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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 Open Access EFFECT OF ZINC ENRICHED ORGANICS ON YIELD AND NUTRIENT UPTAKE BY CROPS UNDER WHEATMAIZE (F) CROPPING SEQUENCE(AAU, Anand, 2003) RATHOD, DHARMSINH DIPSINH; Patel, K. P.The present investigation was undertaken to study the comparative efficiency of different Zn-enriched organics on crop yields and increase the fertilizer use efficiency in wheat-maize (F) cropping sequence. The enrichment of different organics was carried out with Zn by composting the locally available organics viz., farm yard manure (FYM), poultry manure (PM), sewage sludge (SS) and biogas slurry (BGS) for six to seven weeks as required to complete the enrichment process. Zinc was added at 2.5 and 5.0 kg ha-1 ttirough 500 kg of organics. The enriched organics were used for field experiment on the pre-identified Zn deficient site at Forage Research Project Farm, GAU, Anand. The treatments of Zn-enriched organics were evaluated as against straight Zn application @ 2.5 kg Zn ha-1 and 5.0 kg Zn ha-1 besides control on wheat var. Lok-1 (Triticum aestivum L.)- for direct effect and on fodder maize var. GM-3 (Zea mays L.) for residual effect. The application of Zn-enriched PM and BGS to wheat in rabi was found beneficial in increasing yields of both wheat as well as maize (fodder) in summer. The Zrvenriched PM and BGS improved average wheat grain yield by about 68 and 49 per cent respectively over control whereas same was higher by 33 and 18 per cent over straight Zn application respectively. It was noticed that the grain and straw yield improvement due to 2.5 kg and 5.0 kg Zn ha-1 enrichment rates with all the organics was comparable within each organic which indicated that the Zn application to wheat could be reduced to one half of the recommended dose of 5 kg Zn ha-1 if the Zn was to be supplemented through any of the organics after its enrichment with Zn. However, Zn enrichment at higher level i.e. 5.0 kg Zn ha-1 was found beneficial with FYM as it registered total dry matter yield of wheat significantly higher by about 13 per cent over 2.5 kg Zn ha-1 Although the straight Zn application increased wheat yield significantly over control, the increase in yield was found comparatively less to that of Zn-enriched organics at both the levels of Zn application. The maize dry matter yield increased significantly due to residual effect of Zn treatments over control. The overall maximum improvement in maize dry matter due to PM and BGS was higher by about 19 and 9 per cent over straight Zn application. The residual effect was found more beneficial under PM when enriched witii Zn at 5 kg ha-1 compared to residual effect due to straight Zn application at same level. Thus, it indicated that the application of Zn-enriched FYM and PM after enrichment at 5 kg Zn ha-1 to wheat was necessary to meet the total Zn requirement in a sequence of wheat-maize (fodder) in order to get significantly higher wheat yield as a direct effect of Zn application and on succeeding maize as residual effect, respectively. The Zn application at 2.5 kg ha-1 was found sufficient when applied after enrichment with BGS and SS for higher wheat and maize yields in the sequence. The Zn-enriched PM and BGS treatments more favorably altered the nutrient contents in grain and straw of wheat than other organics over straight Zn application. The increase in grain and straw yield ultimately caused more removal of major (NPK), secondary (S) and micronutrients (Fe, Zn, Mn and Cu) by wheat due to direct effect and by maize as residual effect due to Zn treatments. The uptake of nutrients was higher under PM and BGS than FYM and SS over straight Zn application. The results further revealed that Zn-enriched PM and BGS enhanced availability of most of the nutrients especially available N, H^O, S and DTPA-extractable micronutrients like Fe and Zn after wheat. Also, the Zn-enriched PM and BGS showed beneficial effect on availability of nutrients with regard to their increase/maintenance in soil after maize due to residual effect. The efficiency of the organics was observed as PM > BGS > SS > FYM for their use after Zn enrichment in wheat-maize (F) cropping sequence. Thus, the overall findings suggested the importance and practical utility of the Zn enrichment technique for organics in integrated nutrient management to maintain fertility and crop productivity of the Zn-deficient soil.ThesisItem Open Access EFFECT OF ZINC AND IRON ENRICHED FYM ON YIELD AND REMOVAL OF NUTRIENTS UNDER MUSTARD-SORGHUM (F) CROP SEQUENCE(AAU, Anand, 2003) MEENA, MAHESH CHAND; Patel, K. P.The present investigation was undertaken to study the comparative efficiency of Zn and Fe enriched FYM on crop yields and nutrients removal under mustard (var. GM-2) - sorghum(var. S-1049) crop sequence. The enrichment was carried out with two levels of Zn (2.5 and 5.0 kg) and Fe (5 and 10 kg) by composting the locally available farm yard manure (FYM) at 500 kg ha-1 for seven weeks as required to complete the enrichment process. The enriched FYM was used for field experiment on the pre-identified Zn and Fe deficient site at Forage Research Project Farm, GAU, Anand. The treatments of Zn and Fe enriched FYM were evaluated as against straight Zn and Fe application at corresponding rates through inorganic fertilizers in conjunction with FYM at 0, 5 and 10t ha-1 In order to evaluate the effect of S, an additional treatment was also kept to supply S at 20 kg ha-1. The average increase in the seed, straw and total yield due to FYM application was higher by 184, 356 and 539 kg ha-1 respectively over no FYM. The Zn and Fe enriched FYM improved average mustard seed yield by 20 per cent over control whereas it was higher by 11 per cent over straight Zn and Fe application. It was noticed that there was no significant difference in mustard yield due to level of Zn and Fe enrichment and FYM levels. The average yield increase in dry matter of sorghum by 11 per cent was observed due to residual effect of FYM over control The overall maximum improvement in sorghum dry matter due to Zn and Fe enriched FYM was higher by about 9 per cent over straight Zn and Fe application. The residual effect of FYM at10 t ha-1 and Zn and Fe enrichment at 2.5 and 5.0 kg ha-1 was found more beneficial to increase sorghum fodder yield. Further, the nutrients removal was found higher under Zn and Fe enriched FYM treatments. Further, mustard seed quality parameters viz. oil, protein and potential oil yield were found improved under treatments of Zn and Fe enrichment compared to straight application of Zn and Fe. In general, the effects under both the levels of enrichments on different parameters in mustard were more or less similar which indicated to lower down the Zn and Fe supplementation dose by one half of the recommended quantity of 5 and 10 kg ha-1 respectively. The application of S alone was also found beneficial; however, the response by the crops was increased when Zn and Fe application was made after their enrichment along with FYM at 10 t ha-1 The Zn and Fe enriched FYM application either maintained or improved the soil fertility status. The Zn and Fe enriched FYM enhanced availability of most of the nutrients especially available N, S and DTPA-extractable micronutrients like Fe, Zn, Mn and Cu after mustard. Thus, the overall findings suggested the importance and practical utility of the Zn and Fe enrichment technique for organics in integrated nutrient management to maintain fertility and crop productivity of the Zn and Fe deficient soil, besides reduction in use of inorganic fertilizers of the micronutrients.ThesisItem Open Access BEHAVIOUR OF CADMIUM IN SOIL AND ITS ABSORPTION BY PLANTS(AAU, Anand, 2001) Jha, Amrit Kumar; Dalwadi, Mahendra R.Cadmium is emerging as an important pollutant in the field of agriculture particularly in industrial state like Gujarat. The present research was undertaken to study (i) some important factors influencing the Cd availability in soil through an incubation study and (ii) uptake of Cd in a pot culture study. An incubation study consisted of five levels of Cd (0, 2.5, 5.0, 10.0 and 20.0 ppm) in presence of three levels each of P (0, 50 and 100 kg ha-1), FYM (0, 10 and 201 ha-1) and CaCOa (0, 5 and 10%) in three separate series