http://103.7.193.12:8080/xmlui/handle/123456789/137 Sun, 25 Oct 2026 10:19:26 GMT 2026-10-25T10:19:26Z http://103.7.193.12:8080/xmlui/handle/123456789/2201 SELECTION OF HEAT TOLERANT PARENTS AND THE DEVELOPMENT OF SUPERIOR HYBRIDS IN BOTTLE GOURD [Lagenaria siceraria (Mol.) Standl.] ISLAM, MD. SHAFIQUL Rising summer temperatures in Bangladesh severely constrain bottle gourd productivity, necessitating the identification of heat-tolerant parents and the development of superior hybrids. To address this challenge, a comprehensive research program was conducted from 2022 to 2025 at the BRAC Vegetable Research Center, Dinajpur, involving fifty-eight (58) genetically diverse bottle gourd genotypes. The study aimed to assess genetic variability and screen heat-tolerant genotypes, identify superior parents through combining ability, and develop heterotic hybrids under heat stress. Initially, the 58 genotypes were evaluated under both optimum (Rabi) and heat-stress (Kharif) environments for morphological, yield contributing, and quality traits. Wide and significant genetic variability was observed for days to first female flower appearance, node number at first female flower appearance, days to first edible fruit harvest, fruit length, fruit diameter, number of fruits per plant, fruit weight, fruit yield per plant, total soluble solids, dry matter content, and ascorbic acid content. High heritability coupled with high genetic advance for most traits indicated the predominance of additive gene action and substantial scope for genetic improvement through selection. Correlation and path analyses identified number of fruits per plant, fruit weight, and fruit diameter as primary yield determinants, with earliness contributing indirectly, establishing these traits as key selection criteria under heat stress. Heat tolerance was assessed using combined stress tolerance indices of major yield-contributing traits. Based on indices values, ranking, and cluster analysis, genotypes were classified into 21 heat-tolerant, 18 mid-tolerant, and 19 susceptible groups. From these, 20 tolerant and two mid-tolerant genotypes were selected for further evaluation through line × tester analysis under heat stress conditions. Combining ability analysis identified several parents with desirable general combining ability (GCA) effects for earliness, fruit size, yield components, and yield per plant. Based on per se performance and GCA ranking, six genotypes with BG-01, BG-16, and BG-21 as strong general combiners and BG-42, BG-55, and BG-53 as moderate but trait-specific good combiners were selected for a 6 × 6 full diallel mating design. Diallel analysis conducted during Kharif 2025 under heat stress showed highly significant GCA, SCA, and reciprocal effects for all studied traits, confirming the involvement of additive, dominance, and maternal genetic components, as well as the importance of cross direction in hybrid performance. Among the parents, BG-53 and BG-21 were identified as superior general combiners for fruit yield and major yield determinants. Heterosis analysis revealed significant positive heterosis over mid-parent, better-parent, and standard checks for yield and yield-contributing traits under heat stress. The hybrid BG-53 × BG-16 exhibited maximum heterosis for number of fruits per plant and fruit yield per plant. BG-53 × BG-01 recorded the highest heterosis for average fruit weight along with substantial yield advantage. BG-55 × BG-42 showed significant heterosis for fruit diameter along with favorable yield and quality traits. Crosses BG-01 × BG-21 and BG-21 × BG-53 combined desirable earliness with high yield heterosis, indicating strong dominance and over-dominance effects under heat-stress conditions. Genotypes BG-53 (mid-tolerant, early, and prolific) and BG-21 (tolerant, with higher fruit weight and yield) were identified as key parental lines for heat-stress breeding programs. The hybrids BG-53 × BG-16, BG-53 × BG-01, BG-01 × BG-21, BG-21 × BG-53, and