1. KAUTIR (Kerala Agricultural University Theses Information and Retrieval)
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Item Mango varietal response to Anthracnose disease and its post-harvest management(Department of Plant Pathology, College of Agriculture , Vellayanikkara, 2025-02-15) Nikiru Lamare.; Radhakrishnan, N VThe study entitled “Mango varietal response to anthracnose disease and its post-harvest management” was done to evaluate the incidence and severity of anthracnose in different mango varieties during post-harvest storage and assess the efficacy of certain post-harvest management techniques controlling anthracnose on the quality of fruits in different mango varieties. A survey was conducted in two agro-ecological units – 1 (Southern coastal plain) and 8 (Southern laterites) covering Kollam and Thiruvananthapuram districts. Mango varieties with anthracnose symptoms were collected from the surveyed locations, and pathogen isolates were obtained. The isolates were subjected to pathogenicity testing, morphological characterization, and virulence rating. The cultural and morphological studies showed that isolates displayed fluffy or sparse mycelial growth with white to grey pigmentation and had regular margins. The conidia of all isolates were oblong, dumbbell shaped, measuring 9.2 × 3.5 to 11.4 × 3.6 μm. Upon artificial inoculation on the fruits, the isolates showed the typical anthracnose symptoms, with black or brown sunken lesions. Upon virulent rating, it was revealed that isolate C10 proved to be the most virulent, with a lesion development rate of 1.30 cm/day and PDI of 46.67%. The virulent isolate was molecularly characterized with ITS primers and confirmed as Colletotrichum gloeosporioides (accession no. PQ475860) by phylogenetic analysis. Five mango varieties, Kottukonam, Neelum, Priyur, Rumani, and Totapuri, were obtained and subjected to screening by artificial inoculation of the anthracnose pathogen and assessed the varietal variation in symptom development, lesion growth and susceptibility. Symptoms were developed in 2 days for Kottukonam and Priyur, while Neelum, Rumani, and Totapuri showed symptoms after 3 days. Kottukonam showed the highest susceptibility with a PDI of 72.33%, while Totapuri had the lowest at 45.40%. In vitro evaluation of the antagonistic potential post-harvest management strategies against anthracnose pathogens was studied. Two bacterial cultures of Bacillus velezensis PCSE-10 and B. amyloliquifaciens VLY24 were obtained from the Department of Agricultural Microbiology. The dual culture assay of the biocontrol agents against the anthracnose pathogen revealed that B. amyloliquifaciens VLY24 showed 37.08% inhibition, while B. velezensis PCSE-10 had 32.87% inhibition. Poisoned food assay of carbendazim 50% WP against the pathogen revealed that 0.1% and 0.2% concentration showed 100% inhibition while 0.05% showed 76.67% inhibition. In vitro evaluation of bacterial suspension and cell free culture filtrate (CFC) of biocontrol agents against the pathogen mycelial growth at different concentrations showed that bacterial suspensions were more effective than CFC. In both the strains highest inhibition of mycelial growth was shown in the bacterial suspension of 100% concentration with 78.78% inhibition with B. amyloliquifaciens VLY24 and 76.83% inhibition with B. velezensis PCSE-10. The evaluation of various post-harvest management strategies for controlling anthracnose disease was conducted in five mango varieties in a two-factorial Completely Randomized Design (CRD). It revealed that the combination of hot water treatment (HWT) (52°C for 10 minutes) + B. amyloliquefaciens VLY24 (BA VLY24) (100% suspension) and carbendazim (CBZ) (0.1%) resulted in the lowest per cent disease index (PDI) of 17.04%, followed by the combination of HWT (52°C for 10 minutes) + B. velezensis PCSE-10 (BV PCSE-10) (100% suspension) + CBZ (0.1%), which had a PDI of 18.68%. Among the varieties, the lowest PDI was observed in Totapuri (38.26%), while the highest was recorded in Kottukonam (46.56%). Regarding total soluble solids (TSS), the combination