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ThesisItem Open Access Influence of vegetation on the hydrologic characteristics of Irumbupalam and Mayiladumpara watersheds in Peechi - Vazhani wildlife sanctuary, Thrissur, Kerala(Department of Natural Resource Management, College of Forestry, Vellanikkara, 2022-10-25) Bhawane Akash, Kailas; KAU; Gopakumar, SForest vegetation and water are two valuable resources for mankind, and both the resources influence each other. It is important to understand the interrelationship between forest vegetation and hydrology. The present study was undertaken in Irumbupalam and Mayiladumpara watersheds in Peechi-Vazhani wildlife sanctuary, Thrissur, Kerala. The aim of the study was to identify and quantify the hydrological differences between these watersheds and assess the extent to which these differences are related to vegetation characteristics. Mayiladumpara watershed comprised of eight different land use classes of which mixed crops and trees accounts highest (27.91%) area whereas Irumbupalam comprised of three land use classes, of which, reserved forest occupied the highest (67.74%) of area. Within each watershed, twenty-two, 10 m x 10 m sample plots were laid out for detailed enumeration of vegetation and soil parameters. The Irumbupalam harbored a greater number of tree species (38) compared to the Mayiladumpara (28). The mean tree density ha-1 was higher in Mayiladumpara (586 individuals ha-1 ) compared to Irumbupalam (509 individuals ha-1 ). Similarly, the mean tree basal area was greater in Mayiladumpara (45.48 m2 ha-1 ) as compared to Irumbupalam (13.97 m2 ha-1 ). The tree diversity was found to be maximum in Irumbupalam watershed. Physico- chemical properties of soil viz. soil pH, organic carbon, water holding capacity, soil moisture and soil porosity showed showed higher values for Irumbupalam watershed. There were differences in terms of soil physico- chemical properties in watersheds between pre-monsoon and monsoon season. The highest values for soil pH (5.87-7.05), C (2.12-6.61%), porosity (41.42-44.95 %), WHC (41.85-72.92 %), SM (9.2- 44.07 %) was recorded in Irumbupalam. Whereas, BD (0.74-1.64 gm cm-3) values were higher in Mayiladumpara than Irumbupalam. Canonical correspondence analysis (CCA) showed a complex interrelationship amongst species clustering, site and soil properties. 118 Mean annual precipitation for both watersheds were recorded. Stream flow measurements were taken monthly for stream depth and stream velocity using float method. Groundwater levels observations was taken monthly from selected wells. Water quality parameter was assessed monthly from upstream, mid-stream and downstream points for both watersheds. Mean rainfall for Irumbupalam and Mayiladumpara for the period (2017-21) was 457 mm and 514.8 mm respectively in the pre-monsoon season, and 1555.5 mm and 1567.7 mm in the monsoon season. Mayiladumpara's monthly streamflow was always higher than Irumbupalam. The pre-monsoon water yield of well was higher in Irumbupalam as compared to Mayiladumpara. The Irumbupalam watershed always had a higher water table than the Mayiladumpara watershed. Stream water temperature (WT), total dissolved solids (TDS), electrical conductivity (EC), turbidity, nitrate (NO3- ) were significantly (p<0.05) higher in Mayiladumpara Irumbupalam. In contrast, dissolved oxygen (DO) and pH of water was significantly higher (p<0.05) in the Irumbupalam. Seasonal variation was observed in the physico-chemical properties of stream water both in watersheds over the study period of eight months. Pearson correlation coefficient revealed that canopy closure was significantly related to some hydrological parameters. Canopy closure was significantly correlated with four water physico-chemical parameters (p<0.05) viz., dissolved oxygen (DO), temperature, electrical conductivity (EC), (NO3-). This indicated that canopy closure is related to water quality. Canopy cover was positively correlated (p<0.05) with DO and negatively correlated with nitrate (NO3- ) (p<0.05). Quantitative as well as qualitative hydrological differences was observed between these watersheds. The physico-chemical parameters of stream water like Dissolved oxygen, Electrical conductivity, Water temperature, Nitrate was found to be influenced by canopy closure of watersheds. The Canopy closure was significantly and positively correlated with soil water holding capacity, soil moisture and soil organic carbon. Soil water holding capacity was found to be significantly and positively correlated with soil porosity, soil moisture soil organic carbon and negatively correlated with soil bulk density. 