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ThesisItem Open Access Grafting in parthenocarpic cucumber (Cucumis sativus L.) for yield and quality(Department of Horticultural (Veg. Science), BAU, Sabour, 2020) Anand, Kunal; Bhardwaj, AjayThe cucumber productivity of India/Bihar is almost half compared with the world’s productivity. Vegetable grafting is one such technique which can cater the needs of increasing productivity up to some levels. Grafting technique combines the vigorous root system of a plant with otherwise susceptible stem portion of another plant which has economic interest. The root system is called the rootstock, and the upper part which has economic interest is called scion. To explore the full potential in terms of productivity in parthenocarpic cucumber, the study on ҅Grafting in parthenocarpic cucumber (Cucumis sativus L.) for yield and quality’ was conducted at polyhouse complex of Department of Horticulture (Vegetable and Floriculture), BAU, Sabour, District-Bhagalpur, Bihar in the year 2019-2020 with the following objectives: 1) to identify suitable rootstock for yield and quality of parthenocarpic cucumber and 2) comparative study of grafted and non grafted parthenocarpic cucumber plants. The study included nine rootstocks viz., three from pumpkin, two of bottle gourd, two from sponge gourd, one from summer squash and one from monoecious cucumber grafted with parthenocarpic cucumber genotype adopting one cotyledon grafting method. The experiment was laid out in randomized block design with three replications and ten treatment combinations in the naturally ventilated polyhouse. The data for 22 traits was recorded viz., graft survival rate (%), number of leaves per plant (20, 40, 60 days after transplanting and at final harvest), node number to first female flower, days to first female flower, days to first harvest, number of fruits per vine, fruit yield (Kg/vine), fruit weight (g), fruit length (cm), fruit girth (cm), root length (cm), root fresh weight (g), root dry weight (g), vine length (cm), total soluble solids (˚brix), ascorbic acid content (mg/100g FW), chlorophyll ‘a’ content (mg/g FW), chlorophyll ‘b’ content (mg/g FW) and total chlorophyll content (mg/g FW). The data for 22 characters were subjected to analysis of variance and mean sum of squares due to genotypes was found significant for all the characters under study except for days to first harvest. The maximum graft survival percentage (21 days after grafting) was recorded in the combination of parthenocarpic cucumber (BRPCU-1) grafted on pumpkin (Chakor) rootstock and least in sponge gourd (Rajendra Nenua-1). The graft combination of parthenocarpic cucumber (BRPCU-1) grafted onto sponge gourd (Patna Local) rootstock produced significantly earlier first female flowers at lower nodes followed by sponge gourd (Rajendra Nenua 1) rootstock then non-grafted control. The rootstock of monoecious cucumber (Swarna Sheetal) with average fruit weight of 120.48 g, fruit yield of 3.19 Kg per vine and fruit length of 19.27 cm, was significantly superior then non grafted control. None of the grafted treatments surpassed non grafted check (BRPCU-1) for root dry weight, root length and vine length. The grafting combination of parthenocarpic cucumber scion (BRPCU-1) with rootstock of bottle gourd (Rajendra Chamatkar) recorded significantly superior total soluble solids whereas the pumpkin rootstock (Chakor) recorded significantly superior ascorbic acid content than non grafted parthenocarpic cucumber control. All the grafting combinations for total chlorophyll content revealed significant superior value than non grafted parthenocarpic cucumber control except the rootstock of sponge gourd (Rajendra Nenua-1) which was at par with the control. It can be concluded that the graft combination of monoecious cucumber (Swarna Sheetal) as rootstock and parthenocarpic cucumber as scion was the best for yield, and the rootstock bottle gourd (Rajendra Chamatkar) for quality purpose. From the study it was found that genotypic variability in selection of rootstock shows significant different results. Hence, to avail maximum benefits, the specific rootstocks can be identified before adopting the grafting technique at commercial level.ThesisItem Open Access Inheritance of gynoecy, parthenocarpy and yield in cucumber (Cucumis sativus L.)