scholarly journals Influence of continuous cropping on corn and soybean pathogens

2017 ◽  
Vol 43 (1) ◽  
pp. 14-19 ◽  
Author(s):  
Camila Ranzi ◽  
Juliane Nicolodi Camera ◽  
Carolina Cardoso Deuner

ABSTRACT The objective of this study was to evaluate the influence of two tillage programs (conventional and no-tillage) and different rotations with soybeans and corn on the occurrence of Fusarium species. The work was conducted in the experimental field and Seed Laboratory at Iowa State University. The treatments were: tillage (no-tillage and conventional tillage), crop (corn and soybeans) and three different cropping sequences for corn and soybeans, respectively. Treatment with corn: (1) the first year after four years of soybeans (1C); (2) alternating corn and soybeans each year (C / SB); (3) Continuous corn (C). Treatment with soybeans; (1) the first year after four years of corn (1S); (2) alternating soybeans and corn each year (SB / C); (3) Continuous soybeans (S). Two plant counts were performed in two stages in soybean (VC and V3) and corn (V1 and V3). The root system of ten plants were collected in the vegetative stages V2 and V5 for soybeans and corn. The fungi were isolated from the roots, and the Fusarium species were identified based on the most distinctive morphological characteristics. Nine species were identified in both soybeans and corn, namely F. acuminatum, F. equiseti, F. graminearum, F. oxysporum, F. proliferatum, F. solani, F. subglutinans, F. verticillioides and F. virguliforme. There were no significant differences among the treatments concerning the Fusarium species composition, for both soybeans and corn. In soybeans Fusarium oxysporum was the most frequently observed saprophyte species, followed by F. solani. For corn the main trends in the data was the predominance in all treatments of F. solani, whose highest frequency was in the no-tillage system.

2010 ◽  
Vol 45 (12) ◽  
pp. 1331-1341 ◽  
Author(s):  
Homero Bergamaschi ◽  
Genei Antonio Dalmago ◽  
João Ito Bergonci ◽  
Cleusa Adriane Menegassi Bianchi Krüger ◽  
Bruna Maria Machado Heckler ◽  
...  

The objective of this work was to evaluate changes in the photosynthetic photon flux density (PPFD) interception efficiency and PPFD extinction coefficient for maize crop subjected to different soil tillage systems and water availability levels. Crops were subjected to no-tillage and conventional tillage systems combined with full irrigation and non-irrigation treatments. Continuous measurements of transmitted PPFD on the soil surface and incoming PPFD over the canopy were taken throughout the crop cycle. Leaf area index and soil water potential were also measured during the whole period. Considering a mean value over the maize cycle, intercepted PPFD was higher in the conventional tillage than in the no-tillage system. During the initial stages of plants, intercepted PPFD in the conventional tillage was double the PPFD interception in the no-tillage treatment. However, those differences were reduced up to the maximum leaf area index, close to tasseling stage. The lowest interception of PPFD occurred in the conventional tillage during the reproductive period, as leaf senescence progressed. Over the entire crop cycle, the interception of PPFD by the non-irrigated plants was about 20% lower than by the irrigated plants. The no-tillage system reduced the extinction coefficient for PPFD, which may have allowed a higher penetration of solar radiation into the canopy


2019 ◽  
Vol 11 (17) ◽  
pp. 4522 ◽  
Author(s):  
Magdalena Ruiz ◽  
Encarna Zambrana ◽  
Rosario Fite ◽  
Aida Sole ◽  
Jose Luis Tenorio ◽  
...  

