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ThesisItem Open Access Characteization and evaluation of nutmeg (Myristica fragrans Houtt.) accessions(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 2016) Vikram, H C; KAU; Mini Raj, NNutmeg (Myristica fragrans Houtt.) is an introduced crop to India. There exists tremendous variability in the nutmeg population in Kerala, which is the major nutmeg growing state in the country. Assessment of the existing variability is a prerequisite for taking up successful crop improvement programmes, which is very much limited in this tree spice. In this context, the present study entitled “Characterization and evaluation of nutmeg (Myristica fragrans Houtt.) accessions” was taken up exclusively with the specific objectives to characterize nutmeg accessions based on morphological, biochemical and molecular parameters so as to scale the variability in a multidimensional way. Select fifty nutmeg accessions from a core germplasm collected and maintained in a private plantation in the Chalakudy river basin, belonging to age of fifteen years, formed the material for the study. Among the select fifty accessions, forty two were females, four monoecious and four males. In the morphological characterization, 51 qualitative and 38 quantitative characters were recorded from two trees per accession. Biochemical characterization was done in the select seventeen distinct accessions. GC-MS profiling was done in kernel and mace oils. Biochemical constituents of fresh pericarp were estimated. Isozyme profiling was done for peroxidase and polyphenol oxidase enzymes. The molecular characterization was attempted with 21 RAPD and 12 ISSR primers after screening. A key for identification of an elite nutmeg tree was developed. A descriptor for nutmeg with a set of 51 qualitative and 38 quantitative parameters and descriptor states for each of these characters was developed as the first step. This is the first study of its kind to develop a minimal descriptor for nutmeg. The descriptor developed from the present study was simultaneously utilised for morphological characterization and evaluation of the accessions. Wide variability was noticed among the accessions for 47 out of 51 qualitative characters. Four characters viz., leaf margin, fruit pubescence, grooves on nut and nature of fruit dehiscence were noted as non variable characters and hence, these were not included for further analysis. Based on the qualitative characters, accessions were classified into 11 clusters at 66 per cent similarity level. Accessions differed significantly for all the quantitative characters except shelling percentage. Performance evaluation of the accessions brought out the superiority of accession 8, 9 and 22 for yield. The accessions showed high GCV, PCV, h2 and genetic gain for most of the characters. Number of fruits per tree, fruit set percentage, number of fruits per m2, fresh and dry weight of mace, mace volume as well ratio of nut to mace exhibited high genetic gain. Hence, selection programme based on these characters will be very effective in improving the base populations. Based on Mahalanobis D2 analysis, accessions were grouped into 10 clusters. Wide range of variation was observed in contents of volatile oil, oleoresin and fixed oil of kernel and mace. Based on these constituents accessions were grouped into 26 clusters, which indicated their distinct quality. Based on the results of the morphological characterization, seventeen distinct accessions were selected for further biochemical and molecular analysis. GC-MS analysis of kernel and mace oils exhibited 20 and 24 constituents respectively. Volatile oil composition exhibited wide variability for the major constituents viz., myristicin, elemicin, safrole and sabinene apart from the presence of some unique compounds. Grouping of the accessions was done based on the per cent content of these important compounds. Two accessions recorded high contents of both myristicin and elemicin whereas another two accessions were in the complimentary; belonging to low myristicin group. High sabinene combined with low myristicin was the intrinsic quality attribute of one of the accessions. Change, as well as addition/deletion of specific constituents was also noticed in the volatile oils after storage for one year. Accessions exhibited wide range of variation in the biochemical constituents of pericarp, a valuable information for the value addition of pericarp. Total phenol and tannins exhibited high variation. The accessions were ranked based on the content of biochemical constituents. Isozyme profiling using peroxidase enzyme produced four bands and that based on polyphenol oxidase exhibited three bands. Molecular markers could assess the variability among the accessions. The selected 21 RAPD primers produced a total of 164 amplicons of which 63.21 per cent were polymorphic. The 12 ISSR primers selected produced a total of 87 amplicons of which 69.44 per cent were polymorphic. Few unique bands were detected for specific characters. Inter cluster association of each of the qualitative clusters with other clustering patterns was worked out. The results indicated the differences as well as similarities of the qualitative clusters with other clustering patterns. Finally, key quantitative characters were identified based on their direct and indirect effect on yield as also economic importance. The statistical key thus developed using 13 key quantitative characters will serve as a preliminary tool for identification of an elite nutmeg tree.ThesisItem Open Access Diversity mapping and characterization of landraces of mango (Mangifera indica.L)(Department of Pomolgy and Floriculture, College of Horticulture, Vellanikkara, 