• Authors:
    • Li, G.
    • Luo, C.
    • Wang, X.
    • Niu, Y.
    • Gao, C.
    • Nan, Z.
    • Shen, Y.
    • Yang, J.
  • Source: Acta Prataculturae Sinica
  • Volume: 19
  • Issue: 1
  • Year: 2010
  • Summary: The effects of conventional tillage (t), conventional tillage with stubble retention (ts), no-tillage (nt), and no-tillage with stubble retention (nts) treatment on crop yield, soil total nitrogen and carbon, total organic carbon, oxidizible organic carbon, and carbon pool management index (CPMI) were investigated within a maize-wheat-soy rotation system in the western Loess Plateau. Total crop yield for ten harvests during the years 2001 to 2007 under ts and nts treatments increased by 3.63 and 1.62 g/kg compared with conventional tillage, but decreased by 2.48 g/kg on the nt treatment. Total nitrogen contents under nts treatment were 15.4%, 30.2% and 16.2% higher than t, ts and nt treatments. Total carbon under nts treatment was significantly increased by 2.04 g/kg and total organic carbon were 2.50, 1.56 and 1.70 g/kg higher than under t, ts and nt treatment, respectively. Easily oxidized organic carbon under nts was 2.13 g/kg higher than under t treatment. TN/TC decreased by 12.75%, 15.97%, 6.87% and 24.16% under t, ts, nt and nts treatments. The CPMI under ts, nt and nts were 12.6%, 20.1% and 46.6% higher than under t, both stubble retention and no-till were beneficial to increasing the soil organic carbon content and improving the quality of the carbon pool.
  • Authors:
    • Zhang, X.
    • Shi, F.
    • Li, B.
    • Xue, Y.
    • Yang, Z.
  • Source: Journal of Henan Agricultural Sciences
  • Issue: 10
  • Year: 2010
  • Summary: By using field monitoring methods, the village, the water consumption of winter wheat grown Zhangcun town of Huixian county, Henan province were determined. Water consumption can reach 216.3-345.2 mm at the yield level of 4 500-6 000 kg/ha. The water consumption percentage constitution of different growing period was 25.9%-36.9% between seeding and reviving stages, 22.0%-31.1% between reviving and heading stages, and 31.9%-52.2% between heading and maturation. The variation was great among different years. When the yield level of corn was 6 750-7 500 kg/ha, water consumption 299.6-462 mm which account for 81.3%-97.4% of precipitation during the period of the year. The water consumption percentage constitution of different growing period was 17.1%-17.3% between seeding and jointing stages, 34.5%-39.1% between jointing and trumpet stages, and 43.6%-48.4% between trumpet and maturation stages. For both wheat and corn, the water consumption density increased dramatically after jointing stage. The jointing and seed filling stages were two important periods for wheat water consumption. The trumpet stage was important for corn. In the dry-land hilly areas of middle and north Henan province at the current situation, natural precipitation can generally meet the water demand of autumn grain crops, while for summer grain crops, it is inadequate. So the emphases of water-saving irrigation should be on the summer grain crops.
  • Authors:
    • Balesdent, J.
    • Munoz, C.
    • Vidal, I.
    • Zagal, E.
  • Source: Proceedings of the 19th World Congress of Soil Science: Soil solutions for a changing world
  • Year: 2010
  • Summary: Sustainable agriculture should maintain soil organic carbon to prevent soil degradation and erosion, but soil C management still requires basic data on soil C dynamics under many climates, soil types and land uses. We applied a simple field method for the measurement of soil carbon dynamics, based on the natural 13C labelling technique of carbon inputs. The method implies the addition of locally produced maize material into the soil with C3 crops, in a simple, light and cost-effective design, and the kinetic analysis of soil 13C/ 12C. In Chile the approach was applied on a nine years fertility experiment with no till conditions sustaining a wheat-oat rotation, and followed thereafter for 5 years. The experimental site is located in the Andes pre-mountain (36degrees55′S, 71degrees53′O). The soil is of volcanic origin (medial, amorphic, mesic, Typic Haploxerands) and the crop rotation wheat-oat. The labeling technique showed that a very low amount (about 1 t ha -1) was incorporated to the soil (new C) during the time-period of the experiment (4 years). The ratio of remaining C/ added C after 4 years was very low (0.03) suggesting that the high carbon content of the soil can therefore be considered as due to a large amount of passive carbon, or to ancient carbon inputs, that have saturated the sorption capacity.
  • Authors:
    • Naeem, M.
