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  • ThesisItemOpen 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 S
    A 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.
  • ThesisItemOpen Access
    Standardisation of fertilizer schedule for export oriented production of bhindi
    (Department of Agronomy, College of Agriculture, Vellayani, 1993) Sajitharani, T; KAU; Pushpakumari, R
    An 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).
  • ThesisItemOpen Access
    Irrigation scheduling and moisture conservation in water melon
    (Department of Agronomy, College of Horticulture, Vellanikkara, 2000) Ajith, C B; KAU; Joseph, P A
    An experiment was conducted at the Agricultural Research Station, Mannuthy, Thrissur during the period from December 1998 to March 1999 to study the influence of levels of irrigation and moisture conservation methods on the growth and yield of water melon (Citrullus fanatus) grown in rice fallows. The experiment was laid out in randomized block design with three replications. The treatments consisted of combinations of four moisture conservation methods (control, application of paddy waste as surface mulch, uniform incorporation and bottom layer application @ 1/3 pit volume) and four levels of irrigation (IW /CPE ratio of 0.6, 1, 1.4 and farmer's practice of daily irrigation @ 20 lit pit"), The study revealed that incorporation of moisture conservation materials increased the growth attributes like length of vine, number of leaves per vine, leaf area and dry matter production and yield attributes like weight of fruits and number of fruits per plant. Among moisture conservation methods surface mulch and uniform incorporation of paddy waste were found to be superior in most of the cases. Watermelon responded very well to irrigation. Biometric characters (length of vine, number of leaves per vine, leaf area and dry matter production) and yield attributing characters (weight of fruits and number of fruits per plant) were favourably influenced by frequent irrigations. The fruit yield increased with increase in frequency of irrigation and was maximum at IW /CPE ratio of 1.4. Results of soil moisture studies revealed that incorporation of moisture conservation material' increased the soil moisture content, consumptive use and water use efficiency. 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. Field and crop-water use efficiencies were higher in less frequently irrigated treatments. Higher levels of irrigation increased N, P and K content of leaves. No convincing change in leaf N, P, K content could be brought about by the incorporation of paddy waste. Economic analysis showed that incorporation of paddy waste could increase the net profit. Net profit as well as net return per rupee invested were the highest with scheduling irrigation at IW/CPE ratio of 1.4. Among the treatment combinations, the best combination was surface application of paddy waste with irrigation at IW/CPE ratio of 1.4 followed by the combination of surface mulching and fanner's practice of daily irrigation.
  • ThesisItemOpen Access
    Investigation on allelopathic influence and control of purple nuts edge
    (Department of Agronomy, College of Agriculture, Vellayani, 1999) Ameena, M; KAU; Sansamma, George
    Lab and field experiments were conducted at the Instructional farm, College of Agriculture, Vellayani to study the allelopathic influence of Purple nutsedge (Cyperus rotund us L) on important field crops; to investigate the effectiveness of systemic herbicides for control of nutsedge and also to assess the effect of chemical weed control on growth and yield of subsequent field crops. In Ex. no. I, allelopathic influence of purple nutsedge on important field crops like rice, ragi, cowpea, green gram, bitter gourd and bhindi were studied. The treatments comprised of aqueous extracts and blended extracts of fresh and dry plant parts of nutsedge. The results revealed that aqueous extracts of nutsedge inhibited germination of rice, ragi, bitter gourd and bhindi while it had some stimulatory effect on germination of cowpea and green gram. The early growth characters of the field crops were found suppressed by the aqueous extract treatment while the blended extract showed no effect. In general, the dry plant parts showed greater effect than the fresh material. Under Ex.no.Il, field studies were made to investigate the effectiveness of systemic herbicides viz. Glyphosate and 2,4-D for control of nutsedge. The treatments included different doses of the herbicides with and without adjuvants and Glyphosate combined with sublethal dose of 2,4-D. The results revealed that lowest dose of the herbicides were sufficient for complete kill of the purple nutsedge plants in the experimental area and there was no regrowth upto 6 weeks. There was significant reduction in viability of tubers collected one month after herbicide application, but the tubers tested 45 days after spraying showed an increase in germinability over the record on 30th day. Tubers from treatments involving Glyphosate with sublethal dose of 2,4-D recorded the lowest sprouting percentage indicating the possibility for weed control for a longer period. In Ex. no. In, the persistence of the herbicides in soil were monitored and it was observed that early growth of cucumber sown on the same day of herbicide application was affected while that sown on soils collected 10 days after spraying recorded growth characters comparable to that of control. From Ex.no.IV, it could be inferred that chemical weed control did not show any deleterious effect on growth and yield characteristics of ragi and cucumber sown 15 days after the treatments. Application of 2,4-D for nutsedge control was found superior to other treatments in terms of net income and B:C ratio and the lower unit cost of the chemical was precisely the reason for its superiority.