for three incubation periods (30, 60 and 90 days). The pot culture experiment was conducted during Kharif, 1999 by growing chickpea upto flowering and wheat upto maturity stage in a clay and a loamy sand soils of Karvan and Anand with five levels of Cd (0, 2.5, 5.0, 10.0 and 20.0 ppm). The results of incubation study indicated that the availability of Cd increased with increasing levels of its application and the per cent fixation of applied Cd ranged between 25.2 and 14.3 with Cdo and Cd4 Ievels(20 ppm). The availability of Cd was found to decrease with application of increasing rates of P, FYM and CaCOa. Amongst these three, FYM @ 20 t ha-1 most effectively reduced Cd availability. The pot culture study indicated that a significant reduction in the dry weight of whole-plant and plant components of both the crops right from the lower level of Cd application (2.5 ppm). Wheat plant did not show any visual toxic symptoms, whereas chickpea plants showed visual symptoms for Cd toxicity at elevated Cd level. The content and uptake of Cd by plant components were significantly increased with Cd application. Amongst the different plant parts, the order followed for Cd content was: roots > stem > leaves > grain and for Cd uptake it was: stem> leaves > roots > grain. A restricted translocation of Cd from roots to above ground plant parts was noted. The N, Ca, Mg and S content did not differ significantly due to Cd addition but the antagonistic effect of Cd on P, K, Zn and Fe content in plant components was observed. Even after the crop harvest, about 22 to 27 per cent of the total applied Cd remained in available form, indicating possible residual effect also. Particularly, at Cd4 level, it crossed the critical level of 3.0 mg kg-1 suggested for Cd.ThesisItem Open Access FATE OF CHLORPYRIPHOS AND ENDOSULFAN IN SOIL(AAU, Anand, 2003) Dodiya, Vijaykumar C.; Shah, P. G.Chlorpyriphos and endosulfan were applied @ 5.0 μg g-1 soil in a laboratory experiment to study their persistence in sandy and sandy loam soil with and without glucose treatment. Adsorption of these insecticides in the soils and their downward movement in the PVC columns filled with sandy and sandy loam soils were also carried out in the laboratory as well as microplot conditions to work out the risk of ground water pollution. Chlorpyriphos and endosulfan showed first-order dissipation in both sandy and sandy loam soils with and without glucose treatment. The halflife values for chlorpyriphos irrespective of glucose treatment in sandy and sandy loam soils ranged from 10.0 to 10.6 and 14.3 to 14.7 days, respectively. The half-life values for total-endosulfan, α - endosulfan and β - endosulfan in sandy soil without glucose treatment were 35.4, 13.9 and 28.9 days, respectively, the correspondmg values in glucose treated sandy soil were 31.7, 17.4 and 27.4 days. The half-life values for total-endosulfan, α - endosulfan and β - endosulfan in sandy loam soil without glucose treatment were 59.0, 20.6 and 41.8 days, respectively, the corresponding values in glucose treated sandy loam soil were 41.8, 19.4 and 35.4 days. Chlorpyriphos showed biphasic mode of dissipation in sandy soil with and without glucose treatment and in glucose treated sandy loam soil, whereas it was monophasic in case of sandy loam soil without glucose treatment. Total-endosulfan showed monophasic mode of dissipation, α - Endosulfan and β - endosulfan showed biphasic mode of dissipation in glucose treated sandy and sandy loam soils, whereas it was monophasic in case of sandy and sandy loam soils without glucose treatment. Endosulfan on degradation was converted to endosulfan sulphate, which is a persistent metabolite. Degradation of chlorpyriphos and endosulfan enhanced initially with glucose application and it was marginally higher in glucose treated soils as compared to soils without glucose treatment. Adsorption of chlorpyriphos, α - endosulfan and β - endosulfan was studied on sandy and sandy loam soils. Chlorpyriphos showed maximum adsorption on both the soils followed by β - endosulfan and α - endosulfan. Organic matter content of the soil was predominantly responsible for adsorption of