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ThesisItem Open Access Protocol development for gel stabilization and nutraceuticals in aloe vera (L.) Burm. f.(Department of Plantation Crops and Spices, College of Agriculture, Vellayani, 2021) Maheswari R S Nair; KAU; Sreekala, G SThe investigation entitled “Protocol development for gel stabilization and nutraceuticals in Aloe vera (L.) Burm. f.” was carried out in the Department of Plantation Crops and Spices, College of Agriculture, Vellayani during March 2016 to December 2019. The project envisaged formulation of a low cost stabilization technique for aloe gel using herbal extracts and aromatic oils and development of protocols for the preparation of dried latex and marketable nutraceuticals using aloe gel. The study was carried out as four experiments. The first experiment was to study the keeping quality and natural spoilage flora of fresh gel while the second experiment was for the standardization of curacao aloe (dried latex). The third experiment was on gel stabilization using herbal extracts and essential oils. Preparation of nutraceuticals from the stabilized liquidized aloe gel juice was the final experiment. The keeping quality and natural spoilage flora of fresh gel were assessed by subjecting the liquidized aloe gel juice to storage in glass bottles under ambient condition for seven days. The liqudized aloe gel juice was off white in colour for first three days of extraction with mild vegetative odour and got sedimented with foul smell from fourth day onwards. The liquidized aloe juice could not be stored for more than a day due to increased microbial population from the second day of storage. Preliminary trails conducted by pasteurizing the liquidized aloe gel juice at 65 0C and 15 psi pressure for 13 minutes followed by flash cooling registered no microbial population even after seven days of storage. The latex collected from aloe leaves was subjected to different methods of drying such as boiling followed by cooling, sun drying, shade drying and oven drying. Appearance, colour and aloin content (271.62 mg/ml) of dried latex was significantly higher for shade drying. Liquidized aloe gel juice was pasteurized and added with varying concentrations of three forms (aqueous, tincture, decoction) of herbal extracts and essential oils after adjusting the pH to 3.5 by adding 0.5 per cent of citric acid for gel stabilization. The treated samples were kept for a month and based on microbial population and minimum inhibitory concentration best treatment of each form was selected from preliminary trials for aloe gel stabilization. Gymnema sylvestre aqueous extract (1 ml), tincture (1 ml), decoction (2 ml), Centella asiatica aqueous extract (1 ml), tincture (2 ml), decoction (1 ml), Achyranthes aspera aqueous extract (2 ml), tincture (2 ml), decoction (1.50 ml), Tridax procumbens aqueous extract (2 ml), tincture (2 ml) , decoction (1 ml), Terminalia chebula aqueous extract (1 ml), tincture (1 ml), decoction (1 ml), Punica granatum aqueous extract (1 ml), tincture (2 ml), decoction (1 ml), green tea aqueous extract (2 ml), tincture (1 ml) and decotion (2 ml) and 1 ml each of sacred basil oil, lemon grass oil, cinnamon bark oil, clove oil and cardamom oil were selected and added to pH adjusted , pasteurized and liquidized aloe gel juice (25 ml) for gel stabilization. The gel stabilization was thus done using the selected twenty six treatments in a Completely Randomised Design replicated five times and compared with 0.08 per cent sodium benzoate as control and stored for six months. Appearance, colour and odour of all forms of the herbal extracts reduced on storage while those treatments with aromatic oils showed lesser percentage reduction in these parameters. Total solids, amylase and lipase activity decreased on storage. The amino acid content was the highest for liquidized aloe gel juice added with aqueous, tincture and decoction of Achyranthes aspera (0.08 ppm).Vitamin A and C were highest for treatment with green tea leaf aqueous extract which decreased subsequently on storage. An increase in microbial load was observed for all the treatments with herbal extracts from first month of storage. But addition of 1 ml clove oil resulted in stabilization of liquidized aloe gel juice which could be stored upto five months without microbial contamination or affecting the nutritive and sensory parameters. Nutraceuticals were prepared using stabilized liquidized aloe gel juice containing clove oil blended with lemon juice, orange juice and honey in proportions of 50 : 50, 75 : 25 and 90 : 10 followed by pasteurization, flash cooling and stored for 6 months. Appearance, colour and vitamin C were significantly higher for Lemon juice (50 ml) + Liquidized aloe gel juice (50 ml) + 2 ml clove oil while odour, taste, overall acceptability, pH, TSS, carbohydrates and calories were significantly superior for Honey (50 ml) + Liquidized aloe gel juice (50 ml) + 2 ml clove oil. Growth of microbes could be detected from third month of storage for all the treatments. Aloe health drink with honey in the ratio 50 : 50 added with clove oil were selected as the accepted drink which could be preserved for two months without microbial contamination. The preparation of aloe herbal powder by solar drying, air drying, oven drying or freeze drying resulted in a sticky product which could not be reconstituted with distilled water for quality comparison with fresh gel, thus warranting further investigation. The present study revealed that liquidized aloe gel juice pasteurized and mixed with clove oil (4 per cent) is a low cost stabilization method which can be taken as a base material for the preparation of health drink. The nutraceutical with liquidized and stabilized aloe gel juice mixed with equal proportion of honey and preserved with clove oil is a palatable drink having higher calories which could be stored for two months. The dried aloe latex a byproduct produced by shade drying is superior with high aloin content and can also be used for the development of marketable product.ThesisItem Open Access Growth, yield and secondary metabolite production responses to microbial elicitation in Withania somnifera (L.) Dunal(Department of Plantation