  • 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.
  • ThesisItemOpen Access
    Root Distribution patterns of Banana and Colocasia in Coconut Gardens
    (Department of Agronomy, College of Horticulture, Vellanikkara, 1994) Suja Eapen, KAU; Abdul Salam, M
    An investigation was undertaken at the College of Horticulture, Vellanikkara during 1993-94 to study the root disribution patterns of banana and colocassia in coconut gardens. The experiments were aimed to study the root distribution patterns of banana var. Palayankodan growth in the open and in the coconut garden under rainfed and irrigated conditions. It was also aimed to study the variation in the root distribution patterns of colocasia var. Cheuchempu grown in the coconut garden and in the open. A 32p plant injection technique and a direct profile excavation technique were employed to study the root distribution patterns. The salient results of the investigation are abstracted below. BANANA Root production of banana grown in the open was considerably more compared to that grown in coconut garden. Rainfed banana produced more roots compared to irrigated banana. The root distribution patterns of banana vary with growing condition. In the coconut garden, the root system of rainfed banana was spreading and that of irrigated banana was compact. When grown in the open condition, the root system of rainfed banana was compact and that of irrigated banana was spreading. The active root zones of rainfed banana grown in the open, irrigated banana grown in the open, rainfed banana grown in the coconut garden and irrigated banana grown in the coconut garden were the root zones comprising L0-60 D0-60, L0-60 D0-80, L0-80 D0-60 and L0-60 D0-60 respectively. COLOCASIA Root production of colocasia was more with the plants grown in the open compared to that grown in the coconut garden. Root distribution patterns of colocasia differ between the plants grown in the coconut garden and in the open. The root system of colocasia grown in the coconut garden is deep compact and that of the plants grown in the open is deep spreading. The active root zone of colocasia in the open and in the coconut garden are the root zones comprising L0-20 D0-40 and L0-10 D0-40 respectively. 32P plant injection technique is an efficient method for root system studies in both banana and colocasia.
  • ThesisItemOpen Access
    Resmi S
    (Department of Agronomy, College of Agriculture, Vellayani, 1993) Muraleedharan V
    With a view to assess the role of Azospirillum on growth and productivity of rice as ameans of economising fertilizer nitrogen application, a field experiment was conducted at the Instructional Farm, College of Agriculture, Vellayani during the period from June 1992 to September 1992. The variety used as Red Triveni. The experiment was laid out as 4x3x2+1 factorial experiment in randomised block design with two replications. The treatments includes four methods of inoculation of Azospirillum (seed, seedling root dip, soil and combined inoculation), three levels of nitrogen (50, 75 and 100 per cent recommended dose of nitrogen) and two levels of lime (without and with lime) along with a control (KAU Package of Practices). An abstract of the results is given below. Among the different methods of Azospirillum inoculation, combined application influenced almost all the growth characters significantly. Application of 100 per cent recommended dose of nitrogen and lime application also influenced the growth characters significantly. Among the yield attributes, productive tillers per square metre, and panicle weight were significantly influenced by various treatments. The combined application of Azospirillum recorded the highest grain yield. Similarly 75 per cent recommended dose of nitrogen and liming also recorded higher grain yields. A significant change in harvest index was also observed due to various treatments. Uptake of nutrients was significantly influenced by all the treatments. Among the inoculation methods, combined method of inoculation recorded the maximum uptake. Similarly highest level of nitrogen and lime application showed the highest uptake of nutrients. Combined method of inoculation, highest level of nitrogen and lime application recorded the highest value of protein content. Economic analysis of data revealed that combined application of Azospirillum plus 75 per cent nitrogen plus lime produced a net income which is comparable with the highest net income produced by combined application of Azospirillum plus 100 per cent nitrogen plus lime. When compared to control the net income produced by these treatments are higher, indicating the superiority of the above treatments. Thus it is seen that we can save atleast 25 per cent of the fertilizer nitrogen by incorporating the Azospirillum through combined application.
  • ThesisItemOpen 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 L
    A 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.
  • ThesisItemOpen Access
    Development of subsurface pad irrigation system for tomato
    (Department of Agronomy, College of Agriculture, Vellayani, 1995) Abdul Nassar, K; KAU; Jaikumaran, U
    An 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.