Dimri, D.C.Rajender Kumar2023-01-212023-01-212022-09https://krishikosh.egranth.ac.in/handle/1/5810192661The present investigation entitled “Morpho-molecular characterization and hybridization studies in peach [Prunus persica (L.) Batsch]” was performed at HRC, Patharchatta, G. B. Pant University of Agriculture & Technology Pantnagar and MBGE Laboratory of UCB, Haldi, Pantnagar, U.S. Nagar, Uttarakhand from January, 2021 to June, 2022. The whole study was completed in 3 different experiments. In the 1st experiment the low chill peach cultivars (12 Nos) maintained at HRC, Patharchatta were estimated for their morphological and biochemical characters. In the 2nd experiment the same peach cvs. as well as the high chill peach cvs. (29 Nos) collected from ICAR-NBPGR (RS), Bhowali, Nainital were characterized at molecular level. While, in the 3rd experiment the hybridization studies among selected low chill peach cultivars were carried out at HRC, Patharchatta and further hybridity was tested at MBGE Laboratory, UCB, Haldi. The results showed adequate amount of genetic variability among the different cultivars of low chill peaches. The fruiting characters namely; fruit length, diameter, weight and pulp: stone ratio varied from 39.14-66.30 mm, 32.82-62.63 mm, 30.24 to 123.70 g and 9.47-23.41, respectively. The ranges of total soluble solids (10.34-13.61 °Brix), titratable acidity (0.44-0.98%), ascorbic acid (9.58-14.58 mg/100g), total sugars (8.69-12.06%), anthocyanin (0.33-2.33 mg/100 g), total phenols (29.16-68.67 mg GAE/100g FW), flavonoids (6.79-61.90 mg/100 g) and antioxidant capacity (36.40-72.24%) was recorded among the various low chill peach cultivars. Among the various cultivars tested, Shan-i-Punjab was found to be most productive (20.52 kg/tree), while Saharanpur Prabhat estimated the highest yield efficiency (0.080 kg/cm2). Genetic diversity among 41 genotypes of low and high chill peaches was examined with 25 SSR primers, which indicated that beside two markers all showed polymorphism, resulted into 108 polymorphic bands. The highest polymorphic information content (PIC) was revealed by SSR marker BPPCT 033 (0.770) and lowest by MA020a (0.337). Jaccard’s similarity coefficients varied from 0.537 to 1.000 with an average value of 0.739. Among the 41 genotypes, the IC-360682 and IC-360683; IC-360691 and IC-360680 and; Totapari and IC-247431 were found to be the most similar with a similarity coefficients of 1.0, however, the minimum Jaccard’s similarity coefficient was found between IC-209014 and Red June (0.537). In hybridization studies, crosses were made between selected low chill peach cultivars. The maximum fruit set (76.74%) was noted for hybrid H2 (Saharanpur Prabhat × Pratap) and minimum (55.93%) in H5 (Sharbati Surkha × Pratap). Maximum fruit retention was registered in hybrid H4 (Sharbati Late × Florida Red) i.e., 71.15%, whereas, hybrid H2 showed minimum fruit retention (39.85%). Among 25 markers employed for hybridity confirmation, only 3 primers set (CPPCT-022, UDP96-005 and UDP98-407) were able to confirm the hybridity of the F1 seedlings. The cultivars identified to be promising in the investigation may prove to be potential genetic resource in low chill peach improvement programme. Further, SSR diversity may be used as a criterion for selection of parents in the improvement of peach using hybrid breeding programme.EnglishMorpho-molecular characterization and hybridization studies in peach [Prunus persica (L.) BatschThesis