(Department of Horticulture (Veg. Science), BAU, Sabour, 2023) Sinha, Anuradha; Verma, R. B.Cucumber (Cucumis sativus L.) is cross-pollinated and generally monoecious in nature but gynoecious lines are also present which can be utilized efficiently for commercial F1 hybrid production. Monoecious cultivars require pollen for fruit sets which are not suitable for protected cultivation however fruits of these cultivars are highly demanded by consumers because of their crispiness and tender fruits. In the contrary, gynoecious cultivars with parthenocarpic traits do not require pollen for fertilization and thus fruit development and help in off-season production under protected conditions. Gynoecious and parthenocarpic cultivars have been used in production, but their genetic mechanism in cucumber is not well understood with conflicting reports. Also, the stability of gynoecious with parthenocarpic traits is highly influenced by environmental factors. Therefore, the present investigation was carried out at the department of horticulture (Veg. & Flori.), BAC, BAU, Sabour to study the inheritance of gynoecy, parthenocarpy and yield in cucumber during August- December 2022 inside a naturally ventilated polyhouse in randomized block design with three replications. Data were recorded from 30 plants of parent P1, parent P2 and their F1, 120 plants of F2 and 60 plants each of BC1P1 and BC1P2 from three crosses namely BRGCU-4 × BRCU-1-13, BRPCU-8 × BRCU-1-13 and BRPCU-8 × BRGCU-4 for morphological and quality parameters. Generation mean analysis exhibited additive, dominance and epistasis gene effect was important in determining the inheritance of characters under study. Sex ratio was under the control of additive gene effect and non additive gene effect whereas for trait parthenocarpy per cent and yield per plant was under the control of non-additive gene effect. Additive gene effect indicated the significance of a fixable type of gene hence selection could be beneficial in early generations for these characters however dominance gene effect indicated the predominance of non fixable type of gene thus, to enhance the performance of the trait postpones the selection to later generations by reduction of heterozygosity. The existence of epistasis may be due to the participation of different alleles in the heterozygous state. Thus, population improvement by recurrent selection may be beneficial for the enhancement of these traits in a particular cross. Inbreeding depression was non-significant for number of nodes to first female flower, days to anthesis of first female flower, sex ratio, days to first fruit harvest, number of fruits per vine, fruit weight, fruit length, fruit diameter, vine length, yield per plant and firmness in all the crosses which reflects the low reduction in the mean of F2 generation due to direct effect of homozygosity. Based on potence ratio, over dominance was noted for fruit diameter which can be exploited for getting transgressive segregants. The result of χ2 analysis of field and molecular data suggested that the gynoecy in BRGCU-4 and BRPCU-8 were controlled by a single complete dominant gene which can be transferred to horticulturally desirable varieties through backcross breeding and parthenocarpy in BRPCU-8 was under the control of single incomplete dominant gene. SSR11610, UW084119, SSR11343 and SSR13251 markers were used for the screening of gynoecious lines whereas SSR21886, SSR11858, SSR13251, SSR07248, SSR19165 and SSR01148 markers used for the screening of parthenocarpic gynoecious lines from monoecious lines and SSR21886 and SSR07248 markers used for the screening of parthenocarpic gynoecious lines from gynoecious lines. Therefore, these SSR markers are of great significance to ascertain the purity of the gynoecious and parthenocarpic line at an early stage of development.ThesisItem Open Access Effect of Plant Growth Regulators and Fruit Pickings on Growth, Yield and Seed Quality of Okra (Abelmoschus esculentus L. Moench)(Department of Horticulture (Vegetable), BAU, Sabour, 2022) Kumari, Ritu; Shree, SangeetaOkra (Abelmoschus esculentus L. Moench) is an annual, often cross-pollinated vegetable crop belonging to the family Malvaceae. It is an economically important vegetable crop grown in