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199211
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Subject: Agronomy × Author: KAU × End date: 1992 × Start date: 1992 × Type: Thesis × Thesis Type: M.Sc ×
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    ThesisItemOpen Access
    Economising nitrogen in rice production with sesbania rostrata
    (Department of Agronomy, College of Agriculture, Vellayani, 1992) Shalinipillai, P; KAU; Muraleedharannair, V
    With 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.
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    ThesisItemOpen Access
    Rhizobium inoculation and nutrient levels on nodulation and seedling growth in tree legumes
    (Department of Agronomy, College of Agriculture, Vellayani, 1992) Ragini, R; KAU; Achuthan Nair, M
    An investigation entitled Rhizobium inoculation and nutrient levels on nodulation and seedling growth in tree legumes was carried out at College of Agriculture, Vellayani during August 1990 to July 1991. The investigation was carried out as three separate experiments. The main objective of Experiment I was to determine the effect of different scarification methods on the germination of some commonly grown and newly introduced legumes, the objective of Experiment II was to screen out the best among the native and exotic isolates of Rhizobium with different levels of phosphorus on the nodulation and seedling growth and the objective of Experiment III was to study the effect of Rhizobium inoculation, and nutrient levels on nodulation and seedling growth of tree legumes. The experiment (s) were carried out in a completely randomized design with five, three and four replications each for Experiments l, ll and lll respectively. Hot water treatment for three minutes was found to be effective for enhancing the germination in Acacia mangium, Paraserianthes falcataria and Sesbania grandiflora. Treatment with Con.Hcl for one minute recorded highest germination per cent in Cassia fistula. Germination percentage of 98.27 was recorded with Con.HNO3 treatment for 10 inutes. In Acaci’s Acacia Catechu and Cassia javanica maximum germination was obtained with Con.H2 SO4 treatment for five minutes, while that for one minute resulted in highest germination in Albizia moluccana. Exotic isolates, TAL 1868 and TAL 45 wire proved to be the best among the rhizobial isolates for Acacia and Albizia sp. Respectively with respect to growth and nodulation characterstics as compared to the local strains. Plant height, shoot dry weight and root dry weight were significantly influenced by phosphorus application. Nodule number per plant had increased from 0.67 to 1.33 in Acacia Arabica. Nitrogen application along with inoculation significantly influenced growth characters such as plant height, shoot dry weight and root dry weight. Maximum plant height was recorded due to application of nitrogen upto 20 kg ha-1 in Acacia Arabica and Acacia Catechu. Nitrogen application upto 20 kg ha-1resulted in highest shoot dry weight and root dry weight in both Acacia Catechu and Paraserianthes falcataria. Application of nitrogen did not increase nodule number per plant in all the tree species. However, nodule dry weight per plant increased with application of nitrogen up to 20 kg ha-1. Phosphorus application up to 50 kg ha-1 produced maximum shoot and root dry weights in Acacia catechu. Application of Phosphorus at 25 kg ha-1 resulted in maximum root dry weight in Acacia Arabica and Acacia catechu. Phosphorus application up to 25 kg ha-1 resulted in maximum number of nodules per plant in Acacia Arabica and acacia catechu. Highest nodules dry weight per plant was recorded with phosphorus application up to 25 kg ha-1 in Acacia catechu and Paraserianthes falcataria. Nitrogen application upto 20 kg ha -1 resulted in an increase in plant nitrogen content and reduction thereafter. Phosphorus application upto 25 kg ha -1. Resulted in an increase nitrogen content of plants and a reduction was noticed beyond 25 kg ha-1. Nitrogen application had significant influence on phosphorus content of plants in A Arabica and P. falcataria. Phosphorus application at 50 kg ha-1 gave highest phosphorus content in A. Arabica and A. catechu. It can be concluded that nitrogen and phosphorus application along with Rhizobium inoculation using specific strains is essential for better growth and nodulation of leguminous tree species.
