Autoradiographic Detection of Lesser Cornstalk Borer (Lepidoptera: Pyralidae) Eggs in Soil Environments

1990 ◽  
Vol 25 (3) ◽  
pp. 458-462
Author(s):  
J. M. Cheshire ◽  
J. N. All

A nondestructive method of detecting lesser cornstalk borer, Elasmopalpus lignosellus (Zeller), eggs in soil is outlined. Fourth instar larvae were fed a diet containing radioactive phosphorus (4 μ Ci/g), and eggs laid by females that emerged from these larvae contained sufficient radioactivity to expose X-ray film. Fecundity, oviposition rates, and longevity were similar for 32P-labeled adult females and unlabeled adult females. In greenhouse tests using corn planted in simulations of conventional tillage and no-tillage conditions, eggs were autoradiographically detected in soil and on plant tissue.

2014 ◽  
Vol 34 (6) ◽  
pp. 1162-1174 ◽  
Author(s):  
José M. G. Beraldo ◽  
Francisco de A. Scannavino Junior ◽  
Paulo E. Cruvinel

The study aimed to evaluate a methodology to quantify the porosity of the soil using computed tomography in areas under no-tillage, conventional tillage and native forest. Three soil management systems were selected for the study: forest, conventional tillage and no-tillage. In each soil management system, undisturbed soil samples were collected in the surface layer (0.0 to 0.10 m). The tomographic images were obtained using a X-ray microtomography. After obtaining the images, they were processed, and a methodology was evaluated for image conversion into numerical values. The statistical method which provided the greatest accuracy was the percentile method. The methodology used to analyze the tomographic image allowed quantifying the porosity of the soil under different soil management. The method enabled the characterization of soil porosity in a non-evasive and non-destructive way.


2016 ◽  
Vol 9 (3) ◽  
pp. 778
Author(s):  
Viviane Capoane ◽  
Ivan Renato Cardoso Krolow ◽  
Danilo Rheinheimer dos Santos ◽  
Lutécia Beatriz Canalli

Neste trabalho, determinaram-se os teores totais das substâncias químicas presentes em um Latossolo Vermelho aluminoférrico utilizando a técnica de espectroscopia total de fluorescência de raios-X. A pesquisa teve como objetivo criar uma base de dados geoquímica para os solos da região sudoeste do Paraná; comparar os resultados com valores de referência nacional e internacional; avaliar o efeito dos sistemas plantio direto versus convencional de cultivo e; de plantas de cobertura de inverno, na geoquímica do solo de um experimento de longa duração. As coletas de solo se deram em três locais distintos, em três camadas (0-10, 10-20 e 20-40 cm). A técnica utilizada forneceu de maneira rápida e limpa a impressão digital química do solo e os mesmos servem de background para o sudoeste do Paraná. Os teores de elementos químicos preconizados por organizações nacionais e internacionais não estão alinhados com os teores observados em áreas não antropizadas do estado do Paraná. Os resultados obtidos também mostraram que 29 anos após a implantação do experimento, a fertilidade natural foi alterada e que, a substituição da vegetação nativa por sistemas cultivados levou a exportação de algumas substâncias químicas do solo como SO3, MnO, Co e, ao acúmulo de outras como CaO, K2O e MgO. No sistema plantio direto (0-10 cm) concentraram-se os maiores teores de substâncias de origem antropogênica. O sistema convencional de cultivo apresentou diferenciação significativa nos teores entre as plantas de cobertura e não significativa entre as camadas de solo.   A B S T R A C T In this work, the total chemical element levels in a Rhodic Hapludox were determined using total  X-ray fluorescence spectroscopy. The research aimed to create a geochemical database of soils in the southwestern region of Paraná; compare the values obtained with national and international reference values; evaluate the effect of no-tillage versus conventional tillage systems and; coverage plants on the soil geochemistry in a long term experiment. Soil collections were made in three different locations, each in three layers (0-10, 10-20 and 20-40 cm). The technique gave a quick, clean chemical digital impression of the soil which also can be used as a background for the southwestern Paraná. The levels of chemicals recommended by national and international organizations are not aligned with the levels observed in non-disturbed areas of Paraná State. The results also showed that twenty nine years after the beginning of the experiment, the natural fertility changed and that, with the substitution of native vegetation for cultivation systems, levels of some components such as SO3, MnO and Co decreased and those of others such as CaO, K2O and MgO increased. In soils for which no-tillage systems (0-10 cm) is the largest concentrations of anthropogenic substances. The conventional tillage systems gave levels very different from those found in soils under coverage plants and not significantly different between the soil layers. Keywords: soil management, cover crops, no tillage, conventional tillage, geochemistry.   


