Theses

Browse

Search Results

Now showing 1 - 9 of 10

Open Access
Vermicompost as a potential organic source and partial substitute for inorganic fertilizers in sweet potato (Ipomoea batatas (L.) Lam.)
(Department of Soil Science and Agricultural Chemistry,College of Agriculture, Vellayani, 1998) Suresh Kumar, S N; KAU; Ushakumari, K
An investigation entitled "Verrnicompost as a potential organic source and partial substitute for inorganic fertilizers in sweet potato (Ipomoea batatus (L) Lam)" was carried out at the Instructional Farm, College of Agriculture, Vellayani during the period December 1995 to April 1996. The main objectives of the study were to study the efficiency of vermicompost as an organic manure, the extent to which inorganic fertilizers can be substituted when vermicompost was used as an organic source and the feasibility of reducing the dose of vermicompost. The experiment was laid out III randomised block design with seven treatments and four replications. The treatments consists of package of practices recommendations of Kerala Agricultural University for sweet potato (cattle manure + inorganic fertilizers) and vermicompost as organic source with graded doses of inorganic fertilizers. The growth parameters like vine length and number of branches did not show any significant variation. However highest vine length and number of branches are noticed in treatment which received vermicompost as a sole source of nutrient. Significant difference was observed in vine yield and highest vine yield was obtained when vermicompost was given as a sole source of nutrients. Yield attributing characters like length and girth of tubers and number of tubers did not show any significant variation. With respect to mean tuber weight and tuber bulking rate, the treatment differed significantly and maximum effect was observed when vermicompost was applied along with half the recommended dose of inorganic fertilizers. Significant treatment effect could be observed in total tuber yield and marketable tuber yield. Vermicornpost with half or 3/4th NPK produced highest yield. From this it could be deduced that by using vermicompost as organic manure in sweet potato, it is possible to bring down the usage of chemical fertilizers. Half or 3/4th dose of vermicompost along with recommended dose of inorganic fertilizers was equally effective as that of package of practices recommendations of Kerala Agricultural University (cattle manure + recommended inorganic fertilizers) in yield and yield attributes of sweet potato. The nitrogen and phosphorus content in the leaves and vmes did not show any significant difference by applying various treatments. But in tubers the nitrogen content was maximum when 1/2 inorganic fertilizers + organic manure as vermicompost was applied. The phosphorus accumulation in tuber was maximum in the combination of full inorganic fertilizers + organic manure as cattle manure was given. The treatment combination of full inorganic fertilizers + organic manure as vermicompost resulted m maximum accumulation of phosphorus in leaves, vines and tubers. Regarding calcium, magnesium and iron contents of leaves, vines and tubers there was no significant difference among various treatments. The application of full inorganic fertilizers + organic manure as vermicompost produced maximum manganese concentration in leaf and tuber. The starch content of tubers showed a decreasing trend with the reduction in the quantity of inorganic fertilizers. But by reducing inorganic fertilizer levels, the reducing sugar percentage increased. The crude protein, crude fibre and carotene contents showed the same trend as that of reducing sugar. The plant uptake of nitrogen, phosphorus and potassium was maximum when 112 inorganic fertilizers + organic manure as vermicompost was applied. The organic carbon level after the crop showed significant difference among various treatments. The maximum organic carbon percentage was noticed when nitrogen as vermicompost + organic manure as vermicompost was given. The growth characters like vine yield, number of branches were negatively correlated with yield. The yield components like number of tubers per plant, tuber weight, uptake of nitrogen, phosphorus and potassium showed positive correlations with yield. The economics worked out show that the highest net profit was obtained when 1/2 inorganic fertilizers + organic manure as vermicompost was given. The cost of cultivation while applying this treatment was minimum and it showed a B C ratio of 2.53.
Open Access
Effect of vermicompost enriched with rock phosphate on cowpea
(Department of Soil Science and Agricultural Chemistry,College of Agriculture, Vellayani, 1999) Sailajakumari, S; KAU; Ushakumari, K
