b
1.93 a
13.27 ab
29.26 bc
54.19 a–c 67.83 b–e 71.68 ab
238.26 a–d
1.85 c–e
6.44 a–d
37.69 c–g
0.00 b
1.70 a
4.18 de
32.56 bc
51.97 bc
0.19 b
1.73 a
8.23 b–e 27.44 bc
0.70 0.42 0.00 0.16 0.00
0.16 2.67 1.16 2.33 1.33
b b b b b
0.00 b 0.00 b 0.10 b 0.25 263
a a a a a
3.13 a 1.47 a 2.43 a 1.91 115
12.27 11.72 4.50 8.23 3.31
a–c a–d c–e b–e e
30.32 28.66 27.92 26.42 31.01
bc bc bc bc bc
73.68 a 69.91 ab
Tree size
76.45 bc
67.85 a–c
234.71 b–d
2.22 ab
8.07 a
29.81 fg
45.82 b–e 75.45 bc
56.86 a–d
215.72 b–e
2.30 a
7.69 ab
29.47 fg
43.93 47.19 41.73 41.92 37.79
53.98 54.14 60.75 59.58 50.87
213.18 204.37 195.89 195.74 187.25
1.80 1.50 1.84 1.73 1.73
5.53 4.41 5.89 5.13 5.37
39.40 48.15 34.63 43.99 35.22
c–e b–d c–e c–e de
70.61 59.57 59.82 57.09 62.93
b–d d–f d–f d–f c–f
b–d b–d a–d a–d cd
c–f d–f d–f d–f ef
c–e fg c–e c–f c–f
c–e d–f b–e c–e c–e
c–f bc e–g b–e d–g
6.97 b–d 28.78 bc 2.17 e 24.78 bc 4.50 de 22.56 c
44.87 c–e 50.54 f 36.84 de 60.16 d–f 33.53 e 54.41 ef
47.82 d 51.24 cd 49.45 cd
182.11 ef 176.65 ef 166.99 f
1.40 g 1.93 cd 1.57 e–g
3.08 f 6.47 a–d 4.09 ef
59.11 a 27.35 g 42.39 c–e
8.84
30.31
46.93
66.94
59.52
214.80
1.81
5.71
40.69
35
21
17
23
16
12
27
21
67
M.A. Forner-Giner et al. / Scientia Horticulturae 98 (2003) 223–232
F&A 5
Cumulative yield (kg/tree)
Mean separation within columns by Duncan’s multiple range test at P 0:05.
227
228
M.A. Forner-Giner et al. / Scientia Horticulturae 98 (2003) 223–232
trees were those grafted on Carrizo citrange, 030146, 03017, Cleopatra mandarin and 030142 in ascending order and with no significant differences between them. Trees on 020349 and on F&A 5 selections had also a good yield efficiency. 3.2. Fruit quality As most fruits are destined for fresh consumption, fruit size, juice content and TSS/TA are of great importance in Spain. The Commission Regulation (EC) no. 1799/2001 of 12 September 2001, established as a marketing standard for ‘Navelina’ orange, a minimum juice content of 35% and a minimum fruit size, determined as the diameter of the equatorial section of 53 mm. Nevertheless, the best commercial diameters range between 73 and 96 mm with a weight between 200 and 300 g/fruit. The Spanish regulations for the season 2001–2002, establish that ‘Navelina’ orange and other early ripening varieties can be exported when the TSS/TA ratio reaches 6.5. There were differences between rootstocks and their effects on the external parameters of fruit quality (Table 3). Volkamer lemon produced the larger fruits in both harvests. In the 5th crop, trees on Volkamer lemon and C-35 citrange produced the heaviest fruits, but without significant difference with Carrizo citrange and the 02034, 020349, 030123, 030142 and 030212 hybrid selections. In the 7th crop, Volkamer lemon also produced the heaviest fruits although there were no significant differences with C-35 citrange and the 030123 and 030142 selections. The smallest fruits were from the 03027 selection in the 5th harvest. In the 7th crop, the 030146 selection produced the smallest fruits, without significant differences with the 03027 and F&A selections, and trees on F&A 13 developed fruits with the lowest weight, no differences were detected compared with most of the other rootstocks tested. Fruits from trees on C-35 citrange, C. volkameriana and the 02034 selection had the thickest rind in the 5th crop, whereas the trees on Cleopatra mandarin produced the thinnest, there were small differences between rootstocks. In the 7th crop, fruits from trees on Volkamer lemon had the thicker rind and the 030113 selection the thinnest, small differences were also found between rootstocks (Table 3). Minor differences were noticed between rootstocks, for both harvests, in most of the internal parameters determined and in the peel color (Table 4). Peel color index in fruits of trees on Cleopatra mandarin rootstock were significantly lower and no differences were shown in other rootstocks. Trees on the 020349 rootstock selection, in the 5th crop, and on Volkamer lemon in the 7th, had the lower juice content, but small differences between rootstocks were detected in both harvests. In both the crops, fruits of trees on Cleopatra mandarin showed the lowest TSS/TA ratio, although without significant differences with the 02034 and 030212 selections. For this reason, these rootstocks can be recommended only for cultivars for midseason o late harvest time. In the 5th crop, the higher TSS/TA ratio was determined for fruits on the 030142 rootstock selection, without significant differences with Carrizo and C-35 citranges, and the 030113 and 03027 selections. The results were similar in the 7th crop, but a higher ratio was found in the 03017 selection with no significant differences with Carrizo and C-35 citranges, Volkamer lemon and 020349, 030142 and 03027 selections (Table 4).
