1. KAUTIR (Kerala Agricultural University Theses Information and Retrieval)
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Item Varietal evaluation of guava(Psidium guajava L.) for urban horticulture(Department of Fruit Science, College of Agriculture, Vellayani, 2025) Swetha, V; Simi, SThe present research work entitled “Varietal evaluation of guava (Psidium guajava L.) for urban horticulture” was conducted at the Department of Fruit Science, College of Agriculture, Vellayani, from 2023 November to 2024 October. The study was under taken to evaluate the growth and yield response of planting materials of guava to different type and size of containers and to evaluate the growth response of different varieties of guava in containers. The experiment 1 entitled “Performance evaluation of guava (Psidium guajava L.) in containers” was laid out in Completely Randomized Design (CRD) with 18 treatments and 3 replications using the guava variety Arka Kiran. The treatments included two container types (C1 - Plastic container and C2 - Air-pot), three container sizes (V1 – 40 L, V2 – 60 L and V3 – 80 L) and three different planting materials (P1 - Air layers, P2 - Rooted cuttings and P3 - Grafts). The medium of planting consisted of soil, coir pith and farm yard manure in 1 : 1 : 1 ratio across all treatment. Twelve- month-old potted plants were subjected to the study. Plants in plastic containers (C1), registered significantly taller growth with greater plant spread, primary stem girth, number of leaves per plant (at 15, 18, and 21 MAP), stem girth (at 15 and 18 MAP), root dry weight, shoot dry weight, and leaf area (at 21 MAP) compared to those in airpots. Meanwhile, plants in airpots exhibited earlier flowering, shorter duration from flowering to harvest and longer flowering duration. They also produced greater number of fruits and higher fruit weight, length, diameter and fruit yield. Among different container volumes, 80 L (V3) had the tallest plants with the highest plant spread, stem girth and primary stem girth and the highest number of leaves per plant (15 MAP, 18 MAP and 21 MAP). In addition, they exhibited earliness in flowering and harvest, highest flowering duration, fruit weight, length, diameter, number of fruits and fruit yield. Root dry weight, shoot dry weight (21 MAP) and leaf area were also the highest in V3. 168 Among the different planting materials, air layers produced taller plants with greater plant spread (at 15, 18, and 21 MAP), number of leaves per plant, leaf area and root-to-shoot ratio (at 21 MAP). In addition, they exhibited early flowering, longest flowering duration and the shortest number of days from flowering to harvest. The number of fruits, fruit weight, fruit length, diameter and fruit yield were also observed to be the highest in air layers. Grafts (P3) recorded the highest values for stem girth, primary branch girth, root dry weight and shoot dry weight. The fruits were analysed for quality parameters, including TSS, total sugar, reducing sugar, ascorbic acid, total antioxidant activity and total carotenoids. Container size, type, and planting material showed a significant difference in ascorbic acid and carotenoid content, whereas all other parameters were non-significant. Ascorbic acid and carotenoid content were higher in airpots. In terms of container volume, the 80 L containers showed higher ascorbic acid(227.67 mg 100g-1) and carotenoid levels (0.67 mg 100g-1) , while, among planting materials, air-layered plants had the highest values. Leaf tissue was analysed for physiological and biochemical parameters viz., chlorophyll content, total carotenoids, total reducing sugars and total soluble proteins at 18 MAP. Container type and planting material did not show any significant effect on these parameters, while 80 L container volume showed significantly higher total soluble proteins compared to 40 and 60 litres. The two factor interaction between container type and size (C x V), showed that 80 L plastic containers (C1V3) recorded significantly higher plant spread (E-W and N-S), stem girth, leaves per plant, leaf area and root dry weight. The shoot dry weight was higher in both plastic container and air-pots with 80 L (C1V3 and C2V3). Air-pots with 80 L (C2V3), exhibited early flowering with more fruits per plant, enhanced flowering duration, earlier flowering to harvest and the highest fruit weight, length, diameter and fruit yield. Interaction between container type and planting