PG Thesis
Permanent URI for this collectionhttp://localhost:4000/handle/123456789/2
Browse
52 results
Search Results
Item Direct regeneration of banana(Musa spp.) cultivar njalipoovan through in vitro male bud culture.(Department of Fruit Science, College of Agriculture, Vellayani, 2025) Jovita Joju; Manju, P RThe 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 Management practices for shelf life extension of fresh cut jackfruit and pomegranate(Department of Postharvest Management, College of Agriculture,Vellanikkara, 2024-11-21) Amrutha, R; Athulya S KumarThe study entitled “Management practices for shelf life extension of fresh-cut jackfruit and pomegranate” was conducted at the Department of Postharvest Management, College of Agriculture, Vellayani during the period of 2022-2024, with the objective of standardizing the pre-treatments, packaging and storage systems for shelf life extension of jackfruit bulbs and pomegranate arils. The study was conducted as two separate experiments for jackfruit and pomegranate. Fresh, good quality, optimum mature jackfruit (Varikka) with relatively uniform size and weight were harvested from the Instructional Farm, Vellayani, allowed to ripe and used for the study; whereas good quality ripe pomegranate relatively of uniform size, weight and colour were procured from VFPCK outlet, Thiruvananthapuram and used for the study. Both the fruits were subjected to ozonization (2 ppm). Experiments were carried out in two parts viz., evaluation of pre-treatments and development of packaging and storage system. Jackfruit bulbs with seeds intact and pomegranate arils (100% usable form) were extracted from the sanitized fruits, pre-treated with four different solutions viz., 0.5% ascorbic acid, 0.5% citric acid, 1% calcium chloride and 1% calcium ascorbate for 4 minutes, air-dried and were kept in areca sheath bowls wrapped with cling film along with the corresponding untreated bulbs and arils (control), under refrigeration (5±2oC), to analyze the efficacy of pre-treatments. Pre-treated fresh-cut jackfruit bulbs and pomegranate arils resulted in better physical, physiological and chemical parameters as compared to the untreated ones. Pre treatment of jackfruit bulbs with 1% calcium ascorbate resulted in maximum shelf life (5.00 days), vitamin C (24.53 mg 100g-1), carotenoid (0.83 mg 100g-1), lowest physiological loss in weight (1.39 %), percent leakage (85.40%), acidity (0.31%), phenol (35.64 mg 100g-1), total sugar (37.59 %), reducing sugar (18.87 %) and TSS (23.80oB) with best sensory scores after 5 days of storage. During the initial, 1st, 2nd and 3rd days also, the physiological parameters were superior for calcium ascorbate treated bulbs. 184 Pomegranate arils treated with 1% calcium ascorbate recorded the maximum shelf life (5.00 days), vitamin C (23.26 mg 100g-1), anthocyanin (3.19 mg 100g-1), lowest physiological loss in weight (1.70%), percent leakage (39.17%), acidity (0.38%), phenol (210.99 mg 100g-1), total sugar (33.05%), reducing sugar (15.01%) and TSS (15.89oB) with best sensory scores after 5 days of storage. Hence, 1% calcium ascorbate was selected as the best pre-treatment solution for both fresh-cut jackfruit bulbs and pomegranate arils. In second part of the study, fresh-cut jackfruit bulbs and pomegranate arils treated with 1% calcium ascorbate solution, were subjected to different packaging systems viz., shrink wrapping in 15µ polyolefin film, vacuum packaging in laminated pouches, MAP with N2 flushing in laminated pouches, aluminium tray wrapped with cling film and open storage in paper plate (control) and stored under refrigerated (5±2°C) and low temperature (10±5°C) conditions. Pre-treated jackfruit bulbs in MAP with N2 flushing in laminated pouches stored under refrigerated condition (5±20C) recorded the maximum shelf life (10.00 days), vitamin C (20.18 mg 100g-1), carotenoid (0.77 mg 100g-1), least physiological loss in weight (4.86%), percent leakage (78.05%), acidity (0.38%), total sugar (39.37 %), reducing sugar (16.81%), TSS (23.25oB) and phenol (35.42 mg 100g-1) with best sensory scores after 10 days of storage. Fresh-cut jackfruit bulbs without any package (control) had the least shelf life (2.00 days) with maximum physiological loss in weight (3.26%) when kept under low temperature condition. Pre-treated pomegranate arils in MAP with N2 flushing in laminated pouches stored under low temperature condition resulted in maximum shelf life (6.00 days), vitamin C (23.02 mg 100g1), anthocyanin (2.87 mg 100g-1), least physiological loss in weight (3.88%), percent leakage (68.15%), acidity (0.42%), total sugar (35.46%), reducing sugar (17.15%), TSS (16.00oB) and phenol (214.16 mg 100g-1) with best sensory scores after 6 days of storage. Unpackaged arils stored under refrigerated condition recorded the least shelf life (2.00 days) with highest physiological loss in weight (5.10%). The fresh-cut jackfruit bulbs and pomegranate arils, pre-treated with 1% calcium ascorbate solution for 4 minutes and kept in MAP with N2 flushing in laminated pouches were microbiologically safe with superior physical, physiological and chemical parameters upto 10 days under refrigerated (5±20C) and 6 days under low temperature (10±50C) conditions respectively.Item Growth and yield estimation of rice based on satelite data and land based observation using growing degree days(GDD)(Department of Agricultural Meterology, College of Agriculture, Vellanikkara, 2024-03-21) Fazil; Ajith, KRice, the primary staple food for approximately 3.5 billion people worldwide, is supporting food security in numerous countries through irrigated as well as rainfed rice ecosystems. Elevated temperatures may lead to a decline in productivity, impacting the ability to feed future generations. To address this challenge, the utilization