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In organic production systems, penalties in cereal forage yield and low crude protein (CP) concentration are mainly caused by limited soil nitrogen (N) availability, which can be addressed by using cereal/grain legume bi-cropping systems. To confirm this, a bi-cropping experiment with spring wheat cv. Paragon and faba beans cvs. Fuego and Maris Bead were conducted in 2 years, using a randomised complete block design and sowing the crops in a replacement design series. In 2016, the wheat forage yield in sole cropping exceeded that in bi-cropping by 58%. In 2015, the wheat forage harvest index (HI) in bi-cropping was 14% higher than that in sole cropping, but in 2016 it was 7% lower. In both years, bi-cropping increased the CP and the grain N uptake in the wheat compared with that sole cropping, by 25% and 17%, respectively. The chlorophyll concentration index (CCI) in the wheat was 2.2 times higher in bi-cropping than in sole cropping and 34% higher in the alternate rows systems compared with the broadcast system. In 2015, the efficiency of N use (NLER) in bi-cropping was 50.7% higher than that in sole cropping. Alternate row bi-cropping improved NLER over broadcast by 37.9%. Faba bean rust disease was more severe in Fuego than in Maris Bead. In conclusion, bi-cropping in uniform alternate row spacing can improve productivity and nutritional quality of wheat forage, compared with sole cropping. The bi-crop bean cultivars Fuego and Maris Bead can, improve wheat straw CP and reduce rust disease severity, respectively. [ABSTRACT FROM AUTHOR]

This article explores the history and politics of American-funded food demonstration buses ("kitchen cars") in postwar Japan. Their express mission was to transform the Japanese national diet. I make two primary arguments. First, at least in the short to medium term, the kitchen cars were a win-win for both the United States and Japan. On the one hand, Japan benefited because the kitchen cars taught Japanese women how to cook cheap, nutritious, mostly easy dishes to improve the health of their families and the nation. On the other hand, these menus were planned specifically to increase consumption of American agricultural products, especially wheat, soy, and corn. For US agricultural and political interests, in addition to supporting the economic recovery and political stability of a Cold War ally, the kitchen cars – along with the school lunch program – were instrumental in teaching Japan to accept and consume American produce. My second argument concerns the reasons for the kitchen cars' success. I identify the following two factors: staffing by mostly female professional nutritionists, who combined authority with approachability for the kitchen cars' main audiences of middle-aged, married women; and the kitchen cars' mobility, which allowed them to reach even remote villages and hamlets. [ABSTRACT FROM AUTHOR]

Field experiments were conducted from April 2015 to September 2016 at the Royal Agricultural University, UK to explore the impact of drilling pattern and species mixtures on weed growth and forage yield. The bi-crops of spring field bean (Vicia faba) cv. Maris Bead and Fuego with spring wheat (Triticum aestivum) cv. Paragon were evaluated at four drilling patterns in a randomized complete block design with four replicates and compared against their respective sole crops. Weed DM was 59% higher in the sole cropping systems than the bi-cropping systems. The sole cropping systems outperformed the bi-cropping systems for wheat (in 2016 only) and for bean forage DM yield. However, the bi-cropping systems produced higher total forage DM yields than sole cropping systems. Weed DM was higher in broadcast than in alternate rows systems. Bean forage DM was 74% higher in treatments with alternate rows than in the broadcast treatment. Wheat forage DM was not affected by the drilling patterns. Maris Bead had higher forage DM than Fuego (in 2016 only). It was concluded that bi-cropping can increase land productivity per unit area over sole cropping, whilst improving forage DM yield and providing low cost integrated weed management. Alternate row drilling can improve bi-cropping productivity over the broadcast practice. Abbreviations: LER - Land Equivalent Ratio [ABSTRACT FROM AUTHOR]

In I Amber Waves: The Extraordinary Biography of Wheat, from Wild Grass to World Megacrop i , ecologist and Professor Catherine Zabinski accounts for the co-development of wheat and the human species (5). I Amber Waves: The Extraordinary Biography of Wheat, from Wild Grass to World Megacrop's i strengths and weaknesses go hand in hand: the book is expansive, covering a planetary history from blue-green algae to today. While Zabinski's survey of wheat's evolutionary path is significant, I Amber Waves i is also the story of how wheat has moved the human species forward, how humans have moved wheat forward, and what the crop means to society. [Extracted from the article]