Crops and Spices, College of Agriculture, Vellayani, 2021) Ragin, Shaji; KAU; Deepa, S NairThe study entitled “Growth, yield and secondary metabolite production responses to microbial elicitation in Withania somnifera (L.) Dunal.” was conducted at the Department of Plantation Crops and Spices, College of Agriculture, Vellayani, Thiruvananthapuram during 2019-2021 with a view to evaluate the effect of bacterial inoculants on seed germination, seedling vigour, growth, yield and secondary metabolite production in W. somnifera. Seeds of W. somnifera were primed with B. amyloliquefaciens (Bam), B. pumilus (Bp) and B. velezensis (Bv) at 1x 108 cfu mL-1 individually and in combination for 24 h. Among these treatments, T7, the trio combination of Bam+Bp+Bv recorded the earliest germination (5.33 days) highest germination per cent (96.67), survival per cent (92.67) seedling vigour index (958.93), basal shoot girth (0.81 cm), number of leaves (6.07), leaf area (13.38 cm2 ), shoot length (5.77cm), root length (4.16 cm) and root volume (0.54 cm3 ). All the biopriming treatments with Bacillus spp. recorded superior germination and seedling parameters over the untreated control (T9) and hydropriming (T8). The seedlings from the first phase were subjected to root dip with the respective bacterial suspension for 30 min on transplanting. The morphological and yield determining parameters such as shoot length(78.99 cm), root length (21.27cm), number of branches (8.78), number of leaves (71.00), collar girth (3.91 cm), leaf area (5146.81 cm2 ) number of flowering branches (7.89), stem fresh weight (61 .85 g plant -1 ), stem dry weight(9.78 g plant -1 ), leaf fresh weight (45.89 g plant -1 ), leaf dry weight (5.07g plant - 1 ), root fresh weight (5.47g plant-1 ), root dry weight (1.44 g plant-1 ) 100 seed weight (0.26g ) root diameter (1.33cm), root volume (5.39 cm3 ) and harvest index (0.10) were observed to be significantly higher in T7, the trio combination of (Bam+ Bp+ Bv), which was observed to be on par with T5, dual combination of (Bam+ Bv). T5 was found to be superior in shoot fresh and dry weight, berry fresh and dry weight, number of berries and 133 seed yield per plant and total dry matter production (97.48, 17.51, 8.85 and 5.32 g plant-1 , 90.56, 7.35, 18.89 g plant-1 respectively, which was observed to be on par with T7. All the said parameters were significantly lower in untreated control. Seedlings treated with bacterial suspension of B. velezensis (Bv) recorded highest chlorophyll content in the leaves of W. somnifera at the time of harvest. The highest total alkaloid content in leaves (7.86 µg 100 mg-1 ) was recorded in dual combination of Bp+Bv which was on par with the other combinantions, Bam+Bv (T5) and Bam+Bp+Bv (T7). T5 recorded the highest protein and carbohydrate content (2.96 and 23.30 mg 100 mg-1 respectively) in the roots which was on par with T7. The withanolide content was superior (7.46 µg mg-1 ) in T7, Bam+Bp+Bv which was on par with T5, Bam+Bv and T6, Bp+Bv. The yield of biochemical parameters on per plant basis viz., total leaf alkaloids, total root withanolides were the highest (397.44 µg plant-1, and 10.77 mg plant-1 respectively) in trio combination of T7 which was on par with dual combination T5. The control treatment recorded significantly lower values in all the biochemical parameters observed. In the first phase of the study, the trio combination of Bam + Bp+ Bv (T7) gave the best performance in terms of seed germination, seedling growth and seedling vigor index, In the second phase, Bam + Bp+ Bv (T7) and Bam+ Bv (T5) gave superior performance, in terms of plant growth, yield and biochemical parameters.ThesisItem Open Access Evaluation of medicinal plant-based formulations for growth, yield and pest management in chilli (Capsicum annuum Linn.)(Department of Plantation Crops and Spices, College of Agriculture, Vellanikkara, 2021) Shafreena Shirin, P; KAU; Lissamma, JosephPest management is one of the important components of crop management to mitigate economic losses of agricultural crops and commodities. The harmful effects of chemical pesticides on environment and health concern have caused a shift to adapt various ecofriendly ways of pest management. Therefore, botanical pesticides are gaining popularity because they are safe to use on crops produced for human consumption and recently there is a lucrative market among consumers willing to pay more for organically produced food. This positive trend has encouraged the research field to focus more on ecofriendly and effective pest management strategies. A study entitled “Evaluation of medicinal plant-based formulations for growth, yield and pest management in Chilli (Capsicum annuum Linn.)” was carried out at the Department of Plantation Crops and Spices, College of Agriculture, Vellanikkara during the period from October 2020 to May 2021 with Chilli variety Anugraha as the test crop. Three medicinal plant based trial products (P1, P2, and P3) and their combinations (P4, P5 and P6), developed and screened at Aromatic and Medicinal Plants Research Station (AMPRS), Odakkali were utilized for the study. P1 was developed from Vayambu (Acorus calamus), P2 from Manja Koova (Curcuma zedoaria), P3 from Erukku (Calotropis gigantea), P4 from Acorus calamus and Curcuma zedoaria, P5 from Curcuma zedoaria and Calotropis gigantea and P6 from Acorus calamus and Calotropis gigantea. Solid soap formulations of these three and their combination were evaluated at one and two per cent concentrations at ten days intervals along with an absolute control (T13- 1% soap solution without any botanicals) and positive control (T14-1% Neem garlic extract). The growth parameters like plant height (cm), leaf length (cm), breadth (cm),and days to 50 per cent flowering and fruiting, yield characters like fruit length (cm) and breadth (cm), fruit weight (g), number of fruits and fresh fruit yield per plant and qualitative characters like Vitamin C (mg 100g-1 ) and oleoresin content (%) were recorded. Statistical comparison of morphological and qualitative parameters under various treatments was done through one-way analysis of variance (ANOVA) using KAU GRAPES software. Effect of spraying the liquid formulations of medicinal plant