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Anand Agricultural University, Anand
Anand Agricultural University (AAU) was established in 2004 at Anand with the support of the Government of Gujarat, Act No.(Guj 5 of 2004) dated April 29, 2004. Caved out of the erstwhile Gujarat Agricultural University (GAU), the dream institution of Sardar Vallabhbhai Patel and Dr. K. M. Munshi, the AAU was set up to provide support to the farming community in three facets namely education, research and extension activities in Agriculture, Horticulture Engineering, product Processing and Home Science. At present there seven Colleges, seventeen Research Centers and six Extension Education Institute working in nine districts of Gujarat namely Ahmedabad, Anand, Dahod, Kheda, Panchmahal, Vadodara, Mahisagar, Botad and Chhotaudepur
AAU's activities have expanded to span newer commodity sectors such as soil health card, bio-diesel, medicinal plants apart from the mandatory ones like rice, maize, tobacco, vegetable crops, fruit crops, forage crops, animal breeding, nutrition and dairy products etc. the core of AAU's operating philosophy however, continues to create the partnership between the rural people and committed academic as the basic for sustainable rural development. In pursuing its various programmes AAU's overall mission is to promote sustainable growth and economic independence in rural society. AAU aims to do this through education, research and extension education. Thus, AAU works towards the empowerment of the farmers.
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ThesisItem Unknown SOIL AND NUTRIENT LOSSES THROUGH RUNOFF FROM LOAMY SAND SOILS UNDER DIFFERENT CROPPING SYSTEMS(AAU, Anand, 1994) Sutaria, Gangdas Samjibhai; Patel, N. K.The field experiments were conducted at the College Agronomy Farm, Gujarat Agricultural University, Anand Campus, Anand, to study the soil and nutrient losses through runoff from loamy sand soils (Ustifluvents) under different cropping systems during Kharif season of the year 1992 and 1993. There were ten treatments consisted of sole crop of pearlmillet, pigeonpea, bidi-tobacco and groundnut and their intercropping systems including cultivated and absolute fallow treatments. The results revealed that both the runoff (152.0 mm) and soil loss (8469 kg ha-1 ) were maximum under cultivated plot. Per cent runoff loss under sole crops of groundnut, pearlmillet, pigeonpea and bidi-tobacco was to the tune of 13.9, 16.7, 27.4 and 30.9 per cent of the total rainfall, respectively. The corresponding values for soil loss was 2015, 2516, 6141 and 7436 kg ha"^ for these crops. Runoff loss from bidi-tobacco and pigeonpea was reduced to the extent of 34.0 and 32.7 per cent and that of soil loss by 45.3 and 42.5 per cent when groundnut crop intercropped with these crops. The highest content of various nutrients (N, P, K) in runoff water and that in sediment fractions were observed under sole groundnut crop. The contents of these nutrients in runoff water and in sediment fractions were enhanced under intercropping of groundnut with bidi-tobacco and pigeonpea as compared to that in sole crops. The total loss of nutrients through erosion under sole crops of biditobacco and pigeonpea was 120.2 and 101.2 kg ha-1 , respectively. These loss of nutrients curtailed to the extent of 37.8 and 32.3 per cent when groundnut crop was introduced as intercrop with these crops. The sediment was the main source of loss of nutrients through erosion. Significant negative relations were observed between runoff and soil losses with nutrients enrichment ratios in sediment fractions. The enrichment ratios for various nutrients was high with sole groundnut and it was low with bidi-tobacco and pigeonpea. The fractions of silt and clay were more in eroded sediment (14.05 to 26.94 %) than the soil from which they derived (11.0 %) . The cultivated fallow plot retained more soil-water during dry spell than cropped plots. In contrast to this, cropped plots stored more water than cultivated fallow plot during rainy season. Groundnut as sole or intercrop improved the soil fertility and physical conditions of the soil. The EI30 is a good index for the prediction of runoff and soil losses. Average annual rainfall erosion index (R) is arrived as the figure 772.59. The July and August months contributing 72.39 per cent of EI30 and these months are the most erosive months. Prediction models are developed for measurement of KE and EI30 based on daily rainfall data. Sole pearlmillet and groundnut as well as groundnut intercropped with bidi-tobacco