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Item Assessment of diversity in native orchids(Department of Floriculture and Landscaping, College of Agriculture, Vellanikkara, 2021) Shuhda Nalakath; Anupama, T VA study entitled ‘Assessment of diversity in native orchids’ was conducted in the Department of Floriculture and Landscaping, College of Agriculture, Vellanikkara, from July 2019 to June 2020. The objective of the study was to assess the diversity among the native orchid accessions by evaluating their morphological characters. The morphological characters of twenty three native orchid accessions conserved under the Department of Floriculture and Landscaping were studied. Based on the growth habit, five accessions were classified as monopodial orchids and 18 accessions were classified as sympodial orchids. The accessions viz; Acampe praemorsa, Aerides crispa, Rhynchostylis retusa, Vanda thwaitesii and Luisia sp. were grouped under monopodials, and the accessions belonging to genera viz; Dendrobium, Eria, Pholidota, Bulbophyllum, Flickingeria, Coelogyne, Cymbidium and Oberonia were grouped under sympodials. The quantitative vegetative characters varied significantly among the accessions. Among the monopodial accessions, Acampe praemorsa (VKA/NOR-3) recorded maximum plant height (43.36 cm), internodal length (2.40 cm), leaf length (23.94 cm), leaf width (2.76 cm) and leaf sheath length (3.60 cm). In sympodial orchid accessions, plant height recorded was highest for Dendrobium moschatum (VKA/NOR-37) (75.20 cm). The highest plant spread was observed in Luisia sp. (VKA/NOR-7) (1571.28 sq.cm) among monopodials, whereas Dendrobium crumenatum (VKA/NOR-34) (3979.22 sq.cm) was superior in terms of this parameter among the sympodials. These two species also recorded maximum number of leaves compared to other accessions (89.20 and 95.80). Among sympodials, Cymbidium accessions were observed to be superior in terms of the parameter leaf length, and maximum leaf length was recorded in Cymbidium ensifolium (VKA/NOR- 43) (43.50 cm). Variability was also noted among the accessions with regard to qualitative vegetative characters viz; leaf shape, leaf orientation, leaf arrangement and root colour. Nine native orchid accessions bloomed during the study period were evaluated for their floral characters. Among them Dendrobium crumenatum (VKA/NOR-34) exhibited three flowering seasons (April-May, October, Dec-Jan). The accessionPholidota imbricata (VKA/NOR-29) recorded highest spike length as well as rachis length (49.66 cm and 23.50 cm). The number of florets per spike recorded was maximum in Rhynchostylis retusa (VKA/NOR-4) (99.33). Largest showy flower among the accessions was observed in Dendrobium moschatum (VKA/NOR-37) with maximum flower size of 54.37 sq.cm, highest petal length (3.98 cm), petal width (2.94 cm), petal to petal distance (6.89 cm), length of dorsal sepal (3.49 cm), width of dorsal sepal (1.63 cm), and length of lateral sepal (3.01 cm). Lip (labellum) is the most attractive feature of an orchid flower and is found to have variations. The accession Dendrobium crumenatum (VKA/NOR-34) (2.75 cm) was found to have maximum lip (labellum) length and Dendrobium moschatum (VKA/NOR-37) (2.28 cm) was found to have maximum lip (labellum) width. The longevity of spike on plant recorded was maximum for Dendrobium ovatum (VKA/NOR-60) (12.00 days), and the longevity of florets on spike recorded was maximum in Acampe praemorsa (VKA/NOR-3) (19.00 days). The pollen viability (%) was found to be more than 90 percentage for all the accessions flowered and it was noted maximum for Rhynchostylis retusa (VKA/NOR- 4) (98.27 percentage). Cluster analysis at 75 percentage similarity among the accessions done based on their quantitative characters resulted in different clusters containing accessions with similar morphological traits. Among sympodials most of the accessions were grouped under Cluster A with common characters for plant spread as well as leaf width. With respect to quantitative floral characters most of the accessions were grouped under Cluster A and they showed similarity for characters such as number of spikes, flower size, petal length and width, petal to petal distance, dorsal sepal to lip distance, length and width of lateral sepal and