• Authors:
    • Jyoti, K.
    • Tarunvir, S.
  • Source: Agricultural Situation in India
  • Volume: 66
  • Issue: 7
  • Year: 2009
  • Summary: This study examines the cost and returns of dry land maize in the Jammu District of Jammu and Kashir state in India; the resource use efficiency and estimates the extent of instability in cropped area, yield and net returns.
  • Authors:
    • Ranamukhaarachchi, S.
    • Thongsaga, K.
  • Source: Asia-Pacific Journal of Rural Development
  • Volume: 19
  • Issue: 1
  • Year: 2009
  • Summary: Water stress is unpredictable in rain-fed agriculture, and regularly affects maize production in Thailand. This study was conducted to determine the effect of 10-day dry period occurring during critical growth stages on growth and yield of maize, and to simulate and compare the performance using CERES-Maize model in DSSAT version 4.0.2.0 using concurrent weather data. Two popular maize hybrids, namely Suwan 4452 and Pacific 224, were subjected to four 10-day dry periods [viz. 36-45 days from seeding (DFS), 46-55 DFS, 56-65 DFS, and 66-75 DFS] as treatments together with a control grown with regular irrigation in a split plot design with four replicates. The experiment was conducted during the longest dry period, from December 2006 to April 2007, under controlled irrigation. Soil moisture content at 0-15 cm and 15-30 cm depths reached near the lower limit of readily available water (RAW) in six days, after the cessation of irrigation, which declined to near permanent wilting point (PWP), but did not reach PWP during the 10-day period. Leaf area index (LAI) (ranged from 4.3 to 4.6), plant height (ranged from 2.2 to 2.4 m) and biomass (ranged from 6.8 to 7.6 t/ha) at silking were not significantly affected by the 10-day suspension of irrigation, but various differences were observed in the plant height: Suwan 4452 was taller than Pacific 224. Number of grains per ear, 100-grain weight, grain yield and the harvest index remained unaffected due to the 10-day suspension of irrigation, but were significantly greater in Pacific 224 than Suwan 4452. CERES-Maize model showed excellent results in predicting time to silking, LAI and biomass at silking, 100-grain weight, grain yield and the harvest index. However, some deviations were found in Suwan variety for LAI and 100-grain weight, and of Pacific 224 in the time to silking. Comparisons showed that simulations were very much close, except for the cases noted. The model simulated responses similar to the actual values in this study.
  • Authors:
    • Wilhelm, W. W.
    • Varvel, G. E.
    • Wienhold, B. J.
  • Source: Communications in Soil Science and Plant Analysis
  • Volume: 40
  • Issue: 13-14
  • Year: 2009
  • Summary: Mineralization contributes significantly to agronomic nitrogen (N) budgets and is difficult to accurately predict. Models for predicting N-mineralization contributions are needed, and development of these models will require field-based data. In situ mineralization methods are intended to quantify N mineralization under ambient environmental conditions. This study was conducted to compare soil moisture and temperature in intact soil cores contained in cylinders to those in adjacent bulk soil, compare the effect of two resin-bag techniques on water content of soil within cylinders, and assess the effect of installation duration on inorganic N retention by resins. The study was conducted at a dryland conventionally tilled corn ( Zea mays L.) site and an irrigated no-tillage corn site in eastern Nebraska. Soil in cylinders was slightly wetter (<0.05 g g -1) and warmer (<1C) than adjacent soil. Soil water content was <80% water-filled pore space (WFPS) at all sampling times and differed little between the two resin-bag techniques. Greater soil water content and temperature conditions (though small) observed during most of the study period likely enhanced N mineralization within the cylinder compared to N mineralization in adjacent bulk soil, but the magnitude is likely much less than core-to-core variation normally observed in a field. Installing cylinders for more than 60 days resulted in loss of inorganic N from resins. Care is needed during installation to ensure that compaction of soil below the cylinder does not impede water movement through the intact soil core. The in situ method utilizing intact soil cores and resin bags replaced at 28- to 40-day intervals is a viable method for measuring N mineralization.
  • Authors:
    • Huang, W.
    • Xiao, L.
    • Wang, H.
    • Pan, G.
    • Zheng, Y.
  • Source: Guizhou Agricultural Sciences
  • Issue: 1
  • Year: 2009
  • Summary: The intercropping and interplanting between maize and potato were studied in Guizhou, China, to investigate the application rates and cultivation measures for balance high yield in the dry land with middle and lower yield. The maximum profit of the dry land with middle and lower yield in Nayong county with middle and high elevation was 1336.55 yuan/667 m 2 under the application ratio of 1:0.53:0.83 of N:P 2O:K 2O, and the comprehensive utilization rate of N, P 2O and K 2O was 33.52, 17.51 and 44.71%. The maximum profit of the dry land with middle and lower yield in Weining county with high elevation was 1349.09 yuan/667 m 2 under the application ratio of 1:0.69:1.10 of N:P 2O:K 2O, and the comprehensive utilization rate of N, P 2O and K 2O was 29.68, 10.58 and 26.80%, respectively.
