• Authors:
    • Li, S.
    • Zheng, Y.
    • Tang, L.
    • Qiao, P.
  • Source: Plant Nutrition and Fertilizer Science
  • Volume: 16
  • Issue: 5
  • Year: 2010
  • Summary: Crop varieties are different in nutrient uptake, and intercropping may influence nutrient uptake and disease incidence of the crops. Pot experiments were carried out to investigate the characteristics of N, P and K uptake and powdery mildew incidence of 6 wheat cultivars, which differed in powdery mildew resistance and were intercropped with faba bean: 2 highly resistant cultivars YM47 and YM53, 2 medium resistant cultivars YM42 and YM51 and 2 sensitive cultivars YX11-12 and YX93-124. The biomass of YM47 and YM53 increased by 11.9% and 6.6% in intercropping, compared with that in mono-cropping. Nitrogen contents of the leaves of intercropped wheat cultivars YM47 and YM53 and YX11-12 significantly increased, by 1.20-1.25 times in comparison with those of mono-cropping. The phosphorus contents of wheat leaves increased at the milky and ripening stages, and potassium content of wheat leaves significantly increased by 9.1-22.3% at the jointing stage under the intercropping. The incidence of wheat powdery mildew of all wheat cultivars significantly decreased under the intercropping system, the relative disease controlling effects being 0.76-81.49%. The most desirable disease-controlling effects under the intercropping were observed in YM42, YM53 and YM93-142 at the milky stage.
  • Authors:
    • Dhyani, S. K.
    • Dar, S. A.
    • Ram, N.
  • Source: Indian Journal of Agricultural Sciences
  • Volume: 80
  • Issue: 5
  • Year: 2010
  • Summary: A field experiment was conducted during 2005-07 at Jhansi to elucidate the influence of shoot pruning on growth of [ Albizia procera (Roxb.) Benth] and grain yield of intercrop. The experiment was conducted in split plot design with 2 crop sequences, namely blackgram ( Vigna mungo (L.) Hepper) - mustard ( Brassica juncia L. Czern. & Coss.) and greengram ( Vigna radiata Roxb.) - wheat ( Triticum aestivum L. emend. Friori & Paol.) with 3 pruning regimes (70% canopy pruning, 50% canopy pruning and control unpruned). The results reveal that the growth of A. procera (dbh, height and canopy diameter) was significantly ( P <br/> 0.05) higher in control (unpruned trees) compared with the 50% canopy pruning and 70% canopy pruning. Grain yield of greengram-wheat crop sequence was 41.21 and 83.45% higher than the blackgram-mustard crop sequence. Among the pruning regimes, 70% canopy pruning gave 129.94% higher grain yield than the control (unpruned trees).
  • Authors:
    • Garcia, R.
    • Werle, R.
    • Rosolem, C.
  • Source: REVISTA BRASILEIRA DE CIENCIA DO SOLO
  • Volume: 34
  • Issue: 6
  • Year: 2010
  • Summary: Crop species with the C 4 photosynthetic pathway are more efficient in assimilating N than C 3 plants, which results in different N amounts prone to be washed from its straw by rain water. Such differences may affect N recycling in agricultural systems where these species are grown as cover crops. In this experiment, phytomass production and N leaching from the straw of grasses with different photosynthetic pathways were studied in response to N application. Pearl millet ( Pennisetum glaucum) and congo grass ( Brachiaria ruziziensis) with the C 4 photosynthetic pathway, and black oat ( Avena Strigosa) and triticale (* Triticosecale), with the C 3 photosynthetic pathway, were grown for 47 days. After determining dry matter yields and N and C contents, a 30 mm rainfall was simulated over 8 t ha -1 of dry matter of each plant residue and the leached amounts of ammonium and nitrate were determined. C 4 grasses responded to higher fertilizer rates, whereas N contents in plant tissue were lower. The amount of N leached from C 4 grass residues was lower, probably because the C/N ratio is higher and N is more tightly bound to organic compounds. When planning a crop rotation system it is important to take into account the difference in N release of different plant residues which may affect N nutrition of the subsequent crop.
  • Authors:
    • Kripa, S.
    • Singh, R.
  • Source: Annals of Plant Protection Sciences
  • Volume: 18
  • Issue: 2
  • Year: 2010
  • Summary: Field studies were conducted in Uttar Pradesh, India, during the 2007/08 and 2008/09 rabi seasons, to determine the effect of intercropping on the mustard aphid ( Lipaphis erysimi) incidence. Indian mustard was intercropped with wheat, barley, pea, chickpea, lentil, linseed and radish, with a sole crop of Indian mustard as the control. The aphid population was determined and yield was recorded at harvest. Results showed that mustard intercropped with barley registered minimum mean aphid population index (2.35) and maximum mean yield of mustard (2.67 q/ha), followed by mustard + wheat, having mean aphid index of 2.53 q/ha and 2.67 q/ha, respectively. Mustard intercropped with linseed and chickpea were also better than the control in checking the incidence of mustard aphid, having 2.88 and 3.09 mean aphid indexes, respectively. However, the mustard intercropped with pea, lentil and radish were at par with the control.