material (C x P) also confirms similar results in air-pots with air layers (C2P1). Root : shoot ratio was the highest in air-pots with grafted plants (C2P3). The two factor interaction between container size and planting material (V x P) showed that air layers grown in 80 L containers (V3P1) outperformed other combinations with respect to plant height, plant 169 spread, leaves per plant, leaf area, number of fruits, flowering duration, days to flowering, days from flowering to harvest, fruit weight, length, diameter and fruit yield. Shoot dry weight, stem girth and primary stem girth were the highest in 80 L with graft (V3P3). In three factor interaction, 80 L plastic containers with graft (C1V3P3) showed higher root dry weight and shoot dry weight while plant height and leaf area were the highest for air layers in 80 L plastic container (C1V3P1). The least number of days to flowering and days from flowering to harvest were observed in 80 L airpots with air layers (C2V3P1) they also produced the highest number of leaves and fruits, as well as the greatest fruit weight, length, diameter and fruit yield. Another notable feature observed in the study is the presence of root coiling in plastic containers of all sizes (40, 60, and 80 L), regardless of the type of planting material. In contrast, root coiling was absent in airpots of all container sizes. This study underscores the importance of selecting appropriate container types, sizes, and planting materials for successful guava cultivation in containers. Airpots outperformed plastic containers by enhancing reproductive traits like early flowering, extended flowering duration, and superior fruit yield and quality. Larger containers (80 L) showed the best results across growth, fruit yield and biochemical parameters, including ascorbic acid and carotenoids. Among planting materials, air layers excelled in vegetative growth, earliness in flowering, and fruit quality, establishing 80 L airpots with air layers as the optimal choice for container-based guava cultivation. The experiment 2 entitled “Varietal evaluation of guava (Psidium guajava L.) for urban horticulture” was laid out in Completely Randomized Design (CRD) with 5 treatments and 3 replications. The treatments included five varieties of air layered guava: T1-Allahabad Safeda, T2-Lucknow 49, T3-Arka Kiran, T4-Arka Rashmi and T5- Arka Mridula. (Note: The best container type, container size and planting material (Airpots 80 L air layers) was selected from the result of first year observations of the experiment entitled “Performance evaluation of guava (Psidium guajava L.) in container and used in this experiment). T5-Arka Mridula registered the highest plant 170 height, primary and the secondary stem girth, while early flowering with highest number of flowers was registered in T4-Arka Rashmi. Leaf tissue was analysed for physiological and biochemical parameters viz., chlorophyll content, total carotenoids, total reducing sugars and total soluble proteins at 6 MAP. Total chlorophyll (0.98 mg 100 g -1), reducing sugar (1.84%) and carotenoid content(0.70 mg 100 g -1) were the highest in T5-Arka Mridula and total soluble protein was the highest in T1-Allahabad Safeda. This study emphases the importance of the growth response of different varieties of guava in containers. Among vegetative parameters, plant height, primary and secondary stem girth were the highest in Arka Mridula which was reflected in physiological and biochemical parameters like chlorophyll, reducing sugar and carotenoid contents that gave the highest values. However, in plant spread and flowering parameters like days to flowering and number of flowers the highest values were in Arka Rashmi. Plants with a compact canopy and good reproductive parameters are ideal for container growing. Thus, the present study unveils the suitability of Arka Rashmi for container growing of guava.Item Varietal evaluation of guava(Psidium guajava L.) for urban horticulture(Department of Fruit Science, College of Agriculture, Vellayani, 2025) Swetha, VThe present research work entitled “Varietal evaluation of guava (Psidium guajava L.) for urban horticulture” was conducted at the Department of Fruit Science, College of Agriculture, Vellayani, from 2023 November to 2024 October. The study was under taken to evaluate the growth and yield response of planting materials of guava to different type and size of containers and to evaluate the growth response of different varieties