Browsing by Author "Kumar, Vipin"
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ThesisItem Open Access EFFECT OF LONG-TERM CROP ESTABLISHMENT AND RESIDUE MANAGEMENT ON N, P, K, S TRANSFORMATIONS AND SOIL HEALTH UNDER RICE-WHEAT CROPPING SYSTEM(Dr.RPCAU, Pusa, 2021) BORPATRAGOHAIN, BIDISHA; Kumar, VipinThe dominant agricultural system prevailing in the Indo-Gangetic Plain is the cereal based cropping system comprising of rice-wheat. Soil quality and health is in the limelight and considered as a vital component of conservation agriculture towards agricultural sustainability. The main challenges confronted by the farming community of Indo-Gangetic Plain (IGP) in Bihar under intensive conventional tillage rice-wheat based cropping system are shortage of manpower, water, energy; high cost of production, diminishing farm returns and unpredictable climatic conditions. To address these loopholes of conventional system, conservation agriculture management systems of crop production are being established. The implementation of conservation agriculture centered on least soil manipulation, surface crop residues retention with practical crop rotation is the need of the hour. The goal of our research was to study how crop establishment and residue management affected soil health indicators, and yield as well as different fractions of the macronutrients (N, P, K and S) through various crop establishment, tillage practices and crop residue combinations in the cropping system of rice-wheat. A long term experiment was established in collaboration with CIMMYT, India, since Monsoon, 2006 with eight different tillage, crop setup, and residue management combinations. The study was performed during 10th June 2019 to 12th October 2019 and 14th November 2019 to 25th March 2020 (two seasons). The site experiences hot and humid summers and has cold winters. The average rainfall of 1344 mm, 89.7 % (1107.8 mm) of which receives throughout the time of monsoon (mid-June to mid-September) while, the winter North-East monsoon rains are scanty and received during January-February. The soil of the experimental site belongs to order Entisol, texture being sandy loam with alkaline pH (8.86), medium SOC (0.48 %) and soil available N, P, K (205.62, 9.35, 136.10 kg ha-1). The trial was set up Randomized Block Design having eight treatment details replicated thrice within a block. The treatments were: puddled transplanted rice-conventional tillage wheat (T1); Puddled transplanted rice-zero tillage wheat (T2); Zero tillage rice-zero tillage wheat on permanent beds having 100 % crop residues (T3); Zero tillage rice-conventional tillage wheat without residues (T4); Zero tillage rice-zero tillage wheat on permanent bed (without residues) (T5); Zero tillage rice-Zero tillage wheat having 100% crop residues (T6); Direct seeded broadcasted rice-Zero tillage wheat (only rice residue in wheat cycle) (T7); Zero tillage rice with brown manuring-zero tillage wheat (without residues) (T8). The study aimed to assess how treatments affected yield, nutrient absorption, and the transformation of various pools of nitrogen, phosphorus, potassium and sulphur, as well as measure soil health in a rice-wheat system. The following are the findings of the present study which revealed that the adoption of zero tillage and crop residue amplified grain yield of rice by 3.91-15.49% although; treatment T8 showed the greatest improvement (by 15.49 percent) as compared to T1's standard procedures. While, in wheat, of zero tillage and residue retention practices increased the grain yield by 34.13- 63.94% over T1 and highest increment (by 63.94%) was established with T3. Treatments T6, T8, T3, T7, and T5 showed a significant increase in system yield by 33.12%, 32.46%, 31.78%, 22.64% and 21.96%, respectively over conventional practices. The nutrient uptake followed similar trend of yield with rice and wheat. The adoption of zero tillage and residue retention practices T3, T5, T6, T7 and T8 revealed higher total N, P, K, S uptake by rice crop by 38.39-26.00%, 10.25-26.64%, 11.05-31.29% and 10.04-37.70%, respectively over the conventional practice (T1). The total uptake of N, P, K and S by wheat crop was to the