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Subject: Seed Science and Production Technology × Author: KAU × End date: 2020 × Start date: 2020 × Type: Thesis × Thesis Type: M.Sc ×
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    ThesisItemOpen Access
    Influence of storage structure on seed longevity in rice (Oryza sativa L.)
    (Department Seed Science and Technology, College of Horticulture, Vellanikkara, 2020) Jyothish Babu, E; KAU; Rose Mary, Francies
    Ageing of seeds is an inevitable natural deteriorative phenomenon, eventually resulting in loss of vigour and viability. Adopting appropriate storage, ensuring optimum storage environment have been advocated to slow down the pace of the deteriorative process during storage, maintain the seed quality and prolonging seed longevity. Considering the above, a study to elucidate the effect of different storage structure on seed longevity and quality of short duration rice varieties (Experiment 1) and medium rice varieties (Experiment 2) was conducted at College of Horticulture, Vellanikkara, Thrissur, during 2019 - 2020. The storage experiments were conducted following a completely randomized design with four varieties replicated thrice under five storage conditions (SC1 to SC5), each varying from the other with respect to the type of roofing and provision of ventilation. The short duration varieties used in Experiment 1 were Harsha, Matta Triveni, Manurathna and Kanchana, while, the medium durations varieties in Experiment 2 were, Aiswarya, Sreyas, Jyothi and Uma. The quality parameters of seeds stored in SC1 (Asbestos + ventilation), SC2 (Asbestos + without ventilation), SC3 (R.C.C. + ventilation), SC4 (R.C.C. + without ventilation) and SC5 (Asbestos + forced ventilation) were recorded at the start of storage and subsequently at monthly intervals for a period of nine months. The temperature and relative humidity in each storage condition were recorded at weekly intervals. Varieties, storage conditions, the period of storage and their interactions were found to exert significant influence on seed quality and longevity in both short duration and medium duration varieties. Irrespective of the varieties and the storage conditions, the seed quality parameters viz., germination (%), vigour indices (VI-I and VI-II) and field establishment (%), declined over the storage period, whereas an increase in seed moisture content (%), electrical conductivity of seed leachate (dSm-1) and seed microflora, was observed. Germination and longevity of varieties Matta Triveni and Harsha was higher than that of varieties Manurathna and Kanchana. Seed longevity was higher (8 months each) in varieties Harsha and Matta Triveni compared to varieties Manurathna and Kanchana (7 months each). The seed vigour indices (VI-I and VI-II), field establishment (%) of Matta Triveni were significantly high, while the estimates of seed moisture (%) and EC of seed leachate were significantly low in Kanchana. In case of medium duration varieties, although germination was higher in varieties Aiswarya and Shreyas compared to Jyothi and Uma, the longevity of seeds in all varieties was retained for eight months. Germination, vigour (VI-II) and field establishment (%) was significantly high in Aiswarya, while the seed moisture and EC of seed leachate was found to be significantly low in Sreyas. Variety Uma registered significant low seed quality parameters. In both short and medium duration varieties, the quality of seeds stored under ventilated conditions (SC1, SC3 and SC5) was found to be the significantly superior to those stored in non-ventilated structures (SC2 and SC4). Irrespective of the type of roofing (Asbestos or R.C.C), seed longevity in ventilated godowns were found to be retained above IMSCS, one month longer (8 MAS) than when stored under nonventilated environment (7 MAS). The interaction between varieties, storage condition and the period of storage, indicated that seed longevity in all medium duration varieties stored under ventilated storage and non-ventilated storages was eight and seven months respectively. Unlike in the medium duration group, the longevity of all the longevity of short duration varieties Matta Triveni and Harsha was higher by a period one month i.e., 8 MAS, when stored under ventilated environments conditions viz., R.C.C. + ventilation (SC3), Asbestos + ventilation (SC1) and Asbestos + forced ventilation (SC5) as against 7 MAS under non-ventilated storage [Asbestos + without ventilation (SC2), R.C.C. + without ventilation (SC4)] High temperature and relative humidity within the storage environment strongly influenced germination and seed longevity. The decline in germination was found to be more pronounced when the seed was exposed to high temperatures in the early period of storage i.e., between 1 and 13th week, while high RH during the 2nd half of the storage period (i.e., between 24th and 36th week), proved to be detrimental to seed longevity. Among the storage structures, the temperature and RH inside ventilated storage (SC3, SC1 and SC5) was relatively lower than that in non-ventilated structure (SC4 and SC4). Marginal variations in temperature and RH was evident between the ventilated stores, with the least estimate in Asbestos + forced ventilation (SC5). However, most quality parameters and longevity of seeds in these conditions were on par with each other. From the above results, it can be summarized that storing seeds in ventilated storage structures, was clearly advantageous over storing them under non-ventilated conditions. Only marginal variations in seed quality parameters was observed between the ventilated conditions. Neither did storing seed in godowns with provision for forced ventilation improve the longevity of stored seeds over those with provision for natural ventilation. Incurring additional expenditure on installation, maintenance and operation of forced ventilation system did not to confer any additional benefits. Considering all the above, it would be more advantageous to store seeds under ventilated conditions with provision for natural ventilation.
