Loading...
![Thumbnail Image](assets/images/Collection.png)
Theses
Browse
109 results
Search Results
ThesisItem Open Access Combined application of granular preparations of pre-emergent herbicides and fertilizers in rice(Department of Agronomy, College of Horticulture, Vellanikkara, 1995) Bindu, N K; KAU; John, P SA field experiment was conducted at the Agricultural Research Station, Mannuthy under the Kerala Agricultural University during the first crop season of 1994 to find out the effect of pre-emergent herbicides and fertilizers in rice. The experiment was laid out in a randomized block design and consisted of fourteen treatments with three replications. Broadleaved weeds and sedges dominated the field. Among broadleaved weeds, Mono choria vaginalis and sphenocleazeylanica were predomint. Shoenoplectus lateriflorus and Cyperus difformis were the prominent sedges present in the field and Echinochloa colonum,saccolepis interrrupta and Isachne miliacea were the important grasses present. Butachlor, anilofos and oxyflourfen under different methods of application reduced the weed Population. Though oxyflourfen recorded high weed control efficiency, it was highly phytotoxic to the rice crop and resulted in poor crop stand. Butachlor and anilofos applied as homemade granular (GP) preparation or as spray alone, or in combination with fertilizer was safe to the crop. The available nutrient in the soil was not affected by the different methods of application of butachlor and anilofos, alone or when combined with fertilizer. Butachlor and anilofos as spray or as GP applied alone, or in combination with fertilizer recorded similar crop growth characteristics, yield and yield attributes. Nutrient up taken by weeds was lower in butachlor and anilofos treatment. Lower weed index values were recorded in butachlor and anilofos treatment. The highest return per rupee was obtained from anilofos treatments. The highest return per rupees was obtained from anilofos treatments. In general, combined application of anilofos or butachlor GP with fertilizer gave efficient control of weed, produced higher grain yields and high return per rupee invested. It also reduced cost, energy and time of weed control operation.ThesisItem Open Access Standardisation of fertilizer schedule for export oriented production of bhindi(Department of Agronomy, College of Agriculture, Vellayani, 1993) Sajitharani, T; KAU; Pushpakumari, RAn experiment was conducted at the instructional farm, College of Agriculture, Vellayani to find out the effect of different levels of fertilizers and their split application on the growth, yield, quality and nutrient uptake of bhindi. Abelmoschus esculentus (L) Moench. The treatments consisted of four levels of nutrients Viz. (330: 110: 220 kg N2 P2O5 & K2O), the present T & V recommendation, 2/3 of the T & V recommendation, 1/3 of the T & V recommendation and 50: 8: 30 kg NP2O5 & K2O per hectare the present package of practices recommendation and 3 methods of application viz. nutrients in 2 splits, 4 splits and 6 splits. The results revealed that nutrient levels significantly influenced most of the growth and yield contributing characters and yield of bhindi. Biometric characters like plant height, LAI, CGR, DMP and yield contributing characters like days to 50 percent flowering, number of flowers formed, number of fruits formed total yield of fruits and quality parameters like protein content and ascorbic acid content increased with increasing levels of nutrients, recording their maximum value at F1 level, (T and V recommendation). Uptake of nutrients by plants, fruits and total was also maximum for the same treatment. However yield attributes viz. setting percentage, length and girth of fruits etc. remain unchanged with increasing levels of nutrients. Application of fertilizer nutrients in different splits viz. 2,4 or 6 cause significant variation in some of the growth and yield characters. An increase in the plant height at 60 DAS, DMP, days taken for 50 percent flowering and uptake of nutrients was noticed when nutrients were supplied in two equal splits, viz half as basal and half 30 DAS (S1). On the other hand the ascorbic acid content in fruits was maximum when nutrients were applied in six splits. Application of nutrients in 6 splits caused a significant reduction in the crude fibre content also. From the economic point of view, the maximum net profit of Rs.13682.54 was obtained by F3 level (2/3 of T and V recommendation) and Rs.14710.8 by S1 (2 equal splits half as basal and half 30 DAS).ThesisItem Open