2021 ◽  
Vol 41 (2) ◽  
Author(s):  
Blessing Mhlanga ◽  
Laura Ercoli ◽  
Elisa Pellegrino ◽  
Andrea Onofri ◽  
Christian Thierfelder

AbstractConservation agriculture has been promoted to sustainably intensify food production in smallholder farming systems in southern Africa. However, farmers have rarely fully implemented all its components, resulting in different combinations of no-tillage, crop rotation, and permanent soil cover being practiced, thus resulting in variable yield responses depending on climatic and soil conditions. Therefore, it is crucial to assess the effect of conservation agriculture components on yield stability. We hypothesized that the use of all three conservation agriculture components would perform the best, resulting in more stable production in all environments. We evaluated at, eight trial locations across southern Africa, how partial and full implementation of these components affected crop yield and yield stability compared with conventional tillage alone or combined with mulching and/or crop rotation. Grain yield and shoot biomass of maize and cowpea were recorded along with precipitation for 2 to 5 years. Across different environments, the addition of crop rotation and mulch to no-tillage increased maize grain by 6%, and the same practices added to conventional tillage led to 13% yield increase. Conversely, adding only mulch or crop rotation to no-tillage or conventional tillage led to lower or equal maize yield. Stability analyses based on Shukla’s index showed for the first time that the most stable systems are those in which mulch is added without crop rotation. Moreover, the highest yielding systems were the least stable. Finally, additive main effects and multiplicative interaction analysis allowed clarifying that mulch added to no-tillage gives stable yields on sandy soil with high rainfall. Similarly, mulch added to conventional tillage gives stable yield on sandy soil, but under low rainfall. This is the first study that highlighted the crucial role of mulch to enhance the stability and resilience of cropping systems in southern Africa, supporting their adaptability to climate change.


1997 ◽  
Vol 24 (1) ◽  
pp. 52-59
Author(s):  
S. D. Stewart ◽  
K. L. Boweri ◽  
T. P. Mack ◽  
J. H. Edwards

Abstract Three row spacings and two planting dates for peanuts, Arachis hypogaea L., were examined in 1993 and 1994 to determine the influence of the canopy environment on lesser cornstalk borer, Elasmopalpus lignosellus (Zeller) (Lepidoptera: Pyralidae), other arthropods, and alflatoxigenic fungi. Climatically, 1993 and 1994 were disparate years. Decreasing row spacing increased relative leaf area and light interception by the canopy but, compared to difference between planting dates or years, had a relatively small impact on soil temperatures and relative humidity within the canopy. Late planting produced smaller plants, retarded canopy development, and reduced yield in both years, but especially in 1993 when it was hot and dry. The wide row spacing did not yield as well as twin and normal row spacings in either year. Lesser cornstalk borer damage and aflatoxin concentration were higher in the late planting than in the early planting of 1993, but were unaffected by row spacing. Fewer predatory arthropods were caught as row spacing decreased in both beat and pitfall samples, but planting date had variable effects. Prevailing climatic conditions and planting date appeared to be more important in influencing the canopy environment and pest densities than was row spacing.


