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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 Characterization and evaluation of plant growth promoting rhizobacteria from rice soils of Wayanad(Department of Agricultural Microbiology, College of Agriculture, Vellanikkara, 2021) Wickramasinghe, W R K D W K V; KAU; Girija, DPlant growth promoting rhizobacteria (PGPR) are a group of bacteria that colonize the plant rhizosphere and enhance the growth and yield of plants. The present investigation entitled “Characterization and evaluation of plant growth promoting rhizobacteria from rice soils of Wayanad” was undertaken at the Department of Agricultural Microbiology” during the year 2018-2020, with the objective of isolation, characterization and evaluation of plant growth promoting rhizobacteria from rice soils of Wayanad and formulation of a consortium to improve the growth and yield of rice. Isolation of rhizobacteria with potential plant growth promoting (PGP) activities was attempted from rice rhizosphere soils collected from ten locations in Wayanad district of Kerala. Selective media were used for the isolation of PGPRs including nitrogen fixers, solubilizers of phosphate, K and Zn and fluorescent pseudomonads. A total of 149 isolates obtained on different media were subjected to preliminary screening for growth on selective media, which yielded 32 N-fixers, 16 phosphate solubilizers, four K solubilizers, six Zn solubilizers and two fluorescent pseudomonads. These isolates were evaluated in vitro for PGP activities (production of IAA, NH3, HCN and siderophore) and antagonistic activities against R. solani and X. oryzae. Twenty promising isolates were selected based on their functional efficiency for further characterization using cultural, morphological, biochemical and molecular methods. Four isolates were found to be Gram-positive rods and sixteen isolates were Gram-negative short rods. Eighteen isolates were identified based 16S rRNA gene sequencing and the sequences of all the eighteen isolates deposited in the GenBank of the NCBI. Phylogenetic analysis using MEGA 7 software showed two major clusters and several sub-clusters. A few of the native isolates stood out distinctly from the available accessions in the database, showing that they are genetically diverse. Based on the efficiency of N fixation, P, K and Zn solubilization and other PGP activities, isolates were ranked. Based on ranking, three N-fixers (Bacillus sp. AkNF3, Pseudomonas sp. PkNF4 and Pseudomonas putida KgNF1), three phosphate solubilizers (Bacillus megaterium PkPS1, Acinetobacter schindleri AkPS4 and Achromobacter sp. AvPS1), two K-solubilizers (Microbacterium sp. MvKS1 and Acinetobacter calcoaceticus MvKS3) and two zinc solubilizers (Achromobacter marplatensis ThZnS2 and Cytobacillus kochii PkZnS3) were selected for consortial formulation. Compatibility of ten promising isolates was tested by cross streaking and dual culture methods. Three PGPR based consortia (Consortium 1, 2 and 3) were formulated, each consisting of 5 native isolates (two N-fixers, one each of phosphate, K and Zn solubilizers). These consortia were evaluated in pot culture experiment, along with KAU commercial formulation (PGPR mix-1), at RARS, Ambalavayal, with rice (variety Valichoori) as the test crop. PGPR application was combined with two levels (50% and 75%) of recommended dosage of inorganic fertilizers (RDF). Population of total bacteria, N fixers, P, K and Zn solubilizers was higher in combined application of biofertilizer with inorganic fertilizers than uninoculated treatments and this was indicative of better colonization of native PGPRs in the rice rhizosphere. Growth and yield parameters indicated that application of PGPR consortium with 75% RDF was statistically on par with PoP (KAU) and 100% RDF. Results suggested that 25% inorganic N, P and K can be replaced by using native PGPR consortium without affecting plant growth, yield, plant nutrient content and soil nutrient content. Considering the above parameters, two best consortia (Consortium 2 and Consortium 3) were selected for further field evaluation. Field evaluation was carried out to assess the efficiency of two selected native PGPR consortia at RARS, Ambalavayal. Five treatments included were, consortium 2 + 75% RDF, consortium 3 + 75% RDF, reference biofertilizer PGPR mix-1 + 75% RDF, 100% RDF and farmer’s practice (farm yard manure 5t ha-1 ). Results suggested that root colonization of total bacteria, N fixers, P, K and Zn solubilizers was higher in all treatments of combined application of biofertilizers with 75% inorganic fertilizer than 100% RDF alone. Growth and yield parameters suggested that combined application of Consortium 2 with 75 % RDF was statistically on par with 100% RDF. Therefore, it can be concluded native PGPR strains in consortium 2 (Bacillus sp. strain AkNF3, Pseudomonas putida strain KgNF1, Bacillus megaterium strain PkPS1, Acinetobacter calcoaceticus strain MvKS3 and Cytobacillus kochii PkZnS3) successfully colonized the rice rhizosphere, increased nutrient availability to the plants and produced higher yield. The results also emphasized on the importance of exploiting native, location specific microorganisms as biofertilizer consortium, rather than a common consortium for the entire State. Native PGPR based consortia 2 reduced the 25% of inorganic fertilizer (N, P and K) without affecting the growth and yield of rice. This would be more cost effective and ecofriendly when compared with the use of chemical fertilizers alone. Further multi-locational field trials are required to validate the results before commercialization of this consortium, as a biofertilizer.ThesisItem Open Access Fertigation studies in Papaya (Carica papaya L.)(Department of Fruit Science, College of Agriculture, Vellayani, 2021) Karishma, Sebastian; KAU; Bindu, BThe investigation entitled “Fertigation studies in papaya (Carica papaya L.)” was carried out in Instructional Farm, College of Agriculture, Vellayani during the period 2018 – 2020 with the objectives to standardize the nutrient level for yield improvement through fertigation and foliar nutrition in papaya variety Surya and to study the postharvest management practices for extending the shelf life of papaya fruits. The experiment was undertaken in two parts. In part I, standardization of nutrient level for fertigation and foliar nutrition was carried out in RBD with 14 treatments replicated thrice. A combination of four fertigation doses of 75 %, 100 %, 125 % and 150 % RDF of N (304.89, 406.52, 508.15 and 609.78 g urea plant⁻¹ year⁻¹ respectively based on soil test data in 76 fertigation) and K (426.25, 568.33, 710.42 and 852.50 g MOP plant⁻¹ year⁻¹ respectively based on soil test data in 76 fertigation) and three foliar sprays (1.0 % 19:19:19 at bimonthly interval starting from 