119 Soil porosity was positively correlated with soil moisture and soil organic carbon and negatively correlated with soil bulk density. Soil moisture was positively correlated with the soil organic carbon and negatively with soil bulk density. Soil bulk density was negatively correlated with the soil organic carbon More extensive study covering a range of added parameters should be conducted to understand the function of different forest ecosystems in maintaining hydrological processes. The hydrological characteristics should be researched for two or more annual cycles to get a comprehensive understanding. The results of this study also point to an imperative necessity of longer duration studies covering (premonsoon, monsoon, and post-monsoon) seasons for more complete view of the hydrological functions of a forest watershed.ThesisItem Open Access Analysis of urban microclimates (UMCs) in Thrissur corporation using micro meteorological measurements and remote sensing data(Department of Natural Resource Management, College of Forestry,Vellanikkara, 2022-10-12) Mamatha, N A; KAU; Gopakumar, SGlobal urban population is increasing at an alarming rate. Unplanned and inadequately managed urbanization has profound effects on microclimate. The unplanned urbanization could transform cities and townships into urban heat islands (UHI) one of the most evident climatic modifications in urbanized areas. The increased heat in the cities affect the environment and the thermal comfort of organisms. Understanding the urban climate is very necessary to make the cities sustainable. The objective of this study is to investigate and analyse the urban microclimates in Thrissur Corporation limits and to understand their linkages with urban greenery. This study will also examine and analyse the perceptions of urban residents in the study locations about different aspects of climate change. The LULC map of Thrissur Corporation was prepared based on NRC guidelines in ArcGIS using Landsat 8 satellite data acquired from Earth Explorer. Three urban LULC class were selected to take the in-situ temperature measurement. Ambient air temperature and relative humidity were measured during the study period in morning 7.30 am and afternoon 2.30pm, the data is further used to assessing urban heat island intensity. Highest temperature was recorded from LULC urban compact, that constitute the commercial center of the city, where the region occupied by highly dense buildings, dense population, heavy traffic, pavement and other impervious structures. The temperature recorded from other urban LULC classes such as urban_sparse and urban- _vegetation is comparatively low. The least temperature was recorded from urban_vegetation. It was noted that temperature difference between LULC classes such as urban_compact, urban_sparse and urban_vegetation is prominent during afternoon compared to morning air temperature. The urban heat island intensity ranging between 0ºC -5.53ºC was observed in LULC class urban_compact. Land surface temperature (LST) and normalized difference vegetation index (NDVI) of various LULC classes in Thrissur corporation was estimated and it was found that the LST is maximum in the LULC urban_compact, where the NDVI values are minimum. Whereas the LST is minimum in the LULC cropland_paddy where the NDVI is maximum. Among the three urban classes, viz. the urban_compact, urban_sparse and urban_vegetated the minimum LST was estimated in the LULC urban_vegetated. To understand the linkage between microclimate and urban greenery correlation test was done between the LST and NDVI values estimated in various urban LULC classes. A strong negative correlation was observed in LULC urban_vegetated (-0.35). The correlation coefficient estimated in urban_sparse and urban_compact is - 0.46 and -0.41 respectively. A perception study was done among 30 people residing in urban area. The way people think about climate change is crucial to developing strategies to address the problem. Among the respondents, majority (80%) have the opinion that the human interventions, predominantly deforestation are the major cause of climate change. On the other hand, 20 % of the respondents are not sure whether human interventions only causes climate change or any natural causes are also there. Chi-square test was done to find the association of respondent’s age and gender with their perception on various aspects of climate change, and no association was found between