and pigeonpea crops have low crop management factor (C). Soil erodibility factor (K) is worked out to be 73.0 kg ha-1 per unit of erosion index. Prediction models were also developed using multiple factors of USLE (erosivity, crop management and soil erodibility factors) for calculation of runoff and soil losses. The impact of different cropping systems on yield, monetary returns and uptake of nutrients were also studied. The results indicated that pearlmillet crop benefitted from intercrop while pigeonpea and bidi-tobacco crops affected adversely by intercrop. The productivity per unit area was increased by 23 per cent when groundnut intercropped with pigeonpea and bidi-tobacco crops. Incorporation of groundnut as intercrop with bidi-tobacco and pigeonpea crops gave extra monetary returns of 896 and 2648 Rs . ha-1, respectively than that from corresponding sole crops. The uptake of various plant nutrients were high under intercropping system in comparison to that in sole cropping system.ThesisItem Open Access ASSESSMENT OF IRRIGATION REQUIREMENT OF NARMADA COMMAND USING SOIL-CROP-CLIMATE DATA(AAU, Anand, 1997) GIRI, JAYANT DATTATRAYA; PATEL, G. R.The assessment of irrigation requirement of Narmada Command covering an area of 18 lakh hectares (1.8m ha) has been carried out using data on soil available water capacity and evapotranspiration data on crops viz., pearl millet, groundnut, pigeonpea, cotton, castor, mustard and wheat. The crop evapotranspiration (ETc) is computed using crop coefficient values (Kc). While ETc has been found to be mainly dependent on the climatic component, the Net Irrigation Requirement (NIR) has been found to depend on climate mainly effective rainfall and the soil available water capacity (AWC). Differences between the Crop Water Requirement (CWR) and NIR were wide for the monsoon season, but narrowed down considerably in the winter and summer seasons. The AWC and the length of growing period of crop have also contributed to the NIR values. Soils with higher AWC had lower NIR while crops with longer growing season showed higher NIR. The AWC of soils has been found to be mainly governed by the soil texture more so by the clay + silt or clay contents. In general, medium textured soils had higher AWC than either coarse or fine textured soils. The 60 per cent level of depletion of AWC has been used to initiate irrigation. The number of irrigations required and the quantity of water applied depends on the overall evaporative demand of climate, the length of growing season of the crop and the AWC of soils. Seasonal evaluation of the scheme water supply efficiency revealed that in general the values were below 1.0 and tended to be around 0.5. The values were around 0.5 during the months of high evaporative demand and considerably less during the monsoon and cooler months when the evaporative demand is lower. However, these values are expected to be higher once all the crops grown will be considered. Scheme efficiency (relation between supply required and actual supply) can be improved by growing perennial crops like sugarcane and banana and such other crops having a high requirement for water. Such crops are recommended to be grown on as soils with no root zone limitations or other limitations imposed by the physical and chemical properties of soils. During months of low water requirement use of exploitable ground water is also recommended. Such conjunctive use will help in saving water which otherwise will go as wasteful flow and also help to keep the ground water level well below problematic levels. Use of data on soil-crop-climate to achedule irrigations for the various crops revealed it to have substantially leas NIR values as compared to the IW/CPE ratio for monsoon season crops and compared well for the winter crops. In the summer, it predicted a less NIR than IW/CPE for groundnut but gave higher values than IW/CPE for pearl millet. The redeeming feature of the model is that it takes into consideration the effective rainfall (Total rainfall less that lost through run-off or deep percolation). The soil-crop-climate model compared well with the other methods of irrigation tried, for the yield of grain in all the crops studied. It gave less WUE than the critical stages approach for all the crops except wheat, where Ife gave higher WUE values. In case of pearl millet and mustard it gave less WUE than the IW/CPE ratio. This may be attributed to the fact that these crops have basically less requirement for water and hence, gave no significant response to any increase in water supplies beyond a certain