2016) Harikumar, V; KAU; Parameswaran, N KThe project entitled “Diversity mapping and characterization of landraces of mango [Mangifera indica. L]” was undertaken at Pazhayannur region of Thrissur district of Kerala and under the department of Pomology and Floriculture, College of Horticulture,Vellanikkara, KAU during November 2012 to March, 2016. Selection of Pazhayannur region as the site of the present studies was based on a primary assessment conducted in this region earlier. The present investigations broadly envisaged the diversity mapping and digitization of mango LRs of this region, their characterisation, preparation of diversity registers and descriptors, documentation of associated indigenous traditional knowledge (ITK) and evolving appropriate integrated conservation and improvement strategies for the rare LRs spotted during the project implementation. Snow ball sampling method was used for locating the seedling mango LRs in different villages of the region and their spatial distribution was depicted through a series of GIS maps as per the geo co-ordinate readings. A total of 100 LRs could be thus located in the region and could be grouped in five GIS maps primarily based on their geographical position and further into the different rural hamlets of the major villages of the study site. A homestead based land use practice was largely noted in all these villages surveyed with many annual and perennial species planted and maintained around the homesteads where mango diversity confining to the homestead peripheries either as single plant or a component of poly crop system. The morphological characterization was carried out as per the standard descriptor for mango by IPGRI (2006) for different tree, leaf, inflorescence, fruit and biochemical parameters. Age of the trees surveyed spanned over a range of less than 20 years to more than 100 years and the trees were erect, spreading or drooping in their growth habit. A wide variation among the young leaves was noted with respect to the colour and it varied from light green, light green with brownish tinge, light brick red, reddish brown, and deep coppery tan. Flowering was noted from November to March making into early (November to December), midseason (January to February) and late season (from March) as noted among the different accessions and two intermediate periods between the seasons. Regular bearing was predominantly noticed in majority of the accessions but for few accessions which exhibited secondary/perpetual type of flowering. All most all the accessions produced terminal borne inflorescences but few accessions showed axillary and terminal emergence of inflorescence. The inflorescences were predominantly pyramidal in shape, followed by broadly pyramidal and conical in few. Inflorescence colour ranged from light green to crimson. Based on maturing period, the trees could be classified as early - if the fruits become mature for harvest by February, as intermediate - if ready for harvest by March to May, and as late - if ready by June. For pickling purpose, the stage for harvest varied from marble stage (for Kadu/tender manga pickle), to pre-mature (three-fourth) mature stage for Chethu manga. Fruit shapes varied from round, elliptic, obovoid, ovoid and oblong. Fruit colour was distinct and as a rare occurrence brownish colouration of the skin could also be noted in one of the accessions. Fruit weight varied from 44 g. to 634.82 g., pulp weight from 19.80 g to 419.50 g. and the thickness of the skin from 0.55 mm to 4.5 mm. With respect to the pulp colour, a great variation was observable viz., light yellow, yellow, yellow orange, light orange, dark orange, and greenish yellow. Presence of fibre in the fruit pulp was a unique feature of all the accessions. Pulp aroma was mild, intermediate or strong. Turpentine flavour which interferes with the edible quality of fruit was also noted in few . TSS of the ripe fruits varied from 7.6 to 23.65°brix and acidity from 0.1 to 1.49 percent. Polyembryony was also notable in few accessions with emerging seedlings per stone ranging from two to four. Principal component analysis and cluster analysis was carried out culminating in constructing a mathematical base for the entire survey. Four cell participatory analysis (FCA) conducted at the different villages, enabled the confirmatory identification of the common and rare mango LRs of thevillages primarily and the region as a whole. Overall diversity assessment clearly noted the predominance of the type Moovandan throughout the entire Pazhayannur region. Among the different villages maximum number of rare landraces could be spotted in Elanad village (39) followed by Vennur (19), Pazhayannur (19) and Vadakkethara (12). Accessions spotted from the extended locations of the survey (Tiruvilwamala and Panjal) were also added in to the rare group. ITK associated with these mango LRs with special reference to the conventional and traditional processing of fruits were also documented. A conceptual model for in situ conservation of the spotted LRs for the region could also worked out finally and a comprehensive village diversity register of mango LRs of the region in the specified format was prepared as a material for future reference. Initiatives were also taken up for the ex situ conservation of some rare mango LRs spotted. Scion material of rare LRs was collected and grafted plants prepared for planting in the mango gene sanctuary maintained by the department. Crossing and hybridization were also taken up during the project period involving selected LRs of the region as male parents with Moovandan and Neelum types maintained at the orchard of the college as female parents.ThesisItem Open Access Diversity mapping and characterization of landraces of