  • Authors:
    • Brenneman, T.
    • Sorensen, R.
    • Lamb, M.
  • Source: Peanut Science
  • Volume: 37
  • Issue: 1
  • Year: 2010
  • Summary: Strip tillage with various crop covers in peanut ( Arachis hypogaea, L.) production has not shown a clear yield advantage over conventional tillage, but has been found to reduce yield losses from some diseases. This study was conducted to determine pod yield and disease incidence between two tillage practices, five winter cover crops, three peanut cultivars, and three fungicide programs. Conventional and strip tillage treatments were implemented on a Greenville sandy loam (fine, kaolinitic, thermic Rhodic Kandiudults) near Shellman, GA. Five winter cereal grain cover crops (strip tillage) and a no-cover crop treatment were sprayed at recommended (1R), half recommended (0.5R) or untreated (0R) fungicide programs. Within peanut cultivars, leaf spot ( Cercospora arachidicola Hori) intensity decreased as the number of fungicide applications increased; however, stem rot ( Sclerotium rolfsii) incidence was the same for the 1R and 0.5R fungicide programs but increased 0R program. Conventional tilled peanuts developed more leaf spot compared with strip tillage. There was no difference in leaf spot ratings among winter crop covers. There was no difference in stem rot incidence with tillage or winter cover crop. There was no yield difference with peanut cultivar. Pod yield was the same for the 1R and 0.5R fungicide program (3867 kg/ha) but decreased at the 0R fungicide program (2740 kg/ha). Pod yield was greater with conventional tillage and strip tillage with black oats ( Avena sativa L.) (3706 kg/ha) compared with strip tillage of other winter crop cover treatments (3358 kg/ha). Conventional tillage had more leaf spot, equal incidence of stem rot, and higher yield compared with strip tillage. The 0.5R fungicide program had the same yield compared with the 1R fungicide program implying a possible 50% savings on fungicide applications on well rotated fields with lower disease risk.
  • Authors:
    • Galizio, R.
    • Moreno, M. V.
    • Dinolfo, M. I.
    • Stenglein, S. A.
    • Salerno, G.
  • Source: PLANT DISEASE
  • Volume: 94
  • Issue: 6
  • Year: 2010
  • Summary: In December 2008, a study of oat (cv. Graciela INTA) seeds from Trenque Lauquen, Buenos Aires, Argentina, was conducted. Seeds were surface sterilized by dipping successively into 70% ethanol for 2 minutes, 5% sodium hypochlorite for 2 minutes, rinsed twice in fresh sterilized distilled water, plated on 2% potato dextrose agar (PDA; pH 6) and incubated at 242°C with 12 h photoperiods. Six isolates morphologically similar to Fusarium spp. were observed after 6 days of incubation. For identification, monosporic isolates were transferred onto 2% PDA and carnation leaf agar (CLA) to grow with the conditions described above. Two isolates produced abundant, white, aerial mycelium and violet-to-dark (with age) pigments in the PDA. On CLA, macroconidia were abundant, slender, almost straight, thin walled and usually 3-5 septate. Microconidia were abundant, usually single celled, oval or club-shaped in chains (less commonly in false heads) on monophialides and polyphialides. Chlamydospores were absent. The fungus was identified as F. proliferatum based on fungal morphology. The pathogenicity of the fungus was tested by spraying 5 healthy inflorescences of oat with a 5 ml suspension (2 * 10 5 conidia/ml). Another 2 healthy inflorescences were sprayed with sterile distilled water. Plants were placed in a growth chamber with a 12 h photoperiod at 222°C and covered with polyethylene bags that were removed after 3 days and plants were moved to a glasshouse. Inoculated inflorescences showed bleaching glumes that sometimes became necrotic with some grains that presented pale brown discoloration and necrotic areas. The fungus was reisolated from glumes and grains of inoculated plants and not from controls. To confirm the morphological diagnosis, the genomic DNA of the isolates was extracted and a PCR reaction with specific primers was chosen. Successful amplifications were confirmed by gel electrophoresis. The size of the DNA fragment was estimated using a 100 bp DNA ladder. The expected size product (585 bp) was obtained, confirming the identification. This is thought to be the first report of F. proliferatum on oat in Argentina.
  • Authors:
    • Somendra, N.
    • Anand, K.
    • Tripathi, A.