level. Studies on the behaviour of the model as compared to the other schedules for the nutrient depletion pattern Indicate that no definite pattern with respect to nutrient uptake has emerged and the results had a fair measure of inconsistency. The inherent variability of the crops studied for their capacity of derive nutrition, the natural relationships among the nutrients and the inherent difference in the soil's capacity to supply nutrients can be attributed to the observed inconsistency. Since the model gives moderate dry matter production, it causes moderate depletion of nutrient and hence with proper management and monitoring of the soil fertility, it is expected to give sustained agricultural production. Study on evolving alternative irrigation management practices in areas suffering from problems of rising water table were carried out. Results revealed that for groundnut use of sprinkler system of irrigation with an application depth corresponding to 2.5 cm per irrigation at two stages of crop growth viz. pegging (55 DAS) and pod development (85 DAS) with two irrigation of 5 cm each as pre-sowing and pre-harvest proved to the most beneficial (5.7 t/ha kernel yield). Growing groundnuts without Irrigation (4.6 t/ha) except a pre-sowing irrigation was the next best alternative. Irrigating groundnut at pre-sowing, 55 DAS, 85 DAS and pre-harvest stages with 5 cm depth of application each time had serious negative effects on yield (2.6 t/ha). Under such situations use of sprinklers appears to be a promising alternative as besides giving higher yield it may also help in keeping the ground water level within manageable limits. Growing groundnut without irrigation appear to be the next best alternative. From the study conducted It can be concluded that the soil-crop-climate model, can be used as an effective tool for predicting regional estimates of irrigation requirement inspite of the wide diversity of climate, soil and crops grown In any region, because it takes into consideration these very variables. It is also easy to compute the requirement and has the added advantage of using minimum data sets. The data collected once can be applied without the need for recurrent data collection for a reasonably long time. However, before final conclusions can be drawn, the model needs to be validated for larger number of crops, wider variety of soils and different climatic situations. Because of its requirement of minimum data sets, however it appears to be an attractive alternative tool for making regional estimates of water requirement and merits scientific attention.ThesisItem Open Access EFFECT OF POOR QUALITY IRRIGATION WATER THROUGH DRIP SYSTEM ALONGWITH FARM YARD MANURE AND PLASTIC MULCH ON CHANGES IN VERTISOL AND PERFORMANCE OF TOMATO CROP(AAU, Anand, 1995) DESAI, RAMESHCHANDRA MAGANLAL; PATEL, J. C.A field experiment was conducted at Narmada Irrigation Research Project, Khandha (Karjan) on Vertisols (heavy black) to study the effect of poor quality irrigation water (EC 2.1 dSm-1 SAR 10.8 and Mg/Ca ratio 2.1) using flood and drip system with or without FYM and black plastic mulch (PM) on changes in properties of soil and performance of tomato crop during Rabi season of 1993-94. The effect of monsoon rain on changes in properties of soil was also studied. Ten treatment combinations viz., 50 mm flood (0.8 PE) and three levels of drip viz. D1(0.45), D2(0.60) and D3(0.75 PE) with or without FYM as well as black PM(50) at 0.45 PE with or without FYM were tried in randomised block design with four replications. The use of black polyethylene mulch alongwith drip irrigation at 0.45 PE showed maximum plant height, number of branches per plant and leaf area index. The use of drip irrigation was better with respect to above parameters over flood system. The levels of irrigation and application of FYM did not show significant response. The development of roots (dry weight, length and volume) was significantly higher under PM alongwith drip irrigation at 0.45 PE. Application of FYM was effective at higher level (0.75 PE) of drip irrigation only. The number of fruits per plant and mean weight of fruits were maximum under PM' treatments. The performance of drip system in respect of number of fruits per plant was better over flood. The fruit yields were significantly highest under PM treatment! during both the periods. The fruit yields under D1 + PM (75.29 Mg ha-1), D1 + PM + FYM, D3 + FYM and D3 treatments were 96.6, 67.8, 65.1 and 63.0 (period I), as well as 82.8, 62.5, 46.4 and 44.7 (overall) per cent higher, respectively over flood