the respondents age and gender with their perception on climate change. From the study it was understood that the UHI has been developed in the core of Thrissur muncipal corporation belongs to LULC class urban_compact that includes places like East fort, High road and North bus stand. The study also observed the role of urban vegetation in mitigating the urbanization induced climatic modification. However a more focused study considering extra parameter such as air quality , wind speed and wind direction etc will give a better understanding of UMC. In the wake of rapid urbanization UMC study would be helpful in modelling cities for sustainable development.ThesisItem Open Access Air Layering in selected fruit crops influenced by medium fortified with root colonizing fungi(Department of Agricultural Microbiology, College of Agriculture, Vellayani, 2023-02-15) Sangeetha Lakshmi, B; KAU; Chitra, NThe study entitled “Air layering in selected fruit crops influenced by medium fortified with root colonizing fungi” was conducted at the Department of Agricultural Microbiology, College of Agriculture, Vellayani during the period 2020-2022. The objective of the study was to investigate the effectiveness of air layering medium fortified with Piriformospora indica and/or Glomus fasciculatum on rooting and the establishment of layers of selected fruit crops. An initial experiment was conducted to evaluate the survival of the root colonizing fungi in air layering medium. The tomato seedlings planted in this medium showed root colonization with Piriformospora indica and/or Glomus fasciculatum showed colonization at 4 and 6 weeks after planting confirming that the fungi survive in the medium. Significant increase in IAA production was observed in tomato seedlings grown in layering medium individually inoculated with AMF and P. indica. Fruit crops viz., Guava, West Indian Cherry and Rambutan having varying percentage of rooting and establishment on air layering were selected for the study. The air layering medium fortified with Piriformospora indica (1% w/v), Glomus fasciculatum (5% w/v), combination of Piriformospora indica and Glomus fasciculatum, and IBA (1000 ppm) were used along with a control. Air-layering experiment with different treatments in Guava showed significantly higher root fresh weight and dry weight in combined inoculation of AMF and P. indica which was comparable to IBA treatment. On propagation of successful layer in polybags it was noted that the root volume of guava plants raised in laying medium fortified with P. indica, IBA and AMF (20.2,19.6 and 17.28 cm3 , respectively) were statistically on par and significantly higher compared to other treatments. Guava plants grown in air layering medium fortified with P. indica recorded the highest root fresh weight and dry weight (7.726 g and 2.49 g respectively). On observation of root colonization of fungi, it was seen that P. indica colonized only in the inoculated plants and but native AMF was found to colonize all guava plants. In similar studies in West Indian Cherry, layers grown in G. fasciculatum fortified medium recorded the highest number of primary roots, root volume (0.42 cm3 ), root fresh weight (0.406 g) and root dry weight (0.04 g). Treatment with IBA was on par with AMF treatment in the number of roots and root fresh weight. The percentage of successful layers was significantly high in the treatment combination of P. indica and AMF (86 percent). In in vivo study on establishment of rooted layers of West Indian Cherry planted in polybags, shoot length (67.4 cm), root length (51.2 cm), root volume (25.6 cm3 ), shoot fresh weight (27.666 g), dry weight (17.326 g), root fresh weight (8.26 g) and dry weight (3.956 g) were significantly higher in plants grown in air layering medium fortified with P. indica when compared to control. As in the case of Guava plants, West Indian Cherry also showed colonization by native AMF even in control plants but P. indica colonization was observed only in P. indica inoculated plants. The same sets of experiments in Rambutan revealed induction of callus formation in the wounded region two months after layering and rooting three months after air layering in medium fortified with P. indica and G. fasciculatum. Even though there was rooting, the number of successful layers were less and those rooted layers, when planted in the polybags for further study, dried off. Results of the present study suggest that fortification of air layering medium with root colonizing fungi viz., Piriformospora indica and Glomus fasciculatum