of guava in containers. The experiment 1 entitled “Performance evaluation of guava (Psidium guajava L.) in containers” was laid out in Completely Randomized Design (CRD) with 18 treatments and 3 replications using the guava variety Arka Kiran. The treatments included two container types (C1 - Plastic container and C2 - Air-pot), three container sizes (V1 – 40 L, V2 – 60 L and V3 – 80 L) and three different planting materials (P1 - Air layers, P2 - Rooted cuttings and P3 - Grafts). The medium of planting consisted of soil, coir pith and farm yard manure in 1 : 1 : 1 ratio across all treatment. Twelve- month-old potted plants were subjected to the study. Plants in plastic containers (C1), registered significantly taller growth with greater plant spread, primary stem girth, number of leaves per plant (at 15, 18, and 21 MAP), stem girth (at 15 and 18 MAP), root dry weight, shoot dry weight, and leaf area (at 21 MAP) compared to those in airpots. Meanwhile, plants in airpots exhibited earlier flowering, shorter duration from flowering to harvest and longer flowering duration. They also produced greater number of fruits and higher fruit weight, length, diameter and fruit yield. Among different container volumes, 80 L (V3) had the tallest plants with the highest plant spread, stem girth and primary stem girth and the highest number of leaves per plant (15 MAP, 18 MAP and 21 MAP). In addition, they exhibited earliness in flowering and harvest, highest flowering duration, fruit weight, length, diameter, number of fruits and fruit yield. Root dry weight, shoot dry weight (21 MAP) and leaf area were also the highest in V3. 168 Among the different planting materials, air layers produced taller plants with greater plant spread (at 15, 18, and 21 MAP), number of leaves per plant, leaf area and root-to-shoot ratio (at 21 MAP). In addition, they exhibited early flowering, longest flowering duration and the shortest number of days from flowering to harvest. The number of fruits, fruit weight, fruit length, diameter and fruit yield were also observed to be the highest in air layers. Grafts (P3) recorded the highest values for stem girth, primary branch girth, root dry weight and shoot dry weight. The fruits were analysed for quality parameters, including TSS, total sugar, reducing sugar, ascorbic acid, total antioxidant activity and total carotenoids. Container size, type, and planting material showed a significant difference in ascorbic acid and carotenoid content, whereas all other parameters were non-significant. Ascorbic acid and carotenoid content were higher in airpots. In terms of container volume, the 80 L containers showed higher ascorbic acid(227.67 mg 100g-1) and carotenoid levels (0.67 mg 100g-1) , while, among planting materials, air-layered plants had the highest values. Leaf tissue was analysed for physiological and biochemical parameters viz., chlorophyll content, total carotenoids, total reducing sugars and total soluble proteins at 18 MAP. Container type and planting material did not show any significant effect on these parameters, while 80 L container volume showed significantly higher total soluble proteins compared to 40 and 60 litres. The two factor interaction between container type and size (C x V), showed that 80 L plastic containers (C1V3) recorded significantly higher plant spread (E-W and N-S), stem girth, leaves per plant, leaf area and root dry weight. The shoot dry weight was higher in both plastic container and air-pots with 80 L (C1V3 and C2V3). Air-pots with 80 L (C2V3), exhibited early flowering with more fruits per plant, enhanced flowering duration, earlier flowering to harvest and the highest fruit weight, length, diameter and fruit yield. Interaction between container type and planting material (C x P) also confirms similar results in air-pots with air layers (C2P1). Root : shoot ratio was the highest in air-pots with grafted plants (C2P3). The two factor interaction between container size and planting material (V x P) showed that air layers grown in 80 L containers (V3P1) outperformed other combinations with respect to plant height, plant 169 spread, leaves per plant, leaf area, number of fruits, flowering duration, days to flowering, days from flowering to harvest, fruit weight, length, diameter and fruit yield. Shoot dry weight, stem girth and primary stem girth were the highest in 80 L with graft (V3P3). In three factor interaction, 80 L plastic containers with graft (C1V3P3) showed higher