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Subject: Agriculture × End date: 2008 × Start date: 2008 × Type: Thesis ×
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    ThesisItemOpen Access
    Enhancement of propagation efficiency in exotic varities of heliconia
    (Department of Pomology and Floriculture, College of Agriculture, Vellayani, 2008) Reshmi, C R; KAU; Sheela, V L
    Heliconias are among the most popular garden plants, both for the ease with which they can be grown and the sheer magnificence of the blooms. Studies were conducted to standardize rapid propagation techniques under in vitro and in vivo conditions. Three heliconia varieties belonging to three distinct groups viz., St. Vincent Red (small erect type), Golden Torch Adrian (hybrid) and Sexy Pink (large pendent type) were selected for the study. For in vitro culture establishment, shoot tip explants were effective. The treatment of shoot tips with 0.10 per cent mercuric chloride for ten minutes followed by dipping in 0.05 per cent mercuric chloride for five minutes (after trimming) resulted in better surface sterilization. Longitudinal cutting of the in vitro established shoot tip with apical dome into two halves and culturing them separately produced the highest number of axillary buds. Addition of 0.05 per cent activated charcoal to the establishment media reduced the media browning and hastened shoot initiation. For culture establishment of all the three varieties, MS medium supplemented with BA 5.00 mg l-1 was found to be the best. Murashige and Skoog medium supplemented with BA 2.00 mg l-1 resulted in the highest shoot proliferation in the variety St. Vincent Red. In Golden Torch Adrian, BA 2.00 mg l-1 + NAA 0.20 mg l-1 gave better results. In the variety Sexy Pink, Kinetin 5.00 mg l-1 + NAA 0.20 mg l-1 was the best. For further multiplication in Sexy Pink, BA 1.00 mg l-1 was sufficient. Solid culture medium was better for shoot proliferation in the variety Sexy Pink. Higher sucrose concentration (40.00 g l-1) increased the multiplication rate, but reduced the length of shoots as well as the number of leaves. Addition of activated charcoal to the media as well as exposure of cultures to light had negative effect on shoot proliferation. Full MS medium was found to be the best for in vitro rooting of the variety Sexy Pink. Addition of NAA 0.50 mg l-1 to the MS medium gave better results for in vitro rooting in Golden Torch Adrian and Sexy Pink. Sucrose @ 30.00 g l-1 was sufficient for in vitro rooting in the variety Sexy Pink. Activated charcoal delayed root initiation and reduced the number of roots in the variety Sexy Pink. Sand recorded 90.00 per cent survival in all the three varieties after two months of planting out. At varietal level, significant difference was evident in the total number of suckers. In the first experiment, the variety St. Vincent Red (3.82) was significantly superior in terms of total number of suckers. However, in the second experiment, St. Vincent Red (4.06) was on par with Golden Torch Adrian (4.10). The variety Sexy Pink produced comparatively taller suckers in both the trials. Varietal variation in the number of leaves was observed only in the earlier stages. During the preliminary field experiment, the variety Sexy Pink excelled in leaf area at almost all stages of observation. Among the three varieties, highest collar girth was recorded by suckers of Sexy Pink variety during the first two stages of observation. However, towards the later stages, it was statistically on par with St. Vincent Red. Foliar spray was superior to rhizome dip in terms of total number of suckers, height of suckers and the number of leaves. In the case of leaf area, both the treatments were more or less on par. Application of growth regulators had pronounced effect on sucker production at all the stages during the first experiment when BA 750 mg l-1 produced the highest number (4.19) of total suckers. In the second experiment, variation was evident only in the total number of suckers. Here, BA 850 mg l-1 produced the highest number (4.33) of suckers and it was on par with BA 700 mg l-1 (4.00) and GA3 650 mg l-1 (3.79). Irrespective of the stage of plant growth, gibberellic acid produced taller suckers and BA 500 mg l-1 resulted in the shortest suckers. BA treatments recorded comparatively higher number of leaves. Growth regulator application had remarkably influenced the leaf area of suckers also. Application of BA 1000 mg l-1 (3.53 cm) and GA3 800 mg l-1 (3.33 cm) recorded higher collar girth in suckers. VG interaction exerted significant variation in the number of suckers. At varietal level, BA 750 mg l-1 produced the highest number of suckers in St. Vincent Red (4.75), GA3 500 mg l-1 in Golden Torch Adrian (4.63) and GA3 750 mg l-1 in Sexy Pink (4.00). Among VG treatment combinations in the second experiment, the highest number of suckers (4.75) in the variety St. Vincent Red was produced by BA 700 mg l-1. The varieties Golden Torch Adrian (4.88) and Sexy Pink (3.75) recorded the highest with BA 850 mg l-1. Gibberellic acid produced taller suckers. In the second experiment, VG interaction had no significant effect on the height of suckers. Regarding the number of leaves, BA resulted in comparatively higher number of leaves in both the experiments. In all the three varieties, BA 850 mg l-1 produced the highest number of leaves. Collar girth was found to increase with increase in the concentrations of BA and GA3 in all the three varieties. The economics of foliar application of growth regulators revealed that BA 850 mg l-1 significantly enhanced the profit in the varieties Golden Torch Adrian and Sexy Pink. Although negligible, BA 700 mg l-1 recorded slight positive response in the variety St. Vincent Red with respect to profit.