irrigation (41.19 Mg ha-1 ). The effect of application of FYM was not significant. The stalk yield was maximum under PM along with lower level of drip irrigation (0.45 PE) followed by treatment D3 (0.75 PE). The water use efficiency (kg ha-1 m-1 ) was maximum in D1 + PM (173.36) followed by D1 + PM + FYM (154.4) while increasing levels of drip irrigation reduced. the WUE irrespective of FYM application.ThesisItem Unknown PHYSICO-CHEMICAL AND SMOKE CHARACTERISTICS OF BIDl TOBACCO AS INFLUENCED BY NITROGEN, TOPPING AND SUCKERICIDE(AAU, Anand, 1996) Patel, A. M.; Patel, B. K.An experiment was conducted under middle Gujarat agro-climatic conditions at the Bidi Tobacco Research Station, Anand, during 1993-94 and 1994-95 with a view to knowing the differences in the physico-chemical and smoke characteristics of bidi tobacco (cv A 119) as affected by nitrogen, topping and suckericide. The experiment comprised combinations of three levels of nitrogen (200 (Ni), 300 (N2 ) and 400 (N3) kg ha-1 Mand two topping stages (topping at button stage (Ti) and at bald sucker stage (T2) alongwith three concentrations of suckericide (0.60 (Si), 0.75 (S2) and 0.90 (S3) per cent pendimethalin) alongwith hand desuckering (So) as a control. The experiment was laid out in a split plot design with four replications, wherein nitrogen levels were embedded in the main plot, while combinations of topping stages and suckericide levels were assigned to the sub plots. The nitrogen application showed significant progressive improvement in the growth attributes viz., leaf length, width, area, LAI, RGR-I and plant height with the concomitant increase in the levels of applied nitrogen from 200 to 400 kg N ha-1 . But the increase in dry weight per unit area was observed upto N2, which in turn had significantly increased yield at N2 over N1, The difference between N2 and N3 was not significant, but lower yield was noticed at Na possibly due to significantly higher weight of suckers under Na than N2 and N1 treatments. The spangle score was the highest under N3 , however,N1 and N2 did. not differ significantly. The produce from N2 treatment fetched the highest price (Rs. 16.0 kg-1), net realization (Rs. 51050/- ha-M and gave maximum CBR (1:3.82) followed by N1 and N3 levels of nitrogen. The chemical quality parameters viz., nitrogenous constituents, total and non volatile carbonyls, volatile acids, and hexane extractives were in favour of N2, while reducing sugar and chloride contents were the highest under Ni. The inorganic constituents viz., total ash, P, K, Ca and Mg were also maximum under N2 treatment. In case of smoke constituents also N2 recorded the highest values for NFDPM, smoke nicotine, smoke phenols with intermediate number of puffs bidi-1.ThesisItem Open Access PERSISTENCE OF PENDIMETHALIN, FLUCHLORALIN AND OXADIAZON IN SOIL AND THEIR RESIDUES IN ONION (Allluin cepa L. )(AAU, Anand, 1997) Raj, Mahendrasinh Fulabhai; Patel, B. K.Pendimethalin, fluchloralin and oxadiazon were applied @ 1.0, 1.0 and 0.5 kg ha-1, respectively as preemergence herbicides in an experiment conducted at College Agronomy Farm on onion in rabi 1995 to study their persistence in sandy loam soil and residues in onion. Adsorption-desorption of the herbicides and their downward movement in the soil columns were also carried out in the laboratory to work out the risk of groundwater pollution. The herbicides were mainly retained within 0-15 cm soil layer. Pendimethalin, fluchloralin and oxadiazon showed first-order dissipation with half-life values of 21.9, 19.1 and 32.4 days, respectively. FYM application(0, 10 and 20 t ha-1) reduced the degradation of all the herbicides. The dinitroaniline herbicides showed biphasic mode of dissipation, whereas it was monophasic in case of oxadiazon. The herbicides did not show marked effect on the soil microbial biomass carbon as well as nitrate nitrogen. The levels of pendimethalin, fluchloralin and oxadiazon residues in onion ranged from 0.003 to 0,021, 0.004 to 0.036 and 0.080 to 0.104 µg g-1, respectively. The residues in onion were marginally higher on the 60th day than at harvest. Adsorption-desorption of pendimethalin, fluchloralin and oxadiazon was studied on sandy loam and clayey soils. Pendimethalin showed maximum adsorption on both the soils, however, oxadiazon was the least adsorbed. Organic matter content of the soil was predominantly responsible for adsorption of the herbicides which was evident by low Koc values of the herbicides for clayey soil. In sandy loam soil, fluchloralin recorded maximum desorption followed by oxadiazon