the insecticides, which was evident by low KOC values of the insecticides for sandy loam soil. Soil column study carried out for one month period revealed little movement of chlorpyriphos beyond 6 cm depth in sandy loam soil in the laboratory experiment and no movement beyond 6 cm depth in sandy soil in laboratory as well as microplot conditions and in sandy loam soil in microplot condition, however quite low amount of endosulfan reached upto 30 cm soil depth in the laboratory and microplot study in sandy loam soil, while, there was little movement of endosulfan beyond 12 cm depth in sandy soil in laboratory as well as microplot conditions. None of the insecticides were detected in the leachates.ThesisItem Open Access LONG TERM EFFECT OF FYM AND FERTILITY LEVELS ON PROPERTIES OF LOAMY SAND SOIL (Typic Ustochrept) AS WELL AS YIELD AND QUALITY OF CROPS IN A PEARLMILLET-MUSTARD-COWPEA (FODDER) CROPPING SEQUENCE(AAU, Anand, 2002) PATEL, JITENDRAKUMAR ADITBHAI; PATEL, B. K.The physico-chemical and biological properties of soil and yield, quality and nutrient content and uptake by different crops as affected by FYM (0 and 10 t ha-1) and fertility levels [no fertilizer (FL1), 50% (FL2), 100% (FL3) and 150%o (FL4) of the recommended NP] in a pearlmillet-mustard-cowpea (fodder) sequence were evaluated during 1998-1999 and 1999-2000 from a long term experiment being conducted since 1994 at the Micronutrient Project (ICAR), G.A.U.. Anand. Soil samples at different depths of profile (0-15 cm) (D1), 15-30 cm (D2), 30-45 cm (D3), 45-60 cm (D4), 60-75 cm (D5) and 75-90 cm (D6) were collected in 2000 summer after harvest of cowpea (fodder). EFFECT OF FYM Application of FYM @ 10 t ha-1 to kharif pearlmillet had decreased bulk density and increased water holding capacity of soil. Its supplementation also improved availability of total N, P, K, S, Mn and Zn due to increase in organic carbon content of soil in the upper horizon (upto 30 cm). The DTPAextractable Fe in soil at 15-30 cm depth was in a deficient range (<5 mg kg-1). The total microbial biomass carbon and microbial population were improved by about 43, and 8.8 per cent, respectively. The overall increase in seed, straw and total yield of pealmillet was about 42 per cent due to FYM application. The total uptake of all the nutrients was higher under FYM than no FYM. The oil and protein contents of pearlmillet seeds were increased by 6.2 and 12.6 per cent, due to FYM addition, respectively. The increase in seed and straw yields of mustard was to the extent of 16.2 and 6.6 per cent due to FYM over no FYM, respectively. The nitrogen content of mustard seed and straw and S and Mn contents of see4 were significantly improved, while Fe, Zn, Cu contents were lower in seed and straw under FYM than no FYM. The uptake of N, P, K and Fe by seed and straw and thereby total uptake was higher under FYM than no FYM. Similarly, S pptake by seed and total uptake, Mn uptake by straw and total uptake as well as Zn uptake by mustard seed were higher under FYM applied to preceding crop of pearlmillet. The protein (10.1%) and oil (6.6%) contents as well as oil yield (26%) potential were significantly improved due to FYM application. The improvement in fodder yield of cowpea under FYM supplementation was due to increase in'green and dry weight as well as chlorophyll contents. The increase in yield resulted in increase N, K and S contents and uptake by cowpea fodder, while P content and uptake were decreased due to FYM application over no FYM. Among micronutrients, Fe and Cu contents were lower in fodder but their uptake was higher with FYM than no FYM. The protein content of cowpea fodder was increased by 49.8 per cent due to FYM application. EFFECT OF FERTILITY LEVELS The water holding capacity and electrical conductivity of soil were improved due to fertility levels. The available nutrients, especially P was increased, while trends for K, S and Cu were not consistent. Interestingly FL3 (100% recommended) fertility level at 15-30 cm depth gave DTPA Fe < 5 mg kg"', while Zn availability was the maximum. The total microbial biomass carbon content increased upto FL3 and decreased significantly