2. HORTICULTURAL SCIENCES
2.1.2 Cucurbitacious Crops .1 Cucumber
Identification of promising genotypes: Out of 32 selections evaluated, DC-39 and DC-43 showed consistently good performance with respect to fruit size, quality traits and yield (17.9 and 16.8 t/ha) showing an increase of 26.9 and 19.1%, respectively over national check Pant Khira-1 (14.1 t/ha).
Gynoecious hybrids DGCH-31 and DGCH-40 yielded 24.3 and 25.9 t/ha, respectively as compared to national check Pant Sankar Khira (19.8 t/ha). A new gynoecious hybrid DGCH-64 was entered IET of ACRP (VC).
Among the 12 gynoecious parthenocarpic pickling cucumber (gherkin) line sevaluated, DG-8 (Pusa Pickling Cucumber-8) was found most promising with an average fruit yield 84.9 t/ha (849 kg/ 100 m2) during winter season (November-March) under low cost polyhouse, which is 19.2% superior over Annaxo. A
natural variant, DC-48 with stay-green trait, extended shelf-life and other desirable horticultural traits was maintained and used in the breeding programme.
During kharif season 2019, 127 lines were screened for downy mildew resistance under natural and challenged inoculation conditions. Genotypes DC-77 (17.8 t/ha) and DC-70 (16.5 t/ha) showed highly resistant disease reaction against downy mildew besides having high yield, earliness and other desirable horticultural traits as compared to local resistant check Barsati (13.9 t/ha), Pharai Barsati (13.4 t/ha) and Panipat Local (14.7 t/ha). Out of 20 F1 hybrids evaluated DCH-16 (19.5 t/ha) and DCH-19 (1.8.9 t/ha) were found most promising with high yield and tolerant to downy mildew disease.
Identification of Cucumis sativus var. hardwickii with ToLCNDV resistance: Among C. sativus var. hardwickii genotypes, three genotypes (H-6, H-9 and H-16) were found to be highly resistant to this viral disease with score of less than 2.5 in scale of 0-10. The genotype, H-16 was used to develop F1 with three cultivated genotypes (Pusa Uday, Pusa Barkha and DC-43).
Identification of cucumber genotypes with resistance to downey mildew: One hundred and fifty four genotypes were evaluated for resistance to downey mildew caused by Pseudoperenospora cubensis both under natural field conditions and through artificial inoculation. The time of maximum disease appearance was September-November. Two genotypes, DC-70 and DC-77 showed good resistance under both conditions.
2.1.2.2. Bitter gourd
Indentification of promising hybrids: Twenty eight hybrids were evaluated for yield and related traits and the three best performing F1 hybrids for yield were S-2 × PA (DBGH-246; 30.33 t/ha), PDMGy-201 × PV (DBGH-163; 30.07 t/ha) and S-2 × PDM (28.19 t/ha).
Promising selections: Six promising genotypes, namely, DBGS 06-21, DBGS 60-52, DBGS 52-46, DBGS 54-58, DBGS 03-23 and DBGS-57-55 were evaluated under station trial. Among them, DBGS 06-21 gave the highest yield (24.53 t/ha) followed by DBGS 60-52 (21.24 t/ha) under open field conditions. The fruits of
DBGS 06-21 are dark green, 15-20 cm long, 4.5-5.5 cm diameter with pointed tubercles, discontinuous ridges, and individual fruit weight 85-90 g. Two promising selections (DBGS 32-1 and DBGS 57) were found promising under polyhouse conditions and recorded fruit yield of 4.10 and 3.85 q/100 Sq.m with individual mean fruit weight of 95 and 120 g, respectively.
Inheritance of fruit length: Inheritance of fruit length was investigated in the cross DBGS-2 × DBGS-34. The parents DBGS-2 and DBGS-54 had 26.64 & 12.60 cm long fruits, respectively; the parent DBGS-34 recorded fruit length of 5.75 cm, and hence, these crosses were found most suitable for genetic study of this trait. The mean fruit length in F2 (10.87 cm) was in between the short fruit parent and mid parent, and the distribution skewed toward the short fruit parent (DBGS-34) illustrating that short fruit length is partially dominant over long fruit types.