tropical and sub-tropical parts of the world. Okra has a prominent position among vegetables due to its wide adaptability, year round cultivation, export potential and high nutritive as well as medicinal value. It is good source of vitamin A, B and also contains vitamin C. It is rich in protein, iodine, calcium, potassium and other mineral matters. Okra has a vast potential as one of the foreign exchange earner crop. Among the green vegetables exported, okra accounts for about 60 per cent. Prolonged flowering and maturity of fruit in okra necessitates the picking of fruits at different stages. The seed quality is changed in fruits harvested at different picking due to differential supply of nutrient by mother plant. Plant growth regulators, considered as a new generation of agrochemicals when added in small amounts can bring the changes in the phenotypes of plants and affect growth either by enhancing or by stimulating the natural growth regulatory systems from seed germination to senescence. Plant growth regulators (PGRs) affect various aspects of plant physiology, mainly vegetative and reproductive traits including yield and seed production. Gibberellic acid (GA3) is a naturally occurring growth hormone which controls the extremely important aspects of plant growth through regulation of several growth processes such as seed germination, stem elongation, uniform flowering, and increased number of flowers. Considering the facts an experiment was conducted during 2018-19 and 2019-20 in Kharif season at Vegetable Research Farm, Bihar Agricultural University, Sabour, Bhagalpur, Bihar, India. Sixty (60) treatments consisting of 10 PGR levels, P0 (distilled water), GA3 (100 ppm, 150 ppm and 200 ppm), NAA (100 ppm, 150 ppm and 200 ppm), IAA (30 ppm, 60 ppm and 90 ppm), 2 Stage of plant for spraying of PGRs , S1 (4 leaf stage), S2 (4 leaf stage + Flower initiation) and 3 pickings of fruits, H1 (3 Pickings of fresh fruits + rest fruits left for seed production), H2 (6 Pickings of fresh fruits + rest fruits left for seed production), H3 (No pickings of fresh fruits + all fruits left for seed production) were laid out in randomized block design (factorial) with three replications to find out the most suitable PGR levels and stage of plant for spray as well as fresh fruit pickings to increase the seed yield of okra. Observations were recorded for growth, yield contributing parameters, seed quality parameters and storability of seed at 3, 6, 9, 12 months. The results obtained indicated significant three way interaction effects for all the parameters. It was observed that the different levels of treatments affected the growth and yield attributes of the crops. Among the treatments, the application of plant growth regulators P2 (GA3-150 ppm) along with three pickings of fresh fruits + rest of fruits for seed production (H1) in stage S1 (4 leaf stage) i.e. P2S1H1 treatment recorded maximum plant height (119.50 cm), number of fruits/ plant (15.25), fruit length (19.13 cm), number of seed/ pod (54.75), dry weight of fruit (5.59g), 100 seed weight (6.60), seed yield/ plant (32.64g), seed yield/ ha (12.37 q), germination % (86.36), seedling length (31.04 cm), vigour index-I (2787.73), vigour index-II (5.27) and seed viability (88.00). As far as study on seed storage is concerned the maximum germination % (88.18, 86.00, 83.00, 82.00), vigour index-1 (2974.00, 2758.00, 2872.00, 2782.00), vigour index-2 (5.45, 5.42, 5.35, 5.24) was recorded at three, six, nine, twelve months, respectively. Whereas, the minimum electrical conductivity (285.35, 286.60, 289.20, 291.85) was recorded at three, six, nine, twelve months, respectively. Similar trend was also observed under the application of plant growth regulators P1 (GA3-100 ppm) along with three picking of fresh fruits + rest of fruits for seed production (H1) in stage S1 (4 leaf stage) i.e. P1H1S1. On the basis of economics, the application of plant growth regulators P2 (GA3-150 ppm) along with three pickings of fresh fruits + rest of fruits for seed production (H1) in stage S1 (4 leaf stage) i.e. P2H1S1 was superior among all treatments, which gave the highest B: C ratio (5.54).ThesisItem Open Access Development of parthenocarpic hybrid(s) in cucumber and their micropropagation(Department of Horticulture (Vegetable Science), BAU, Sabour, 