  • Authors:
    • Li, S.
    • Chen, X.
    • Xu, H.
    • Liu, Y.
    • Zhu, L.
  • Source: Scientia Agricultura Sinica
  • Volume: 42
  • Issue: 12
  • Year: 2009
  • Summary: Objective: According to the investigations on soil temperature dynamics in the spring maize growing season, a field experiment was conducted to examine the effects of different maize culturing practices on soil temperature dynamics and soil accumulated temperature (>10degreesC) in Loess Plateau. Hence it has a certain reference value for understanding the influence of different culturing practices on spring maize growth. Method: Shendan10 was used as the test crop. Three field water management practices, including supplementary irrigation (SI), rain-fed (RF) and plastic film mulching (FM), were adopted in spring maize fields in 2007. Maize straw mulching (SM) was added in 2008. The experiment was arranged in a randomized complete block design. Result: The results showed that the plastic film had a significant warming effect while the maize straw mulching had a cooling effect. During the course of crop growing season, soil accumulated temperature (>10degreesC) had the peak at vegetative growth stages (VE-R1), followed by growth stages (R1-R6), and reached the lowest value at seedling stage (PT-VE). Moreover, soil accumulated temperature was different in different culturing practices during the course of crop growing stages. Soil accumulated temperature was lower in the PT-VE period in plastic film mulching treatment, VE-R1 period in supplementary irrigation treatment and R1-R6 period in rain-fed treatment. The response of plastic film mulching soil temperature was most sensitive to air temperature, and the response of straw mulching soil temperature was most insensitive to the air temperature. The crop grain yield was significantly improved under both the supplementary irrigation and the film mulching treatments compared to the rain-fed treatment, with the increases of 30.0% and 18.1% in 2007, and 25.7% and 29.7% in 2008, respectively. Conclusion: It is concluded that different maize culturing practices in the Loess Plateau not only affect the soil temperature dynamic changes, but also affect the maize growth and the utilization of the soil heat resources.
  • Authors:
    • Veiga, M.
    • Pelissari, A.
    • Moraes, A.
    • Balbinot Junior, A.
    • Dieckow, J.
    • Nesi, C.
  • Source: Revista de Ciencias Agroveterinarias
  • Volume: 8
  • Issue: 1
  • Year: 2009
  • Summary: Animal trampling is one of the major causes of soil compaction in areas subjected to integrated crop-livestock system. The objective of this work was to evaluate the effect of winter annual pasture grazing, in crop-livestock system, and other winter soil uses on soil compaction. The experiment was carried out from May 2006 to February 2007 at three sites of the North Plateau of Santa Catarina State, Brazil. Five winter treatments were investigated on each site: (1) intercropping with black oat+ryegrass+vetch+arrow leaf clover without grazing and nitrogen fertilization (multicropping cover); (2) the same intercropping, with grazing and 100 kg ha -1 of nitrogen, (grazing with N); (3) the same intercropping, with grazing and without nitrogen fertilization (grazing without N); (4) oil seed radish, without grazing and nitrogen fertilization (oil seed radish); and (5) natural vegetation, without grazing and nitrogen fertilization (fallow). Undisturbed cores were collected from the layers 2 to 7 cm and 10 to 15 cm, at three times: experiments implantation (May 2006), at maize sowing in succession of winter soil use (November 2006) and close to maize physiological maturity (February 2007). Soil total porosity, bulk density and soil resistance to penetration were evaluated in these samples. According to the environmental and management conditions, as well as the time of experimentation, the livestock presence in winter pastures, winter cover crops and fallow did not affect the variables related to soil compaction.
  • Authors:
    • Smith, R. F.
    • Boyd, N. S.
    • Brennan, E. B.
    • Foster, P.
  • Source: Agronomy Journal
  • Volume: 101
  • Issue: 4
  • Year: 2009
  • Summary: Winter cover crops can add soil organic matter, improve nutrient cycling, and suppress weeds in organic vegetable systems. A 2-yr study was conducted on organic farms in Salinas and Hollister, CA, to evaluate the effect of seeding rate (SR) and planting arrangement on cover crop density, ground cover, and cover crop and weed dry matter (DM) with a mixed cover crop. The mix contained legumes (35% Vicia faba L., bell bean; 15% Vicia dasycarpa Ten., woolypod vetch; 15% Vicia benghalensis L., purple vetch; and 25% Pisum sativum L., pea) and 10% oat ( Avena sativa L.) by seed weight. Three SRs (112, 224, and 336 kg ha -1) and two planting arrangements (one-way versus grid pattern) were evaluated. Planting arrangement had no effect on the variables measured. When weeds were abundant, weed DM declined linearly with increasing SR from approximately 300 kg ha -1 at the low SR to
  • Authors:
    • Mazurana, M.