tune of 27.33-72.13%, 30.13-73.79%, 27.10-79.72% and 41.63-117.92% over conventional practices (T1) by T3, T4, T5, T6, T7 and T8, respectively. Similarly, total micronutrient uptake cations (Iron, manganese, copper and zinc) by rice crop were boosted with the involvement of zero tillage and residue retention to the tune of 11.12-34.83%, 12.73-37.56%, 9.91-41.77% and 10.04-37.71% over conventional practices for T3, T5, T6, T7 and T8, respectively. Likewise, the total uptake of iron, copper and zinc by wheat crop was to tune of 34.67%, 33.48%, 38.44% and 41.00%, respectively over conventional practices (T1). Different N-fractions in soil were ranked in order of dominance: Total N > Total hydrolysable-N > Non-hydrolysable-N > Hydrolysable ammonical-N > Exchangeable ammonical-N > Amino acid-N > Unidentified-N > Hexoseamine-N > Nitrate-N. The treatment ZTR-ZTW+ R showed the highest forms among most of the N fractions, along with ZTR-ZTW (B) + R and ZTR-ZTW (B) + R and ZTR+BM-ZTW being at par. The major pool of P in the soil was organic-P. Excluding Al-P and Fe-P, all the other forms of P was increased with zero tillage, residue management and brown manuring. The following was the average order of various fractions status of P: Organic-P > Ca-P > Mineral-P > Saloid-P > Fe-P > Al-P. The total-K ranged between 14800.2 mg kg-1 to 15643.0 mg kg-1 due to different treatments. Lattice-K contributed the major fraction of K in soil. Retaining residues on soil surface and zero tillage had increased the amount of all forms of K. The order of the availability of different K forms in the soil is as follows: Total-K > Lattice-K > Non-exchangeable-K > Exchangeable-K > Water soluble-K. The total-S varied from 225.27 to 294.43 mg kg-1 due to different treatments. Organically bound-S contributed the major fraction of S in soil. Retaining residues on soil surface and zero tillage had increased the amount of all form of S except residual-S. The availability of different S pools was in the order: total-S > organically bound-S > residual-S > inorganically bound-S > distilled water soluble-S > sulphate-S. The correlation coefficient study specified that all the fractions of N, P, K and S were in dynamic equilibrium showing positive significant relationship with the majority of plant and soil attributes. The pH and EC content at the commencement of the experiment in 2006 were higher as compared to values obtained under conservation agriculture plots. However, when conservation techniques were used, available macro and micronutrients were enhanced compared to their baseline data which were obtained before the trial began in 2006. Involvement of CA practices significantly altered the soil health parameters viz. soil physico-chemical and biological properties. After one cycle of rice-wheat, conservation agriculture increased the wet aggregate stability (%). The CA (ZTR-ZTW (B)+R, ZTR-ZTW(B)-R, ZTR-ZTW+R, DSR-ZTW+R.R and ZTR+BM-ZTW) practices recorded increase to the tune of 38.15%, 17.24%, 34.48%, 28.87% and 32.75%, respectively over the control. The CA practices increased the soil organic carbon with time as the increment in SOC (0- 15 cm soil depth) with conservation agriculture adoption (T2, T3, T4, T5, T6, T7 and T8) was by 16.37- 86.04% over conventional practices. The active carbon varied between 165.0 mg kg-1 in conventional plot to 373.3 mg kg−1 in ZTR-ZTW (B) +R. The treatment ZTR-ZTW (B) +R was significantly superior and at par with ZTR-ZTW+R (62.4 mg kg−1) and ZTR+BM-ZTW (61.6 mg kg−1). The magnitude of increase in active carbon was 4.36%, 15.57%, 46.66%, 95.81%, 97.87%, 106.06% and 126.24% over control. Soil respiration varied between 1.53 CO2 mg g−1soil in control plot to 1.88 CO2 mg g−1soil in ZTR-ZTW (B) +R. The magnitude of increase in soil respiration was 1.30%, 4.57%, 7.84%, 10.45%, 16.33%, 18.30% and 22.87% over control in treatments ZTR-CTW-R, PTR-ZTW, ZTR-ZTW(B)-R, DSR-ZTW+R.R, ZTR+BM-ZTW, ZTR-ZTW+R and ZTR-ZTW(B)+R, respectively. The magnitude of increase in ACE protein was 6.37%, 9.96%, 12.75%, 19.92%, 23.90%, 26.69% and 28.29 % over control in PTR-ZTW, ZTR-CTW-R, ZTR-ZTW(B)-R, DSR-ZTW+R.R, ZTR-ZTW+R, ZTR-ZTW(B)+R and ZTR+BM-ZTW, respectively. Hence, conservational