Rootstocks
02034 020349 F&A 5 03017 F&A 13 030123 030142 030146 03027 030212 Mean CV (%) a
Carrizo citrange Cleopatra mandarin Volkamer lemon C-35 citrange Troyer Cleopatra no. 4 Troyer Cleopatra no. 49 Cleopatra ‘Rubidoux’ trifoliata Cleopatra ‘Rubidoux’ trifoliata Cleopatra ‘Rubidoux’ trifoliata Cleopatra ‘Rubidoux’ trifoliata Cleopatra ‘Rubidoux’ trifoliata Cleopatra ‘Rubidoux’ trifoliata Cleopatra Troyer no. 7 Cleopatra Troyer no. 12
no. no. no. no. no. no.
5 7 13 23 42 46
5th crop (data: 23 November 1998)
7th crop (data: 11 December 2000)
Fruit weight (g)
Fruit diameter (mm)
Rind thickness (mm)
Fruit weight (g)
Fruit diameter (mm)
Rind thickness (mm)
229.53 212.72 242.77 242.96 223.62 223.53 214.55 203.56 209.84 226.25 224.03 206.49 199.48 231.87
77.0 75.3 79.0 78.3 76.1 75.9 75.1 73.8 73.8 76.5 76.3 74.0 73.3 77.4
4.52 4.14 4.79 4.87 4.69 4.28 4.46 4.19 4.21 4.51 4.34 4.35 4.47 4.28
228.81 208.90 272.96 240.84 229.97 236.78 234.25 231.20 201.64 258.77 252.75 231.55 207.58 232.07
77.2 75.9 82.2 78.6 76.9 78.7 77.9 77.9 74.2 80.5 79.9 64.7 75.0 78.2
5.78 5.26 5.97 5.56 5.28 5.36 5.38 5.40 5.04 5.63 5.06 5.39 5.14 5.06
a–c b–d a a a–d a–d b–d cd b–d a–d a–d b–d d ab
220.80
75.8
9
3
a–c b–d a ab a–d a–d b–d cd cd a–d a–d cd d ab
4.44 6
bc d ab a ab cd b–d cd cd bc cd cd b–d cd
233.44 11
b–d cd a a–c b–d b–d b–d b–d d ab ab b–d cd b–d
a a a a a a a a ab a a b ab a
77.0
5.38
11
8
ab b–d a a–d b–d b–d b–d b–c d a–c cd b–d cd cd
M.A. Forner-Giner et al. / Scientia Horticulturae 98 (2003) 223–232
Table 3 Fruit quality of ‘Navelina’ orange on 14 rootstocks: external parametersa
Mean separation within columns by Duncan’s multiple range test at P 0:05.
229
230
Rootstocks
02034 020349 F&A 5 03017 F&A 13 030123 030142 030146 03027 030212 Mean CV (%) a
Carrizo citrange Cleopatra mandarin Volkamer lemon C-35 citrange Troyer Cleopatra no. 4 Troyer Cleopatra no. 49 Cleopatra ‘Rubidoux’ trifoliata Cleopatra ‘Rubidoux’ trifoliata Cleopatra ‘Rubidoux’ trifoliata Cleopatra ‘Rubidoux’ trifoliata Cleopatra ‘Rubidoux’ trifoliata Cleopatra ‘Rubidoux’ trifoliata Cleopatra Troyer no. 7 Cleopatra Troyer no. 12
5th crop (data: 23 November 1998)
no. no. no. no. no. no.