    • Khan, F.
    • Ahmad, W.
  • Source: Soil and Environment
  • Volume: 29
  • Issue: 1
  • Year: 2010
  • Summary: This study was undertaken as a part of soil fertility management of eroded soils in NWFP, Pakistan. The study was started in summer 2006 and continued for four consecutive crop seasons till winter 2007, in District Swabi, NWFP, Pakistan. Soil fertility status of the experimental site was determined before the start of the experiment. The experiment was laid out in a factorial split plot design using two factors viz cropping patterns and fertilizer treatments. The cropping patterns included maize-wheat-maize rotation, maize-lentil-maize rotation and maize-wheat+lentil intercrop-maize rotation and these were kept in main plots whereas the fertilizer treatments included control, 50% NP, 100% NPK and 20 t ha -1 farmyard manure integrated with 50% N and 100% PK as mineral fertilizers which were placed in sub plots. Fertilizers were applied for four seasons continuously. At the end of winter 2007, soil samples from two depths (0-20 cm and 20-40 cm) were collected from each plot and analyzed for microbial biomass carbon (MBC) at day 3, day 6 and day 10 incubation periods, total nitrogen (TN), microbial biomass nitrogen (MBN), and mineralizable nitrogen (MN). Results showed significant improvement in organic fertility of soil with fertilizer addition and cropping patterns. Combined application of organic and inorganic fertilizers (20 t ha -1 farmyard manure integrated with 50% N and 100% PK) showed 55, 25, 18 and 61% increase in total N, MBN, MN, and MBC after 10 days incubation period over the control, respectively, in the surface soil whilst 100% NPK showed 44, 15, 6 and 45% improvement over the control treatment for the same parameters in surface soil. Data further showed 43, 23, 19 and 60% increase in the corresponding microbial parameters in combined organic and inorganic fertilizer treatment over the control treatment in sub soil whilst 100% NPK showed 39, 20, 10 and 54% increase in TN, MBN, MN and MBC over the control in sub soil. The cropping patterns having cereal-legume rotation also improved organic soil fertility and showed 27 and 13% more total N and MBC after 10 days incubation period over the cereal-cereal rotation respectively and the improvement in MBN and MN in cereal-legume rotation over cereal-cereal rotation was non significant in surface soil. In the sub-surface soil cereal-legume rotation improved TN, MBN, MN and MBC by 9, 6, 8 and 28% over the cereal-cereal rotation. It was concluded that there is sufficient potential to improve soil organic fertility in Pirsabak soil series, the restoration of which on sustained basis would require at least 50% N from the organic sources. Moreover legumes must be included in the traditional cereal-cereal cropping pattern to further improve the N input and organic fertility of these soils.
  • Authors:
    • Bagwan, N.
  • Source: International Journal of Plant Protection
  • Volume: 3
  • Issue: 2
  • Year: 2010
  • Summary: Crop root exudates of 20 crops like groundnut, soybean, pigeonpea, green gram, black gram, chickpea, pea, cowpea, mustard, cotton, castor, sunflower, safflower, sesamum, sorghum, pearl millet, maize, wheat, onion, and garlic were used in this study. Large variations of inhibitory effect of root exudates on S. rolfsii were observed. Low concentrations of root exudates (5% and 10%) had no effect on inhibition of mycelial growth and germination of sclerotia while, at high concentration (20%) inhibited the mycelial growth and germination of sclerotia. Mycelial growth, dry mycelium weight and sclerotial germination were recorded lowest in root exudates of sunflower, maize, pearl millet, sorghum, safflower, garlic, and onion. Mycelial growth, dry mycelium weight and sclerotial germination was recorded highest in root exudates of soybean, groundnut, green gram, black gram, pigeonpea, chickpea, pea and cowpea. It was observed that the root exudates of maize, sunflower and pearl millet showed a highest percentage of inhibition of mycelial growth and sclerotial germination. Another interesting of thing was observed that root exudates of groundnut, soybean and pea stimulate the mycelial growth and germination of sclerotia as compared to control. The results of this study suggested that the intercropping or crop rotation of safflower, maize, pearl millet, sorghum, sunflower, garlic, and onion with groundnut may be useful for the management of stem rot of groundnut and also for reduction of soil population of S. rolfsii in groundnut field. Similarly intercropping or crop rotation of soybean, green gram, black gram, chickpea, pea and cowpea with groundnut should be avoided. Based on these findings, it is hypothesized that root exudates of some crops contain antifungal compounds, while other stimulate the growth of fungal pathogens. Cultivation of safflower, maize, pearl millet and sorghum with groundnut could lead to a reduction in the occurrence of stem rot disease, especially when chemical control is not effective and economically costly. However, further investigation is necessary for isolation and identification of antifungal compounds in root exudates related to host-pathogen interaction.