dorsal sepal, and also length and width of lip and column. Wide variation was observed in spike orientation, petal shape, petal curvature and lip shape. The accessions were also noted for the presence of flower fragrance, and it was recorded in Dendrobium crumenatum (VKA/NOR-34), Dendrobium fimbriatum (VKA/NOR-27), Dendrobium moschatum (VKA/NOR-37), Acampe praemorsa (VKA/NOR-3), Rhynchostylis retusa (VKA/NOR-4) and Eria fragrans (VKA/NOR- 25). The floral parts of the accessions also exhibited different sepal, petal, lip and column colouration.Based on morphological evaluation, superior accessions were identified for commercial traits and accordingly they were grouped as pot plant types (VKA/NOR-4, VKA/NOR-39, VKA/NOR-29), fragrant flowered types (VKA/NOR-27, VKA/NOR- 34, VKA/NOR-37, VKA/NOR-4, VKA/NOR-3) accessions with long spike (VKA/NOR-4, VKA/NOR-29), greater number of florets (VKA/NOR-4, VKA/NOR- 29) and highest longevity (VKA/NOR-29, VKA/NOR-3). Diversity assessment using cluster analysis has revealed the variability as well as similarity existed among native orchid accessions on the basis of their morphological characters. The findings are highly useful for identification of superior accessions which can be utilized for crop improvement programmes and also for commercial floriculture.Item Response of Ascocenda orchid to growth regulator and micronutrients(Department of Floriculture and Landscaping, College of Horticulture, Vellanikkara, 2019) Jesabel George; Shobhana, AA study entitled ‘Response of Ascocenda orchid to growth regulator and micronutrients’ was carried out at Department of Floriculture and Landscaping, College of Horticulture Vellanikkara, from May 2018 to May 2019. Ascocenda is a monopodial, epiphytic, bigeneric hybrid, which is mainly grown as pot plant in hanging baskets using bricks, charcoal, coconut husk pieces etc. as growing media. The objective of the study was to evaluate the influence of foliar application of different micronutrient treatments on growth and yield of Ascocenda orchid. The experiment was conducted with eleven treatments viz., 0.01% zinc + 150 ppm benzyl adenine + PoP (T1), 0.025% zinc + 150 ppm benzyl adenine + PoP (T2), 0.01% manganese + 150 ppm benzyl adenine + PoP (T3), 0.025% manganese + 150 ppm benzyl adenine + PoP (T4), 0.01% boron + 150 ppm benzyl adenine + PoP (T5), 0.025% boron + 150 ppm benzyl adenine + PoP (T6), 0.01% iron + 150 ppm benzyl adenine + PoP (T7), 0.025% iron + 150 ppm benzyl adenine + PoP (T8), 0.01% molybdenum + 150 ppm benzyl adenine + PoP (T9), 0.025% molybdenum + 150 ppm benzyl adenine + PoP (T10), 150 ppm benzyl adenine + PoP (T11 – control). Three month old tissue cultured plants of Ascocenda var. Big Suksamran were used for the study. The micronutrients were applied at fortnightly intervals and benzyl adenine was applied at monthly intervals. Application of NPK (3:1:1) weekly twice @ 0.2% and cow dung slurry (1:5) at monthly intervals was given to all treatments as per PoP recommendation of KAU. Observations were taken at monthly intervals. The results indicated that foliar application of 0.025% manganese along with 150 ppm BA and recommended dose of NPK (T4) was best for improving plant height. The maximum plant height obtained at 12MAP was 8.86 cm. This was followed by T5 (8.81 cm) and T3 (8.63 cm) which were statistically on par with T4. The maximum shoot diameter was observed in T5 (10.20 mm) at 12 MAP which was on par with T4 and T3 (9.96 mm and 9.84 mm respectively). The treatment T3 was superior in terms of leaf characters like leaf length and leaf area up to 7 MAP and thereafter these parameters were highest in treatment T5. However, there was no significant difference between T5 and T3 in terms of leaf length at 12 MAP (16.70 cm and 16.48 cm respectively). The highest leaf area at 12 MAP was observed in T5 (23.17 cm2) followed by T3 (22.73 cm2). Number of leaves and leaf breadth were found highest with the application of 0.01% boron along with 150 ppm BA and recommended dose of NPK. A maximum of 13.69 leaves were observed in T5 at 12MAP. The maximum leaf breadth observed in T5 after 12 months of planting was 1.52 cm, which was closely followed by T3 and T4 (1.51 cm each), and no significant difference between these three treatments could be noticed. Regarding