of temperature-based agrometeorological indices, such as Growing Degree Days (GDD) supported by satellite data, emerges as a valuable tool for predicting crop growth and yield across large areas. Growth and yield estimation of rice based on satellite data and land-based observation using growing degree days (GDD) conducted in the Department of Agricultural Meteorology, College of Agriculture, Vellanikkara during the year 2022-23 with the objective of establishing a relationship between GDD and performance of rice crop and to examine the possibilities of remote sensing tools to evaluate plant and GDD interactions to a wider area. The field experiment was conducted in two medium-duration rice varieties, Uma and Pournami, at the Regional Agricultural Research Station, Kumarakom during mundakan season of 2022-23, and was laid out in Randomized Block Design. The treatments consist of five dates of planting, viz. D1-5th September, D2-20th September, D3-5th October, D4-20th October, D5-5th November, with four replications. Various biometric observations, heat unit accumulations, yield and yield attributes were recorded at definite intervals. The study on phenology revealed that crop duration decreased from early planting to late planting in both varieties. Grain yield was significantly affected by the planting dates in both varieties. D1 planting produced the highest grain yield in both Uma (4388.8 kg ha-1) and Pournami (3715 kg ha-1) varieties, while D5 planting produced the lowest yield in Uma (2118.8 kg ha-1) and Pournami (2313.8 kg ha-1). The yield attributes were also significantly affected by planting dates and showed similar trend. Heat units like GDD and Photothermal units (PTU) were found to reduce in delayed planting. D2 recorded the highest GDD in both Uma (2055°C days) and Pournami (2090°C days). The lowest GDD was recorded by D5 planting in Uma (1820°C days) and Pournami (1872°C days). A linear regression equation was developed to predict yield for both varieties using GDD as independent variables. The results indicated that the Uma variety performed better than Pournami variety in the field experiment with respect to plant characters and yield. Palakkad district and Kuttanad. MODIS LST product (MOD11A2) 8-day composite was used to retrieve day and night land surface temperature for the mundakan rice growing season of 2022-23. A linear relationship was developed with MODIS LST and air temperature data obtained from the ground station. The developed relationship was then validated to ensure its accuracy and reliability. Daily maximum and minimum air temperature was estimated from MODIS LST using the linear equation during the crop season for the study locations. GDD was calculated, and it was employed to estimate the number of days required to attain various phenological stages of the mundakan rice. Validation of the predicted number of days in comparison with the observed showed a good relationship with R2 values of 0.82, 0.82, 0.80, 0.87, 0.86, and 0.81, and RMSE 0.42, 0.65, 0.72, 0.74, 0.84, 1.33 respectively, for the six phenophases of the rice crop. Further studies were done to assess the potential of GDD as an agroclimatic indicator for climate change in selected 9 locations in Palakkad and Kuttanad. The study attempted to understand the spatial and temporal distribution of GDD of mundakan rice over the past 30 years (1993-2022). The 30-year period were divided into six pentads. Additionally, GDD during three warming scenarios (+1°, +2° and +3°C rise of daily temperature from last pentad) were also studied. The research finding indicates that accumulated GDD was found to be higher at Kuttanad compared to Palakkad ie., GDD decreases from lower latitude to higher latitude. Chittur of Palakkad district had the lowest accumulation of GDD, while the highest was reported at Moncompu in Kuttanad in the last pentad and as well as during the three warming scenarios. Analysis of the 30 year GDD data of Palakkad revealed that an alternate warming and cooling trend is observed during the first four pentads (i.e. the period from 1993 to 2012) and during the last two pentads (ie. period from 2013 to 2022) the cooling trend is not visible. In Kuttanad region the warming trend is more predominant and the GDD values showed a steady increase form the first pentad to the last pentad. The GDD values seems to decrease from west to east in both Palakkad and Kuttanad.Item Native ornamentals for water- wise landscaping(Department of Floriculture and Landscaping, College of Agriculture , Vellanikkara, 2024-03-05) Bhukya Mahesh; Shajma Nafeesa BasheerThe investigation entitled “Native ornamentals for water-wise landscaping” was conducted in the Department of Floriculture and Landscaping, College of Agriculture, Vellanikkara, with an objective to conduct the morphological evaluation of native ornamentals and to assess the suitability of selected native ornamentals for water wise landscaping. The study was conducted as two experiments i.e., morphological evaluation of native ornamental species and evaluation of native ornamental plants for drought stress tolerance. The native species selected for the first study were Murraya paniculata, Barleria mysorensis, Rauwolfia tetraphylla, Barleria strigosa, Clerodendrum inermi, Carmona retusa, Melastoma malabathricum, Ecbolium viride, Eranthemum capensis and Pogostemon quadrifolius. Significant variations were observed for vegetative and flower characters and air pollution tolerance index among the ten native species. Maximum plant height was observed in Murraya paniculata (65.00 cm), which was on par with Clerodendrum inermi (60.87cm). Plant spread was also maximum in Murraya paniculata (41.33 cm). The number of primary branches was the highest in Clerodendrum inermi (6.43), which was on par with Pogostemon