and pendimethalin. Soil column study carried out for one month period revealed little movement of pendimethalin and fluchloralin beyond 12 cm depth, however, oxadiazon reached upto 30 cm soil depth. With increase in soil depth, the soil microbial biomass carbon increased in case of fluchloralin and oxadiazon, while, the increase was marginal for pendimethalin. Among the three herbicides, oxadiazon showed better negative correlation(r=-0.81) between the residues and biomass carbon. None of the herbicides were detected in the leachates.ThesisItem Unknown BIOGAS FERMENTATION AND PHASE SEPARATION STUDIES OF SOME PLANT MATERIALS(AAU, Anand, 1992) Marsonia, P. J.; Goswami, K. P.Fermentation studies on four vegetative materials (ipomea leaves, water hyacinth, neem leaves and rice straw) were carried out in duplicate.sets with 5 g substrate, 10 ml active inoculum and 6,67 per cent solids in 250 ml flask as digester. Each digester was swirled daily while, the gas was collected by displacement of acidulated water in calibrated bottles; all the assemblies were housed in incubator maintained at 37°C or at room temperature. For biphasic studies, acidogenlc and methanogenic phases were physically separated at 37°C where VFA or biogas were estimated separately. There was no significant difference in gas production from rice straw cut to different size in a single phasic batch study. The highest biogas yield was 445.2 ml/g from rice straw treated with 10 % CaCO3 at 37°C. Ipomea and neem leaves gave the highest gas production 260 ml, and 332.2 ml/g dry matter at room temperature when respectively treated with 2 % N + 10 % CaC03 and 2 % N + 20 % CaCO3. Application of 1.44 % nitrogen to rice straw gave significantly higher biogas yield (394 ml/g straw) over rest of the treatments at room temperature. Similarly, application of cobalt (8 ppm), boron (6 ppm) and iron (200 ppm) stimulated biogas production from rice straw at 37°C and 15°C temperature. Higher biogas yields (40 % and 58 %) were recorded in 3:2 cowdung: 3-day presoaked green ipomea mix and 2:3 cowdung : 7-day presoaked green ipomea mix as compared with that from cowdung alone. The VPA yields in I-phase (batch) of two-phase system, were 7.38, 7.80, 5.66 and 3.02 g/1 as acetic acid from dried ipomea leaves, water hyacinth, neem leaves and rice straw in 3, 3, 2 and 5 days retention times. A slightly higher VFA production was observed from green plant materials. Recharging with water, after filtration and removal of plant acids has resulted in additional significant recovery of VFA. The biogas yields were 433, 429, 395 and 254 ml/g dried material in the Il-phase of this study respectively from dried ipomea, water hyacinth, neem leaves and rice straw after 10 days retention time with > 62 % methane. Similarly 436, 586 and 377 ml biogas/g dry weight were observed from the VPA of green ipomea, water hyacinth and neem leaves, respectively. In the I-phase of semicontinuous biphasic study, higher VPA production (7.8, 8.2, 7.6 and 4.9 g/1) were achieved from dried ipomea, water hyacinth, neem leaves and rice straw in 4, 4, 3 and 6 days retention time, respectively. In the second phase digestion of this study, the biogas yields were 1.44/ 1.18, 1.28 and 0.73 1/1 of digester during 6, 4, 4 and 3 day retention time from the VFA of dried ipomea leaves, neem leaves, water hyacinth and rice straw, respectively. Generally a higher level of biogas production was maintained in the " two-days" refeeding schedule in the methanogenic phase of batch fed system. Optimum VFA was produced from rice straw established at C/N = 13.8. Optimal VFA/1 volume was recorded with 6.67 % solids during the fermentation of rice straw and green ipomea leaves. Higher dry matter gave higher VFA when expressed on substrate basis. Highest amount of VFA was harvested when tice straw was buffered at pH 6.5 and green ipomea at pH 7.0. Higher lignin content gave lower amount of VFA from rice straw of different lignin content.ThesisItem Open Access TRANSFORMATION AND TRANSPORT OF NITROGEN CARRIERS AS AFFECTED BY DEPTHS OF WATER AND GROWTH OF TOBACCO(AAU, Anand, 1992) Babariya, Nandlal Bhimabhai; Patel, C. L.The effect of infiltration of 5, 10 and 15 cm water on transformation and transport of surface applied ammonium sulphate (AS), Urea, Calcium ammonium nitrate (CAN) and nitrophosphate (NP), at one, 10 and 20 days after irrigation was stuidied in soil column. Field lysimeter experiment with loamy sand soil was undertaken to evaluate the effect of same N-carriers on yield and chemical composition of bidi tobacco (GT 5) (Nicotiana