5 7 13 23 42 46
7th crop (data: 11 December 2000)
Juice content (%)
Soluble solids (%)
TSS:TA
55.93 56.26 53.88 55.40 56.36 51.46 55.11 56.19 56.35 55.86 55.47 54.08 54.96 55.42
11.42 10.56 10.40 11.10 11.57 10.90 11.18 10.95 10.63 10.87 11.05 10.77 11.27 10.63
8.89 7.25 8.98 9.07 7.70 8.62 8.23 8.62 8.89 8.30 9.36 8.14 8.92 7.68
55.20 5
a a ab a a b a a a a a ab a a
ab cd d a–d a a–d a–c a–d cd a–d a–d b–d a–c cd
10.95 5
Mean separation within columns by Duncan’s multiple range test at P 0:05.
8.48 6
a–c f ab ab ef b–d de b–d a–c cd a de ac ef
Peel color index 7.96 3.68 7.37 6.90 7.01 8.12 8.35 7.50 6.53 7.75 8.02 7.08 7.94 6.47 7.19 21
a b a a a a a a a a a a a a
Juice content (%)
Soluble solids (%)
TSS:TA
52.14 53.73 51.21 53.12 54.81 51.16 53.30 52.05 52.05 53.67 53.56 51.94 52.29 52.43
13.25 12.08 12.55 13.02 12.83 12.78 12.82 12.57 12.73 12.58 12.83 12.93 12.93 12.32
10.81 8.47 11.17 11.76 9.53 11.15 10.50 12.05 10.62 10.63 11.81 10.42 11.51 9.57
52.74 3
bc ab c a–c a c a–c ab bc ab ab bc bc bc
12.73 5
a c a–c ab a–c a–c a–c a–c a–c a–c a–c ab ab bc
10.72 9
a–d e a–c a–c de a–c b–d a b–d b–d ab cd a–c de
M.A. Forner-Giner et al. / Scientia Horticulturae 98 (2003) 223–232
Table 4 Fruit quality of ‘Navelina’ orange on 14 rootstocks: internal parameters and peel colora
M.A. Forner-Giner et al. / Scientia Horticulturae 98 (2003) 223–232
231
Total soluble solids were higher on the 02034 rootstock and lower on Volkamer lemon rootstock, for the 5th crop and higher on Carrizo citrange and lower on Cleopatra mandarin for the 7th crop, without significant differences compared to most of the rootstocks tried (Table 4).
4. Conclusions F&A 5 and F&A 13 selections are hybrids of Cleopatra mandarin P: trifoliata. Both are resistant to citrus tristeza virus (CTV) (Forner and Alcaide, 1997; Forner et al., in press). Moreover, F&A 5 is resistant to the citrus nematode T. semipenetrans Cob. (Verdejo-Lucas et al., 1997, 2000), less susceptible to lime-induced chlorosis, than Carrizo citrange and has a good tolerance to salinity and flooding (Forner and Alcaide, 1997). The F&A 13 selection is susceptible to lime-induced chlorosis like Carrizo citrange, but has an excellent tolerance to salinity and flooding (Forner et al., in press). The results obtained in this test show that, in addition to the characteristics described, the selections F&A 5 and F&A 13 have an excellent yield efficiency and fruit quality. As a whole, both selections have better performance than the rootstocks used at present in Spain. F&A 5 is soon going to be used commercially in Spanish citrus nurseries. The 02034 selection is tolerant to CTV (unpublished data) and seems interesting because of its tree size, yield efficiency and fruit quality. It has also good tolerance to calcareous soils, although it is sensitive to citrus nematode (Verdejo-Lucas et al., 1997). The low TSS/ TA ratio obtained in this test, can be interesting for cultivars of mid or late picking season. The 03017, 030123 and 030142 produced low yield efficiency in this trial. Nevertheless, it may be interesting to include these rootstock selections in other tests because they are resistant to CTV (unpublished data) and the citrus nematode (Verdejo-Lucas et al., 1997, 2000) and have good tolerance to calcareous soils in the preselection trials. None of the other hybrid selections tested (020349, 030146, 03027 and 030212) can be considered as interesting for commercial use with ‘Navelina’ scions. C-35 citrange performed well in this test, but in other trials still in progress (unpublished data) showed more susceptibility to lime-induced chlorosis than Carrizo citrange.