BG-55 × BG-42 were selected as promising for potential commercial hybrid development under heat stress in Bangladesh. SELECTION OF HEAT TOLERANT PARENTS AND THE DEVELOPMENT OF SUPERIOR HYBRIDS IN BOTTLE GOURD [Lagenaria siceraria (Mol.) Standl.]; Dissertation submitted to the Department of Genetics and Plant Breeding Hajee Mohammad Danesh Science and Technology University, Dinajpur in partial fulfillment of the requirements for the Degree of DOCTOR OF PHILOSOPHY IN GENETICS AND PLANT BREEDING BY MD. SHAFIQUL ISLAM, Registration No: 1105072, DEPARTMENT OF GENETICS AND PLANT BREEDING, HAJEE MOHAMMAD DANESH SCIENCE AND TECHNOLOGY UNIVERSITY DINAJPUR-5200, BANGLADESH; AUGUST 2026. Sat, 01 Aug 2026 00:00:00 GMT http://103.7.193.12:8080/xmlui/handle/123456789/2201 2026-08-01T00:00:00Z http://103.7.193.12:8080/xmlui/handle/123456789/2159 DEVELOPMENT AND EVALUATION OF ADVANCED GENERATIONS TO EVOLVE HIGH YIELDING VARIETIES OF JUTE (Corchorus olitorius L.) Biswas, Sanjoy Kumar Several experiments were conducted on Tossa jute (Corchorus olitorius L) at Jute Agricultural Experimental Station, Jagir, Manikgonj during 2015-2018. A total of 53 diverged genotypes were included to study on 11 characters like plant height (cm), base diameter (mm), green bark thickness (mm), leaf length (cm), leaf width ( mm), leaf angle (0), petiole length (cm), green weight with leaves (g), green weight without leaves (g), fibre weight (g) and stick weight (g) to create segregants from where outstanding advanced lines may evolve for the development new varieties. Significant variations were observed for all characters among the genotypes. Simultaneous consideration of high mean performance and high heritability showed by green bark thickness, green weight without leaves, plant height and base diameter are necessary to the breeders for improving Tossa jute through selection breeding. The fifty three genotypes were grouped into five clusters by D2 statistics which were confirmed through superimposing corresponding PCAs. The cluster III accommodated the highest number of genotypes (18) and cluster I included only three genotypes. Both upper and lower magnitudes of expression for characters like base diameter, plant height, green bark thickness and late flowering were considered to produce diversified segregants. Accordingly 8 parents, O-9897, O-795, JRO-524, Acc-2381, Acc-3423, Acc.-3438 Acc-3533 and Acc-3860 were selected simultaneous consideration of clustering and phenotypic acceptance for full diallel crossing program and 8 x 7=56 experimental hybrids were produced. On the way of evaluation, mean performances, correlation coefficients and path analysis of each character on fibre yield were estimated to assess the nature relation pertained among the characters. In general, genotypic correlation coefficients were higher than concurrent phenotypic correlation coefficients, indicated preponderance effects genetic makeup upon expression of the characters. Out of 8 parents, 4 parents Acc-2381, Acc 3423, Acc-3533 and Acc-3860 produced higher fibre weight but positive and significant GCAs were estimated for O-795, JRO-524 Acc-3533 and Acc-3860. Besides, consideration means and GCAs, two lines Acc-3533 and Acc-3860 also appeared as good combiners in both directions hybridization program. Reciprocal crosses apparently exhibited significant cytoplasmic gene effects to express the selected characters during field evaluation. Seven hybrid combinations from normal and another seven combinations from reciprocal crosses revealed significant and positive SCAs effects for fibre weight/plant. The positive and significant SCAs were resulted due to additive and non-additive interactions of the concerned alleles. The joint consideration of positive and significant GCAs and SCAs the crosses P2 x P6 (O-795 x Acc-3438), P2 x P7 (O-975 x Acc-3533), P3 x P4 (JRO-524 x Acc-2381), P3 x P5 (JRO-524 x Acc-3423), P7 x P8 (Acc-3533 x Acc-3860), P5 x P2 (Acc-3423 x O-975) , P6 x P3 (Acc-3438 x JRO-524), P7 