Variation of fruit length in F1 population of DBGS-2 x DBGS-54
2.1.2.3 Muskmelon
Identification of promising genotypes: The most promising genotype DM-154 was identified for open- field cultivation during station trial (28 genotypes). In summer 2019 it yielded of 23.2 t/ha having green flesh and 11.90Brix TSS followed by DM-156 (22.7 t/
ha, TSS 11.80Brix) and DM 193 (22.4 t/ha, TSS 11.60Brix) out of the 24 genotypes.
Promising selection for protected cultivation: The new selection of specialty melon (C. melo var. inodorous) DHM-39 has been developed, which was evaluated for
3 years in polyhouse/net house during summer (Feb- May) and off-season (Sep-Nov.) First fruit gets ready for harvest in about 85 days after sowing. Its fruit is oblong with average weight of about 1.5 kg. The rind colour of fruit is golden-yellow with no sutures. Its shelf-life is very high and fruits can be stored at room temperature for 15-20 days they are fruit is non-slipping at maturity. Fruit flesh is thick, light orange, juicy and very crispy with no typical musky flavour and high sweetness with 13.80Brix TSS. Its average yield is 5.5 tonnes / 1000 m2 under protected cultivation. Other promising lines are DHM-162 (5.3 t/1000 m2 with green flesh & TSS 13.60Brix) & DHM-159 (4.8 t/1000 m2) under protected cultivation.
Fruits of specialty melon genotype DHM-39
Promising hybrids of muskmelon: Two new hybrids from C. melo var. cantoupensis group DMH-18 (26.2 t/ha, TSS 11.90Brix) and DMH-23 (23.0 t/ha, TSS 11.40Brix) were found most promising in station trial (36 hybrids).
Two hybrids (DMH-5 and DMH-11) were promoted to AVT-II Hybrid Trial of AICRP (VC). Specialty melon hybrid DMH- 112 was found to be most promising with yield of 5.8 tonne/1000 m2 followed by DMH-119 (5.6 tonne/1000 m2) under nethouse during off-season cultivation from September to November.
Inheritance of flesh colour and climacteric fruit ripening: The population developed from Pusa Madhuras (C. melo var. cantaloupensis) and DHM-159 (C. melo var. inodorous) was used to study inheritance pattern of flesh colour and climacteric behavior of fruits. It was found that two genes are responsible for
flesh colour and 12:3:1 ratio was observed, while non- climacteric ripening of fruit was found to be controlled by single dominant gene.
Identification of source of resistance for ToLCNDV resistance: Eighty six genotypes from different horticultural groups of muskmelon were screened against ToLCNDV in field as well as net house during August to November. Two new sources of resistance (DSM-132 & DSM-19) were identified from Cucumis melo var. momordica germplasm. The most susceptible genotypes were DOM-118 (C. melo var. conomon) and Pusa Sarda (C. melo var. inodorous).
2.1.2.4 Bottlegourd
Genotype identification for hybrid seed production:
In order to develop morphological marker for hybrid testing to study the inheritance of segmented leaf shape in bottle gourd, genotype with normal leaf parents (Pusa Naveen) was crossed with genotype with segmented leaf parents (IC-5880840)(117). In F2, leaf character segregated in a ratio of 3 segmented: 1 normal leaf plants (χ2: 0.11; p value 0.64). When F1 was back crossed with Pusa Naveen, the progenies were segregated in 1:1 pattern (χ2: 0.45; p value 0.51), while in cross between F1 and IC-588084, all progenies were having segmented leaf type. The result has indicted the dominant behavior of gene for segmented leaf.
The character expressed even at first true leaf stage and hence can be used for identification of hybrid seed even at first true leaf stage.
Evaluation of hybrid and varieties: During kharif 2019, 31 F1 hybrids were evaluated out of which DBOGH-6 and DBOGH-12 were found promising with an average
yield of 4.9 and 4.8 t/ha, respectively. Out of 27 single plant selections, DBOGV-225 and DBOGV-170 were found promising with an average yield of 3.8 and 3.5 t/
ha, respectively as compared to Pusa Naveen (3.2 t/ha).
