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ThesisItem Open Access Economics of dairying in Thrissur district(Department of Rural Banking & Finance Managemnet , College of Cooperation, Banking & Management, Vellanikkara, 2017) Greeni T, Thankachan; KAU; Molly, JosephThesisItem Open Access Plant growth-promotion and root knot nematode management in tomato by Piriformospora indica and rhizobacteria(College of Agriculture, Vellayani, 2016) Shilpa, Varkey; KAU; Anith, K NThe study entitled “Plant growth-promotion and root knot nematode management in tomato by Piriformospora indica and rhizobacteria” was conducted at the Department of Agricultural Microbiology College of Agriculture,Vellayani during the period 2014-2016 with the objective to assess the potential of the root endophytic fungus Piriformosporaindicaand plant growth-promoting rhizobacteria in improving plant growth and suppressing root knot nematode infestation in tomato. The experiment was conducted as in vitro and in vivo studies involving interaction assay between the biological agents and the nematode pest, andin vivo pot culture studies. Egg hatching and J2 mortality asinfluenced by treatment withrhizobacteriaand their cellfree extracts (CFE) were analyzed.Cell free extracts of rhizobacteria significantly reduced egg hatching and increased the mortality ofMeloidogyne incognitajuveniles. After 72 hours, the minimum egg hatching was with CFE of Pseudomonas fluorescensAMB8 (22.33 %) followed by B. amyloliquefaciens (22.66 %) and the maximum was with B. subtilis(27%).Juvenile mortality was highly influenced by the cell free extracts of all the isolates. Higher rate of mortality was observed with undiluted CFE than the diluted ones. Mortality percentage ranged from 68.21% to 99.71% with highest accounted for CFE of B. amyloliquefaciens. Treatment with undiluted CFE of P. indicaresulted in mortality of the J2 by 98% and egg hatching was reduced to 23.33%. Allthe rhizobacterial strains(1x107bacterial cell/ml)negatively influenced the egg hatching(from 30 to 50%) as compared to the control(99 % hatching). Upon 72 hours of incubation, there was only 30 % egg hatching in the case of egg masses treated with Pseudomonas fluorescensAMB8 and in the case of Bacillus amyloliquefaciensit was 30.66 per cent. However, reducing the cell concentration in the test suspension of all the rhizobacterial strains had positive effect on egg hatching. Treatments with cell suspension of all rhizobacterial strainsshowed significantly low mortality of J2 juveniles, with highest mortality forB. amyloliquefaciens (8.56 %) indicating less influence by the rhizobacteria as such. Piriformosporaindicashowed no egg parasitism.Compatibility between Piriformosporaindicaandrhizobacteriawas assessed by dual culture plate assayunder in vitrocondition and it was found that B. pumilus and Pseudomonas fluorescensAMB8 were compatible with the fungus though the test medium differed. The compatible bacteria as single inoculation and combination with P. indicawere used for in vivo analysis. Pot culture experiments using sterile planting medium with single inoculation of the selectedrhizobacteria, Piriformosporaindica, and theircombinationsin the presence or absence of nematode were carried out. All treatments with P. indicashowed root colonization by the fungus.In the presence of nematode, percentage root colonization was found to be increased and the highest was for combination of P. indica and P. fluorescens AMB8. Higher biometric characteristics were observed with nematode untreated plants for all parameters.In the nematode inoculated treatments, application of combination of P. indicaandP. fluorescensAMB8had positive effect on leaf number, fruit number, shoot weight and root weight when compared to the control.Treatment withP.indica resulted in formation of less galls/plant (33.30), egg mass/root system (3.41), eggs/egg mass (306.405), number of nematodes/g of root (54.415) and final nematode population/100cc soil (58) as compared to the control plants, where the values were 142.24, 24.91, 663.54, 220.57, 294.16 respectively. The study established the biocontrol potential of P.indicaagainst root knot nematode in tomato. Application of P. indica in the protray seedling production ensures better