Access Economising nitrogen in rice production with sesbania rostrata(Department of Agronomy, College of Agriculture, Vellayani, 1992) Shalinipillai, P; KAU; Muraleedharannair, VWith a view to assessing the influence of in situ growing and incorporation of Sesbania rostrata on the growth and productivity of rice and to study the economy of nitrogen use by rice, a field experiment was conducted at College of Agriculture, Vellayani during the period from July 1991 to December 1991. The experiment was laid out in Randomised Block Design with three replications. Three levels of Rhizobium inoculation for Sesbania rostrata (i1-seed inoculation, i2 - stem inoculation, i3 – seed + stem inoculation), five levels of nitrogen to succeeding crop of rice raised after incorporation of Sesbania rostrata (n0 – no nitrogen, n1 – 25 percent of the recommended dose, n2 – 50 percent of the recommended dose, n3 – 75 percent recommended dose, n4 – 100 percent recommended dose) and one control plot of rice (treated as per KAU package of practices recommendations) were fixed as treatments. The rice variety used was Jyothi. The soil of the experimental site was sandy clay loam, medium in available nitrogen and phosphorus and low in available potassium. An abstract of the results is given below. Among the three different levels of inoculation, seed + stem inoculation was found to influence, the green matter and dry matter yields of Sesbania rostrata positively, though not significantly. The number and dry weight of root nodules and shoot nodules, nitrogen uptake, phosphorus uptake, potassium uptake, calcium uptake and magnesium uptake were not found to be influenced significantly by the different inoculation levels. From these results, it can be concluded that, the easiest method of inoculation viz. seed inoculation is sufficient for satisfactory growth and nitrogen fixation by Sesbania rostrata. The present study also revealed that the growth and nodulation of Sesbania rostrata is not satisfactory under conditions of continuous submergence, as that prevailed during the cropping period of the present experiment. Rhizobium being an aerobic bacteria might have got inhibited under the anaerobic conditions created by continuous water logging. Furthermore, the acidic condition of the soil of the experimental site might have also inhibited the activity of Rhizobium. Thus it shows that liming is absolutely necessary for the satisfactory growth of Sesbania rostrata in acid soils. Among the different treatments tried, though the control (KAU package of practices recommendations) gave the maximum yield, it was on par with the treatment comprising 50 percent of the recommended dose of nitrogen along with Sesbania rostrata incorporation. This shows that there is considerable scope for economising nitrogen by the substitution of chemical nitrogen applied to rice by Sesbania rostrata.ThesisItem Open Access Evaluation of low cost techniques in potted vegetables grown in roof gardens(Department of Agronomy, College of Agriculture, Vellayani, 1993) Roshni, C C; KAU; Geethakumari, V LA pot culture study was conducted at the College of Agriculture, Vellayani to evaluate the lowcost techniques in potted vegetables and to compare the efficiency of various techniques for economising water use in vegetables. The experiment was conducted with chilli cultivar ‘Jwalasakhi’ as test crops. The treatments included three levels of irrigation (I3-60, I2-80 and I1-100 per cent field capacity), two methods of irrigation (M1- indigenous auto irrigator using hospital drip and M2-pot watering) and three moisture conservation methods (c0-control without any conservation, C1-application of coir pith and c2-application of Jalasakhti). One absolute control viz., wick irrigation was compared with other treatments. Potting mixture prepared by mixing sand, soil and cowdung in 1:1:1 proportion by weight was used as the rooting medium. The medium was low in available nitrogen, high in available phosphorus and low in available potassium. The field capacity and permanent wilting point were 18.4 and 7.4 per cent respectively. The experiment was laid out in completely randomised design with six replications. The results of the investigation are summarised below. Plant height, branches, LAI at harvest, DMP, S: R ratio and root dry weight at different growth stages differed significantly with methods, levels of irrigation and conservation methods. All these parameters were better under wick irrigation, 100 per cent FC and coir pith mulching. Whereas drip irrigation recorded maximum