Nitrogen Content Of Straw Research Articles

Biochar as sustainable input for nodulation, yield and quality of mung bean

To reduce dependency on synthetic fertilizers in response to the escalating costs of fertilizers and environmental limitations, it is imperative to enhance crop productivity and soil fertility sustainably. This research was carried out at the Agricultural Research Farm of Abdul Wali Khan University in Mardan, Pakistan, with the objective of investigating the effects of biochar on the qualitative attributes of mung beans. The randomize complete block design (RCBD) was used for the experiment having four replication. The treatments comprised of four levels of biochar i.e. 0, 10, 20 and 30 t ha−1. Our results revealed that increasing biochar content caused an increase in yield components as well as attribute composition. The nodule density (17.8), pods plant−1 (27.3), grains pods−1 (11.4) and biological yield (6497 kg ha−1) produced best results under the application of 30 t ha−1 of biochar. Moreover, grain yield (1550 kg ha−1), grain nitrogen content (25.2 g kg−1) and straw nitrogen content (15.3 g kg−1) also resulted best under 30 t ha−1 biochar. While, 1000 grain weight (64 g) was recorded highest weight under 20 t ha−1. The quality attributes showed that the oil content (41.1%), as well as the saturated and unsaturated fatty acid contents (13.7%), were found to be the best under the application of 30 t ha−1. While, protein (23.37%) and linoleic acid (23.128%) content were the highest at 10 t ha−1of biochar. Moreover, the palmitic acid (6.1025%) and stearic acid (2.64%) content resulted higher under 20 t ha−1 of biochar. All the attributes showed positive response to either small level of biochar or a large level, but their response showed that biochar can be a factor that improves both yield and quality. The study therefore suggests that biochar should be applied to the soil to improve its fertility in regards of nutrient and increased organic matter.

Influence of Variety, Seedling Transplanting Age and Nitrogen Fertilizer Rates on Selected Chemical Composition of Rice Grains and Straws

The study was conducted under lowland ecological conditions at the Edozhigi and Badeggi National Cereal Research Institute (NCRI) farms in the Guinea savannah region of southern Nigeria during the 2015 and 2016 growing seasons. The objective was to determine the effect of seedling transplanting age and nitrogen fertilizer rates on nutrient content of two rice varieties. The trial was laid out in a split-split plot arrangement fitted into randomized complete block design (RBCD) and replicated three times. The treatments for the trial consisted of two rice varieties as the main factor (FARO 44 and FARO 52), the sub plot factor consisted of four seedling transplanting ages (7, 14, 21 and 28) and the sub-sub plot factor consisted of five inorganic N fertilizer rates (0, 60, 120, 180 and 240 kg N/ha). Rice grains and straw after harvest were analyzed for N, P, K, Fe and Zn content. The result of the rice grain and straw nutrient content revealed a significant effect of location on rice grain nitrogen and zinc content. Rice planted at Edozhigi gave significantly higher nitrogen and zinc content in rice grains in 2015 and 2016 planting seasons. Nitrogen fertilizer application had significant effect on rice grain nitrogen content in 2016 planting season. The result showed a significant (p<0.05) effect of variety on Zn content of rice grains. Rice variety Faro 44 produced significantly higher rice grain zinc content of 0.334 and 0.297 ppm during both planting seasons. Significantly (p<0.05) rice variety Faro 44 had higher rice straw nitrogen content of 0.172 and 0.165% in 2015 and 2016 planting seasons respectively. In conclusion, the application of 240 kg N/ha to 14 and 28 days old of Faro 44 rice variety revealed more nutrient content in rice grain and straw.

Application of potassium nitrate and salicylic acid improves grain yield and related traits by delaying leaf senescence in Gpc-B1 carrying advanced wheat genotypes.

