• Authors:
    • Naeem, M.
    • Khan, F.
    • Ahmad, W.
  • Source: Soil and Environment
  • Volume: 29
  • Issue: 1
  • Year: 2010
  • Summary: This study was undertaken as a part of soil fertility management of eroded soils in NWFP, Pakistan. The study was started in summer 2006 and continued for four consecutive crop seasons till winter 2007, in District Swabi, NWFP, Pakistan. Soil fertility status of the experimental site was determined before the start of the experiment. The experiment was laid out in a factorial split plot design using two factors viz cropping patterns and fertilizer treatments. The cropping patterns included maize-wheat-maize rotation, maize-lentil-maize rotation and maize-wheat+lentil intercrop-maize rotation and these were kept in main plots whereas the fertilizer treatments included control, 50% NP, 100% NPK and 20 t ha -1 farmyard manure integrated with 50% N and 100% PK as mineral fertilizers which were placed in sub plots. Fertilizers were applied for four seasons continuously. At the end of winter 2007, soil samples from two depths (0-20 cm and 20-40 cm) were collected from each plot and analyzed for microbial biomass carbon (MBC) at day 3, day 6 and day 10 incubation periods, total nitrogen (TN), microbial biomass nitrogen (MBN), and mineralizable nitrogen (MN). Results showed significant improvement in organic fertility of soil with fertilizer addition and cropping patterns. Combined application of organic and inorganic fertilizers (20 t ha -1 farmyard manure integrated with 50% N and 100% PK) showed 55, 25, 18 and 61% increase in total N, MBN, MN, and MBC after 10 days incubation period over the control, respectively, in the surface soil whilst 100% NPK showed 44, 15, 6 and 45% improvement over the control treatment for the same parameters in surface soil. Data further showed 43, 23, 19 and 60% increase in the corresponding microbial parameters in combined organic and inorganic fertilizer treatment over the control treatment in sub soil whilst 100% NPK showed 39, 20, 10 and 54% increase in TN, MBN, MN and MBC over the control in sub soil. The cropping patterns having cereal-legume rotation also improved organic soil fertility and showed 27 and 13% more total N and MBC after 10 days incubation period over the cereal-cereal rotation respectively and the improvement in MBN and MN in cereal-legume rotation over cereal-cereal rotation was non significant in surface soil. In the sub-surface soil cereal-legume rotation improved TN, MBN, MN and MBC by 9, 6, 8 and 28% over the cereal-cereal rotation. It was concluded that there is sufficient potential to improve soil organic fertility in Pirsabak soil series, the restoration of which on sustained basis would require at least 50% N from the organic sources. Moreover legumes must be included in the traditional cereal-cereal cropping pattern to further improve the N input and organic fertility of these soils.
  • Authors:
    • Hussain, F.
    • Akhter, J.
    • Ashraf, M.
    • Iqbal, Z.
    • Yaqub, M.
    • Akhtar, M.
  • Source: Pakistan Journal of Botany
  • Volume: 42
  • Issue: 6
  • Year: 2010
  • Summary: Soil fertility and organic matter in our soils are on decline. Legume intercropping and manuring are important measures to sustain fertility and enhance productivity of soil. Four wheat cultivars Inqlab-91, WL-886, 1076 & 41 grown in field either as mono crop or intercropped with chickpea (CM 88) were evaluated with respect to yield, nutrient (N & P) uptake, compatibility and profitability. Prior to establishment of experiment, soil was enriched by green manuring of vegetative biomass of legume cereal for the last two years to raise organic matter/nutrients contents sufficienctly for growing a crop without mineral fertilizer addition. In monoculture, wheat cultivar Inqlab-91 produced the maximum grain (3294 kg ha -1) than other wheat lines (WL). In intercropping system, one hactare of land produced a maximum grain yield of WL-1076 (2456 kg) along with additional chickpea grain yield (1302 kg) while an other association produced maximum grain yield of chickpea (1795 kg) along with additional wheat yield (2144 kg by Inqlab-91). Cumulative grain value (Rs. ha -1) in intercropping culture was two times higher compared to that of wheat mono cropping. Associated crops accumulated significantly higher N in their biomass with a maximum of 87 kg ha -1 (by Inqlab+chickpea), compared to a maximum of 58 kg ha -1 by wheat (Inqlab-91) as mono culture. Phosphorus uptake by associated crops was also higher compared to wheat grown alone. The results clearly suggested superiority of wheat-chickpea co-cropping over wheat monoculture in terms of enhanced nutrient utilization, crop yield and farm income.