agricultural system contributed to higher production of ACE protein. The ZT with residue retention was found to be superior over CT due to congenial crop-soil environment. Thus, long term effect of crop establishment with varying degrees of residue retention improved different pools of soil nitrogen, phosphorus, potassium and sulphur; soil health parameters and thereby, enhanced the soil health in the long run.ThesisItem Open Access Effect of NPK, FYM and Zn application on transformation of Zn, biological properties and nutrient availability under rice-wheat cropping system in calcareous soil(RPCAU, Pusa, 2023) KACHHAP, AANCHAL; Kumar, VipinThe present study aimed to investigate the effect of NPK, FYM, and Zn application within a RWCS in calcareous soil on various aspects, including yield, nutrient uptake, chemical properties, and biological characteristics of post-harvest soil of second wheat crop in the year 2023. Additionally, the study examined different fractions of zinc in the soil and their correlations with each other, as well as with yield, nutrient uptake, and available zinc content. The research was conducted as a field experiment that commenced during the kharif season of 2021 at the Pusa Research Farm of RPCAU Samastipur, Bihar. The experimental layout followed a randomized block design comprising ten treatments replicated three times. These treatments included a range of conditions: T1 as the absolute control, T2 with RDF (Recommended Dose of Fertilizers), T3 with RDF and FYM @ 5 t ha-1, T4 with RDF and foliar spray of 0.5% ZnSO4, T5 with RDF and 5 kg Zn ha-1, T6 with RDF and Geoxol.com @ 40 kg ha-1, and T7, T8, T9, T10 similar to T2, T3, T4, T5, respectively, but with an increased RDF level of 125%. Among these treatments, T10 (125% RDF + 5 kg Zn ha-1) exhibited the highest yield of 5.21 t ha-1 and 4.64 t ha-1 with grain yield response of about 6.3 to 27.1 and 0.21 to 0.90 per cent in rice and wheat crop respectively. However, when considering nutrient uptake, T8 (125% RDF + FYM @5 t ha-1) showed the greatest total nutrient uptake, and it was statistically similar to treatments involving increased fertility levels in combination with organic supplementation and zinc sources. Remarkably, substantial nutrient availability (N, P, K, S, and Zn) was detected in treatments with enhanced fertility levels, both independently and in various combinations. Moreover, treatment T8 demonstrated noteworthy dominance in biological properties, indicating that FYM and higher fertilizer levels played a pivotal role in stimulating microbial growth. This heightened response was most pronounced in treatments involving 125% RDF, either alone or in combination, mainly due to the initial nutrient deficiency of the soil. Analyzing different zinc fractions in the post-harvest soil indicated that the water-soluble and exchangeable forms were minimal, while the residual form was predominant revealing that the majority of total zinc resided in the residual form. Interestingly, positive and significant correlations were observed among yield, nutrient uptake, and available zinc content. The order of dominance of different zinc fractions in the soil was: Residual-Zn > Organically bound-Zn > Zn bound to crystalline oxide > Zn bound to amorphous oxide > Complexed-Zn > Water soluble plus exchangeable-Zn. These findings inform agricultural practices and soil management strategies to farmers by emphasizing the benefits of balanced NPK fertilization with organic supplementation and zinc for improved crop yields. They underscore the importance of addressing micronutrient deficiencies, particularly zinc, and highlight the role of organic matter in enhancing soil health. Additionally, the study offers insights into nutrient build-up and zinc distribution, guiding more efficient soil fertility strategies. Overall, these findings promote a holistic approach to soil and nutrient management, enhancing sustainability in agriculture.ThesisItem Open Access Effect of organic amendments on growth and yield of mustard grown in chromium contaminated soils(Department of Soil Science and Agricultural Chemistry Institute of Agricultural Sciences Banaras Hindu University Varanasi, 