Effect of tillage practices on the fate of hard seeds of subterranean clover in a ley farming system

1985 ◽  
Vol 25 (3) ◽  
pp. 568 ◽  
Author(s):  
GB Taylor

In a rotation of 1 year pasture/l year crop, a subterranean clover (Trifolium subterraneum cv. Daliak) pasture was either left untilled or subjected to minimum or conventional tillage. One set of tillage treatments was imposed in each ofthree crop years while another set of treatments was imposed in only the first crop year. Regenerating clover plants were prevented from setting seed. In the first crop, 44% of the clover seeds were buried below 2 cm of soil by minimum tillage; this proportion was 65% in the conventional tillage treatment. In the first pasture regeneration year, seedling densities were highest in the no-tillage treatment. Conversely, there were more residual seeds in the tilled treatments and, in the second and third pasture regeneration years, this led to higher seedling densities than in the no-tillage treatment. The effects of tillage were more marked in the conventional than in the minimum-tillage treatment. Clover establishment was improved by repeat tillage operations which returned some of the buried seeds closer to the soil surface. Although more seedlings overall were obtained from the no-tillage treatment, the disadvantage of fewer seedlings in the tilled treatments was offset by the spread of seedling establishment over a number of pasture years. This spread, which would be more marked with harder-seeded cultivars, could be desirable in environments in which clover seed production is unreliable.


1990 ◽  
Vol 4 (3) ◽  
pp. 534-538 ◽  
Author(s):  
Adrian J. Enache ◽  
Richard D. Ilnicki

Subterranean clover as a living mulch was evaluated for weed control and its effect on field corn silage and grain yield in 1986 to 1988. Treatments included combinations of subterranean clover living mulch, rye dead mulch, and no mulch with three superimposed tillage practices (conventional, minimum, and no-tillage). Results indicated that subterranean clover living mulch effectively controlled ivyleaf morningglory. Little control of fall panicum was obtained in 1986; however, living mulch combinations effectively controlled fall panicum in 1987 and 1988. Weed biomass was reduced significantly by all living mulch combinations, but all other combinations resulted in higher weed biomass than living mulch. Corn silage and grain yields from the no-tillage plus living mulch treatment were comparable to or higher than those obtained with the conventional tillage plus no mulch treatment.



2015 ◽  
Vol 39 (1) ◽  
pp. 268-278 ◽  
Author(s):  
Elói Panachuki ◽  
Ildegardis Bertol ◽  
Teodorico Alves Sobrinho ◽  
Paulo Tarso Sanches de Oliveira ◽  
Dulce Buchala Bicca Rodrigues

Surface roughness of the soil is formed by mechanical tillage and is also influenced by the kind and amount of plant residue, among other factors. Its persistence over time mainly depends on the fundamental characteristics of rain and soil type. However, few studies have been developed to evaluate these factors in Latossolos (Oxisols). In this study, we evaluated the effect of soil tillage and of amounts of plant residue on surface roughness of an Oxisol under simulated rain. Treatments consisted of the combination of the tillage systems of no-tillage (NT), conventional tillage (CT), and minimum tillage (MT) with rates of plant residue of 0, 1, and 2 Mg ha-1 of oats (Avena strigosa Schreb) and 0, 3, and 6 Mg ha-1 of maize (Zea mays L.). Seven simulated rains were applied on each experimental plot, with intensity of 60±2 mm h-1 and duration of 1 h at weekly intervals. The values of the random roughness index ranged from 2.94 to 17.71 mm in oats, and from 5.91 to 20.37 mm in maize, showing that CT and MT are effective in increasing soil surface roughness. It was seen that soil tillage operations carried out with the chisel plow and the leveling disk harrow are more effective in increasing soil roughness than those carried out with the heavy disk harrow and leveling disk harrow. The roughness index of the soil surface decreases exponentially with the increase in the rainfall volume applied under conditions of no tillage without soil cover, conventional tillage, and minimum tillage. The oat and maize crop residue present on the soil surface is effective in maintaining the roughness of the soil surface under no-tillage.