interval of leaf production, only 4 treatments (T3, T4, T5, and T11) could produce the highest number of eight leaves, within a period of 386 days. Among these, T4 took the shortest period of 337.45 days to produce the 8th leaf. T10 produced only five leaves within a period of 386 days. Among the root parameters, highest root length was observed in T3 (0.01% manganese + POP + 150 ppm BA) at 12 MAP (26.59 cm) whereas the treatment T4 (0.025% Mn + PoP + 150 ppm BA) was superior in terms of number of roots and root diameter. The best treatment with respect to number of roots varied during initial months, even though, from 6 MAP onwards, highest number of roots was observed in T4 with a value of 10.28 at 12 MAP. In the case of root diameter, a highest of 2.91 mm was recorded in T4 at 12 MAP, which was on par with T8 (2.86 mm), T3 (2.84 mm) and T5 (2.82 mm). Among the eleven treatments, T3 (Mn 0.01% + PoP + 150ppm BA), T4 (Mn 0.025% + PoP + 150ppm BA), and T5 (B 0.01% + PoP + 150ppm BA)were found to be best for improving the vegetative characters of Ascocenda orchid, while application of Mo @ 0.025% (T10) at fortnightly intervals was inhibitory to the plants in terms of all the vegetative characters studied. The objective of studying the floral and postharvest characters could not be achieved since the plant did not bloom within the period of study.Item Cryoconservation of koovalam (Aegle marmelos L.Corr.) by encapsulation-dehydration technique(Department of Plant Biotechnology, College of Agriculture, Vellayani, 2018) Deepa, E; Deepa S NairThe study entitled “Cryoconservation of Koovalam (Aegle marmelos L. Corr.) by encapsulation-dehydration technique,” was carried out in the Department of Plant Biotechnology, College of Agriculture, Vellayani during 2015-2017. The objectives of the present study were to standardize a cryopreservation protocol for Aegle marmelos using encapsulation and dehydration technique and to assess the genetic fidelity of plantlets regenerated from encapsulated axillary buds after cryostorage, using molecular markers. Investigation was carried out in three phases viz., enhancement of multiplication rate, standardization of in vitro conservation using the encapsulation-dehydration technique and assessment of genetic fidelity of the regenerated plantlets using ISSR markers. Single node segments with axillary buds from in vitro maintained cultures were used as the explants in all the experiments. Among the twelve combinations of auxins and cytokinins were tried, MS (Murashige and Skoog, 1962) medium supplemented with BA 2 mg L-1 + IBA 0.5 mg L-1 was found to be the best treatment with respect to shoot multiplication (9.33 shoots per explant). The additives chitosan (CH), thidiazuron (TDZ) and adenine sulphate (AdS) at different concentrations were supplemented in two different media i.e. 1) hormone free MS medium and 2) MS + BA 2 mg L-1 + IBA 0.5 mg L-1 to study their effect on shoot proliferation. The best shoot proliferation response obtained for each additives were MS + BA 2 mg L-1 + IBA 0.5 mg L-1 + chitosan 10 mg L-1 (35.66 shoots per explant), MS + AdS 60mg L-1 (5.33 shoots per explant) and MS + BA 2 mg L-1 + IBA 0.5 mg L-1 + TDZ 0.02 mg L-1 (20.00 shoots per explant). Even though higher shoot proliferation was observed in CH and TDZ supplemented media, they exhibited morphological abnormalities. Normal shoots were obtained with AdS supplemented medium, but shoot proliferation was less compared to MS + BA 2 mg L-1 + IBA 0.5 mg L-1. Hence MS + BA 2 mg L-1 + IBA 0.5 mg L-1 was used as basal medium for cryopreservation studies. Encapsulation-dehydration technique of cryopreservation involved various steps like preconditioning, encapsulation, pre-culture, dehydration (desiccation), thawing and recovery. Nodal segments with single axillary buds were used as the explant. In preconditioning experiment, PC2 (sucrose 0.1M in semi solid MS for 7 days) was selected as the best preconditioning treatment, which produced maximum shoot proliferation (5.50 shoots per culture) when cultured on basal medium. Among different encapsulation treatments, maximum shoot proliferation of (6.66 shoots per culture) was obtained in the beads formed with sodium alginate 3.5 per cent in modified MS medium and calcium chloride 100 mM, when cultured