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Productivity of FieldPea (Pisumsativum L.) and Spring Oat (Avena sativa L.) Grown as Sole and Intercrops Under Different Nitrogen Levels  [cached]
Chengchou Han,Christopher Borman,Dori Osantowski,Jeremy Wagnitz
Journal of Agricultural Science , 2012, DOI: 10.5539/jas.v4n11p136
Abstract: Intercropping cereal grains and legumes has potential as an alternative cool-season forage cropin low-input farming systems. The objectives of this study were to quantify the effects of density, species proportion and nitrogen (N) supply on the biomass accumulation of field pea and spring oat grown as sole or intercrops. Greenhouse experiments were conducted using an additive series experimental design. Treatments included threefertilizer Nrates and 20 density/proportion combinationsin a randomized complete block with four replications. Sole plant densities included 2, 3, 4, 5 plants of each species pot-1 (16 cm in diameter, 16 cm in height). The species ratios per pot for the intercrop included 1:1, 1:2, 1:3, 1:4, 2:2, 2:3, and 3:5 and their reciprocals. Nitrogentreatments included urea at 0, 0.2, or 1.0 g N pot-1in a split application. Plants were harvested and oven dried to constant weight at 46 days after planting. As density increased, sole cropped oat and fieldpea biomass increased. In the intercrop, oat showed greater biomass accumulation at higher N levels, whereas field pea biomass was reduced at the highest N level. In both sole and intercrop, oat was more sensitive to intraspecific competition than field pea. Niche differentiation was only observed at the highest N level. At higher N and lower total density, mixtures yielded more than monocultures, indicating that intercropping of field pea and spring oat may be beneficial. Results from this study can aid in future field research to determine optimum density for each species and N rates to be applied in field pea-oat intercropping systems.
Effect of Legume Intercrops and Nitrogen Levels on the Yield Performance of Maize  [PDF]
Nazim Hussain,Imran Haider Shamsi,Sherin Khan,Habib Akbar
Asian Journal of Plant Sciences , 2003,
Abstract: This experiment was conducted to study the beneficial effect of legumes and inorganic quantities of N on maize crop. Different levels of nitrogen i.e. 0, 40, 80 and 120 kg ha-1 were used. Besides maize alone, intercrops were; maize+mungbean, maize+pigeon pea and maize+janter. Maize @ 40, mungbean 20, pigeon pea 50 and janter at 25 kg ha-1 were used respectively. Maximum seedlings emerged m ̄2 (40.20) was obtained at 120 kg N ha-1 in maize alone. Maximum days (61.7) to earing were taken by maize intercropped with janter. Maximum days (67.50) to silking were taken by maize+janter intercrop at 0 kg N ha-1. Maximum plant height (165.50 cm) was observed in maize alone at 120 kg N ha-1. Maximum cob length (12.55 cm) was noticed in maize and mungbean intercrop under 40 kg N ha-1. Maximum biological yield (28429.63 kg ha ha-1) was obtained from maize alone by 40 kg N ha-1. Maximum number of grains cob-1 (309) was obtained from maize and pigeon pea intercropping at 120 kg N ha-1. For maximum yield potential maize alone and maize+mungbean intercropping was at par statistically at 80 and 40 kg N ha-1 by giving 3463 and 3444 kg ha-1 yield, respectively. Overall legume intercrop was superior by decreasing less yield of maize crop in addition to legume seed yield and N cost minimization.
Relative Aerial Biomass Yield of Intercroped Alfalfa with Winter Forage Cereals
Pereyra,Telmo; Pagliaricci,Héctor; Ohanian,Alfredo;
Chilean journal of agricultural research , 2008, DOI: 10.4067/S0718-58392008000300005
Abstract: in the tropical regions of the world, intercropping is mostly associated with food grain production, whereas it is receiving increased attention in temperate regions as a means of efficient forage production. the aim of this work was to determine the relative yield of aerial biomass in alfalfa or lucerne (medicago sativa l.) and winter forage cereals intercrops. these were done in eight systems resulting from the combination of species sown at different dates. the biomass was measured in three situations: alfalfa and cereal sole-crop and alfalfa-cereal intercrops, the relative biomass yields were calculated by the relative yield index (ryi). the field experiment was conducted as a bifactorial array in a randomized complete block design of two replicates. the alfalfa-cereal intercrops provided ryi values ranging from 0.71 to 0.83. this showed that it is possible to produce, in the same area, between 71 and 83% of the biomass that both crops would produce in separate ones.