The increasing spread of conservation agriculture demands that the next generation of wheat varieties includes cultivars capable of maintaining satisfactory yields with lower inputs and under uncertain climate scenarios. On the basis of the genetic gains achieved during decades of selection oriented to yield improvements under conventional crop management, it is important that novel breeding targets are defined and addressed. Grain yield, yield-related traits, and phenological and morphological characteristics, as well as functional quality parameters have been analyzed for six varieties each of bread and durum wheat, under minimum tillage and no-tillage. During the three-year experiment, the climatic conditions at the field trial site were characterized by low rainfall, although different degrees of aridity—from moderate to severe—were experienced. Differences were found between these two soil management practices in regard to the varieties’ yield stability. A positive influence of no-tillage on traits related to grain and biomass yield was also evidenced, and some traits among the examined seemed involved in varietal adaptation to a particular non-conventional tillage system. The study also confirmed some breeding targets for improved performance of wheat genotypes in conservation agroecosystems. These traits were represented in the small set of traditional varieties analysed.


2015 ◽  
Vol 29 (4) ◽  
pp. 467-473 ◽  
Author(s):  
Veronica Muñoz-Romero ◽  
Luis Lopez-Bellido ◽  
Rafael J. Lopez-Bellido

Abstract Soil temperature is a factor that influences the rates of physical, chemical, and biological reactions in soils and has a strong influence on plant growth. A field study was conducted during 2006-2007 and 2009-2010 on a typical rainfed Mediterranean Vertisol to determine the effects of the tillage system and the crop on soil temperature. The experimental treatments were the tillage system (no-tillage and conventional tillage) and the crop (wheat and faba bean). Soil temperature was measured at a 20 cm depth at 1 h intervals from December 1st to November 30th of 2006-2007 and 2009-2010. There was a highly significant relationship between air temperature (both maximum and minimum) and soil temperature for the two tillage systems. Soil temperature was similar in the growing season for both crops but was higher in the conventional tillage than in the no-tillage system, with differences between 0.7 and 2.6°C depending on the month of the year. A higher soil temperature with conventional tillage can be beneficial in the cold sowing period (November-December), improving crop establishment. In contrast, in critical periods with water deficits (spring) during which grain formation occurs, the lower temperature corresponding to the no-tillage system would be more favourable.


Weed Science ◽  
1999 ◽  
Vol 47 (1) ◽  
pp. 67-73 ◽  
Author(s):  
J. Dorado ◽  
J. P. Del Monte ◽  
C. López-Fando

In a semiarid Mediterranean site in central Spain, field experiments were conducted on a Calcic Haploxeralf (noncalcic brown soil), which had been managed with three crop rotations and two tillage systems (no-tillage and conventional tillage) since 1987. The crop rotations consisted of barley→vetch, barley→sunflower, and a barley monoculture. The study took place in two growing seasons (1992–1994) to assess the effects of management practices on the weed seedbank. During this period, spring weed control was not carried out in winter crops. In the no-tillage system, there was a significant increase in the number of seeds of different weed species: anacyclus, common purslane, corn poppy, knotted hedge-parsley, mouse-ear cress, spring whitlowgrass, tumble pigweed, venus-comb, andVeronica triphyllos.Conversely, the presence of prostrate knotweed and wild radish was highest in plots under conventional tillage. These results suggest large differences in the weed seedbank as a consequence of different soil conditions among tillage systems, but also the necessity of spring weed control when a no-tillage system is used. With regard to crop rotations, the number of seeds of knotted hedge-parsley, mouse-ear cress, and spring whitlowgrass was greater in the plots under the barley→vetch rotation. Common lambsquarters dominated in the plots under the barley→sunflower rotation, whereas venus-comb was the most frequent weed in the barley monoculture. Larger and more diverse weed populations developed in the barley→vetch rotation rather than in the barley→sunflower rotation or the barley monoculture.