thereafter. The yield attributes in general showed increasing trend with the increasing fertility levels, wherein seed yield of pearlmillet and fodder yield of cowpea were the maximum under FL3, while straw and total yield of pearlmillet and yield of all kinds of mustard were maximum under 150 per cent of the recommended dose of NP. The oil content of pearlmillet and mustard seeds was the maximum at the highest fertility (FL4) level. Similarly protein content of pearlmillet seed and cowpea (fodder) was maximum under FL4 and that of mustard seed under FL3. The uptake of N, P and K by pearlmillet was the highest at the highest fertility level. The S uptake by pearlmillet was the highest at FL4 but in mustard and cowpea it was the highest at FL3. Among different micronutrients, Zn removal was the highest at FL4 in all the three crops, while Fe removal was the highest at the same fertility level under pealmillet only. In case of mustard and cowpea, FL2 and FL3 gave maximum total Fe uptake, respectively.ThesisItem Open Access YIELD AND QUALITY OF CABBAGE {BRASSICA OLERACEA L.VfiiR. CAPITATA) AS INFLUENCED BY INTEGRATED NUTRIENT MANAGEMENT AND ITS RESIDUAL EFFECT ON SUCCEEDING BAJRA(AAU, Anand, 2000) PATEL, Z. N.; PATEL, J. C.An experiment was conducted with a view to know the effects of INM on cabbage-bajra sequence at fixed site for a period of two consecutive years (1998 and 1999) at Horticulture Farm, B.A. College of Agriculture, Anand under middle Gujarat agro-climatic conditions.ThesisItem Open Access Studies on use of zinc-enriched organic manures in integrated nutrient management(AAU, Anand, 2003) Siyolkar, Rajnikant D.; Bhatt, V. R.A pot experiment was conducted to study the efficiency of zinc enriched organic manures with other manurial treatments the yield and chemical compositidn of maize at the Agricultural Chemistry and Soil Science department, Gujarat Agricultural University, Anand Campus, Anand taking fodder maize (Zea mays L.) cv. Gujarat Maize-3 as a test crop during summer season of 2000 on loamy sand soil (Typic Ustochrept). Nineteen different treatments were given, using recommended dose of fertilizer and organic manures viz. Farmyard manure, castor cake, poultry manure and biogas slurry enriched with 25 and 12.5 Kg ZnS04 ha-1 The experiment was laid out using complete randomised design with three replication. The green and dry matter yields were recorded and fodder was analysed for chemical constituents. The soil samples were collected at 30 DAS and after harvest of crop and were analysed for the fertility status. The present study revealed that the application of 50 % N through fertilizer + 50 % N through poultry manure enriched with 25 Kg ZnSO4 ha-1 produced the highest green matter yield but it was at par with biogas slurry, castor cake and poultry manure applied with 25 Kg ZnS04 ha-1 Significantly the highest dry fodder yield was recorded under poultry manure enriched with 25 Kg ZnS04 ha-1. The highest dry root weight values were recorded with same treatment. Application of poultry manure enriched with 25 Kg ZnS04 ha-1 proved to be the best in case of N, K and Zn content and uptake. The highest S content was recorded with RDF + SO4 equivalent to treatment N0.-2. However, differences among the treatments were non- significant in P and Cu content of fodder maize. The maximum removal of N, P, K, S, Zn, Fe, Cu and Mn were observed when poultry manure enriched with 25 Kg ZnS04 ha-1 In root study the variation in N, P and K content and root CEC values were found to be non-significant, while the uptake of N and K were significantly influenced by poultry manure enriched with 25 Kg ZnS04 ha-1 The highest Zn content and uptake values were obtained with the same treatment. While studying the fertility status of the soil after harvest, it was noted that the soil pH, EC, WHC, bulk density, porosity, CEC, available P, K, Cu, Mn content of soil were found to be non-significant, while the organic carbon content, total and available N, available S and available Zn contents were the highest values with the poultry manure enriched with 25 KgZnSO4ha-1 Therefore, it was observed that the application of poultry