Competition and Facilitation in Hairy Vetch-Barley Intercrops
Giacomo Tosti,Paolo Benincasa,Marcello Guiducci
Italian Journal of Agronomy , 2010, DOI: 10.4081/ija.2010.239
Abstract: Intercrops between legumes and non-legumes are widely used for fodder production and as cover crops, but little quantitative data are available on competition between species in the mixture. The objective of the present study was to assess the interaction between hairy vetch (Vicia villosa Roth.) and barley (Hordeum vulgare L.) grown as pure crops or intercrops with different proportions of seed rates at sowing. A 4-year field study was conducted using hairy vetch and barley as pure stands at full sowing density and as intercrops at different proportions of their own full seed rate according to the replacement principle. Interaction between species was evaluated on the basis of Land Equivalent Ratio (LER), Relative Neighbour Effect (RNE) and Aggressivity (A) calculated on biomass and nitrogen (N) accumulation. The N accumulation of the mixed crops increased linearly with the legume proportion in the mixture. The mixtures were more efficient than the pure crops in terms of N use (LER > 1). Partial LER values indicated that the barley component benefited from the presence of the legume, while the hairy vetch partial LER decreased with increasing barley proportion in the mixture. The competitive response in terms of biomass accumulation was high for both species when their density in the mixture was high. Concerning N accumulation, barley benefited from an asymmetric interspecific facilitation while the vetch behaviour was similar to that observed for biomass accumulation. Barley dominance progressively increased reaching a maximum just before the last sampling date. At the last sampling date the competitive ability of hairy vetch showed a considerable increase in all mixtures (A ≈ 0). These findings indicate that the use of mixtures between hairy vetch and barley allows an increase in the use efficiency of N resource with respect to pure crops. Barley is the dominant component of the mixture and the hairy vetch is able to cope with the cereal competitive effect only at the end of the shooting phase of barley. Moreover when the soil N supply is high, the recovering ability of the vetch in the mixture could be strongly reduced. In such conditions, the proportion of legumes at sowing should be increased in order to counteract barley dominance and allow a late recovery of the legume component.
Effects of Shade on Nitrogen and Phosphorus Acquisition in Cereal-Legume Intercropping Systems  [PDF]
Meighen Whitehead,Marney E. Isaac
Agriculture , 2012, DOI: 10.3390/agriculture2010012
Abstract: With increasing economic and environmental costs associated with fertilizer use, the need for low-input agroecological systems is on the rise. It is well documented that intercropping legumes can increase the supply of nutrients, through N 2-fixation and P mobilization. Concurrently, the integration of trees in the agricultural landscape shows increasing evidence of nutrient inputs through efficient biogeochemical cycles. However, little is known about the effects shade has on legume-crop performance. This research aims to determine whether intercropping of the legumes soybean ( Glycine max L . Merr.) and alfalfa ( Medicago sativa) with wheat ( Triticum turgidum durum) is beneficial for performance, particularly under shady conditions associated with tree-based intercropping. Test species were cultivated in hydroponics with a broad nutrient solution and steady state addition of N for 3 weeks. Individual plants were transferred to rhizoboxes with a 2 mm zone of soil for 16 days under (i) full sun or (ii) shade to mimic light levels at the tree-crop interface. Under monocropping, shading was found to significantly decrease wheat biomass. Intercropping wheat with alfalfa under full sun had no negative effect on growth but did increase wheat P uptake as compared to monocropped wheat. In contrast, intercropping wheat with soybean under full sun decreased wheat biomass, suggesting competition. However, under shade, this competitive effect was mitigated, as wheat exhibited similar biomass and higher N and P shoot concentration when associated with soybean as compared to monocropped wheat under lower light levels. This effect may be attributed to reduced biomass of soybean combined with higher soybean N 2-fixation under shade. Legume-based intercrops may increase nutrient supply and growth but these beneficial effects will be dependent on matching species selection to light levels under tree-based intercropping.
Comparison of nutritive values of grasses and legume species using forage quality index
Fazel Amiri,Abdul Rashid b. Mohamed Shariff
Songklanakarin Journal of Science and Technology , 2012,
Abstract: Understanding forage quality and the factors that affect its constituents will help improve livestock production bymaking decisions that optimize forage nutritive value and intake. This investigation was conducted in Zagros semi-aridrangeland center, Iran to determine forage quality of several grass and legume species. Samples were collected at earlybloom, from 5 m long and 0.10 m wide strips at a cutting height of 0.05 m. The samples were weighed for dry matter yield andnutritive value measurements. Samples were dried and analyzed in the laboratory by standard methods to determine thefollowing parameters: nitrogen, crude protein (CP), ash, ether extract, neutral detergent fiber (NDF), acid detergent fiber(ADF), digestible energy, dry matter digestibility (DMD), metabolizable energy, dry matter intake (DMI) and Relative ForageQuality Index (RFQi). Standard ANOVA procedures were used to analyze the data. Quality of forage species was classifiedbased on RFQi similarity in Mosaic version 3.01 and PC-ORD environment software. There was a positive correlationbetween CP, DMD, DMI and RFQi for all species, and also a negative correlation between ADF, CP and RFQi. The results ofstatistical analysis show that, forage quality of species (Leguminoseae and Gramineae) were significantly different (P<0.05).Species from gramineae showed significantly (P<0.05) higher ADF and NDF than leguminoseae species. At the stage ofsampling, gramineae had lower RFQi than the legume family. The results of study showed the decision to practice grazing ormake hay or how to select the best hay available should be based on forage quality. A forage analysis is therefore importantto evaluate the nutritive value of the forage to be grazed or hay to be purchased or marketed. Knowing what affects foragequality will also help in making appropriate selection of forages and supplements that will match livestock requirements andresult in economically optimum livestock performance.
