Chopped Rice Straw Research Articles

A Synergetic Approach of Agricultural Waste Management through vermicomposting

The present study was conducted to investigate the vermicomposting potential of epigeic earthworm, Eisenia foetida for rice straw and cow dung. The experiment comprised of ten treatments T1 - [Chopped Rice straw + cow dung (1:1)] + 1kg worm), T2 - [Unchopped Rice straw + cow dung (1:1)] + 1kg worm), T3 - [Chopped Rice straw + cow dung (1:1)] + 2kg worm), T4 - [Unchopped Rice straw + cow dung (1:1)]+ 2kg worm), T5 - [Chopped Rice straw (70%) + soil (10%) + cow dung (20%) + 1kg worm], T6 - [unchopped Rice straw (70%) + soil (10%) + cow dung (20%) + 1kg worm], T7 - [Chopped Rice straw (70%) + soil (10%) + cow dung (20%) + 2kg worm], T8 - [Unchopped Rice straw (70%) + soil (10%) + cow dung (20%) + 2kg worm], T9 - [cow dung + 1kg worm] and T10 - [cow dung only], single replicate arranged in a randomized block design. The experimental results revealed that out of all the treatments, higher values of N, P and K were observed in T7 - Chopped Rice straw (70%) + soil (10%) + cow dung (20%) + 2 kg worm. The micronutrient content was also found higher in this treatment with higher biomass production. The multiplication of earthworms was significantly higher than only cow dung and other treatments. The vermicompost produced can be of significant value to the end users like farmers for replacement of chemical fertilizers and procuring better prices for the organic produce using such composting material locally available at much lower cost. Vermicomposting might prove to be a positive approach towards sustainable waste management system.

Semi-continuous fermentation of chopped rice straw in a solid-state anaerobic digester: Influences of the tank height-to-diameter ratio, solid-state bed concentration, and leachate recirculation ratio

Chopped rice straw fermentation in solid-state anaerobic digesters (SS-ADs) is a viable path for biogas generation. Thus, three fermentation test series in typical anaerobic digesters were operated to investigate the effects of the external surface area, permeability, and liquid fluidity of the solid-state bed (SSB) in improving anaerobic digestion, as determined by varying the tank height-to-diameter (H:D) ratio, SSB concentration, and leachate recirculation ratio (RR), respectively. In Series A, the H:D ratio impacted the modulation of digestion progress, including biogas generation, volatile fatty acids release, and lignocellulosic degradation. In Series B, the use of an SSB concentration below the inflection threshold (10.7 %–13.3%) for biogas production decline resulted in the highest methane yield and average methane content. In Series C, a 25.0% RR increased methane production significantly (P < 0.01) in both the semi-continuous fermentation SS-AD and downward plug-flow anaerobic digester (DPAD). Accordingly, energy flow analysis revealed that the DPAD produced 19.3% more net energy than the liquid anaerobic digester.

Requirements Of Balling Chopped Rice Straw

This study aimed to identify the effect of the rice straw chopping process on the bales storage capacity. Chopping process of straw rice was carried out under three drum speeds, three feeding rates and three moisture contents of straw. Baling process was used to press chopped straw with three frequency speeds of plunger to press chopped straw, three feeding rates for chopped rice straw and different cutting lengths for chopped rice straw. The results were obtained the lowest average cutting length was7.88 mm with increasing speed of drum from 4.71 to 10.5m/s, and the minimum moisture content at 12%. The highest bale density was 144.6 kg / m³,under the frequency of press speed 0.45 m /s, for cutting length averages of less than 10 mm. The lowest storage capacity was 16.46 m³/fed, with a maximum compressing speed of 0.45 m /s and a feeding rate of 1.5Mg /h with the use of cutting averages less than 10mm. For the chopping process, the lowest energy requirement was8.9 kW.h/Mg at 4.71m/s and 12% moisture content with feed rate of 1.5Mg /h. Otherwise for the baling process, the lowest energy requirement was 5.67 kW.h /Mg at a compression speed of 0.24 m /s, feed rate of 3Mg/h and average cutting lengths greater than 20.5mm. The lowest production cost obtained when chopping straw was79.7LE /Mg with a speed of 4.71m/s, a moisture content of 12% and a feed rate of 1.5 Mg/h. The lowest production cost obtained when baling chopped straw was 98.5LE/ Mg with a speed of 0.24m /s and feeding rate of 3Mg /h.