quadrifolius (6.15). Clerodendrum inermi also recorded the highest number of secondary branches (11.33), which was on par with Eranthemum capensis (10.33). The highest number of leaves was observed in Clerodendrum inermi (95.33). The leaf length recorded the highest value in Ecbolium viride (9.01 cm), which was on par with Barleria strigosa (8.00 cm). The leaf breadth was recorded highest in Barleria strigosa (7.33 cm) followed by Eranthemum capensis (4.33 cm). The qualitative vegetative characters like leaf type (simple/ compound), shape of leaf lamina, type of leaf base, margin and tip, leaf surface texture (coarse or fine), pubescence (present or absent) and leaf colour (as per RHS colour chart) were also exhibited wide variability. Among the floral characters, the maximum flower diameter was recorded in Melastoma malabathricum (4.83 cm), maximum length of the flower stalk in Barleria strigosa (3.67 cm), maximum number of flowers in Barleria mysorensis (50.00), flowering duration in Melastoma malabathricum (7.33 months) and field life of flowers in Barleria strigosa (3.67 days). Qualitative characters of flowers like flower type (solitary / inflorescence), colour of flower (as per RHS colour chart), fragrance (presence/absence), season of flowering and field life of flowers (days) also recorded wide variation. Based on their APTI value Carmona retusa can thus be included under the moderate tolerant group and Pogostemon quadrifolius under the sensitive group. Melastoma malabathricum can be used as edge, hedge and flower borders. Murraya paniculata having the highest plant height and plant spread can be used as hedge. Barleria strigosa can be used for hedge planting. Clerodendrum inermi which recorded the highest number of leaves and plant height can be used as hedge and for topiary. In the second experiment the native ornamentals were evaluated for their drought stress tolerance. Morphological characters like plant height, shoot and root biomass, stem diameter, leaf fresh and dry weight and stem diameter decreased in drought condition when compared to control. Total root length and root-shoot ratio increased under drought condition compared to control. Physiological parameters like RWC and membrane stability reduced under 5-day and 10-day water stress. Biochemical parameters photosynthetic pigments and starch decreased under 5 day and 10-day stress. Anatomical characters like higher stomatal index and lowest cell size were observed in plants subjected to 10-day stress. Clerodendrum inermi recorded the highest root length (92 cm) under 10-day stress. Clerodendrum inermi recorded highest relative water content (86.98 %) under control. Rauwolfia tetraphylla recorded the highest root-shoot ratio (0.97), carotenoid (0.10 mg/g), proline (96.44 μmol g-1FW) and MDA (1.63 μmol g-1FW) under 10-day water stress. Barleria mysorensis showed the highest membrane stability index (100.46) and lowest MDA (0.14 μmol g-1FW) under control. Thus Rauwolfia tetraphylla, Clerodendrum inermi, Murraya paniculata, Melastoma malabathricum and Barleria mysorensis can be suitably used for water-wise landscapingItem Pests of exotic fruit crops in Kerala(Department of Entomology, College of Agriculture, Vellayani, 2024-02-27) Akheela, P; Thanima Sara VargheseThe study entitled “Pests of exotic fruit crops in Kerala.” was conducted at the Department of Entomology, College of Agriculture, Vellayani from 2021 to 2023 with the objective of documenting the pests of exotic fruits, its natural enemies and pollinators in Kerala. The documentation was carried out at the orchard of Instructional Farm, Vellayani and in farmer’s field in Thiruvananthapuram, Kollam, Kottayam and Malappuram districts of Kerala through multiple field visits. A total of 60 different pests were documented from different exotic fruit crops. Among them, 32 pests were documented from rambutan Nephelium lappaceum (L.), 8 from dragon fruit Selenicereus undatus (Haw.) D. R. Hunt, 7 from mangosteen Garcinia mangostana (L.), 4 from passion fruit Passiflora edulis (Sim.), and 10 from other minor exotic fruit crops like miracle fruit Synsepalum dulcificum (Schumach. and Thonn.), pulasan Nephelium mutabile (Blume.), abiu Pouteria caimito (Radik.), soursop Annona muricata (L.), litchi Litchi chinensis (Sonn.), velvet apple Diospyros discolor (Willd.) and longan Dimocarpus longan (Lour.). Leaf and inflorescence caterpillars were predominant in rambutan followed by sucking pests and beetles. The sucking pests include, mealybug Planococcus lilacinus (Cockerel), Crisicoccus hirsutus (Newstead), Ferrisia virgata (Cockerell), scale Ceroplastis floridensis (Comstock), Icerya sp., bean bug Riptortus pedestris (Fabricius), cow bug Otinotus oneratulus (Walker), tree hopper Gargara sp., black plant hopper Ricania sp., flatid plant hopper Flatormenis sp. The lepidopterans recorded in rambutan were white looper moth Pingasa chlora (Stoll), slate flash Rapala manea (Hewitson), emerald moth Hemithea tritonaria (Walker), yellow-tail tussock moth Somena scintillans (Walker), tussock caterpillar Olene mendosa (Huebner), looper Comibaena cassidara (Guenee), pointed ciliate blue Anthene lycaenina (Felder), owl moth Avatha discolor (Fabricius) and a bark borer which is an unidentified micro lepidopteran. Scarab beetle Popillia sp., warty leaf beetle Exema salemensis (Bhasin), leaf beetle Monolepta sp. and flower beetle Oxycetonia versicolor (Fabricius) were the coleopteran pests documented on rambutan. Rambutan was identified as the host for the above-mentioned pests for the first time in India. In dragon fruit, the oriental fruit fly Bactrocera dorsalis (Hendel) was reported for the first time in India. The sucking pests like the brown stink bug Halyomorpha picus (Fabricius), plant hopper Eurybrachis sp., Ricania sp. and