• Authors:
    • Zhou, X.
    • Wu, F.
  • Source: Acta Pedologica Sinica
  • Volume: 46
  • Issue: 5
  • Year: 2009
  • Summary: Plenty of reports about effects of intercropping improving yield and reducing disease incidence are available, but little was reported about the mechanism of the effects. RAPD and T-RFLP methods were used to study effects of intercropping of cucumber with wheat, vicia villosa and clover, individually, on cucumber disease indexes, cucumber rhizosphere soil microbial community diversity and yield. Results showed that intercropping of cucumber with wheat and vicia villosa increased soil microbial community diversity in cucumber rhizosphere, and the effect of the latter was the most prominent. All intercropping modes increased cucumber yield significantly ( p
  • Authors:
    • Sun, J.
    • Chen, L.
    • Cheng, D.
    • Liu, Y.
    • Chen, J.
    • Zhou, H.
  • Source: Acta Phytophylacica Sinica
  • Volume: 36
  • Issue: 2
  • Year: 2009
  • Summary: To study the ecological effect of genetic diversity of wheat cultivars on Sitobion avenae, the population dynamics of S. avenae and its natural enemies was investigated in wheat fields. The spatial distribution of S. avenae was also analysed. Compared with monocultures, Beijing 837, the number of S. avenae apterae per 100 plants in intercropping patterns was significantly lower during the aphid peak period, and the cascade of population densities was: Beijing 837 monoculture (7422.0) > intercropped with KOK (5796.7) > intercropped with Hongmanghong (5406.7) > intercropped with Zhengzhou831 (5291.7) > intercropped with JP2 (4493.4) > intercropped with Zhongsiwumang (4155.0). The spatial distribution of S. avenae was changed from aggregated to uniform pattern. In the aphid parasitoid peak period, there were higher population densities of the aphid parasitoids in each intercropping field with a very significant level of P
  • Authors:
    • Al-Dalain, S.
  • Source: Agricultural Journal
  • Volume: 4
  • Issue: 3
  • Year: 2009
  • Summary: This research was carried out during two growing seasons of 2006/2007-2007/2008 in order to determine the effect of intercropping of zea maize ( Miert cultivar) with potato ( Marfona cultivar) on potato growth and on the productivity and Land Equivalent Ratio (LER) of potato and maize. The results of this research showed that intercropping of maize with potato in the case of equal plant densities (4.76 plant m -2) of both crops caused an increase in the mean length of potato stems, which reached 27.45 cm. Moreover, intercropping of maize of 2.38 plant m -2 led into the increase of the mean weight of potato shoots (fresh and dry) to 227 and 21.28 g plant -1 for fresh and dry weight, respectively, besides the increase of the mean weight of potato tubers, which reached 101 g tuber -1. Results also, showed that the number of potato stems and formed tubers were not affected by intercropping of maize with potato. As for productivity, results indicated that the total productivity of each unit area using intercropping system was higher than the productivity of the sole crop, with superiority of treatments with 2.38 plant m -2 of maize and 4.76 plant m -2 of potato where mean yield of 44 ton ha -1, while, the productivity in the other treatments were 36 and 37.8 ton ha -1. LER showed positive influence using the intercropping system compared to the sole cropping, as it shown in the LER values, which were higher (1.43-1.55) in intercropping compared to (1) in the sole cropping.
  • Authors:
    • Meera, P.
    • Pandey, A.
    • Amarnath, S.
  • Source: Environment and Ecology
  • Volume: 27
  • Issue: 3A
  • Year: 2009
  • Summary: A field experiment was conducted during three consecutive years of 2000-01 to 2002-03 to study the nutrient management on yield, quality and fertility status in tobacco based intercropping system in North Bihar. Results revealed that significantly highest cured and first grade leaf yield of tobacco was obtained in tobacco+garlic than other intercropping systems. Highest net and gross return and cost: benefit ratio were realized in tobacco+garlic followed by tobacco+rajmash and tobacco+potato intercropping systems. Application of 100% recommended dose of fertilizers (RDF) produced significantly highest cured and first grade leaf yield of tobacco as compared to rest of the fertility levels. Application of 100% RDF registered more gross and net returns and cost: benefit ratio. The physical parameters of maturity score was recorded more in tobacco+garlic intercropping and application of 100% RDF. Physical and chemical compositions of soil after harvest of tobacco was restored more in 100% RDF along with tobacco+garlic intercropping.
  • Authors:
    • Animesh, S.