  • Authors:
    • Yaduraju, N. T.
    • Das, T. K.
    • Tadesse, B.
  • Source: Weed Biology and Management
  • Volume: 10
  • Issue: 3
  • Year: 2010
  • Summary: Parthenium is widely distributed across the uncropped areas of the tropics. It has slowly encroached into many crops and causes considerable yield loss. It heavily infests sorghum, which is widely cultivated by the resource-poor farmers in Africa and Asia. Its interference and management in sorghum in these cropping systems is not well understood. Therefore, this experiment was undertaken to determine the appropriate parthenium management techniques to use in sorghum crops. All the studied weeds, in combination with parthenium, offered greater competition to sorghum than parthenium alone. Similarly, under a composite stand of weeds, parthenium was inferior in competitiveness to the other weeds until 60 days after sowing (DAS); by 90 DAS, it could accumulate a higher dry weight due to its consistent growth. A pre-emergence treatment of atrazine (0.75 kg ha -1) with wheat straw mulch (5.0 t ha -1) brought about a consistent and significant reduction in the parthenium growth and, consequently, increased the sorghum yield by 90.8%. Cowpea intercropping with and without pendimethalin (1.0 kg ha -1) as a pre-emergence treatment could not control parthenium between 0 and 60 DAS, but could reduce the parthenium growth during the later period of 60-90 DAS, which resulted in a significant increase in sorghum growth. These intercropping treatments increased the sorghum grain yield by 156.2% and 142.4%, respectively, over the unweeded control and by 18.5% and 12.1%, respectively, over the weed-free control. These treatments also promoted a higher uptake of N, P, and K by the sorghum crop. Thus, cowpea intercropping was the most effective method for parthenium management vis-a-vis sorghum yield improvement, followed by cowpea intercropping with pendimethalin and then by atrazine as a pre-emergence treatment with wheat straw mulch.
  • Authors:
    • Singer, J.
    • Moorman, T.
    • Cambardella, C.
  • Source: Nutrient Cycling in Agroecosystems
  • Volume: 87
  • Issue: 3
  • Year: 2010
  • Summary: Coupling winter small grain cover crops (CC) with manure (M) application may increase retention of manure nitrogen (N) in corn ( Zea mays L.), -soybean [ Glycine max (L.) Merr], cropping systems. The objective of this research was to quantify soil N changes after application of liquid swine M ( Sus scrofa L.) at target N rates of 112, 224, and 336 kg N ha -1 with and without a CC. A winter rye ( Secale cereale L.)-oat ( Avena sativa L.) CC was established prior to fall M injection. Surface soil (0-20 cm) inorganic N concentrations were quantified every week for up to 6 weeks after M application in 2005 and 2006. Soil profile (0-120 cm in 5, 20-cm depth increments) inorganic N, total N, total organic carbon and bulk density were quantified for each depth increment in the fall before M application and before the CC was killed the following spring. Surface soil inorganic N on the day of application averaged 318 mg N kg -1soil in 2005 and 186 mg N kg -1soil in 2006 and stabilized at 150 mg N kg -1soil in both years by mid-November. Surface soil NO 3-N concentrations in the M band were more than 30 times higher in the fall of 2005 than in 2006. The CC reduced surface soil NO 3-N concentrations after manure application by 32% and 67% in mid- November 2005 and 2006, respectively. Manure applied at 224 kg N ha -1 without a CC had significantly more soil profile inorganic-N (480 kg N ha -1) in the spring after M application than manured soils with a CC for the 112 (298 kg N ha -1) and 224 (281 kg N ha -1) N rates, and equivalent inorganic N to the 336 (433 kg N ha -1) N rate. These results quantify the potential for cover crops to enhance manure N retention and reduce N leaching potential in farming systems utilizing manure.
  • Authors:
    • Conte, O.
    • Levien, R.
    • Trein, C.
    • Cepik, C.