2021) Tripathi, Vishal; Singh, Vijay KumarThe present investigation in 28 F1 crosses along with eight parents developed through half diallel mating design and one check (RS-03602833) was carried out in randomized block design (RBD) with three replications in the saw toothed naturally ventilated polyhouse (500 m2) oriented in East-West direction at polyhouse complex of the department and lab experiments were conducted at tissue culture laboratory and post-harvest laboratory of the college. All the treatments exhibited significant variation as observed through ANOVA for RBD. For mean performance, hybrid BRPCU-2 × BRPCU-7 showed earliness in days to first female flower anthesis, node number to first female flower and days to first fruit harvest. While, hybrid BRPCU-1 × BRPCU-6, BRPCU-2 × BRPCU-7, BRPCU-1 × BRPCU-8 were the high yielders. Among inbreds, BRPCU-1 was earliest and genotypes BRPCU-3 exhibited highest fruit yield. In combining ability, crosses BRPCU-3 × BRGCU-4 and BRPCU-1 × BRPCU-6 were the good specific combiners for days to first fruit harvest. With respect to yield performance, the highest SCA effect manifested by the hybrid BRPCU-1 × BRPCU-6 for the characters namely yield per plant (g), fruits per plant, crop duration, fruit length (cm) and fruit diameter (cm) and DFFH, followed by BRPCU-2 × BRPCU-7 which exhibited significant desirable SCA effects for earliness (DFFFA, NFFF) as well as yield and its related traits namely fruits per plant and vine length (cm). The genotype BRPCU-3 was good general combiner in respect of earliness, yield and most of yield attributing traits. However, BRPCU-2 was good general combiner for earliness, yield and resistance to downy mildew traits. The significant heterotic hybrid in pooled over seasons for yield was BRPCU-1 × BRPCU-6, while the crosses BRPCU-6 × BRPCU-8 and BRPCU-5 × BRPCU-8 showed significant heterobeltiosis for number of fruits and yield (g) obtained per plant in pooled over seasons. Among all media treatments for micropropagation, Full strength MS supplemented with 2.5 mg/L BAP + 1.0 mg/ L IAA and Full strength MS supplemented with 2.5 mg/L BAP + 1.5 mg/ L IAA were the best treatments for shoot proliferation. While, Half MS supplemented with 0.5 mg/L NAA was best combination for rooting for all the four genotypes of cucumber. The potting mixture containing vermicompost-coco-peat in the ratio 1:1 was best for survival of regenerants. In postharvest study, hybrid BRGCU-4 × BRPCU-6 followed by BRGCU-4 × BRPCU-5 had good storability in respect to moisture loss and firmness of fruits.ThesisItem Open Access Morphological and molecular diversity analysis in bitter gourd (Momordica charantia L.)(Department of Horticultural (Olericulture), BAU, Sabour, 2021-02) Kumar, Sapan; Bhardwaj, AjayIndia is endowed with large amount of genetic diversity of bitter gourd based on morphological characters such as growth habit, maturity and various fruit characters including shape, size, colour and surface texture. However, the yield potential of bitter gourd in India and in Bihar is very low. In Bihar, bitter gourd has an area of about 10,090 hectares having production and productivity of 67,300 MT and 6.7 mT/ha respectively. In India, it is grown in an area of about 96,000 ha having production and productivity of 10,83,000 mT and 11.28 mT/ha respectively. Bitter gourd not exploited to its fullest and still confined to limited areas that too growing with local cultivars only is reason for low production. Being a highly nutritious crop, the breeding work is not up to the mark due to the presence of less genetic divergence between the genotypes. Hence, systematic evaluation of genetically divergent parent is needed for identifying divergent types. Keeping the points in view, the present investigation entitled “Morphological and molecular diversity analysis in bitter gourd (Momordica Charantia L.)” was carried out. The experiment was conducted at the Bihar Agricultural University in the Department of Horticulture (Vegetable and Floriculture) Sabour in the year 2019-2020 to study genetic diversity which involved evaluation of 20 bitter gourd genotypes including one check viz. Kahalgoan Local using morphological and molecular marker systems. The experiment was conducted in Randomized Block Design with two replications