Flatormenis sp., striped mealybug Ferrisia virgata (Cockerell), and a destructive trailing ant Trichomyrmex destructor (Jerdon) were also reported for the first time as insect pests of dragon fruit from India. Pest infestation was comparatively lower in mangosteen and passion fruit. The brown soft scale Coccus hesperidum (Linnaeus), mealybug C. hirsutus, leaf eating caterpillar Agrotera flavobasalis (Inoue) and flower feeding caterpillar Homona sp. were reported for the first time in mangosteen from India. The rugose spiralling whitefly Aleurodicus rugioperculatus (Martin) and gold tail moth Sphrageidus xanthorrhoea (Kollar) were reported for the first time in passion fruit from India. Biology of B. dorsalis, H. picus and S. xanthorrhoea were studied under laboratory condition. The egg, larval, pupal and adult period of male, female B. dorsalis in dragon fruit were 1.6± 0.40, 8.0 ± 0.40, 8.0 ± 0.31, 6.4 ± 0.50 and 9.6 ± 0.5 days respectively. The egg, larval and pupal period of S. xanthorrhoea 5.2 + 0.20, 25.6 ± 1.20, 6.6 ± 0.37 days respectievely. Adult period of male and female were 4.4 ± 0.24 and 6 ± 0.44 days respectively. The egg and nymphal periods for H. picus were 5.2 ± 0.20 and 46.8 ± 2.53 days, respectively. Spiders were the dominant predators of the pests of exotic fruits. A total of 24 natural enemies were documented from exotic fruit crops, which include spiders (15), hymenopteran parasitoids (3) and insect predators (6) belonging to Coleoptera (1), Lepidoptera (1), Mantodea (3) and Hemiptera (1). The hymenopteran parasitoids documented were from the family Eupelmidae, Aphelinidae and Trichogrammatidae. For the documentation of pollinators, a study was conducted during the flowering season of rambutan and passion fruit at Instructional Farm Vellayani. For documentation of pollinators of rambutan, five inflorescences each were selected randomly from five different trees. Population of pollinators was recorded by visual observation once in a week from 0600 to 1800 h for a period of four weeks. For documentation of pollinators of passion fruit, the same methodology was adopted for plant selection and pollinators were recorded once in four weeks from 1200 to 1800 h for a period of four weeks. Ten pollinators were recorded from rambutan and four were from passion fruit. The pollinators documented belong to Hymenoptera (9) Diptera (3) and Lepidoptera (2). Stingless bee Tetragonula travancorica (Shanas and Faseeh) was the most abundant and frequent flower visitor of rambutan and carpenter bee (Xylocopa sp.) was the frequent visitor of passion fruit flowers. Seasonal incidence of pests infesting rambutan was carried out for one year from November 2022 to November 2023. The presence of pests in rambutan was noted specifically from March to July, encompassing the flowering to fruit-setting season. The peak pest infestation had a positive correlation with the temperature in rambutan. In the course of the current investigation, a comprehensive catalogue of 60 pests, 24 natural enemies, and 14 pollinators were documented from exotic fruits in Kerala. Among the identified pests 27 pests were recorded from the order Hemiptera, 21 from Lepidoptera, 6 from Coleoptera, 4 from Hymenoptera and 2 from Diptera. Rambutan has been documented to have 14 pests from the order Lepidoptera, 11 from Hemiptera, 5 from Coleoptera, and 2 from Hymenoptera. Dragon fruit pests include 5 from Hemiptera, 1 from Lepidoptera, 1 from Diptera, and 1 from Hymenoptera. Mangosteen pests belong to the order Hemiptera (3), Lepidoptera (3), and Hymenoptera (1). Passion fruit pests include 2 from Hemiptera, 1 from Lepidoptera, and 1 from Diptera. Minor exotic fruits have pests from Hemiptera (6), Lepidoptera (3), and Coleoptera (1).Spiders emerged as the predominant predators associated with the exotic fruit pests. Hymenopteran pollinators stood out as the most abundant contributors to pollination where stingless bee (T. travancorica) was the most abundant and frequent flower visitor of rambutan and carpenter bee (Xylocopa sp.) was the frequent visitor of passion fruit flowers. The pest incidence in rambutan showed a positive correlationItem Managerial efficiency of cashew growers in Kerala and Tamil Nadu: a comparative analysis(Department of Agricultural Extension Education, College of Agriculture, Vellayani, 2025) Mohamed Aseemudheen, M.; Esakkimuthu, MThe research work entitled “Managerial efficiency of cashew growers in Kerala and Tamil Nadu: A comparative analysis” conducted at the College of Agriculture, Vellayani, Thiruvananthapuram, Kerala during the academic year 2022-24. The study objectives are to assess managerial efficiency of cashew growers; perception of cashew growers on area expansion, replanting senile and unthrifty cashew plantations; extent of adoption of technological interventions in cashew cultivation; knowledge and attitude of cashew growers on product diversification and value addition. The study employed analytical research design and followed a multi-stage purposive sampling method for diverse representation in Kerala and Tamil Nadu. Kannur and Cuddalore, the top cashew-producing districts, were selected. In Kannur, 80 growers were chosen, 40 from Iritty block across Kacherikadavu (20) and Payam (20) Gram Panchayat and 40 from Peravoor block across Kelakam (20) and Kottiyoor Gram Panchayat (20). In Cuddalore, 80 growers were selected, 40 from Panruti block across Alagappasamuthiram (20) and Arasadikuppam (20) and 40 from Kammapuram block across Kotteri (20) and Muthanai (20). Data collection involved a pre-tested and structured interview schedule. It was analyzed using statistical techniques such as frequency, percentage, mean, standard deviation, quartile deviation, Rasch-Andrich analysis, t-test and correlation analysis. The socio-economic findings