4 MAP to 16 MAP, 0.5% ZnSO4 + 0.3% borax at 4 th, 8th, 12th and 16th MAP and water spray at bimonthly interval starting from 4 MAP to 16 MAP) were compared with soil application of recommended dose of NPK (187:170:341 g NPK plant-1 year-1 based on soil test data) (control 1) and 187:170:341 g NPK plant-1 year-1 based on soil test data as organic manures as combination of FYM, poultry manure and vermicompost in the ratio of 2:1:1 (control 2). In control 2, additional requirement of P and K were met through the application of rock phosphate and potassium sulphate respectively. Organic manure (15 kg FYM plant-1 ) was given uniformly to all treatments as basal. Lime and rock phosphate (500g and 850g respectively based on soil test data) was applied uniformly for all treatments as basal except controls. Urea and Muriate of Potash (MOP) were used as fertilizer sources for fertigation and applied weekly from 1 MAP to 20 MAP. Application of different levels of fertigation and different foliar sprays had significant effect on growth, yield and quality of papaya. Growth parameters viz., plant height, stem girth and number of leaves were significantly higher in plants receiving 100 % RD of N and K through fertigation and foliar sprays of 1.0 % 19:19:19 (T4) at bimonthly interval starting from 6 MAP to 16 MAP. T4 also recorded highest leaf area index at 6, 12, 18 MAP and at final harvest, flowering at the shortest height, highest number of female plants and highest fruit set (86.27 %). However, application of 100 % RD of N and K through fertigation and foliar sprays of 0.5 % ZnSO4 and 0.3 % borax at 4 th, 8th, 12th and 16th MAP (T5) initiated earliness in flowering (142.67 days) and harvest (275.00 days). Treatments T4 and T5 were on par in fruit length, fruit girth, fruit volume, pulp percentage, flesh thickness and yield contributing characters like fruit weight, number of fruits per plant and yield per plant (38.30 kg plant⁻1 and 37.60 kg plant⁻1 respectively). Fruit quality parameters viz., TSS, carotenoids, ascorbic acid, total sugar, reducing sugar and non reducing sugar were found highest in T5. Fruits from T5 also registered longest shelf life (5.78 days) and highest mean sensory score for all parameters. Index leaf analysis at 6 MAP revealed highest nitrogen and potassium content of leaf in T10 (150 % RD of N and K through fertigation and foliar sprays of 1.0 % 19:19:19). Calcium, magnesium and sulphur content of leaves were highest in T5, whereas boron and zinc content were highest in T8 (125 % RD of N and K through fertigation and foliar sprays of 0.5 % ZnSO4 and 0.3 % borax). Highest nitrogen and potassium of fruits were observed in T12 (150 % RD of N and K through fertigation with water spray). Highest nitrogen content in soil was noticed in T11 (150 % RD of N and K through fertigation and foliar sprays of 0.5 % ZnSO4 and 0.3 % borax) and T10 witnessed highest potassium content. T4 and T5 were at par regarding B : C ratio (2.58 and 2.54 respectively). In part II of the investigation, postharvest management for extending shelf life of papaya was carried out with nine treatments replicated thrice. Different postharvest treatments given were precooling - hydro cooling (S1), surface sanitization with 150 ppm sodium hypochlorite (S2), external coating with 1% chitosan (S3), precooling followed by external coating with 1% chitosan (S4), packaging with ethylene scrubber 8% KMnO₄ (S5), precooling followed by packaging with ethylene scrubber 8% KMnO₄ (S6), precooling followed by external coating with 1% chitosan and packaging with ethylene scrubber 8% KMnO4 (S₇), hot water treatment followed by waxing with 6% carnauba wax and packaging with ethylene scrubber 8% KMnO₄ (S8) and control (S9). Papaya variety Surya was raised at Instructional Farm, Vellayani and fruits at fully mature green stage were harvested, subjected to different postharvest treatments and packaging was done in CFB boxes and stored under ambient conditions till the end of shelf life. Papaya fruits subjected to precooling followed by external coating with 1% chitosan and packaging with ethylene scrubber KMnO₄ (S7) recorded the longest shelf life of 9.67 days, which was at par with S8 (hot water treatment followed by waxing with 6% carnauba wax and packaging with ethylene scrubber KMnO₄). Physiological loss in weight, ion leakage, percentage disease index, bacterial and fungal count were significantly lowest in S7 and S8 after three days of storage. These treatments also recorded maximum total carotenoids, total soluble solids, total sugar, reducing sugar and minimum acidity after nine days of storage which indicated extended shelf life. Highest mean rank score for sensory attributes were also recorded in treatments S7 and S8 after nine days of storage. In conclusion, application of 100 % recommended dose of N and K (406.52 g urea plant⁻¹ year⁻¹ and 568.33 g plant⁻¹ year⁻¹ respectively) through weekly fertigation from one to 20 months after planting and foliar sprays of 0.5 % ZnSO4 + 0.3 % Borax at 4 th, 8th, 12th and 16th MAP, along with basal application of 850g rock phosphate and 15 kg FYM resulted in increased growth, yield and quality characters of papaya variety Surya with highest B: C ratio. Fruits at fully mature green stage when subjected to precooling followed by external coating with 1% chitosan and packaging with ethylene scrubber 8% KMnO₄ in CFB boxes exhibited a shelf life of 9.67 days in storage under ambient condition in papaya variety Surya.ThesisItem Open Access Gene action and gene expression analysis in tomato (Solanum iycopersicum L.) under moisture stress(Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2021) Chippy, A K; KAU; Beena, ThomasThe present investigation entitled ‘‘Gene action and gene expression analysis in tomato (Solanum lycopersicum L.) under moisture stress” was conducted during the period 2017-2021, in the Department of Plant Breeding and Genetics, College of Agriculture, Vellayani. Thirty-two genotypes including local genotypes of tomato were collected from different sources and studied under three different experiments. In the first experiment, twenty-one F1 hybrids derived from the line x tester mating and their ten parents were transplanted in the field and the treatment mean sum of square due to genotypes was found to be highly significant for all the characters studied which would ultimately indicate diverse nature of selected genotypes. The mean performance showed wide range of variation for most of the characters studied. Among lines, L7 (Pusa Ruby) showed higher mean performance for all-out of nine characters viz., plant height, fruit length, fruit girth, fruit volume, fruit weight, yield per plant, yield per plot, root length, root volume and relative water content. Among three testers, T2 (Kuttichal Local) showed favourable mean performance for seventeen