on modified basal medium (½ MS + BA 2 mg L-1 + IBA 0.5 mg L-1). Pre-culture experiments were conducted using preconditioned and encapsulated explants. The pre-culture treatment selected was liquid MS medium supplemented with sucrose 0.5 M and DMSO 3 per cent for 3 days, which gave maximum shoot proliferation (3.66 shoots per explant) in modified basal medium. The preconditioned, encapsulated and pre-cultured beads were subjected to 0 to 7 h of desiccation under laminar airflow. The moisture content declined from 82 per cent to 12.60 percent on 7 h of desiccation. The desiccated beads were then cryopreserved in liquid nitrogen for 2h, followed by thawing for 30-60s at 40oC and inoculated on to recovery medium ½ MS + BA 2 mg L-1 + IBA 0.5 mg L-1. Survival (66.67 per cent) and regeneration (50 per cent) could be obtained only at 6h of desiccation when the moisture content was 19.50 per cent. The beads when stored in liquid nitrogen for different duration did not show any significant variation with respect to survival and regeneration. The genetic fidelity of plantlets regenerated from encapsulated axillary buds subjected to cryostorage were analysed using ISSR markers. Among the nine primers tried, four primers UBC 807 (AGAGAGAGAGAGAGAGT), UBC 840 (GAG AGA GAG AGA GAG AYT), UBC 847 (CACACACACACACACART) and UBC 826 (ACACACACACACACACC) that gave scorable (5-7) bands were selected for the study. The ISSR banding patterns of the cryoregenerated plantlets and control plants were identical, which indicated the genetic stability. This study was successful in developing a protocol for cryopreservation using encapsulation-dehydration technique in A. marmelos with 50 per cent regeneration efficiency.Item Characterisation and conservation of promising genotypes of orchids from central western ghats(Department of Plant Breeding and Genetics,College of Agriculture, Padannakad, 2016) Yusuf Abbas; Sujatha, RItem Physiological approaches for enhancing the ex vitro establishment of tissue cultured orchid (Phalaenopsis sp.)(Department of Plant Physiology, College of Agriculture, Vellayani, 2019) Sayooj, S; Viji, M MItem Evaluation of fragrant vandaceous orchids for ornamental traits(Department of Floriculture and Landscaping, College of Horticulture, Vellanikkara, 2017) Deepa, T; Geetha, C KTwenty five fragrant vandaceous orchids were evaluated in the Department of Floriculture and Landscaping during the period from June 2016 to May 2017 with the objective of classifying them based on aesthetic and economic parameters for commercial exploitation as value added plants. The varieties exhibited wide variation in both vegetative and floral characters. Considering quantitative characters, Vasco Crownfox Red Gem recorded the maximum plant height (68.73cm), spread (52.23cm), internodal length (1.95cm) and leaf length (33.83cm). V. Pranerm Prai x V. tessellata showed maximum shoot girth (4.99cm), leaf area (105.54cm2), leaf number (37) and root length (181.75cm). The least values for all these characters were for Neostylis Lou Sneary. Duration from spike emergence to opening of florets was the maximum in Ascda Peggy Foo x Rhyn. Coelestis Blue and minimum in Neostylis Lou Sneary. Maximum spike longevity was recorded in V. Rothschildiana (29.30 days) whereas it was minimum in Rhy Sri Siam x Rhy gigantia (7.50 days). Interval of spike production was also the longest in Ascda. Peggy Foo x Rhyn. coelestis Blue and the minimum in Rhynchorides Bangkok Sunset. Spike production was the maximum in Neostylis Lou Sneary, followed by Ascda Srichai and Vasco Crownfox Red Gem. The varieties/ hybrids varied with regard to blooming period. The peak flowering was from May to July. Longer spike and rachis were noticed in Aerides quinque Vulnera Rhy. Coelestis. Vasco Blue Bay Pink had the highest number of florets/ spike and the shortest internodal length. Largest flowers were observed in V. Rothschildiana. Petal and labellum of the varieties also exhibited different colour patterns such as uniform, spotted, netted, tessellated and shaded. All the evaluated varieties were fragrant and were categorized based on different notes such as floral, fruity, spicy, green, sweet and miscellaneous. Fragrance was very faint in V. Rothschildiana whereas it was musty in Darwineria Cream Puff. With