based products and their combinations against sucking pests like thrips, whitefly and aphids during the experimental period (December, 2020 to May, 2021) were studied. Population density of sucking pests viz. thrips, white fly and aphids were recorded. Data on mean population of sucking pests were tested by analysis of covariance (ANOCOVA) using R studio software, taking population counts prior to the treatments application as covariate. The result obtained was subjected to Duncan’s Multiple Range Test (DMRT) and treatments were analysed. The plant height showed an increasing trend from one month after transplanting to five month after transplanting. The increment in plant height was reduced from three months onwards after attaining the reproductive stage. The maximum cumulative plant height of 61.05 cm was observed in T3 (Calotropis gigantea at 1%) among the treatments.The maximum cumulative leaf length of 5.82 cm was observed in T2 (Curcuma zedoariaat 1%). The maximum cumulative leaf breadth of 2.87cm was observed in T14 (Pest management as per Organic POP). Days to 50 per cent flowering for different treatments varied from 42.66 to 47.66 days. The minimum days to 50 per cent flowering recorded in T5- Curcuma zedoaria at 2 per cent and T6- Calotropis gigantea at 2 per cent. Days to 50 per cent fruiting for different treatments varied from 55 to 62.66 days. Treatment T9- Curcuma zedoaria and Calotropis gigantea at 1 per cent recorded minimum days to 50 per cent fruiting (55 days). Fruit length of chilli variety Anugraha under different treatments varied from 6.13 cm to 6.80cm. The maximum fruit length of 6.8 cm was recorded in T6 (Calotropis gigantea at 2%). Fruit breadth (cm) varied from 2.16 to 2.76 cm. The maximum fruit breadth of 2.76 cm was recorded in T5- Curcuma zedoaria at 2 per cent. Per fruit weight ranged from 1.22 to 1.63 g. The maximum per frit weight of 1.63 g was recorded in T3 (Calotropis gigantea at 1%).The number of fruits per plant ranged from 35.15 to 104.95 and the maximum number of fruits per plant (104.95) was recorded in T6- Calotropis gigantea at 2 per cent. The fresh fruit yield per plant ranged from 54.95 to 121.90 g. Treatment T6 (Calotropis gigantea at 2%) recorded the maximum fresh fruit yield per plant. Factors which influence the yield of the crop like maximum plant height, earliness (minimum days to 50 per cent flowering and fruiting), maximum fruit length, maximum number of fruits per plant were recorded in T6 (Calotropis gigantea at 2%). There was no significant difference for the qualitative characters like Vitamin C (mg 100g-1 ) and oleoresin content (%) with respect to the application of the medicinal plant based formulations. Efficacy of medicinal plant based formulations was studied against various sucking pests during the experimental period. Calotropis gigantea based pesticidal soap formulation showed comparatively good results against thrips population in chilli variety Anugraha under different treatments. Minimum population of whitefly was observed in the treatment T4- Acorus calamus at 2 per cent among various treatments. Acorus calamus based formulation also showed good results with lower pest load against aphids. In general, over all disease incidence in the treatment plot was negligible during the experimental period and Calotropis and Acorus based formulations were showed comparatively good performance in the aspects of growth, yield and pest management in chilli variety Anugraha.ThesisItem Open Access Germination and plant growth responses in Ashwagandha (Withania Somnifera (L.) Dunal) and Kiriyathu (Andrographis paniculata (Burm.F.) Nees) to seed pretreatments(Department of Plantation Crops and Spices, College of Agriculture, Vellayani, 2020) Namitha, Nadesh; KAU; Deepa S, NairGermination and plant growth responses in Ashwagandha (Withania somnifera (L.) Dunal) and Kiriyathu (Andrographis paniculata (Burm.f.) Nees) to seed pretreatments. The present investigation entitled “Germination and plant growth responses in Ashwagandha (Withania somnifera (L.) Dunal) and Kiriyathu (Andrographis paniculata (Burm.f.) Nees) to seed pretreatments” was conducted in the Department of Plantation Crops and Spices, College of Agriculture, Vellayani during 2018-2020 with the objective to standardize pretreatment of seeds for enhanced germination and plant growth in W. somnifera and A. paniculata. The seeds of W. somnifera and A. paniculata used for the study were sourced from Anand Agricultural University, Gujarat, India. The study was carried out in two phases: Phase 1- Pretreatment of seeds for enhanced germination; Phase 2- Evaluation of transplanted seedlings obtained from pretreated seeds for enhanced plant growth. The seeds of W. somnifera and A. paniculata were subjected to various pretreatments viz., physical treatment, hormonal priming, biostimulant priming and biopriming (using microbes). The seeds kept for germination without any pretreatment were taken as the control. In the first phase of the study in W. somnifera, seeds subjected to water soaking recorded higher germination (84.00 per cent), seedling length (13.30 cm) and seedling vigour index (11.16) which were on par with that of hot water treatment. Among the hormonal priming treatments, seeds exposed to GA3 @1500 μM recorded the highest germination (82.00 per cent), seedling length (14.40 cm) and seedling vigour index (11.80) which were found to be on par with GA3 @1500 μM. In biostimulant seed priming, PG @ 10μM primed seeds recorded higher germination (64.00 per cent), seedling length (10.57cm) and seedling vigour index (6.67) and were found to be on par with those of PG @ 1μM primed seeds. The biopriming treatments had no significant effect on germination and seedling length. However, significantly higher seedling vigour index was observed in all the biopriming treatments over the control treatment. Among all the pretreatments tried, water soaking treatment, hot water treatment, GA3 @ 1500μM was recorded significantly higher germination, seedling length and seedling vigour index. In the second phase of the study, the 30 day old seedlings of W. somnifera raised from pretreated seeds and untreated (control) seeds were transplanted and evaluated for plant growth and yield (shoot and root biomass), at harvest (120 DAS). Among the physical treatments, W. somnifera plants derived from water soaked seeds were observed to give higher plant height (60.80cm), number of branches (5.00), collar girth (0.47 cm), shoot biomass (fresh-37.61 g plant-1; dry -7.17 g plant-1) and root biomass (fresh-5.60 g plant-1; dry-0.79 g plant-1). These were observed to be on par in plants from hot water treated seeds, except for the number of branches and shoot biomass. Among the hormonal priming treatments, plants from GA3 @ 1500 μM primed seeds recorded higher plant height (55.57cm), shoot (fresh-27.73 g plant-1; dry-5.09 g plant-1) and root (fresh-5.60 g plant-1; dry-0.79 g plant-1) biomass. The plant height and shoot biomass were found to be on par with that of GA3 @ 1500 μM. In biostimulant priming, plants generated from PG @ 10 μM treated seeds gave the highest plant height (46.37 cm), shoot (fresh-21.40 g plant-1; dry-3.96 g plant-1) and root (fresh-4.36 g plant-1; dry-0.64 g plant-1) biomass. The plant height and shoot biomass were observed to be on par with that of PG @ 1μM. However, the highest number of branches and collar girth were recorded in plants raised from PG @ 1μM and SA @ 1500 μM primed seeds. Among the biopriming treatments, plants derived from the seeds treated with B. pumilis, recorded higher plant height (47.63 cm), number of branches (3.00), shoot (fresh-23.07 g plant-1; dry-4.39 g plant-1) and root (fresh-4.43 g plant-1; 0.63 g plant-1) biomass. The plant height and shoot weight was on par with that of P. fluorescens and the plants from the same treatment recorded the highest collar girth. Among the various pretreatments tried, plants raised from water soaked seeds gave better performance with respect to plant height, number of branches, collar girth and shoot biomass. The plants from hot water treated and GA3 @ 1500μM primed seeds gave the highest root biomass, which was observed to be on par with that in plants from water soaked seeds. In the first phase of the study in A. paniculata, seeds when exposed to physical treatments, higher germination (84.67 per cent), seedling length (15.93 cm) and seedling vigour index (13.38) were recorded in hot water treatment followed by scarification. Among the hormonal priming treatments, GA3 @1500μM primed seeds recorded the highest germination (82.00 per cent), seedling length (16.37 cm) and seedling vigour index (13.42). With respect to biostimulant seed priming, seeds treated with PG @ 1μM recorded higher germination (66.67 per cent) and seedling vigour index (6.03), while seedling length did not show any variation among the biostimulant treatments. Among the biopriming treatments, seeds primed with B. velezensis recorded the highest germination (82.67 per cent), seedling length (11.33 cm) and seedling vigour index (9.29). In A. paniculata, among all the pretreatments tried hot water treated as well as GA3 @ 1500 μM primed seeds recorded higher germination, seedling length and seedling vigour index. In the second phase of the study in A. paniculata, the 30 day old seedlings from pretreated seeds and untreated (control) seeds were transplanted and evaluated for plant growth and yield (whole plant biomass) at harvest (110 DAS). Among the physical treatments, A.paniculata plants derived from hot water treated seeds recorded higher plant height (55.77 cm), number of branches (21.67), collar girth (1.83 cm) and whole plant biomass (fresh-59.60 g plant-1; dry-21.90 g plant-1) at harvest. These were on par with those of scarified seeds. In hormonal priming, the highest plant height (56.80 cm), number of branches (20.00), collar girth (1.90 cm) and whole plant biomass (fresh-56.63 g plant-1 and dry-23.60 g plant-1) were observed in plants raised from seeds primed with GA3 @1500μM. Among the biostimulant priming, higher plant height (48.57 cm), number of branches (16.00), collar girth (1.20 cm) and whole plant biomass (fresh-38.97g plant-1 and dry-13.14g plant-1) were observed in plants raised from PG @1 μM primed seeds. On evaluation of plants derived from bioprimed seeds, those from B. velezensis primed seeds recorded the highest plant height (55.77 cm), number of branches (19.33), collar girth (1.50 cm) and whole plant biomass (fresh-53.97 g plant-1; dry16.87 g plant-1). Among all the seed pretreatments tried, plants generated from hot water treated and GA3@1500μM primed seeds recorded higher plant height, number of branches, collar girth and whole plant biomass. Among the various seed pretreatments tried, W. somnifera seeds exposed to water soaking, hot water and GA3@1500μM and A. paniculata seeds exposed to hot water treatment and GA3@1500μM recorded superior performance with respect to seed germination, seedling vigour, plant growth and yield.ThesisItem Open Access Optimizing propagation techniques in neelayamari (Indigofera tinctoria L.)(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 2019) Mekha Mariam, Abraham; KAU; Krishnakumary, KIndia is acknowledged as one of the world’s richest treasure trove of medicinal plants. Neelayamari (Indigofera tinctoria L.) commonly known as ‘Indian indigo’, is a commercially grown leguminous plant of medicinal importance. The extract of the leaves is reported to have remarkable effect on hair growth and in preventing juvenile greying of hair. Due to the presence of many worthy phytochemicals, the crop is being documented in ‘Ashtangahridaya’ and is being cultivated by several pharmaceutical entrepreneurs, both in public and private sector. Like most of the medicinal plants, the cheapest method of propagation of this crop is through seeds. However, poor germination and vigour of seeds is a major problem in Neelayamari. In addition, heavy loss in seed yield occurs due to the splitting of pods at maturity. The study ‘Optimizing propagation techniques in Neelayamari (Indigofera tinctoria L.)’ was conducted in the Department of Plantation crops and Spices, with the objectives of standardizing the physiological maturity stage in Indigofera tinctoria L. for seed harvest, presowing seed treatments to enhance seed quality and longevity and vegetative propagation technique in Indigofera tinctoria L. through stem cuttings. In order to assess the stage of attainment of