traits viz., plant height, primary branches per plant, number of leaves per plant, number of flowering clusters per plant, number of fruits per cluster, fruit length, fruit girth, fruit volume, fruit weight, yield per plant, yield per plot, vitamin C, total acidity, stomatal frequency, root length, root volume and proline content. Under moisture stress (Second experiment), among the lines, L7 (Pusa Ruby) showed higher mean performance for eleven characters viz., plant height, fruit length, fruit girth, fruit volume, fruit weight, yield per plant, yield per plot, total soluble solids, root length, root volume and pollen viability. Among three testers, T2 (Kuttichal Local) showed favourable mean performance for sixteen traits viz., plant height, primary branches per plant, number of leaves per plant, number of flowering clusters per plant, number of fruits per cluster, number of fruits per plant, fruit length, fruit girth, fruit volume, total soluble solids, total acidity, stomatal frequency, root length, root volume and canopy temperature. Based on general combining ability analysis, the line L6 (Arka Alok) ranked as top by exhibiting significant gca effects for six traits viz., fruit length, fruit girth, fruit volume, fruit weight, specific leaf area and root length. Among the testers, T3 (Kottayam Local) had superior gca effects for Days to 50% flowering, number of flowering clusters per plant, number of fruits per cluster, fruit length, fruit volume, yield per plot, total soluble solids, lycopene, titrable acidity canopy temperature and proline content. Under moisture stress, the line L3 (Akshaya) ranked as top by exhibiting significant gca effects for ten traits viz., primary branches per plant, number of fruits per cluster, number of fruits per plant, fruit weight, yield per plant, yield per plot, stomatal frequency, specific leaf area, canopy temperature and pollen viability. Among the testers, T1 (Palakkad Local) had superior gca effects for plant height, number of fruits per cluster, number of fruits per plant, fruit girth, fruit volume, yield per plant, yield per plot, total soluble solids, relative water content, canopy temperature and proline content. In the case of hybrids, Based on mean performance, the crosses L1 x T1 (Vellayani Vijay x Palakkad Local), L2 x T3 (Anagha x Kottayam Local), L3 x T1 (Akshaya x Palakkad Local), L3 x T3 (Akshaya x Kottayam Local), L4 x T1 (PKM 1 x Palakkad Local), L4 x T2 (PKM 1 x Kuttichal Local), L5 x T1 (Arka Meghali x Palakkad Local), L5 x T2 (Arka Meghali x Kuttichal Local), L5 x T3 (Arka Meghali x Kottayam Local), L6 x T2 (Arka Alok x Kuttichal Local) and L6 x T3 (Arka Alok x Kottayam Local) were superior for different yield characters. Under moisture stress, Hybrids L3 x T1 (Akshaya x Palakkad Local), L3 x T3 (Akshaya x Kottayam Local), L4 x T1 (PKM 1 x Palakkad Local), L4 x T2 (PKM 1 x Kuttichal Local), L5 x T2 (Arka Meghali x Kuttichal Local), L7 x T2 (Pusa Ruby x Kuttichal Local) and L7 x T3 (Pusa Ruby x Kottayam Local) were superior for yield based on mean value. Based on combining ability studies under normal field condition, identified superior crosses such as L1 x T1 (Vellayani Vijay x Palakkad Local), L2 x T1 (Anagha x Palakkad Local), L2 x T3 (Anagha x Kottayam Local), L3 x T1 (Akshaya x Palakkad Local), L3 x T3 (Akshaya x Kottayam Local), L4 x T1 (PKM 1 x Palakkad Local), L4 x T2 (PKM 1 x Kuttichal Local), L6 x T2 (Arka Alok x Kuttichal Local), L6 x T3 (Arka Alok x Kottayam Local), L7 x T1 (Pusa Ruby x Palakkad Local) and L7 x T3 (Pusa Ruby x Kottayam Local) exhibited higher sca effects for yield per plant. Under moisture stress, identified superior crosses such as L1 x T2 (Vellayani Vijay x Kuttichal Local), L2 x T3 (Anagha x Kottayam Local), L3 x T1 (Akshaya x Palakkad Local), L4 x T2 (PKM 1 x Kuttichal Local), L5 x T2 (Arka Meghali x Kuttichal Local), L6 x T2 (Arka Alok x Kuttichal Local) and L7 x T3 (Pusa Ruby x Kottayam Local) exhibited higher sca effects for yield per plant. Based on heterosis, Overall, nineteen hybrids (L1 x T1, L1 x T2, L1 x T3, L2 x T1, L2 x T2, L2 x T3, L3 x T1, L3 x T3, L4 x T1, L4 x T2, L4 x T3, L5 x T1, L5 x T2, L5 x T3, L6 x T1, L6 x T2, L6 x T3, L7 x T1 and L7 x T3) from twenty one crosses revealed significant and positive heterobeltiosis for yield per plant under normal field condition. In the case of gene action, dominance genetic variance (σ2D) is higher than additive genetic variance (σ2A) was observed for all the traits under normal field condition and water stress condition, indicating that traits are controlled by non-additive gene action. Correlation study revealed yield per plant was positively and significantly correlated with the traits viz., primary branches per plant, number of flowering clusters per plant, number of fruits per cluster, number of fruits per plant, fruit girth, fruit volume, fruit weight and yield per plot. Based on qRT-PCR, the expression of both genes (moisture stress related genesSlDREB 1 and SlWRKY 4) was upregulated under water stress in all selected genotypes and the expression was more than moisture stress tolerant check variety. The result is in accordance with the analysis of moisture stress related physiological characters in these genotypes in the field under stress. From the study, identified tolerant sources for moisture stress viz., Akshaya, Pusa Ruby and Kuttichal Local, these lines and tester can be used in breeding programmes for moisture stress tolerance. Based on mean performance and gca, the genotypes Vellayani Vijay, Akshaya, Arka Meghali, Arka Alok and Kottayam local which showed superiority in yield and fruit quality traits can be used for breeding for improvement of yield and quality traits. The hybrids L3xT1 (Akshaya x Palakkad Local), L4 x T2 (PKM 1 x Kuttichal Local), L5 x T2 (Arka Meghali x Kuttichal Local) and L7 x T3 (Pusa Ruby x Kottayam Local) which showed superiority for yield and quality characters with tolerance to moisture stress can be recommended for release after yield trials.ThesisItem Open Access Irrigation scheduling and water stress mitigation strategies in upland rice (Oryza sativa L.)