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    ThesisItemOpen Access
    Sulpher and boron nutrition of groundnut (arachis hypogaea L)var TG-3
    (Department of Agronomy, College of Agriculture, Vellayani, 1992) Chandini, A; KAU; Chandini, S
    An investigation was undertaken at the college of Agriculture, Vellayani during the period from April to November 1990, to study the effect of different levels and time of application of sulphur (15 kg, 20 kg and 25 kg S.ha-1) and boron (4 kg and 6 kg B.ha-1) for groundnut cv. TG-3 in the red sandy clay loam of Kerala The investigation compared of an initial pot culture study followed by a field experiment. The pot culture study was laid out in completely randamised design and the field experiment in randomised block design with three replications. The highest dose of sulphur, viz. 25 kg S.ha-1 recorded significant influences on growth characters like plant height, number of leaves and leaf area index of the crop. The effect of boron was significant at 90 DAS for number of branches, at 90 DAS and at harvest for number of leaves, and at 60 DAS and 90 DAS for leaf area index. Significant response was noted only upto 4 kg B. ha-1 for growth characters. The effect of sulphur and boron application on nodule number was significant. But the three levels of sulphur and two levels of boron were on par with each other. Sulphur had a favourable influence on all the yield attributing characters viz. number of pods plant-1 , weight of pods plant-1, weight of kernels plant-1weight of pods plant-1, weight of kernels plant-1, 100 kernel weight and shelling percentage and consequently on pod yield, total drymatter production and harvest index. Sulphur at 20 kg and 25 kg S. ha-1 were found to be on par in their effects. Boron at 4 kg and 6 kg B. ha-1 were on par in influencing the pod number plant-1, pod weight plant-1, pod yield and bhusa yield of groundnut. There was a significant interaction between 25 kg S. ha-1 and 6 kg B. ha-1 for pod number plant-1. The oil content of groundnut kernels increased with progressive levels of sulpur and boron application. Sulphur at 20 kg and 25 kg and boron at 4 kg and 6 kg were on par in their effects. The protein content of groundnut kernels also increased with progressive levels of sulphur, with the levels 20 kg S. and 25 kg S. ha-1 on par with each other. But the protein content increased upto 4 kg B.ha-1 only. Sulphur and boron application enhanced the boron content of kernels significantly while application of sulphur alone increased the sulphur content of kernels. Maximum N, P and S uptake were noted when sulphur was applied @ 25 kg ha-1 . Maximum N uptake by the crop was noted when boron was applied @ 4 kg B. ha-1. B uptake was also significant only upto 4 kg B. ha-1. The time of application did not have any significant influence on growth characters, yield attributes, or yield of the crop.
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    ThesisItemOpen Access
    Effect of oxyflourfen for weed control in dry-sown rice
    (Department of Agronomy, College of Horticulture, Vellanikkara, 1992) Priya, I; KAU; Tajudeen, E
    A field experiment was conducted at Regional Agricultural Research Station, Pattambi of Kerala Agricultural University during the first crop seasons of 1991 and 1992 to find out the time and dose of application of oxyflourfen in dry-sown rice. The treatments included different doses of oxyflourfen (0.05, 0.10, 0.15 and 0.2 kg a.i./ha) on the same day of sowing, at 3 and 6 DAS, butachlor and Thiobencarb (1.5 kg a.i./ha) on the same day of sowing and two controls (weedy check and hand weeded check) laid out in randomised block design with three replications. The results showed that the count, dry matter production and nutrient removal of weeds were appreciably reduced by the weed control treatments particularly by oxyflourfen application @ 0.15 kg a.i./ha on the same day of sowing during initial stages and oxyflourfen application @ 0.2 kg a.i./ha at 3 DAS during later stages. The weed control efficiency was highest during critical stages in oxyflourfen applied plots @ 0.15 kg a.i./ha on the same day of sowing and was even higher than that of hand weeding and the effect was on par with oxyflourfen application @ 0.2 kg a.i./ha at 3 DAS. Oxyflourfen application @ 0.2 kg a.i./ha at 3 DAS gave significantly higher values of yield attributes viz. productive tillers, panicle length and number of filled grains per panicle resulting in higher grain yield and the effect was on par with hand weeding. These treatment showed highest straw yield also. The weed index values were lower in plots where, oxyflourfen @ 0.2 kg a.i./ha at 3 DAS were applied. In terms of returns per rupee invested also, plots treated with oxyflourfen @ 0.2 kg a.i./ha at 3 DAS was the best. Among the different levels of oxyflourfen, a dose of 0.2 kg a.i./ha at 3 DAS can be advocated for better weed control efficiency, higher yield and net return.