Tempered radicals are change agents who experience the dominant culture as a violation of the integrity and authenticity of their personal values and beliefs. They seek to move forward whilst challenging the status quo. Does the concept provide a useful analytic lens through which the strategies of women and men farmer innovators, who are 'doing things differently' in agriculture, can be interpreted? What are their strategies for turning ambivalence and tension to their advantage? The paper uses research data derived from two wheat-growing communities in Oromia Region, Ethiopia, an area characterized by generally restrictive gendered norms and a technology transfer extension system. The findings demonstrate that women and men innovators actively interrogate and contest gender norms and extension narratives. Whilst both women and men innovators face considerable challenges, women, in particular, are precariously located 'outsiders within,' negotiating carefully between norm and sanction. Although the findings are drawn from a small sample, they have implications for interventions aiming to support agricultural innovation processes which support women's, as well as men's, innovatory practice. The framework facilitates a useful understanding of how farmer innovators operate and in particular, significant differences in how women and men interrogate, negotiate and align themselves with competing narratives. [ABSTRACT FROM AUTHOR]

A two-year ley field experiment was established in May 2009 with six combinations of red clover, perennial ryegrass and cocksfoot, and two fallow control plots, to determine the impact of ‘cut and remove’ of the crops three times or ‘cut and mulch’ once annually on biomass yield, nitrogen (N) accumulation, soil mineralization and subsequent cereal performance. Farmyard manure was added to one of the fallow treatments at the beginning of the arable phase. The experiment was conducted on a clay loam soil at Moreton-in-Marsh, Gloucestershire, UK (NGR SP 217 323). During the ley fertility-building phase, there was no evidence that red clover (RC) had a synergistic effect on grass productivity when in mixtures, irrespective of cutting system. Accumulated above ground N over the 2 years was greater in cut/removed red clover-based leys (330–365 kg ha− 1) grass and fallow plots. In cut/mulched leys, RC was higher (113 kg ha− 1) than the rest. Soil potential mineralizable N (PMN) was not related to ley N yields but was consistently high in the red clover/ryegrass/cocksfoot (RCRGCF) treatments during winter and spring wheat. There was no indication that wheat yields and quality were improved following any red clover combinations or cutting regimes. These results suggest mixing RC with two grasses, RG and CF are likely to improve soil mineralization potential. Nevertheless, growing red clover leys over 2 years and mulching once annually under variable weather could limit soil N accumulation. In such conditions, growing red clover leys for a shorter period and removing herbage may be a better option. [ABSTRACT FROM AUTHOR]

The use of microbial soil inoculants in agriculture is of increasing interest among growers and scientists. This study aimed to determine the effects of a commercially available arbuscular mycorrhizal fungus (AMF) inoculant, an on-farm produced AMF inoculant, and an on-farm produced indigenous microbial inoculant on bread wheat (Triticum aestivumL.) AMF colonization, biomass accumulation, nutrient uptake and recovery, and grain yield and protein in a containerized greenhouse experiment and two years of field trials conducted in Maine, USA. The inoculants were compared with respective controls (sterilized inoculants) and the levels of N, P and K were equalized across treatments. Both AMF inoculants enhanced AMF colonization in a greenhouse potting mix containing unsterilized field soil, but only the on-farm produced AMF increased aboveground biomass and phosphorus (P) uptake and recovery. No differences were observed among inoculants and their relative controls in the field. However, the indigenous microbial inoculant (IMO+) increased wheat aboveground biomass, nutrient uptake, nutrient recovery and grain yield when compared with the mycorrhizal inoculants, but no increases were observed when contrasted against its control (IMO − ). Wheat growth enhancements from IMO were likely due to nutrient supply from the compost-based material in which it was produced. Results demonstrate that a mycorrhizal inoculant produced on-farm can increase wheat AMF colonization, aboveground biomass, and P uptake and recovery in a containerized setting. Otherwise differences between inoculants and their relative controls were limited, perhaps due to competition from the native soil microbial community, thus inoculation of field plots cannot be recommended for wheat. [ABSTRACT FROM AUTHOR]