can improve rooting and establishment of layers in Guava and West Indian cherry and the results are comparable to that of IBA treatment at 1000 ppmThesisItem Open Access Development and performance evaluation of vertical farming structures in rainshelter(Department of Irrigation and Drainage Engineering, Kelappaji College of Agricultural Engineering and Technology , Tavanur, 2022-04-02) Gopika, P.; KAU; Anu, VarugheseA study was conducted to develop a vertical farming structure suitable for rainshelters for homestead cultivation of Kerala and to evaluate the performance of the developed structure. The newly designed and fabricated Vertical Farming Structure (VFS I) was compared with two existing structures, viz, VFS II and VFS III. Amaranthus of CO-1 variety was selected for the study. Combination of Sand: Soil: Cowdung: Vermicompost in the ratio 1: ½: 1: ½ respectively on volume basis was selected as the growing media. Irrigation was provided through drip irrigation. The performance of the vertical farming structures was compared by assessing the climatic parameters (temperature, RH, light intensity and PAR) and biometric observations (height and number of branches) and yield. Maximum temperature (37.28°C) was recorded during 1:00 PM and lower temperature (24.1°C) was recorded during early morning hours. Higher relative humidity (98.9%) was recorded during early morning hours and lower relative humidity (50.59%) was recorded during afternoon hours. Light intensity and PAR were maximum in VFS I (49000 lux and 1032 µmol m-2 s-1) followed by VFS II and VFS III respectively. Statistical analysis was done by twoway Analysis of Variance (ANOVA) with replications using SPSS 16.0. The results from statistical analysis showed that the light intensity and PAR at 8:00 AM, 1:00 PM and yield per plant showed a significant difference between the structures and tiers individually and also in combination at 5% level of significance. Light intensity and PAR at 5:00 PM, height and number of branches significantly varied between structure and tier individually. Maximum B-C ratio of 1.33 was obtained for VFS I, followed by 1.19 and 1.13 for VFS II and VFS III respectively. The positive values of NPW in all the three cases indicated that the project is viable. The overall results of the study revealed that the VFS I showed better performance in all aspects compared to VFS II and VFS III. The study recommended rainshelter cultivation of vegetables with facility for utilising vertical space using the vertical farming structure and drip irrigation. The developed structure is suitable for increasing the production from the homesteads of Kerala.ThesisItem Open Access Soil carbon stocks and their thermal stability in the agroforestry systems of manali watershed,Thrissur(College of Climate Change and Environmental Science, Vellanikkara, 2023) Nimisha, P H; Sandeep , S; KAUDepletion of SOC pools has a detrimental effect on soil quality, biomass productivity, and water quality, and the problem could get worse due to projected global warming. Agroforestry can act as a potential mitigative measure to cope up with the adverse effects of climate change. In Kerala, an agroforestry technique based on integrated coconut farming has traditionally shown promise in homegardens. Homegarden study focuses on coconut-based agroforestry systems, evaluating carbon storage capacities across three home garden sizes (small homegarden is <0.2 ha, medium homegarden 0.2-0.4 ha, large homegarden >0.4 ha). In these HGs, the carbon stock and soil organic carbon at various soil depths were examined. The selected homegardens were in Manali watershed region in Thrissur district. The soil properties or carbon stocks didn’t vary significantly between the three home garden systems. However, the amount of carbon stored in the different sized aggregates were found to vary between the systems and with depth in each system. Finest fraction (<0.2mm) stores more carbon. Though having similar carbon stocks, the carbon decomposition rate was lowest and activation energy maximum in small home gardens indicating that carbon in these systems were comparatively stable than the other studied systems under future rises in temperature. Agroforestry has bright future possibilities due to growing acknowledgement of its value in promoting sustainable agriculture and mitigating climate change. Future agricultural and environmental policies must include agroforestry because it may boost biodiversity, reduce carbon emissions, and improve food security.ThesisItem Open Access Diversity