Grain protein content (GPC) is an important quality trait that effectively modulates end-use quality and nutritional characteristics of wheat flour-based food products. The Gpc-B1 gene is responsible for the higher protein content in wheat grain. In addition to higher GPC, the Gpc-B1 is also generally associated with reduced grain filling period which eventually causes the yield penalty in wheat. The main aim of the present study was to evaluate the effect of foliar application of potassium nitrate (PN) and salicylic acid (SA) on the physiological characteristics of a set of twelve genotypes, including nine isogenic wheat lines carrying the Gpc-B1 gene and three elite wheat varieties with no Gpc-B1 gene, grown at wheat experimental area of the Department of Plant Breeding and Genetics, PAU, Punjab, India. The PN application significantly increased the number of grains per spike (GPS) by 6.42 grains, number of days to maturity (DTM) by 1.03 days, 1000-grain weight (TGW) by 1.97g and yield per plot (YPP) by 0.2 kg/plot. As a result of PN spray, the flag leaf chlorophyll content was significantly enhanced by 2.35 CCI at anthesis stage and by 1.96 CCI at 10 days after anthesis in all the tested genotypes. Furthermore, the PN application also significantly increased the flag leaf nitrogen content by an average of 0.52% at booting stage and by 0.35% at both anthesis and 10 days after anthesis in all the evaluated genotypes. In addition, the yellow peduncle colour at 30 days after anthesis was also increased by 19.08% while the straw nitrogen content was improved by 0.17% in all the genotypes. The preliminary experiment conducted using SA demonstrated a significant increase in DTM and other yield component traits. The DTM increased by an average of 2.31 days, GPS enhanced by approximately 3.17 grains, TGW improved by 1.13g, and YPP increased by 0.21 kg/plot. The foliar application of PN and SA had no significant effect on GPC itself. The findings of the present study suggests that applications of PN and SA can effectively mitigate the yield penalty associated with Gpc-B1 gene by extending grain filling period in the wheat.

RESPONSE OF SOYBEAN (GlycinemaxL. Merrill) PRODUCTIVITY TO BIOFERTILIZER INOCULANTS COMBINED WITH ORGANIC FERTILIZERUNDER SANDY SOIL CONDITIONS

One of the most important food sources for humans is the soybean crop because it is an important source ofprotein and oil, which makes it important to improve its productivity under stress conditions, especially in sandy lands.Therefore, the study aimed to improve soybean productivity by using biological fertilizers in the presence of organicfertilizer and low concentration of mineral fertilizer under new sandy soil conditions.The experiment was carried out intwo summer seasons of 2020 and 2021 at the Ismailia Research Station, Ismailia Governorate. The used inoculates inthe experiment were,an identified Streptomyces strain,Bacillus megatherium, (SEWRI) and Bradyrhizobiumjaponicum(Okaden) as,biofertilizer agents.Activated dose of N-fertilizer was used in seven different treatments. Results showedthat Bradyrhizobia+Bacillus+actinomycetes+20 kg nitrogen fertilizer/fed was effective in the presence of organicfertilizer compared to organic fertilizer-free soil or un-inoculated+70 kg N/fed. Bradyrhizobia+ Bacillus+Actino+20 kgN/fed (T14) was the most effective treatment in the presence of organic fertilizer compared to organic fertilizer-free soilor uninoc.+70 kg N/fed. Promising expected yields of each of seeds and straw (Ton/fed) of soybean plants cultivatedunder different fertilizers and biofertilizers conditions expected was clear from increasing the yield seed up to1.8400Ton/fed in the presence of organic fertilizer (T14) compared to 1.4565 when soybean was cultivated in theabsence of organic fertilizer (T01). This could be supported by the amounts of NPK, N-percentage, and protein content,numbers of branches and pods and dehydrogenase activity in soil. Significant differences between the straw yield in thepresence and absences of organic fertilizer as well as biofertilizers were recorded. Organic fertilizer applicationrecorded the highest significant increases in nodulation status, growth and straw nitrogen content as well as harvestparameter of soybean compared with those un-received organic fertilizer

Investigation of fifteen popular and widely grown Indian rice varieties for variations in straw fodder traits and grain-straw relationships