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    ThesisItemOpen Access
    Release of nitrogen and potassium from root contact packets of urea and muriate of potash and their crop responses
    (Department of Agronomy, College of Horticulture, Vellanikkara, 1992) Jomol, P Mathew; KAU; Vikraman Nair, R
    The present study 'release of nitrogen and potassium from root contact packets of urea and muriate of potash and their crop responses was conducted during June 1991 to June 1992 at the College of Horticulture, Vellanikkara. Root contact packets of varying porosities and quantities were prepared and separate experiments were conducted to study the efficiency of packets of urea and muriate of potash. A series of experiments were conducted to standardise the porosities suited to provide extended potention of the fertiliser packed in polythene packets. In studies conducted in north-east monsoon season, substantial retention of muriate of potash could be observed with porosities of one and two nuil holes cm-2 upto 90 days of application . The quantity retained was found to decrease significantly with increase in porosity.
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    ThesisItemOpen Access
    Molecular absorption of urea by flooded rice
    (Department of Agronomy, College of Horticulture, Vellanikkara, 1992) Safeena, A N; KAU; Balachandran, P V
    An investigation on molecular absorption of urea by flooded rice was conducted at the Radio Tracer Laboratory , College of Horticulture, Vellanikkara, during the period 1990-1992. The effect of soil submergence on soil urease activity was also studied on five different soils of Kerala namely, laterite, kole, kari, kayal and black soils. An attempt was also made to develop an isotope method for urease estimation using 14c labelled urea . From the specific activity of 14c urea solution initially added and the count rates obtained for the KCI-PMA extract, the urea hydrolysis rate was calculated.
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    ThesisItemOpen Access
    Growth and yield of cashew in relation to foliar and soil nutrient levels
    (Department of Agronomy, College of Horticulture, Vellanikkara, 1992) Latha, A; KAU; John, P S
    An experiment on the growth and yield of cashew in relation to foliar and soil nutrient levels was conducted during 1990-'92 by making use of seedling progenies of BLA-39-4 with three levels each of N (250, 500 and 1000 g /tree /year), P (125, 250 and 500 g P205 /tree /year) and K (250, 500 and 1000 g K2O /tree /year) and one absolute control (with out NPK application ). Significant response in increasing height and number of flushes was observed only for N (500 g /tree /year) and P (250 g P205 /tree / year). Leaf N and K content at flushing , flowering and fruiting were enhanced by application on of a ll the three nutrients with maximum values at flowering . Leaf P content was enhanced by N, P and K application only at flushing and fruiting . N, P and K application also increased the chlorophyll ‘ b 1 and total chlorophyll. There was increase In N and P content of soil by N, P and K application , while K content of s oil was increased only with higher levels of K. 2 The number of panicles/m and test weight of nuts and yield were increased by the application of N, P and K. A positive significant relationship was obtained between leaf N and P contents at flowering and fruiting stages and yield . There was progressive increase in nut volume , protein content of kernels and fruit characters such as fruit weight, fruit volume and TSS of apple by N, P and K application .