x P5 ( Acc-3533 x Acc-3423, P8 x P2 (Acc-3860 x O-975) and P8 x P4 (Acc-3060 x Acc-2381) were outstanding for improving fibre yield potential in Tossa jute through cross breeding programs. From each of the F2 generation against a cross a total of 300 plants were initially selected and then variability parameters based 10% plants (30 plants) were selected to advance in next generation. The segregating populations derived from P8 x P4 (Acc-3060 x Acc-2381) and P3 x P4 (JRO-524 x Acc-2381) might produce superior segregants in advanced generation, therefore, the breeders may exploit the segregants to operate either pedigree or bulk method to evolve outstanding advanced lines of Tossa jute. DEVELOPMENT AND EVALUATION OF ADVANCED GENERATIONS TO EVOLVE HIGH YIELDING VARIETIES OF JUTE (Corchorus olitorius L.); A PhD DISSERTATION By Sanjoy Kumar Biswas, Registration No. 1505306, DEPARTMENT OF GENETICS AND PLANT BREEDING, HAJEE MOHAMMAD DANESH SCIENCE AND TECHNOLOGY UNIVERSITY DINAJPUR-5200; NOVEMBER, 2021. Mon, 01 Nov 2021 00:00:00 GMT http://103.7.193.12:8080/xmlui/handle/123456789/2159 2021-11-01T00:00:00Z http://103.7.193.12:8080/xmlui/handle/123456789/2156 STUDY ON PRODUCTIVE AND REPRODUCTIVE PERFORMANCES AND SEMEN QUALITY OF ASEEL CHICKEN PRAMANIK, Md. AHSAN HABIB Aseel, Naked Neck, and Red Junglefowl are the most important chicken genetic resources in Bangladesh. However, due to the unconsciousness of the farmers, uncontrolled crossing with other indigenous chickens, lack of proper conservation programs these are close to extinction. To conserve the extinct species the various ways were adopted in developed countries. As the first initiative of in vitro conservation of the poultry genetic resources, the present study was undertaken with four different distinct experiments to know the productive and reproductive performance of Aseel chicken and to study semen quality, sperm motility, biokinetic characteristics, sperm cryo-survivability by pre-freezing addition of honey as the possible cryo-protectant. Semen quality and the effect of honey on semen cryopreservation were evaluated by measuring sperm motility and biokinetic parameters with Computer Semen Analysis (CASA). The Aseel, Naked Neck and Red Junglefowl chickens were reared in open sided house in semi-scavenging condition at the Advanced Avian Research Farm, HSTU, Dinajpur. The Aseel sperm were cryopreserved using different level of honey where Glycerol and DMSO were also used as the positive controls. Considering productive and reproductive characteristics of the Aseel chicken showed almost similar performances of other chicken genetic resources but in some cases Aseel performed better. The semen color obtained from Aseel cocks was creamy white and showed a normal appearance and proved the semen quality was normal. The volume of semen per ejaculation and the pH were almost similar to others’ semen. Sperm motility was also observed normal in relation to motility and progressive motility along with other biokinetic characteristics. Considering the motility and percentage of the progressively motile sperm, the semen samples might be stored for up to 2 hours in good condition for insemination. Pre-freezing addition of 3% honey showed the satisfactory results in maintaining cryo-survivability. The productive and reproductive characteristics did not vary in case of natural and artificial insemination with fresh and diluted semen. Moreover, the result showed that the addition of 3% honey in Ringer’s solution performed as a cryoprotective agent which may help to cryopreserve Aseel roosters’ semen as the native chicken genetic resource and revealed that honey might has the cryoprotective properties. Therefore, the study concluded that the pre-freezing addition of honey improved the cryo-survivability of Aseel’s sperm and suggested for in vitro conservation of chicken genetic resources available in Bangladesh. STUDY ON PRODUCTIVE AND REPRODUCTIVE PERFORMANCES AND SEMEN QUALITY OF ASEEL CHICKEN; Dissertation