This paper reports the discovery of the earliest evidence of domesticated wheat in the Crimean peninsula from the Ardych-Burun shell midden site, Ukraine. The Ardych-Burun site dates to middle of the 4th millennium CAL B.C. For the first time, the chronology of a Ukrainian Chalcolithic period site has been established through direct radiocarbon dating of cereal grains retrieved from it. This discovery allows for a wider discussion of the chronology and geographical origins of domesticated plant species in Ukraine and the role the Caucasian corridor may have played in the spread of agriculture into eastern Europe. The presence of cereal crops in the southern Crimea enriches our understanding of the subsistence strategies of the coastal population, which was previously linked only with pastoralism, hunting, and the exploitation of marine resources. [ABSTRACT FROM AUTHOR]

The article focuses on a research related to effect of cropping systems and crop residue on productivity and soil properties in organic ecosystem. It mentions that in field trials conducted at Indian Agricultural Research Institute, New Delhi, the effect of rice-wheat (RWVS) and rice-wheat-mungbean (RWMVS) cropping systems on protein yield, energy output and soil properties was analyzed. It informs that RWMCS exhibited higher productivity, energy output and protein yield as compared to RWCS.

The article presents a study on assessing genetic diversity and changes of bread wheat using agronomic traits and microsatellite markers in Qinghai Province, China. It also studied the average value of plant height, effective spikelets per ear and internode length under spike. It also discusses the use of 189 microsatellite markers to examine genetic diversity at a molecular level which showed the average number of alleles, genetic diversity index and allelic richness.

The article presents a study on bi-cropping white lupins with cereals for wholecrop forage in organic farming. It also discusses the crop yield and quality by growing bi-crop of spring white lupin with spring wheat which gave higher dry matter yield across different seed rates for the crop mixture than constituent monoculture. It also discusses the result which shows all lupin/cereal bi-crops to be nutritionally superior to the monocrops in chemical quality for crude protein and ether extracts.

Aflatoxin B1 is a secondary metabolite of some fungi that causes very serious diseases in plants, animals and humans. Both cytological studies and molecular techniques revealed that AFB1 at tested concentrations of 5, 10, 15, 20 and 25 lg/ml exhibits genotoxic effect in wheat plants. Several types of chromosomal aberrations have been detected during meiosis; these aberrations include chromosome stickiness, outside bivalents, bridges, laggards, unequal division and micronuclei. The percentage of total abnormalities increased gradually with the increase of toxin concentration but declined again at the highest concentrations. The highest value (2.9%) of abnormalities, detected during meiosis, was in plants treated with 15 lg/ml AFB1 even so, this value decreased to 1.7% in plants treated with the highest concentration (25 μ/ml) of AFB1. The 5S primer generated amplified DNA fragments of 100, 400, 500, 800 and 900 bp in control plants. However, some of these fragments were missing or faint in a number of AFB1-treated plants. Such considerable alterations in DNA profiles of 5S primed amplicons might indicate the generation of various alterations in the inherent property of the 5S rRNA gene sequence [ABSTRACT FROM AUTHOR]

Abstract: Fifteen-day-old seedlings of two wheat varieties (Side 1 & Gimmiza 7) were randomly separated into three equal groups to investigate the effect of chilling stress on their antioxidant defense system. Moreover, the possible role of polyamines (PAs) pretreatment during alleviating chilling injuries. The first group was kept in a green house at 21/15°C (day/night) and 10: 14h light/dark (−ve control). Second seedlings group were chilled at 5°C for 6 or 9 hours (+ve control). The Seedlings of the third group were divided into three sub-groups and sprayed with 0.5, 1.0 and 2.0mM spermidine (Spd). After 12 hours of polyamine pre-treatments, the seedlings were incubated at 5°C for 6 or 9 hours. At the end of the chilling period, the treated plants were transferred to the pre-experimental conditions in the greenhouse where they recovered for 10 days. Chilling stress induced a significant increase of lipid peroxidation, membrane leakage and hydrogen peroxide level, while Spd treatments resulted in a significant decrease. In addition, endogenous PA level increased in response to chilling stress. Activities of catalase, peroxidase and ascorbate peroxidase declined after the exposure to chilling whereas glutathione and free ascorbate increased. Spd treatments alleviated the injury caused by chilling stress by preventing the decrease in the activity of the antioxidant enzymes. It can be concluded that the stress protection caused by spermidine treatment probably contributes to the enhancement of the activity of the free-radical scavenging systems. Moreover, it was clear that the Sids-1 cultivar was more tolerant to chilling stress than Gemmieza-7cultivar. [Copyright &y& Elsevier]