    • Debiasi, H.
    • Trein, C.
    • Levien, R.
    • Conte, O.
  • Source: Ciencia Rural
  • Volume: 39
  • Issue: 4
  • Year: 2009
  • Summary: This study evaluates the effect of machine traffic, soil mobilization, soil cover by crop residues and water supply on corn under no tillage on a Paleudult. Machine traffic intensity, working depth of driller shank furrow opener for fertilizer deposition and amount of residues covering the soil surface, with and without irrigation, were evaluated. The experimental design used was split plot, with 36 plots being 18 with irrigation and 18 without irrigation. The treatments were quantities (0, 2, 4, 5, 6 and 8 Mg ha -1) of black oats ( Avena strigosa) and vetch ( Vicia sativa) residues, two driller shank depths for fertilizer deposition (6 and 12 cm) and traffic machine conditions (tractor and combine) in a triple factorial design with three replicates. Corn was sowed in 12/10/2005, using 62.000 seeds per hectare. A basal dressing of NPK 5-20-20 was applied at a rate of 400 kg ha -1. Two top dressing nitrogen applications were performed, totalizing 180 kg ha -1 of N. Corn grain yield, plant population and root dry matter were evaluated. Corn yield and plant population were influenced by presence or absence of irrigation. None of the above parameters were modified by working depth of driller shank furrow opener for fertilizer deposition. Wheel traffic conditions affected corn yield and plant population.
  • Authors:
    • Eastridge, M. L.
    • Dick, R. P.
    • Barker, D. J.
    • Sulc, R. M.
    • Fae, G. S.
    • Lorenz, N.
  • Source: Agronomy Journal
  • Volume: 101
  • Issue: 5
  • Year: 2009
  • Summary: The benefits of cover crops within crop rotations are well documented, but information is limited on using cover crops for forage within midwestern United States cropping systems, especially under no-tillage management. Our objective was to evaluate plant, animal, and soil responses when integrating winter cover crop forages into no-till corn ( Zea mays L.) silage production. Three cover crop treatments were established no-till after corn silage in September 2006 and 2007 at Columbus, OH: annual ryegrass ( Lolium multiflorum L.), a mixture of winter rye ( Secale cereale L.) and oat ( Avena sativa L.), and no cover crop. Total forage yield over autumn and spring seasons was 38 to 73% greater ( P≤0.05) for oat+winter rye than for annual ryegrass. Soil penetration resistance (SPR) in May 2007 was 7 to 15% greater ( P≤0.10) in the grazed cover crops than in the nongrazed no cover crop treatment; however, subsequent silage corn yield did not differ among treatments, averaging 10.4 Mg ha -1 in August 2007. Compared with the no cover crop treatment, cover crops had three- to fivefold greater root yield, threefold greater soil microbial biomass (MB) in spring 2008, and 23% more particulate organic carbon (POC) concentrations in the 0- to 15-cm soil depth. Integration of forage cover crops into no-till corn silage production in Ohio can provide supplemental forage for animal feed without detrimental effects on subsequent corn silage productivity, with the added benefit of increasing labile soil C.
  • Authors:
    • Albuquerque, J. A.
    • Reichert, J. M.
    • Reinert, D. J.
    • Genro Junior, S. A.
  • Source: CIENCIA RURAL
  • Volume: 39
  • Issue: 1
  • Year: 2009
  • Summary: A study was conducted to evaluate the effects of crop succession and rotation on the crop yields and physical properties of an oxisol (clayey Haplortox) under no-tillage system, in Rio Grande do Sul State, Brazil. The treatments included four cropping sequences, used from 1998 to 2001: (1) succession wheat/soyabean; (2) rotation corn/oat/corn + Cajanus cajan/wheat/soyabean/wheat; (3) rotation Cajanus cajan/wheat/soyabean/wheat/soybean/oat; and (4) rotation Crotalaria juncea/wheat/soyabean/oat/corn/wheat. In October 2000 and 2001, soil samples were collected to determine the physical properties, and in all years, crop yields were measured. The oxisol under no-tillage had a high degree of compaction with the greater soil bulk density and lower macroporosity than the critical limit for clay texture. The largest limitations were observed below the layer of 0-0.03 m, because in the uppermost layer, soil mobilization by successive operations of fertilizer application and sowing increased soil porosity and reduced soil density. Thus, greater volume of pores was observed between soil saturation and field capacity, responsible for soil aeration, and between field capacity and wilting point, responsible for storage of plant available water. The use of cover crops once every three years was not efficient to reduce soil compaction. The yield of the subsequent crops was positively influenced in the rotation with Crotalaria juncea, while the other cropping systems did not differ from crop succession.