  • Source: REVISTA BRASILEIRA DE ENGENHARIA AGRICOLA E AMBIENTAL
  • Volume: 14
  • Issue: 5
  • Year: 2010
  • Summary: No tillage implies keeping the soil surface covered with crops or crop residues, which might influence planter performance. Using fixed shanks as furrow openers to place fertiliser is an alternative to minimize compaction, as it mobilizes the soil in the sowing line. The aim of this research was to evaluate the effect of different amounts of winter cover crop residues evenly distributed on the soil, the effect of the shanks working depth and quantity of planter lines on power demand, cross sectional furrow area and total volume of soil mobilized in the lines and corresponding wheel slippage in distrophic red Argisol. During winter, black oats and black oats plus turnip were used as cover crops before maize and beans, respectively. Increasing the working depth showed an increase in power demand, as measured directly at the shanks (three lines for maize and five for beans). There was also an effect of residue, increasing power demand on the shanks, but only measurable with the planter operating with three lines in maize sowing. Soil mobilization in the sowing lines was influenced by the amount of residues, the working depths of shank and the quantity of planter lines. Wheel slippage was higher with larger amounts of soil cover residues and when power demand was higher.
  • Authors:
    • Vieira, F. C. B.
    • Flores, J. P. C.
    • Anghinoni, I.
    • Souza, E. D.
    • Costa, S. E. V. G. A.
    • Martins, A. P.
    • Ferreira, E. V. O.
  • Source: Soil & Tillage Research
  • Volume: 109
  • Issue: 1
  • Year: 2010
  • Summary: The distribution of phosphorus in the soil profile as a function of soil tillage, fertilizer management system and cultivation time is strongly related to root distribution. As the dynamics of this process are not well understood, long-term experiments are useful to clarify the cumulative effect through time. The study evaluated an 18-year-old experiment carried out on Rhodic Paleudult soil, located in Rio Grande do Sul state - Brazil, with cover crops (black oat and vetch) in the winter and corn in the summer. In the 0- to 20-cm layer, the amounts of clay, silt and sand were 22, 14, and 64 g kg -1, respectively. This layer had a mean slope of 3%. The mean local annual rainfall is 1440 mm. The climate is subtropical with a warm humid summer (Cfa), according to the Koeppen classification. The treatments consisted of three soil managements (conventional tillage, no tillage and strip tillage) and three application modes (broadcast, row and strip) for triple superphosphate and potassium chloride fertilizers. Data for phosphorus and root distribution in the soil from the 1989/90, 1999/00 and 2006/07 growing seasons were used. Phosphorus stratification occurred through time, irrespective of soil and fertilizer management, mainly in the 0- to 5-cm layer. The tillage and fertilization systems promoted significant differences in the Pi and Pt fractions up to a depth of 20 cm. For the Po fraction, significant differences were found only in the 0- to 5- and 15- to 20-cm layers. Inorganic phosphorus accumulated in the fertilized zone (0-10 cm), with higher intensity in the no-tillage system under row fertilization with values around 150 mg dm -3. Root distribution presented a strong positive relationship with phosphorus distribution, exhibiting redistribution in the soil profile through time. This redistribution was accompanied by increases in organic phosphorus and total organic carbon content. Corn grain yield was not affected by long-term tillage systems.
  • Authors:
    • Conte, O.
    • Trein, C. R.
    • Levien, R.
    • Debiasi, H.
    • Kamimura, K. M.
  • Source: PESQUISA AGROPECUARIA BRASILEIRA
  • Volume: 45
  • Issue: 6
  • Year: 2010
  • Summary: The objective of this work was to evaluate the effect of soil winter covers and soil mechanical loosening on soybean and corn yield, in no-tillage system. Two experiments were carried out in Rio Grande do Sul state, Brazil, in a compacted Argissolo Vermelho (Haplic Acrisol), in the 2005/2006 and 2006/2007 crop seasons. The first experiment was carried out in a complete block design, with a split plot arrangement. The treatments were two theoretical working depths of a driller chisel-type furrow opener (0.06 and 0.12 m, split plot), and three soil winter covers (main plot): fallow, black oat ( Avena strigosa), and black oat+common vetch ( Vicia sativa). In 2006, the soil cover black oat+common vetch was replaced by oilseed radish ( Raphanus sativus). In the second experiment, in a complete block design, the soil was chiseled and treatments consisted of black oat or oilseed radish as winter cover crops. Cover crops reduced soil superficial (0-0,06 m) compaction compared to fallow and, in the 2005/2006-crop season, under low water availability, provided higher soybean and corn yields. In the 2006/2007-crop season, when water availability was higher, the same did not happen. Increasing working depths of the chisel-type furrow opener did not affect soybean or corn yields. Soil chiseling reduced soybean and corn yields in comparison to the continuous no-tillage system.