root dry weight and shoot dry weight while plant height and leaf area were the highest for air layers in 80 L plastic container (C1V3P1). The least number of days to flowering and days from flowering to harvest were observed in 80 L airpots with air layers (C2V3P1) they also produced the highest number of leaves and fruits, as well as the greatest fruit weight, length, diameter and fruit yield. Another notable feature observed in the study is the presence of root coiling in plastic containers of all sizes (40, 60, and 80 L), regardless of the type of planting material. In contrast, root coiling was absent in airpots of all container sizes. This study underscores the importance of selecting appropriate container types, sizes, and planting materials for successful guava cultivation in containers. Airpots outperformed plastic containers by enhancing reproductive traits like early flowering, extended flowering duration, and superior fruit yield and quality. Larger containers (80 L) showed the best results across growth, fruit yield and biochemical parameters, including ascorbic acid and carotenoids. Among planting materials, air layers excelled in vegetative growth, earliness in flowering, and fruit quality, establishing 80 L airpots with air layers as the optimal choice for container-based guava cultivation. The experiment 2 entitled “Varietal evaluation of guava (Psidium guajava L.) for urban horticulture” was laid out in Completely Randomized Design (CRD) with 5 treatments and 3 replications. The treatments included five varieties of air layered guava: T1-Allahabad Safeda, T2-Lucknow 49, T3-Arka Kiran, T4-Arka Rashmi and T5- Arka Mridula. (Note: The best container type, container size and planting material (Airpots 80 L air layers) was selected from the result of first year observations of the experiment entitled “Performance evaluation of guava (Psidium guajava L.) in container and used in this experiment). T5-Arka Mridula registered the highest plant 170 height, primary and the secondary stem girth, while early flowering with highest number of flowers was registered in T4-Arka Rashmi. Leaf tissue was analysed for physiological and biochemical parameters viz., chlorophyll content, total carotenoids, total reducing sugars and total soluble proteins at 6 MAP. Total chlorophyll (0.98 mg 100 g -1), reducing sugar (1.84%) and carotenoid content(0.70 mg 100 g -1) were the highest in T5-Arka Mridula and total soluble protein was the highest in T1-Allahabad Safeda. This study emphases the importance of the growth response of different varieties of guava in containers. Among vegetative parameters, plant height, primary and secondary stem girth were the highest in Arka Mridula which was reflected in physiological and biochemical parameters like chlorophyll, reducing sugar and carotenoid contents that gave the highest values. However, in plant spread and flowering parameters like days to flowering and number of flowers the highest values were in Arka Rashmi. Plants with a compact canopy and good reproductive parameters are ideal for container growing. Thus, the present study unveils the suitability of Arka Rashmi for container growing of guava.Item Fertigation scheduling for vegetable cowpea (Vigna unguiculata ssp. sesquipedalis) under naturally ventilated polyhouse(Department of Vegetable science, College of Agriculture,Vellanikkara, 2024) Sai Lakshmi Mithila, U.Vegetable cowpea stands out as a highly valued crop in Kerala, commanding lucrative prices due to its versatility and significant nutritional advantages for human health. The cultivation of this crop proves to be financially rewarding when meticulous inputs are provided. Precision farming offers a method to precisely apply fertilizers, and the primary objective of this study is to establish a standard fertilizer recommendation for applying fertilizers in a precise manner. Vegetable cowpea exists in three distinct types: bush cowpea, trailing, and semi-trailing. These varieties exhibit significant differences in growth habits, spacing requirements, yields, biomass, and cultural practices. Consequently, a standardized fertigation schedule can be proposed, taking into account the distinct characteristics of bush and trailing cultivars of cowpea. The Kerala Agricultural University (KAU) has an ad hoc recommendation for precision farming in yard-long beans (170:105:310 kg N: P: K/ha). This study focused on standardising fertigation schedule and evaluating the effects of