revealed notable differences between Kerala and Tamil Nadu cashew growers. In Kerala, 30.00% of respondents were in late adulthood, while Tamil Nadu had a more balanced age distribution with 28.75% in late adulthood and 27.50% in early adulthood. Male dominance was evident in both states, with 95.00% of growers in Kerala and 92.50% in Tamil Nadu being male. Kerala exhibited higher literacy with no illiteracy, while Tamil Nadu had broader educational diversity, including 7.50% illiteracy and more technical diploma holders (13.75%). Landholding patterns showed Kerala’s dominance of smallholders (62.50%), whereas Tamil Nadu had 36.25% marginal landholders and 11.25% leasing land. Kerala’s growers operated smaller plots (48.75%), while Tamil Nadu utilized more leased land (16.25%). Proficient farmers were more common in Kerala (27.50%), while Tamil Nadu had more advanced beginners (38.75%). Family sizes were larger in Kerala The managerial efficiency of cashew growers varied across eight components, reflecting regional strengths and weaknesses. In Kerala, 31.20% of farmers were efficient in planning and 33.80% were moderately efficient in decision-making, while organizing and coordinating posed challenges, with 36.20% and 41.30% being less efficient, respectively. Tamil Nadu growers performed better in organizing (33.75% highly efficient), budgeting (37.50% efficient) and marketing (31.25% highly efficient), supported by established processing industries and market integration. Kerala had 33.75% of growers categorized as efficient overall, while Tamil Nadu had 26.25% in the highly efficient category, indicating a need for region-specific interventions to enhance overall efficiency. Entrepreneurial ability among cashew growers was predominantly at a medium level, with 55.00% in Kerala and 57.50% in Tamil Nadu falling into this category. High entrepreneurial ability was observed in 23.75% of growers in Kerala and 22.50% in Tamil Nadu, while low ability was reported among 21.25% and 20.00% of growers, respectively. Perception of area expansion and replantation was medium for 57.50% of Kerala respondents and 61.25% in Tamil Nadu. Adoption of technological interventions showed a medium level in both states, though Tamil Nadu (18.75%) had higher adoption rates than Kerala (7.50%). Knowledge of product diversification and value addition was medium for 53.75% of Kerala growers and 62.50% of Tamil Nadu (76.25% with large families), contrasting with Tamil Nadu (60.00% small families). Annual income placed 40.00% of Kerala farmers in the lower-middle-income group, compared to 52.50% in Tamil Nadu. Training attendance was low in both states, with 93.75% of Kerala growers and 86.25% in Tamil Nadu participating minimally. Information-seeking behavior revealed Kerala’s reliance on family and acquaintances (46.56%) and Tamil Nadu’s greater use of social media (54.38%). Market intelligence was average for 73.75% of Kerala farmers, while Tamil Nadu had 38.75% with superior intelligence. Economic motivation was medium for most growers in both states, though Tamil Nadu had a higher proportion of highly motivated farmers (33.75%). Kerala farmers were more confident (42.50% very confident) and had higher achievement motivation (77.50% medium motivation) compared to Tamil Nadu. Major constraints included pest and disease infestations (100.00%) in both states. Kerala struggled with limited labour availability (97.50%) and market monopolies (92.50%), while Tamil Nadu faced climate variability (93.75%) and high input costs (87.50%). In both states, inadequate irrigation and insufficient infrastructure for value addition further hindered growers' ability to enhance productivity and profitability. Policy recommendations include youth engagement, infrastructure development, market intelligence and climate resilience. Future research could explore broader cashew-growing regions, evaluate policy effectiveness and investigate advanced practices in value addition, climate resilience and digital tools to enhance cashew cultivation sustainability. growers. Similarly, attitudes toward value addition were predominantly medium in both states.Item Economic analysis of production and marketing of raw cashewnut in kerala(Department of Agricultural Economics, College of Agriculture ,Vellanikkaraa, 2024-03-14) Chenna srilakshmi; Prema, ACashew (Anacardium occidentale L.), a perennial tree native to Eastern Brazil is globally recognized for its commercial significance. India, holding the position of the world's second largest raw cashew producer, accounts for 22.32 per cent of global raw cashew production. Maharashtra leads cashew production in India, followed by other states. India the second largest exporter of cashew nuts, representing over 65 per cent of global cashew kernel exports. Kerala, a major cashew producer in India, has an area and production of 1.06 lakh hectares and 0.71 lakh tonnes, respectively. Despite having the highest processing capacity in India, Kerala faces challenges due to insufficient domestic production, leading to dependency on imported raw cashew nuts. It highlights the significance of area expansion under cashew cultivation in Kerala and there is a need to assess economic aspects along with constraints. In this context, the study entitled ‘Economic analysis of production and marketing of raw cashew nut in Kerala’ was undertaken with the objectives: Analysing the trends in area, production and productivity of raw cashew nut, estimating the economics of raw cashew nut production and marketing, analysing the price behaviour of raw cashew nut, delineation of major challenges faced by cashew farmers. The micro level study was conducted in Kannur and Kollam districts. Kannur has the highest area under cashew cultivation in Kerala. Kollam has been showing a