Fifteen 15 popular rice cultivars were investigated over two years for grain yield (GY) and straw yield (SY), harvest indices (HI), straw nitrogen content (N), neutral (NDF) and acid (ADF) detergent fiber, acid detergent lignin (ADL), Silica, in vitro organic matter digestibility (IVOMD) and metabolizable energy (ME) content. Except for ADL (P = 0.06) highly significant (P < 0.0001) differences were observed for all traits. The observed cultivar-depend variations were substantial with GY varying by 1.8-fold and SY by 2.3-fold and HI by 1.6-fold. Important straw fodder quality traits such straw N varied by 1.5-fold and the cultivar with the highest IVOMD differed from the poorest one by 6.1 percentage points. With the exceptions of N and ADL, year had a significant effect on traits. Broad sense heritability (H2) for SY and IVOMD were substantial (>0.73) and intermediate (>0.49) for GY, NDF, ADF and ME and poor (<0.17) for Silica, N and ADL.Possible trade-offs between traits were investigated. GY and SY were unrelated (P = 0.52). Nitrogen content of rice straw tended (P = 0.08) to be inversely related with GY but not with SY (P = 0.89). NDF content was unrelated to GY (P = 0.52) but was significantly (P = 0.01) positively correlated with SY. The reverse was observed for ADF, which was significantly (P = 0.02) positively correlated with GY but unrelated to SY (P = 0.48). ADL was not correlated (P = 0.79) with GY but was positively associated (P = 0.01) with SY. Silica content was also unrelated (P = 0.17) to GY but was inversely (P = 0.03) associated with SY. IVOMD and GY were inversely associated (P = 0.07) as was ME and GY (P = 0.09. IVOMD tended (P = 0.1) to also inversely related to SY but ME and SY were not related (P = 0.24). To summarize, considerable cultivars-dependent variations in food and fodder traits exist among released cultivars, though key positive straw quality traits could inversely (P < 0.10) associated with GY. Straw storage influenced straw quality, though an unexpected one since quality tended to improve. Key straw quality traits at harvest and after storage were still significantly correlated but the correlation coefficients could fall substantially below 1.

Effect of potassium (K+) on growth, yield components and macronutrient accumulation in Wheat crop

Abstract Plant growth, nutrient uptake and yield can be sustained by the application of potassium fertilization. A pot experiment was conducted to study the effect of macronutrients accumulation of wheat about different potassium rates.The results revealed that the effect of different potassium levels on the growth and grain yield of wheat was significant. The application of potassium at 100% increased the most of the growth, yield components and accumulation of nutrients in wheat crop from 20−50% as compared to (control) the plots receiving no potassium application. In comparison to control, potassium application at 75% also significantly increased growth and yield components from 8−40%, however, potassium application of 50 and 25% increased the growth and yield components by 4−20%. As compared to plots receiving no potassium, application of potassium resulted 3−6% higher nitrogen content in grain and 2−11% higher nitrogen content in straw. While, potassium application increased the potassium contents by 50−154% in grain and 70-140% contents of potassium in straw as compared to control plots. However, in comparison to plots without potassium nutrition, application of potassium fertilization improved phosphorus contents by 2−10% in grain and 3-50% in straw of wheat crop. Among potassium levels of 25%, 50%, 75% and 100% were significant indicating that potassium at the rate of 100% was an optimum level for obtaining maximum grain yields in wheat crop. This study concluded that application of potassium nutrition increased the all growth, yield comonents and accumumation of nitrogen, phosphorus and potassium contents in grain and straw of wheat crop. Keywords: Macronutrients; Potassium; Wheat http://dx.doi.org/10.19045/bspab.2018.700183

The effect of sulphur and nitrogen supply on the growth and nutrient content of spring wheat (Triticum aestivum L.)