(Department of Agronomy, College of Agriculture, Vellayani, 2021) Gritta, Elizabeth Jolly; KAU; Sajitha Rani, TThe study entitled “Irrigation scheduling and water stress mitigation strategies in upland rice (Oryza sativa L.)” was carried out as two field experiments at the Instructional Farm, College of Agriculture, Vellayani from 2017 to 2020 to identify a suitable variety and irrigation method for upland rice, to standardize irrigation scheduling and to assess the effect of moisture stress mitigation strategies on the growth, yield and economics of upland rice. Experiment I entitled “Identification of suitable variety and standardization of irrigation method” was conducted from January 2019 to May 2019. The experiment was laid out in split plot design with five main plot treatments and two sub plot treatments, in four replications. The treatments included sprinkler irrigation at 100% PE, sprinkler irrigation at 75% PE, drip irrigation at 100% PE, drip irrigation at 75% PE and hose irrigation (farmer’s practice-irrigation given thrice in a week) as main plot treatments and rice varieties Uma and Prathyasa as sub-plot treatments. The height of the plant, number of tillers m -2 , leaf area index and dry matter production were observed to be significantly the highest for the variety Prathyasa irrigated using sprinkler irrigation at 100% PE and hose irrigation was significantly inferior to all other methods of irrigation. The variety Prathyasa irrigated using sprinkler irrigation at 100% PE also recorded the highest number of panicles m -2 (226.00), number of grains per panicle (159.75) and grain yield (4.37 Mg ha -1 ). The highest RLWC and consumptive use (434.25 mm) by the crop was observed in the variety Uma irrigated using sprinkler at 100% PE, followed by drip irrigated plots at 100% PE. The highest crop water use efficiency (1.53 kg m -3 ) was observed in the variety Prathyasa irrigated using hose method and the highest field water use efficiency (0.95 kg m -3 ) was observed in the variety Prathyasa irrigated using sprinkler at 100% PE. 282The economics of cultivation in terms of net returns ( ₹ 1,32,465.50 ha -1 ) and B:C ratio (2.67) were observed to be the highest in the variety Prathyasa irrigated using sprinkler irrigation plots at 100% PE, followed by the variety Prathyasa irrigated using drip irrigation at 100% PE. Field experiment II entitled “Standardization of irrigation scheduling and moisture stress mitigation strategies for upland rice” was conducted during January 2020 to April 2020. The experiment was laid out in split plot design with four main plot treatments and five sub plot treatments in five replications (the best treatment from the experiment I - sprinkler method of irrigation at 100% PE and the variety Prathyasa were used for the experiment II). The main plot treatments included approaches of scheduling irrigation: IW/CPE of 0.8, critical growth stage approach, irrigation to maintain soil moisture at 100% FC and irrigation to maintain soil moisture at 75% FC. The sub-plot treatments included field application of hydrogel polymer (20 kg ha -1 ), seed treatment with hydrogel polymer (10 g kg -1 ), hydrogel polymer (field application @ 2.5 kg ha -1 + seed treatment @10g kg -1 ), foliar application of PPFM (1%) and absolute control. The plant height, number of tillers m -2 , leaf area index and dry matter production were observed to be significantly higher in the plots irrigated at 100% FC, treated with hydrogel polymer (field application @ 2.5 kg ha -1 + seed treatment @10 g kg -1 ), which was followed by the plots irrigated to maintain 2 cm depth of water at critical stages of crop growth. The number of days for 50% flowering, the number of panicles m -2 (233.20), length of panicle (20.36 cm), weight of panicle (3.07 g), number of grains panicle -1 (169.20), grain yield (5.00 Mg ha -1 ) and straw yield (8.07 Mg ha -1 ) were the highest in the plots irrigated at 100% FC and treated with hydrogel polymer (field application @ 2.5 kg ha -1 + seed treatment @10g kg -1 . . The consumptive use by the crop was significantly the highest in the plots irrigated at 100% FC (1265.60 mm) and treated with hydrogel polymer (field application @ 2.5 kg ha -1 + seed treatment @ 10g kg -1 ).The crop water use efficiency recorded the highest value (0.69 kg m -3 ) in the plots irrigated at IW/CPE 283of 0.8 and treated with hydrogel polymer (field application @ 2.5 kg ha -1 + seed treatment @ 10g kg -1 ) and a significantly higher field water use efficiency (0.58) was recorded in the plots irrigated at IW/CPE of 0.8 and treated with hydrogel polymer (field application @ 2.5 kg ha -1 + seed treatment @ 10g kg -1 ) The highest B: C ratio (2.92) and net returns ( ₹ 1,58,000.00 ha -1 ) were obtained from the plots irrigated at 100% FC and treated with hydrogel polymer (field application @ 2.5 kg ha -1 + seed treatment @ 10g kg -1 . The results of the study revealed suitability of the variety Prathyasa, irrigated using sprinkler irrigation at 100% PE for higher yield and monetary returns under upland conditions. It also reflected the suitability of irrigating upland rice at 100 % FC as an effective approach of scheduling irrigation, along with the application of hydrogel polymer (field application @ 2.5kg ha -1 + seed treatment @ 10 g kg -1 ) as the most suitable moisture stress mitigation strategy for upland rice cultivation for enhanced yield and economic returns under water stress conditions.ThesisItem Open Access Productivity enhancement of blackgram (Vigna mungo (L.) Hepper) intercropped in coconut gardens(Department of Agronomy, College of Agriculture,Vellayani, 2021) Pooja, A P; KAU; Ameena, MThe research work entitled ‘Productivity enhancement of blackgram (Vigna mungo (L.) Hepper) intercropped in coconut gardens’ was undertaken at College of Agriculture, Vellayani during 2018-2021. The study aimed to identify shade tolerant blackgram varieties suitable for coconut gardens, to study the effect of foliar nutrition and plant growth regulators on growth and yield of the shade tolerant blackgram varieties intercropped in coconut garden and to work out the economics of cultivation. The investigation was carried out as two experiments: (i) screening of blackgram varieties for shade tolerance, and (ii) performance evaluation of shade tolerant varieties under foliar application of nutrients and growth regulators in rainfed coconut garden. The first experiment was conducted during Rabi 2019-20 in coconut garden having a light intensity equivalent to 50 per cent of that under open condition (56.25 klux), planted at a spacing of 7.6 m x 7.6 m. Seeds of 12 promising blackgram varieties collected from different research stations of south India (Sumanjana, DU 1, DBGV 5, VBN 5, VBN 6, VBN 8, Rashmi, CO 6, TAU 1, TAU 2, Blackgold and AKU 15) and three cultures (Culture 4.5.8, Culture 4.5.18 and Culture 4.6.1), were raised in micro plots laid out in randomized block design with three replications. The crop was raised as per KAU package of practices. The results of the study revealed significant variation in growth characters among the varieties screened for shade tolerance under partial shade in coconut garden. Plants of DBGV 5 were significantly taller (96.89 cm) with higher initial number of leaves at all the stages and was on par with Sumanjana and CO 6. Higher leaf area index (LAI) and leaf area duration were recorded in CO 6 (5.77, 65.66 days) and DBGV 5 (5.36, 58.40 days) followed by Sumanjana. Early flowering was observed in Sumanjana (34.33 days) and DBGV 5 (36.33 days). The variety