CALIBRATION AND CATEGORIZATION OF PLANT AVAILABLE SOIL SILICON IN DIFFERENT RICE ECOSYSTEMS FOR EVALUATING DROUGHT AND DISEASE RESISTANCE IN RICE GENOTYPES
| dc.contributor.advisor | PRAKASH, N B | |
| dc.contributor.author | NARAYANASWAMY, C | |
| dc.date.accessioned | 2017-02-22T08:22:11Z | |
| dc.date.available | 2017-02-22T08:22:11Z | |
| dc.date.issued | 2007-02 | |
| dc.description.abstract | The plant available soil Si content of Mangalore, Ponnampet and Mudigere as extracted by ammonium acetate and acetic acid ranged from 7.1 to 64.6 and 15.9 to 78.4 ppm, respectively. The soils of Ponnampet recorded lowest available Si followed by Mangalore and highest available Si was recorded in Mudigere soils. In general, 0.5M acetic acid extractable available Si was higher than the ammonium acetate extractable. It was observed that nearly 75 to 85 per cent of the studied soils were categorized as low (< 20 ppm) to medium (20 - 40 ppm) in available Silicon content. The plant available soil Si extracted by various extractants irrespective of the soils used for the study was in the order of 0.005M H2SO4 > 0.1M citric acid > N NaOAc-2 > N NaOAc-1 > 0.5M acetic acid-3 > 0.5M acetic acid-2 > 0.5M acetic acid-1> 0.01M CaCl2 > 0.5M NH4OAc > distilled water-4 > distilled water-1. Among the methods studied, plant available Si extraction with N NaOAc-1 appeared to be the most suitable for evaluating Si availability followed by extraction with 0.5 M acetic acid-2 and N NaOAc-2. These extractants showed the highest degree of significant correlation with the per cent Si and its uptake in straw and grain. The critical levels for plant available Si in the soil as extracted by different extractants ranged from 14 ppm (distilled water-1) to 207 ppm (0.005 M H2SO4). There was wide variation in low, medium and high categories of plant available Si for different extractants calculated based on per cent relative yield. The critical level of Si in straw and grain were 2.9 and 1.2 ppm, respectively. There was a greater variation in Si accumulation among different rice genotypes studied. Rasi recorded maximum Si uptake followed by BI-33. The Si accumulation was highest at harvesting stage followed by flowering stage and least at maximum tillering stage. The silicon accumulation was maximum in submerged conditions than aerobic conditions. The grain and straw yields increased significantly with the application of silicon at 117 kg Si ha-1 as calcium silicate along with varied N levels at both the locations over non silicon treated plots. Interaction between Si and N was positive and found to be statistically significant in obtaining higher grain and straw yields, reduced per cent blank spikelets and insects and diseases. | en_US |
| dc.identifier.other | TH-8949 | |
| dc.identifier.uri | http://krishikosh.egranth.ac.in/handle/1/5810002141 | |
| dc.language.iso | en | en_US |
| dc.publisher | UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU | en_US |
| dc.sub | Soil Science and Agriculture Chemistry | en_US |
| dc.subject | null | en_US |
| dc.theme | CALIBRATION AND CATEGORIZATION OF PLANT AVAILABLE SOIL SILICON IN DIFFERENT RICE | en_US |
| dc.these.type | Ph.D | en_US |
| dc.title | CALIBRATION AND CATEGORIZATION OF PLANT AVAILABLE SOIL SILICON IN DIFFERENT RICE ECOSYSTEMS FOR EVALUATING DROUGHT AND DISEASE RESISTANCE IN RICE GENOTYPES | en_US |
| dc.type | Thesis | en_US |