Morpho molecular characterization and hybridization studies in peach Prunus persica L Batsch

Abstract

The present investigation entitled Morpho-molecular characterization and hybridization newlinestudies in peach [Prunus persica (L.) Batsch] was performed at HRC, Patharchatta, G. B. Pant newlineUniversity of Agriculture and Technology Pantnagar and MBGE Laboratory of UCB, Haldi, newlinePantnagar, U.S. Nagar, Uttarakhand from January, 2021 to June, 2022. The whole study was newlinecompleted in 3 different experiments. In the 1st experiment the low chill peach cultivars (12 Nos) newlinemaintained at HRC, Patharchatta were estimated for their morphological and biochemical newlinecharacters. In the 2nd experiment the same peach cvs. as well as the high chill peach cvs. (29 Nos) newlinecollected from ICAR-NBPGR (RS), Bhowali, Nainital were characterized at molecular level. While, newlinein the 3rd experiment the hybridization studies among selected low chill peach cultivars were carried newlineout at HRC, Patharchatta and further hybridity was tested at MBGE Laboratory, UCB, Haldi. newlineThe results showed adequate amount of genetic variability among the different cultivars of newlinelow chill peaches. The fruiting characters namely; fruit length, diameter, weight and pulp: stone newlineratio varied from 39.14-66.30 mm, 32.82-62.63 mm, 30.24 to 123.70 g and 9.47-23.41, respectively. newlineThe ranges of total soluble solids (10.34-13.61 °Brix), titratable acidity (0.44-0.98%), ascorbic acid newline(9.58-14.58 mg/100g), total sugars (8.69-12.06%), anthocyanin (0.33-2.33 mg/100 g), total phenols newline(29.16-68.67 mg GAE/100g FW), flavonoids (6.79-61.90 mg/100 g) and antioxidant capacity newline(36.40-72.24%) was recorded among the various low chill peach cultivars. Among the various newlinecultivars tested, Shan-i-Punjab was found to be most productive (20.52 kg/tree), while Saharanpur newlinePrabhat estimated the highest yield efficiency (0.080 kg/cm2). newlineGenetic diversity among 41 genotypes of low and high chill peaches was examined with 25 newlineSSR primers, which indicated that beside two markers all showed polymorphism, resulted into 108 newlinepolymorphic bands. The highest polymorphic information content (PIC) was revealed by SSR newlinemarker BPPCT 033 (0.770) and lowest by MA020a (0.337). Jaccard s similarity coefficients varied newlinefrom 0.537 to 1.000 with an average value of 0.739. Among the 41 genotypes, the IC-360682 and newlineIC-360683; IC-360691 and IC-360680 and; Totapari and IC-247431 were found to be the most newlinesimilar with a similarity coefficients of 1.0, however, the minimum Jaccard s similarity coefficient newlinewas found between IC-209014 and Red June (0.537). newlineIn hybridization studies, crosses were made between selected low chill peach cultivars. The newlinemaximum fruit set (76.74%) was noted for hybrid H2 (Saharanpur Prabhat × Pratap) and minimum newline(55.93%) in H5 (Sharbati Surkha × Pratap). Maximum fruit retention was registered in hybrid H4 newline(Sharbati Late × Florida Red) i.e., 71.15%, whereas, hybrid H2 showed minimum fruit retention newline(39.85%). Among 25 markers employed for hybridity confirmation, only 3 primers set (CPPCT-022, newlineUDP96-005 and UDP98-407) were able to confirm the hybridity of the F1 seedlings. newlineThe cultivars identified to be promising in the investigation may prove to be potential newlinegenetic resource in low chill peach improvement programme. Further, SSR diversity may be used as newlinea criterion for selection of parents in the improvement of peach using hybrid breeding programme. newline