Effect of organic mulch and LEDs light colors on green bean plants (Phaseolus vulgaris L.)

Studying the positive role of applying organic mulch and different colors of LEDs light, on the growth and yield of green bean plants, were carried out during 2019/2020 and 2020/2021 seasons, at a privet farm within Suez Governorate. Seedlings of Bronco cultivar were transplanted at the 15th of October of both seasons. Two types of organic mulch i.e., chopped maize straw and chopped rice straw, addition to bare soil (control) were tested as a soil mulch treatment (factor 1). In addition, LEDs light colors i.e., red, blue and "red + blue" and without LED light were also tested (factor 2). Finally, interaction between both studied factors was also studied. Studied factors were arranged in split plot design with three replicates. Organic soil mulches were arranged in the main plots. However, LEDs light colors were arranged within the sub main plots. Vegetative growth parameters i.e., plant height, number of leaves/plant, stem diameter, number of branches/plant, fresh and dry weight of plants were measured. Moreover, percentages of nitrogen, phosphorus and potassium contents in leaves, as well as, chlorophyll reading (SPAD) were also measured. In addition, pod characteristics i.e., number of pods/plant, average pod weight and fiber content in pods, were studied as well. Finally, both early and total yield of green bean were studied. Changes in soil temperature under organic mulch treatments, as well as, bare soil were daily measured during the growing seasons. Results indicated that, in general, applying tested types of organic mulch modified soil temperature. Moreover, both tested factors were enhanced measured characters of vegetative growth, leaves content of nitrogen, phosphorus and potassium, as well as yield and its components. Furthermore, both treatments of chopped maize straw and "red + blue" LEDs light, as well as the interaction between both treatments were the most suitable for increasing productivity and quality of green bean plants.

Some Nutrients Availability in Rice Soil under Utilization of Organic and Inorganic Fertilizers

A field experiment was conducted at the Experimental Farm of Sakha Agricultural Research Station; Kafr El-Sheikh, throughout the summer season of 2017 and 2018 to examine the nutrients status in rice soils under the utilization of organic and inorganic fertilizers. Egyptian hybrid rice one (EHR1) variety was used. The experiment was laid out in a split-plot design with four replications, where main plots were assigned to NPK fertilizer treatment and sub-plots were allocated to organic material treatments. The NPK fertilizer’s treatments were full dose, 2/3, 1/3 of NPK recommended doses and control (without any mineral fertilizers application). The recommended doses of NPK are 165 kg N ha-1, 36 kg P2O5 ha-1 and 58 kg K2O ha-1. The organic material treatments were control (without any organic materials application), rice straw compost, farm yard manure, chopped rice straw and mixture of chopped rice straw and farm yard manure (1:1). The application rate of the organic materials was 7 tons ha-1 for each treatment. The studied characteristics were the available ammonium (ppm), nitrate (ppm), phosphorus (ppm), potassium (ppm), zinc (ppm) as well as grain yield (t ha-1). Soil samples were collected at 30, 45 and 60 days after transplanting (DAT) and after rice harvest during the two study seasons. The available nutrients in soil tended to increase as NPK fertilizer levels increased and by the application of organic materials. Available NH4 markedly increased after flooding reached its high peak at 30 DAT and then declined to the minimum values at harvest. The high peak of NO3 was observed at 30 DAT, then started to decline afterward and reached its minimum values at harvest. The highest amount of available K was obtained at 45 DAT and then decreased continuously with crop growth, reaching the lowest values at harvest time. Current data reveal that the maximum available Zn was found at 30 DAT. The application of a full recommended dose of NPK mineral fertilizer combined with compost or farm yard manure and compost alone produced the highest values of grain yield.