submitted By Md. AHSAN HABIB PRAMANIK, Registration No.: 1805486; Doctor of Philosophy (PhD) in Genetics and Animal Breeding. Department of Genetics and Animal Breeding. Hajee Mohammad Danesh Science and Technology University Dinajpur-5200, Bangladesh; January 2023. Sun, 01 Jan 2023 00:00:00 GMT http://103.7.193.12:8080/xmlui/handle/123456789/2156 2023-01-01T00:00:00Z http://103.7.193.12:8080/xmlui/handle/123456789/2150 MULTIVARIATE ANALYSIS AND EVALUATION OF HYBRIDS WITH THEIR PARENTS IN FINE RICE Haque, Md. Monzurul Twenty five fine rice genotypes including thirteen non-aromatic and twelve aromatic cultivars were evaluated for fifteen quantitative characters to select the most yield enhancing characters as well as the diverged cultivars for hybridization. The mean performances and genetic parameters of the characters were separated through univariate analysis; the most yield promoting characters were selected by bivariate and multivariate analyses and desirable parents were selected by univariate and multivariate analyses. Though high heritability was estimated for most the characters but the highest genetic advance was estimated against spikelets/panicle (125.74). Effective tillers/hill, spikelets/panicle showed positive and significant, and plant height, days to 50% flowering and days to maturity showed negative and significant correlation coefficients with yield. Upon partitioning the total phenotypic correlation coefficients with yield, 1000-grain weight exerted the highest direct effect (0.84), followed by spikelets/panicle (0.67) and effective tillers/hill (0.61), therefore, these three characters appeared as the predominant yield accelerating characters in fine rice. A total of thirty selection indices were constructed based on five characters including yield and the highest relative efficiency of simultaneous selection was gained from I12345 (223.31%). Twenty five cultivars were grouped into six clusters by D2 statistics and six cultivars such as Kataribhog, Salna, Ranjit, Begunbichi, Chinigura and Kalozira were selected based on clustering as well as rank distribution of the cultivars. The selected parental lines were evaluated both in research and farmer’s fields to assess their tangible performance for the selected characters. The estimated yield gap between the research and the farmer’s fields was 0.86 t/ha. The selected cultivars produced significantly higher effective tillers/hill, spikelets/panicle and yield in the research field than that of farmer’s field. However, the potentiality of the segregants was predicted in the course of such comparison. It was initially aimed to develop fifteen experimental hybrids through a diallel model, but eight hybrids were finally produced from these six parental lines. The cytogenetical barrier against the failure of seven hybrids was investigated. The non remarkable karyotypic disharmony in the parents may not be the principal cause behind the failure of seven hybrids; other reasons like genetical, physiological and environmental factors may be responsible to create such partial hybridization failure that need to be further investigation. The eight hybrids were evaluated and their competence was measured by three criteria of heterosis. The aroma contents in the hybrids and their parents were compared. Out of eight hybrids, three were non-aromatic and five were aromatic, in which the highest aroma was assessed in the F1 of Kataribhog × Salna and F1 of Kataribhog × Chinigura, hence consideration of yield and aroma content these two hybrids may bring to obtain desirable segregants. MULTIVARIATE ANALYSIS AND EVALUATION OF HYBRIDS WITH THEIR PARENTS IN FINE RICE; A PhD DISSERTATION by Md. Monzurul Haque, Registration no. : 1005053; DEPARTMENT OF GENETICS AND PLANT BREEDING, FACULTY OF AGRICULTURE, HAJEE MOHAMMAD DANESH SCIENCE AND TECHNOLOGY UNIVERSITY, DINAJPUR-5200; FEBRUARY, 2014. Sat, 01 Feb 2014 00:00:00 GMT http://103.7.193.12:8080/xmlui/handle/123456789/2150 2014-02-01T00:00:00Z