Author(s):  
Nguyễn Trung Hải ◽  
Trần Thanh Đức ◽  
Vi Thị Linh

Nghiên cứu này nhằm đánh giá tác động của các biện pháp làm đất và mật độ trồng khác nhau đến quá trình sinh trưởng, phát triển, năng suất và hiệu quả kinh tế của giống ngô lai HQ2000 trên đất cát nội đồng trong vụ Đông Xuân năm 2018-2019 tại Thừa Thiên Huế. Thí nghiệm thứ nhất gồm 3 công thức gồm làm đất truyền thống, làm đất tối thiểu và không làm đất trong đó thí nghiệm thứ hai gồm 4 công thức với mật độ gieo trồng lần lượt là 47.058, 53.333, 61.538 và 66.666 cây/ha. Kết quả thí nghiệm cho thấy: Thời gian hoàn thành các giai đoạn sinh trưởng và phát triển ở các biện pháp làm đất tối thiểu có xu hướng ngắn hơn các công thức làm đất truyền thống; chiều cao cây cuối cùng dao động từ 154 đến 175cm, số lá dao động từ 16 đến 18 lá, diện tích lá đóng bắp có xu hướng giảm ở các công thức làm đất tối thiểu trong khi các yếu tố khác như chiều cao đóng bắp, chiều dài bắp, đường kính bắp và đường kính lóng gốc ở các công thức thí nghiệm dao động tương đối ít. Năng suất lý thuyết dao động từ 61 đến 72 tạ/ha, năng suất thực thu đạt cao nhất là 59,8 tạ/ha ở công thức không làm đất. Đối với biện pháp canh tác truyền thống, năng suất đạt cao nhất ở mật độ 18,5 kg hạt giống/ha (63,4 tạ/ha). Ở các công thức thí nghiệm, lợi nhuận đạt cao nhất ở công thức không làm đất và ở mật độ trồng là 18,5 kg hạt giống/ha, tương đương 61.538 cây/ha.  ABSTRACT This study aims to evaluate the impact of different tillage methods and planting densities on the growth, development, grain yield and economic efficiency of hybrid maize HQ2000 on sandy soil in the 2018-2019 Winter-Spring season in Thua Thien Hue province. The first trial consisted of three treatments including conventional tillage, limited tillage and no tillage; the second trial consisted of four treatments with planting density of 47.058, 53.333, 61.538 và 66.666 plants/ha, respectively. Experimental results showed that: The completed time of the growth and development stages at the minimum tillage methods was shorter than conventional tillage treatments; final plant height varied from 154 to 175cm, the number of leaves ranged from 16 to 18 leaves, the leaf area at ​​corn position decreased in minimum tillage treatments while other factors such as ear height, ear length, ear diameter and stalk diameter at prop root position fluctuated slightly. Potential grain yield varied from 6.1 to 7.2 tons/ha, the highest actual grain yield was 5.98 tons/ha in the no-tillage treatment. For conventional tillage, the highest grain yield was at 18.5 kg seed/ha treatment (6.34 tons/ha). In the experimental treatments, the highest profit was achieved in the no-tillage treatment and in planting density of 18.5 kg seed/ha, equivalent 61,538 plants/ha.      



1988 ◽  
Vol 2 (3) ◽  
pp. 323-326 ◽  
Author(s):  
Kurt D. Thelen ◽  
James J. Kells ◽  
Donald Penner

Field trials were conducted in 1985 and 1986 to determine the effect of incorporation on volatilization of clomazone from soil. Volatilization was detected up to 2 weeks after surface-applied or soil-incorporated treatments of clomazone at 1.1 kg ai/ha. The amount of volatilization detected was greatest following rainfall and varied between years. More clomazone volatilized after surface application than after incorporation, regardless of the climatic conditions present. Clomazone volatilization detected was in the order of no-tillage > minimum tillage > conventional tillage.