at vegetable research farm of the Bihar Agricultural University, Sabour, Bhagalpur during 2019-20. The present investigation was based on 18 quantitative characters. Significant differences were observed for all the eighteen characters in nineteen bitter gourd genotypes and present investigation documented that significant variability was present amidst the genotypes used. Based on mean performance it was observed that BRBT-1 (3.21 Kg) followed by US 6214 (3.08 Kg), US 1315 (3.02 Kg) and Pusa Aushadhi (2.41 Kg) were found significantly superior from check Kahalgoan Local for the character fruit yield per vine. Multivariate analysis showed that considerable genetic diversity was present in nineteen genotypes of bitter gourd studied and were arranged into six clusters. Cluster I was found to be having maximum number of eight genotypes in it. Cluster III, IV, V and VI were monogenotypic. Ascorbic acid (75.44 %) contributed maximum towards genetic divergence followed by total soluble solids (18.13 %), number of fruits per vine (2.92 %), fruit yield per vine (2.92 %) and internodal length (0.58 %). The highest inter cluster genetic divergence was noticed between clusters V and VI (267906.60) and was followed by clusters II and V (138645.60) and clusters III and V (108837.10). The intra cluster distance range varied from 8235.36 to 9804.83 with highest in cluster II (9804.33) succeeded by cluster I (8235.36). For molecular analysis among the 40 primers screened, only 6 primers showed polymorphism. Morphological diversity based on 18 quantitative traits and molecular diversity based on 6 polymorphic primers were not similar and the grouping pattern was different in the two systems, which indicated the role of environment in the expression of phenotypic traits and the preponderance of non-coding region in total genomic constitution. It can be concluded that, as a wide range of variation for almost all the economically important traits was present in this crop, so there is a vast scope for improvement through different breeding procedure. Based on the clustering pattern adopted through different procedure the diverse genotypes can be utilized for hybridization programme.ThesisItem Open Access Breeding for gynoecious hybrid development in cucumber (Cucumis sativus L.)(Department of Horticulture (Olericulture), BAU, Sabour, 2021-07) Kumari, Amrita; Kumar, RandhirThe present investigation entitled “Breeding for gynoecious hybrid development in cucumber (Cucumis sativus L.)” was carried out during 2018-2019 in two seasons (Zaid - Season I & Kharif - Season II). Field experiments were performed at the Vegetable Research Farm, Bihar Agricultural College, BAU, Sabour, whereas lab experiments were laid out in the Department of FS & PHT, BAU, Sabour. Five genetically diverse parental lines namely BRGCU-4, BRPCU-8, BRGCU-10, BRCU-1 and Punjab Naveen were crossed to develop 20 F1 hybrids following diallel mating design (including reciprocals). These hybrids along with parents and check hybrids (Don and Malini) were assessed in an experiment following RBD with three replications for 13 quantitative traits. All the recommended agronomic practices were followed to raise a healthy and successful crop. The gynoecious lines were maintained by spraying silver thiosulphate @ 300 ppm at 2 - 4 leaf stage. In each replication per treatment five plants were randomly selected for observations on plant, fruit and yield characters on individual plant basis. Analysis of variance revealed significant difference among the genotypes for the traits under study. The identification of suitable parental lines and F1 crosses is important for the genetic improvement of crops. In view of these facts, the diallel set of five parents and their consequent ten direct crosses and ten reciprocals were subjected to assess combining ability by following Griffings’ (1956)-method I and model I approach. BRCU-1, BRGCU-10 and BRPCU-8 emerged as good general combiners for most of the economic traits, based on an overall assessment of GCA effects and per se performance. Today the concept of heterosis is fundamental towards increased crop production. Maximum positive standard heterosis over both check Don (43.70 %) and Malini (40.05 %) were shown by the hybrids (BRGCU-10 × BRCU-1) followed by the hybrids BRCU-1 × BRGCU-10 and BRCU-1 × BRPCU-8. The investigation on post-harvest studies of gynoecious hybrids discusses various factors that can significantly affect the maintenance of quality in fresh cucumber during storage. In season I and season II, among the hybrids lowest physiological loss in weight was registered in gynoecious hybrid BRGCU-10 × BRGCU-4 (4.61 % and 4.83 %, in season I and II respectively) at the end of storage period. Highest values of firmness were observed in the hybrid BRGCU-10 × BRGCU-4 and BRGCU-4 ×BRCU-1 in season I and season II, respectively. Hybrid BRPCU-8 × Punjab Naveen in season I and BRGCU-10 × BRPCU-8 exhibited highest value of TSS in season II. From the foregoing findings it can be concluded that the heterosis estimates helps in selecting the best cross combinations for various yield and quality traits. Hybrid (BRGCU-10 × BRCU-1) followed by the hybrids BRCU-1 × BRGCU-10 and BRCU-1 × BRPCU-8 were the best being highly heterotic and having significant SCA effects in respect of yield and component traits. Overall, the findings of this study would be beneficial for farmers’ income enhancement since developed gynoecious based hybrid will reduce the cost of hybrid seed production drastically as compared to monoecious hybrids.ThesisItem Open Access Comparative analysis of genetic diversity in Bottle gourd [Lagenaria siceraria (Mol.) Standl.] using RAPD and ISSR markers for developing crop improvement strategies(Department of Horticulture (Olericulture), BAU, Sabour, 2019-05) Kumar, Rajesh; Kumar, RandhirAmong the all cultivated cucurbitaceous vegetables, bottle gourd (Lagenaria siceraria (Mol.) Standl.) with chromosome no. 2n = 22, is an annual monoecious crop synonymously called as calabash gourd. For the above investigation twenty-four genotypes collected from various states adjoining Bihar including breeding lines developed, collected and maintained at department. The genotypes of bottle gourd laid out in statistical design named Randomized Block Design with 3 replications in spring summer season of 2014 and 2015, respectively to examine the magnitude of variability and genetic diversity for several traits horticultural importance. In morphological study genotypes performed significantly in all traits studied, however BRBG-65 (591.10 q/ha) was proved to be high yielder with supporting traits like yield of marketable fruits/plant (15.19 kg) and no. of fruits/vine (14.85) in pooled analysis of both season than compare to the all three check varieties used in past study. Traits like fruit length, fruit circumference, no. of fruits per vine, yield of marketable fruits/vine, no. of seeds/fruit and fruit yield/hectare exhibited high GCV and PCV. Almost all the traits under study shown high percentage of heritability with maximum genetic advancement percentage for the traits like fruit length, fruit circumference, average fruit weight, no. of fruits/vine, yield of marketable fruits/vine, no. of seeds/fruit and yield per hectare. Traits like average fruit weight, no. of fruits plant and yield of marketable fruits/vine shown strong character association with fruit yield/hectare. Based on D2 values, twenty-four genotypes were classified amongst five clusters which indicated a large genetic diversity. Cluster II produced maximum no. (11) of genotypes followed closely by cluster I (8), whereas cluster V was proved to be mono-genotypic. Fruit length has given maximum contribution for total divergence. In the molecular study, average polymorphism percentage was obtained by RAPD pattern was studied by using 10 random primers. Total 58 reproducible amplicons were generated by 10 RAPD primers, of an average around 5.8 amplicon per primer. The value corresponding average polymorphic information content was 0.58 and ranged from 0.43 to 0.81. The major allele frequency was ranged from 0.33 to 0.73 with the average of 0.57. The major genetic diversity was ranged from 0.30 to 0.59 with the average of 0.41. ISSR pattern was studied by using 7 primers. Total 48 reproducible amplicons were generated by 7 ISSR primers of an average around 6.85 amplicon per primer. The value of average polymorphic information content was 0.56 and ranged from 0.29 to 0.76. The major allele frequency was ranged from 0.39 to 0.80 with the average of 0.59. The major gene diversity