DBGV 5 had the highest photosynthetic rate and resulted in significantly more pods per plant (23.67) which was on par with CO 6, VBN 5, VBN 6, Sumanjana and Rashmi. DBGV 5 produced the highest seed yield per plant (5.44 g) followed by VBN 5 and Sumanjana. Haulm yield per plant was higher for DBGV 5 (19 g) and was on par with VBN 5, Sumanjana and CO 6. The variety DBGV 5 produced the highest seed yield (1183 kg ha-1 ) followed by VBN 5, Sumanjana and CO 6. A higher harvest index of 0.24 was recorded by Sumanjana which was on par with DBGV 5 and VBN 6. Among the varieties screened, five varieties which performed better in terms of yield per unit area under the partial shade in coconut garden viz., DBGV 5, VBN 5, Sumanjana, CO 6 and VBN 6 were selected for experiment II undertaken in summer 2020 followed by the confirmatory trial during Rabi 2020 -21. The experiment was laid out in split plot design with five varieties (v1 - Sumanjana, v2 - DBGV 5,v3 - VBN 5,v4 - VBN 6,v5 - CO 6) as main plot treatments and six foliar sprays of nutrients and plant growth regulators as subplot treatments (f1: 19:19:19 (1%) at 45 and 60 DAS, f2: SOP (0.5%) at 45 and 60 DAS, f3: NAA 40 mg L-1 and salicylic acid 100 mg L-1 at pre-flowering (30-45 DAS) and 15 days later, f4: f3 + f1, f5: f3 + f2 and f6: Control - KAU POP). Among the varieties, Sumanjana (v1) grew taller during both the seasons and was comparable with CO 6 and DBGV 5 at harvest. Sumanjana produced higher number of branches with more number of leaves during both the seasons. At flowering, higher LAI, number and dry weight of nodules per plant were realized by Sumanjana and was on par with CO 6 (v5) in summer and DBGV 5 (v2) in Rabi. Sumanjana exhibited the highest crop growth rate (CGR) and relative growth rate (RGR) during both the seasons at 45-60 DAS. However, DBGV 5 recorded the highest net assimilation rate (NAR) between 30-45 DAS and 45-60 DAS during both the seasons. The highest chlorophyll content was recorded by DBGV 5 (1.96 mg g-1 fresh tissue) during summer and by Sumanjana (2.36 mg g-1 fresh tissue) during Rabi. The highest stomatal conductance (30.22 m moles m-2 s -1 and 28.34 m moles m-2 s -1 ) and lower stomatal index (15.16% and 13.34%) were recorded in Sumanjana during both the seasons. The variety Sumanjana flowered earlier compared to other varieties during both the seasons and produced the highest number of pods per plant (27.30 and 26.54). Hundred seed weight was significantly higher for DBGV 5 (5.01 g and 4.92 g) and remained at par with Sumanjana (4.99 g and 4.88 g) during both the seasons. Seed yield, haulm yield and total dry matter production (TDMP) were higher for Sumanjana and comparable with DBGV 5 during both the seasons. Sumanjana recorded higher NPK uptake during both the seasons followed by DBGV 5. The subplot factor foliar spray had significant effect on growth, physiological and yield attributes of blackgram varieties. Foliar spray of 19:19:19 (1%) at 45 and 60 DAS + foliar spray of NAA 40 mg L-1 and SA 100 mg L-1 at pre-flowering and 15 days later (f4) resulted in significantly taller plants, more number of branches and leaves. The highest CGR, RGR (at 45-60 DAS), LAI, number and dry weight of nodules per plant at flowering were recorded in f4 during both the seasons. During summer, f3, f4 and f5 recorded higher NAR between 45-60 DAS. Higher chlorophyll content and stomatal conductance were recorded by f4 during both the seasons. Plants supplied with f3 attained 50 per cent flowering earlier and was on par with f5 during both the seasons. Highest number of pods per plant, 100 seed weight, seed yield, haulm yield and TDMP were recorded by f4 during both seasons. The grain protein content was improved by f4 and was on par with f3, f1 and f5. The NPK uptake was higher in f4 and was on par with f3 and f5 during summer. Significantly higher organic carbon, available N and P was recorded in f4. Among the treatment combinations, Sumanjana (v1) with f4 produced taller plants at two months after sowing (MAS), higher number of branches and leaves per plant during summer and Rabi. Leaf area index, number of nodules and dry weight of nodules at flowering were higher for v1f4 followed by v2f4. Sumanjana in combination with f4 measured significantly higher CGR and RGR (at active growth stages), highest chlorophyll content, stomatal conductance and lower stomatal index during both the seasons. The variety Sumanjana with f4 produced superior number of pods per plant (30.24 and 29.40) and hundred seed weight during summer and Rabi. A higher seed yield was realized in v1f4 (1750 kg ha-1 ) which was on par with v2f4 (1713 kg ha-1 ) during summer. Seed yield was the highest (1700 kg ha-1 ) in v1f4 during Rabi. Haulm yield and TDMP recorded were higher for v1f4 and was on par with v2f4 during both the seasons. The available N status in soil was higher during both the seasons in v1f4 with the highest NPK uptake during Rabi. Sumanjana and DBGV 5 with f4 realized higher mean net income (₹ 70411 ha-1 and ₹ 61256 ha-1 ) and mean B: C ratio (2.04 and 1.95). The present study identified DBGV 5 and Sumanjana as shade tolerant blackgram varieties with superior growth and yield attributes under partial shade and could be recommended for intercropping in coconut garden. Further, the yield of the shade tolerant varieties could be enhanced by recommended dose of nutrients as per KAU package supplemented with foliar spray of 19:19:19 (1%) at 45 and 60 DAS + foliar spray of NAA 40 mg L-1 and SA 100 mg L-1 at preflowering (35 DAS) and 15 days later. Sumanjana and DBGV 5 raised under partial shade in coconut garden with recommended dose of nutrients supplemented with the above said foliar spray realized higher mean net income and mean B: C ratio.ThesisItem Open Access Input optimization for short duration Red gram [Cajanus cajan (L.) Millsp.](Department of Agronomy, College of Agriculture,Vellayani, 2021) Anjana Devaraj, G; KAU; Sheeba, Rebecca IsaacThe study entitled “Input optimization for short duration red gram [Cajanus cajan (L.) Millsp.]” was conducted at College of Agriculture, Vellayani during 2017 - 2020 with the objectives, to assess the suitability of two short duration varieties of red gram, standardize the spacing and nutrient management practices for short duration red gram and to examine the legume effect on succeeding fodder maize crop. The investigation was done as three experiments (i) assessment of the suitability of two short duration varieties and standardization of spacing and nutrient levels (ii) assessment of legume effect on fodder maize and (iii) nutrient scheduling in red gram. The experiment I was laid out in randomized block design (RBD) with three replications during Rabi season (November to March) in 2018 - 2019 and the confirmatory experiment, during 2019 - 2020. The treatments included combinations of varieties [v1: APK 1; v2: Vamban (Rg) 3], spacings [s1: 40 cm x 20 cm; s2: 60 cm x 30 cm] and nutrient levels [ n1: 40:80:40, n2: 30:60:30; n3: 20:40:20 kg NPK ha-1 ]. Half nitrogen (N), potassium (K) and full phosphorus (P) were given basally, remaining as top dressing, 30 days after sowing (DAS). Farmyard manure (FYM) was applied uniformly @ 12. 