analysis of chittamruthu [Tinospora cordifolia (WILLD.)] accessions from the northern districts of Kerala(Department of Plantation Crops and Spices, College of Agriculture, Vellayani, 2023-02-10) Dhanya, T; KAU; Sonia, N SThe present investigation entitled “Diversity analysis of Chittamruthu [Tinospora cordifolia (Willd.)] accessions from the Northern districts of Kerala” was carried out in the Department of Plantation Crops and Spices, College of Agriculture, Vellayani during the period 2020-2022 with the objectives to estimate the genetic variation in Chittamruthu accessions using SSR markers and its phytochemical screening. Chittamruthu plant samples (25 nos.) were identified and collected from 25 different locations in the 13 Agro-Ecological Units (AEUs) of North Kerala viz., AEU 2 [Mundayad, Kannur and Elathur, Kozhikode], AEU 6 [Thavanoor, Malapuram and Iringalakkuda, Thrissur], AEU 7 [Cherukunnu, Kannur and Pilicode, Kasaragod], AEU 10 [Chelakkara, Thrissur and Madakkathara, Thrissur], AEU 11 [Kakkodi, Kozhikode and Elamkulam, Malappuram], AEU 13 [Nilamboor, Malapuram and Peravoor, Kannur], AEU 15 [Kelakam, Kannur and Kottiyoor, Kannur], AEU 18 [Attapadi, Palakkad and Sholayur, Palakkad], AEU 19 [Attapadi, Palakkad and Pudur, Palakkad], AEU 20 [Ambalavayal, Wayanad and Kalpatta, Wayanad], AEU 21 [Pulpalli, Wayanad and Thirunelli, Wayanad], AEU 22 [Puthuppariyaram, Palakkad and Vadakkancherry, Palakkad] and AEU 23 [Pattancherry, Palakkad]. The indigenous traditional uses of Chittamruthu plants documented through a survey done in these locations are as follows. The plant could cure cough and cold, acts as an anti-arthritis agent, a remedy for headache, treatment for indigestion and constipation, cure skin issues, cure fever, relieve pain and inflammation in joints, cure for urinary infection, treating diabetes, remedy for piles, control complications of dengue fever, control the risk of cardio- vascular disorders and used as a liver tonic. Morphological diversity analysis of Chittamruthu accessions had identified a superior accession from North Kerala viz., accession 1 (T1) from Mundayad- Kannur (AEU 2) possessing significantly higher stem diameter (1.93 cm), density of lenticels (141.33 no.s), leaf petiole length (11.13 cm), laminar length (11.07 cm), laminar breadth (12.03 cm) and leaf area (117.67 cm2 ). Molecular diversity analysis of Chittamruthu accessions were carried out using 10 SSR primers. Among them, four primers viz., TCTSSR 104, TCTSSR 92, TCTSSR126 and TCTSSR-59 found to be polymorphic in nature. The primer TCTSSR 104 was found to be more informative for diversity analysis since, it has got higher polymorphism information content (PIC) value, 0.46. The dendrogram obtained from polymorphic SSR markers using NTSYS-pc software had grouped the 25 Chittamruthu accessions into four major clusters. Cluster I and II included two accessions, cluster Ⅲ contained three accessions and cluster Ⅳ was the largest cluster containing total of 18 accessions. There exists phytochemical diversity among the 25 Chittamruthu accessions. Qualitative analysis of Chittamruthu accessions exhibited the presence of alkaloids, flavonoids, phenols, saponins and cardiac glycosides. Quantitative phytochemical analysis revealed that T3, the accession obtained from Thavanoor, Malappuram (AEU 6) recorded the highest total alkaloid (102.89 µg AE mg-1 ), total flavonoid (54.29 µg QE mg-1 ), total phenol content (116.54 µg GAE mg-1 ) and cardiac glycosides (25.87 µg DE mg-1 ). Total saponins were found to be high (72.84 µg DE mg -1 ) in the accession, T13 obtained from Kelakam, Kannur (AEU 15). The study revealed that Chittamruthu accessions collected from 13 different AEUs of Northern districts of Kerala were found to be diverse in morphological, molecular and phytochemical characteristics. The accession collected from Mundayad, Kannur (AEU 2) found to possess superior morphological parameters and accession collected from Thavanoor, Malappuram (AEU 6) found to be superior in phytochemical quality. In addition, the Chittamruthu accessions collected from different AEU’s of Northern Kerala could be clustered into four main clusters based on molecular diversity.ThesisItem Open Access Studies on the growth and propagation of selected bamboos in Kerala, India(Department of Silviculture and Agroforestry, College of Forestry, Vellanikkara, 2024-04-30) Amani Khalil Alahmad; KAU; T K KunhamuWith the increasing demand for wood and wood products, tree plantation activities are expanding at faster rate across the world. The present