tabacum L.) and transformation and transport of N-carriers at various depths of soil during the growth period of 45, 90, 135 and 150 days after transplanting. Effect of transparent plastic mulch on evapotranspiration, yield, chemical composition and N-dynamics in lysimeter soil profile was also studied. Transformation of N-carriers into NO3 form ranged from 24.9 to 41.7 mg kg-1 during incubation period of 1 to 20 days, concomitantly NH4+ - N content decreased from 16.20 to 0.0 mg kg-1. The NH4- and NO3- N content declined with rise in depths of water application from 5 to 10 cm. The rate of nitrification was rapid in case of urea followed by AS, NP and CAN, The penetration of wetting front after 24 hours was found at 21, 42 and 63 cm depth coinciding NOl accximulation with the respective application of 5, 10 and 15 cm water. The migration of water alongwith NO3- was more deeper (6 or 7 cm) during 10 to 20 days period than that of one day. The NH4+ - N content depressed while NO3- - N content elevated with depth under water application rates after 24 hours but such trend was not maintained beyond this period. Urea showed significantly high NH4+ - and NO3- - N content in soil dxiring 45 days growth of tobacco and at subsequent stages of growth all sources were at par with respect to NO3- - N content. The highest NO3- - N content (23.53 mg kg-1 ) was confined to 0-30 cm depth of soil and reduced significantly with depth during growth of the crop. The NO3- - N accumulation in soil varied from 21.76 to 13.84 mg kg-1 during 45 to 90 days after transplanting, respectively. The CAN gave 36 per cent higher cured leaf yield than that of NP (96.00 g/plant)• The NO3- - and NH4+- N contents in leaf lamina were highest with CAN and AS, respectively. The per cent N losses through volatilization/ denitrification were highest with urea followed by NP, CAN and AS. Under lysimeter condition, the unaccounted for N was in order of Urea > AS > NP > CAN. Use of plastic mulch saved 10 cm water besides increasing nitrogen use efficiency by minimizing N-losses.ThesisItem Open Access PERSISTENCE OF FLUCHLORALIN AS AFFECTED BY SELECTED SOIL PROPERTIES AS WELL AS AGRONOMIC PRACTICES AND ITS RESIDUES IN CHICORY ( Cichorium intybus, L. )(AAU, Anand, 1995) PATEL, R. B.; PATEL, B. K.Persistence of fluchloralin was studied in the field and laboratory with varying soil conditions, crops and methods of application. Field experiments with chicory crop were conducted to study the dissipation of fluchloralin in loamy and sandy loam soils. The results revealed that the fluchloralin persisted little longer in the loamy soil of Mehlav than the sandy loam soil of Qamdi probably due to the higher organic carbon status of the latter. Also it was observed that the residues were largely confined to the upper soil layer (0 7.5 cm) and movement to the lower depth was negligible. This was evident by the laboratory study carried out with PVC columns. The dissipation of fluchloralin followed first order kinetics and showed biphasic pattern in soils under chicory crop, while in micro plot, monophasic pattern was observed. The overall half-life values ranged from 42.39 to 45.60 days in chicory cropped soil, while in combination with FYM, it was 24.08 to 25.95 days and 23.15 to 23.70 days for 1.5 and 3.0 kg ha"^ application, respectively, in loamy soil. The half-life values were higher in loamy soil than the sandy loam soil. After 150 days, 5 to 7 per cent of the applied fluchloralin persisted in the soil. Fluchloralin was detected in chicory roots and leaves at the 60th day, but at harvest the residues were not detected. In a micro plot experiment, fluchloralin residues were decreased with increasing levels of FYM. When fluchloralin and FYM were applied together, no significant change was noticed in the persistence of fluchlorajin, N03"N and organic carbon content. However, microbial population in the soil was significantly affected immediately after their application. In a laboratory study with PVC column it was observed that fluchloralin did not move beyond 15 cm soil depth. The major metabolite, 2,6-dinitro-N-n-propyl- a,a,atrifluoro- p-toluidine, of fluchloralin was found in clayey soil under moist conditions. With respect to different methods of application, the residues were higher in pre-plant incorporation method than pre-emergence method. This indicated that the PPI method is more effective for controlling weeds. The toxic level of fluchloralin for mustard seedlings was found to be 0.38 µg g-1 in sandy loam soil having 0.573 per cent organic carbon. FYM showed marked