physiological maturity for seed harvest in Neelayamari, flowers were tagged on the day of anthesis and the pods were harvested at five days interval from 30 days of anthesis up to the pod splitting stage (63 days after anthesis). It was observed that the values of pod, seed and seedling characters increased up to 45 days after anthesis to reach their highest and thereafter declined till the pod splitting stage (63 days after anthesis). Germination and vigour indices at 45 days after anthesis were 73.80 per cent, 485 and 294 respectively and those at the pod splitting stage were found to be 31.33 per cent, 132 and 65 respectively. Hence, it was inferred that the seeds of Neelayamari reached physiological maturity stage by 45 days after anthesis. The seeds harvested at physiological maturity were dried to 8 per cent moisture content and subjected to various seed treatments before being packed in 700 gauge polyethylene bags. Untreated seeds served as the control. The seeds were stored under ambient conditions upto six months. The scarification treatments included treatment with Conc. H2SO4 for 5, 10 and 15 minutes, mechanical scarification with sand, hot water treatment at 80oC for 20 minutes and 60oC for 30 minutes and hydration for 24 hours. The quality parameters of the stored seeds were recorded at monthly intervals during the storage period and were put for germination test in sterilized sand media. Results pointed out that most of the seed treatments were effective in enhancing germination. High initial germination was recorded in mechanically scarified (95.83 %) and hydrated seeds (93.27%), while the untreated seeds showed a germination of 74.33 per cent. Vigour index I (703 and 698 respectively) and II (430 and 428 respectively) were also the highest in these treatments. Seed treatment with sulphuric acid, however, proved to be detrimental. Seed treatment also helped in extending the viability of the seeds. Mechanically scarified and hydrated seeds retained their germination above 60 per cent for six months during storage (65.67% and 63.67% respectively), while, in untreated seeds, germination reached 61.33 per cent at four months of storage and declined to 44.34 per cent by six months of storage. Seeds treated with sulphuric acid never attained the germination of sixty per cent throughout the storage period and those treated with sulphuric acid for 15 minutes failed to germinate at sixth month of storage. EC was found to be the lowest in hydrated seeds (0.0011 dSm-1) and mechanically scarified seeds (0.0012 dSm-1). The results thus indicated that mechanical scarification of seeds or hydropriming for 24 h can not only improve seed germination and seed quality but also prolong the longevity of the seeds. It was also noticed that all the seed quality parameters declined along the storage period. Attempt to assess the possibility of vegetative propagation in Neelayamari was carried out using hardwood, semi-hardwood and softwood cuttings, exposed to varying doses of IBA (250 ppm, 500 ppm, 750 ppm, 1000 ppm, 1500 ppm, 2000 ppm and 2500 ppm) and charcoal slurry dip. The cuttings were planted in polythene bags and were maintained in a mist chamber. Initially, the experiment was conducted during summer season and only the softwood cuttings treated with 2000 (8.89%) and 1500 ppm IBA (5.53%) survived after 60 days of planting, while all others withered and dried off. The experiment was then repeated during rainy season and the best results were obtained in the season. Softwood cuttings treated with 2000 ppm IBA during rainy season exhibited early sprouting (7.18 days) and a field establishment of 70.67 per cent. In comparison, the semi-hardwood and hardwood cuttings exhibited very low establishment rates of 21.77 per cent and 17.90 per cent respectively. Hence, it was evident that vegetative propagation using softwood cuttings treated with 2000 ppm IBA during rainy season can be relied upon as an alternative propagation method in Neelayamari.ThesisItem Open Access Stock scion interaction in Piper nigrum L. grafts(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 2019) Sarga George; KAU; Sujatha, V SBlack Pepper (Piper nigrum L.) also called ‘King of Spices’ and ‘Black Gold’, is one of the most widely used spices in the world, occupying a position that is supreme and unique. India is one among the countries where black pepper is being widely cultivated. However our productivity is low compared to other pepper producing countries in the world. Among the various factors limiting the productivity of Indian pepper, a soil borne disease called foot rot caused by Phytophthora is of prime importance. Piper nigrum is highly susceptible to Phytophthora foot rot. It has been reported that some South American Piper spp. are immune to Phytophthora. Interspecific crossing between Piper nigrum and immune species has not been successful so far. Grafting on resistant rootstock is a method to escape soil borne inoculum. The present study was conducted to assess the stock and scion interaction in grafts of Piper nigrum L. on different South American species of Piper immune to Phytophthora foot rot and to standardize the best time of grafting. The study was carried out as three experiments, viz., grafting studies, anatomical studies on Piper species and anatomical studies on graft union at different stages of development. Orthotropic as well as plageotropic shoots of P. nigrum, variety Panniyur 1 was grafted on three South American Piper species viz., P. colubrinum, P. auduncum and P. arboreum. Grafting of Piper nigrum on the same species was also done to study the feasibility of such grafting. The trial was laid out in completely randomized design. When orthotropic shoot of P. nigrum was used as scion, highest grafting success was recorded by the grafts of P. nigrum on the same species (100%) followed by the grafts on P. colubrinum (96.66%), P. auduncum (66.66%) and P. arboreum (46.66%). Graft survival after one year of grafting was 90.00, 83.33 and 33.33 per cent for P. nigrum/P. nigrum, P. nigrum/ P. colubrinum and P. nigrum/ P. auduncum grafts respectively. Survival of P. nigrum grafts on P. arboreum was very limited. None of these grafts survived for more than three months after