scenario demand planting of tree species that offer better economic returns while contributing to the ecological resilience of the agroecosystems. In this pursuit, bamboos are excellent group of plants that serve the dual purpose effectively. Bamboos are the arborescent grasses belonging to family Poaceae. India is the second richest country of bamboo genetic resources after China. Kerala is one among the major diversity centers of bamboo in the country and 22 species of bamboos under seven genera have been recorded from this region. In Kerala bamboo grows in forests and agroecosystems. The edaphic and climatic conditions of Kerala permit the cultivation of diverse species of bamboos. Though bamboos exhibit fast growth, it varies considerably with species and local conditions. However, information on the productivity of bamboo especially in the humid tropical conditions of Kerala are limited. In this backdrop a field study has been designed to evaluate the comparative growth performance of six bamboo species of high economic and ecological importance to Kerala viz. Bambusa balcooa, Bambusa tulda, Bambusa vulgaris, Dendrocalamus asper, Dendrocalamus brandisii, Dendrocalamus longispathus. The study also probed into the suitable vegetative propagation techniques for selected three bamboo species Dendrocalamus longispathus, Dendrocalamus brandisii, Bambusa balcooa. The field trial was carried out in an existing bambusetum established during 2018 located in Instructional Farm adjoining the College of Forestry campus, Vellanikkara, Kerala, India. Each of the selected six bamboo species were grown in randomly allocated blocks. There were 20 clumps per block at a spacing of 5x5 m. Periodic growth observations were made for clump height, clump circumference, culm girth, intermodal length, and number of culms. Propagation trial was carried out in the nursery separately for the three selected bamboo species viz. Bambusa balcooa, Dendrocalamus brandisii and Dendrocalamus longipathus treating their culm cuttings with various concentrations of NAA and IBA. The experiment was laid out in factorial CRD with three replications. The hormonal combinations were 0, 100, 250 and 500 ppm of both NAA and IBA which were tried separately for the three bamboo species. The hormone treated culm cuttings were planted in nursery beds and all routine observations were taken. There was considerable variation in growth and productivity among the six bamboo species under study. Bambusa vulgaris and Dendrocalamus brandisii were the toppers in terms of clump height, clump circumference and culm girth while Bambusa tulda showed relatively poor growth for these parameters. Among the species, the highest internodal length was observed for by Dendrocalamus brandisii and Dendrocalamus longispathus while Bambusa tulda recorded the shortest internodal length. Number of culms per clump was highest for Dendrocalamus asper while it was the lowest for Bambusa balcooa. Overall, among the six species under study, the promising bamboo for humid Kerala would be Bambusa vulgaris, Dendrocalamus brandisii and Dendrocalamus asper. Among the bamboos, the growth hormonal effects were highest for Dendrocalamus longispathus followed by Bambusa balcooa and the lowest for Dendrocalamus brandissi. Hormonal treated culm cuttings of Dendrocalamus longispathus showed significant improvement in plant height, leaf number, number of roots, root length and rooting percentage while the performance was poor in the untreated control. In general, IBA showed significantly better response to plant height, leaf number and rooting percentage for D. longispathus. Dendrocalamus brandissi showed poor performance for most of the growth parameters except for root weight. However, apparently better response were observed for sporting percentage and rooting percentage with IBA at 250 ppm. The response of untreated control was very poor. Bambusa balcooa showed significantly better performance for NAA for number of leaves (250 ppm), number of roots (250 ppm) and root weight (100 ppm). IBA 250 ppm showed better influence on collar girth and root length of B. balcooa non treated cuttings (control) showed very poor response to all growth parameters. Overall, the propagation study reveals that growth hormonal treatment of culm cuttings of Dendrocalamus longispathus and Bambusa balcooa give promising results for their mass multiplication in nursery conditions.ThesisItem Open Access Evaluation of sponge gourd genotypes for variability and quality(Department of Vegetable Science, College of