declining trend over the years, and revival of cashew cultivation has been reported recently. From each district, two blocks with maximum area under cashew i.e., Iritty and Irikkur from Kannur district; Anchal and Kottarakkara from Kollam were purposively selected. From each selected blocks, three panchayats were randomly selected. Fifteen farmers from each panchayath in Kannur (90) and five farmers from each panchayath in Kollam (30) were randomly selected, making a total of 120 farmers. Further data was collected from 20 market intermediaries and 10 officials from line departments making a total sample size of 150. India showed positive trend in area and production of raw cashew nuts, while Kerala exhibited negative trend in these aspects, and has exhibited positive trend in productivity. The establishment costs of raw cashew were estimated as ₹1,36,031 and ₹1,16,697 per hectare for Kannur and Kollam, respectively. The average maintenance cost was estimated as ₹42,960 in Kannur and the maintenance cost for yield increasing phase was ₹26292 per hectare in Kollam. The estimation of total cost of cultivation was confined to Kannur district and was worked out as ₹57,816 per hectare per year and the cost of production as ₹65/kg. The efficiency of raw cashew cultivation was analysed using the Cobb-Douglas production function. The quantity of organic manures and human labour were found to be significant at five and ten per cent level of significance respectively. In Kannur, four marketing channels were identified: channel I: Producer-village trader-wholesaler-processing units, channel II: Producer-itinerant traders-wholesaler processing units, channel III: Producer- wholesaler- processing units, channel IV: Producer-Fair Trade Alliance Kerala agent (FTAK) – FTAK. whereas only two channels in Kollam as channel I: Producer- village traders-processing units and channel II: Producer-processing units. The highest marketing efficiency was observed in channels IV and III in Kannur, while in Kollam, it was highest in channel II followed by channel I. Channel IV and III in Kannur had the highest producer's share in consumer's rupee, with 94 per cent and 92 per cent, respectively. While in Kollam, channel II had the highest producer's share of 98 per cent. The price behaviour analysis indicated that there is an increasing price trend over the years from 2006 to 2023 and seasonality existed with highest prices in January, February months and it was observed decreased prices in May and June months due to onset of monsoon resulting in raw nut quality deterioration and fechting lower price. Cyclical variations with two cycles and irregular variations found to be less predominant. The constraints affecting cashew production in Kannur included the presence of tea mosquito bug and cashew stem and root borer, unfavourable weather, high labour costs, and untimely supply of raw materials by the government. Additionally, scattered land holdings and a lack of technical knowledge were also observed in Kollam. Marketing constraints include low price, Price fluctuations, non- receipt of the announced price by the Kerala State Cashew Development Corporation were common marketing constraints for both districts, along with exploitation by middlemen and lack of drying and processing units were the constraints in Kannur district. Farmers should adhere to recommended agricultural practices and participate in training programs which would enhance the technical knowledge. Promoting farmer producer organizations can bring economics of scale, while the establishment of processing units in Kannur can enable farmers to process and involve in direct export. To generate additional income, there is a need to commercialize cashew apple value addition and waste utilization, such as producing industrial ethanol, cashew fenny, and cashew honey etc. Market innovation is essential for ensuring grading and maintaining the reputation of 'Kerala cashew' for its superior quality and taste.Item Performance potential of organic amendments derived from invasive aquatic weed, Limnocharis flava (L.) Buchenau(Department of Soil Science and Agricultural Chemistry, College of Agriculture,Vellayani, 2025-01-27) Ambili, S.; Meera, A VThe study entitled “Performance potential of organic amendments derived from invasive aquatic weed, Limnocharis flava (L.) Buchenau” was conducted at College of Agriculture, Vellayani and Integrated Farming System Research Station, Karamana during the period 2022-24. The objectives of the study were production of different organic amendments from the aquatic weed, Limnocharis flava and assessment of their impact on soil health and productivity of okra. Different amendments viz., ordinary compost (OC), vermicompost (VC), microbial compost using solid inoculum (SMC), microbial compost using liquid inoculum (LMC) and biochar (BC) were produced and evaluated. The amendments produced were characterized for physical, electro chemical, chemical and biological properties. The mean residence time for BC production was 1-2 hr. at 300-400 °C and the recovery percentage was 26.16. Recovery % for OC, VC, SMC and LMC were 8.40, 15.10, 11.05 and 12.22, respectively, while composting period was 78, 62, 59 and 50 days. BC recorded the bulk density (0.33 Mg m-3), water holding capacity (261.33 %), pH (9.25), EC (6.42 dS m-1), CEC (13.75 cmol (+) kg-1), AEC (8.72 cmol (-) kg-1), total organic carbon (74.89 %) and C:N ratio (82.39). The highest N (2.14 %) content and lowest C:N ratio (32.32) were obtained for VC. P content (0.73 %) was highest for LMC. K, secondary nutrients (Ca, Mg, S) and micronutrients (Fe, Mn, Zn, Cu and B) were also highest for BC. Heavy metal content was below the detectable level in both source material and the amendments produced. A field experiment was conducted