  • Source: Indian Journal of Agricultural Sciences
  • Volume: 80
  • Issue: 2
  • Year: 2010
  • Summary: A field experiment was carried out during winter ( rabi) seasons of 2003-04 and 2004-05 at Kanpur to find out the production potential and economic viability of winter maize ( Zea mays L.) intercropped with potato ( Solanum tuberosum L.), Indian mustard [ Brassica juncea (L.) Czernj. & Cosson], toria ( Brassica campestris var. toria), pea ( Pisum sativum L. sensulato), linseed ( Linum usitatissimum L.) and wheat ( Triticum aestivum L. emend. Fiori & Paol.) for central plain zone of Uttar Pradesh. Values of land equivalent ratio (LER) and area-time equivalent ratio (ATER) with all the intercropping systems were greater indicating advantage in yield, land-use efficiency and monetary return/unit time and space over the respective monocultures. All the intercrops with maize recorded significantly higher maize-equivalent yield than the sole crop. Intercropping of maize with potato was more advantageous than the other intercrops. Maize+potato appeared to be biologically the most efficient and economically viable system giving the highest maize grain yield (6 091 kg/ha), maize-equivalent yield (13 792 kg/ha), production efficiency (276.1%), land equivalent ratio (2.14), area-time equivalent ratio (1.91), monetary advantage (Rs 39 017) and net realization (Rs 32 369/ha), followed by maize+pea. Indian mustard, toria and wheat were found non-compatible with winter maize.
  • Authors:
    • Shrikant, C.
    • Urkurkar, J.
    • Alok, T.
  • Source: Indian Journal of Agronomy
  • Volume: 55
  • Issue: 1
  • Year: 2010
  • Summary: Field experiments were conducted at Raipur in Inceptisols between 2003-04 and 2007-08 to compare organic, integrated and chemical fertilizer nutrient inputs pakages in scented rice ( Oryza sativa L.) - potato ( Solanum tuberosum L.) a high value cropping system. Seven different nutrient treatments, 5 of them having use of organic inputs and 1 each having integrated (50% through fertilizers and 50% through organic nutrients) and 100% through fertilizers were studied in RBD with 3 replications. Organic transition effect in which decline in yield from 1 to 3 years and again increase in yield was noticeable in rice under organic nutrient inputs packages. These treatments followed a steady increase and registered 20 to 50% more yield at the end of study compared to first year yield i.e. 2003-04. However, effect of different organic inputs packages on potato tuber yield was not stable over the years. Total productivity in terms of rice equivalent yield of the system (13.36 tonne/ha) and total net return (Rs 92,634/kg) was highest with chemical fertilizer treatment closely followed by integrated inputs use. 100% N (1/3 each from cowdung manure, neem cake and composed crop residue) appreciably increased the organic carbon (6.3 g/kg) over initial value (5.8 g/kg). However, availability of P and K did not show any perceptible change after completion of five cropping cycles under organic as well as integrated nutrient approaches.
  • Authors:
    • Kumar, S. N.
    • Byjesh, K.
    • Aggarwal, P. K.
  • Source: Mitigation and Adaptation Strategies for Global Change
  • Volume: 15
  • Issue: 5
  • Year: 2010
  • Summary: Climate change associated global warming, rise in carbon dioxide concentration and uncertainties in precipitation has profound implications on Indian agriculture. Maize ( Zea mays L.), the third most important cereal crop in India, has a major role to play in country's food security. Thus, it is important to analyze the consequence of climate change on maize productivity in major maize producing regions in India and elucidate potential adaptive strategy to minimize the adverse effects. Calibrated and validated InfoCrop-MAIZE model was used for analyzing the impacts of increase in temperature, carbon dioxide (CO 2) and change in rainfall apart from HadCM3 A2a scenario for 2020, 2050 and 2080. The main insights from the analysis are threefold. First, maize yields in monsoon are projected to be adversely affected due to rise in atmospheric temperature; but increased rainfall can partly offset those loses. During winter, maize grain yield is projected to reduced with increase in temperature in two of the regions (Mid Indo-Gangetic Plains or MIGP, and Southern Plateau or SP), but in the Upper Indo-Gangetic Plain (UIGP), where relatively low temperatures prevail during winter, yield increased up to a 2.7°C rise in temperature. Variation in rainfall may not have a major impact on winter yields, as the crop is already well irrigated. Secondly, the spatio-temporal variations in projected changes in temperature and rainfall are likely to lead to differential impacts in the different regions. In particular, monsoon yield is reduced most in SP (up to 35%), winter yield is reduced most in MIGP (up to 55%), while UIGP yields are relatively unaffected. Third, developing new cultivars with growth pattern in changed climate scenarios similar to that of current varieties in present conditions could be an advantageous adaptation strategy for minimizing the vulnerability of maize production in India.
  • Authors:
    • Kalungu, J. W.
    • Monteiro, R. O. C.
    • Coelho, R. D.
  • Source: Ciência Rural
  • Volume: 40
  • Issue: 10
  • Year: 2010
  • Summary: This paper reviews various irrigation technologies in both South Africa and Kenya that enable improvements in their socio-economic conditions. The two countries are located in semi-arid areas that experience extreme fluctuations in the availability of rain water for plant growth. Population growth exceeds the ability to produce food in numerous countries around the world and the two countries are not an exception. This experiment examined the constraints that farmers face and the role of government and nongovernmental organization in the uptake of modern technologies for irrigation. Detailed mechanisms and options to secure sustainable irrigation which are economically viable are considered. Despite the higher production of cereals and grains, fruits, and flowers also thrive in the two countries. Total irrigated area, crops grown and irrigation systems used in the two countries are discussed.