Agriculture, Vellanikkara, 2023-01-25) Kousthubha, V P; KAU; Anitha, PSponge gourd [Luffa cylindrica (L.) Roem syn L. aegyptiaca Mill] is a summer season vegetable which requires warm summer temperatures. It is an annual climber that yields fruit with a fibrous vascular system. Young fruits are edible, and mature fibres have industrial applications. Potential applications of this crop may literally be seen everywhere in fields including agriculture, medicine, science, engineering, and biotechnology. Even though it has many medicinal and industrial applications, its cultivation is restricted to a limited area. Thus, there is a huge scope to expand its cultivation to non- conventional areas. Since, it is an underutilized vegetable in Kerala, it is very important to have knowledge on genetic diversity of the crop in formulating crop improvement program. In this context, the present study was undertaken with the objectives of determining the genetic variability, correlation between yield and its components, and genetic divergence among sponge gourd accessions, as well as evaluating their quality. The experiment was carried out in Department of Vegetable Science, College of Agriculture, Vellanikkara during February 2022 – June 2022. Wide variability was observed for the morphological characteristics of the sponge gourd accessions. Fruit colour varied from light green to dark green. Accessions IC-343160, IC-332319, IC-284881, IC-313018, IC-312949, Kashi Shreya, and the local collection showed a dark green colour with white stripes. Fruit shaped varied from elongate to elliptical among all the genotypes. IC-334305, IC-284946, and IC-433702 were elliptical in shape. The analysis of variance of the 20 genotypes of sponge gourd exhibited significant differences among them for all the traits under study. Genetic parameters like GCV, PCV, heritability and GAM were estimated to study the degree of variability. High GCV and PCV were exhibited by the characters like node number of first staminate flower, number of primary branches per plant, number of fruits per plant, fruit yield per plant, calcium content, iron content, and fibre content, which implies the presence of a broad genetic base and will be useful in further selection. High heritability coupled with high genetic advance was reported in most of the morphological and quality characters indicating that these characters are under the influence of additive gene action. Fruit yield per plant was significantly and positively correlated with number of primary branches per plant, fruit length, average fruit weight and number of fruits per plant, fibre content and shelf life. Therefore, simultaneous selection for these traits would be useful in improving the yield of sponge gourd. Path coefficient analysis between yield and its component traits revealed that number of fruits per plant, days to first marketable fruit harvest, average fruit weight, days to anthesis of first pistillate flower, number of primary branches per plant, node number of first pistillate flower and rind thickness exhibited direct positive effect on yield. Hence, direct selection for these traits would be useful to improve the fruit yield. From the present study, based on the above traits, accessions IC-343160, IC-332319, IC-312949, IC-343162 and IC-398587 were found good. The 20 sponge gourd genotypes were grouped into seven clusters based on Mahalanobis D2 statistic. Cluster VII had highest number of genotypes (5) followed by cluster VI (4). Cluster I and III had three genotypes each. There were two genotypes in each of clusters IV and V and one genotype in cluster II. Intra cluster distance was maximum in cluster VII. Inter cluster distance was maximum between cluster I and III. Therefore, in hybridization program, genotypes should be selected from these two clusters for developing hybrids. Sensory evaluation was conducted on the cooked as well as uncooked fruits in order to score them based on their appearance, colour, flavour, texture and overall acceptability. IC-312949, IC-343160, IC-332319, IC-284881 and IC-398579 were superior in sensory qualities. There was no bitterness in most of the accessions. The analysis of cucurbitacin E was done using HPLC, and the results showed that cucurbitacin E is absent in all the samples of sponge gourd. The selection index for sponge gourd was fixed by taking the characters like fruit yield per plant, number of fruits per plant, average fruit weight, days to anthesis of the first pistillate flower, and overall acceptability of sensory evaluation and the