to study the effect of different organic amendments on soil health and crop productivity using okra (variety: Salkeerthi) as the test crop. The treatments included amendments produced @ 25 t ha-1 along with 100 and 75 % of recommended dose of fertilizers (RDF), FYM @ 25 t ha-1 along with 100 % RDF and absolute control. The different amendments had significantly influenced the biometric and yield parameters of okra. Plant height, chlorophyll content, yield and yield attributes and biomass yield were highest for VC along with 100% RDF. Significant improvement in soil physical, chemical and biological properties were observed on applying the organic amendments. The highest yield of 23.70 t ha-1 was obtained for T3 (VC @ 25 t ha-1 + 100% N: P2O5:K2O), which was 88 % higher over absolute control and 58 % higher over Package of Practices Recommendations. BC along with 100 % RDF recorded 91.05 and 57.05 % yield improvement over control and PoP. Total N, P, K, Ca, S, Mn, Zn, Cu, and B uptake by plants were also highest for VC along with 100% RDF (T3). The highest Fe uptake was observed in VC along with 75 % RDF (T4). Mg uptake was highest for LMC along with 100% RDF. The different amendments had resulted in decrease in bulk density and increase in water holding capacity, pH, EC, CEC and AEC of postharvest soil. T3 (VC + 100% N: P2O5:K2O) recorded the highest value for available N (393.05 kg ha-1) and dehydrogenase (199.74 μg TPF g-1 soil 24 h-1) activity. Available P2O5 (91.34 kg ha-1) and Fe (246 mg kg-1) were highest for LMC + 100% N: P2O5:K2O (T7). BC + 100% N: P2O5:K2O (T9) recorded the highest values for K (224.82 kg ha-1), Ca (391.67 mg kg-1), Mg (62.00 mg kg-1) and S (20.10 mg kg-1) while Mn (55.74 mg kg-1), Zn (190.50 mg kg-1), Cu (5.33 mg kg-1) and B (0.69 mg kg-1) were highest for BC along with 75% N: P2O5:K2O (T10). Yield parameters viz., total fruit yield, fruit yield per plant and fruit length were on par for the treatments applied with vermicompost along with 100 (T3) and 75 % RDF (T4). B: C ratio was also found to be 2.01 for both the treatments. Application of biochar produced from the weed resulted in very good improvement in the physical and electrochemical properties and secondary and micro nutrient contents of the soil. The nutrient composition of amendments varied with the method of conversion. Hence, it could be concluded that application of L. flava vermicompost @ 25 t ha-1 along with 75 % RDF could be recommended for cultivating okra and could be considered as the economically viable option for utilization of this aquatic weed. Incorporation of L. flava biochar helped in improving the soil physical and chemical attributes. L. flava using different composting strategies using vermicompost, biochar, etc. along with inorganic nutrients can be utilized as effective strategies for disposal of weed and to improve soil health and crop productivity.Item Forest biomass dynamics using forest inventory data of Kerala(College of Climate Change and Environmental Science, Vellanikkara, 2024-07-26) Gopika S Pillai; Vinay Kumar DhadhwalThe study focuses on the dynamics of forest carbon. The objectives of the study is to estimate the forest carbon dynamics using Working Plans and Geographic Information System (GIS) techniques and analysis of carbon stock. Idukki and Palakkad districts of the state of Kerala are chosen as the study areas since they are the two districts with the highest forest cover in the state. Working plans (WP) prepared by Kerala Forest department, India State Forest Report prepared by Forest Survey of India (FSI) and data from published literatures are being used for the study. GIS technologies are used for the mapping and the estimation of the area of different plantation types and Reserve Forest of both districts. The forest beat boundaries of both the districts are mapped as well. The area obtained through mapping is corroborated with forest cover area as mentioned in the FSI reports. Around 1130 square kilometers of plantation area is present in Idukki district, which accounts for about 22 per cent of its geographical area. Tea, Cardamom and Eucalyptus occupy the largest areas of plantation respectively. Reserve Forests (RF) spans around an area 2800 square kilometers of the district accounting for approximately 55 per cent of its Geographical Area. The largest reserve forests are Malayattur, Periyar and Thodupuzha RF. In case of Palakkad district, around 370 sq. km of plantation area is present, accounting for about 8 per cent of the district’s geographical area. Teak, Rubber and Cashew occupy the largest area among all of the plantation types respectively. About 2130 sq. km of Reserve Forest area is present in Palakkad district which is around 47 per cent of the geographical area. From the estimation of natural forest tree cover loss and plantation tree cover loss (of the past two decades), it could be noted that the highest natural forest tree cover loss was during 2018-19 period in both the districts- around 900 ha and 750 ha in Idukki and Palakkad districts respectively. Whereas in the case of plantation tree cover loss, the highest loss was noted during the period of 2011-12 in Idukki district (100-120 ha) and 2018-19 in Palakkad district (220-250 ha). Spatial mapping of Above Ground Biomass (AGB) from the published data of Santoro indicates that the highest AGB is found in forest beat areas which is around 109 to 239 million tonnes and 88 to 240 million tonnes in Idukki and Palakkad districts respectively. For the teak plantation analysis, the age of the teak plantations of each range is calculated from the year of plantation and year of harvesting as mentioned in the WPs of the respective ranges. Whether the parameter is Mean Annual Increment (MAI) or Growing Stock (GS) or Volume of timber or Mass of