various fertigation levels on a bush-type cultivar, Kashi Kanchan, and a trailing-type variety, KAU Deepika. Fertigation involves delivering water-soluble fertilizers through irrigation water, offering a more superior nutrient and water use efficiency compared to traditional methods of fertilizer application. The research was conducted at the Department of Vegetable Science, College of Agriculture, Vellanikkara, from November to January 2024. The first experiment, focusing on fertigation scheduling for yard-long bean cv. Deepika, employed a randomized block design featuring seven fertigation levels: 50% RDF, 60% RDF, 70% RDF, 80% RDF, 90% RDF, 100% RDF, and 110% RDF. The second experiment (fertigation scheduling for vegetable cowpea cv. Kashi Kanchan), also utilized a randomized block design with seven fertigation levels: 40% RDF, 50% RDF, 60% RDF, 70% RDF, 80% RDF, 90% RDF, and 100% RDF. Fertigation was administered at three-day intervals, and Trichoderma-enriched farmyard manure (FYM) was uniformly applied at a rate of 15 t/ha across all treatments. In all the treatments, basal application of phosphorus was given. Hundred percent recommended dose of fertilizers was 170:105:310 kg N: P: K/ha (40 splits). In the present study, only 21 splits of fertilizers were applied because the crop ended early, 70 days after sowing due to high temperature, phytotoxicity and sucking pest infestation. The actual quantity of fertilizer (21 splits) applied was at the rate of 89.25:80.09:162.75 kg N: P: K/ha (100% RDF). Findings of the first experiment in yard long bean cv. Deepika revealed that fertigation had significant effect on internodal length, number of pods per plant and yield. 110% RDF registered maximum internodal length (34.53 cm), maximum number of pods per plant (19.97). Highest yield per plant (0.55 kg) was recorded in 110% RDF and it was statistically on par with 100% RDF (0.53 kg). Fertigation had significant effect on average pod length and weight. Pod girth did not show any marked difference with different levels of fertigation. In KAU Deepika, highest average pod length (62.63 cm) was recorded in 110% RDF which was statistically on par with 100% RDF (61.80 cm) and highest average pod weight (27.60 g) was noticed in 110% RDF and it was statistically on par with 100% RDF (27.37 g) and 90% RDF (27.37 g). Fertigation had no significant effect on number of flowers per cluster, pod colour, crude fiber and trypsin inhibitor content of the pods. Days to first flower opening, days to first harvest and number of harvests were significantly influenced with fertigation doses. Treatment seven (110% RDF) took lower days to first flower opening (40.2 DAS) and days to first harvest (51.20 DAS) and it was statistically on par with T6 and T5. Maximum number of harvests were recorded in 110% RDF (6.67) which was statistically on par with 100% RDF, 90% RDF, 80% RDF and 70% RDF. Water content was highest in the pods of 100% RDF (91.10%) and it was statistically on par with 110% RDF (91.02%). T6 showed less Physiological loss in weight (15.35%) and it was statistically on par with 110% RDF (15.76%). Benefit-cost ratio was found to be highest for 110% RDF (1.52) and the second highest B:C ratio was obtained for 100% RDF (1.49). Findings of the second experiment in Kashi Kanchan revealed that 100% RDF registered maximum internodal length (23.47 cm). Maximum number of pods per plant (26.18) and highest yield per plant (0.25 kg) was recorded in 100% RDF and it was statistically on par with 90% RDF. Maximum average pod length (31.80 cm) and average pod weight (9.60 g) were observed for 100% RDF which was statistically on par with 90% RDF. Average pod girth, number of flowers per cluster, days to first flower opening, days to first harvest, number of harvests, crude fiber, trypsin inhibitor and colour of the pod were not influenced by nutrition level. T7 (100% RDF) registered maximum water content (89.66%) and less physiological loss in weight (16.18%) and it was statistically on par with 90% RDF. Benefit-cost ratio was found to be highest for 100% RDF (1.18) and the second highest B:C ratio was obtained for 90% RDF (1.15). Incidence of pests like cut worm, leaf miner, whitefly, thrips, mites, aphids were observed during the study. The crop was affected by diseases such as powdery mildew, alternaria leaf spot and cercospora leaf spot. Thus, based on the present study it can be concluded that 110% RDF (98.18:88.1:179.03 kg N: P: K/ha) for yard