An investigation was carried out at the College of Agriculture, Vellayani during 1998 to evaluate the effect of vermicompost enriched with RP on P availability yield and quality of cowpea and the feasibility of reducing the inorganic P. The variety used was Kanakamoni. All the growth characters, yield and yield attributes studied were significantly influenced by different treatments. Nodule number per plant, weight of nodules per plant and root shoot ratio were maximum by the application of enriched vermicompost. Yield attributes like number of pods per plant, number of seeds per pod and hundred seed weight and total grain yield were significantly increased by the application of enriched vermicompost. Vermicompost primed with full RP or with half RP produced no significant difference in grain yield. Thus the results revealed that inorganic phosphoate for cowpea coufd be reduced to half• of its recommended dose by priming vermicompost with RP. Analysis of plant samples at harvest showed that maximum content of macronutrients except Mg was recorded by enriched vermicompost. It showed its superiority over other treatments for protein and P content of grain. Enriched vermicompost also registered significant increase in soil available N, P and K after the experiment. ./ 2 Uptake of macronutrients was significantly influertced by different treatments. Enriched vermicompost registered maximum mean value for the uptake of all the macro nutrients. Priming of vermicompost with full RP or with half RP produced no significant difference in uptake of any macro or micronutrients. Grain yield was positively and significantly correlated with the growth characters. Yield and yield attributes showed positive and significant correlation with nutrient uptake. The study indicated the superiority of vermicompost enriched with RP on yield and quality of cowpea. P recommendation for cowpea can be reduced to half by priming vermicompost with RP.
Open Access
Assessment of some phosphatic sources for possible accumulation of heavy metals in chilli (Capsicum annuum L.)
(Department of Soil Science and Agricultural Chemistry, College of Horticulture, Vellanikkara, 1998) Jidesh, C V; KAU; Sam, T Kurumthottical
Rock phosphate sources collected from different locations were analysed for both phosphorus content and heavy metals namely cadmium and lead. Those sources which analysed relatively higher content of heavy metals were included for conducting a pot culture experiment using chilli (Capsicum annuum L.) as test crop. To derive meaningful comparison in the study, partially acidulated rock phosphates as well as direct water soluble source of cadmium and lead were also applied to assess their bioavailability to plants. The influence of organic matter when applied alone or in conjunction with heavy doses of heavy metals was also assessed in the study. The pot culture experiment was conducted in the Vegetable Research Farm, Department of Olericulture, Vellanikkara during the kharif season of 1996, with chilli as the test crop. The entire fertilizer management was based on package of practice (N, P and K at 70, 40 and 25 kg ha-1) recommendation. Five different sources of P selected for the pot culture experiment were (1) Maton rock phosphate, (2) Mussorie rock phosphate, (3) Gafsa rock phosphate, (4) Rajasthan rock phosphate and (5) Single superphosphate. The maximum content of cadmium (55 mg kg-1) was recorded in Gafsa rock followed by 25 mg Cd kg-1 for the Maton rock and single superphosphate analysed the least concentration of cadmium (15 mg kg-1 Highest lead content of 230.5 mg Pb kg-1 was analysed in Maton rock while lowest (38 mg kg-1) in Musoorie rock. All the other sources maintained their heavy metal concentration in between these extremes. In general, the shoot portion of test crop chilli recorded highest cadmium uptake while root portion noted the maximum lead uptake. The least uptake of heavy metals was noted in the chilli fruit, which is the edible part of the plant. This indicates that the heavy metal load in the fruit portion is much less when compared to other plant parts, irrespective of the sources used. The same trend was evident when either partially acidulated P sources or direct source of heavy metals (through water soluble salts) were applied. However, the uptake of cadmium and lead from those sources remained higher in plant parts. Application of organic matter in conjunction with a heavy dose of heavy metals to soil resulted in a significantly higher uptake of cadmium and lead in all plant parts. Analysis of the available cadmium and lead in the post-harvest soil samples indicated negligible build-up of these metals in soils. However, direct application of higher levels of heavy metals permitted higher cadmium and lead extraction in the post-harvest soil samples. Application of partially acidulated rock sources to soils, though could cause enhanced uptake of heavy metals, could not show higher residual effects of heavy metals in post-harvest soil samples.
Open Access
Regulation of major plant nutrients and organic matter for improving the nutritive quality of banana grown in laterite soils
(Department of Soil Science and Agricultural Chemistry, College of Horticulture, Vellanikkara, 1999) Binu Thomas; KAU; Hassan, M A
An investigation was taken to study the regulation of major plant nutrients and organic matter for improving the nutritive qualities of banana. The expriment was laid out at Banana Research Station, Kannara, Kerala Agricultural University during the period 1996-97. The result of this study revealed that application of fertilizer and organic matter is essential for getting better yield and quality of banana. All the food nutrients studied were increased by the application of fertilizer and hence the quality is much improved. Regarding bunch yield the fertilizer dose of 12.5 kg FYM, 200: 125:300 g N, P205 and K20 per plant obtained maximum yield. The treatments receiving medium level of FYM and nitrogen recorded higher content of carbohydrate. Protein content of banana was increased by the application nitrogen and potassium. Application of farmyard manure enhanced the fat content of banana. Sugar content of the banana fruit is increased by the application of nitrogenous and potassium fertilizers. Acidity is increased by the application of farmyard manure and nitrogen. Nitrate