respect to the post-harvest characters longevity (vase life) was the maximum in V. JVB X Ascda Yip Sum Wah (17.30 days) and individual floret life (8.13 days) in V. Rothschildiana. Colour and pigmentation, texture, shape, pattern and size of florets as well as arrangement of florets on the spike were considered for the visual evaluation of a variety for use as cut flower. Considering the overall qualitative and quantitative attributes, Vascostylis Crownfox Red Gem, Vasco Blue Bay Blue, Rhynchorides Bangkok Sunset, V. Mimi Palmer, V. JVB X Ascda Yip Sum Wah and Vasco Blue Bay Pink were excellent for cut flower production. Plant quality evaluation was done based on fullness, growth and visual appearance, flower colour and pigmentation, spike longevity, shape and arrangement of foliage during the growth period. Fragrance scoring was also done based on intensity and diffusiveness, newness and beautifulness of fragrance. Based on the flowering phenology, four phenophases, namely, November – January, February – April, May – July and August – September were recorded and the varieties were categorized accordingly. Side-runs with different colour combinations were observed within a phenophase. The varieties were also categorized on the basis of flower colour, number of florets/ spike and floret size, longevity of spike on the plant , number of spikes produced / year and fragrance. Considering overall quantitative and qualitative characteristics, the evaluated varieties/ hybrids were categorized for cut flower, indoor and outdoor gardens for commercial exploitation as value added plants. The fragrance also makes it a novelty in landscaping to create a peaceful, relaxing environment.Item Refinement of nutrient management practices in dendrobium orchids(Department of Floriculture and Landscapingp, College of Horticulture, Vellanikkara, 2017) Shilpa, P; Mini SankarTwenty five fragrant vandaceous orchids were evaluated in the Department of Floriculture and Landscaping during the period from June 2016 to May 2017 with the objective of classifying them based on aesthetic and economic parameters for commercial exploitation as value added plants. The varieties exhibited wide variation in both vegetative and floral characters. Considering quantitative characters, Vasco Crownfox Red Gem recorded the maximum plant height (68.73cm), spread (52.23cm), internodal length (1.95cm) and leaf length (33.83cm). V. Pranerm Prai x V. tessellata showed maximum shoot girth (4.99cm), leaf area (105.54cm2), leaf number (37) and root length (181.75cm). The least values for all these characters were for Neostylis Lou Sneary. Duration from spike emergence to opening of florets was the maximum in Ascda Peggy Foo x Rhyn. Coelestis Blue and minimum in Neostylis Lou Sneary. Maximum spike longevity was recorded in V. Rothschildiana (29.30 days) whereas it was minimum in Rhy Sri Siam x Rhy gigantia (7.50 days). Interval of spike production was also the longest in Ascda. Peggy Foo x Rhyn. coelestis Blue and the minimum in Rhynchorides Bangkok Sunset. Spike production was the maximum in Neostylis Lou Sneary, followed by Ascda Srichai and Vasco Crownfox Red Gem. The varieties/ hybrids varied with regard to blooming period. The peak flowering was from May to July. Longer spike and rachis were noticed in Aerides quinque Vulnera Rhy. Coelestis. Vasco Blue Bay Pink had the highest number of florets/ spike and the shortest internodal length. Largest flowers were observed in V. Rothschildiana. Petal and labellum of the varieties also exhibited different colour patterns such as uniform, spotted, netted, tessellated and shaded. All the evaluated varieties were fragrant and were categorized based on different notes such as floral, fruity, spicy, green, sweet and miscellaneous. Fragrance was very faint in V. Rothschildiana whereas it was musty in Darwineria Cream Puff. With respect to the post-harvest characters longevity (vase life) was the maximum in V. JVB X Ascda Yip Sum Wah (17.30 days) and individual floret life (8.13 days) in V. Rothschildiana. Colour and pigmentation, texture, shape, pattern and size of florets as well as arrangement of florets on the spike were considered for the visual evaluation of a variety for use as cut flower. Considering the overall qualitative and quantitative