  • Authors:
    • Hinsinger, P.
    • Souche, G.
    • Justes, E.
    • Colomb, B.
    • Betencourt, E.
  • Source: Proceedings of the 19th World Congress of Soil Science: Soil solutions for a changing world
  • Year: 2010
  • Summary: We need to aim for ecological intensification of agroecosystems, in order to cover an increasing global food demand while decreasing agricultural inputs such as fertilisers is required to maintain ecosystem services. Increasing the efficiency of nutrients to plants while decreasing nutrient inputs means that better exploration and exploitation of soil resources must be achieved in agroecosystems. This paper focusses on intercropping, which proved efficient to increase agroecosystem productivity, via better exploitation of soil resources. We studied the underlying processes of acquisition of soil phosphorus (P) by plants in cereal/legume agroecosystems, with a particular focus on rhizosphere processes. The working hypothesis is that the two intercropped species may access different P pools, the legume being responsible for greater changes in P availability in the rhizosphere, as a consequence of root-induced acidification resulting from nitrogen fixation. We sampled the rhizosphere of field-grown plants at two stages of growth of durum wheat and pea/faba bean along a gradient of soil P availability. Available P increased in the rhizosphere, especially for the legumes, and more so when intercropped. This was possibly due to the increased proportion of nitrogen fixation in the intercropped legumes, thereby resulting in inter-species facilitation for P acquisition.
  • Authors:
    • Molnar, L. J.
    • Blackshaw, R. E.
    • Moyer, J. R.
  • Source: Canadian Journal of Plant Science
  • Volume: 90
  • Issue: 4
  • Year: 2010
  • Summary: Farmers on the Canadian prairies are interested in including legume cover crops in their cropping systems to reduce fertilizer inputs and improve farm sustainability. A field study was conducted to determine the merits of establishing alfalfa ( Medicago sativa L.), red clover ( Trifolium pratense L.) or Austrian winter pea ( Pisum sativum L.) cover crops in fall or in spring with winter wheat ( Triticum aestivum L.). Spring-planted legumes emerged well within the winter wheat crop, but their growth was limited under these semi-arid conditions. Fall-planted red clover had low plant densities following winter in two of three experiments and fall-planted winter pea reduced winter wheat yield by 23 to 37% compared with the no cover crop control. In contrast, fall-planted alfalfa exhibited good winterhardiness, provided some weed suppression without reducing winter wheat yield, caused only a slight reduction in soil water content, and contributed an extra 18 to 20 kg ha -1 of available soil N at the time of seeding the following spring crop. Additionally, fall-planted alfalfa increased the yield of succeeding canola ( Brassica napus L.) in unfertilized plots in two of three experiments. Further research is warranted to better understand the agronomic and economic benefits of alfalfa-winter wheat intercrops under a wider range of environmental conditions.
  • Authors:
    • Sarma, K. K.
    • Debnath, M. C.
    • Borah, B. K.
    • Das, B.
  • Source: Insect Environment
  • Volume: 15
  • Issue: 4
  • Year: 2010
  • Summary: Gram pod borer, Helicoverpa armigera Hubner is the most important pest on chickpea. The present study was undertaken to study the effect of different intercrops on the incidence of gram pod borer on chickpea. The experiment was conducted at Regional Agricultural Research Station, Shillongani, Nagaon (North-east India) in rabi season, 2007-2008. Seven crops were used as intercrops viz., linseed, marigold, wheat, mustard, fennel, coriander and garlic. The chickpea variety, PantG-186 was sown in 5 x 4m size plots and the ratio with intercrop was 4:1, except the sole crop which was used as check. Each intercrop was replicated thrice in RBD. Recommended package of practices were followed. For observation of larvae, ten plants were selected randomly from each plot and their count was recorded weekly. Similarly, for pod damage, ten plants randomly selected were uprooted at harvest and per cent pod damage was assessed by counting all the pods.