Effects of the natural sweetener rebaudioside A on intake, nutrient digestion, rumen fermentation, and blood biochemical parameters in adult goats during summer.

The effects of dietary rebaudioside A inclusion on feed intake, digestion of nutrients, rumen fermentation, and blood biochemical parameters of goats were evaluated in a replicated 3×3 Latin square study. Nine adult goats during summer were fed a basal forage/concentrate-based diet and the forage was chopped rice straw. The three dietary treatments were 0, 350, and 700mg rebaudioside A per kg chopped rice straw on a DM basis. No significant improvement was observed in dry matter intake (DMI) of forage and diet among treatments. Nutrient digestibility of DM and organic matter (OM) showed a significant trend (p<.10) across groups. Rebaudioside A inclusion significantly (p<.01) increased the concentration of total volatile fatty acids in the rumen, however, there were no differences in concentration of ruminal ammonia, and molar proportions of acetate, propionate, and butyrate. About blood metabolites, increasing rebaudioside A in the diet caused a quadratic response in glucose and total protein, and albumin concentrations. Under the conditions of this study, supplementation with rebaudioside A at 350 and 700mg/kg forage did not improve consumption of rice straw-based diet in adult goats in summer. However, the responses in digestibility, rumen fermentation, and blood metabolites appear to indicate the potential of rebaudioside A as a bio-active substance in goats.

Wastewater remediation of heavy metals and pesticides using rice straw and/or zeolite as bioadsorbents and assessment of treated wastewater reuse in the culture of Nile tilapia (Oreochromis niloticus).

The remediation of wastewater (WW) is a promising solution for limited water sources. This study aimed to evaluate rice straw (RS) and zeolite (Z) as bioadsorbents for the removal of pollutants, including heavy metals (HMs) (cadmium [Cd], nickel [Ni], and lead [Pb]) and malathion (PC), from WW and to assess the suitability of reusing remediated WW in fish rearing units. A total of 11 treatment groups with 3 replicates each were designed with different combinations of RS and/or Z for the treatment of real WW contaminated with HMs and malathion, where the WW remained in contact with the adsorbents for 24h. Different remediated WWs were used for rearing Nile tilapia (Oreochromis niloticus), which were randomly allocated into 33 glass aquaria representing 11 treatments with 3 replicates each for 30days. The best remediation efficiency was achieved using a mixture of whole RS (WRS), chopped RS (CRS), and Z (HM-PC-WRS-CRS-Z group), with removal percentages of 92%, 95%, 96%, and 99% for Cd, Ni, Pb, and malathion, respectively. The health status of the aquatic ecosystems was assessed through blood tests to characterize biochemical parameters and through pathological changes of cultured O. niloticus reared in treated WW. A significant (P˂0.05) effect on the blood biochemistry of fish reared in treated WW was found and better biochemical and histologic architecture was observed than that of fish reared in untreated WW. A novel mixture of WRS, CRS, and Z could possibly be a promising low-cost adsorbent for wastewater treatment. Graphical abstract.

EFFECT OF CHOPPED RICE STRAW AND FOLIAR APPLICATION OF POTASSIUM AND PHOSPHORUS ON GROWTH, YIELD AND TUBEROUS ROOT QUALITY OF SWEET POTATO (Ipomoea batatas L.) GROWING AT LATE SUMMER SEASONS UNDER CLAY SOIL CONDITIONS