mango (Mangifera indica. L)(College of horticulture, Vellanikara, 2016) Harikumar, V; KAU; Parameswaran, N KThe project entitled “Diversity mapping and characterization of landraces of mango [Mangifera indica. L]” was undertaken at Pazhayannur region of Thrissur district of Kerala and under the department of Pomology and Floriculture, College of Horticulture,Vellanikkara, KAU during November 2012 to March, 2016. Selection of Pazhayannur region as the site of the present studies was based on a primary assessment conducted in this region earlier. The present investigations broadly envisaged the diversity mapping and digitization of mango LRs of this region, their characterisation, preparation of diversity registers and descriptors, documentation of associated indigenous traditional knowledge (ITK) and evolving appropriate integrated conservation and improvement strategies for the rare LRs spotted during the project implementation. Snow ball sampling method was used for locating the seedling mango LRs in different villages of the region and their spatial distribution was depicted through a series of GIS maps as per the geo co-ordinate readings. A total of 100 LRs could be thus located in the region and could be grouped in five GIS maps primarily based on their geographical position and further into the different rural hamlets of the major villages of the study site. A homestead based land use practice was largely noted in all these villages surveyed with many annual and perennial species planted and maintained around the homesteads where mango diversity confining to the homestead peripheries either as single plant or a component of poly crop system. The morphological characterization was carried out as per the standard descriptor for mango by IPGRI (2006) for different tree, leaf, inflorescence, fruit and biochemical parameters. Age of the trees surveyed spanned over a range of less than 20 years to more than 100 years and the trees were erect, spreading or drooping in their growth habit. A wide variation among the young leaves was noted with respect to the colour and it varied from light green, light green with brownish tinge, light brick red, reddish brown, and deep coppery tan. Flowering was noted from November to March making into early (November to December), midseason (January to February) and late season (from March) as noted among the different accessions and two intermediate periods between the seasons. Regular bearing was predominantly noticed in majority of the accessions but for few accessions which exhibited secondary/perpetual type of flowering. All most all the accessions produced terminal borne inflorescences but few accessions showed axillary and terminal emergence of inflorescence. The inflorescences were predominantly pyramidal in shape, followed by broadly pyramidal and conical in few. Inflorescence colour ranged from light green to crimson. Based on maturing period, the trees could be classified as early - if the fruits become mature for harvest by February, as intermediate - if ready for harvest by March to May, and as late - if ready by June. For pickling purpose, the stage for harvest varied from marble stage (for Kadu/tender manga pickle), to pre-mature (three-fourth) mature stage for Chethu manga. Fruit shapes varied from round, elliptic, obovoid, ovoid and oblong. Fruit colour was distinct and as a rare occurrence brownish colouration of the skin could also be noted in one of the accessions. Fruit weight varied from 44 g. to 634.82 g., pulp weight from 19.80 g to 419.50 g. and the thickness of the skin from 0.55 mm to 4.5 mm. With respect to the pulp colour, a great variation was observable viz., light yellow, yellow, yellow orange, light orange, dark orange, and greenish yellow. Presence of fibre in the fruit pulp was a unique feature of all the accessions. Pulp aroma was mild, intermediate or strong. Turpentine flavour which interferes with the edible quality of fruit was also noted in few . TSS of the ripe fruits varied from 7.6 to 23.65°brix and acidity from 0.1 to 1.49 percent. Polyembryony was also notable in few accessions with emerging seedlings per stone ranging from two to four. Principal component analysis and cluster analysis was carried out culminating in constructing a mathematical base for the entire survey. Four cell participatory analysis (FCA) conducted at the different villages, enabled the confirmatory identification of the common and rare mango LRs of thevillages primarily and the region as a whole. Overall diversity assessment clearly noted the predominance of the type Moovandan throughout the entire Pazhayannur region. Among the different villages maximum number of rare landraces could be spotted in Elanad village (39) followed by Vennur (19), Pazhayannur (19) and Vadakkethara (12). Accessions spotted from the extended locations of the survey (Tiruvilwamala and Panjal) were also added in to the rare group. ITK associated with these mango LRs with special reference to the conventional and traditional processing of fruits were also documented. A conceptual model for in situ conservation of the spotted LRs for the region could also worked out finally and a comprehensive village diversity register of mango LRs of the region in the specified format was prepared as a material for future reference. Initiatives were also taken up for the ex situ conservation of some rare mango LRs spotted. Scion material of rare LRs was collected and grafted plants prepared for planting in the mango gene sanctuary maintained by the department. Crossing and hybridization were also taken up during the project period involving selected LRs of the region as male parents with Moovandan and Neelum types maintained at the orchard of the college as female parents.