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    ThesisItemOpen Access
    Influence of storage structure on seed longevity in rice (Oryza sativa L.)
    (Department Seed Science and Technology, College of Horticulture, Vellanikkara, 2020) Jyothish Babu, E; KAU; Rose Mary, Francies
    Ageing of seeds is an inevitable natural deteriorative phenomenon, eventually resulting in loss of vigour and viability. Adopting appropriate storage, ensuring optimum storage environment have been advocated to slow down the pace of the deteriorative process during storage, maintain the seed quality and prolonging seed longevity. Considering the above, a study to elucidate the effect of different storage structure on seed longevity and quality of short duration rice varieties (Experiment 1) and medium rice varieties (Experiment 2) was conducted at College of Horticulture, Vellanikkara, Thrissur, during 2019 - 2020. The storage experiments were conducted following a completely randomized design with four varieties replicated thrice under five storage conditions (SC1 to SC5), each varying from the other with respect to the type of roofing and provision of ventilation. The short duration varieties used in Experiment 1 were Harsha, Matta Triveni, Manurathna and Kanchana, while, the medium durations varieties in Experiment 2 were, Aiswarya, Sreyas, Jyothi and Uma. The quality parameters of seeds stored in SC1 (Asbestos + ventilation), SC2 (Asbestos + without ventilation), SC3 (R.C.C. + ventilation), SC4 (R.C.C. + without ventilation) and SC5 (Asbestos + forced ventilation) were recorded at the start of storage and subsequently at monthly intervals for a period of nine months. The temperature and relative humidity in each storage condition were recorded at weekly intervals. Varieties, storage conditions, the period of storage and their interactions were found to exert significant influence on seed quality and longevity in both short duration and medium duration varieties. Irrespective of the varieties and the storage conditions, the seed quality parameters viz., germination (%), vigour indices (VI-I and VI-II) and field establishment (%), declined over the storage period, whereas an increase in seed moisture content (%), electrical conductivity of seed leachate (dSm-1) and seed microflora, was observed. Germination and longevity of varieties Matta Triveni and Harsha was higher than that of varieties Manurathna and Kanchana. Seed longevity was higher (8 months each) in varieties Harsha and Matta Triveni compared to varieties Manurathna and Kanchana (7 months each). The seed vigour indices (VI-I and VI-II), field establishment (%) of Matta Triveni were significantly high, while the estimates of seed moisture (%) and EC of seed leachate were significantly low in Kanchana. In case of medium duration varieties, although germination was higher in varieties Aiswarya and Shreyas compared to Jyothi and Uma, the longevity of seeds in all varieties was retained for eight months. Germination, vigour (VI-II) and field establishment (%) was significantly high in Aiswarya, while the seed moisture and EC of seed leachate was found to be significantly low in Sreyas. Variety Uma registered significant low seed quality parameters. In both short and medium duration varieties, the quality of seeds stored under ventilated conditions (SC1, SC3 and SC5) was found to be the significantly superior to those stored in non-ventilated structures (SC2 and SC4). Irrespective of the type of roofing (Asbestos or R.C.C), seed longevity in ventilated godowns were found to be retained above IMSCS, one month longer (8 MAS) than when stored under nonventilated environment (7 MAS). The interaction between varieties, storage condition and the period of storage, indicated that seed longevity in all medium duration varieties stored under ventilated storage and non-ventilated storages was eight and seven months respectively. Unlike in the medium duration group, the longevity of all the longevity of short duration varieties Matta Triveni and Harsha was higher by a period one month i.e., 8 MAS, when stored under ventilated environments conditions viz., R.C.C. + ventilation (SC3), Asbestos + ventilation (SC1) and Asbestos + forced ventilation (SC5) as against 7 MAS under non-ventilated storage [Asbestos + without ventilation (SC2), R.C.C. + without ventilation (SC4)] High temperature and relative humidity within the storage environment strongly influenced germination and seed longevity. The decline in germination was found to be more pronounced when the seed was exposed to high temperatures in the early period of storage i.e., between 1 and 13th week, while high RH during the 2nd half of the storage period (i.e., between 24th and 36th week), proved to be detrimental to seed longevity. Among the storage structures, the temperature and RH inside ventilated storage (SC3, SC1 and SC5) was relatively lower than that in non-ventilated structure (SC4 and SC4). Marginal variations in temperature and RH was evident between the ventilated stores, with the least estimate in Asbestos + forced ventilation (SC5). However, most quality parameters and longevity of seeds in these conditions were on par with each other. From the above results, it can be summarized that storing seeds in ventilated storage structures, was clearly advantageous over storing them under non-ventilated conditions. Only marginal variations in seed quality parameters was observed between the ventilated conditions. Neither did storing seed in godowns with provision for forced ventilation improve the longevity of stored seeds over those with provision for natural ventilation. Incurring additional expenditure on installation, maintenance and operation of forced ventilation system did not to confer any additional benefits. Considering all the above, it would be more advantageous to store seeds under ventilated conditions with provision for natural ventilation.
