Selection and Characterization of Known Genetic Marker Accessions for Hybridization with Commercial Varieties of Cucumis melo L.

Cucurbit Genetics Cooperative Report 19:49-52 (article 18) 1996

J. Jain, T.A. More
Division of Vegetable Crops, 1ARI, New Delhi-110012, India; Department of Horticulture, College of Agriculture, Kolhapur, Maharashtra, India

Introduction. The available cultivars of melon (Cucumis melo L.) require improvement in their resistance to diseases like powdery mildew, Fusarium wilt and CGMMV, in addition to other agronomic, vegetative, and fruit characters.

The improvement of available cultivars require broadening the genetic base by exploitation of existing genetic markers, for various characters such as disease resistance, in addition to other horticultural characters (1,3). This can be achieved by interspecific or intervarietal hybridization, which has number of limitations – the interspecific incompatibility being themost serious barrier (2). Somatic hybridization/protoplast fusion or normal selection followed by inbreeding can also be adopted to overcome this barrier. Thus, it becomes necessary to study the field performance of known genetic markers (1). In the present study, known genetic marker lines (1) obtained from Montfavet, France, have been characterized in order to incorporate the marker gene(s) in somatic hybridization and conventional hybridization studies based on their agronomic, vegetative, and fruit characters.

Materials and Methods. Melon is a summer crop and the ideal time for sowing in Delhi if February. The crop was sown in the third to fourth week of February. Preparation of the field was undertaken during the first two weeks of February, which requires proper manuring and irrigation of the field. Horizontal rows were made in the field and the seeds were directly sown on the edge of one side. Spacing of hills was kept as 1.0 m and row to row spacing was 2 m. Four to five seeds were sown per hill in an irrigated field.

The seven genetic marker lines (1) and the indigenous cvs were directly sown in the field in 1992, 1993 and 1994. The accessions resistant to powdery mildew, fusarium wilt and CGMMV (EC-327434, EC-37435, and EC-327440, respectively) were cored for vegetative characters. EC-327434 did not reach the fruiting stage because of Fusarium wilt infection during flowering. Various fruit characters listed in Table 1 and 2 were scored for accessions EC-237435, EC-237440, for Fusarium wilt-resistant lines Harela, Kakri, NC 62963, M4 and for ‘Pusa Madhuras’ (PM) and ‘Pusa Sharbati’ (PS).

Results and Discussion. Vegetative and fruit data for the accessions and cultivars are summarized in Tables 1 and 2.

Genetic marker line EC-327435 and EC-327440 can be utilized in conventional/somatic hybridization studies for incorporation of Pm-1, PM-2, and Fom-3 genes in cultivated/commercial varieties (1). these lines performed well under Delhi field conditions, producing fruit with good size, weight and seed number.

Table 1 Vegetative and fruit characters of melon accessions and cultivars under field conditions in Delhi, India.

Accession/cultivar

Vegetative characters

Fruit characters

Size and shape of the fruit
Color of the fruit skin
No. of ribs
Flesh color
‘Arka Jeet’ Yellowish green leaves with smooth leaf surface No flowering and fruit production
EC-327434

PI124112

(Pm-4, Pm-5)

Dark green leaves, leaf margin, inundated, somewhat rough leaf surface No flowering and fruit production
EC-327435 (‘PMR-5’)

(Pm-1, Pm-2)

Small, closely placed green leaves with smooth linear margin, hairy petiole Small size, round to oval shape Yellowish green, wrinkled skin 10 Orangish yellow
EC-327440 (‘Perlita FR’) (Fom-3) Large leaves with rough surface and hairy petiole Flat round to oblong in shape, medium sized fruits Greenish gray, rough rectum pattern of the skin 10 Pale green
Harela

(Fusarium wilt resistant)

Fast growing plant with small yellowing green leaves, smooth leaf surface, fragile Fruits not available
Kakri

(Fusarium wilt resistant)

Yellowish green leaves, smooth leaf surface with linear margin, hairy petiole Long,cylindrical, with tapering ends Ridged, light green Whitish green
M4 (developing line) Fusarium wilt resistant Small, closely placed yellowish green leaves with smooth leaf surface Round, large sized Greenish yellow, smooth skin 10 Greenish yellow
NC 62963

(Fusarium wilt resistant line)

Small, less spreading plant Long, oblong Yellowish to green with patchy skin Not present Whitish orange
‘Pusa Sharbati’ (PS) Small, fast growing plant Flat round, small sized Orange green with rough reticulate pattern of skin 10 Dark orange
‘Pusa Madhuras’ (PM) (Control) Fast growing vine, yellowish green small leaves with smooth serrated leaf margins, tendrils present Flat found Yellowish green, smooth skin with dark green ribs 10 Orangish yellow

Table 2. Fruit characters of some melon genetic marker lines and cultivars.

Accession/cultivar

Fruit weight

(g)

Flesh thickness

(cm)

Cavity

(cm)

Fresh seeds wt.

(g)

Soluble solids

(%)

EC-327435 350+95.39z 2.18+0.36 5.40+0.00 60.00+33.16 4.00+0.00
EC-327440 840.00+84.85 2.38+0.15 5.63+0.15 115.00+7.07 5.25+0.35
Kakri 700.00+24.47 NRy 6.38+0.95 NR NR
NC 62963 383.33+104.08 2.66+0.40 3.45+0.33 133.33+28.85 4.00+1.00
M4 1331.50+143.77 3.04+0.29 7.21+1.67 230.62+83.96 6.72+1.44
PS 575.00+35.35 3.50+0.70 5.25+0.35 56.00+7.07 6.50+0.70
PM 577.13+50.37 2.36+0.45 7.26+0.24 142.25+35.00 8.57+0.17

z mean + standard deviation.
y not recorded.

Literature Cited

  1. Jain, J. and T.A. More. 1994. Preliminary screening of indigenous cultivars and a few known marker lines of Cucumis melo for Fusarium wilt and CCMMV resistance. Cucurbit Gen. Coop. Report. 17:69-71.
  2. M. Chatterjee and T.A. More. 1991. Interspecific hybridization in Cucumis spp. Cucurbit Gen. Coop Report. 14:69-70.
  3. Nuez, F. J. Projens, M.J. Diez and P. Fernandez de Cordova. 1994. Cucumis melo L. accessions of the gene bank of the Polytechnical University of Valencia. Cucurbit Gen. Coop. Report. 17:57-60.