In pot experiments, the potential of Nostoc muscorum as biofertilizer to promote growth of wheat with different levels of N-fertilizer (ammonium sulphate) was studied. Biofertilization by N. muscorum significantly increased shoot length, leaf area and spike weight of wheat either alone or in combination with N-fertilizer at 50 and 100 Kg N/ha. Combination of biofertilization and N-fertilization, specially at 100 Kg N/ha had more effect on growth of wheat than biofertilization alone. N-fertilization by ammonium sulphate stimulated cyanobacterial abundance in soil after 120 days from cultivation of wheat compared to biofertilization alone and N-fertilization alone. It also stimulated nitrogenase activity In situ, specially at 100 Kg N/ha. Inoculation of wheat with N. muscorum increased total N-yield of shoot system compared with control (non-inoculated plants). However, combination of biofertilization and N-fertilization at 50 and 100 Kg N/ha had more stimulation to N-yield than biofertilization alone or N-fertilization alone. The percentage of nitrogen derived from air induced by combination of biofertilization and N-fertilization at 50 Kg N/ha (36.2 %) in shoot corresponding to 46.3 mg N/pot fixed nitrogen was more than in case of biofertilization alone or N- fertilization, The study recommends the use of N. muscorum as biofertilizer with N-fertilizer at a level of 100 Kg N/ha for wheat production. [ABSTRACT FROM AUTHOR]

Wheat and carrots produced by organic or conventional farming have been investigated by chemical analysis to estimate potential effects on their physiological amino acid status. The samples came from scientific field trials. The methods used are based on precise chemical analysis of substances of the N-metabolism of the plant. The approach for the differentiation and identification of samples of carrots and wheat and its validation are described. It is shown, that the significant differentiation and the correct identification of coded samples of different production conditions were possible. This was achieved by optimizing the precision and accuracy of measurement and by a view of the plant organism, which is oriented on the N-metabolism and its functions. [ABSTRACT FROM AUTHOR]

Systematic changes in wheat and carrots caused by organic or conventional farming were investigated by fluorescence excitation spectroscopy of whole samples. It was possible to identify the farming conditions of coded samples from scientific trials. The method developed and its validation for wheat and carrots is described. [ABSTRACT FROM AUTHOR]

Abstract: Water stress is the major environmental stresses that affect agricultural production worldwide, especially in arid and semi-arid regions. This research investigated the effect of water deficit on wheat cultivars (Al-gaimi, Sindy-1, Sindy-2, and Hab-Ahmar) grown in the Kingdom of Saudi Arabia. Mild (50%) and severe (30%) water deficit regimes were used with a control of 80% soil field capacity. The effect of water stress on growth parameters was investigated including; plant height, leaf area, dry weights of roots, shoots and whole plant. Relative Water Content (RWC) and Water Use Efficiency (WUE) were also determined. The results indicated that the effect of water deficit on growth depended on the combination of water stress regime and wheat cultivars. Mild water deficit affected Sindy-2 and Hab-Ahmar, while Al-gaimi was less affected with neither decrease in root dry weight nor change in dry weight. Under severe stress, growth was decreased in Hab-Ahmar followed by Sindy-2 then Sindy-1, while Al-gaimi was not affected. Al-gaimi and Hab-Ahmar showed a decrease in RWC under the severe stress. Neither Sindy-1 nor Sindy-2 showed change in RWC due to water stress treatments. WUE decreased under severe water deficit in Hab-Ahmar and Sindy-2, but not affected in Sindy-1 and Al-gaimi. [Copyright &y& Elsevier]

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Using experimental data from Nottinghamshire, U.K., the process of stockless organic conversion and the first three years of organic production is examined to analyse the economic legacy of seven stockless organic conversion strategies. Focusing upon the impact of the conversion strategies on the second (bean) and third (oat) organic crops, but also considering the economics of the two-year conversion period and the first organic crop (wheat) the paper provides strategy recommendations to growers considering conversion. Gross margin results indicate that conversion strategies containing fertility building phases provide the highest overall gross margin returns, with the clover-seed - red-clover ryegrass strategy returning an average annual gross margin in the absence of subsidies of £459 ha-1; the second best strategy being the two-year red-clover ryegrass strategy providing an annual average gross margin of £357 ha-1. The influence of the factors that drive economic performance of the bean and oat crops, as measured through the productivity of land, are captured through the estimation of a land quality index (LQI) using regression analysis. The average and marginal economic values of the factors influencing land quality are presented and highlight the importance of weed control in organic production. For a risk-averse grower, the recommended conversion cropping plan based upon the overall average gross margin, the associated agronomic attributes and the value of controlling weeds post-conversion, is the two-year red-clover ryegrass strategy. This strategy recommendation reinforces previous research findings whilst the LQI and associated input-output measures provide an explanation for the underlying factors behind this strategy recommendation. [ABSTRACT FROM AUTHOR]