manure enriched with 25 Kg ZnSO4 ha-1 improved the crop quality and soil fertility as well as sustained the productivity of soil. From the above results and discussion it could be concluded that the application of poultry manure enriched with 25 Kg ZnS04 ha-1 prove to be the best treatment for the best yield and quality of fodder maize on loamy sand soil. It also maintains the fertility of the soil.ThesisItem Open Access Influence of farmyard manure on persistence of dinitroaniline herbicides in soil under mustard crop(AAU, Anand, 2003) Rathod, Pareshkumar Himmatlal; Patel, R. B.Pendimethalin, trifluralin and fluchloralin each were applied @ 0.5 and 1.0 kg ha-1 as a pre-plant incorporation in a field experiment carried out at College Agronomy Farm, B. A. College of Agriculture, Anand under mustard crop during rabi season of the year 2001-02 to study their persistence in a sandy loam soil with and without farmyard manure and to see their residues in mustard plant. Influence of dinitroaniline herbicides, farmyard manure and their interactive effect on the some selected soil properties viz., pH, EC, organic carbon, NO3-N, available P2O5 and available K2O was also studied. Dissipation of pendimethalin, trifluralin and fluchloralin followed first order kinetic reaction with half-life values ranging from 41.81 to 53.76, 39.09 to 43.00 and 39.61 to 47.78 days, respectively. Pendimethalin, trifluralin and fluchloralin showed monophasic mode of dissipation. Farmyard manure incorporation @ 10 t ha' decreased the herbicide residues in a sandy loam soil at all the sampling intervals. Relatively lower half-lives of 44.93 and 41.81 days for pendimethalin; 41.23 and 39.09 days for trifluralin; 39.61 and 43.00 days for fluchloralin each @ 0.5 and 1.0 kg ha-1 respectively were recorded with FYM incorporation. Residues of any of three dinitroaniline herbicides were not detected in mustard seed and straw at harvest. Dinitroaniline herbicides and FYM, singly or in combination did not exert any significant influence on pH, EC, organic carbon status, NO3-N, available P2O5 and available K2O content of soil at all the sampling intervals, except organic carbon status of soil which was significantly increased at 5th, 10th and 30th day of sampling due to incorporation of FYM @ 10 t ha-1 over no FYM. Overall results suggest that application of dinitroaniline group of herbicides tested under present study do not pose any problem of environmental contamination.ThesisItem Open Access POSSIBILITY OF UTILIZING PHOSPHOGYPSUM IN AGRICULTURE AS A SOURCE OF SULPHUR(AAU, Anand, 2001) PRABHUDESAI, SHRIKANT S.; KALYANASUNDARAM, N. K.The rapid growth of industries in states like Gujarat has also brought in the need for proper disposal/management of the industrial, effluent byproduct. The byproducts such as phospiiogypsum can sei-ve as a source of sulphur or calcium if heavy metal contaminants and toxic substances, if any, are kept low through pretreatments. Since 37 per cent of Gujarat soils are deficient in S, such S containing byproducts can meet the large requirement in the state. Looking in to the need to recycle such byproducts in a safe and effective way as soil amendments, the present investigation was undertaken to study three phosphogypsum byproducts of dye industry as axsource of S to crops. A field experiment was conducted on S deficient loamy sand soil (21 kg S ha-1) belonging to Typic ustochrept during kharif and rabi seasons of the years 1998-99 and 1999-2000. The fodder sorghum (var. GFSIH-1) during kharif and mustard (var. Varuna) in rabi seasons were grown as test crops. There were seventeen treatments (4 sources x 2 S levels x 2 periods alongwith one control) replicated three times in a randomized block design. Three phosphogypsum byproducts having concentration of heavy metals as Cd (ND), Cr (10-20 ppm), Ni (10 ppm) and Pb (10 ppm) alongwith the mineral gypsum containing Cd (ND), Cr (20 ppm), Ni (10 ppm) and Pb (10 ppm) were used as sources of sulphur in the experiment to supply 20 kg and 40 kg S ha-1. During the first year of experimentation the sulphur was applied to sixteen treatments for fodder sorghum crop. While, during