  • Source: Journal of Bamboo and Rattan
  • Volume: 8
  • Issue: 1/2
  • Year: 2009
  • Summary: The feasibility of cultivation of winter vegetables under bamboo was assessed on the basis of their growth and yield. Recently Dendrocalamus asper, an edible and exotic bamboo species has been introduced in India. In the present study four-years-old plantation of D. asper raised through tissue culture was intercropped with potato ( Solanum tuberosum), tomato ( Lycopersicon esculentum) and pea ( Pisum sativum). Vegetable crops showed variable performance under bamboo as compared to control. Among three winter vegetable crops, pea was found most compatible with D. asper.
  • Authors:
    • Javanshir, A.
    • Moghaddam, M.
    • Salmasi, S.
    • Nassab, A.
    • Asl, A.
  • Source: Journal of Food Agriculture & Environment
  • Volume: 7
  • Issue: 2
  • Year: 2009
  • Summary: In order to evaluate different proportions of intercropping potato ( Solanum tuberosum L.) and pinto bean ( Phaseolus vulgaris L.) with their sole cropping, two experiments were carried out in Agricultural Research Station of University of Tabriz in 2005 and 2006, using randomized complete block design with three replications of eight treatments of replacement intercropping with proportions 2:1 and 3:1 of potato with pinto bean, (the densities of potato 4.7 and 5.3 plants per m 2 and those of pinto bean 45 and 55 plants per m 2) along with two sole cropping treatments of potato (4.7 and 5.3 plants per m 2) and two sole cropping treatments of pinto bean (with 45 and 55 plants per m 2). In all intercropping plots, tuber yield per m 2 and per plant, number of leaves and branches and size of tuber per plant increased significantly as compared with their sole croppings. For pinto bean also, grain yield per m 2 and per plant, number of pods per plant and number of leaves and branches per plant increased significantly as compared with their sole croppings. Highest amounts of LER in two years (1.25 and 1.27) were related to intercropping proportion of 2:1 (66% potato with density of 5.3 plants per m 2+34% pinto bean with the density of 55 plants per m 2). We can infer that these two crops have used more environmental resources in intercropping than sole croppings due to increase in Resources Use Efficiency (RUE).
  • Authors:
    • Suleau, M.
    • Heinesch, B.
    • Dufranne, D.
    • Bodson, B.
    • Moureaux, C.
    • Aubinet, M.
    • Vancutsem, F.
    • Vilret, A.
  • Source: Agricultural & Forest Meteorology
  • Volume: 149
  • Issue: 3/4
  • Year: 2009
  • Summary: A crop managed in a traditional way was monitored over a complete sugar beet/winter wheat/potato/winter wheat rotation cycle from 2004 to 2008. Eddy covariance, automatic and manual soil chamber, leaf diffusion and biomass measurements were performed continuously in order to obtain the daily and seasonal Net Ecosystem Exchange (NEE), Gross Primary Productivity (GPP), Total Ecosystem Respiration (TER), Net Primary Productivity (NPP), autotrophic respiration, heterotrophic respiration and Net Biome Production (NBP). The results showed that GPP and TER were subjected to important inter-annual variability due to differences between crops and to climate variability. A significant impact of intercrop assimilation and of some farmer interventions was also detected and quantified. Notably, the impact of ploughing was found to be limited in intensity (1-2 mol m -2 s -1) and duration (not more than 1 day). Seasonal budgets showed that, during cropping periods, the TER/GPP ratio varied between 40 and 60% and that TER was dominated mainly by the autotrophic component (65% of TER and more). Autotrophic respiration was closely related to GPP during the growth period. The whole cycle budget showed that NEE was negative and the rotation behaved as a sink of 1.59 kgC m -2 over the 4-year rotation. However, if exports are deducted from the budget, the crop became a small source of 0.22 (0.14) kgC m -2. The main causes of uncertainty with these results were due to biomass samplings and eddy covariance measurements (mainly, uncertainties about the u* threshold determination). The positive NBP also suggested that the crop soil carbon content decreased. This could be explained by the crop management, as neither farmyard manure nor slurry had been applied to the crop for more than 10 years and because cereal straw had been systematically exported for livestock. The results were also strongly influenced by the particular climatic conditions in 2007 (mild winter, and dry spring) that increased the fraction of biomass returned to the soil at the expense of harvested biomass, and therefore mitigated the source intensity. If 2007 had been a 'normal' year, this intensity would have been twice as great. This suggests that, in general, the rotation behaved as a small carbon source, which accords with similar studies based on multi-year eddy covariance measurements and export assessment and with modelling or inventory studies analysing the evolution of crop soil organic carbon (SOC) on a decennial scale.