accumulation in banana was high in plots receiving highest dose of nitrogen. Nitrogenous fertilizers increased the carotene content of banana. Fertilizer application enhances the total mineral content of banana due to increased uptake and availability of nutrients. Fibre content was high in fertilized plots compared to absolute control. The nitrogen content of edible portions of banana was high in plots receiving higher doses of nitrogen. The treatment T6 and T\3 which received highest dose of phosphorus (200 g/plant) recorded highest content of phosphorus. Vitamin C content was enhanced by the application of nitrogenous fertilizer and farmyard manure. Correlation studies revealed that the content of l1ajor nutrients in soil at 2, 4 and 6 months after planting has got much influence on the quality parameters studied. Hence fertilizers should be applied in split doses commencing from 2 months after planting. Path coefficient analysis revealed that the direct effect of the three major nutrients on quality parameters was maximum at 6 months after planting. The direct effects at 2 months after planting and 4 months after planting were also significant. This indicated that the requirement of these nutrients is essential through out the growth of the plant.
Open Access
Comparative study of soils of cardamom plantations and virgin forests
(Department of Soil Science and Agricultural Chemistry, College of Agriculture, Vellayani, 1998) Gladson, D` Cruz; KAU; Babukutty, K
The investigation entitled "comparative study of the soils of cardamom plantations and virgin forests" was taken up at the College of Agriculture, Vellayani, during 1994 - 96. The study has been made on the soils of cardamom plantations of the Idukki district of Kerala with a view to assess and compare physico-chemical and nutritional status of cardamom cultivated soils and virgin forests. A comparison was also made between healthy cardamom plantation with those where a decline in yield is observed. For this, surface soil samples and soil profiles excavated from various selected locations were subjected to detailed chemical analysis. The plant samples were also collected from the cardamom plantations and subjected to chemical analysis to find out whether any plant nutrient factors are involved in the yield decline in cardamom. A study of the soils of cardamom plantations in comparison with adjacent forests has shown that considerable variation in the physico-chemical properties of the forest soils did not take place due to the influence of the cardamom plantations. In all these soils, the sand and silt content decreased and clay content increased with depth. The soils of cardamom plantations have higher sand content and lower clay content compared to the soils of adjacent forests. A higher content of the clay in the forest soils compared to cardamom plantation indicates a greater degree of weathering and clay formation. Healthy cardamom plantation soils contained a significantly higher amount of coarse sand and lower content of fine sand than the soils of the location which show a decline in yield. 12D The physical properties such as bulk density, particle density and WHC and exchangeable properties such as CEC, ECEC, exchangeable acidity were found to be positively influenced by organic matter content of the soils and were . more or less similar in all the locations. Total P and K content of soils of the cardamom plantations were lowwhen compared to the adj acent forest indicates inefficient bio-cycling associated with the cardamom plantation and loss of bases from the system by leaching and soil erOSIOn. A lower P content of the soils of the cardamom plantation which show a decline in yield when compared to the healthy plantation is due to t,he inherent properties of the former. Inspite of the similarity in the content of total nitrogen, the available N of the adjacent forest soils was significantly higher indicating a rapid rate of mineralisation of organic matter in the soils of adjacent forest. The total P content of the soils of the healthy cardamom plantations was significantly higher than that of the location which show a decline in yield.~\.Jhe specific influence of --' the plantations m making more of available P from the unavailable pool is evident. The total and exchangeable potassium status m the soils of the cardamom plantation recorded a lower value than the soils of the adjacent forest. This situation may indicate a lower release as well as grater uptake of this element. The content of micronutrients such as Fe, Mn, Zn and Cu were more or less same in the soils of cardamom plantation and adjacent forest indicating the same parent material and similar climatic conditions prevailed in the locations under study. The analysis of plant leaves showed a higher content of P, K, Ca, Mg, Fe, Mn, Zn and Cu in the leaves of the healthy cardamom plantation. This point to a situation where the soil nutrient factors are not a single factor for declining the yield of cardamom but the plant nutrient factors were also responsible for the decline in yield. 1:Z t
Open Access
Forms, availability and transformation of potassium in laterite soils as influenced by crop uptake
(Department of Soil Science and Agricultural Chemistry, College of Horticulture, Vellanikkara, 1998) Nicy Thomas; KAU; Gopi, C S