performance in terms of plant growth and suppression of root knot nematode infection in the main field.ThesisItem Open Access Development of root endophytic plant growth promoters as bio-inoculants for protray seedlings(College of Agriculture, Vellayani, 2016) Vyshakhi, A S; KAU; Anith, K NThe study entitled “Development of root endophytic plant growth promoters as bio-inoculants for pro-tray seedlings” was conducted at College of Agriculture, Vellayani during the period 2013-15 with the objective to develop microbial root endophytic plant growth-promoters as bio-inoculants in pro-tray seedling production of major solanaceous vegetable crops chilli, tomato and brinjal. Microorganisms were isolated by triturating the roots of vigorously growing seedlings of tomato, brinjal and chilli after surface sanitization. Bacterial isolates were subjected to a preliminary screening on their respective hosts for plant growth promotion. Seedling vigour was assessed under green house condition in portrays using sterile planting medium. Endophytes with plant growth promoting ability selected through the preliminary screening were assessed under in vitro condition using dual culture plate assay for assessing the compatibility with Piriformospora indica (Pi). Piriformospora indica is a wide host root colonizing endophytic fungus which allows the plants to grow under extreme physical and nutrient stress condition. It belongs to the Sebacinales in Basidiomycota. Eight compatible bacterial endophytes (four from tomato, two from chilli and two from brinjal) were further evaluated for their growth promoting ability individually and in combination with P. indica. Bacterial inoculants were provided as seed treatment and the fungal inoculant as additive in the transplant medium. The bacteria were identified as Bacillus megaterium, Alcaligenes faecalis, Streptomyces leeuwenhoekii, Bacillus pumilus, Bacillus megaterium, Bacillus licheniformis, Bacillus thuringiensis thuringiensis based on 16s rRNA sequence homology. and BacillusThe plant growth promoting experiments in tomato indicated that the combination treatment of bacterial strain Streptomyces leeuwenhoekii with Pi was found to be statistically superior in shoot fresh weight, root fresh weight and root dry weight (1764.54 mg, 332.88 mg/plant and 26.45 mg/plant). Treatment Alcaligenes faecalis + Pi was found to be statistically superior in shoot length (15.23 cm) followed by the treatment Streptomyces leeuwenhoekii + Pi (14.45 cm). All the treatment were found to be superior over control. Root colonization by P. indica was not found to be influenced by the combined application with endophytic bacteria. By assessing the plant growth promotion in brinjal, significantly higher values with respect to shoot fresh weight, and root fresh weight ( 844.27 mg/plant, 83.03 mg/plant) were observed with the plant treated with endophytic bacterial isolate. Bacillus thuringiensis + P. indica showed superior mean height of 6.95 cm which was on par with Bacillus thuringiensis (6.74 cm). However the combination treatment of endophytic isolates with P. indica showed superior values compared to control. Analising the efficacy of the endophytic isolates in chilli for plant growth promotion indicated that treatment with the endophytic isolate Bacillus megaterium was found to be have significantly superior values in leaf number, shoot length, shoot fresh weight, and shoot dry weight (5.66, 11.93 cm, 855.20 mg/plant and 87.97 mg/plant). All the treatments including the combinations were found to be superior to control. P. indica has capability to induce resistance against biotic and abiotic stress, including drought, salinity resistance and bacterial, fungal and virus infection in plants. The current experiment suggest that native root endophytic bacteria can be used in combination with P. indica as far as plant growth is concerned. Further studies are required to assess the potential of such combinations in combating drought, salinity etc. plant diseases and helping the plant overcomeThesisItem Open Access Evaluation of cabbage ( Brassica oleracea L. var. capitata ) Genotypes for compactness and internal tipburn resistance under rain shelter(College of Horticulture, Vellanikkara, 2016) Ningappa, Kirasur; KAU; Indira, PThe