attributes, Vascostylis Crownfox Red Gem, Vasco Blue Bay Blue, Rhynchorides Bangkok Sunset, V. Mimi Palmer, V. JVB X Ascda Yip Sum Wah and Vasco Blue Bay Pink were excellent for cut flower production. Plant quality evaluation was done based on fullness, growth and visual appearance, flower colour and pigmentation, spike longevity, shape and arrangement of foliage during the growth period. Fragrance scoring was also done based on intensity and diffusiveness, newness and beautifulness of fragrance. Based on the flowering phenology, four phenophases, namely, November – January, February – April, May – July and August – September were recorded and the varieties were categorized accordingly. Side-runs with different colour combinations were observed within a phenophase. The varieties were also categorized on the basis of flower colour, number of florets/ spike and floret size, longevity of spike on the plant , number of spikes produced / year and fragrance. Considering overall quantitative and qualitative characteristics, the evaluated varieties/ hybrids were categorized for cut flower, indoor and outdoor gardens for commercial exploitation as value added plants. The fragrance also makes it a novelty in landscaping to create a peaceful, relaxing environment.Item Morphological and cyto-molecular characterisation of Dendrobium Sw.cultivars(Department of Pomology and Floriculture,College of Agriculture, Vellayani, 2005) Krishnapriya, M; Sabina George, TThe research project “Morphological and cyto-molecular characterization of Dendrobium Sw. cultivars” was carried out at the Department of Pomology and Floriculture and the Department of Plant Biotechnology, College of Agriculture, Vellayani during 2003-2004. The objective of the study was to evaluate the growth and inflorescence production in Dendrobium varieties to carry out cyto-molecular characterization of Dendrobium varieties. Twelve varieties of Dendrobium of near flowering size plants were evaluated for their morphological and cyto-molecular characterization. The twelve Dendrobium varieties differed significantly for the morphological characters viz., shoot length, number of offshoots, shoot girth, leaf area, rate of shoot elongation, internodal length, flower colour, length of inflorescence, number of flowers per inflorescence, length of flower column and pedicel, thickness of inflorescence and leaf orientation. Significant varietal difference were observed among the twelve Dendrobium varieties for shoot length, shoot girth, internodal length of shoots, number of flowers, number of stomata on the adaxial and abaxial surface of the leaves, vase life, fresh and dry weight of inflorescence. High GCV and PCV were observed for shoot length, followed by leaf area, internodal length, length of inflorescence and number of flowers per inflorescence. The stomata on the surface of the leaf recorded ever highest GCV and PCV among all the characters. The shape of stomata ranged from oval shape to perfect round shape. Highest heritability values were recorded for number of stomata on the upper surface of the leaf. The genetic advance percentage was found highest for length of flowers column. In correlation studies, high positive phenotypic correlation was observed between number of flowers per inflorescence and length of inflorescence. The length of column had significant positive correlation with number of leaves, length of inflorescence, thickness of inflorescences and length of flower pedicel. Ranking of the varieties were done based on the value of selection indices. The variety V8 ranked first among the 12 Dendrobium varieties used in the experiment. The second and third ranks were gained by the varieties V4 and V1 respectively. The lowest rank i.e., the 12th rank was obtained by the variety V6. So from the selection index values, the variety V8 is the best one. DNA isolated from 12 varieties of Dendrobium was subjected to RAPD analysis. Among the 31 decamer primers, 24 yielded amplification products. By characterizing the 12 varieties of Dendrobium using morphological and cyto-molecular methods revealed that morphologically distinct and superior lines were genetically differentiable. Also the RAPD analysis gave a perfect differentiation of the varieties which is in line with morphological characterization.