of HWT+ BA VLY24 + CBZ recorded the lowest TSS content (12.86 °Brix). Across varieties, Priyur exhibited the highest TSS content (17.63 °Brix), followed by Neelum (14.65 °Brix). The effects of the interaction of treatments on lesion size and PDI across all varieties were not significantly different, which implies that treatments applied across all varieties have the same relative effect, whereas the impact on TSS varied significantly among varieties as TSS content varies with varieties. A combination treatment of hot water (52°C for 10 minutes) +B. amyloliquefaciens VLY24 (100% bacterial suspension) + Carbendazim 50% WP (0.1%) was applied to five mango varieties (Kottukonam, Neelum, Priyur, Rumani, and Totapuri). The response of treated fruits was compared with untreated controls. On the 7DAI, no symptoms were observed in treated fruits except for Kottukonam, whereas untreated fruits displayed symptoms as early as the 4th or 5th day. PDI was significantly higher in untreated fruits, with the highest PDI recorded in untreated Kottukonam (50.67%) and the lowest in untreated Totapuri (22%). Biochemical analysis revealed that peroxidase and polyphenol oxidase activities were higher in treated fruits than untreated ones on the 7 DAI. Treated fruits also exhibited an extended shelf life, and Totapuri recorded the longest duration (9.33 days). Physiological loss of weight was higher in untreated fruits than in treated fruits. Sensory evaluation revealed that treated fruits exhibited superior internal and external sensory quality in terms of appearance, colour, flavour, and overall acceptability. Among the varieties, Totapuri received the highest overall acceptability score of 8.08. Biochemical assessments indicated that treated fruits had higher titratable acidity whereas, total soluble solids (TSS) and reducing sugar content were lower in treated fruits across all varieties tested. This study concluded that C. gloeosporioides was the pathogen responsible for mango anthracnose. Among the varieties, when subjected to screening by artificial inoculation, it revealed that Kottukonam was the most susceptible mango variety, followed by Priyur, while Totapuri was the least susceptible, followed by Rumani and Neelum. Effective post-harvest management of mango anthracnose can be achieved using a combination of hot water treatment (52°C for 10 minutes), B. amyloliquefaciens VLY24 (100% suspension), and carbendazim 50% WP (0.1%).Item Physiochemical variations in different phenophases of fruit development and value addition in kokum (Garcinia indica (Thouars) Choisy)(Department of Postharvest Management, College of Agriculture , Vellanikkara, 2023-05-31) Sandhya ,Y S; Vikram , H CKokum is an important indigenous, underutilized fruit cum spice crop that originated in the Western Ghats of India. It belongs to the family Clusiaceae (Syn. Guttiferae). Locally, the fruit is called Birand (Konkani), Murugalu (Kannada), or Punarpuli (Malayalam) and is known as the "cool king" of Indian fruits. The rich bioactive profile of kokum makes it an ideal choice in healthy diets and the fruit is mainly used for culinary purposes. The shelf life of the fruit is about one week. The quality of kokum products and the shelf life of fruits are known to be influenced by several physiochemical changes during the fruit growth period. Hence, it is vital to study the physical and chemical changes during the fruit development to facilitate adopting strategies that address problems related to fruit management, harvest, quality, and preservation. In this context, the study was conducted in two experiments: physiochemical changes in different phenological growth stages of kokum fruit and the development of value-added products from kokum. The first experiment evaluated physiochemical characteristics and organic acids at eight stages of fruit growth, development and maturity. Significant variation was observed in the physical properties at all the stages of fruit development in both genotypes. The fruit weight increased from 1.86g (P1) to 29.51g (P8). The maximum fruit breadth was at stage P8 (3.61 cm). The fruit