An investigation was taken up to study the fate of applied and native potassium in a laterite soil as influenced by other major nutrients and organic matter and uptake by an annual crop, banana. The experiment was laid out at Banana Research Station, Kannara, Kerala Agricultural University during the period 1996- 1997. The result of the study revealed the necessity of fertilization of the field/soil for better yield. The maximum content and uptake of nutrients N, P and K occurred during the early and late vegetative stages of banana. Hence fertilizers should be applied for the crop from 2 months after planting onwards and continued up to six months after planting. Correlation studies revealed the significant relationship of total K in the soil with yield at different stages. Also poistive correlation between the exchangeable K content in the soil and yield was established. Path coefficient analysis revealed that the direct effect of total K content in the soil on yield was highest at P4 (6 MAP). The indirect effect was maximum at P4 (6 MAP) through P3 (4 MAP). The exchangeable K also was found to have positive direct effect on yield. The indirect effects were not significant. Water soluble K at different stages showed a direct effect of comparable magnitude on yield.
Open Access
Effect of soil and foliar application of vermiwash on growth , yield and quality of tomato
(Department of Soil Science and Agricultural Chemistry,College of Agriculture, Vellayani, 1999) Rani, Jasmine; KAU; UshaKumari, K
An investigation was carried out at the Instructional Farm attached to the College of Agriculture, Vellayani in two experiments to find out the effect of soil and foliar application of vermiwash on growth, yield and quality of tomato. First one was a pot culture experiment in completely randomised design to find out the best concentration among the different treatments. Based on fruit yield, treatments were selected and field experiment was carried out in factorial RBD. The treatment factors were two methods of application t .. (m. and m-), four concentrations of vermiwash (Vo, VI, V2 and V3) and three levels of inorganic fertilizers (fl, f2 and f3). The fruit yield of pot culture experiment revealed that the highest concentration of vermiwash (100 %) produced the lowest yield among the different concentrations of vermiwash. Soil and foliar application produced similar results. Field experiment was carried out without the highest concentration (100 %) of vermiwash. The results revealed that significant difference in the fruit yield of tomato was obtained. Application of vermiwash along with inorganic fertilizers produced marked increase in fruit yield. At higher concentrations (50 and 25 %) of vermiwash, inorganic fertilizers could be reduced to half of the recommended dose without any yield reduction. It was also observed that at higher concentration, foliar spraying was found to be better whereas at lower concentration soil application was more effective. But vermiwash application did not produce any influence on the number of days to flower, fruit - size, dry weight and root - shoot ratio. Vermiwash application through the foliage along with inorganic fertilizers resulted in a higher seed yield. Soil application of vermiwash produced fruits with more shelf - life. The different concentration of vermiwash produced positive influence on the lycopene content of tomato, but no influence on the ascorbic acid and crude fibre content. Nutrient content of plant and fruits were influenced by the vermiwash application. Plant uptake of major and micronutrients was maximum for the highest concentration of vermiwash applied through foliage along with fUll inorganic fertilizers. The present study revealed that vermiwash application in conjunction with inorganic fertilizers could increase the yield and the quality parameters of fruits of tomato.
Open Access
Nutrient economy through seed coating with vermicompost in cowpea
(Department of Soil Science and Agricultural Chemistry, College of Agriculture, Vellayani, 1998) Meera, A V; KAU; Prabhakumari, P
An investigation was carried out at the Instructional Farm, attached to the College of Agriculture, Vellayani to evaluate "Nutrient economy through seed coating with vermicompost in cowpea". The experiment was laid out in Completely Randomised Design with nine treatments and three replications. The variety used was Kanakamoni. The treatments include coating of seeds with Rhizobium, vermicompost and a combination of both and also uncoated seeds supplied with either farmyard manure or vermicompost as organic source. Biometric observations like height of plant, number of leaves, seedling girth and number of fruiting branches were not significantly influenced by any of the treatments. However, root characters like root length, root spread and number of effective nodules were found to be significantly influenced by the different treatments. Coating of seeds with vermicompost significantly influenced the grain yield of cowpea and also the number of pods plant-l. Coating seeds with vermicompost combined with the application of full inorganic fertilizers and farmyard manure as organic source recorded the highest grain yield. From the analysis of grain samples, it is inferred that only K and Ca content of grain was significantly influenced by the different treatments. Phosphorus solubilisation capacity of soil was not significantly influenced by any of the treatments. N fixing capacity of soil was significantly influenced by the vermicompost coating of seeds during 30 DAS and 45 DAS. Soil analysis for available nutrients revealed that the different treatments had significant influence on the Ca, Mg, Zn, Cu and Mn content in soil. Use of vermicompost coated seeds produced the maximum uptake of N, P and K at maximum flowering stage and at harvest. Soil application of vermicompost recorded the highest uptake of Ca, Mg, Cu and Mn during maximum flowering stage. Plant analysis for nutrient content indicated that the content of all the nutrients except P was significantly influenced by the different treatments during maximum flowering stage. Yield was positively and significantly correlated with the height of plant, root characters and availability and uptake of nutrients. In the present study, a superiority is shown by vermicompost inoculated plants where farmyard manure was given as the organic source indicating that at times of scarcity of vermicompost, seed treatment could serve the purpose.