Assessing soil test maintenance P requirement of a given production system in relation to P supply strategies is of critical importance for judicious and efficient use of inorganic and organic P inputs. Field experiments with soyabean-wheat annual rotation on a Vertisol were conducted for three years to (i) assess the effects of P supplied through different strategies involving fertilizer and cattle manure on crop yield, P uptake and soil test P status, and (ii) determine soil test maintenance P requirement and its relation to P removal by crops. The treatments for the field experiment consisted of a control (no P check) and nine combinations of three annual P rates (P1= 26, P2 = 39 and P3 = 52 kg P ha-1, with the amount of P applied to soyabean and wheat being in the ratio of 1.6:1.0) and three P supply strategies (PSS-I = fertilizer-P for both soyabean and wheat, PSS-II = cattle manure-P for soyabean and fertilizer-P for wheat, and PSS-III = cattle manure-P + fertilizer-P on 1:1 P basis for soyabean and fertilizer-P for wheat). The soyabean and wheat crops responded significantly to P application under all the P supply strategies. The crop yield increases due to P input were, however, strikingly larger under PSS-II and PSS-III than under PSS-l. Agronomic efficiency of P (yield increment per unit of P applied) also indicated the superiority of the PSS-III and PSS-ll over the PSS-I. The P uptake by crops in soyabean-wheat rotation increased significantly and linearly with increasing P rate under all the P supply strategies. During three cycles of annual soyabean-wheat rotation, the soil test P in the plot receiving no P (P0 control) declined from the initial 5.84 to 2.40 mg kg-1, while it showed a marked build-up with P application particularly at higher rates. The annual soil test maintenance P requirement (STMPR) was lower by 27-33% under PSS-II (26.3 kg P ha-1) and PSS-Ill (24.1 kg P ha-1) than under PSS-I (36.1 kg P ha-1). Despite these differences in STMPR, the crop yields achievable at STMPR were interestingly more or less similar across all the P supply strategies. In terms of P removal by crops, the STMPR equalled or slightly exceeded the P removal by crops under the PSS-III and PSS-II, while it was 1.4 times the removal under PSS-I. Therefore, the use of manure-P as a component of P supply strategies can help reduce the amount of P required to maintain soil P fertility and hence increase P utilization efficiency. [ABSTRACT FROM AUTHOR]

Considerable changes are observed in the abundance of cultivated plants in the northern Alpine foreland between 3500 and 2400 cal. BC. The importance of tetraploid naked wheat (Triticum durum Desf./turgidum L.) and opium poppy (Papaver somniferum L.) declines whereas that of glume wheat (mainly emmer, Triticum dicoccum Schübl.) and flax (Linum usitatissimum L.) increases progressively. The hypothesis presented here is that these developments are mainly due to changing cultural spheres of influence. Many of these changes are, however, not fully traceable due to the very heterogeneous and, in part, very poor state of research in this area. [ABSTRACT FROM AUTHOR]

A greenhouse experiment was conducted to reveal whether it is possible to favour winter wheat by reducing the seed rate of spring barley in a relay-cropping system. Since crops sown at low seed rates may be less tolerant to high weed pressure the study also included weed competition. The experimental design was additive, the density of winter wheat being held constant while spring barley density was increased from 167 to 544 plants m-2. At four successive harvest times, the growth of the crops and weed was followed until barley maturity. The wheat plants remained at a vegetative stage during the study period. Seed rate of barley influenced both barley and wheat biomass less in the presence of weed than in the absence. Weed competition reduced wheat biomass significantly only at the lowest seed rate. The presence of weed also reduced barley biomass. The reduction decreased with increased seed rate. In weed-free stands, seed rate influenced barley biomass less and had no significant effect on barley grain yield, which was on average 772 g m-2. By contrast, in the presence of weed, barley grain yield increased from 242 to 646 g m-2 with increased plant density. The relative weight decrease per individual plant in response to barley seed rate and weed competition did not differ between wheat and barley, suggesting that wheat and barley responded equally to treatments. It is concluded that wheat performance is favoured by reduced barley seed rate. However, low seed rate will reduce barley grain yield if the weed pressure is high, while wheat may be less sensitive to the weed situation. [ABSTRACT FROM AUTHOR]