2018) Kumar, Vipin; Sharma, P.K.Due to wide industrial use of chromium, it is considered a serious environmental pollutant. Chromium exists in several oxidation states (-2 to +6), but hexavalent chromate [Cr (VI)] and trivalent chromite [Cr (III)] forms are the most common and stable in the natural environment. Cr (VI) in the forms of chromate (CrO42-), dichromate (Cr2O72-), and CrO3 are considered the most toxic forms of chromium, as it presents high oxidizing potential, high solubility, and mobility across the membranes in living organisms and in the environment. Several organic amendments can improve phytostabilization and the production of plant by decreasing the solubility, leaching and bioavailability of trace elements. However very few comparative studies have been performed so far and the choice of a particular organic amendment in assisted phytostabilization strategies often remain empirical.A pot experiment was conducted to study the effect of organic amendments on growth and yield of mustard grown in chromium contaminated soilsin Department of Soil Science and Agricultural Chemistry, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi during 2015-16 and 2016-17. Five levels of chromium viz. 0, 20, 40, 60 and 80 ppm with and without three organic amendments viz. vermicompost @ 5 ton ha-1, farm yard manure @ 10 ton ha-1 and sewage sludge @ 20 ton ha-1 treatment were applied in the experiment. It was observed that chromium has negative impact on growth and yield of mustard. Organic amendments found better option to mitigate chromium toxicities on growth and yield of mustard as they supply organic matter which enhances microbial population and simultaneously reduces the toxicity of chromium by decreasing availability of chromium in soil. Among the organic amendments vermicompost exhibited superior efficacy in alleviating the effect of chromium. It was followed by farm yard manure while sewage sludge was least effective in mitigating the toxic effect of chromium.ThesisItem Open Access Interaction of calreticulin of haemonchus contortus with goat peripheral blood mononuclear cells(NANAJI DESHMUKH VITERINARY SCIENCE UNIVERSITY, JABALPUR, 2007) Kumar, Vipin; Joshi, Dr. P.Interaction of calreticulin of haemonchus contortus with goat peripheral blood mononuclear cellsThesisItem Open Access Interaction of calreticulin of haemonchus contortus with goat peripheral blood mononuclear cells(jnkvv jabalpur, 2007) Kumar, Vipin; Gehlaut, B.S.ThesisItem Open Access Optimizing Levels of Fertilizers and Spacing on Sugarcane Genotypes and Soil Nitrogen Fractions under Calcareous Soil(DRPCAU, PUSA, 2021) MOURYA, BUDDHA PRIYA; Kumar, VipinA field experiment was conducted to optimize the levels of fertilizer and spacing for better performance of sugarcane genotypes and soil nitrogen fractions under Calcareous Soil during 2019-20 at Dr Rajendra Prasad Central Agricultural University Bihar. The treatment combination comprised two spacings (row to row-90 cm and 120 cm), three levels of fertilizers (100 % NPK of RDF, 125 % of NPK of RDF and 150 % of NPK of RDF) and six different sugarcane genotypes (CoLk 15466, CoLk 15467, CoP 15436, CoSe 15452, CoSe 15455, CoLk 94184) with having a total of thirty-six treatment combinations and three replications. The recommended dose of fertilizer 150:85:60 kg N: P2O5: K2O ha-1 was applied through urea, SSP and MOP. The half dose of N was used through basal dose, and the remaining half was used in two equal split doses. The P and K were applied as basal doses. Sugarcane crop was planted during the spring (February 2020) season. The effect of row spacing on germination at 30 DAP and 45 DAP was statistically non-significant and significant, respectively. Germination per cent was highest in treatment with 90 cm of row spacing compared to 120 cm of the row spacing at both the stages of plant growth, i.e., at 30 DAP (27.8%) and 45 DAP (31.6%). At 30 DAP, fertilizer levels didn’t significantly affect, whereas, at 45 DAP, the effect was significant. The highest germination per cent at 30 DAP (27.8%) was recorded in treatment with 150 % NPK of RDF, whereas the highest germination per cent at 45 DAP (32.4%) was recorded with 100 % NPK of RDF. At last, coming to genotype, it was concluded that at both the stages of plant growth, i.e., at 30 DAP (30.7%) and 45 DAP (34.2%), genotype CoP 15436 recorded the highest germination per cent (30.7%). Also, at both stages, the effect of genotype on germination per cent was found to be significant. The effect of row spacing on plant population at both the stages of crop growth, i.e., at 120 DAP and 150 DAP, was statistically significant. Fertilizer treatment with 150 % NPK of RDF showed significantly the highest effect on plant population at both stages of plant growth. Genotype CoP 15436 also showed significantly superior results over the rest of the genotypes concerning plant population at both stages of plant growth. Significantly higher cane yield (85.0 t ha-1) was recorded in treatment with a narrow spacing of 90 cm compared to cane yield (74.8 t ha-1) in treatment with wider row spacing of 120 cm. Significantly higher juice recovery was found in treatment with 90 cm spacing (64.88 %) than 120 cm spacing (63.16 %). The effect of spacing on available soil nitrogen was observed to be non-significant. Availability of nutrients in the soil is strongly affected by 120 cm row spacing, 150% NPK of RDF and genotype CoLk 15467 and hence proved beneficial for improving the fertility status of the soil. In the case of nutrient uptake by sugarcane plant, we concluded that 90 cm row spacing, 150% NPK of RDF and either of the three genotypes viz., CoLk 15466, CoP 15436, CoSe 15452 proved best which enabled the plant to utilize the nutrients from the soil efficiently. The effect of spacing on nitrate-nitrogen was non-significant. However, levels of fertilizer were found to have a statistically significant impact on nitrate-nitrogen fraction. Significantly highest nitrate-nitrogen content was observed in treatment with 150% NPK of RDF (23.6 mg Kg-1). Genotype was also found to have a significant effect on nitrate-nitrogen fraction. Genotype CoLk 15467 received the significantly highest value (23.9 mg Kg-1) for nitrate-nitrogen. While looking over data obtained on soil nitrogen fractions, whether it be inorganic fractions (NO3-- N + Exchangeable NH4+-N) or organic fractions (Hydrolyzable ammonical-Nitrogen + Hexose amine-Nitrogen + Amino acid-N + Unidentified-N), we concluded that 120 cm row spacing, 150% NPK of RDF and genotype CoLk 94184 supposed to maintain the nitrogen dynamics in the soil.ThesisItem Open Access Screening of maize varieties to zinc stress in calcareouus soil.(Rajendra Agricultural University, Pusa (Samastipur), 2014) Rupali; Kumar, VipinA field experiment was conducted during the rabi season of 2012-13 in highly calcareous sandy loam soil, deficient in available Zn (0.56 mg kg-1) at Research Farm, Rajendra Agricultural University, Pusa to study the screening of maize varieties to zinc stress in calcareous soil. The experiment was laid out in split plot design assigning Zn levels ( 0, 5 and 10 Kg Zn ha-1 ) in main and twelve maize varieties ( Shaktiman 1, Shaktiman 2, Shaktiman 3, Shaktiman 5, Laxmi, Swan, Devki, Hemant , NK 6607, Raja 909, Rasitopless and Rasi 3022) in sub plot and replicated thrice. The varieties responded differently to Zn application with respect to grain and straw as well as concentration and their uptake of zinc nutrition. The average grain yield at 5.0 and 10.0 kg Zn ha-1 were statistically at par in composite varieties, but in case of hybrid and quality protein maize 10 kg Zn ha-1 has optimum. Hence, 10.0 kg Zn ha-1 was rated as optimum level for most of the varieties, only for the composite varieties may be rated 5.0 kg Zn ha-1 level for maize production. On the basis of percent response (figure in Parenthesis) to grain yield the relative susceptibility of maize varieties to Zn stress were as follow. Shaktiman 5 > (32.9) Rasi 3022 > (27.5) Raja 909> (26.5) Rasitopless > (26.3) NK 6607 > (24.5) Shaktimn 1 > (19.9) Shaktiman 3> (17.7) Shaktiman 2> (16.9) Devki > (16.5) Laxmi > (12.3) Swan > (10.8) Hemant (10.0) The varieties giving highest magnitude of response were rated to be most inefficient and those giving least response were classified as most efficient. On the basis of Zinc efficiency index and