5 t ha-1 . The varieties, spacings and nutrient levels had significant influence on the growth characters of red gram at the different stages of observation. Variety Vamban (Rg) 3 (v2) recorded significantly taller plants, higher number of branches and root parameters compared to APK1 (v1) during both the years of experimentation. The wider spacing, s2 (60 cm x 30 cm), the highest nutrient level, n1 (40:80:40 kg NPK ha-1 ) and the combination, v2s2n1 resulted in superior values for plant height, number of branches per plant, root volume and root dry weight, while narrow spacing (40 cm x 20 cm) recorded the highest number and weight of nodules per plant. The interactions also exerted significant influence on growth parameters with the interactions involving v2, s2 and n1 recording higher values. The variety APK 1 showed earliness in flowering with significantly higher average pod weight, 100 seed weight, seed yield (1.04 t ha-1 ) and haulm yield (3.70 t ha-1 ). Narrow spacing and the highest nutrient level recorded superior values for average pod weight, seed and haulm yields. The interactions also resulted in significant variations in yield attributes and yield. Pooled analysis of yield data of the two years registered the highest seed yield (1.38 t ha-1 ) in v1s1n1 (APK 1 + 40 cm x 20 cm + 40:80:40 kg NPK ha-1 ). Maximum dry matter production (DMP), crop growth rate (CGR) and seed protein content were recorded in APK 1 and at the highest nutrient level. Among the spacings tried, wider spacing resulted in the highest DMP and seed protein, while CGR was higher in the narrow spacing. The partial factor productivity (PFP) for N, P and K were superior in the combination v1s1n1 in both years. Individual effects of the variety APK 1, narrow spacing and the highest nutrient level recorded maximum nutrient uptake and in the combinations of APK 1 or Vamban (Rg) 3 with 40 cm x 20 cm and 40:80:40 kg NPK ha-1 . Available soil N and microbial counts assessed after the experiment were the highest after APK 1. Wider spacing and the highest NPK level recorded maximum soil available nutrient status, while microbial counts, at narrow spacing. Soil nutrient balance sheet computed for N was positive during both years. The balance sheet for P was positive for all the treatment combinations involving wider spacing during the first year. During the second year, all treatments showed positive balance for P except v1s1n1, v1s1n2, v1s2n2 and v2s2n3. Nutrient balance for K was positive in treatments v1s1n1, v1s2n1 and v2s1n1 during the both years. Pooled mean of the economics of cultivation during the two years revealed maximum net returns per hectare (₹ 88621/-) and B:C ratio (2.03) in v1s1n1 (APK 1 + 40 cm x 20 cm + 40:80:40 kg NPK ha-1 ). The legume effect of red gram on fodder maize was assessed during Kharif season, June to August 2019. Crop residues (root + shoot + fallen leaves) of red gram were incorporated in situ and allowed to decompose for two months. The maximum quantity of residues (4.83 tha-1 ) was generated in the treatment combination T7, Vamban (Rg) 3 + 40 cm x 20 cm + 40:80:40 kg NPK ha-1 imposed in red gram, which was on par with T1, the combination, APK 1 + 40 cm x 20 cm + 40:80:40 kg NPK ha-1 (4.75 tha-1 ). There were no marked variations in the biochemical characters of residues, while C: N ratio was significantly narrower in T1 (18.2: 1) and T7 (18.9:1). Residue incorporation improved the soil chemical properties and at 60 days after residue incorporation (DAI), maximum soil pH and C pool (total organic carbon and labile carbon) were estimated in treatment T7, and recalcitrant organic carbon, in T1. Soil available N, P status and dehydrogenase activity were higher in T1, and available K, in T7 at 60DAI. Fodder maize seeds (variety, African tall) were sown during the third week of June in the residue incorporated plots. Green and dry fodder yields (33.61 and 11.37 t ha-1 respectively) were the highest in the treatment T7 which was on par with T1 (32.85 and 11.08 t ha-1 respectively). Soil available NPK status were found to decline from the initial status with fodder maize cultivation. The nutrient scheduling experiment was conducted during Rabi season, 2019 - 2020, in RBD with nine treatments and three replications. The variety APK 1, spacing 40 cm x 20 cm and nutrient level 40:80:40 kg NPK ha-1 found superior in Experiment I were adopted. The integrated nutrient management (INM) practices evaluated were T1: 100 % NPK as chemical fertilizers, T2: 100 % N + 50 % P + 100 % K + P solubiliser, T3: 100 % N + 100 % P + 50 % K + K solubiliser, T4: 100 % N + 50 % P + 50 % K + P solubiliser + K solubiliser, T5: T1 (50 % N foliar), T6: T2 (50 % N foliar), T7 : T3 (50 % N foliar), T8 : T4 (50 % N foliar) and T9 : Absolute control: No fertilizers. The entire dose of N was given as soil application in T1 to T4 and foliar spray of 50 per cent N in T5 to T8 with urea (2 %) at 30 and 45 DAS. Phosphorus and K solubilisers (Bacillus megaterium and Bacillus sporothermodurans respectively) were mixed with powdered FYM in the ratio 1: 50 separately, and 10 g of each mixture was added in soil one week after basal fertilizer application. The INM practice of 100 per cent N + 50 per cent P + 50 per cent K along with P and K solubilisers (T4) recorded significantly taller plants (109.70 cm), maximum number of branches (6.5) at harvest, whereas weight of nodules per plant at flowering (0.59 g) and root parameters were significantly the highest in treatment T8. Average pod weight (0.62 g) and seed yield (1.48 t ha-1 ) were superior in T4 and on par with the combination involving foliar nutrition, T8 (1.46 t ha-1 ). Integration of P and K solubilisers with chemical fertilizers (100 % N and 50 % P and K), registered 50 per cent higher yield than the absolute control. Among the agronomic indices, DMP at 100 DAS (34.18 g plant-1 ), CGR at 80 - 100 DAS (3.44 g m-2 day-1 ) were the highest in T4, and RGR, in T2 followed by T4. Substitution of 50 per cent Pand K with biofertilizers recorded maximum uptake of N, P and K and physiological efficiencies for the nutrients. Computation of nutrient balances with the INM practices adopted revealed the highest positive balance for N in T8, P in T4 and for K in T7. Economic analysis showed the treatment T to record the highest net return per hectare (₹ 94722 /-) and B: C ratio (2.05). Based on the results it could be concluded that the short duration red gram varieties, APK 1 and Vamban (Rg) 3 are suitable