  • Authors:
    • Radicetti, E.
    • Mancinelli, R.
    • Campiglia, E.
    • Caporali, F.
  • Source: Crop Protection
  • Volume: 29
  • Issue: 4
  • Year: 2010
  • Summary: Cover crops and mulches are a suitable choice for sustainable agriculture because they improve weed control and crop performance. The aim of this research was to investigate weed control and nitrogen supply by using different winter cover crop species which were converted into mulches in spring. We carried out a 2-year field experiment where a tomato crop was transplanted into four different types of mulches coming from winter cover crops [(hairy vetch ( Vicia villosa Roth.), subclover ( Trifolium subterraneum L.), oat ( Avena sativa L.), and a mixture of hairy vetch/oat)] and in conventional treatment (tilled soil without mulch). The mixture of hairy vetch/oat cover crop produced the highest aboveground biomass (7.9 t ha -1 of DM), while the hairy vetch accumulated the highest N in the aboveground biomass (258 kg N ha -1). The oat cover crop was the most effective cover crop for suppressing weeds (on average -93% of weed aboveground biomass compared to other cover crops). After mowing the cover crop aboveground biomass was placed in strips as dead mulch into which the tomato was transplanted in paired rows. Weed density and total weed aboveground biomass were assessed at 15 and 30 days after tomato transplanting to evaluate the effect of mulches on weed control. All mulches suppressed weeds in density and aboveground biomass compared to the conventional system (on average -80% and -35%, respectively). The oat was the best mulch for weed control but also had a negative effect on the marketable tomato yield (-15% compared to the conventional treatment). Amaranthus retroflexus L. and Chenopodium album L. were typical weeds associated with the conventional treatment while a more heterogeneous weed composition was found in mulched tomato. Legume mulches, in particular hairy vetch, gave the best marketable tomato yield 28% higher than the conventional system both with and without nitrogen fertilization. This research shows that winter cover crops converted into dead mulch in spring could be used successfully in integrated weed management programs to reduce weed infestation in tomato crops.
  • Authors:
    • Lithourgidis, A.
    • Dordas, C.
  • Source: Crop Science
  • Volume: 50
  • Issue: 5
  • Year: 2010
  • Summary: Annual cool-season grain legumes like faba bean ( Vicia faba L.) grown in mixtures with winter cereals such as wheat ( Triticum aestivum L.), barley ( Hordeum vulgare L.), or rye ( Secale cereale L.) may offer advantages over cereal-alone crops grown for forage production. A 2-yr field study was conducted to evaluate the effects of intercropping faba bean with each of the above cereals in three seeding ratios (i.e., 75:25, 50:50, and 75:25) on growth rate, plant height, chlorophyll content, forage yield, and N uptake. Growth rate of faba bean and cereals was lower in the mixtures than in the monocultures, especially in the faba bean-barley mixtures because of the strong competitive ability of barley. Chlorophyll content was lower in faba bean compared with the cereals, and there was no difference among seeding ratios. Plant height of faba bean was higher in the intercrops compared with its monocrop at 3 wk after tillering (WAT), whereas at 6 WAT, the trend was different since faba bean plants in the monocrop were higher than in the intercrops. Rye monocrop and rye-faba bean intercrops provided the greatest forage yield. Although the three intercrops of faba bean with rye had lower crude protein (CP) content than the faba bean monocrop, they provided the highest CP yields per hectare because of their higher forage yield than the faba bean monocrop.
  • Authors:
    • Crozat, Y.
    • Pineau, S.
    • Corre-Hellou, G.
    • Naudin, C.
    • Jeuffroy, M. H.