Detection of phytoplasma in fasciated stem of bottle gourd: Existence of phytoplasma infection was suspected in fasciated stem of bottle gourd and was characterized using nested PCR with universal P1 and P7 primers gave the expected product of ~1800 bp, followed by nested PCR with R16F2n and R16R2 primers which gave an expected product of ~1250 bp.
Nested PCR of phytoplasma DNA amplification from bottle gourd with primer pair R16R2n/R16F2n
Lane M: Marker 100 bp DNA ladder, lane 1: fasciated stem tissue, lane 2: Positive control,lane 3: Negative control
2.1.2.5 Pumpkin
Promising genotypes: Fifty genotypes were evaluated for yield and yield related traits, out of which six, namely, DPU-14, DPU-26, DPU-41, DPU-54, DPU-58 and DPU-165 were found promising. The plants of DPU-
DBOGH-6 DBOGH-12
Faciated stem in
IC-588084 Normat Stem
14 are medium viny with flattish-round fruits, medium ribs, orange flesh, average fruit weight 2.6 kg and with flesh thickness 2.7 cm. The fruits of DPU-41 and DPU- 165 are flattish-round having average fruit weight of 2.0 and 1.5 kg and flesh thickness of 2.5 and 2.1 cm, respectively. Genotype DPU-26 had cylindrical fruits having average weight of 3.5 kg and flesh thickness of 3.5 cm. The genotypes DPU-41, DPU-43 and Narendra Upkar showed the field tolerance against begomovirus (ToLCNDV) and potyvirus (PRSV).
Pumpkin hybrid DPU-41 x Narendra Amrit
In order to improve carotenoids content and flesh quality, selections were made in F2 segregating populations of pumpkin x butternut squash and butternut squash x pumpkin hybrids. Twenty five segregating generations (5 F4, 6 F5, 9 F6, 5 F7) were further advanced and promising individual plants were selected in each generation.
Promising hybrids: Thirty F1 hybrids were developed and evaluated for yield and related traits in the spring- summer season. The best performing F1 hybrids were DPU-41 x Narendra Amrit (av. fruit weight 3.78 kg, flesh thickness 3.4 cm), DPU-145 x Narendra Agrim (av.
fruit weight 2.35 kg, flesh thickness 3.4 cm), DPU-145 x DPU-63 (average fruit weight 2.38 kg, flesh thickness 3.12 cm) and DPU 41 x DPU 45 (av. fruit weight 2.3 kg, flesh thickness 2.8 cm).
2.1.2.6 Luffa (Sponge gourd)
Development of promising selections and F1 hybrids:
Genotype DSG-33 was advanced to AVT-I of AICRP (VC). Out of 42 F1 hybrids evaluated, DSGH-38 (17.1 t/ha) and DSGH-95 (16.8 t/ha) were found promising as compared to national check Kalyanpur Hari Chikni (12.3 t/ha). Another genotype DSGH-38 was entered in IET, while DSGH-95 was advanced to AVT-I of AICRP (VC) trial.
2.1.2.7 Ridge gourd
Out of 19 selections, DRG-7 having attractive green long fruit (35-40 cm) was found to be very promising showing an yield of 17.1 t/ha as compared to Pusa Nutan 16.3 t/ha was advanced to AVT-II of AICRP (VC) trial. Gynoecious F1 hybrid DRGH-4 (18.3 t/
ha) and DGRGH-8 (18.9 t/ha) were found promising and were advanced to AVT-II and AVT-I of AICRP (VC) trial, respectively. A new gynoecious based hybrid DRGGH-12 was entered in IET of AICRP (VC) trial. Twenty eight satputia (Luffa hermaphrodita (L.) Bhandari) lines were evaluated for yield and other traits. The line D-Sat-4 (Pusa Tripti) was found most promising having green superficial ribs, ready for first harvesting in 48-50 days and showed average fruit yield 15.5 t/ha, which was 35% superior over Kashi Khushi during spring summer season.
Fruits of Pusa Tripti