grafting. Irrespective of rootstocks, the best month identified for grafting orthotropic shoot of P. nigrum was March. Although, self grafts showed highest per cent success in grafting, based on the growth of grafted plants (six month old), grafts on P. colubrinum was found to be the best with highest plant height (120.55 cm), number of nodes (18.91) and internodal length (6.32 cm). The graft recovery was less when plageotropic shoot of P. nigrum was used as scion. The highest per cent success was recorded by the grafts of P. nigrum on the same species (93.33%) followed by the grafts on P. colubrinum (66.66%), P. auduncum (36.66%) and P. arboreum (26.66%). March was identified as the best month for grafting plageotropic shoot of P. nigrum on P. nigrum, P. auduncum and P. arboreum. However, grafts on P. colubrinum performed best when grafted during June. Graft survival after one year of grafting was 66.66, 30 and 16.66 per cent for P. nigrum/P. nigrum, P. nigrum/ P. colubrinum and P. nigrum/ P. auduncum grafts respectively. Survival of P. nigrum grafts on P. arboreum was very limited. As far as the growth of grafted plants was concerned, highest growth was shown by the grafts of P. nigrum on the same species. In the anatomical studies of Piper spp. it was observed that, Piper species exhibited a peculiar arrangement of vascular bundles. Two rings of vascular bundles comprising of an outer, cortical and an inner, medullary bundles were observed in all the four Piper species examined. Mucilage canal was present only in P. nigrum while an additional medullary bundle was observed in P. colubrinum. Large pith region was the characteristic feature of P. auduncum and P. arboreum. Examination of graft union at three, six and twelve months after grafting revealed that, graft union formation was completed by six months after grafting. One year old P. nigrum/ P. colubrinum grafts and P. nigrum/ P. auduncum grafts exhibited the formation of a dense necrotic area at the graft interface. Based on the observations, it can be concluded that, due to the peculiar arrangement of vascular bundles in Piper species, matching of all the vascular bundles of stock and scion is difficult. However, complete union of parenchymatous tissues of stock and scion was formed within six months after grafting. But, a proper cambial connection between the grafting partners was not evident. Further studies need to be conducted to find out the reasons for the development of dense necrotic area at the graft interface.ThesisItem Open Access Pollination biology of black pepper (Piper nigrum L.)(Department of Plantation Crops and Spices, College of Agriculture, Vellayani, 2019) Pooja, S; KAU; Sreekala, G SThe present study entitled “Pollination biology of black pepper ( Piper nigrum L.) was carried out at College of Agriculture, Vellayani with specific objectives to study the floral morphology, floral phenology, mode of pollination and breeding system in black pepper. The experiments on floral morphology and floral phenology were carried out in twenty five field grown black pepper plants of variety Panniyur 1. The experiments on the role of wind, insect, rain water and dew on pollination and different types of breeding system were carried out in both field and fifty bush pepper plants of Panniyur 1 maintained in pots. The plants were observed from March 2018 to March 2019 for studying the floral morphology, floral phenology, agents of pollination and breeding system. The floral morphology revealed light green (149 B ) colour in 52 % and dark green colour (140 A) in 48 % of the observed flowers as per the Royal Horticulture Society Colour Charts. The odour of the flower was slightly minty during the first five minutes and then increased to strong minty after 30 minutes and became light minty six hours after keeping in closed containers. Presence of nectar was noticed on the black pepper flowers. Anthesis started from 4-5 pm and was maximum between 6-7 pm and extended upto 12 midnight. The flower size was maximum (1.53 x 1.34 mm) on fifth day of stigma receptivity. The number of flowers in a spike varied from 48 to 98 flowers depending on the length of spike. The number of anthers in each flower was four and anther dehiscence was longitudinal. The anther dehiscence occurred from 11 am and continued till 4 pm and was maximum at 2-3 pm. The number of pollen grains was counted using haemocytometer and it varied from 5,00,000 – 7,00,000 pollen grains per inflorescence. The pollen morphology studied using Scanning Electron Microscope (SEM) revealed monosulcate pollen grains with mean polar diameter of 10.414 µm and mean equatorial diameter of 7.803 µm having an exine thickness of 924.8 nm. The stigma was 4 lobed, wet type and papillate. The duration of stigma receptivity was for 7 days with peak stigma receptivity was on fifth day of anthesis. Pollen was available in an inflorescence from 9 to 12 days from the first day of anthesis depending on length of spike and was available throughout the year in a plant. The longevity of flowers varied from 14 to15 days. Pollen fertility studies by Acetocarmine test revealed that 91% of the pollen were fertile. The pollen viability by 2,3,5-triphenyl tetrazolium chloride (TTC) stain and iodine potassium iodide (IKI) stain was 91.03% and 92.4% respectively. In vitro germination in Brewbakers medium showed highest pollen germination at 5% sucrose. In vivo germination was done through diaminobenzidine (DAB) test and aniline blue fluorescence method for 6 h and 24 h respectively and imaged through fluorescent microscopy. The cross and longitudinal section of the immature spikes revealed the emergence of ovary and stamens. Flower emergence duration ranged from 19 to 20 days. Flowering frequency in black pepper was maximum in the month of July and the flowering intensity was maximum in the fifth day of anthesis. The anthesis period in an inflorescence varied from 9 to 12 days depending on length of spike and was noticed throughout the year in a plant. Duration of spiking was 26.84 days while spiking extended for 259.5 days in a plant population. The fruit is a drupe and the mean period taken from fertilization to maturity was 150-175 days. The percentage of fruit set with rain water in field grown