for cultivation in the southern laterites of Kerala. The variety APK 1 was superior in terms of yield and profit and can be recommended for planting at a spacing of 40 cm x 20 cm and an NPK dose of 40:80:40 kg ha-1 based on the soil test results. Evaluation of the legume effect of red gram revealed significant increases in soil fertility status with residue incorporation. Among the treatments imposed in red gram, irrespective of the variety, the residual effect realized with red gram planted at 40 cm x 20 cm spacing and fertilized with 40:80:40 kg NPK ha-1 was found to be superior in terms of fodder yield in the succeeding crop of maize. The integrated nutrient management practice that proved profitable in APK 1 involved application of 40:40:20 kg NPK ha-1 as chemical fertilizers along with P and K solubilisers, the entire dose in soil.ThesisItem Open Access Bio-efficacy of tank mixed herbicides and urea in wet seeded rice(Department of Agronomy, College of Agriculture, Vellanikkara, 2021) Thumu, Venkateswara Reddy; KAU; Meera, V MenonThe use of herbicides has become an indispensable part of agriculture, particularly in rice cultivation, where weeds are the most harmful of the biotic constraints to production. A usual practice among rice farmers in the Kole lands of Kerala is the tank mixing of herbicides, for a broader spectrum of weed control, enhanced weed control efficiency and reduction in the cost of application. However, mixing of herbicides is done without any knowledge of the probable synergistic or antagonistic interactions on weed flora. Herbicides are also mixed with fertilizers like urea under the common belief that herbicidal efficiency is enhanced by this practice. Application of herbicides may affect various plant pathogens and microbial bioagents which occur naturally in the rice ecosystem. Information of the effect on main disease causing as well as beneficial microorganisms would help in selecting appropriate herbicides. Hence the major objectives of the research programme entitled “Bio-efficacy of tank mixed herbicides and urea in wet seeded rice” were to study the synergistic or antagonistic effect of tank mixing of commonly used herbicides, and to evaluate the efficiency of these herbicides on mixing with urea, on major weeds of rice. The effect of these herbicides on beneficial and pathogenic microorganisms were also investigated. Two field experiments were conducted at Alappad padasekharam in the Kole lands of Thrissur from October to January 2019-20 and 2020-21. The soil of experimental field was clayey in texture, high in organic carbon (1.1-1.3%), low available nitrogen (180-188 kg/ha), and medium phosphorus (20-21.5 kg/ha) and potash (152-159 kg/ha), with a soil pH of 4.5-4.7. The feasibility of mixing herbicides was evaluated in experiment I (Bio-efficacy of tank mixed herbicide combinations in wet seeded rice). There were fourteen treatments and they included tank mixtures and sequential applications of five herbicides viz., fenoxaprop-p-ethyl (0.06 kg/ha), (chlorimuron-ethyl + metsulfuron-ethyl) (0.004 kg/ha), carfentrazone ethyl (0.02 ii kg/ha), bispyribac-sodium (0.025 kg/ha), and (cyhalofop-butyl + penoxsulam) (0.15 kg/ha). These were compared with two broad spectrum herbicides, bispyribac-sodium (0.025 kg/ha) and (cyhalofop-butyl + penoxsulam) (0.15 kg/ha), as well hand weeded and unweeded controls. In experiment II (Bio-efficacy of tank mixed herbicides and urea in wet seeded rice), there were twelve treatments. Six herbicides, viz., cyhalofop butyl (0.08 kg/ha), (cyhalofop butyl + penoxsulam) (0.15 kg/ha), bispyribac-sodium (0.025 kg/ha), fenoxaprop-p-ethyl (0.06 kg/ha), carfentrazone ethyl (0.02 kg/ha) and (chlorimuron ethyl + metsulfuron methyl) (0.004 kg/ha) were applied with and without urea (1%) mixing. Hand weeded and unweeded controls were also included for comparison. Randomized Block Design with three replications was adopted for both experiments. Wet seeding of rice at the seed rate of 100 kg/ha was done. Nitrogen, phosphorus and potassium @ 90:35:45 kg/ha were supplied through urea, factomphos and muriate of potash (KAU, 2016). In experiment III (In vitro evaluation of herbicides on beneficial and pathogenic microorganisms) treatments included the effect of herbicides mentioned in experiment II which were evaluated under in vitro conditions with recommended, higher and lower doses on beneficial microbial bioagents (Trichoderma viride and Pseudomonas fluorescens) and pathogenic microorganisms (Rhizoctonia solani, Pyricularia oryzae and Xanthomonas oryzae pv. oryzae). Factorial Completely Randomized Block Design was adopted with 18 treatments and three replications each. Tank mixing of herbicides was found to be more effective than their sequential application for most of the combinations. Tank mixed combination of (cyhalofopbutyl + penoxsulam) with (chlorimuron-ethyl + metsulfuron-methyl) showed synergistic effect and had lowest weed density (32, 16 and 20 nos./m2 ), lowest weed dry matter production (14.68, 50.50 and 88.95 kg/ha), and highest weed control efficiency (91, 88, and 82%) at 15, 30 and 60 days after application respectively. The number of tillers per sq. m (411), number of panicles per sq. m (288), number of grains per panicle (103), percentage of filled grain (91.6) at harvest, nutrient uptake by rice at 60 DAS (105.06, 14.32 and 74.28 kg/ha of N, P and K respectively), grain iii yield (3.97 t/ha), net returns (Rs.71,406/ha) and benefit: cost ratio (2.25) were highest in the same treatment. The next best treatment was fenoxaprop-p-ethyl + bispyribac sodium. On tank mixing of herbicides with urea, bispyribac-sodium and urea interacted synergistically, resulting in highest weed control efficiency (82.5 and 78% at 15 and 30 days after application respectively), highest grain yield (5.03 t/ha), and profitability (Rs. 93,509/ha) over the other treatments. Mixing of (cyhalofop-butyl + penoxsulam) with urea could also be recommended for good results (grain yield of 4.94 t/ha and net returns of Rs.87,463/ha). In vitro evaluation of herbicides revealed that bispyribac-sodium and (cyhalofop-butyl + penoxsulam) had greatest inhibitory effect on pathogenic microorganisms Rhizoctonia solani and Pyricularia oryzae, but showed no effect on Xanthomonas oryzae pv. oryzae, and were less harmful to biocontrol agents Trichoderma viride and Pseudomonas fluorescens at recommended doses. Tank mix combination of (cyhalofop-butyl + penoxsulam) with (chlorimuronethyl + metsulfuron-methyl) was the best treatment with compatibility, efficient weed control, high grain yield and net returns. Tank mixing of bispyribac-sodium with urea 1% had synergistic effect resulting in highest weed control efficiency, production and profitability over the other treatments. Mixing of (cyhalofop-butyl + penoxsulam) with urea 1% could also be