Sulphur is an essential element for plants. Decreasing sulphur deposition from the air, and the use of more concentrated phosphate fertilizers, which contain no sulphur, has led to reports of sulphur deficiencies for wheat. Sulphur deficiency significantly affects yield and also the quality of wheat. The pot experiment was set up on calcareous chernozem soil at Látókép, Hungary, test plant was spring wheat (Triticum aestivum L). Seven treatments were used where nitrogen and sulphur were supplied as soil fertilizers in increasing rates (NS1, NS2, NS3) and in foliar fertilizer as well (NS1+fol., NS2+fol., NS3+fol.). Plant aboveground biomass production was determined in samples taken in the stages of development BBCH 29-30, 51-59, 61-69, 89. The nitrogen and sulphur content of straw and grain were measured. N/S ratios of grain and straw were calculated. The weights of grain were ranging between 8.6–16.1 g/pot. NS2 and NS2+fol. treatments produced the highest values. Foliar fertilizer had no further effect on grain. Analysing the values of the straw, it was observed that tendencies were similar to values of grain. The NS2 treatment produced the highest weight of straw and the NS3 rate already decreased that amount. The obtained results show the unfavourable effect of excessively high rate applied in NS3 treatment. The supplementary foliar fertilizer had no significant influence on the weight of straw. Both N and S-uptake of plant was very intensive at the stem elongation stage, then the N and S-content of plant continuously decreased in time in all treatments. The N-content of grain ranged between 2.215–2.838%.&#x0D; The N-content of grain slightly increased with increasing of nitrogen doses. In the higher doses (NS2, NS3) foliar fertilization slightly increased the nitrogen content of grain, although this effect was not statistically proved. The N-content of straw varied from 0.361 to 0.605%. The growing dose of soil fertilizer also considerably increased the nitrogen content of straw. Foliar fertilization further increased the nitrogen content of straw. The S-content of grain ranged between 0.174–0.266%. The lowest fertilizer dose (NS1) significantly increased the sulphur content of grain. The further increasing fertilizer doses (NS2, NS3) did not cause additional enhance in sulphur content of grain.&#x0D; The foliar fertilizer also did not change the sulphur value of plant. The increasing amount of soil fertilizer and the supplementary foliar fertilizer had no effect on the sulphur content of straw. The treatments influenced the N/S ratios of grain and straw. On the basis of experimental results it can be concluded that the examined nitrogen and sulphur containing soil fertilizer had positive effect on the growth and yield of spring wheat grown on the calcareous chernozem soil. The soil fertilizer application enhanced the grain nitrogen and sulphur content. The highest rate of fertilizer (600 kg ha-1) proved to have decreasing effect on the yield. The sulphur and nitrogen containing foliar fertilizer did not have significant effect on the yield parameters but slightly increased the nitrogen content of plant.

Yield and Nitrogen Use Efficiency of Locally Improved Rice Varieties in Rice Based Tidal Flooded Ecosystem of Bangladesh

An on farm field experiment was conducted to evaluate locally improved aman rice varieties in terms of nitrogen use efficiency and grain yield in southern region of Bangladesh. The treatments were: i. deep placement of urea (UDP) before panicle initiation stage and ii. farmers’ practice (FP/control). The locally popular rice varieties were used as planting materials. Higher panicles m-2 and grains panicle-1 was obtained from UDP application compared to FP. Nitrogen fertilization increases grain and straw nitrogen content significantly. Application of urea before panicle initiation stage gave considerable higher grain yield in all cultivated varieties. Cultivated aman varieties produced 2.0 to 2.5 t ha-1 grain without application of N fertilizer. But, cultivated local variety Razashail, Kutiagoni, Sadachikon, Sadapajam, Lalmota and Sadamota gave 3.0 to 3.5 t ha-1 grain in tidal prone areas with UDP. Hence, application of urea gave yield advantage by 0.5 to 1.0 t ha-1. The highest internal, agronomic, recovery and physiological efficiency; nitrogen harvest and grain yield efficiency index was obtained from Kutiagoni, Lalpayka, Sadachikon, Sadapajam, Moulata and Lalmota. Based on the yield and nitrogen fertilizer use efficiency, it could be concluded that UDP before panicle initiation stage is an effective option of urea application for rice cultivation in tidal prone areas.Bangladesh Agron. J. 2016 19(2): 39-49