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    ThesisItemOpen Access
    Performance of phalaenopsis orchids under varying shade levels
    (Department of Pomology and Floriculture, College of Agriculture, Vellayani, 2008) Pavithra, C G; KAU; Sabina George, T
    Orchids, the most beautiful flowers in god's creation, belongs to the family Orchidaceae. Phalaenopsis called the 'Moth Orchids' are recognised as the most beautiful flowers among orchids. Their long arching sprays of long lasting blooms are very popular throughout the world. One of the critical factors identified for successful growing of orchids is light. Determining the most suitable shade level for early vegetative growth of orchids is important as it influences the pre-flowering period, flower induction and flower production. The present work was thus taken up with a view to assess the performance of three Phalaenopsis cultivars under varying shade levels and to determine the most suitable shade level for early vegetative growth of hardened plants. The experiment was carried out at the Department of Pomology and Floriculture , College of Agriculture, Vellayani during 2006 -2007 with a view to assess the performance of Phalaenopsis orchids under varying shade levels and to determine the most suitable shade level for early vegetative growth of hardened plants. The following three commercially grown cultivars of Phalaenopsis orchids were used as the experimental material. The cultivars are Phalaenopsis Hsin, Phalaenopsis Luchia Pink and Phalaenopsis Brother Girl. For the three experiments, shade was provided with black high density polyethylene shade net calibrated for 25 %, 50 % and 75 % shade. Effect of shade and cultivar differences influenced the plant growth, shoot and leaf morphology and physiological and anatomical characteristics of the hardened plants. Among the cultivars, Phalaenopsis Hsin was found to be the best cultivar for obtaining greater number of roots, shoot length, shoot girth, internodal length, length and width of the leaves. Phalaenopsis Brother Girl was found to be the best cultivar for maximum leaf thickness and number of stomata on upper and lower surface of the leaves. Phalaenopsis Luchia Pink was found to be the best cultivar for greater root length and root thickness. The most suitable shade level conducive for shoot length, shoot girth, number of leaves, length and width of the leaves was found to be 50%. The most suitable shade level for greater number of roots, root thickness, thickness of leaves and chlorophyll (b) leaves was found to be 25% The interaction between shade and cultivar differences were also found to influence the performance of hardened plants.
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    ThesisItemOpen Access
    Reorienting the concept of agricultural development in the context of Kerala
    (College of Horticulture, Vellanikkara, 2008) Jaliya, M K; KAU; Joy, Mathew
    India’s agrarian culture and economy is in a progressive path of resurrection. The local administrative bodies are vested with increased powers to plan and execute need based development activities. Hence a clear understanding of the concept of agricultural development among the major stakeholders serves as a firm base for development. The present study entitled ‘Reorienting the concept of agricultural development in the context of Kerala’ was carried out in five blocks of Thrissur district, namely, Mullassery, Vadakkanchery, Chavakkad, Chowannur and Ollukkara. Progressive farmers, panchayat presidents, agricultural officers and agricultural scientists were the four groups of respondents selected for the study. An open ended question was formulated to explore, explain and clarify the perceptions of these respondent groups on the concept of agricultural development. The perception differences among the respondent groups were visually depicted by using the tool of concept mapping. It is a type of structured conceptualization that can be used by groups to develop a conceptual framework that can guide evaluation or planning. A ranking schedule with four sub-sections namely, physical dimension, economic dimension, ecological dimension and socio-psychological dimension was prepared after discussing with agricultural experts and incorporating productive suggestions from the different respondent groups. The Comparison of percentage mean scores between various respondent groups conducted after the analysis of the responses of open ended questions revealed that agricultural scientists scored the most (75 %) and farmers scored the least (36.3). The scores of agricultural officers and panchayat presidents were respectively 50 % and 41 %. The extent of perception differences among the four respondent groups regarding the concept of agricultural development was significant when it was compared with the standard definition chosen for the purpose of the present study. It was revealed from the study that the concept map of progressive farmers focused more on production related activities whereas concept map of panchayat presidents also followed suite except that it laid more importance on socio-concern. The concept map of agricultural officers was hinged on participatory approach and committed to social well-being of the society. The concept map of agricultural scientists stood out distinctly from the rest of the concept maps. The major emphasis was on marketing and finance assistance. A model for agricultural development was constructed from ten most preferred activity statements ranked by the four respondent groups among physical, economic, socio-psychological and ecological dimensions. A venn diagram was prepared as a pictoric representation of prioritised statements.