Open Access
Standardisation of soil sampling and fertilizer recommendation techniques for coconut gardens
(Department of Soil Sciences and Agricultural Chemistry, College of Horticulture, Vellanikkara, 1998) Nimba Frango, E F; KAU; Gopi, C S
An investigation was carried out during 1994-95 to standardise soil sampling technique for coconut and to work out fertilizer recommendation system considering physical/textural nature of soil as well as nutrient levels. Two standing populations of WeT palms grown under good and average management practices (situation A and B respectively) located at Mulamkunnathukavu (Thrissur district) was utilised for the study. From each plot twenty healthy palms were selected for the study. The coconut gardens were separated by a distance of about 1 km and the soil of the site was laterite (Oxisol). Composite soil samples were collected from three depths from the surface and from three radial positions from the bole of the palm. Samples were collected in May, October and January. Leaf samples were collected from the 10th frond and observations on yield and yield attributes were also recorded along with soil samples. Physico-chemical properties of soil, root activity pattern, leaf nutrient content and yield and yield attributes of both situations were compared. Correlation between physical and chemical properties of soil, correlation between soil parameters, leaf nutrient content, yield and yield attributes were also worked out. Both situations showed much variation in physico-chemical properties of soil. Coarser soil fractions were more in situation B while, in situation A finer fractions dominated. High yield situation (situation A) recorded higher values for organic carbon and available K compared with situation B. Depthwise as well as radial distance wise differences were also noticed in the nutrient content. In both situations soil nutrient content decreased as the sampling depth from the surface as well as radial distance from the bole of the palm increased. A perusal of seasonal variation of nutrients in soil indicated that maximum organic carbon, available P and available K content was attained in the second season (in October) which declines continuously through the third and first season except organic carbon of situation B. Comparison of leaf nutrient status of two situations revealed that palms of situation A recorded higher N, P and K content in their leaves. Corresponding differences were also reflected in the production of nuts. Root fractions collected from different depths have indicated that in both situations maximum root activity was confined to a depth of 0-30 cm. Hence conventional method of fertilizer recommendation based on soil testing now practised in the state is not suitable for coconut which takes into account the nutrient status of the top 15 cm layer only. Comparing the radial distance L, established significant relationship only with N while L2 established significant relation with N and K. Since> 75 per cent of the roots are residing inside the basin, sampling from outside the basin alone (L3) is also misleading. Hence mixed composite sampling (L2) including both inside and outside basin soils is more appropriate. Based on the above observations the most suitable sampling technique for coconut is composite sampling containing both inside and outside basin soils from a depth of 0-30 cm from the surface (L2D2). In situation A organic carbon manifested maximum relationship to yield of nuts in the second season and potassium content in the third season whereas organic carbon content of the first season was related with yield in high yield situation. This would suggest that time of sampling is also important which differ between yield group and nutrient to be analysed . . Results also indicated that organic carbon content was related to soil fractions in both situations though, the relationship was in opposite direction. In situation A, finer fractions showed positive and coarser fractions showed negative correlations with organic carbon. The reverse was the case in situation B where coarser fraction had positive and finer fraction had manifested negative relations. It has also been noticed that organic carbon content was linked with nut production in both situations. Varying interaction of organic carbon with different fractions of soil on one side simultaneously with its direct bearing on productivity would point out to the necessity of evolving texture linked indices to get reliable information about nutrient availability status of soil. Therefore, some correction factor should be added to soil test values to account the anomalies caused by the coarser soil fraction which is not having a direct role in production and productivity.

Theses

Browse

Thesis Type

Type

Author

Date

Subject

Search Results