  • Authors:
    • Cadet, P.
    • Spaull, V.
    • Dana, P.
    • Berry, S.
  • Source: Nematropica
  • Volume: 39
  • Issue: 1
  • Year: 2009
  • Summary: Two trials were planted on sandy soils on small-scale grower farms to study the effect of intercropping on the nematode fauna, soil and plant fertility and sugarcane yield. Peanut ( Arachis hypogaea) and sugar bean ( Phaseolus limensis) were intercropped between the sugarcane rows in the first trial; velvet bean ( Mucuna deeringiana) and sweet potato ( Ipomoea batatas) were intercropped in the second trial. These practices were compared to a standard aldicarb (nematicide) treatment and an untreated control. In the first trial (irrigated sugarcane), peanut grew well as an intercrop, however, 70% of the sugar bean died before producing seeds. Intercropping with sugar bean had no effect on initial sugarcane stalk number whereas peanut reduced initial sugarcane stalk number by 30%. In the second trial (non-irrigated sugarcane), both velvet bean and sweet potato grew well as intercrops. Intercropping resulted in initial reduction in sugarcane stalk number of 30% for sweet potato and 70% for velvet bean. However, for both trials, and for all intercrops (except peanut), the sugarcane stalk number at harvest was the same as that of the control. Intercropping with velvet bean, peanut and sweet potato increased Meloidogyne javanica and Pratylenchus zeae infestation of the sugarcane sett roots; conversely, intercropping with sugar bean reduced nematode infestation. Intercropping with velvet bean, sugar bean and sweet potato had no effect on sugarcane yield, whereas intercropping with peanut reduced sugarcane yield by 22% and sucrose yield by 29%. Intercropping with velvet bean increased levels of some nutrients in the soil and leaves of sugarcane. These results show that intercropping can be used by small-scale growers to: manage nematodes (sugar bean), provide nutrients to the sugarcane crop (velvet bean), provide alternative food source and/or income (sweet potatoes) and to improve the overall productivity of the land without being detrimental to sugarcane cultivation.
  • Authors:
    • Ramakrishna, A.
    • Bourke, R.
  • Source: ACIAR Technical Reports Series
  • Issue: 71
  • Year: 2009
  • Summary: Sweetpotato was introduced into Papua New Guinea (PNG) from eastern Indonesia about 300 years ago and now dominates agricultural production in the PNG highlands. The environments in which it is grown in the highlands are briefly reviewed. The main components of the agricultural systems in which it is grown are noted, including type of fallow vegetation cleared for cultivation, fallow period, cropping period before fallow, intercropping, seasonality, soil fertility maintenance techniques, mounding and drainage. The importance of the crop in highlanders' diets and agricultural systems is briefly reviewed, as is the crop's role as pig fodder and the quantity sold in fresh food markets. Some possible future trends for sweetpotato in the highlands conclude the paper.
  • Authors:
    • Govindakrishnan, P.
    • Lal, S.
    • Dua, V.
  • Source: Indian Journal of Agricultural Sciences
  • Volume: 79
  • Issue: 5
  • Year: 2009
  • Summary: A field experiment was conducted at Shimla, Himachal Pradesh, India, during 2003-06, to determine the nutrient requirement of French bean ( Phaseolus vulgaris) when intercropped with potato ( Solanum tuberosum) under 2:2 row ratio in which 2 rows of French bean (paired at 30 cm) were planted at 2 population densities (88 888 plants/ha with 15 cm plant spacing and 133 333 plants/ha with 10 cm plant spacing) after every 2 rows of potato planted at 50 cm. Potato tuber yield was not affected since it was supplied with a uniform recommended dose of NPK and farmyard manure in all the treatments. Results revealed that in the potato+French bean (2:2) intercropping, French bean required only 2/3 of the recommended NPK and farmyard manure, applied on the basis of their sole crop density in intercropping, irrespective of its planting spacing. The increase in pod yield of French bean under this treatment over control was 1.62 tonnes/ha (38.7%) and 1.78 tonnes/ha (37.0%) at population densities of 88 888 and 133 333 plants/ha, respectively. At this level of fertility, French bean with 133 333 plants/ha gave 13.4% more pods (0.78 tonnes/ha) than with 88 888 plants/ha. The nutrient balance was also positive as the removal of N, P and K was 40.6, 31.2 and 44.1%, respectively, with 88 888 plants/ha of French bean and 39.3, 27.1 and 42.7%, respectively, with 133 333 plants/ha of Frenchbean grown with 2/3 of recommended NPK+farmyard manure. The economics was also favourable for these treatments.