In response to the Curry Report, the U.K. Government's Organic Action Plan aims to increase the area of organic production. In addition, Common Agricultural Policy (CAP) reform will provide an incentive for farmers to become more market-led and examine alternative production possibilities. However, the two-year conversion period represents a barrier to organic production. In a stockless system the typical conversion strategy is a red clover (Trifolium pratense L.) -- ryegrass (Lolium sp. L.) green manure, attracting both Area Aid Payments (AAP) and Organic Farming Scheme (OFS) subsidies. Six alternative strategies to this green manure were tested in a replicated randomized block field experiment. Gross margin analysis of the conversion strategies in the presence and absence of AAP and OFS payments are presented. Sensitivity analysis of crop yields and prices indicates the robustness of the gross margin analysis. Where contracts to supply red clover seed can be obtained, growing clover seed in year 1 of conversion followed by a clover green manure in year 2 provides the highest mean annual gross margin, measured over the two-year conversion period and the first organic wheat (Triticum aestivum L.) crop. In the absence of a clover seed contract the two-year red clover-ryegrass green manure provides the highest mean annual gross margin, and is therefore likely to remain a popular conversion strategy. This holds given the decoupling (absence) of AAPs due the enhanced yield of the first organic wheat crop compared with more exploitative conversion strategies. Other strategies that may be appropriate include oats (Avena sativa L.) followed by beans (Vicia faba L.), however a change in policy on acceptable organic conversion crops would be required to enable this strategy to be considered. [ABSTRACT FROM AUTHOR]

A brief account of interest in dielectric properties of agricultural materials is presented, and some examples of dielectric spectroscopy applied to agricultural problems are discussed. Included are wide frequency range (250 Hz to 12 GHz) permittivity, or dielectric properties, measurements on adult rice weevils and hard red winter wheat, for the purpose of assessing selective dielectric heating of the insects, and broadband (200 MHz to 20 GHz) permittivity measurements on tissues of fresh fruits and vegetables. Similar measurements are shown for tree-ripened peaches, which were obtained to assess possibilities for a permittivity-based maturity index. Broadband (10 MHz to 1.8 GHz) permittivity measurements are shown for several fruits and vegetables as a function of temperature from 5 to 95 °C. Measurements over the same frequency range and similar temperature ranges are presented for two other food products, whey protein gel and apple juice. A few comments are offered on likely future dielectric spectroscopy applications in agriculture. [ABSTRACT FROM AUTHOR]

Three outdoor pot experiments with three wheat cultivars and Lolium multiflorum were conducted at La Plata National University (Argentina), where the effects of shoot and root competition were separated using aerial partitions. Root competition (RCj for both shoot dry matter yield (SDM) and grain yield was higher (p < 0.05) than shoot competition (SC). Cv. P.I.Super was most affected by SC while CVS. K.Cacique and B.Charma were least affected. Crop competition caused a highly significant reduction of weed variables. RC had a greater effect on both weed SDM and weed seed yield than did SC. Cvs. B.Charrua and K.Cacique registered a higher photosynthetically active radiation interception (PAR) than cv. P.I.Super and L. multiflorum in SC treatment, but cv. P.I.Super intercepted more PAR than L. multiflorum and cvs. B.Charrua and K.Cacique in RC treatment. The resources complementarity for grain yield was obtained by means of relative yield total (RYT). There was resources complementarity when wheat and weed were in SC, but not in RC and full competition (FC), showing that the species were in full competition, despite the high nitrogen availability throughout the crop growing cycle. Cvs. B.Charrua and K.Cacique were more aggressive than the weed, while cv. P.I.Super was less aggressive than the weed in the SC treatment. Conversely, in both the RC and FC treatments, higher aggressivity than wheat cvs. was shown by the weed. This result could be ascribed to the lower shoot/root ratio and the higher nitrogen uptake of L. multiflorum. Despite the high availability of nitrogen, the results demonstrate that competition was mainly for soil nutrients, and wheat cvs. with a higher competitive ability in above-ground competition may have no competitive advantage when RC occurs. Because the experimental technique in pots does not reflect field conditions, caution is needed in extrapolating the results to a field situation. [ABSTRACT FROM AUTHOR]