was ranged from 0.20 to 0.71 with the average of 0.44. Wide range of value regarding Jaccard’s similarity coefficient in RAPD markers (0.46 to 0.86), ISSR markers (0.37 to 0.910) and in combination (0.50 to 0.80). The dendrogram concluded relative magnitude of resemblance also amongst different clusters formed. Dendrogram and similarity matrix produced from both the markers RAPD and ISSR data then compared and concluded similar but not genetically identical phylo-genetic relationships, when RAPD, ISSR, and RAPD combination with ISSR derived dendrograms were compared, the discrimination among genotypes within these clusters was more effective with the combined analysis. Most genotypes studied in the present experiment differed with their geographic origin. The promising lines collected from different source were classified amongst different clusters and sub clusters. The genotype BRBG 65 was extremely diverse from other genotypes and the genotype BRBG 11-1 was genetically similar to BRBG 52 and BRBG 12-3. The investigation highlights the potential utilization of these germplasm for future breeding programmes.The genotypes of more divergent cluster may be utilized in breeding programme for developing high yielding varieties and F1 hybrids with desirable quantitative traits. The most promising genotype BRBG 65 may be recommended for commercial cultivation.ThesisItem Open Access Genetic Divergence in Pointed Gourd for Antioxidant, Nutritional and Postharvest Quality(Department of Horticulture ( Veg. & Flor.), BAU, Sabour, 2019-05) Ahmad, Mukhtar; Verma, R.B.An experiment was conducted during 2014-15 and 2015-16 at Vegetable Research farm, Bihar Agricultural University, Sabour (Bhagalpur) to study the existing genetic variability and to assess the genetic diversity among twenty-five genotypes of pointed gourd. The analysis of variance revealed highly significant differences among the genotypes for all the twenty-two characters studied. High heritability accompanied with high genetic advance as per cent of mean were recorded for total flavonoids (77.38 %) chlorophyll ‘b’ (72.85 %), total phenols (71.14 %), titratable acidity (57.45 %), number of marketable fruits per plant (53.52 %), yield of marketable fruits per plant (47.26 %), CUPRAC (46.58 %), carotenoids (40.11 %), number of primary branches per plant (38.95 %), chlorophyll ‘a’ (38.68 %), node number at which first female flower appears (37.58 %), average fruit weight (28.00 %) and fruit length (22.31 %). Correlation analysis revealed that the yield of marketable fruits per plant was significantly and positively correlated with fruit length (0.23), number of marketable fruits per plant (0.82) and titratable acidity (0.23). Path analysis further revealed that the number of marketable fruits per plant (0.8569), average fruit weight (0.3261), total phenol (0.1978), days to last fruit harvest (0.1709) and chlorophyll ‘b’ (0.1145) had positive direct effect on yield of marketable fruits per plant. Genetic diversity study grouped all the genotypes into six clusters and revealed that there was presence of considerable amount of genetic diversity in the materials for different yield and yield attributing traits. The cluster I contained the maximum of 8 genotypes followed by 6 genotypes in cluster II and V, three genotypes in cluster IV, and only one (mono-genotypic) in cluster III and VI, respectively. The highest intra-cluster distance was exhibited by cluster V (289.96) followed by cluster IV (187.57), II (159.29) and I (105.68). The highest inter cluster distance was observed between cluster III and V (766.29) followed by cluster IV and VI (758.47) and cluster V and VI (681.39). The above results indicated that these genotypes had maximum genetic diversity and useful for developing potential genotypes through selection for high yield coupled with desirable traits. The genotypes of cluster V showed the highest mean values for yield of marketable fruits per plant (3.96 kg) and titratable acidity (0.43 %) and the lowest mean value for days to first fruit harvest (153.94). The cluster VI exhibited highest mean value for average chlorophyll ‘a’ (24.13 mg/100g), chlorophyll ‘b’ (19.48 mg/100g), carotenoids (0.012 mg/100g), TSS (Total Soluble Solids) (3.42 0Brix) and free radical scavenging activity (52.57 %) while, the