pepper was 92.76% and that for pot grown bush pepper was 92.90%. The percentage of fruit set by experiments on wind pollination resulted in 77.67% with wind alone and 92% with wind and geitonogamy in field grown black pepper plants and 59.39% with simulated wind and 96% with wind and geitonogamy in pot grown bush pepper plants. The floral biology of the black pepper revealed numerous pollen with very small grain size and pendulous spike supporting the characteristics of wind pollinated plant. Presence of dew was observed from June to December and the dew collected from the inflorescence showed the presence of pollen grains which suggests the role of dew also in the pollination of pepper. Three different floral visitors of the black pepper spike were and black ant, yellow crazy and pollu beetle visting day and night. However the role of insects in pollination could not be confirmed, but collection of nectar was noticed by black ant and yellow crazy ant while visiting the flowers. Studies on breeding system revealed high fruit set in geitonogamy followed by autogamy, open pollination and xenogamy. However no fruit set was noticed due to apomixis. The study on pollination biology of black pepper revealed the floral biology, phenology and the role of rain followed by wind and dew in pollination and supported geitonogamy, autogamy, open pollination and xenogamy.ThesisItem Open Access Salicylic acid mediated metabolite elicitation and growth responses in long pepper (Piper longum L.)(Department of plantation crops and spices, college of agriculture, Vellayani, 2019) Krishna Veni Harish; KAU; Deepa S NairA study on “Salicylic acid mediated metabolite elicitation and growth responses in long pepper (Piper longum L.)” was carried out at the Department of Plantation Crops and Spices, College of Agriculture, Vellayani, Thiruvananthapuram, Kerala during 2017-19. The study aimed at assessing the effect of different concentrations of salicylic acid on plant growth, yield and metabolite production in P. longum. The rooted cuttings from the promising variety of long pepper, Viswam plants were exposed to nine foliar spray treatments with varying salicylic acid (SA) concentrations and control treatments viz, SA 0.1 mM (T1), SA 0.5 mM (T2), SA 1.0 mM (T3), SA 1.5 mM (T4), SA 2.0 mM (T5), SA 2.5 mM (T6), ethanol (0.20 per cent) spray (T7), water spray (T8) and control (T9) at 2, 4 and 6 months after planting (MAP). The study was conducted in completely randomized block design (CRD) with three replications. The plant growth parameters, metabolite production, physiological parameters, yield parameters and major nutrient uptake in response to various foliar spray treatments were studied. The plant growth parameters viz., plant height, number of leaves, leaf area, number of primary branches, number of spike bearing branches and shoot weight per plant (fresh and dry weight) were recorded at 3, 5 and 7 MAP. The foliar treatment with SA 0.1 mM (T1) recorded significantly higher values with respect to plant height, number of leaves, leaf area and shoot weight at all stages of observation. All these parameters showed a decreasing trend with increasing concentration of SA. However, no significant variation among the treatments was observed with respect to the number of primary branches and spike bearing branches. The days to emergence of spike and to flowering varied significantly among the treatments tried. SA 0.1 mM (T1) showed earliness with respect to spike emergence (75 days) and flowering (22.67 days). However, the higher concentration took more number of days to emergence of spike (84.67 days) and to flowering (27 days), which was found to be on par with the foliar spray treatments devoid of SA. However, the days from emergence to maturity of spike did not show any significant variation among the treatments. The plant metabolites, viz., total chlorophyll, total proteins and defense enzymes (peroxidase, catalase and superoxide dismutase) at 3, 5 and 7 MAP, recorded significantly higher values in plants subjected to foliar spray with SA 0.5 mM (T2). The mature dark green oven dried spikes were analysed for carbohydrates, piperine, volatile oil and oleoresin content, which varied significantly among the different treatments. The treatment, T2 recorded significantly higher carbohydrate, starch and sugar contents. The same treatment reported the highest values with respect to piperine (1.15 per cent), volatile oil (1.32 per cent) and oleoresin (14.21 per cent) content. This treatment gave approximately 30 per cent increase in piperine content, 12 per cent increase in volatile oil and oleoresin content over the control. However, at higher concentration of SA, T6 (SA 2.5 mM), piperine content (0.90 per cent) was found to be significantly lower and on par with foliar spray treatments devoid of SA. The physiological parameters at 3, 5 and 7 MAP, showed significant variation with regards to the foliar treatments. The foliar spray treatment with SA 0.1 mM (T1) recorded significantly higher values with respect to dry matter production, leaf area index, stomatal conductance and photosynthetic rate at all the stages of observation. The physiological parameters viz., NAR, cell membrane stability index and proline recorded significantly higher values in T2 at all stages of observation. The yield parameters viz., number of spikes, fresh and dry spike yield, fresh and dry root yield and root length varied significantly with different foliar spray treatments. With respect to number of spikes (177.33), fresh (133.88 g) and dry (25.81 g) spike yield, T1 recorded significantly higher values. T1 was found to be on par with T2 with respect to dry spike yield. The root parameters such as fresh (30.15 g) and dry (12.15 g) root yield and root length (70.61 cm) were significantly higher in treatment T2. With regards to dry root yield, T2 was found to be on par with T1. However, harvest index, spike length, spike girth and driage did not showed any significant variation among the treatments. The nutrient uptake by the crop was studied and the results revealed that the plants exposed to T1 showed significantly higher uptake of N (1.27 g plant-1). However, with respect to P (0.059 g plant-1) and K (1.78 g plant-1), treatment