LAI at initial stages and tap root length. All yield parameters like number of flowers plant-1, fruit plant -1, fruit girth, fruit volume and hundred fruit weight were better under wick irrigation followed by drip irrigation. Among the moisture regimes 100 per cent FC registered better values for all the yield attributes. Coir pith mulching top seeded with respect to these characters. Maximum yield was obtained for wick irrigation, 100 percent FC and coir pith mulching. With respect to WUE, coir pith mulching followed the same pattern as yield. Whereas drip irrigation recorded maximum WUE and 80 per cent FC resulted in higher WUE compared to the other two irrigation regimes. Uptake of N, P and K were maximum in wick irrigation and coir pith mulching. N and K uptake were maximum at 100 per cent FC, but P uptake was high at 80 per cent FC. Under all levels of irrigation, maximum yield and WUE were obtained by drip irrigation and coir pith mulching. Coir pith mulching revealed its superiority under both methods of irrigation with respect to yield and WUE. Maximum yield was obtained at drip irrigation at 100 per cent FC with coir pith mulching while maximum WUE was obtained at drip irrigation at 80 per cent FC with coir pith mulching. Maximum profit was realised by drip irrigation at 100 per cent FC with coir pith mulching. With drip irrigation and coir pith mulching 20 per cent water can be saved without much reduction in yield.ThesisItem Open Access Response of cucumber (Cucumis melo L.) to drip irrigation under varying levels of nitrogen and potash(Department of Agronomy, College of Agriculture, Vellayani, 1997) Lakshmi, S; KAU; Sasidhar, V KTwo field experiments and one observational trial were conducted in the Instructional Farm, College of Agriculture, Vellayani during 1992 and 1993 to study the effect of drip irrigation and application of N and K fertilizers on the growth and yield of cucumber. In the preliminary observation trial (Experiment I a) three levels of drip irrigation, (2, 3 and 4 I plant-1 day-1) four timings of irrigation (1, 2, 3 and 4 hours) and two number of drippers per plant (1 and 2 dripper plant-1) were evaluated and based on the results of this experiment, the number of drippers per plant and duration of drip irrigation was standardised. Experiment 1 b was conducted to standardise the method of application of fertilizers in Experiment 2 and 3 for which cucumber plants raised under different levels of drip irrigation (2, 3 and 4 I plant-1 day-1). This was conducted during April 1992. The results of these experiments indicated the duration for drip irrigation as 3 hours per day and one number of dripper per plant to be the best. The spread and depth of root system of cucumber plants raised under drip irrigation pointed out that the fertilizers as a ring around the base of the plant at a distance of 20 cm will be within the root zone of the plant. The experiments 2 and 3 were laid out in the field with three levels of drip irrigation (2, 3, and 4 I plant-1 day-1), three levels of nitrogen (35, 70 and 105 kg ha-1) with three levels of potassium (25, 50 and 75 kg ha-1) with three drip irrigation controls (2, 3 and 4 I plant-1 day-1) and farmer's practice. The yield of cucumber was highest at the drip irrigation level of 31 planr-1 day-1. Irrigation at this level favourably influenced the vegetative characters, yield attributes and yield. But root dry matter was not influenced by the different drip irrigation level while the root spread and root depth were highest at the drip irrigation level of 41 plant-1 day-1. When different levels of nitrogen applied were observed, the vegetative characters yield attributes and yield were found to be favourably influenced at 70 kg N ha-1. The root spread of cucumber was highest at the highest level of N applied (l05 kg ha-1). Potassium at 50 kg ha-1 produced the highest yield due to its favourable influence on the vegetative and yield characters. There was no influence of potassium on my of the root characters studied. The soil moisture status was highest up to 30 cm depth in all drip irrigated treatments while in pot watered plots, the soil moisture was higher in the lower layers below 30 cm. The field water use efficiency was highest at the drip irrigation level of 3 I plant-1 day-1, 70 kg nitrogen ha-1 and 50 kg potassium ha-1. The nitrogen, phosphorus and potassium uptake by the plants and fruits were highest at the drip irrigation level of 31 plant day I, 70 kg N ha-I and 50 kg K ha-I. The physical optium levels of drip irrigation was 31 plant -1 day -1, 93 kg N ha-1 and 65 kg K ha-1 in the first season. When another crop is repeatedly grown in the same field, the Nand K levels can be reduced to 75 kg ha-1 and 60. kg ha-1 but drip irrigation is required at the rate of 31 plant-1 day-1. This resulted in higher benefit cost ratio of 2.83 and internal rate of returns of 23%. The payback period of this project worked out to 1.13 years.ThesisItem Open Access Soil test crop response studies in cassava in laterite soils of Kerala(Department of Agronomy, College of Agriculture, Vellayani, 1997) Kumari Swadija, O; KAU; Sreedharan, CAn investigation was undertaken at the College of Agriculture, Vellayani to establish soil test crop response correlation for soil test based balanced fertilizer prescription for cassava var. M-4 in laterite soils of Kerala. The field investigation consisted of fertility gradient experiment, STCR experiment and technology verification trial. The fertility gradient experiment was conducted during April- May 1994 in the Instructional farm, Vellayani. The desired gradient in soil fertility was created in one and the same field by applying graded doses of N, P and K fertilizers and raising fodder maize var. African Tall. The STCR experiment was conducted in the same field during June '94-March '95 using the test crop, cassava var. M-4. The treatments consisted of factorial combinations of four levels of N (0, 50, 100 and 150 kg ha-1), three levels of P (0, 50 and 100 kg P2O5 ha-1) and five levels of K (0, 50, 100, 150 and 200 kg K20 ha-1) along with three levels of farmyard manure (0, 6.25 and 12.50 t ha-1) fitted in a response surface design. Using multiple regression model, the fertilizer adjustment equation for N at varying soil test values for available N for maximum tuber yield (t ha-1) of cassava in laterite soil was derived as FN = 136.6 - 0.2 SN where FN is fertilizer N (kg ha-1) and SN is soil available N (kg ha-1). The equation becomes FN = 136.6 - 0.2 SN - R for economic tuber production where R is the ratio of cost of one kg of fertilizer N to price of one kg of tuber. At varying soil test values for organic carbon% (OC) the above equations become FN = 226.13 - 378.13 OC for maximum tuber yield and FN = 226.13 - 378.13 OC - 1.25 R for economic tuber yield. The behaviour of fertilizer P and K was found to produce responses other than 'normal' and hence optimisation could not be done for fertilizer P and K for maximum and economic tuber yield at varying soil test values. The nutrient requirements of cassava var. M-4 were estimated to be 6.58, 2.37 and 6.28 kg N, P2O5 and K2O respectively to produce one ton of tuber. In the laterite soil, the efficiencies of contribution of nutrients from the soil for cassava were calculated as 40.17, 41. 3 3 and 48.60% N, P2O5 and K2O respectively. The fertilizer efficiencies were worked out as 54.38, 47 and 52.650% N, P2O5 and K2O respectively. The efficiencies of contribution of nutrients from farmyard manure were calculated as 78.24, 57.33 and 69.66%) N, P2O5 and K2O respectively. From the above basic data, fertilizer prescription equations for specific yield targets of cassava var. M-4 in the laterite soil were derived as given below. Without FYM FN = 12.10 T - 0.74 SN FP2O5 - 5.04 T - 2.02 SP FK2O = 11.93 T - 1.10 SK With FYM FN = 12.10 T - 0.74 SN - 1.44 ON F P2O5 - 5.04 T - 2.02 SP - 2.79 OP FK2O = 11.93 T - 1.10 SK - 1.58 OK where FN, F P2O5 and FK2O are fertilizer N, P2O5 and K2O respectively in kg ha-1, T is the target of tuber yield in t ha-1, SN, SP and SK are soil available N, P and K in kg ha-1 respectively and ON, OP and OK are quantities of N, P and K supplied through organic manure in kg ha-1 The technology verification trial was undertaken during June '96-March. '97 in the laterite soil in three farmers' fields in Thiruvananthapuram district and also in the Instructional Farm, Vellayani. The treatments consisted of Package of Practices recommendation for fertilizer, fertilizer recommendation by the Soil Testing Laboratory and fertilizer doses for the yield targets of 15, 20 and 25 t ha-1 along with a uniform dose of 6.25 t ha-1 of farmyard manure for all treatments. The fertilizer doses based on targeted yield equations recorded higher tuber yield and net income, benefit cost ratio and net returns per rupee invested over the fertilizer recommendation by the Soil Testing Laboratory and Package of Practices recommendation emphasising the need for site specific recommendation based on soil tests. The yield targets of 15 and 20 t ha-1 recorded more than cent per cent