고추밭 고랑 볏짚피복에 의한 양분유출 특성

농경지에 작물재배를 위한 양분재료의 과다한 투여는 주변 수계로의 양분유출을 증가시킬 수 있다. 고추재배시 사용되는 양분재료는 화학비료, 우분퇴비, 돈분퇴비 등이 대표적이다. 볏짚은 벼 재배의 부산물로 밭 농사에서 잡초발생 억제, 토양수분 보존, 유기물 재료로 널리 사용된다. 본 연구는 노지 고추 재배에서 밭 고랑을 볏짚으로 피복할 때 강우로 발생하는 표면 유출수에 의한 양분유출 특성을 파악하기 위해 수행하였다. 시험구는 양분재료를 기준으로 하여 화학비료, 우분퇴비, 돈분퇴비로 구분하였고 양분투입량은 토양검정 시비량에 준하여 처리하였다. 각각의 시험구는 화학비료 또는 우분퇴비, 돈분퇴비를 시용한 후 볏짚으로 덮은 경우(피복 처리구)와 덮지 않은 경우(무피복구)로 구분하였다. 화학비료 처리구와 우분퇴비 처리구의 볏짚 고랑 피복 처리는 무피복구 보다 T-N (총질소)의 유출이 각각 <TEX>$1.4kg\;ha^{-1}$</TEX>, <TEX>$2.1kg\;ha^{-1}$</TEX> 감소하였다. 반면에 화학비료 처리구와 우분퇴비 처리구, 돈분퇴비 처리구의 볏짚고랑 피복 처리는 무피복구 보다 T-P (총인)의 유출이 각각 <TEX>$2.1kg\;ha^{-1}$</TEX>, <TEX>$2.1kg\;ha^{-1}$</TEX>, <TEX>$0.2kg\;ha^{-1}$</TEX> 증가하였다. 볏짚은 질소 0.4 %, 인산을 0.3 % 함유하고 있고 증류수에 볏짚을 담근 후 3주일 내에 인산 성분이 유출되므로 T-P의 유출은 고랑을 피복한 볏짚에서 기원한 것으로 추정된다. 무피복구에 비하여 고랑 볏짚 피복구는 잡초발생이 줄었다. 그러나 붉은 고추의 수확량은 무피복구와 볏짚피복구 간에 유의한 차이를 나타내지 않았다. 결론적으로, 고추밭 고랑을 볏짚으로 과다하게 피복하면 T-P의 유출을 유발할 수 있으므로 고랑을 피복하는데 적정한 볏짚량을 산정하기 위한 추가적인 연구가 필요하다고 판단되었다. Excessive application of nutrient supplement on the upland soil may increase the amount of discharge to surrounding water systems. The chemical fertilizer (CF), cow manure compost (CMC), and pig manure compost (PMC) are used as a nutrient supplement for cultivation of red pepper. Rice straws are widely used as a soil covering material in order to reduce weed occurrence, to protect soil moisture, and to supply organic matter in upland soil. This study was conducted to evaluate the furrow covering effect with rice straw on nutrient discharge in upland soil used for red pepper cultivation. The experimental plots of nutrient supplement were consisted of CF, CMC, and PMC and the amount of nutrient application were as recommended amount after soil test for red pepper cultivation. Each nutrient supplement treatment plot has no furrow covering (CFC) as a control and furrow covering with rice straw (FCS), respectively. Furrow covering with rice straw (FCS) of CF treatment and CMC treatment reduced the amount of T-N(total nitrogen) discharge by <TEX>$1.4kg\;ha^{-1}$</TEX>, <TEX>$2.1kg\;ha^{-1}$</TEX>, respectively, compared to control. While the amount of T-P(total phosphorus) discharge of the furrow covering with rice straw of CF, CMC, and PMC increased by <TEX>$2.1kg\;ha^{-1}$</TEX>, <TEX>$2.1kg\;ha^{-1}$</TEX>, and <TEX>$0.2kg\;ha^{-1}$</TEX>, respectively, compared to control. The phosphorus and nitrogen content of straw were 0.4 % and 0.3 % respectively. In addition, in three week the phosphorus was eluted from the straw which soaked in distilled water. Thus, it was assumed that T-P discharging originated from rice straw which applied as a furrow covering material. The furrow covering with rice straw reduced weed occurrence compared to control. But production of fresh red pepper was not influenced significantly by furrow covering with rice straw. In conclusion, excessive furrow covering with rice straw could induce T-P discharge from upland soil used for red pepper cultivation. Further studies are needed to evaluate the appropriate amount of rice straw as a furrow covering material.

Effects of changes in straw chemical properties and alkaline soils on bacterial communities engaged in straw decomposition at different temperatures.

Differences in the composition of a bacterial community engaged in decomposing wheat straw in a fluvo-aquic soil at 15 °C, 25 °C, and 35 °C were identified using barcode pyrosequencing. Functional carbon groups in the decomposing wheat straw were evaluated by 13C-NMR (nuclear magnetic resonance). Actinobacteria and Firmicutes were more abundant, whereas Alphaproteobacteria and Bacteroidetes were less abundant, at higher temperatures during the later stages of decomposition. Differences in the chemical properties of straw accounted for 19.3% of the variation in the community composition, whereas soil properties accounted for more (24.0%) and temperature, for less (7.4%). Carbon content of the soil microbial biomass and nitrogen content of straw were significantly correlated with the abundance of Alphaproteobacteria, Actinobacteria, and Bacteroidetes. The chemical properties of straw, especially the NCH/OCH3, alkyl O-C-O, and O-alkyl functional groups, exercised a significant effect on the composition of the bacterial community at different temperatures during decomposition—results that extend our understanding of bacterial communities associated with the decomposition of straw in agro-ecosystems and of the effects of temperature and chemical properties of the decomposing straw and soil on such communities.