T2 recorded higher values. In the study, it was observed that SA 0.1 mM (T1) gave better performance with respect to plant growth parameters and physiological parameters followed by SA 0.5 mM (T2). Foliar spray with SA 0.5 mM gave superior performance with respect to plant metabolites, while high spike and root yield were recorded in foliar spray with SA 0.1 mM and 0.5 mM. Hence, it can be inferred from the study that foliar spray with either concentration of SA 0.1 mM and 0.5 mM. at 2, 4 and 6 MAP could effectively elicit plant growth, yield and metabolite production in Piper longum.ThesisItem Open Access Chitosan mediated metabolite elicitation and growth responses in kasthuri turmeric(curcuma aromatica)(Department of plantation crops and spices, college of agriculture, Vellayani, 2019) Nivya J Thengumpally; KAU; Deepa S NairThe present investigation entitled “Chitosan mediated metabolite elicitation and growth responses in kasthuri turmeric (Curcuma aromatica Salisb.)” was conducted at the Department of Plantation Crops and Spices, College of Agriculture, Vellayani during 2017-2019 with the objective to study the effect of different concentrations of chitosan on plant growth, yield and metabolite production in Curcuma aromatica. The planting material for the study was obtained from Instructional Farm, College of Agriculture, Vellayani. The experiment was laid out in completely randomized block design (CRD) with nine treatments and three replications. The treatments consisted of foliar spray with different concentrations of chitosan and control treatments viz., chitosan 0.5 g l-1 (T1), chitosan 1 g l-1 (T2), chitosan 1.5 g l-1 (T3), chitosan 2 g l-1 (T4), chitosan 2.5 g l-1 (T5), chitosan 3 g l-1 (T6), acetic acid (0.25 per cent) spray (T7), water spray (T8) and control (T9). The treatments were given at 3 and 5 months after planting (MAP). The plant growth parameters viz., plant height, number of tillers, number of leaves, leaf area and shoot weight were recorded at 4 and 6 MAP. All chitosan foliar spray treatments resulted in significantly taller plants compared to treatments devoid of chitosan at 6 MAP, with the highest value (109.91 cm) in T6. T5 and T6 recorded significantly higher number of leaves at 4 MAP while at 6 MAP, it was recorded in treatments, T2 to T6. Similar trend was observed with leaf area also. T4 to T6 recorded significantly higher shoot weight at 4 MAP and T5 to T6 at 6 MAP. The highest dry weight (42.69 g) was recorded in T5 and 63.0 g in T6 at 4 MAP and 6 MAP, respectively. Number of tillers did not show any variation among treatments at both stages of observation. The plant growth parameters viz., rhizome spread, rhizome thickness, number of fingers, root length, root spread and root weight were recorded at 4 MAP, 6 MAP and at harvest. Significant enhancement in rhizome spread was observed only at harvest, in T6, which was on par with T5. The higher concentrations of chitosan foliar spray significantly influenced rhizome thickness at 6 MAP and at harvest; significantly higher values were observed in treatments, T2 to T6 at 6 MAP and T3 to T6 at harvest. At all stages of observation, number of fingers was found to be significantly higher in T5 and T6. Root length and root spread were significantly higher with the treatments T5 and T6 at 6 MAP and at harvest. Significant variation in root weight was observed in C. aromatica only at 6 MAP. The observations on plant metabolites viz., chlorophyll content, total proteins and defence enzymes were recorded at 4 and 6 MAP. T4, T5 and T6 were observed to have significantly higher chlorophyll content among the treatments, at 6 MAP. Total proteins and defense enzymes were observed to give significant variation at both stages of observation. Protein content was found to be significantly higher (6.89 mg g-1) in T5 at 4 MAP and in treatments T4 to T6 at 6 MAP, the highest value being recorded in T6 (8.46 mg g-1). Catalase and peroxidase activity were found significantly higher in T5 and T6 at both stages of observation. SOD activity was found to be significantly higher in T6 at 4 MAP and T4 to T6 at 6 MAP. The observations on curcumin content, volatile oil, oleoresin and carbohydrate content were recorded at harvest. Curcumin, volatile oil and oleoresin was observed to be significantly higher in treatments T4, T5 and T6. T5 and T6 recorded significantly higher carbohydrate content among the various treatments tried. The physiological parameters viz., leaf area index (LAI), stomatal conductance, photosynthetic rate, proline content and cell membrane integrity (CMI) were recorded at 4 and 6 MAP. LAI was found to be significantly higher in treatments T5 and T6 at 4 MAP and T2 to T6 at 6 MAP. With respect to stomatal conductance, T4, T5 and T6 gave significantly higher values at both, 4 and 6 MAP. T6 recorded significantly higher photosynthetic rate among the treatments tried at both stages of observation. All foliar spray treatments with chitosan recorded significantly higher proline content at 4 MAP and T4 to T6 at 6 MAP. CMI was found to be significantly superior in T3 to T6 at 4 MAP, but did not show any variation at 6 MAP. The dry matter production was recorded at 4 MAP, 6 MAP and at harvest. The highest dry matter production was obtained in T6 at all stages of observation and was comparable with T5. The foliar spray treatments did not show any significant variation with respect to net assimilation rate during the period between 4 and 6 MAP. The chitosan foliar spray significantly influenced the rhizome yield, crop duration and harvest index of C. aromatica. T5 (170.95 g plant-1) and T6 (173.27 g plant-1) were found significantly superior to all other treatments with regard to rhizome yield. Crop duration and harvest index of plants exposed to chitosan foliar spray were found to be significantly superior to those devoid of chitosan. Uptake of major plant nutrients (N, P and K) were found to be maximum in T5 and T6. In the present study, chitosan application at different concentrations as foliar spray at 3 and 5 MAP elicited plant growth, production of curcumin, volatile oil, oleoresin and yield. The chitosan concentration of 2.5 and 3 g l-1 gave maximum enhancement in the yield and metabolite production.