Two field experiments were carried out at the experimental Farm, Faculty of Technology and Development(Ghazala farm), Zagazig university El Sharkia Governorate, Egypt during the summer season of 2017 and 2018 to investigate the effect of chopped rice straw and foliar spray with potassium and phosphorus fertilizers sweet potato cv. Minufiya 6 growing at summer seasons in clay soil, on growth, yield and quality. The experiment was set out in a randomized complete blocks design where including seven treatments, which were chopped, rice straw at 2kg/ridge only and in combinatory with potassium and phosphorus at 2 and 4 mll-1as well as control. The results indicated that application of chopped rice straw at the rate of 4kg/ridge with foliar spray of potassium and phosphorus at 4mll-1 was the most effective treatment for increasing the morphological trail of plants and its chemical composition. Also, this treatment recorded the highest values of total and marketable tuber root yield, as well as the best tuber physical characters( fresh weight, length and diameter) and maximum concentration of nutritive values, i.e. N, P, K, protein and starch percentage , besides the root content of carotene. Conclusively, it could be concluded that the obtained results, it can be recommended that the treatment of 4 kg/ridge of chopped rice straw and foliar application of potassium and phosphorus at the concentration of 4 mll-1 for improving the properties of clay soil and to access the vigorous plant growth, maximum production with the best tuber quality of sweet potato.

Degradation of transgenic Bt-rice straw incorporated with two different paddy soils

Transgenic Bt-rice is rice that has been genetically modified to produce insecticidal proteins (Cry1Ab/Ac) within the plant. Rice straw is incorporated into paddy soils after harvest for fertilization or to improve the soil structure. The incorporation of straw from transgenic Bt-rice may pose risks to the paddy soil system. The decomposition of Bt-rice straw and degradation of Cry1Ab/Ac proteins from the straw were investigated under laboratory conditions. In addition, effects of the incorporation with chopped rice straw on microbial communities in differently textured paddy soils were studied. The results indicated that the incorporation of straw from transgenic Bt-rice might have a slight influence on soil respiration and CH4 emissions in two paddy soils, i.e. the Silt Loam soil and the Silty Clay soil. Differences were also observed in the cumulative emissions of CO2 between the two amended paddy soils in addition to the well-known increase in emissions of both CO2 and CH4 due to straw incorporation. The Cry1Ab/Ac proteins from straw of transgenic Bt-rice were degraded in paddy soils. The rate of decline in the concentration of Cry1Ab/Ac proteins was different in the two soils. After 29 d of incubation, 61% and 42% of initial Cry1Ab/Ac proteins were detected in the silt loam and silty clay, respectively. As a result of the presence of the rice straw, the abundance of bacteria, archaea, and total cells were increased in two soils. The numbers of bacteria and total cells were 6.4% and 11.5% higher in the silt loam amended with straw of Bt-rice than non-Bt-rice, respectively. The silty clay displayed a similar trend as the silt loam.

Urea based straw treatments for dairy cattle feeding management under farmers’ condition in Chitwan, Nepal

A study was conducted at Gitanagar VDC of Chitwan during May to August 2012, to find the effect of chopped and un-chopped rice straw in relation to with/ without treatment of urea (4%) on milk yield and its composition. Repeated Measure Design (RMD) was conducted in 8 cows and four treatments namely; T1 (un-chopped straw), T2 (chopped straw), T3 (un-chopped straw with urea solution @ 4%) and T4 (chopped straw with urea solution @ 4%) providing all four treatments to each cow at an interval of 15 days to match with the design. The samples of treatments were analyzed for CP, EE, CF, Moisture level, and total ash content. Urea treated rice straw consumption was significantly different (p&lt;0.05) among treatments. The average uptake of rice straw in T1, T2, T3 and T4 was found to be 3.39, 3.73, 3.81 and 3.9 kg/cow/day respectively. Similarly, milk yield from urea treated chopped rice straw was found significantly different (p&lt;0.01) among other treatments. The average milk yield in four treatments T1, T2, T3 and T4 was found to be 9.449, 9.697, 10.011 and 10.264 liters/cow/day. In milk composition, urea treated rice straw had positive impact on increment of protein and fat % which was significantly different (p&lt;0.01) and (p&lt;0.05) respectively. While SNF, lactose, density, solubility, freezing point were statistically similar (p&gt;0.05). Net income/cow was higher (Rs. 86.912) in T4 than other treatments.Journal of the Institute of Agriculture and Animal Science. Vol. 33-34, 2015, Page: 35-40