achievement and the yield target of 25 t ha-1 recorded about 90% achievement. Higher tuber yield, benefit cost ratio and net returns per rupee invested could be achieved for the yield target of 20 t ha-1. The fertilizer dose for the yield target of 15 t ha-1 recorded the highest returns per rupee invested on fertilizers. The study has revealed the superiority of fertilizer application based on targeted yield approach over the semi-quantitative approach employed in the soil testing laboratories and generalised state level Package of Practices recommendation for the crop. In this approach, the fertilizer dose can be adjusted in accordance with the specific objective and available resources of the farmer.ThesisItem Open Access Development of subsurface pad irrigation system for tomato(Department of Agronomy, College of Agriculture, Vellayani, 1995) Abdul Nassar, K; KAU; Jaikumaran, UAn experiment was conducted in the summer rice fallows of the Agricultural Research Station, Mannuthy during 1995 to develop and test subsurface pad irrigation system for tomato and to compare it with surface irrigation. The soil was sandy clay loam, medium in organic carbon and available potassium and high in available phosphorus. The eight treatments comprised of combination of four frequencies of irrigation (IW/CPE ratios of 1.2, 0.9, 0.6 and 0.3) and two irrigation systems (subsurface pad irrigation and surface irrigation). The experiment was laid out in randomized block design with three replications. Poly bags filled with saw dust placed 45 cm beneath the surface at the frequency of one pad for every four plants formed SSPI. Water was supplied to pads by laterals supplying 40 mm of water per irrigation. The study revealed that tomato responded very well to irrigation. Biometric characters like plant height, number of leaves and leaf area index and yield attributing characters like number of flowers, number of fruits and total weight of fruits per plant were favourably influenced by frequent irrigation under both the systems of irrigation. The fruit yield increased with frequency of irrigation and maximum at the IW/CPE ratio of 1.2. The plants irrigated by surface method grew taller, had more leaf area index, produced more number of green leaves, flowers, fruits and total fruit weight per plant compared to the plants irrigated under SSPI system at the irrigation frequencies of IW/CPE ratios 1.2, 0.9, and 0.6. But at the IW/CPE ratio of 0.3, the subsurface irrigated plants performed better than the surface irrigated plants both in terms of growth and yield attributing characters. The crop receiving irrigations through SSPI systems consumed lesser amount of water at all the frequencies of irrigation compared to surface method. This decline at the IW/CPE ratios of 1.2, 0.9, 0.6 and 0.3 were to the tune of 22,30,40 and 18 per cent respectively. The soil moisture extraction from 0-15, 15-30 and 30-60 cm layers in SSPI was 62-70, 24-29 and 6-12 per cent respectively whereas in surface irrigation the respective values were 62-64, 22-23 and 13-15 per cent. The soil moisture redistribution was rapid in the case of surface irrigation whereas it was gradual in the case of SSPI. Moisture content in the case of SSPI was maximum at the radial distance of 15 cm from the pad on either sides whereas in surface irrigation there was no remarkable difference in the moisture content with respect to radial distance from the plant.ThesisItem Open Access Influence of date of sowing and levels of irrigation on the growth and yield of water melon (citrullus lanatus) grown in rice fallows(Department of Agronomy, College of Horticulture, Vellanikkara, 1993) Siby Neendissery, T; KAU; Balakrishna Pillai, PAn experiment was conducted at the Rice Research Station, Mannuthy, Thrissur during the period from November 1990 to April 1991 to study the influence of date os sowing and levels of irrigation on the growth and yield of watermelon (Citrullus lanatus) grown in rice fallows. The experiment was laid out in split plot design with three replications. The treatment consisted of seven dates of sowing (November Ist, November 16th, December 16th, December 32st, January 15th and January 30th) in the main plot and four levels of irrigation (IW/CPE ratio of 1.0, IW/CPE ratio of 0.75, IW/CPE ratio of 0.50, pot watering -1 pot per day per pit) in the sub plot. Observations on various morphological characters, flowering and yield attributes were recorded during the course of investigation. Soil moisture observations were taken before, and 24 hours after irrigation to