1997 ◽  
Vol 48 (5) ◽  
pp. 683 ◽  
Author(s):  
B. S. Dear ◽  
P. S. Cocks

Subterranean clover seedling numbers and growth in swards containing 1 of 5 perennial pasture species [phalaris (Phalaris aquatica) cv. Sirolan, cocksfoot (Dactylis glomerata) cv. Currie, lucerne (Medicago sativa) cv. Aquarius, wallaby grass (Danthonia richardsonii) cv. Taranna, and lovegrass (Eragrostis curvula) cv. Consol] were compared with those in typical annual pastures and pure clover swards in the wheatbelt of eastern Australia. Presence of a perennial species or the volunteer annual grass (Eragrostis cilianensis) increased the rate of drying of the soil surface (0–5 cm) after late February and May rain, compared with subterranean clover swards. Perennials differed in the rate they dried the soil surface, with the more summer-active lucerne and consul lovegrass drying the profile more rapidly than phalaris. The amount of water in the surface 5 cm, 6 days after the rainfall event on 27–28 February, was strongly negatively correlated (r = –0·75, P < 0·01) with the amount of green perennial biomass, but not related to standing dead material or surface residues. Where perennials were present, a smaller proportion (2–4%) of the clover seed pool produced seedlings in response to late summer rain, compared with pure clover swards (18%). A higher proportion of the seed pool produced seedlings (19–36%) following rain in late autumn but there was no difference between species. The more summer-active perennials (cocksfoot, danthonia, and lucerne) markedly depressed the survival of emerged clover seedlings following both germinations. Of the seedlings that emerged in early March, the proportion remaining by 29 March was 57% in phalaris, 21% in lucerne, 13% in danthonia, and 1% in cocksfoot, compared with a 78% increase in seedlings in pure subterranean clover swards. By 15 May, all perennials had <2 clover seedlings/m2 surviving, compared with 37 in the annual pasture and 964 plants/m2 in pure subterranean clover. Following the May germination, the highest proportion of emerged seedlings surviving until 29 May was in the phalaris swards (40%) and least in the cocksfoot and danthonia swards (2–4%). Presence of a perennial or annual grass decreased (P < 0·05) relative water content of clover seedlings on 15 March from 74% in pure clover swards, to 48% in annual pasture, 34% in phalaris, and 29% in lucerne swards. Clover seedlings growing in pure subterranean swards on 15 March (17 days after germinating rain) were 4 times larger than those in lucerne and twice as large as those in either phalaris or annual pasture. Seed size did not differ between treatments, but available mineral soil nitrogen was significantly higher (P < 0·001) in pure subterranean clover swards (32 mg N/g) compared with perennials (3–13 mg N/g). Strategies such as heavy grazing in late summer to reduce green biomass of the perennials or sowing the perennials at lower densities may reduce the adverse effects that perennials have on subterranean clover seedlings in these drier environments.



1995 ◽  
Vol 46 (3) ◽  
pp. 553 ◽  
Author(s):  
RJ Stirzaker ◽  
I White

Excessive cultivation in many horticultural areas results in soil structural decline and poor utilization of water and nutrients. There are no reliable techniques for growing irrigated vegetables without cultivation. This work explores the hypothesis that a winter legume cover-crop can overcome the soil limitations of no-tillage and provide an alternative to excessive cultivation in the vegetable industry. We grew lettuce (Lactuca sativa) under no-tillage in field trials on a sandy loam soil following a bare winter fallow or a cover-crop of subterranean clover (Trifolium subterraneum), and compared this with cultivation by rotary hoe. The clover died naturally in early summer or was desiccated in the spring to form a mulch of at least 5 t ha-1 on the soil surface. The experiment was carried out over a 2.5 year period. The first crop was grown during hot weather and the soil in the no-tillage treatments was only moderately compacted. The yield of lettuce was similar in the no-tillage and cultivated treatments, and increased by about 30% when a mulch was added to each treatment. The soil was artificially compacted after the first crop. The second crop was grown 18 months later, during cooler spring weather, and following two further cover-crops. The yield of no-tillage lettuce was only 40% of that obtained with cultivation. Yield in the no-tillage treatment was doubled in two different ways: (1) by the addition of a surface mulch, and (2) through changes to soil structure stimulated by a cover-crop in the absence of a mulch. The experiments showed that a well-managed cover-crop can significantly ameliorate a compacted sandy soil by modifying soil temperature, soil strength, and by stimulating the formation of biopores.



2004 ◽  
Vol 84 (3) ◽  
pp. 739-747 ◽  
Author(s):  
J. R. Moyer ◽  
J. Nitschelm ◽  
P. Regitnig ◽  
R. E. Blackshaw ◽  
H. C. Huang ◽  
...  