Acknowledgements Thanks are given to Dr. E.A. Carbonell for his advice on the statistical analysis. This work was financed by the Instituto Nacional de Investigacio´ n y Tecnologı´a Agraria y Alimentaria (INIA), grants no. 8127, SC94-037-C2-1 and SC98-103-C2-1 and the Instituto Valenciano de Investigaciones Agrarias. References Cameron, J.W., Soost, R.K., 1986. C35 and C32: citrange rootstocks for citrus. HortScience 21 (1), 157–158. Forner, J.B., 1996. Perspectivas en la utilizacio´ n de patrones en citricultura. In: Ayuntamiento de Nules (Ed.), 1995. II Congreso de Citricultura de La Plana. 23–25 de marzo de 1995, Nules, Castello´ n, pp. 29–41.
232
M.A. Forner-Giner et al. / Scientia Horticulturae 98 (2003) 223–232
Forner, J.B., Alcaide, A., 1993. La mejora gene´ tica de patrones de agrios tolerantes a tristeza en Espan˜ a: 20 an˜ os de historia (I). Levante Agrı´cola 325, 261–267. Forner, J.B., Alcaide, A., 1994. La mejora gene´ tica de patrones de agrios tolerantes a tristeza en Espan˜ a: 20 an˜ os de historia (II). Levante Agrı´cola 329, 273–279. Forner, J.B., Alcaide, A., 1997. Nuevos patrones de agrios (I): Hı´brido ‘Forner–Alcaide no. 5’. Levante Agrı´cola 341, 301–303. Forner, J.B., Alcaide, A., Verdejo Lucas, S., Sorribas, F.J., 1997. New hybrids as citrus rootstocks in Spain. In: Manicom, B., Robinson, J., F du Plesis, S., Joubert, P., L van Zyl, J., du Preez, S. (Eds.), 1996 Proceedings of the International Society Citriculture, vol. I, May 12–17, 1996, Sun City, South Africa, pp. 167–170. Forner, J.B., Forner, M.A., Alcaide, A., Verdejo Lucas, S., Sorribas, F.J., 2003. New hybrid citrus rootstocks released in Spain. In: Proceedings of the IX International Congress, December 3–7, 2000. International Society of Citriculture, Orlando, FL, in press. Forner, J.B., Aparicio, M., Alcaide, A., Giner, J., Pina, J.A., Sala, J., 1982. Present status of citrus rootstocks in Spain. In: Matsumoto, K. (Ed.), 1996 Proceedings of the International Society Citriculture, vol. 1, November 9–12, 1981, Tokyo, Japan, pp. 106–109. Ministerio de Agricultura, Pesca y Alimentacio´ n (MAPA), 1990. Anuario de estadı´stica Agraria. Madrid. Newcomb, D.A., 1978. Selection of rootstocks for salinity and disease resistance. In: Grierson, N. (Ed.), 1977 Proceedings of the International Society Citriculture, vol. II, May 1–8, 1977, Orlando, FL, pp. 117–120. Ortiz, J.M., 1986. Nomenclatura bota´ nica de los cı´tricos. Fruits 41 (3), 199–209. Pina, J.A., Sevillano, J.J., Polo, A., 2000. Plantas de vivero de cı´tricos en la Comunidad Valenciana. Comunidad Valenciana Agraria 15, 23–27. Turrell, F.M., 1946. Tables of Surfaces and Volumes of Spheres and of Prolate and Oblate Spheroids and Spheroidal Coefficients. University of California Press, Berkeley. Verdejo-Lucas, S., Sorribas, F.J., Forner, J.B., Alcaide, A., 1997. Screening of hybrid citrus rootstocks for resistance to Tylenchulus semipenetrans Cobb. HortScience 32 (6), 1116–1119. Verdejo-Lucas, S., Sorribas, F.J., Forner, J.B., Alcaide, A., 2000. Resistance of hybrid citrus rootstocks to a Mediterranean biotype of Tylenchulus semipenetrans Cobb. HortScience 35, 269–273.