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    ThesisItemOpen Access
    Evaluation of shade tolerant morphotypes of colocasia
    (Department of Agronomy, College of Horticulture, Vellanikkara, 1992) Hemalatha, S; KAU; Tajuddin, E
    The present study 'Evaluationo f shade tolerant morphotypes of colocasia' was conducted during May to December 1990 at the College of Horticulture and Instructional Farm, Vellanikkara, Thrissur, Kerala, India. Experiment at College of Horticulture was laid out in split plot design with four shade levels in the main plot and six morphotypes in the sub plot. The experiment was carried out with four replications providing 0, 25, 50 and 75 per cent shade. For providing shade, pandals were erected on wooden frames and covered with unplaited coconut fronds on all sides leaving a clearance of 1 m from the ground level. Shade intensities were adjusted using Line quantum and Point quantum sensors. Experiment at Instructional Farm, Vellanikkara was laid out in randomised block design with four replications. Six morphotypes of colocasia raised under artificial conditions at College of Horticulture, were raised in the interspaces of coconut garden; at the Instructional Farm. Under artificial conditions, most of the colocasia morphotypes recorded the highest yield at 25 per cent shade and hence this crop is classed as shade loving corp. Though shading had no significant effect on corm yield, cormel yield and harvest index, there was variation in all these parameters among the morphotypes and M recorded the highest value. Morphotypes M„, M,_ and M were ' 2 10 16 selected as better yielders for all shade situations. Starch content of tubers increased with shading whereas oxalic acid content remains unaffected. Most of the morphotypes evaluated performed similarly under artificial as well as natural shade. Eleven light infiltration observations from different locations were taken at hourly intervals from 9 am to 5 pm, using Line quantum and point quantum sensors and percentage values were worked out. Mean percentage light infiltration values obtained revealed that there is no consistent relationship between light infiltration and height of the coconut palms or spacing.
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    ThesisItemOpen Access
    Evaluation of turmeric cultivars for shade tolerance
    (Department of Agronomy, College of Horticulture, Vellanikkara, 1992) Sheela Paul; KAU; Sreedevi, P
    An experiment, 'Evaluation of turmeric cultivars for shade tolerance' was conducted during May 1990 to February 1991 at the College of Horticulture, Vellanikkara, Thrissur, Kerala, India. Two separate trials were carried out one under artificial shade and the other under natural shade in coconut garden. The trial under artificial shade was to assess the performance of turmeric cultivars under different shade levels, whereas that under natural shade was to test the fitness of these cultivars as intercrops in coconut garden. Trial under artificial shade was laid out in split plot design with four shade levels, 0, 25, 50 and 75 per cent in the main plots and six cultivars PCT-5, BSR-1, Ethamukulam, PTS-9, PCT-8 and PTS-38 in the subplots. For providing shade, pandals were erected on wooden frames and covered with unplaited coconut fronds to provide desired levels of shade. LI-COR integrating quantum radiometer with line quantum sensor was used for adjusting the shade intensities. Though no . significant difference was observed between cultivars at different shade levels, all cultivars gave highest rhizome yield at 50 per cent shade. Hence turmeric may be calssified as a shade tolerant/shade loving crop. Yield parameters such as drymatter production and harvest index were also more at 50 and 75 per cent shade, respectively. Among the cultivars P C T -8 , the highest yielder gave higher values for drymatter production, harvest index, chlorophyll content and percentage dryage. On analysing the performance of different cultivars at varying shade intensities; all the cultivars i were found to be better at 50 per cent shade, above which there was a declining trend in yield. The treatment differences were, however, not significant. In general, PCT-8 and PTS-9 performed better both under shade and in the open. Though different prediction models were tried, no model was found to be a good fit for the cultivars. Under natural shade, similar performance was exhibited by all the five cultivars tested with respect to rhizome yield, growth and yield attributes. However, BSR-1 outyielded the other cultivars. The same cultivar recorded more, content of chlorophyll, curcumin and oleoresin. In general, the performance of all the cultivars was poor under intercropping in coconut garden