second year, the fresh application of sulphur was done only in the eight treatments for fodder sorglium crop. The mustard crop was grown on residual effect of sulphur during both the years. Application of 40 kg S ha-1 gave significantly higher yield of both the crops than 20 kg S ha-1 and the control, the latter two treatments being at par in their effect irrespective of sources of S. The yield increase due to 40 kg S ha-1 was distinctly evident in the direct and cumulative effects of S treatments on the first and second sorghum crops and in their first residual effects on-the first and second mustard crops respectively. The second and the third residual effects of S treatments applied to the first crop of sorghum did not show any significant impact on the crop yield even at 40 kg S ha-1 level. There was no adverse effect on account of application of the three phosphogypsum byproducts on plant growth and yield of crops and yields were comparable with mineral gypsum treatments. The effect of treatments on the content and uptake of the nutrients such as N, P, K, Ca, Mg, S, Fe, Mn, Zn and Cu was studied. The S content of sorghum plant, mustard seed and mustard stover increased significantly over the control due to the direct and cumulative effects as well as their residual effects of application of 40 kg S ha-1 whereas the N content of sorghum plant increased due to the direct and cumulative effects of sulphur application at both the levels over control. In general, the application of 40 kg S ha-1 increased the metalic micronutrients content in the plant and it was conspicuous in (he direct and cumulative effects of S treatments and in their first residual effects. The three phosphogypsum byproducts did not increase micronutrient contents in plant more than that of mineral gypsum. The sulphur treatments significantly increased macro- and micronutrient uptake by plants as compared to the control in all the crops. The higher level of S application recorded significantly higher uptake of nutrients than the lower dose. All die sulphur sources were at par with each other in terms of nutrient uptake by crops In general, the Cr, Ni and Pb contents in the plants did not increase significantly due to,the different sulphur treatments in comparison to the control. The Cd was below the detectable limit. However, in accordance with the yield increase due to the S treatments, there was corresponding increase in the uptake of the heavy metals also. The Cr and Ni uptake by the first and second sorghum crops and in addition Pb uptake in the second sorghum crop were significantly increased due to the direct and cumulative effects of 40 kg S ha-1 respectively. The first residual effect of direct and cumulative effect of 40 kg S ha-1 treatments significantly increased Ni uptake in the first mustard crop and Pb uptake in the second mustard crop respectively. There were no significant differences in the uptake of heavy metals by plants due to the application of three phosphogypsum byproducts in comparison to mineral gypsum. No significant differences were observed in pH, EC, OC, available N, P, K and Mg content in soil after harvest of each crop due to different treatments. The Ca and S availability increased in the soil after harvest of first and second sorghum crops due to the direct and cumulative effect of 40 S ha-1 treatments irrespective of the source. Available metalic micronutrients did not vary in their contents in soil due to the 40 kg S ha-1 treatment except increase in Mn after the first sorghum crop, Fe after second sorghum crop,- Cu and Mn after the first mustard crop. Different sources of S were at par in their effect on the available micronutrient contents in soil. The direct and cumulative effects as well as their residual effects of the various treatments did not change the Cd, Cr, Ni and Pb availability in soil alter harvest of each crop. Thus the results of the present investigation indicated that the pretreated phosphogypsum byproducts containing low amounts of heavy metals can be safely used as a source of sulphur in S deficient soils for increasing crop yield.
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