accessions IC-343160, IC-332319, IC-312949, IC-284869, and Kashi Shreya were identified as the best ones. Genotypes IC-343160, IC-332319, IC-312949 outperformed the released variety Kashi Shreya of IIVR, Varanasi, with respect to yield and quality.ThesisItem Open Access Physiological, biochemical and yield attributes of bell pepper (Capsicum annum var.grossum) as influenced by biochar amended with biofertilizers(Department of Plant Physiology, College of Agriculture, Vellayani, 2023) Simhi Samyukta, S M; Viji , M M; KAUThe programme entitled “Physiological, biochemical and yield attributes of bell pepper (Capsicum annuum var. grossum) as influenced by biochar amended with biofertilizers” was carried out at the Department of Plant Physiology, College of Agriculture, Vellayani during 2021-2022. The objective of the programme was to evaluate the physiological, biochemical and yield attributes of bell pepper as influenced by biochar amended with biofertilizers. A pot culture study was carried out with bell pepper variety “California Wonder” in completely randomized design (CRD). It involved a combination of eight treatments which is inclusive of a control also, with three replications in each. The different treatments were T1-control, T2-biochar, T3-Azospirillum, T4-VAM, T5-Piriformospora indica, T6-biochar + Azospirillum, T7-biochar + VAM and T8-biochar + P. indica. Different morphophysiological parameters like plant height, number of branches, photosynthetic rate, transpiration rate, chlorophyll content, leaf area index, root weight, root volume, shoot weight, root:shoot ratio, days to first flowering and days to first fruiting were studied. Of all the eight treatments that were studied, biochar + VAM (T7) was found to be the best treatment in increasing the morphophysiological parameters. Biochar + Azospirillum (T6) was observed to be on par with biochar + VAM (T7) in terms of photosynthetic rate, transpiration rate, leaf area index and shoot weight. Whereas, P. indica treated plants were found to be on par with biochar + VAM (T7) in terms of root characteristics. Also, P. indica proved to reduce the vegetative period and induce earliness of flowering in bell pepper plants. Considering the biochemical parameters, flavonoid content, total soluble proteins and ascorbic acid content were found to increase under the influence of Azospirillum. Polyphenol content was found to increase upon the treatment with VAM. However, with the application of biochar there was enhancement in all the biochemical parameters, viz. biochar + Azospirillum (T6) proving to be the best in terms of flavonoids (4.87 mg g-1), total soluble proteins (23.67 mg g-1) and ascorbic acid content (129.92 mg 100g-1) while biochar + VAM (T7) in terms of polyphenols (24.34 mg g-1). 104 VAM and Azospirillum were found to be on par with each other in terms of yield parameters, viz. number of fruits per plant, fruit weight and yield per plant. However, among all the treatments, biochar + VAM (T7) resulted in higher number of fruits per plant (7.33), fruit weight (76.42 g) and yield per plant (0.61 kg). Biochar + Azospirillum (T6) was found to be on par with biochar + VAM (T7) pertaining to fruit weight (74.72 g). Among the biofertilizer treatments, nitrogen uptake by the crop was found to be significantly higher in Azospirillum (T3) while phosphorous and potassium uptakes were found to be higher in VAM (T4). Of all the eight treatments, biochar + Azospirillum (T6) recorded the highest nitrogen uptake (131.47 kg ha-1). Biochar + VAM (T7) recorded the highest phosphorous uptake (30.97 kg ha-1) by the crop and was significantly on par with VAM (T4). Also, biochar + VAM (T7) recorded highest potassium uptake (121.60 kg ha-1) which was significantly on par with biochar + Azospirillum (T6). VAM was found to increase the organic carbon content of soil to a higher extent than other biofertilizers. Biochar amendment (T2) significantly recorded highest organic carbon content in the soil (2.99%). Microbial characteristics study also evidently proved that biochar increased the Azospirillum population (40-40.74%) in rhizosphere soil and VAM colonization percentage (5.88-7.5%) in root bits of bell pepper plants when compared to sole application of biofertilizers alone. Based on the present study, it can be concluded that combined application of biochar and VAM biofertilizer could increase the performance of bell pepper plants and improve its physiological, biochemical and yield attributes while also improving the soil organic carbon content and microbial density.