length (0.60 cm) was minimum at the fruit set stage (P1) and increased significantly to 3.27 cm at stage P8. The fresh rind weight gradually increased from the fruit set (P1) to the final stage of harvest (P8). The maximum fresh rind weight was at stage P8 (13.39 g), whereas the dried rind weight was at stage P7 (1.86 g). Rind thickness gradually increased from 0.20 mm (P1) to 2.41 mm (P7). The rind percentage gradually increased from stages P1 (19%) to P8 (45.28%). The sour genotype was superior in all the parameters when compared to sweet genotype. Significant differences were also observed in the chemical properties, such as moisture, acidity, TSS, total sugars, ascorbic acid, anthocyanin, and total phenols in the different phenological stages (P1-P8) of kokum fruit in both the genotypes. The main fruit quality characteristics, such as the total soluble solids (11.08 ºBrix), total sugars (6.58%), and TSS: acidity ratio (3.04), were the highest at stage P8. At the same time, ascorbic acid (39.34 mg/100mg), acidity (6.53%), and total phenols (3.21 mg/g) of the fruit were the highest at stage P1 (fruit set). The moisture content increased from P1 (74.82%) to P8 (80.90%). The anthocyanin content of kokum rind increased from 5.26 (P1) to 23.46 mg/100g (P8) during the development of the fruit. This is the first kind of report on Garcinia indica with respect to organic acid profiling of both sweet and sour genotypes at different phenophases and eleven organic acids were successfully identified and quantified. The content of each organic acid varied significantly from fruit growth to maturity, except for tartaric acid. It was interesting to notice that the levels of hydroxycitric acid (233.16 mg/g), citric acid (107.28 mg/g), malic acid (18.75 mg/g), malonic acid (9.40 mg/g), fumaric acid (0.84 mg/g), and maleic acid (0.58 mg/g) were highest in stage P6. In contrast, the levels of succinic acid (44.24 mg/g), pyruvic acid (8.78 mg/g), and tartaric acid (0.35 mg/g) were highest in the final stage of harvesting, i.e., stage P8, whereas, shikimic acid (0.92 mg/g) and lactic acid (0.22 mg/g) were highest at stages P5 and P7, respectively. In the second experiment, a total of four types of products, viz., kokum carbonated RTS (KCR), kokum non-carbonated RTS (KNCR), kokum groundnut chutney powder (KGCP), and kokum coconut chutney powder (KCCP) were standardized using kokum rind powder. The data of RTS beverages revealed that treatments KNCR4 (15% kokum juice with 15 ºB), and KCR4 (10% kokum juice with 17 ºB) were found superior to all chemical parameters compared to other treatments. In instant chutney powders, KGCP4 (8% kokum powder with 60% roasted groundnut powder) recorded significantly higher total sugars, acidity, and ascorbic acid compared to other treatments of KGCP. Significantly higher total sugars, acidity, total phenols, and antioxidant activity was in KCCP4 (8% kokum powder with 60% roasted coconut powder) than other treatments of KCCP. Among the different treatments of kokum products, the highest organoleptic score was observed in KNCR2 (47.10), KCR3 (50.36), KGCP2 (45.99), and KCCP2 (47.69) in respected products. The products under refrigerated storage were found superior regarding sensory and microbial qualities. The microbial load was within acceptable level in all products made from kokum. The present study revealed that fruits harvested at the final maturity stage (P8) possessed the maximum fruit size, sugars, anthocyanins, lowest acidity, which are essential criteria in determining the maturity of the fruits. Therefore, it is suggested to harvest fruits at their complete maturity stage (P8). Value-added products can be developed from kokum fruit that can be utilized during the off-season. Due to its seasonality, adding value to this fruit will enable consumers to use it throughout the yearItem Assessment of bioactive compounds and product development from major Garcinia spp. of Kerala(Department of Postharvest Management, College of Agriculture,Vellayani, 2023) Aparna, G S; Geetha Lekshmi, P RThe present study entitled “Assessment of bioactive compounds