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    ThesisItemOpen Access
    Impact of seed protectants on seed longevity and storage pests in rice (Oryza sativa L.)
    (Department of Seed Science and Technology, College of Horticulture, Vellanikkara, 2020) Hariprasad, K; KAU; Rose Mary Francies
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    ThesisItemOpen Access
    Seed invigoration with nanoparcticles for seed yield and quality in chilli (Capsicum annuum L.)
    (Department of Seed Science and Technology, College of Horticulture, Vellanikkara, 2020) Riya Mary, Mathew.; KAU; Dijee, Bastian
    The study “Seed invigoration with nanoparticles for seed yield and quality in chilli” was conducted in the Department of Seed Science and Technology, College of Horticulture, Vellanikkara during May 2019 with the objective of standardizing the optimum seed treatment dose required for increasing yield, improving quality and prolonging seed longevity. Normal grade and nano grade zinc oxide (ZnO) and titanium dioxide (TiO2) were used for seed treatment on chilli variety Anugraha. The study consisted of two experiments. In the first experiment, chilli seeds dry dressed with 500, 900 and 1300 mg kg-1 of normal and nano grade ZnO and TiO2 along with control (thirteen treatments) were raised in a Randomized block design with three replications. While all treated seeds performed better than control (untreated seeds) treatments with nanoparticles performed better than the normal grade particles. Highly significant variations was observed for traits such as plant spread, plant height, days to harvest, fruit length, number of fruits per plant, fruit weight at maturity, fruit yield, number of seeds per fruit, seed yield per plant and 100 seed weight. Seed treatments with nano ZnO @ 1300 mg kg-1 of seed (T4) performed superior for plant spread (60.1 cm), plant height (67.30 cm), number of fruits per plant (122), fruit length (7.40cm), fruit weight (3.46g), fruit yield (422.70 g) and seed yield per plant (41.14 g). Normal grade ZnO treatments was effective in improving number of seeds per fruit (62) (ZnO @ 900 mg kg-1 of seed). Significant effects were recorded when seeds were treated with normal grade TiO2 @ 500 mg kg-1 of seed (T11) for fruit weight at maturity (3.53 g). In the second experiment the effect of wet seed treatment with nanoparticles on seed storability was assessed. The experiment was laid out in Completely Randomized Design with thirteen treatments in three replications. Treatments include nano ZnO and TiO2 at 100,250,500 and 100 mg kg-1. Seed quality parameters like germination, seedling length, dry weight and vigour indices showed a declining trend throughout the storage period while electrical conductivity and seed infection increased. Treatments ZnO@100 mg kg-1 of seed (T2), ZnO@250 mg kg-1 of seed (T3 ), ZnO@500 mg kg-1 of seed (T4 ), ZnO@1000 mg kg-1 of seed (T6), TiO2@500 mg kg-1 of seed (T10), TiO2@750 mg kg-1 of seed (T11) and TiO2@1000 mg kg-1 of seed (T12) retained germination above 60 % (IMSCS) at the end of seven months of storage. ZnO @ 250 mg kg-1 of seed (T3) retained the highest germination per cent of 65.66 %. Vigour index-I was found to be high in ZnO @ 1000mg kg-1 of seeds (T6) (925.88) and vigour index II in TiO2 @1000 mg kg-1 of seed (T12) (1471.81) at the end of storage.The electrical conductivity of seed leachate obtained from nano ZnO @ 250 mg kg-1 of seed and nano TiO2 @ 750 mg kg-1 of seed recorded the lowest values (295μScm-1and 290.33 μScm-1).Pathogen infection in seeds were found to be lower in treated seeds than in untreated control. Infection was recorded in nano ZnO @ 100 mg kg-1 of seeds (T2) (13.3%) and nano TiO2 @ 250 mg kg-1 of seeds (T9) (10%) treatments. The seed storage fungi observed were Aspergillus niger and Aspergillus flavus. Seed treatments with inorganic nanoparticles are effective in improving field performance and as well as retaining seed quality in storage. Nano ZnO at 1300 mg kg-1 of seeds was the best treatment followed by nano TiO2 at 900mg kg-1 of seeds in improving yield in chilli. Treatments nano ZnO at 250 and 1000 mg kg-1 of seed may be used as seed treatments to enhance seed longevity in chilli.