2010 ◽  
pp. 174-179
Author(s):  
Daniel Dicu ◽  
Iacob Borza ◽  
Dorin Tarau

The researches are inscribed on line of substantiation of durable agricultural system, having main objective the prominence ofquantitative and qualitative modifications made on agro-system level under the effect of no-tillage system for wheat, maize and soybeans.The experimental field is placed on a cambium chernozem, with a medium content of clay, dominant in the Prodagro West Arad agrocentreand representative for a large surface in the Banat-Crisana Plain.The passing to no-till system change the structure of technological elements, through less soil works, so the impact on agro-system isdifferent comparing with conventional tillage, first less the intervention pressure on agro-system ant secondly appears new interactions, newequilibriums and disequilibriums.Considering the evolution of soil humidity, the observations made monthly (by taking soil samples and laboratory determinations) forthe three cultures showed that in the no-till system, there are more uniform values in the soil profile, and in the variants where the deep workof soil was made it could be observed a low increase of the water volume in the soil.


2020 ◽  
Vol 87 ◽  
Author(s):  
Djavan Pinheiro Santos ◽  
Robélio Leandro Marchão ◽  
Ronny Sobreira Barbosa ◽  
Juvenal Pereira da Silva Junior ◽  
Everaldo Moreira da Silva ◽  
...  

ABSTRACT: The soil macrofauna is fundamental for the maintenance of soil quality. The aim of this study was to characterize the soil macrofauna under different species of cover crops, including monoculture or intercropping associated to two types of soil management in the southwest region of Piauí state. The study was carried out in an Oxisol (Latossolo Amarelo, according to Brazilian Soil Classification System) in the municipality of Bom Jesus, Piauí, distributed in 30 m2 plots. Testing and evaluation of the soil macrofauna were conducted in a 9 × 2 strip factorial design, with combinations between cover crops/consortia and soil management (with or without tillage), with four replications. Soil monoliths (0.25 × 0.25 m) were randomly sampled in each plot for macrofauna at 0‒0.1, 0.1‒0.2, and 0.2‒0.3 m depth, including surface litter. After identification and counting of soil organims, the relative density of each taxon in each depth was determined. The total abundance of soil macrofauna quantified under cover crops in the conventional and no-tillage system was 2,408 ind. m-2, distributed in 6 classes, 16 orders, and 31 families. The results of multivariate analysis show that grass species in sole cropping systems and no-tillage presents higher macrofauna density, in particular the taxonomic group Isoptera. No-tillage also provided higher richness of families, where Coleoptera adult were the second more abundant group in no-tillage and Hemiptera in conventional tillage.


2008 ◽  
Vol 23 (2) ◽  
pp. 107-114
Author(s):  
Milena Simic ◽  
Nebojsa Momirovic ◽  
Zeljko Dolijanovic ◽  
Zeljko Radosevic

The effects of different herbicide combinations: control (1), alachlor+linuron (2), and alachlor+linuron+imazethapyr (3) were investigated in double-cropped soybean grown in two row spacing variants, 38 cm and 76 cm, under conventional tillage (CT) or no-tillage (NT). In trials conducted on a sandy loam soil at Zemun Polje, high weediness had a negative effect of on the yield of double-cropped soybean, especially at the higher row spacing tested and with no-tillage. Regression and correlation data revealed a dependence of weediness in double-cropped soybean on tillage system and herbicide combination, and dependence of soybean yield on tillage system.


2018 ◽  
Vol 71 (3) ◽  
Author(s):  
Dorota Gawęda ◽  
Andrzej Woźniak ◽  
Elżbieta Harasim