Sugarbeets (Beta vulgaris L.) are grown on intensively tilled-irrigated land in southern Alberta, which is subject to soil erosion by wind. Experiments were conducted on commercial fields near Burdett, AB, to determine the effect of the tillage system and previous crops on sugarbeet production. The previous crops were dry bean (Phaseolus vulgaris L.) or wheat (Triticum aestivium L.) and the tillage systems were conventional (moldboard plow, vibrashank cultivator, harrow, packer), minimum (double disc, self-cleaning harrow, glyphosate) or no tillage (glyphosate). After dry beans, sugarbeet fresh weight and extractable sugar yields were similar with all tillage systems. All of the tillage systems left less than 100 g m-2 of plant residue on the soil surface in the spring following dry beans, which is insufficient to protect the soil from wind erosion. After wheat, sugarbeet yields were similar with minimum and conventional tillage but lower with no tillage. Both minimum and no-tillage systems left sufficient plant residue on the soil surface to protect the soil from erosion (> 200 g m-2). Sugarbeet stand density following wheat was lower with no tillage than conventional or minimum tillage, reflecting poor seed placement and daily maximum soil temperature (5 cm depth) of up to 10°C lower under no tillage than conventional tillage. After wheat, there was a trend toward lower densities of hard-seeded annuals, such as redroot pigweed (Amaranthus retroflexus L.), after no tillage than conventional tillage. Of the cropping systems tested in this study, only the minimum tillage system after wheat provided optimum sugarbeet yield and left enough plant residue to protect the soil from wind erosion. Key words: Crop rotation, bean, wheat, sugarbeet, no-tillage



2001 ◽  
Vol 91 (6) ◽  
pp. 534-545 ◽  
Author(s):  
Walber L. Gavassoni ◽  
Gregory L. Tylka ◽  
Gary P. Munkvold

The dynamics of Heterodera glycines spatial patterns were studied under different tillage systems in two naturally infested soybean fields in Iowa from 1994 to 1997. At each location, there were four different tillage treatments (conventional tillage, reduced tillage, ridge tillage, and no tillage). Soil samples were taken from 98 contiguous quadrats (5.2 m2) per plot in the fall of 1994, before any tillage was performed, and in the spring of the following 3 years shortly after planting. Cysts were extracted from soil samples by elutriation and counted, and eggs were extracted from cysts and enumerated. Spatial patterns of H. glycines populations were characterized by geostatistical analysis and variance-to-mean (VM) ratios. Semivariance values were calculated for cyst and egg densities and semivariograms were constructed. In general, there was greater spatial dependence among cyst populations than egg populations. In one field with a strongly aggregated initial H. glycines population, tillage practices resulted in changes in spatial patterns of H. glycines populations, characterized by spherical-model semivariogram parameters (sill, nugget effect, and range of spatial dependence). These parameters indicated increasing aggregation over time in no tillage and ridge tillage treatments, but decreasing aggregation in reduced and conventional tillage treatments. There was an increase of 350% in sill values (maximum semivariance) for cyst populations after 3 years of no tillage, but in the conventional tillage treatment, sill values remained unchanged or decreased over time as tillage was implemented. Semivariograms for cyst and egg population densities revealed strong anisotropy (directional spatial dependence) along soybean rows, coincident with the direction of tillage practices. VM ratios for cyst counts increased each year in the no tillage and ridge tillage treatments, but decreased for 2 years in reduced tillage and conventional tillage treatments. Final VM ratios for cyst and egg counts were highest in the no tillage treatment. In a second field, with low initial aggregation of H. glycines populations, there was little measurable change in semivariogram parameters after 3 years of no tillage, but in the conventional tillage treatment, populations became less aggregated, as the range, sill, and the proportion of the sill explained by spatial dependence decreased for cyst population densities. Our results indicated that in soybean fields with initially aggregated populations of H. glycines, no tillage and ridge tillage systems promoted aggregation of the nematode population, whereas conventional and reduced tillage systems resulted in a less aggregated spatial pattern.



1999 ◽  
Vol 50 (6) ◽  
pp. 1073 ◽  
Author(s):  
A. Loi ◽  
P. S. Cocks ◽  
J. G. Howieson ◽  
S. J. Carr