long bean cv. Deepika and 100% RDF (89.25:80.09:162.75 kg N: P: K/ha) for vegetable cowpea cv. Kashi Kanchan is the best fertigation dosage for obtaining maximum yield and B:C ratio grown inside polyhouse.Item Evaluation and utilization of plant pigments as natuaral food colourants(Department of postharvest management,College of Agriculture,Vellanikkara, 2023) NETRAVATI; Saji GomezItem 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 Studies on growth and bearing habits of certain varieties of bhendi (Abelmoschus esculentus (L.) Moench.)with special reference to fruit maturity and quality(Regional post-graduate training centre, Agricultural college and research institute, Coimbatore., 1964) Ravindra, KItem Morphological studies and quality evaluation of ginger (zingiber officinale rosco) types(Department of Horticulture (Plantation Crops), College of Horticulture, Vellanikkara, 1978) Nybe, E V; Sivaraman Nair, P CA detailed study of 25 ginger types was conducted during the period from April 1977 to June 1978 at the College of Horticulture, Vellanikkara with a view to find out the feasibility of fixing up specific morphological characters to identify different types, to screen out ginger types with high yield, high quality and resistant or tolerant to pests and diseases and to study the quality variations at different periods of maturity. The study revealed that morphological characters are not reliable to classify the ginger types, although some of them can be identified by rhizome characters. The morphological characters such as length of leaf, leaf area index and number, length and girth of primary and secondary fingers were found to be positively correlated with yield. All the types studied are susceptible to the incidence of soft-rot, leaf –spot and shoot-borer. The type Maran was relatively tolerant to soft-rot whereas Rio-de-Janeiro was found to be the most susceptible type. Yield was found to vary significantly among the types studied. Maximum yield was recorded in Nadia followed by Bajpai, Maran and Narasapattom. Maximum oleoresin percentage was in Rio-de-Janeiro and highest percentage of oil recovery in Karakal. But the maximum yield per hectare of oleoresin and oil was in the type Maran. Fibre content was minimum in China and maximum in Kuruppampady closely followed by Maran. The yield, dryage and percentage of oleoresin, oil and crude fibre varied significantly among the different maturity periods studied. The percentage of oleoresin, oil and fibre was maximum at 165 days after planting. But the maximum yield per hectare of oleoresin and oil were found at 270, 195, 225 and 225 days after planting in Rio-de-Janeiro, Maran, Kuruppampady and Wynad Local respectively. Cultivation of the types Nadia, Bajpai and Maran is recommended for higher total yield of dry ginger for the plains of Kerala. Considering the low incidence of soft – rot and higher yield of oleoresin and ginger oil the type Maran is preferred.Item Evaluation of Nendran (Musa AAB Group) Ecotypes(Department of Horticulture, College of Agriculture, Vellayani, 1996) Bindu Viveka Devi; Jayachandran Nair, C SThe investigation "Evaluation of 'Nendran' (Musa AAB group) ecotypes" was conducted at the Department of Horticulture, College of Agriculture, V e l l a y a n i , Thiruvananthapuram during 1994-'95 inorder to study the effect of ecotype variation on growth, yield and fruit quality of 'Nendran' banana. The results obtained are presented below : Vegetative characters like plant height, girth at later stages, number of leaves per plant, phylacron at early stages, leaf longevity, leaf area duration, leaf area index at later stages and monthly growth rate at early stages showed variation among the different ecotypes. The number of suckers per plant were almost uniform for all the ecotypes. The time taken for flowering and total crop duration varied with ecotypes but the maturity period of the bunches was uniform for all the ecotypes. Eventhough bunch yield was maximum in Kaliethan, the number of hands and fingers per bunch were the lowest in this type. Fruit characters like finger length, finger weight, peel weight and pulp weight were high in Kaliethan where as the pulp/peel ratio was high in Poovanchira. Chengazhikodan and Kothala were superior in fruit quality compared to Kaliethan. The leaf nutrient status at flowering stage varied only in the case of potassium where as both phosphorus and potassium varied at harvest stage. Poovanchira, Puthur