Performance of broiler chickens raised in boric acid amended chopped rice straw and paddy husk

A research study was carried out to evaluate the effects of boric acid amended chopped paddy straw and paddy husk on performance of broiler chickens. Total of 120, day-old, broiler chicks were randomly allocated into four treatment groups; CS= birds raised in chopped paddy straw, PH=birds raised in paddy husk, CS+H3BO3=birds raised in boric acid treated chopped paddy straw and PH+H3BO3=birds raised in boric acid treated paddy husk, with three replicates of ten birds each. The birds were fed with commercial diets. Boric acid was applied to the litter surface at the rate of 0.4 kg/9.3 m2 in weekly basis. Body weight gain and feed consumption were recorded weekly and feed conversion ratio (FCR) was calculated. On day 42, the carcass characteristics and the relative organ weights were measured. The birds raised on boric acid amended chopped straw and paddy husk had significantly increased (p<0.05) overall body weight gains, feed consumption, live body weight and carcass weight over the untreated groups. The FCR of birds kept on boric acid treated chopped straw was significantly (p<0.05) lower than untreated chopped straw and paddy husk. The dressing percentage was lowest (p<0.05) in the birds kept on untreated chopped straw than others. The birds raised on untreated chopped straw had higher (p<0.05) spleen weight and lower gizzard weight than those of untreated paddy husk regardless of boric acid amendment. Therefore, the boric acid amendment to chopped straw and paddy husk increases the growth performance of broiler chickens.

Influence of Moisture Content, Particle Size, and Binder Ratio on Quality and Economics of Rice Straw Briquettes

Rice straw as solid residues are biomass residue materials that are not optimally used by farmers in Punjab and potentially become environmental pollutant. A large amount of rice straw (17 million tons) is generated and left as much in combine harvested rice fields in Punjab, India. It is very difficult to manage such huge amount of rice straw thus, farmers resort to burning it which leads to greenhouse gas emissions like CO2 due to open field burning and loss of rich organic matter present in the soil. Further due to imposition of restrictions by the state government, the practice of burning rice straw has now become an offense. So farmers are looking for alternatives which are economically viable. Rice straw can be effectively used as bio energy as it has about the same heating value (15 kJ kg−1) as that of wood, half that of good quality coal and one third of oil. The operational conditions required to produce high-quality chopped rice straw briquettes have not been determined and this study determined the optimal moisture content, particle size, and binder ratio required to produce rice straw briquettes. The optimized conditions resulted in formation of high-density (1030.38–1159.22 kg m−3) briquettes with durability ranging from 71.9 to 92.3% with minimum power requirement for briquetting (36.60 kW), maximum calorific value of 15.61 MJ kg−1, and minimum ash content (16.34%).Total cost of making chopped rice straw briquettes was 0.041 USD per kg and 0.00281 USD per mega joule of energy. Cost of briquetting from chopped rice straw with 10 and 20% cotton stalks was 0.050 and 0.051 USD per kg, respectively, and 0.0033 USD per mega joule of energy. Also, the briquettes prepared from chopped rice straw with and without cotton stalk as a binder were economically viable.

Evaluating the effectiveness of agricultural mulches for reducing post-wildfire wind erosion

Abstract Post-wildfire soil erosion can be caused by water or aeolian processes, yet most erosion research has focused on predominantly water-driven erosion. This study investigates the effectiveness of three agricultural mulches, with and without a tackifier, on aeolian sediment transport processes. A wind tunnel was used to simulate post-wildfire wind erosion at three wind speeds (6, 11 and 18 m s−1). Shallow trays containing soil collected after a wildfire were treated with chopped rice, wheat or chopped wheat mulch; mulch treatments were also compounded with liquid treatments, tackifier to water ratios of 1:6, 1:3 and water. The mulch treatments were generally easily moved at all wind speeds with cover reductions greater than 90% at the highest wind speed. As expected, sediment loss was greatest for the bare soil treatment, ranging from 6.5 g m−2 at the lowest wind speed which increases to 6258 g m−2 at the highest wind speed. Adding wheat or chopped wheat mulch significantly reduced sediment loss by an order or magnitude (698 and 298 g m−2, respectively) at the highest wind speed. Adding chopped rice straw reduced sediment loss by a half to 3573 g m−2 at the highest wind speed, but the effect was not significant due to mobilization of the mulch. The most effective sediment loss mitigation was achieved with liquid tackifier treatments when applied to bare soil and when compounded with various mulch treatments, particularly at the highest wind speed. These results may aid management decisions when mitigating aeolian sediment transport after wildfires.