firewood, they are heavily influenced by the age of the plantation tree along with certain other components like site quality and topography. The productivity of plantation trees is maximum around the mid 40 years of age and also, increases considerably after 60 years of age. The volume of different species belonging to the natural forests of the selected ranges of Idukki district are estimated. In the Kothamangalam division, Pali occupies the highest volume, meanwhile in the Anakulam and Mankulam ranges of Mankulam division, Nanku and Miscellaneous species occupy the highest volume respectively.Item Exploration of potassium dynamics in coarse textured soils and saline hydromorphic soils of Kerala(Department of Soil Science and Agricultural Chemistry, College of Agriculture , Padanakkad, 2024-12-10) Akhila Chandran, S; Binitha, N KSoil, being a dynamic entity of heterogeneous nature formed from the weathering of rocks and minerals varies in its physical, chemical as well as biological properties spatially and temporally. Potassium, the third major plant nutrient is present in soil mainly in mineral form such as feldspar and mica. Solution K, exchangeable K, non-exchangeable K and total K are the four different pools of potassium that are present in soil and are in constant equilibrium with one another. The study entitled "Exploration of potassium dynamics in two selected soil types of Kerala" investigated K dynamics of K-deficient coarse-textured northern coastal soils from AEU 2 and K-rich saline hydromorphic soils of Kaipad from AEU 7 in Kerala. The research also focused on the role of potassium solubilizing bacteria (KSB) in facilitating K release from minerals (feldspar and mica) and its impact on growth and yield of cowpea. Soil samples were collected from 10 locations in each agro-ecological unit (AEU) at depths of 0-20 cm and 20-40 cm, followed by an incubation experiment and pot culture study. Saline hydromorphic soils showed higher moisture retention, nutrient content, and microbial activity compared to northern coastal soils. Both soil types showed decreasing pH, EC, and biological activity with depth. In soils of AEU 2, available K at 0-20 cm ranged from 41.44 to 142.35 kg/ha , while at 20-40 cm it ranged from 39.02 to 137.93 kg/ha. Water-soluble K was observed to be very low, ranging from 1.68 to 45.65 kg/ha at 0-20 cm, and 5.61 to 48.17 kg/ha at 20-40 cm. Exchangeable K was also low, ranging from 9.85 to 120.38 kg/ha at 0-20 cm and decreased at 20-40 cm. Acid-soluble K, representing non-exchangeable reserves, varied from 62.16 to 182.56 kg/ha at 0-20 cm and increased to 78.07 to 194.47 kg/ha at 20-40 cm. Conversely, soils of AEU 7 showed far greater K availability with available K at 0-20 cm ranging from 644 to 1603 kg/ha and 704 to 1684 kg/ha at 20-40 cm. Water-soluble K levels were also higher, ranging from 415.18 to 927.14 kg/ha at 0-20 cm and 373.24 to 857.25 kg/ha at 20-40 cm. Exchangeable K was highest in saline soils, reaching up to 695.8 kg/ha, while acid-soluble K peaked at 1286.88 kg/ha, indicating much higher nutrient reserves and fertility compared to northern coastal soils. Soils of AEU 2 had lower nitrogen, phosphorus, and sulfur with nutrient levels decreasing with depth. In contrast, soils of AEU 7 exhibited higher nitrogen, phosphorus, and sulfur maintaining or increasing with depth. Calcium and magnesium levels were also significantly higher in saline soils, reflecting greater fertility compared to the nutrient-poor coastal soils. The incubation study focused on the effect of potassium solubilizing bacteria (KSB) on K release from feldspar and mica in northern coastal and saline hydromorphic soils over a period of 100 days. In northern coastal soils, the highest available K was observed in the feldspar + KSB treatment (T3), increasing from 221.87 kg/ha on day 25 to 498.96 kg/ha by day 100. Water-soluble K peaked in T4 (mica + KSB), reaching 63.54 kg/ha by day 100. In saline hydromorphic soils, KSB with feldspar (T3) showed the highest available K, increasing from 3399.76 kg/ha on day 25 to 4331.04 kg/ha by day 100. Water-soluble K in these soils reached 1027.15 kg/ha in T3. Overall, KSB significantly enhanced potassium release, with feldspar proving more effective than mica over time, particularly in potassium-rich saline hydromorphic soils. By conducting pot culture experiment it was identified that in northern coastal soils, feldspar treatment (T3) resulted in the highest pod yield and seed yield. In saline hydromorphic soils, the mica treatment (T4) produced the highest pod yield. Post-harvest soil analysis showed that available potassium was highest in the feldspar treatment (T3) in both AEU 2 (103.48 kg/ha) and AEU 7 (4331.04 kg/ha). Significant increases in nutrient uptake by plants, microbial biomass carbon and dehydrogenase activity were observed in KSB- treated soils, indicating enhanced microbial activity and nutrient cycling. The study could illustrate the spatial as well as depth wise variation of various physical, chemical and biological parameters in different agro-ecological units. The successive incubation and pot culture experiments could demonstrate that KSB can play crucial role in enhancing potassium release from mineral sources, especially feldspar, which is more effective than mica in both K-deficient and K-rich soils. In K-deficient northern coastal soils, KSB combined with feldspar significantly increased potassium availability, crop growth, and yield. Saline hydromorphic soils, with naturally higher potassium levels, also benefited from KSB treatments leading to improved nutrient availability and plant growth. The findings suggest that integrating KSB with mineral potassium sources can be an effective strategy to enhance soil fertility and crop productivity in varying soil conditions.