2006 ◽  
Vol 20 (3) ◽  
pp. 622-626 ◽  
Author(s):  
Patrick W. Geier ◽  
Phillip W. Stahlman ◽  
John C. Frihauf

Field experiments were conducted during 2003 and 2004 to compare the effectiveness of KIH-485 and S-metolachlor for PRE weed control in no-tillage and conventional-tillage corn. Longspine sandbur control increased as KIH-485 or S-metolachlor rates increased in conventional-tillage corn, but control did not exceed 75% when averaged over experiments. Both herbicides controlled at least 87% of green foxtail with the exception of no-tillage corn in 2004, when KIH-485 was more effective than S-metolachlor at lower rates. Palmer amaranth control ranged from 85 to 100% in 2003 and 80 to 100% in 2004, with the exception of only 57 to 76% control at the lowest two S-metolachlor rates in 2004. Puncturevine control exceeded 94% with all treatments in 2003. In 2004, KIH-485 controlled 86 to 96% of the puncturevine, whereas S-metolachlor controlled only 70 to 81%. Mixtures of atrazine with KIH-485 or S-metolachlor generally provided the most effective control of broadleaf weeds studied.


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.


2003 ◽  
Vol 60 (3) ◽  
pp. 581-586 ◽  
Author(s):  
Ildegardis Bertol ◽  
Eloy Lemos Mello ◽  
Jean Cláudio Guadagnin ◽  
Almir Luis Vedana Zaparolli ◽  
Marcos Roberto Carrafa

Water erosion causes soil degradation, which is closely related to nutrient losses either in, the soluble form or adsorbed to soil particles, depending mainly on the adopted soil management system. This study was carried out in São José do Cerrito, SC, Brazil, between March 2000 and June 2001. The objective was to quantify available nitrogen, phosphorus, potassium, calcium and magnesium losses in water erosion obtained with simulated rainfall in the following soil management systems: conventional tillage with no-crop (bare soil) (BS), conventional tillage with soybean (CT), reduced tillage with soybean (RT), no tillage with soybean on a desiccated and burned natural pasture (DBNP), and no tillage with soybean on a desiccated natural pasture (DNP). A rotating boom rainfall simulator was used to perform three rainfall tests with constant intensity of 64 mm h-1 and sufficient duration to reach constant runoff rate, on a clayey-loam, well-structured Typic Hapludox, with an average slope of 0.18 m m-1. The first test was carried out five days before soybean emergence and the second and third at 30 and 60 days, respectively. The nutrient concentration in water and total losses of nitrogen, phosphorus, potassium, calcium and magnesium were higher under CT than in the other soil management systems.


2011 ◽  
Vol 57 (1) ◽  
pp. 21-30
Author(s):  
Božena Šoltysová ◽  
Martin Danilovič

Tillage in Relation to Distribution of Nutrients and Organic Carbon in the SoilChanges of total nitrogen, available phosphorus, available potassium and soil organic carbon were observed on gleyic Fluvisols (locality Milhostov) at the following crops: grain maize (2005), spring barley (2006), winter wheat (2007), soya (2008), grain maize (2009). The experiment was realized at three soil tillage technologies: conventional tillage, reduced tillage and no-tillage. Soil samples were collected from three depths (0-0.15 m; 0.15-0.30 m; 0.30-0.45 m). The ratio of soil organic carbon to total nitrogen was also calculated.Soil tillage affects significantly the content of total nitrogen in soil. The difference between the convetional tillage and soil protective tillages was significant. The balance showed that the content of total nitrogen decreased at reduced tillage by 5.2 rel.%, at no-tillage by 5.1 rel.% and at conventional tillage by 0.7 rel.%.Similarly, the content of organic matter in the soil was significantly affected by soil tillage. The content of soil organic carbon found at the end of the research period was lower by 4.1 rel.% at reduced tillage, by 4.8 rel.% at no-tillage and by 4.9 rel.% at conventional tillage compared with initial stage. The difference between the convetional tillage and soil protective tillages was significant.Less significant relationship was found between the soil tillage and the content of available phosphorus. The balance showed that the content of available phosphorus was increased at reduced tillage (by 4.1 rel.%) and was decreased at no-tillage (by 9.5 rel.%) and at conventional tillage (by 3.3 rel.%).Tillage did not significantly affect the content of available potassium in the soil.


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