and Kothala types had higher levels of NPK at flowering time though Chengazhikodan had the highest potassium content. During harvest stage, Kothala and Chengazhikodan had higher NPK content compared to others types. The dry matter production was higher in Kaliethan and Pandaloor in both vegetative part and fruits. The extent of sigatoka leaf spot did not differ significantly among the 'Nendran' ecotypes during the different stages of growth. There was no incidence of bunchy top in any of the treatment plants. Nematode infestation in root was low in Poovanchira, Kaliethan and Chengazhikodan and high in Muttathukonam and Kothala types where as the rhizome weevil incidence was low in Puthur, Kothala and Kaliethan an 1 high in Chengazhikodan and Pandaloor types. Correlation and path analysis studies in 'Nendran' ecotypes indicated that leaf area duration (LAD), girth • fingers, time taken for flowering, number of fingers re bunch, plant height at post floral initiation stage and g i r t h of plant at floral initiation stage had a p o s i t i v correlation with bunch weight. So these characters can 1 -? considered for selecting superior ecotypes. In general, Kaliethan can be considered as the most suitable ecotype of 'Nendran' for commercial cultivation in Thiruvananthapuram and nearby areas. However, the o'h'i types such as Kothala, Chengazhikodan and Poovanchira typos can also perform well in this tract once they become adapt '1’ to the agroclimatic conditions of the zone.Item Enhancing the in vitro response of explants from mature jack (artocarpus heterophyllus lam.) trees(Department of Horticulture, College of Agriculture, Vellayani, 1993) Reena Philip; Rajmohan, KThe objective of the present study was to improve the propagation efficiency of mature phase jack trees by various pretreatments. The treatments tried involved stock plant treatments, explants treatments and in vitro treatments. Surface sterilization with HgCl2 for 13 minutes was found to be the most effective in reducing microbial contamination during culture establishment. Among the stock plant treatments tried, grafting on to juvenile rootstock was found to be the most effective in improving the in vitro response of explants from mature jack trees. Stress treatments were found to be the most effective among the explants treatments. Cold shock for 5 minutes at – 200C was found to produce the best results followed by heat treatment at 420 C for 2 minutes. Among the in vitro treatments, incorporation of phloroglucinol at the rate of 10mg/l was found to be the most effective. The results also showed significant influence of season on the response of mature explants, the highest response being observed during March – April.Item Standardization of postharvest processing of ginger (zingiber officinale roscoe)(Department of Horticulture, College of Agriculture, Vellayani, 1992) Ajith Kumar, K; Sreekandan Nair, GInvestigation on standardization of post-harvest processing of ginger (Zingiber officinale Roscoe) was carried out at the Department of Horticulture, College of Agriculture, Vellayani during 1988 -90. Ginger rhizomes were processed to study the effect of various methods like scraping, slicing, blanching, boiling, coating and their combinations on the yield and quality of dry ginger, storage life and also on storage pests and diseases adopting CRD. In this study among the various treatments low recovery (31.6 per cent) of dry ginger was obtained for scraped ginger. The sliced rhizomes took only four days for drying. The essential oil content decreased with an increase in time. The treatments slicing and drying (T4), blanching and drying (T5), unpealed and drying (T1) scraping and drying (T3) and spliting and drying (T2) were found to be the best for longer storage. The oleoresin content also decreased with an increase in time and the treatment combinations which include boiling resulted in the maximum reduction in oleoresin content followed in the maximum reduction in oleoresin content followed by combinations of scraping and spliting. The study revealed that compared to single treatment a combination of treatments especially when boiling as a component reduced the crude fibre content. The ginger rhizomes when sliced and dried took the minimum period for drying and it resulted in the production of normal coloured product and also comparable in quality aspects. Hence slicing and drying of ginger rhizomes is an alternate method for processing of ginger.