compute consumptive use and soil moisture depletion. The daily values of various weather elements recorded at the meterological observatory were collected to work out the crop weather relationship. The plants irrigated daily (10 litre/pit/day) were superior to others with regard to vine length, date of picking maturity, date and number of male and female flower production, number of fruits, fruit girth, weight, yield and total dry matter production, but was on par with IW/CPE ratio of 1.0. Irrigation at IW/CPE ratio of 1.0 was superior with regard to the number of nodes for female flower production and number of seeds per fruit. Irrigation treatment IW/CPE ratio of 0.50 recorded the highest sex ratio, hundred seed weight and T.S.S. content. The crop sown on November 16th was superior to others with regard to most of the crop characters. The crop weather relationship studies showed that the temperature range during flowering and early fruit development (3rd to 7th week), maximum temperature during fruit development (7th to 10th week) and relative humidity during maturity (11th to 13th week) negatively correlated with yield. While for total dry matter production there was a negative correlation between temperature range during flowering (3rd to 5th week), maximum temperature during fruit development and early maturity (8th to 11th week) and relative humidity during maturity (11th to 13th week). It was found that irrigation and sowing date has a significant effect on overall growth and yield of the crop. The highest yield was recorded in crop sown on November 16th irrigated daily (10 litre/pit /day). The best performance may be attributed to the optimum weather conditions during the crop period and the effective utilisation of water. From the soil moisture studies it is evident that the consumptive use increased with the frequency of irrigation. The top 15 cm of the soil layer accounted for the highest soil moisture depletion. The depletion was more from the deeper layers in the drier regimes. The water use efficiency was highest for the plants irrigated at IW/CPE ratio of 0.5. sown on November 16th. Results of the present experiment indica that at Mannuthy and surrounding water melon can be successfully raised in rice fallows if irrigated daily (10 litre/pit/day.) and sown in the middle of November.ThesisItem Open Access Nutrient management for intercropped colocasia esculenta var thamarakannan(Department of Agronomy, College of Agriculture, Vellayani, 1993) Rajasree, J; KAU; Oommen, MField experiments were conducted at the Instructional Farm, College of Agriculture, Vellayani to study the effect of nitrogen and potassium on growth and yield of Colocasia and uptake pattern of major nutrients under open and intercropped situations in coconut gardens. The treatments in the experiment consisted of a combination of three levels of N) 40, 60 and 80 kg/ha) and three levels of K (80, 120 and 160 kg/ha). The experiment was laid out in 32 factorial RBD. Different growth attributes like plant height, number of leaves plant-1and LAI were maximum when N @ 60 kg/ha and K @ 160 kg/ha were applied under open condition. Under intecropped situations N @ 40 kg/ha and K @ 160 kg/ha recorded the maximum values for these characters. The yield attributes viz., number of cormels/plant, mean weight of cormels, cormel and corm yield/plant, and harvest index gave maximum values when N @ 60 kg/ha and K @ 160 kg/ha were applied under open condition. In the intercropped situation, the highest values were obtained when N and K were applied @ 40 and 160 kg/ha. Nitrogen @ 60 kg/ha and K @ 160 kg/ha gave the highest yield of marketable tubers under open condition while K @ 160 kg/ha gave the maximum yield under intercropped situation. Nitrogen had no influence on yield of marketable tubers under intercropped situations. Pottasium application increased the starch percentage of tubers and 160 kg K/ha resulted in the maximum value under open and intercropped situations. Plant uptake of N, P and K were influenced by increasing levels of K and was highest at the highest level of K in both open and intercropped situations. Available N and P content of the soil was not influenced by N and K levels under open condition, while the available K was maximum when 160 kg/ha was applied in both open and intercropped situations. Maximum benefit cost ratio and net returns were obtaining by the application of N and K @ 60 kg/ha and 160 kg/ha respectively under open conditions and 40kg/ha and 160 kg/ha respectively under intercropped situation with coconut.