SOME PHYSICAL PROPERTIES OF RICE STRAW BRIQEUTTES

The main objective of the present study is to develop the fundamentals of a technology for energetic utilization of rice straw aimed at solving the problem of harmful storing and burning of rice straw in Egypt and preventing the smoke clouds caused by this and handling via the right way that is safe for both the environment and agriculture, producing a cheap, easily storable, and environmentally sound biofuel for rural areas in Egypt. Chopped rice straw was densified into briquettes using a laboratory model vertical hydraulic press at different formation pressures of (15, 32, 49 and 60 MPa), three temperature (room temperature (35oC), 75 and 100oC), three level of moisture content (6.53, 8.90 and 10.26% wb) and different holding time (10, 20 and 30 min). The results showed that the highest bulk density, compression ratio, durability and water resistance were 1337 kg/m3, 18, 95% and 107 min, respectively, at formation pressure of 60 MPa, temperature of 100oC, moisture content of 6.53% and holding time of 30 min. While, the minimum resiliency obtained was 6.53%. The CO, CO2 and NOx emissions values for rice straw briquettes decreased by 69, 54 and 37 %, respectively, of the emissions values CO, CO2 and NOx for chopped rice straw. The combustion efficiency was 99% and 70% for rice straw briquettes and chopped rice straw, respectively, and the burning time was about 74 and 15 min for rice straw briquettes and chopped rice straw, respectively.

The effects of fermentation and adsorption using lactic acid bacteria culture broth on the feed quality of rice straw

To improve the nutritional value and the palatability of air-dried rice straw, culture broth of the lactic acid bacteria community SFC-2 was used to examine the effects of two different treatments, fermentation and adsorption. Air-dried and chopped rice straw was treated with either fermentation for 30 d after adding 1.5 L nutrient solution (50 mL inocula L−1, 1.2×1012 CFU mL−1 inocula) kg−1 straw dry matter, or spraying a large amount of culture broth (1.5 L kg−1 straw dry matter, 1.5×1011 CFU mL−1 culture broth) on the straw and allowing it to adsorb for 30 min. The feed quality and aerobic stability of the resulting forage were examined. Both treatments improved the feed quality of rice straw, and adsorption was better than fermentation for preserving nutrients and improving digestibility, as evidenced by higher dry matter (DM) and crude protein (CP) concentrations, lower neutral detergent fiber (NDF), acid detergent fiber (ADF) and NH3-N concentrations, as well as higher lactic acid production and in vitro digestibility of DM (IVDMD). The aerobic stability of the adsorbed straw and the fermented straw was 392 and 480 h, respectively. After being exposed to air, chemical components and microbial community of the fermented straw were more stable than the adsorbed straw.

Effect of the addition of rice straw on microbial community in a sewage sludge digester

Rice straw was added to a sewage sludge digester and its effects on methane production, dewatering characteristics, and microbial communities in the digested sludge were examined by a continuous digestion experiment under mesophilic conditions (35 °C). Stable gas generation was monitored in all digestion experiments. Methane yield from raw sludge, chopped rice straw and softened rice straw were estimated to be 0.27, 0.18 and 0.26 NL/g total solids load, respectively. The capillary suction time of digested sludge was decreased by the addition of rice straw. Archaeal and bacterial communities in the sludge were elucidated by PCR-DGGE (polymerase chain reaction--denaturing gradient gel electrophoresis) targeting 16S rRNA genes. The Shannon index of DGGE profiles indicated that bacterial diversity increased with the addition of softened rice straw. DNA sequences of significant bands of the digested sludge were most closely related to Methanosaeta concilii (97.4% identity) and Methanoculleus bourgensis (100% identity). Meanwhile, those in the co-digested sludge with rice straw were most closely related to Methanosarcina barkeri (98.4% identity) and Methanoculleus bourgensis (99.3% identity). Although both Methanosaeta spp. and Methanosarcina spp. metabolize acetate to methane, Methanosarcina spp. have a competitive advantage at acetate concentrations of >70 mg/L. Results suggested that the quantity of acetate produced during rice straw degradation may change the archaeal community.

