Salt Tolerance among Spanish Cultivars of Cucumis melo

Cucurbit Genetics Cooperative Report 10:41-42 (article 24) 1987

G. Anastasio, G. Palomares, and F. Nuez
Departamento de Biotecnología, Universidad Politécnica, 46020 Valencia, Spain

M. S. Catalá and J. Costa
CRIA La Alberca, 30150 Murcia, Spain

Coastal areas of the South East yield the main part of the vegetable crops grown in Spain but they are under the threat of soil salinization due to intensive irrigation with brackish waters and some parts are already unsuitable for some crops. A search for more tolerant crops is of great priority.

As we have at our disposal a wide germplasm collection of Spanish melons (1,2), the present work is focused on the selection of melon cultivars showing tolerance to high salinity conditions.

A pre-selection based on the soil, climate and problems of salinity of the origin areas of the cultivars was made.

Forty accessions of the local types: 5 ‘Rochet'(R), 12 ‘Piel de sapo'(PS), 10 ‘Amarillo'(A) and 13 ‘Tendral'(T) were chosen and planted in a highly salinized soil (ECe =35.0 dS/m; SAR=21.6) irrigated with brackish water (C3S1) (3) by via-flow system and at the same time in a control experiment. Both were carried out during the spring-summer of 1986 in Murcia in open air conditions sowing 14 small plots per accession with 2-3 seeds per plot.

The majority of the accessions initiated gemination in the salinity experiment although only 5 grew out of the seedling stage and set fruits (Table 1).

A strong reduction in the leaf surface was noted in every accession in comparison with the control, as well as a shortened internode length with reductions of about 80% and between 12 and 50% in the thickness of the shoot (Table 2).

The weight and size of the fruit were also strongly diminished in the experiment, the weight being more affected (between 58 and 84%) (Table 3).

The extreme conditions of salinity present in the experiment led to a lack of normal growth in the plants. Nevertheless, a number of accessions with some degree of tolerance useful for further breeding programs, especially that showed by 00073117, has been possible under natural conditions of high salinity.

Table 1. Survival data at several stages in the plant life cycle under saline conditions.

table 1

 

Table 2. Vegetative traits. Length (cm) between 1st and 4th internode (IL) and shoot diameters (cm) (SD) at 1st and 4th internode in both experiments.

table 2

 

Table 3. Characteristics of the fruit in both experiments.

table 3

Literature Cited

  1. Anastasio, G., J. Costa, J. Abadiá, M. L. Gómez-Guillamón, J. Cuartero, A. Alonso-Allende, A. Moreno, and F. Nuez. 1986. Evaluación de cultivares autóctonos de melón. Proc. II Congreso Nal. de la S.E.C.H. (in press).
  2. Nuez, F., J. Cuartero, J. Costa, and C. Ferrando. 1986. Recolección de especies hortícolas en España. Plant Genetic Resources Newsletter 66:28- 29.
  3. US Salinity Laboratory Staff. 1954. Diagnosis and improvement of saline alkali soils. US Dept. Agric. Handbook 60.

This work was supported by the research projects 2971/83-C3 and 0917/84-C2 sponsored by the CAICYT.