and product development from major Garcinia spp. of Kerala” was carried out in the Department of Postharvest Management, College of Agriculture, Vellayani during 2017-21 with the objective to assess the bioactive compounds in major Garcinia spp. of Kerala viz. G. gummi-gutta (malabar tamarind), G. mangostana (mangosteen), G. xanthochymus (yellow mangosteen) and development of value added products with nutraceutical importance. Primary and secondary metabolites present in pulp and pericarp of the three species were assessed. The G. mangostana recorded highest TSS for pulp as 20.83 0Brix and 27.93 0Brix in pericarp whereas the highest acidity was recorded in Garcinia xanthochymus rind (6.54%) and pulp (6.18%). Mangosteen fruit pulp recorded the highest vitamin C (33.80 mg 100g-1) and total sugar (13.31%) and the yellow mangosteen pulp noticed the highest protein content of 7.24 g 100g-1. Crude fibre (12.37%), fat content (1.35 mg 100g-1), total phenols (2603.68 mg GAE 100g - 1), antioxidant activity (92.27 %), total flavonoids (1.55mg QE g-1), Ca (1910.00 ppm), K (3323.33 ppm) and Fe (9.24 ppm) were found the highest in mangosteen pericarp. Twelve major sugars were quantified from the economic parts of the Garcinia fruits. Garcinia gummi-gutta fruits recorded fructose (8.85±0.028mg g-1) in the highest quantity followed by ribose (4.87±0.019 mg g-1) and glucose (3.14±0.033mg g-1). The prominent sugar was fructose in G. mangostana (28.163±0.813mg g-1) and G. xanthochymus (25.842±0.151 mg g-1). Organic acid profiling of the fruits revealed Hydroxy Citric Acid (HCA) as the major organic acid in G. gummi-gutta fruits (547.458±4.185mg g-1) and citric acid was the most abundant organic acid in G. mangostana (674.17±0.485 mg g-1) and G. xanthochymus fruit (680.361±0.863mg g-1). The phenolic profiling of Garcinia fruits showed p-coumaric acid as the major phenolic acid in G. gummi-gutta (104.81 μgg-1), G. xanthochymus (353.61 μgg- 1) and G. mangostana (335.70 μgg-1). A total of thirteen individual flavonoids were identified and quantified from selected Garcinia fruits and epicatechin (18.699±0.211 μgg-1), catechin (6.688±0.492 μgg-1) and luteolin (8.814±0.791 μgg-1) were the predominant individual flavonoids in G.gummi-gutta. Mangosteen fruit pulp recorded the highest quantity of hespertin (36.980 μgg-1) whereas naringenin (44.424±0.363 μgg-1) was the abundant flavonoids in G. xanthochymus fruits. Natural polyisoprenylated benzophenones such as garcinol and isogarcinol were isolated by column chromatography followed by crystallization from the hexane extract of G. indica fruits. Another benzophenone xanthochymol was isolated by column chromatography using hexane extract of G.xanthochymus fruits. The structural identification of the compounds was done by spectroscopic methods like UV-Vis, 1H NMR and 13C NMR. HPTLC densitometry method was used to compare and quantify the benzophenones in three major Garcinia species. Results showed that garcinol was the major benzophenone in G.gummi-gutta (7.53 %) and G. xanthochymus (8.26%) whereas G.mangostana fruits were high in isogarcinol (8.10%). The major xanthone, α-mangostin was quantified in mangosteen rind as 3.62 % on dry weight basis. The pigment was extracted from dried and powdered pericarp of ripe mangosteen fruits by the method of hot maceration where distilled water (aqueous extraction) and ethanol as solvents, acidified with citric acid (0.1% and 0.2%) and acetic acid (1% and 2%) at different levels. Based on higher extraction yield (28.57%), anthocyanin content (294.73 mg 100 g-1), total phenols (1549.55 mg GAE 100 g-1) and antioxidant activity (82.68%), colour extracted with acidified ethanol (2% acetic acid) was selected as the best solvent system and was further utilized as a natural colourant in Garcinia nectar formulations. For the development of nectar formulations from Garcinia spp., G. gummigutta rind, mangosteen pulp and G. xanthochymus pulp, was used at different fruit pulp concentration (15%, 20%) and TSS (150 Brix, 200 Brix, 250 Brix, 300 Brix). Biochemical quality parameters such as titratable acidity, vitamin