Yield and Uptake of Phosphorus by Wheat and Canola Grown after Two Years of Forage Legume and Annual Crops  [PDF]
Rehemuti Miheguli, Jeff J. Schoenau, Paul G. Jefferson
American Journal of Plant Sciences (AJPS) , 2018, DOI: 10.4236/ajps.2018.99132
Abstract: Annual legumes have been shown to enhance the growth and phosphorus (P) uptake by following rotational crops. However, there is lack of information on the effect of perennial forage legumes included in rotation for a short duration on yield and P uptake of crops like wheat (Triticum aestivum L.) and canola (Brassica napus L.) grown after the forage legume. A field study was conducted in four soil zones of Saskatchewan, Canada to assess: 1) the effect of two years of forage legume versus annual cereal, oilseed and grain legume on yield and P uptake of wheat and canola grown in the two subsequent years and 2) the effect of the complete four-year rotation on soil P dynamics and P balance. Four different crop sequences (alfalfa-alfalfa, red clover-red clover, barley-pea and barley-flax) employed over the first two years of crop rotation were compared as treatments followed by wheat and canola. Wheat grain yield was improved 32% - 60% by alfalfa (Medicago sativa L.) and red clover (Trifolium pretense L.) rotations at three of the four sites (P = 0.008, P = 0.001, P < 0.0001) compared to annual grains, while grain P uptake was enhanced 38% - 43% by red clover and alfalfa rotation at two sites (P = 0.013, P =
Progress in the Biotechnology of Legume Forage Plants
豆科牧草基因工程研究进展

ZHANG Zhen-xia,FU Yi-kun,CHUCheng-cai,
张振霞
,符义坤,储成才

遗传 , 2002,
Abstract: As important forage crops,legume forage plants can play an important role in improving natural environment, ma-intenins water and soil. With development of molecular biology and improvement of plant transformation techniques, molecular breeding of legume forage plants by biotechnology is possible. This review summarized recent progress on improvement of several forage crops,including improvement of nutrient quality,increase of biomass,enhancement of the assimilation and efficient absorb of nutrient element,and enhancement of abiotic and biotic stress resistance.
Effect of Legume - Grass Mixture on Forage Yield and Quality in the Pothwar Plateau of Pakistan  [PDF]
Parveen,Parveen, S.,Qamar, I.A.,Ali, A.
Journal of Biological Sciences , 2001,
Abstract: Appropriate ratio of rice bean and blue panic were studied to maximize forage yield and to assess crude protein content. There were five planting ratios consisted of sole rice bean legume, 75 % rice bean and 25% blue panic, 50% rice bean and 50% blue panic, 25 % rice bean and 75% blue panic and 100% blue panic grass. The experiment was conducted without fertilizer or irrigation. The mixtures were in general high yielding than any of the sole crops while, 75 % rice bean and 25% blue panic produced the highest dry matter yield of 7 t ha 1. Crude protein content in the legume component was relatively higher and decreased with the increase of grass ratio.
Intercropping of Cereals and Legumes for Forage Production  [cached]
Hamdollah ESKANDARI,Ahmad GHANBARI,Abdollah JAVANMARD
Notulae Scientia Biologicae , 2009,
Abstract: Cereals are high important in feeding ruminant animals for their high dry matter production and low cost. However, cereals forage is poor in protein content which shows their low quality and nutritive value. Regarding to high feed costs of protein supplementations, legumes can be used in livestock nutrition for their high protein content and, thus, providing cost saving. Since legumes have low dry matter yield, acceptable forage yield and quality can obtained from intercropping of cereals and legumes compared with their sole crops. In this paper, forage quality indicators and different factors affecting forage quality are discussed. Forage production and quality of different cereals-legumes intercropping are also reviewed, where; different legumes had different effect on forage quality when intercropped with specific cereal. Regarding to forage quality and quantity, different cereals also led to different production of forage. A number of factors which must be noticified in selecting cereal-legume intercropping compositions, especially for forage production, were considered.
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