experiment entitled “Evaluation of cabbage (Brassica oleracea L. var. capitata) genotypes for head compactness and internal tipburn resistance under rain shelter” was carried out in the department of Olericulture, College of Horticulture, Vellanikkara during the period from May to September 2015. The major objectives of the study were to identify compact genotypes with high yield for rain shelter cultivation, to identify genotypes with internal tip burn resistance, a calcium related physiological disorder and also to study the effect of calcium foliar application on the incidence of internal tip burn. Seven cabbage genotypes were evaluated with three different calcium foliar treatments (0%, 0.5% and 1.5%). All the cabbage genotypes showed significant difference with respect to qualitative and quantitative characters studied. Number of wrapping leaves, head length, head breadth, net head weight, head index, harvest index and head compactness directly contributed towards yield. The minimum number of wrapping leaves (8.60) was in genotype G 1 (NS 43) and the genotype G 8 (Saint) recorded the minimum number of non-wrapping leaves (7.70) . The genotype G 1 (NS 43) recorded maximum plant spread (50.70 cm), head length (12.91cm), head breadth (13.40 cm), net head weight (787.33 g) and gross head weight (1136.66 g). The genotype G 4 (F 1 Border 777) recorded the maximum head index (1.31), but harvest index was maximum for the genotype G 8 (69.60 %). All the genotypes formed very compact heads in all Ca foliar treatments, except G 1 (NS 43) which formed loose heads in C 2 (Ca 1.5 %) treatment, medium compact heads in control (C 0 ) and C 1 (0.5 %) treatments. All the genotypes produced conical heads except G 1 (NS 43) which produced round heads. The genotype G 5 (Green Voyager) recorded maximum yield of 6.40 kg per plot. Among the seven genotypes, only the genotype G 1 (NS 43) recorded slight tipburn incidence (4.16 %). Genotypes G 3 (Super Ball 50), G 4 (F 1 Border 777), G 6 (Mahy 118) and G 8 (Saint) were free from pest incidence and genotypes G 2 (Green Challenger), G 5 (Green Voyager) and G 6 (Mahy 118) were free from disease incidence.Effect of different levels of calcium foliar application and the interaction effect were non-significant in most of the characters. However the interaction G 4 C 0 recorded the lowest stalk length (5.25 cm) and interaction G 1 C 2 recorded the highest gross head weight (1365 g). The interaction G 1 C 2 recorded slight incidence of tipburn (1.78 %). There was no pest incidence in the interactions G 8 C 0, G 6 C 1, G 4 C 0 and G 3 C 1. The interactions G 5 C 0, G 2 C 0 and G 6 C 2 registered no disease incidence. Soil samples were collected from all the experimental plots before and after raising the crop. Soil samples were analysed for pH, organic carbon, available P, K, Ca, Mg, Fe and Mn content. There was no significant difference with respect to soil pH, organic carbon, available P, K, Ca, Mg, Fe and Mn content among the plots before and after raising the crop. Index leaf (recently matured wrapping leaf and head) samples were collected from internal tipburn susceptible genotype G 1 (NS 43) and high yielding, resistant genotype G 5 (Green Voyager). Plant samples were analysed for N, P, K, Ca, Mg, Fe and Mn content both in leaf and head. Here also there was no significant difference among genotypes for N, P, K, Ca, Mg, Fe and Mn content both in leaf and head samples. The foliar application of Ca increased leaf calcium concentration in both the genotypes. Maximum leaf Ca content was recorded in the interaction G 5 C 2 (1.20 %) and it was lowest in G 1 C 2 (1.17 %). The genotype G 5 (Green Voyager) produced very compact heads, higher net head weight (1005.83 g), yield per plot (6.40 kg) and high benefit-cost ratio (1.52). It was also resistance to internal tipburn. Hence this genotype can be recommended for off-season cultivation under rain shelter in the central plains of Kerala. From the present study it was found that internal tipburn incidence in cabbage is genotype specific and it can be reduced by Ca foliar application. Only the genotype G 1 (NS 43) was susceptible to internal tipburn among the seven genotypes. Hence more number of genotypes are to be screened in further experiments.