Zinc efficiency, out of twelve maize varieties screened under zinc stress and sufficient condition the Laxmi, Swan, Devki and Hemant were found to be efficient and Raja 909, Shaktiman 5, NK 6607, Rasi 3022 and Rasitopless varieties were found to be inefficient.ThesisItem Open Access Screening of rice genotypes for sodicity tolerance under calcareous soil(DRPCAU, Pusa, 2020) Upadhay, Ajay Kumar; Kumar, VipinThe present study was undertaken to study the “SCREENING OF RICE GENOTYPES FOR SODICITY TOLERANCE UNDER CALCAREOUS SOIL” during 2019-2020 at the research farm of Dr. Rajendra Prasad Central Agricultural University, Pusa, Bihar.The research trial was designed in RBD with 30 plots in each of 3 replication. In farm 30 rice genotypes was taken for evaluating valuable parameters such as yield attributes, nutrient uptake, physiological attributes and sodium – potassium ratio at tillering and preflowering stages to identify or select tolerant and susceptible rice genotypes under salt stress condition. Initial soil parameters were measured to know the quality of soil. Based on results, it was noticed that genotypes such as Rajendra Mahsuri, GPV 1, GPV 3 perform better w.r.t physiological attributes and sodium potassium ratio , yield attributes and nutrient uptake while Rajendra bhagwati, prabhat and Rasi perform poor in these aspect of research.ThesisItem Open Access Studies on the effect of Vitamin E supplementation on the potentiation of immunity in herpesvirus of turkeys vaccinated and challenged chickens(College of Veterinary Sciences Chaudhary Charan Singh Haryana Agricultural University Hisar, 1996) Kumar, Vipin; Pruthi, A.KThesisItem Open Access Study on milk safety status: assessment of common adulterants in market milk of Punjab(GADVASU, Ludhiana, 2018-02-21) Kumar, Vipin; Aulakh, R.S.Comparative appraisal of analytical sensitivity of various milk adulteration kits and biochemical methods revealed that commercial kit (D), biochemical tests (A), institutional kit (B), commercial kit (E) and institutional kit (C) were found to be most sensitive for 8, 7, 4, 2 and 1 milk adulterants, respectively. Out of 732 milk samples collected from markets of Punjab, 14 (1.91%) for formaldehyde, 93 (12.70%) for neutralizer, 160 (21.86%) for water, 14 (1.91%) for urea, 6 (0.82%) for starch, 108 (14.75%) for salt, 8 (1.09%) for cane sugar, 17 (2.32%) for skim milk powder and 16 (2.19%) for detergent were found to be positive on qualitative assessment. No sample was found to be adulterated with hydrogen peroxide, glucose and calcium carbonate. Quantitative estimation of all samples found positive in preliminary screening was performed for formaldehyde, urea, detergent, starch and cane sugar using HPLC, colorimetric, spectro-photometric and titration based methodology, respectively. In total, 160 milk samples were analyzed to assess microbial safety of milk. Results showed that milk sold from shops and pasteurized milk of organized sector is associated with lower levels of risk, while raw milk and milk sold by door-to-door vendors posed higher levels of risk. Out of total, 80 raw milk samples were taken to assess milk quality. Results of Somatic Cell Count revealed that milk samples collected from Amritsar and Bhatinda were related with lower risk, while from Nawanshahr and Ferozepur posed higher risk. On the basis of Preliminary Incubation Count, all the collected milk samples were associated with higher risk. Results of Laboratory Pasteurization Count showed that milk samples from Ferozepur were related with lower risk and Gurdaspur, Ropar, Nawanshahr, Amritsar, Jalandhar, Faridkot, Bhatinda and Moga were associated with higher risk. A simple, low-cost, rapid, reproducible and field applicable smart phone based colorimetric method was also standardized and validated for the quantitative determination of neutralizer in milk samples.ThesisItem Open Access Zinc and Carbon pools under long term conservation agriculture with Rice-Wheat cropping system in Calcareous Soil(Dr. Rajendra Prasad Central Agricultural University, Pusa (Samastipur), 2018) Dash, Bishnu Prasad; Kumar, VipinA long-term experiment involving various combinations of tillage, crop establishment and