effect on the reduction of fluchloralin residues when applied @ 30 tonnes ha-1 in sandy loam soil.ThesisItem Unknown FERTILISER MANAGEMENT OF MARGINAL SALT AFFECTED SOIL AT DEVATAJ. GUJARAT(AAU, Anand, 1992) Patel, Motibhai S.; Goswami, K. P.In order to study the physico-chemical properties of soil as well as accumulation of salts at various depths, ten villages of Kheda districts were selected. A soil profile from each of these villages was studied. The soil was found to be marginally saline-alkali, still fit for cultivation further deterioration could be stopped by proper management and reclamation strategy on this soil. A series of field experiments were conducted at the agricultural university during Kharif and Rabi seasons of 1987-88 and 1988-89 using paddy and wheat as indicator crops in rotation. The fields were first treated with gypsum or FYM or gypsum + FYM and super imposed with.four levels of fertilizers N and three levels of phosphours (1) The overall results showed that application of gypsum or FYM have significantly reduced the pH over control during all the crops and both the depths of the soil. (2) The effectiveness in lowering the soil pH and EC was gypsum + FYM > Gypsum > FYM. (3) Fertilizer-N and P2O5 did not change the soil pH or EC significantly. (4) Water soluble Ca2+ generally remained unaffected except when FYM was applied, where also the water soluble Ca2+ was marginal. (5) Water soluble Mg was significantly increased with gypsum or FYM application. (6) Water soluble Na+ was significantly decreased with gypsum, FYM or both applied together during all the four cropping seasons. (7) Water soluble CO3-- and HCO3- remained more or less unchanged. (8) As the soil is marginally saline-alkali, the mobile Cl- and SO4 2- ions had possibly leached down with irrigation water. (9) The exchangeable sodium and sodium percentage were reduced and exchangeable calcium was increased by gypsum application after both the crop. The effectiveness of gypsum and FYM (reclamatory effect) was also reflected in the crop yields. The yields of wheat and paddy had increased in gypsum or FYM treated plots which may have been due to the decreased ESP and increased calcium availability which has also possibly resulted in higher Ca2+ uptakes. (10) Bulk density of the soil was significantly lowered and water holding capacity was increased in FYM treated plots but the effect of gypsum was non significant. (11) The average paddy yield obtained without gypsum was 28.61 and 36.93 q ha-1 during the first and second years with gypsum was 31.8 and 41.8 q ha-1 respectively. (12) Wheat yield : The optimal dose of N + P fertilizer was N160 P80 treatment which gave the highest yields of wheat. (13) The average wheat yield obtained without gypsum was 40.33 and with gypsum it was 43.54 q ha-1 during the first year whereas during the second year it was 63.99 and 69.83 q ha-1 respectively. The effectiveness of phosphorus level on wheat grain yield was pronounced during the first year when the highest yield 22.13 q ha-1 was observed in N160 P80 treatment combination, however, there was no significant effect of P levels during the second year. Nutrient uptake : The nitrogen content of paddy grain or straw and the total uptake were significantly increased by gypsum or FYM application. In wheat, the N content in grain as well as straw were affected significantly by gypsum application, but the effects of FYM application were not significant except in the second year. The N content in paddy grain by nitrogen application was significantly increased with stepping up of nitrogen levels upto N160 which however, appears to have dropped significantly during both the years at 200 kg ha-1 possibly due to lodging. Similar trend in results had also appeared in paddy straw. Uptake of phosphorus was significantly increased in grain and straw of wheat with stepping up of P levels. The uptake of calcium in paddy grain during the second year and straw during both the years were significantly increased by gypsum application. The FYM aplication did not affect calcium uptake significantly in paddy grain but the uptake was significantly increased in straw during both the years. The uptake of calcium by grain and straw was significantly increased at all the N and P levels during both the years. Magnesium and sulphur contents in paddy grain and straw were not affected by gypsum, FYM, N or P levels in both the years, while they were significantly increased due to gypsum in wheat grain, but in wheat straw it was non significant, both due to gypsum as well as FYM treatments.