Experiments measuring seed bank size, hardseededness, and seed softening of biserrula (Biserrula pelecinus L.) were conducted at Merredin and Perth in Western Australia. At Merredin, a mixture of 2 biserrula accessions was grazed, shallow cultivated, or left uncultivated and ungrazed. Seed bank size, seedling regeneration, and seed softening were measured over 2 years. At Perth, softening of biserrula, yellow serradella, and subterranean clover seeds grown at 2 sites (Binnu and Northam) was compared on the soil surface and after burial at 2 and 10 cm over a period of 2 years. Seed bank size of biserrula at Merredin ranged from 14000 to 17500 seeds/m2. Regeneration was greater in the second year (800–1700 seedlings/m2) than in the first year (40–600 seedlings/m2). In both years the shallow cultivated treatment recorded the highest number of seedlings. About 90% of biserrula and serradella seed remained hard after 2 years on the soil surface, compared with only about 10% of subterranean clover. Serradella softened more rapidly when buried 2 cm below the soil surface (8–12% hard) than it did on the soil surface (84–92% hard) (P<0.05). In contrast, the softening of subterranean clover decreased with increasing depth. Biserrula was intermediate, although it too softened most rapidly at 2 cm (78–95% hard compared with 82–97% on the surface) (P<0.05). Rate of seed softening in all species decreased with increasing depth of burial below 2 cm. Of the 4 accessions of biserrula, an accession from Greece (83% hard after 2 years exposure) was significantly softer than the other accessions. The results indicate that biserrula is very hardseeded, although there is sufficient variation in hardseededness for the selection of somewhat softer lines. Its pattern of softening suggests that biserrula may be successful in the ley farming system (crop/pasture rotations) of southern Australia.



Nativa ◽  
2019 ◽  
Vol 7 (5) ◽  
pp. 494
Author(s):  
Carla Da Penha Simon ◽  
Edney Leandro da Vitória ◽  
Elcio Das Graça Lacerda ◽  
Yago Soares Avancini ◽  
Tatiana Fiorotti Rodrigues ◽  
...  

Objetivou-se quantificar o CO2,atributos químicos e físicos do solo são influenciados por diferentes manejos de preparo do solo. O Delineamento experimental adotado foi inteiramente casualizado, sendo os tratamentos: Sistema de Plantio Direto (SPD), Cultivo Mínimo e Preparo Convencional (PC), e como referência: área de vegetação nativa (Mata), contando com seis repetições cada variável de estudo. Além da comparação por teste médias, foi realizada uma análise exploratória das leituras nos sistemas de preparo do solo, onde o CO2 foi traduzido graficamente num diagrama o box-plot. As variáveis avaliadas foram: CO2 obtido por meio de um analisador de gás infravermelho; os atributos físicos do solo: Densidade do solo (Ds), Volume Total de Poros (VTP), Macroporosidade (Ma), Microporosidade (Mi), Resistência a Penetração do solo (RPS) e o atributo químico: carbono orgânico total (COT). O fluxo CO2 do solo apresentou diferença significativa entre o SPD e o PC; valores médios encontrados para SPD, CM, Mata e PC foram 2,30; 2,25; 2,18; e 1,39 μmolCO2m−2 s−1, respectivamente; o COT apresentou seu maior valor na área de Mata (32,95 gkg-1) diferindo estatisticamente das demais áreas. Observou-se uma menor emissão de CO2 do solo no PC, pois o sistema apresenta baixo aporte de carbono orgânico.Palavras-chave: sistema de preparo convencional; cultivo mínimo; preparo convencional; carbono orgânico total. CO2 EMISSION, PHYSICAL ATTRIBUTES AND TOTAL ORGANIC CARBON IN DIFFERENT SOIL PREPARATION SYSTEMS ABSTRACT: The objective was to quantify the CO2, chemical and physical attributes of the soil are influenced by different management of soil preparation. The experimental design was completely randomized, with the treatments: no-tillage (NT), minimum tillage (MT) and conventional tillage (CT), and as reference:  native forest (NF), with six replicates each study variable. In addition to the mean test comparison, an exploratory analysis of the readings was performed in the soil preparation systems, where CO2 was graphically translated into a box-plot diagram. The variables evaluated were: CO2 obtained by means of a infrared gas analyzer; density (Bd), total pore volume (TPV), macroporosity (Ma), microporosity (Mi), resistance to soil penetration (RSP) and chemical attribute: total organic carbon (TOC). The CO2 soil flux presented a significant difference between NT and CT; where respectively the mean values found for SPD, CM, Mata and PC were 2.30; 2.25; 2.18; and 1.39 μmolCO2m-2s-1; the COT had its highest value in the Mata area (32.95 gkg-1), differing statistically from the other areas. It was observed a lower CO2 emission of the soil in the PC, because the system has low input of organic carbon.Keywords: no-tillage; conventional tillage; minimum tillage; total organic carbon.



Sign in / Sign up

Export Citation Format

Share Document