In-crop weed infestation is affected by both habitat conditions and agronomic practices, including the forecrop and tillage treatments used. This study evaluated the effect of the forecrop and the tillage system on species composition, number and dry weight of weeds in a winter wheat ‘Astoria’. A field study was carried out over the period 2014–2017 at the Uhrusk Experimental Farm (SE Poland), on a mixed rendzina soil with a grain-size distribution of sandy loam. Wheat was grown in a four-course crop rotation: soybean – winter wheat – rapeseed – winter wheat. The experimental factors were as follows: a forecrop of winter wheat (soybean and winter rapeseed) and a tillage system (ploughing and no-tillage). <em>Avena fatua</em> was the most frequently occurring weed in the wheat crop sown after soybean, whereas after winter rapeseed it was <em>Viola arvensis</em>. <em>Viola arvensis</em> was the dominant weed under both tillage systems. In all experimental treatments, the species <em>Viola arvensis</em> and <em>Cirsium arvense</em> were characterized by the highest constancy (Constancy Class V and IV), and also <em>Veronica arvensis</em> after the previous winter rapeseed crop. In the wheat crop sown after winter rapeseed, the number of weeds was found to be higher by 62.1% and the weed dry weight higher by 27.3% compared to these parameters after the previous soybean crop. A richer floristic composition of weeds was also observed in the stand after winter rapeseed. Under conventional tillage conditions, compared to no-tillage, the number of weeds was found to be lower by 39.7% and their dry weight by 50.0%. An increase in the numbers of the dominant weed species was also noted in the untilled plots.


2014 ◽  
Vol 67 (2) ◽  
pp. 117-122 ◽  
Author(s):  
Tomasz R. Sekutowski ◽  
Janusz Smagacz

An experiment, conducted over the period 2008–2010, evaluated the effect of tillage system on the occurrence and species composition of anthropophytes in winter wheat, maize and spring wheat. Regardless of crop plant and tillage system, anthropophytes (73.9%), represented by archaeophytes and kenophytes, were the main component of the flora in the crops studied, whereas apophytes accounted for the remaining 26.1%. Most archaeophytes (13 species) were found in the spring wheat crop under no-tillage, while their lowest number (6 species) occurred in the spring wheat crop under conventional tillage. The only kenophyte, <em>Conyza canadensis</em>, was found to occur in the spring wheat and maize crops in the no-tillage system. The following taxa were dominant species among archeophytes: <em>Geranium pusillum</em>, <em>Anthemis arvensis, </em>and <em>Viola arvensis </em>(regardless of tillage system and crop plant), <em>Anthemis arvensis </em>(in spring wheat – conventional tillage), <em>Echinochloa crus-galli </em>and <em>Setaria glauca </em>(in maize – reduced tillage and no-tillage), <em>Chenopodium album </em>(in maize – no-tillage) as well as <em>Apera spica-venti</em>, <em>Anthemis arvensis </em>and <em>Papaver rhoeas </em>(in winter wheat – no-tillage).


Weed Science ◽  
1977 ◽  
Vol 25 (6) ◽  
pp. 511-514 ◽  
Author(s):  
W.E. Chappell ◽  
L.A. Link

Burley tobacco (Nicotiana tabacum L. ‘Kentucky 14′) was grown as a no-tillage crop in 1974 and 1975 by planting tobacco directly into an existing stand of orchardgrass (Dactylis glomerata L.) or rye (Secale cereale L.). Paraquat (1,1′-dimethyl-4,4′bipyridium ion) and glyphosate [N-(phosphonomethyl)glycine] were used to kill existing vegetation. Benefin (N-butyl-N-ethyl-α,α,α-trifluoro-2,6-dinitro-p-toluidine), oryzalin (3,5-dinitro-N4,N4-dipropylsulfaniiamide), metribuzin [4-amino-6-tert-butyl-3-(methylthio)-as-triazin-5(4H)one], and chlorbromuron [3-(4-bromo-3-chlorophenyl), 1-methoxy-1-methylurea] were used to control annual grasses and broadleaf weeds.Glyphosate was generally more effective than paraquat in killing existing vegetation. There was some injury to the tobacco associated with the glyphosate and paraquat treatments, but this was generally confined to those plants which came into contact with the treated herbage. Metribuzin caused severe damage to the tobacco and was discontinued after the first year. Chlorbromuron caused little injury if kept on the surface but injured the tobacco if incorporated by cultivation as in conventional tillage. Benefin and oryzalin caused little or no injury to the tobacco. All four herbicides gave adequate control of annual grasses and broadleaf weeds.


Sign in / Sign up

Export Citation Format

Share Document