cluster IV exhibited highest mean value for fruit breadth (3.41 cm), number of marketable fruits per plant (119.50) and total sugar (1.56 %). The cluster III exhibited highest mean value for fruit length (8.16 cm), number of primary branches per plant (7.67), days to last fruit harvest (172.00), carotenoids (0.012 mg/100g) and total flavonoids (1.19 mg/100g) while, the cluster II exhibited highest mean value for ascorbic acid (28.03 mg/100g), total phenol (1.06 mg/100g), dietary fibre (5.40 mg/100g), CUPRAC (Cupric Ion Reducing Antioxidant Capacity) (2.27 %) and lowest mean value for node number at which first female flower appears (12.68). The promising genotypes viz; BRPG 13-30, BRPG 12-1, BRPG 12-8, BRPG 12-9, BRPG 12-7, BRPG 12-11 and Rajendra Parwal-1 were identified from cluster V and III on the basis of mean values for yield of marketable fruits per plant, number of primary branches per plant, days to last fruit harvest, fruit length, carotenoids, total flavonoids, titratable acidity and days to first fruit harvest for early maturity which could be utilized for the selection and development of high yielding genotypes. Among the twenty-two traits studied, maximum contribution was made by average fruit weight (49.33%) followed by yield of marketable fruits per plant (23.00%), number of marketable fruits per plant (15.00%), chlorophyll ‘b’ (5.67%) and total phenol (2.67%). Therefore, these characters may be given importance during selection and varietal development programme. Among the chemical treatment for reducing the post-harvest losses, Carnauba wax 1.0 % was found most effective for controlling low PLW (Physiological loss in weight), low TSS (Total Soluble Solids), high Chlorophyll and low carotenoids in almost all the genotypes except BRPG 12-7 in which BAP @ 200 ppm treatment was found to be the most effective. However, BRPG 12-9 was found promising among all genotypes for overall post- harvest treatments applied.ThesisItem Open Access Morphological and SCAR marker development for early sex determination in Pointed gourd (Trichosanthes dioica Roxb.)(Department of Horticulture (Vegetable & Floriculture), BAU, Sabour, 2019-04) Nand, Neetu; Kumar, RandhirPointed gourd (Trichosanthes dioica Roxb., 2n=2x=22), a perennial vegetable crop and commonly known as parwal/patal, have Indo-Malayan origin. It is said to be native of South East Asia and probably the Northern and Eastern states of India especially of West Bengal, Assam and Bihar. It has high economic value with export potential. It is mainly cultivated along the riverine belts of Bihar. Pointed gourd (Trichosanthes dioica Roxb) is an economically important cucurbit and is extensively propagated through vegetative means, viz; vine and root cuttings. The plant’s dioecious in nature and its vegetative mode of propagation makes its reproduction and multiplication labour intensive. Dioecy represents an inconvenience in pointed gourd breeding since at present there are only few reports distinguishing male and female plants prior to flowering. The use of molecular marker provides a quick and reliable identification of sex types in plants. RAPD (Random amplified polymorphic DNA) has been used previously for determining the gender of plants before flowering. The SCAR marker is one of the stable markers, generally derived from RAPD increase effectiveness of RAPD marker by selecting and redesigning primers whose priming sites occur in target sequence(s) of gene or organism at optimum distance. Therefore, the present study was undertaken to identify marker associated with male and female sex expression trait in T. dioica Roxb. followed by development of SCAR. The screening of genomic DNA samples representative of male and female plants of pointed gourd with RAPD was used to discover sex specific PCR amplification product. A total 40 RAPD primers were used for RAPD analysis, out of which 20 primers gave good results. Among these 20 primers, OPC-04 amplified a band of 400 bp specific to female lines. This RAPD marker was eluted, sequenced and the sequence was used to design primers for SCAR marker. From the sequence, a set of two SCAR primers (N6Fn and N7Fn) was designed to allow amplification of female specific region But, only single SCAR (N7Fn/r)amplify a product size of 400bp in female specific DNA.
