PNL Volume 18 1986 RESEARCH REPORTS

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THE EFFECT OF THE GENOTYPE ON IN VITRO ROOTING OF PEA SH00TS

Cardi, T. and E. Filippone C.N.R., Centro Studi Miglioramento

Genetico Ortaggi, Portici, Italy

In order to investigate the effect of the genotype on in vitro rooting

ability in peas an experiment was performed using nine genotypes showing

wide variability for growth behavior in vivo.

Shoots were obtained by culturing the buds of the cotyledonary node as

described earlier (3); the production of shoots was examined every week.

The number of transplantable shoots (i.e. 10-15 mm long) produced per bud

and the rate of production varied widely in the genotypes tested. P.

fulvum (JI 224) did not produce any transplantable shoots. Shoots were

induced to form roots on Murisighe Skoog half strength, sucrose 10g/l,

activated charcoal 2g/l, CaCl2 220 mg/1, agar 8g/l, pH 5.7-5.8 (3) in a

growth chamber at 24C and I6h light. The formation of roots, number of

roots formed per shoot, and shoot length were scored after five weeks.

A significant effect of the genotype (X =48.26 P<0.001) on the per-

centage of rooted shoots was found (Table 1). The rooting ability of pea

shoots seemed to decrease progressively in those regenerated from buds

cultured for a longer time, probably as a consequence of the residual effect

of IBA present at high concentration (5mg/l v. lmg/1 of IBA) in the medium

we used for bud culture. These results agree with those reported by other

authors (4,5). Moreover, it is noteworthy that in other experiments per-

formed in our laboratory the cuttings obtained in absence of any hormone

always rooted much more easily.

PNL Volume 18 1986 RESEARCH REPORTS

Table 1. In vitro rooting ability of different genotypes

1/ X² = 48.26 P<0.001

2/Both principal and lateral roots were considered

3/ Mean +/- S.D.

As concerns the number of roots per shoot, and their length, a very

high variability within genotype was found (Table 1) and it was still

present when a separate analysis within each week of bud culture was per-

formed for every genotype (Tables 2,3). As far as the number of roots

formed in each pea cutting is concerned, other authors also reported a

considerable variation (1,2). An effect of the duration of bud culture was

not found for either trait (Tables 2,3).

1. Eliasson, L. 1981. Physiol. Plant. 51:23-26.

2. Eliasson, L. and K. Areblad. 1984. Physiol. Plant. 61:293-297.

3. Filippone, E. 1985. PNL 17:12.

4. Hu, C. Y. and P. J. Wang. 1983. Handbook of Plant Cell Culture,

Vol. 1. (Evans, D. A., Sharp, W. R., Ammirato, P.V., and Yamada, Y.,

eds.). pp 177-227.

5. Kartha, K. K., 0. L. Camborg, and F. Constabel. 1974. Z.

Pflanzenphysiol. 72:1 72-1 76.

1/ Contribution no. 18 from Centro di Studio per il Miglioramento Genetico degli Ortaggi - C.N.R. - Portici (Napoli) - Italy

PNL Volume 18 1986 RESEARCH REPORTS

Table 2. Number of roots in rooted shoots (mean - S.D.).

-Only the weeks in which it was possible to analyze at least five shoots per

genotype are reported.

Table 3. Length of roots (in mm) in rooted shoots (Mean - S.D.).

1/ Only the weeks in which it was possible to analyze at least five shoots per

genotype are reported.



	PNL Volume 18 1986 RESEARCH REPORTS	7





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	1/ THE EFFECT OF THE GENOTYPE ON IN VITRO ROOTING OF PEA SH00TS

	Cardi, T. and E. Filippone C.N.R., Centro Studi Miglioramento Genetico Ortaggi, Portici, Italy In order to investigate the effect of the genotype on in vitro rooting ability in peas an experiment was performed using nine genotypes showing wide variability for growth behavior in vivo. Shoots were obtained by culturing the buds of the cotyledonary node as described earlier (3); the production of shoots was examined every week. The number of transplantable shoots (i.e. 10-15 mm long) produced per bud and the rate of production varied widely in the genotypes tested. P. fulvum (JI 224) did not produce any transplantable shoots. Shoots were induced to form roots on Murisighe Skoog half strength, sucrose 10g/l, activated charcoal 2g/l, CaCl2 220 mg/1, agar 8g/l, pH 5.7-5.8 (3) in a growth chamber at 24C and I6h light. The formation of roots, number of roots formed per shoot, and shoot length were scored after five weeks. A significant effect of the genotype (X =48.26 P<0.001) on the per- centage of rooted shoots was found (Table 1). The rooting ability of pea shoots seemed to decrease progressively in those regenerated from buds cultured for a longer time, probably as a consequence of the residual effect of IBA present at high concentration (5mg/l v. lmg/1 of IBA) in the medium we used for bud culture. These results agree with those reported by other authors (4,5). Moreover, it is noteworthy that in other experiments per- formed in our laboratory the cuttings obtained in absence of any hormone always rooted much more easily.



	8	PNL Volume 18 1986 RESEARCH REPORTS

	Table 1. In vitro rooting ability of different genotypes



	1/ X² = 48.26 P<0.001 2/Both principal and lateral roots were considered 3/ Mean +/- S.D. As concerns the number of roots per shoot, and their length, a very high variability within genotype was found (Table 1) and it was still present when a separate analysis within each week of bud culture was per- formed for every genotype (Tables 2,3). As far as the number of roots formed in each pea cutting is concerned, other authors also reported a considerable variation (1,2). An effect of the duration of bud culture was not found for either trait (Tables 2,3).

	1. Eliasson, L. 1981. Physiol. Plant. 51:23-26. 2. Eliasson, L. and K. Areblad. 1984. Physiol. Plant. 61:293-297. 3. Filippone, E. 1985. PNL 17:12. 4. Hu, C. Y. and P. J. Wang. 1983. Handbook of Plant Cell Culture, Vol. 1. (Evans, D. A., Sharp, W. R., Ammirato, P.V., and Yamada, Y., eds.). pp 177-227. 5. Kartha, K. K., 0. L. Camborg, and F. Constabel. 1974. Z. Pflanzenphysiol. 72:1 72-1 76. 1/ Contribution no. 18 from Centro di Studio per il Miglioramento Genetico degli Ortaggi - C.N.R. - Portici (Napoli) - Italy