The effect of a sandy soil amendment with municipal solid waste (MSW) compost on nitrogen uptake efficiency by plants

The purpose of this work was to determine the influence of municipal solid waste (MSW) compost application on soil properties, nitrogen availability to plants and its uptake efficiency. The paper deals with results of a three-year field experiment where two different MSW composts were non-recurrently applied to sandy soil at rates of 18, 36 and 72tha−1 (dry mass). Plots without fertilisation as well as plots fertilised each year with mineral forms of NPK were the controls, and spring triticale was cultivated in a monoculture on all plots as a test plant. Soil properties, plant yield and nitrogen content in grain and straw were determined at harvest, and on this basis the applied nitrogen uptake efficiency was calculated. During the first year, only the plots with the highest dose of the better-quality compost had yields similar to the plots fertilised with mineral NPK. Following the years of the experiment, all the plots treated with compost had distinctly lower yields than the plots fertilised with mineral NPK. That decrease was accompanied by a decrease in the nitrogen content in straw and grain, in spite of the fact that the soil material indicated a similar content of total nitrogen to those fertilised with NPK. This indicates that organic matter brought into the soil with MSW compost was intensively mineralised, releasing a considerable amount of nitrogen. However, the plant response indicated a shortage of the plant-available forms of this element. The efficiency of compost-originated nitrogen uptake by plants was very low, at less than 7% of the applied nitrogen. This indicates that plants can take up only a limited amount of nitrogen released from the compost, while considerable amounts are emitted into the atmosphere.

Environmental effects on associations among nitrogen use efficiency traits in wheat

Nitrogen use efficiency parameters of twelve bread wheat cultivars were studied in nine environments comprised of three nitrogen applications tested over three years. An environment-by-trait association biplot and a trait-association by environment biplot were applied to understand environmental effects on these traits and relationships among them. The following trait associations were relatively stable across environments: negative associations of straw nitrogen content vs. nitrogen remobilization efficiency, straw nitrogen content vs. nitrogen harvest index and a positive association of nitrogen remobilization efficiency vs. nitrogen harvest index. The selection of genotypes with a high nitrogen harvest index and nitrogen remobilization efficiency could be used in the development of cultivars with desired nitrogen use efficiency. A low straw nitrogen content can also be used as a reliable and cost-effective indicator in the selection of genotypes with high nitrogen use efficiency.

Comparison of an aerial-based system and an on the ground continuous measuring device to predict yield of winter wheat

The objective of the research was to compare an aerial image with optical data of an on the ground platform device measuring continuously while driving through the field. For this latter, a Cropscan, Inc. multi-spectral radiometer was used to automatically take a measurement every 1–1.5 m. Field images of the normalized difference vegetation index (NDVI) of both devices were compared in their capability estimating yield variability in a wheat field. An experimental field with three seeding densities and five nitrogen application rates was investigated. Every treatment had four repetitions, resulting in 60 plots of 12 m × 16 m. At harvest, yield variables of the plots (grain and straw yield (t/ha), dry matter content in grain and straw (t/ha), nitrogen in grain and straw (kg[N]/ha) and protein content (%) in grain) were collected to relate to the images of both systems. The NDVI of both measurement systems was well related to applied nitrogen in the field: correlation coefficients were 0.78 and 0.85 for the aerial-based and the ground-based system, respectively. There was a high similarity (correlation coefficient of 0.94) between NDVI measurements of both systems. NDVI was also well related to yield variables at harvest. The NDVI of the ground system was better related to yield variables at harvest compared to NDVI of the aerial system. Best correlation coefficient found for both systems was with nitrogen in grain: 0.84 and 0.91 for the aerial-based and the ground-based system, respectively. NDVI images were more related to yield quality. Grain yield already reached its optimum in the field, while grain quality still increased with increasing nitrogen application rate. For the ground system, the average estimation errors, when using linear regression analysis, were smaller than 10% for all yield variables except for estimated straw yield and estimated nitrogen content in straw. For the aerial system, also estimated total nitrogen content exceeded the 10% error percentage. Besides the higher accuracy in the estimation of yields variables, the ground system had the advantage of being cheaper and that the data were immediately available.