recommended for good results. Bispyribac-sodium and (cyhalofop-butyl + penoxsulam) were the best herbicides on in vitro evaluation in their effect on pathogenic microorganisms Rhizoctonia solani and Pyricularia oryzae, and at recommended doses were compatible with biocontrol agents Trichoderma viride and Pseudomonas flourescens.ThesisItem Open Access Tribal labour migration of Wayanad district: an impact analysis(Department of Agricultural Extension, College of Agriculture, Vellayani, 2021) Mano Sandesh, V V; KAU; Anilkumar, AThe study entitled “tribal labour migration of Wayanad district: an impact analysis” was undertaken during 2016-2020at College of Agriculture, Vellayani, with the major objectives of studying the impact of tribal labour migration on the livelihood of tribespeople and the agricultural situation of Wayanad district. Factors influencing the tribal labour migration and their migration proneness were also studied. The study was conducted in all the four blocks of Wayanad district viz., Mananthavady, Sulthan Bathery, Kalpetta and Panamaram. From each block 30 tribal migrants, 10 tribal non migrants and 10 non tribal significant other respondents were selected randomly making a total of 200 respondents. The data collected were statistically analysed using arithmetic mean, percentage, correlation analysis and non parametric test. The study revealed that half of the respondents had medium level of livelihood capital index before migration. Most of the tribal migrants possessed medium level of human capital, social capital, natural capital and financial capital before migration. A lion share (61.66%) of the respondents had low level of physical capital before migration. The analysis of livelihood after migration revealed that more than half (60.83%) of the tribal migrants had high livelihood capital index after migration. Immense increase (30.6%) in physical capital of tribespeople due to migration was obvious from study results and it was remarkable for tribes belonging to Kattunaikan and Paniya communities. This caused a temptation for migration among tribal non migrants. A substantial number (85.83%) of tribal migrants had medium social capital and 73.33 per cent had medium of human capital after migration. There was a decrease in the social capital of tribespeople due to migration and this was an indication that tribal migrants were not actively involving in the social activities. After migration 83.33 per cent of tribal migrants had only low natural capital. This tremendous decrease in natural capital indicate poor use of natural resources by tribespeople. Majority (70.83%) of the tribal migrants had a high financial capital after migration. The increase in the financial capital and physical capital was highly significant in uplifting the livelihood capital index of tribal migrants. Sixty five per cent of the tribal non migrants had high livelihood capital index. Globalisation has also affected the life style, food habits and education of tribespeople. Cultural changes were observed among the young tribespeople and many of them have turned to non agricultural labour activities. This also helped them to achieve higher financial capital and there by increased livelihood capital index. Analysis of the relationship between the dependent variable livelihood capital index and profile characteristics of tribespeople revealed that, viz. age, annual income, education, land holding, experience in agriculture, level of aspiration and economic motivation correlated significantly. Marital status and wage per day correlated significantly to livelihood capital index before migration while they were not significant after migration. Most of the tribal migrants had medium migration proneness. Young tribespeople were found to be more prone to migration than middle or old aged tribespeople. Majority of the tribal non migrants had lower migration proneness and they assumed that for a sustainable livelihood, migration is not a necessary factor. On correlation analysis it was found that education, wage per day, political orientation, type of house, level of aspiration and risk preference positively and significantly correlated with migration proneness whereas age, marital status, debt and experience in agriculture correlated negatively with migration proneness. Regarding the nature of migration of tribal migrants, majority of the migrants were daily and seasonal migrants and none of them migrated permanently. A higher percentage of tribal migration was interstate. They migrated mostly to Coorg area via Kutta region of Thirunelli Panchayath and Karnataka via Mysore road to work as agricultural labourers mainly for ginger cultivation. The entire tribal migrants moved in groups and the decision to migrate was induced rather than self chosen. Majority of tribal migrants went for agriculture labour work and were non registered migrants. Unemployment or loss of employment was the main push factor for migration. Low wages, poverty, malnutrition, small holding, landlessness, decline of natural resources, frustration, alienation from community and indebtedness were other major push factors of migration. Superior opportunity for employment was the main pull factor for migration. Better job security, superior opportunity to earn higher income, opportunity to obtain desired specialization, education, skill or training and better food were other major pull factors of migration. Scarcity of agricultural labourers was the major consequence of tribal labour migration, which in turn caused a decrease in agricultural land area. Change in the cropping pattern of Wayanad district, use of agricultural land for non agricultural purposes and immigration of agricultural labourers from other states to Wayanad were found to be other consequences of tribal labour migration. Shortage of skilled labourers, significant change in wage structure and decline of indigenous knowledge were also the results of tribal labour migration. In the light of the study some of the important policy prescriptions for the consideration of the government are (i) create better local job opportunities in the agriculture sector (ii) strengthen police patrolling in the tribal colonies to control illegal marketing of alcohol (iii) implement stringent registration procedures for tribal who are migrating (iv) evaluate the livelihood of tribal migrants periodically (v) formulate new programs and activities to conserve the traditional life style of tribespeople (vi) open and maintain rehabilitation centers in tribal areas to reduce alcohol addiction among tribal migrants (vii) initiate counseling and guidance centers for tribal migrants (viii) conduct regular inspections at migratory places to discourage exploitation of tribespeople (ix) ensure decent and indiscriminating wage structure for tribespeople in their native places.