Effect of water regimes and organic sources of nutrients for higher productivity and nitrogen use efficiency of summer rice (Oryza sativa)

Field experiment was conducted at farmers’ field of old alluvial zone (Manikchak, Malda) of West Bengal, India during winters of 2007-2009 to study the effect of water management practices with different combinations of integrated plant nutrient supply including lathyrus green manure, vermicompost, poultry manure, chopped rice straw on productivity and nitrogen use efficiency of irrigated rice (Oryza sativa L.). Growth and yield attributes of rice, viz, effective tillers/m2, panicle length, number of grains/ panicle and 1000-grain weight were significantly highest in saturation from 15 to 35 days after transplanting followed by continuous ponding, among the water regimes and lathyrus green manuring 10 t ha-1, among the organic sources of nutrients. Similarly highest grain yield was recorded in saturation of top soil (0-40 cm) (4.26 and 4.32 tones ha-1) and lathyrus green manuring 10 t ha-1 (4.70 and 4.78 t ha-1), which was at par with the combined application of lathyrus green manuring 5 t ha-1 + vermicompost 2.5 t ha-1 + poultry manure 2.5 t ha-1 (4.66 and 4.75 t ha-1) and chopped rice straw 5 t ha-1 + lathyrus green manuring 5 t ha-1 (4.64 and 4.73 t ha-1). Irrespective of organic nutrients sources, saturation of top soil (0-40 cm) recorded highest net return (Rs 19613/- and 20281) and benefit:cost ratio (1.76 and 1.78) and the treatment lathyrus green manuring 10 t ha-1 (Rs 24592/- and 25484/- and 1.98 and 2.02) recorded among the organic nutrient management. Irrespective of water regimes, statistically highest N and K uptake were found in lathyrus green manuring 10 t ha-1 (115.59 to 118.39 kg ha-1) and (67.17 to 70.80 kg ha-1), respectively; however, highest P uptake was found in lathyrus green manuring 5 t ha-1 + vermicompost 2.5 t ha-1 + poultry manure 2.5 t ha-1 (49.24 to 50.57 kg ha-1). The nitrogen use efficiency indices such as agronomic efficiency, physiological efficiency, internal efficiency, recovery efficiency and partial factor productivity might be influenced when a part of nitrogen was supplied through organic sources. The highest water expanses efficiency was recorded in saturation of top soil (0 to 40 cm) (26.68 and 27.22 kg ha-1 mm-1), however, highest water saving (5.45 and 5.70%) was found in intermittent ponding of water. Key words: Lathyrus, nitrogen use efficiency, poultry manure, vermicompost, water expanses efficiency, water regimes.

Effects of physical form and urea treatment of rice straw on rumen fermentation, microbial protein synthesis and nutrient digestibility in dairy steers.