The effect of urease enzyme on treatment time and the nutritive value of straw treated with ammonia as urea

Three experiments were conducted with hammer-milled (10-mm screen) rice and barley straw treated with urea solution, alone or with urease enzyme. In Experiment 1 rice straw was treated with 10, 20, 40, 60 or 80 g urea dissolved in 1 l of water/kg straw, alone or with pure urease, in sealed polythene bags for 1, 2, 6, 14 or 21 days. In Experiment 2 rice straw was treated with 40 or 80 g urea/kg straw and ground soya bean as the source of urease, for 0, 2, 4 or 6 days. Both experiments showed that urea significantly ( P < 0.001) increased organic matter digestibility in vitro and the nitrogen content of the straw. The addition of urease reduced the treatment time to 2–4 days. Ground soya bean appeared to be a satisfactory source of urease for treated straw. In Experiment 3 barley straw was treated with 0, 40 or 80 g urea/kg straw, as in Experiment 1, for 0, 2, 4, 6 or 14 days. Half the treated material was further subjected to a spray treatment with 1 M acetic acid at the time of opening of the bags. Acetic acid treatment significantly ( P < 0.001) depressed organic matter digestibility in vitro of treated straw, but retained 10–15% of the added urea which otherwise would have been lost to the atmosphere as ammonia. It appeared that the urea treatment was inefficient as a means of increasing the nitrogen content of straw. However, the process improved the digestibility of straw and, in the presence of urease, the treatment process could be reduced to 2–4 days.

The effect of prolonged storage on the digestibility and nitrogen content of ammonia-treated barley straw

Barley straw in a 10-t stack was treated with anhydrous ammonia (40 kg t −1 straw dry matter). Four bales, two buried in the stack and two with one face exposed, were sampled before treatment, at 54 days (1 day after the stack was first opened) and at regular intervals thereafter for a further 12 days. The total nitrogen content of the straw increased from the 6.7 g kg −1 straw dry matter present before treatment to 20.7 g kg −1 at day 54. Ammonia nitrogen contributed 7.4 g and non-ammonia nitrogen 6.6 g of this increase. There was a rapid loss of ammonia on opening the stack and this continued for the first week; thereafter ammonia was lost at a much slower rate. In all, 39% of the ammonia nitrogen present 1 day after opening was lost by the end of the sampling period. This loss accounted for the 18% reduction in total nitrogen recorded over the same period. Loss of nitrogen did not affect the digestibility of treated straw as determined by the nylon bag method using sheep. Digestibility, whether expressed as loss of dry matter or as digestibility of cellulose, remained constant throughout. Added water-insoluble nitrogen appeared to be more readily available than that initially present in untreated straw. The position of bales within the stack did not affect results significantly.

Alkali treatment and fermentation of straw for animal feed

AbstractThe feed value of annual ryegrass straw was improved by treatment with various concentrations of NaOH or NH3 followed by fermentation of the treated straw with a mixed culture of Cellulomonas sp. and Alcaligenes faecalis. Laboratory feeding trials with voles showed that NaOH or NH3 treatment considerably increased the feed efficiency of straw, but apparently gave a poorly palatable product. Fermentation tended to decrease the in vitro rumen digestibility (IVRD) of alkali‐treated straw. The fermentations were carried out aerobically on a semisolid straw matrix having 11–86% moisture. Treatment by both NaOH and NH3 increased the IVRD of straw. NH3 also increased the nitrogen content in straw. The optimum condition for alkaline treatment of the straw was 4–6% NaOH for 1 hr or with 3% NH3 for four weeks at room temperature. A minimum of 63% moisture was needed for significant fermentation of the straw. The combined effects of NaOH treatment and fermentation more than doubled crude protein, doubled crude fat, and increased IVRD by 75%. The NH3 plus fermentation treatment tripled crude protein, doubled crude fat, and increased IVRD by 60%. Acetic acid was the main volatile fatty acid in the fermented straw.