C, total sugar, reducing sugar, antioxidant activity, total phenol content, total flavonoids and HCA were analyzed for all nectar formulations. Based on biochemical quality and sensory mean scores of the formulations, G. gummi-gutta nectar prepared with 20 % fruit and 200 Brix, Garcinia mangostana nectar formulation with 20% fruit with TSS 150 Brix and for G. xanthochymus fruit beverage prepared with 15% fruit and 200 Brix were selected as the best formulations for the supplementation of natural colour extracted from mangosteen pericarp. The selected nectar formulation of G. gummi- gutta and G. xanthochymus was added with 0.5% mangosteen pericarp colour extract whereas 0.3 % was added to G. mangostana nectar. Storage stability studies of the nectar formulations were conducted under room temperature along with control (formulation without addition of natural colour). During storage, TSS, titratable acidity, total sugar and reducing sugar parameters of the nectars were increased whereas vitamin C, total phenols and antioxidant activity showed a decreasing trend. The effect of light on colour stability of the nectars was studied and nectar stored in amber bottles retained more anthocyanin than in transparent glass bottles. The temperature stability studies revealed that with the increase in temperature and time, total anthocyanin content of the beverages decreased. Sensory quality analysis of the nectar formulation revealed that beverages added with natural colour extract recorded the highest sensory mean score for colour and overall acceptability without affecting the taste and flavour. Garcinia gummi-gutta fruit rind was utilized for preparation of various valueadded products viz. osmodehydrated rind, culinary paste and pickles. The effect of different osmotic concentrations (500 Brix and 700 Brix) and immersion time (24, 36 and 48 h) on mass transfer characters, and quality parameters of osmodehydrated rind were evaluated. The mass transfer characters viz. solid gain, water loss, and weight reduction were increased with increase in immersion time and osmotic concentration. Osmodehydrated products packaged in polypropylene were stored for a period of 3 months and storage stability studies were conducted. The TSS, acidity and sugars were increased during storage whereas HCA and antioxidant activity decreased. The storage study revealed that osmotic treatment, 700 Brix for 36 h exhibited highest acceptability and used for pickle development studies. The fresh malabar tamarind rind was used for the preparation of culinary paste with different levels of salt concentration (3%, 5%,7%, 9%) and without the addition of salt as control. The moisture content, HCA, and antioxidant activity were decreased meanwhile TSS, total sugar, reducing sugar, acidity and total flavonoids of the paste increased during storage. The paste prepared with 9% salt recorded the lowest browning index (31.52 %), bacterial load and the highest score for taste (8.33), flavour (8.27) and overall acceptability (7.87) after three months of storage. Sweet pickle from osmodehydrated (700Brix for 36 h) slices and sour pickle from fresh G.gummi-gutta rind were prepared and analysed for biochemical, microbial and sensory quality during storage of 2 months. The total sugar, reducing sugar, vitamin C and antioxidant activity of the pickles decreased during storage and both sweet and sour pickles were found acceptable. The major Garcinia spp. viz. G. gummi-gutta (malabar tamarind), G. mangostana (mangosteen), G. xanthochymus (yellow mangosteen) were found rich in bioactive compounds. The anthocyanin colour was effectively extracted from mangosteen pericarp with acidified ethanol and was used as a natural colourant in Garcinia fruit beverages. Value added products viz., osmodehydrated rind, culinary paste, sweet and sour pickles were developed from G. gummi-gutta rind with good acceptability and storage stability.Item Aloe vera based edible film coating for shelf life extension in tomato (solanum iycopersicum)(Department of Post Harvest Technology, College of Agriculture, Vellayani, 2018) Thushara T Chandran; Mini, C