residue management practices in a rice-wheat rotation has been continuing since 2006 at South Pangabri plot of Crop Research Center, Dr. Rajendra Prasad Central Agricultural University, Pusa, Samastipur, Bihar. The climate of this region is sub-tropical humid. The experimental site is situated at 25°30' N latitude, 85°40' E longitude and 52.00 meter above mean sea level. Conservation agriculture based on principles of minimum soil disturbance, residue retention on soil surface and crop diversification improves soil organic carbon and available nutrients status which plays a crucial role in sustaining the soil health. Therefore present study entitled “Zinc and Carbon pools under long-term conservation agriculture with Rice-Wheat cropping system in Calcareous soil", was undertaken during kharif 2016 and rabi 2016-17. The objectives were to understand the effect of conservation agriculture on rice and wheat yield and uptake of nutrients; zinc fractions in soil; different forms of carbon in soil, and; soil chemical properties. The experiment was laid out in a randomized block design with 8 treatments with different crop establishment practices and residue retention in rice and wheat. Rice grain yield in conventional tillage practices in both rice and wheat crop [PTR-CTW] was significantly lower than most of the treatments. Higher grain and straw yield of both rice and wheat was obtained in zero tillage wheat crop preceded by zero tillage rice with residue retention in both the crops. Total soil organic carbon (TOC) in 0-5 cm soil depth, under zero tillage rice- zero tillage wheat on bed with residue [ZTR-ZTW(B)+R] and zero tillage rice-zero tillage wheat with residue[ZTR-ZTW+R] were 23.79g kg-1 and 23.11g kg-1 respectively, which were statistically at par to each other These values were significantly higher over conventional tillage [PTR-CTW] treatments (10.55 gkg-1). TOC of 5-15cm and 15-30cm depth under ZTR-ZTW(B)+R treatment was also significantly superior over PTR-CTW. The Walkley and Black carbon (WBC) under treatment ZTR-ZTW+R was 1.10% which was 72.9 % higher over PTR-CTW at 0-5 cm depth. Different fractions of oxidisable carbon of varying lability in 0-5cm, 5-15 cm and 15-30 cm was found in the order: Non-labile > Very labile > Labile > Less labile. The content of TOC, WBC, Microbial biomass carbon and KMnO4 - C decreased with increase in soil depth while that of soil inorganic carbon increased. Correlation study among different fractions of oxidisable carbon indicated that all forms of oxidisable carbon were in dynamic equilibrium and positively and significantly correlated with each other. The water soluble and exchangeable fractions of zinc under ZTR-ZTW(B)+R and ZTR-R were statistically at par to each other and were statistically superior over PTR-CTW. Correlation study among different fractions of zinc and soil properties like organic carbon, CaCO3 content and grain and straw yield,zinc uptake by rice and wheat indicated that the Water soluble + Exchangeable-Zn, Complexed-Zn and Organically bound-Zn, Residual-Zn were positively and significantly correlated with all the parameters except CaCO3 content of soil. The path analysis was carried out to study the direct and indirect effect of different zinc fractions towards available zinc in soil and zinc uptake by both the crops. Different fractions of zinc in soil was found in the dominance order: Residual-Zn > Crystalline oxide bound- Zn >Complexed-Zn > Amorphous oxide bound- Zn > organically bound-Zn > Water soluble + Exchangeable-Zn. It may be concluded that zero tillage rice followed by zero tillage wheat with residue retention in rice had similar system rice equivalent yield. The different organic carbon fractions e.g. TOC, WBC, MBC, POC and the different labile pools were similar in ZTR-ZTW(B)+R and ZTR-ZTW +R treatments. The values were significantly higher as compared to other treatments. The dissolution of free CaCO3 in both these treatmentswere also significantly higher as compared to the other treatments. Water soluble + Exchangeable-Zn, Complexed-Zn and Organically bound-Zn were dominant fractions of zinc in soil that contributed most towards uptake of Zn by rice and wheat crop.