This study was designed to determine the effect of physical form and urea treatment of rice straw on rumen fermentation, microbial protein synthesis and nutrient digestibility. Four rumen-fistulated dairy steers were randomly assigned according to a 2 (2 factorial arrangement in a 4 (4 Latin square design to receive four dietary treatments. Factor A was roughage source: untreated rice straw (RS) and urea-treated (3%) rice straw (UTRS), and factor B was type of physical form of rice straw: long form rice straw (LFR) and chopped (4 cm) rice straw (CHR). The steers were offered the concentrate at 0.5% body weight (BW) /d and rice straw was fed ad libitum. DM intake and nutrient digestibility were increased (p<0.05) by urea treatment. Ruminal pH were decreased (p<0.05) in UTRS fed group, while ruminal ammonia nitrogen (NH3-N) and blood urea nitrogen (BUN) were increased (p<0.01) by urea treatment. Total volatile fatty acid (VFA) concentrations increased (p<0.01) when steers were fed UTRS. Furthermore, VFA concentrations were not altered by treatments (p>0.05), except propionic acid (C3) was increased (p<0.05) in UTRS fed group. Nitrogen (N) balance was affected by urea treatment (p<0.05). Microbial protein synthesis (MCP) synthesis were greater by UTRS and CHR group (p<0.05). The efficiency of microbial N synthesis was greater for UTRS than for RS (p<0.05). From these results, it can be concluded that using the long form combined with urea treatment of rice straw improved feed intake, digestibility, rumen fermentation and efficiency of microbial N synthesis in crossbred dairy steers.

Impact of Bagasse and Press Mud on Availability and Fixation Capacity of Phosphorus in an Inceptisol of North India

An incubation experiment was carried out at the Indian Agricultural Research Institute, New Delhi, India to explore the possibility of utilizing the organic residue i.e. press mud and bagasse byproducts generated from sugar industries to enhance the availability and reduction in fixation capacity of phosphorus (P). Three levels of organic residue (mixing press mud, bagasse and chopped rice straw in the ratio of 1:1:1) was applied at 0, 2.5 and 5 g/kg of soil with two levels of phosphorus i.e. 0 and 10 mg P2O5/kg of soil. Incorporation of organic residue enhanced the availability of P by 68 % over the control. Maximum P availability was observed after 11th month in maximum organic residue treatment. Phosphorus fixation capacity also decreased from 43 % (control) to 32 % (5 g/kg of soil). But the P fixation capacity increased with increasing level of P, due to easy availability of P for fixation. Use of the bagasse and press mud can be a good source of P mineralization in the already P fixed soil. It also reduced the storage problem in sugarcane industries across the India.

Rumen fermentation and performance of lactating dairy cows affected by physical forms and urea treatment of rice straw.

The aim of this study was to determine the effect of different physical forms and urea treatment of rice straw on feed intake, rumen fermentation, and milk production. Four, multiparous Holstein crossbred dairy cows in mid-lactation with initial body weight (BW) of 409±20 kg were randomly assigned according to a 4×4 Latin square design to receive four dietary treatments. The dietary treatments were as follows: untreated, long form rice straw (LRS), urea-treated (5%), long form rice straw (5% ULRS), urea-treated (2.5%), long form rice straw (2.5% ULRS) and urea-treated (2.5%), chopped (4 cm) rice straw (2.5% UCRS). Cows were fed with concentrate diets at a ratio of concentrate to milk yield of 1:2 and rice straw was fed ad libitum. The findings revealed significant improvements in total DM intake and digestibility by using long and short forms of urea-treated rice straw (p<0.05). Ruminal pH was not altered among all treatments (p>0.05), whereas ruminal NH3-N, BUN and MUN were found to be increased (p<0.01) by urea-treated rice straw as compared with untreated rice straw. Volatile fatty acids (VFAs) concentrations especially those of acetic acid were decreased (p<0.05) and those of propionic acid were increased (p<0.05), thus acetic acid:propionic acid was subsequently lowered (p<0.05) in cows fed with long or short forms of urea-treated rice straw. The 2.5% ULRS and 2.5% UCRS had greater microbial protein synthesis and was greatest when cows were fed with 5% ULRS. The urea-treated rice straw fed groups had increased milk yield (p<0.05), while lower feed cost and greater economic return was in the 2.5% ULRS and 2.5% UCRS (p<0.01). From these results, it could be concluded that 2.5% ULRS could replace 5% ULRS used as a roughage source to maintain feed intake, rumen fermentation, efficiency of microbial protein synthesis, milk production and economical return in mid-lactating dairy cows.