  • Source: Field Crops Research
  • Volume: 119
  • Issue: 1
  • Year: 2010
  • Summary: Cereal-legume intercrops are a promising way to combine high productivity and several ecological benefits in temperate agro-ecosystems. However, the proportion of each species in the mixture at harvest is highly variable. The aim of this study was to test whether the timing of small application of N fertilizer is an effective way of influencing the dynamic interactions between species during crop growth and affecting the percentage of each species in the biomass of the mixture without greatly disturbing N 2 fixation. The influence of timing of nitrogen fertilization in pea-wheat intercrops was studied as regards (i) the dynamics of crop growth, (ii) nitrogen acquisition of each species, (iii) the inhibition and recovery of symbiotic N 2 fixation (SNF) after N application and (iv) final performance (yield, % of wheat, grain protein content). This was assessed in winter pea-wheat ( Pisum sativum L.- Triticum aestivum L.) intercrops in 2007 and 2008 at two locations in France. Whatever the stage of application, N fertilizer tended to increase wheat growth and to decrease pea growth. N fertilization (applied once at different dates from tillering to the end of stem elongation) delayed the decrease in the contribution of wheat to total biomass and maintained the competitive ability of wheat over pea for longer than in unfertilized intercrops. N acquisition dynamics and N sharing between the two species were modified by N fertilization and its timing. Crop conditions at the time of N application (growth and phenology of each species, and their proportions in the intercrop biomass) greatly influenced intercrop response to N fertilization. Partitioning between species of soil and fertilizer N was correlated with the proportion of wheat in the total intercrop biomass observed at the date of N application. Short-term inhibition of nitrates on SNF was shown during the few days after N application, whatever its date. SNF recovery after N applications was observed only until pea flowering, but was prematurely stopped by N fertilization after this stage. The effect of N fertilization on the amount of fixed N 2 at harvest was correlated with pea biomass. N fertilization affects N 2 fixation mainly by affecting crop growth rather than %Ndfa in pea-wheat intercrops. In conclusion, N fertilization could be used as a tool to enhance the contribution of wheat in the intercrop biomass but may reduce the amount of fixed N 2 in the intercrop by decreasing pea biomass.
  • Authors:
    • Ponizil, A.
    • Henriksen, B.
    • Pozdisek, J.
    • Hunady, I.
    • Loes, A. K.
  • Source: Vyzkum v Chovu Skotu
  • Volume: 52
  • Issue: 3
  • Year: 2010
  • Summary: Controlled field trials with legume-cereal mixtures and monocultures were conducted on five organic farms in CR, to determine the suitability for feeding ruminants. Mixtures of 60% peas to 40% cereals (wheat and barley) were compared with peas, wheat, and barley monocultures. The obtained results are useful to assess how mixtures may be included in animal feed rations. For feeding beef cattle, it is most beneficial to harvest green matter in the BBCH 79 growth phase (green ripeness), which is characterized by a higher protein and energy content and a lower fiber content. Advantageous crop for beef cattle appeared to be the mixture with peas and barley, because the crude protein and NEL contents come the closest to the requirements for a balanced state between breakdown and synthesis in the rumen (CP 130 g kg -1, NEL 5.9 MJ kg -1 DM). The results support that legume-cereal intercropping is a feasible technology to produce high quality feed on organic farms, which may provide animals with good health, and potential to utilize their genetic capacity for growth and production.
  • Authors:
    • Biradar, D. P.
    • Rathod, P. S.
    • Patil, V. C.
  • Source: Journal of Medicinal and Aromatic Plant Sciences
  • Volume: 32
  • Issue: 4
  • Year: 2010
  • Summary: A field experiment was conducted at Regional Agricultural Research Station, Bijapur on medium deep black soil during rabi seasons of 2004 and 2005 to study the influence of different rabi intercrops on growth and productivity of senna. The treatment consists of five rabi crops (chickpea, safflower, linseed, mustard and wheat) and senna in sole stand as well as intercropping system and safflower+chickpea (2:4) intercropping system as a check. The sole crop of senna recorded significantly better growth and growth parameters as compared to intercropped senna. The leaf and pod yield of senna also followed the same trend as that of growth and growth parameters with different rabi intercrops. Growing of senna with safflower adversely reduced the growth and growth parameters, leaf and pod yield as compared to chickpea, linseed, mustard and wheat.