• Authors:
    • Pompa, M.
    • Giuzio, L.
    • Ficco, D. B. M.
    • Borrelli, G. M.
    • Cattivelli, L.
    • Flagella, Z.
  • Source: Cereal Research Communications
  • Volume: 39
  • Issue: 4
  • Year: 2011
  • Summary: Durum wheat (Triticum turgidum L. Desf.) is a species well adapted to the Mediterranean environments where salt stress due to seawater intrusion is an increasing problem. The purpose of this study was to deep insight into the relationships among physiological, productive and qualitative aspects under salinity, being these aspects still poorly investigated in durum wheat. In 2004-2005 crop season 10 durum wheat genotypes of different origin and breeding time were grown in a naturally-lit polycarbonate greenhouse under three irrigation water salinity levels (0.9, 6.0 and 12.0 dS m -1). A complete randomized block design with three replications was adopted. The osmotic damage was evaluated by estimating relative water content (RWC), leaf water potential (Phi w) and osmotic potential at full turgor (Phi pi100). The toxic damage to the plants was evaluated by measuring Na + accumulation and Na +/K + ratio in the leaves. Differences in yield performance were evaluated by assessing the main yield components and some qualitative traits, carotenoid pigment and protein content and Sedimentation test in sodium dodecyl sulphate. A significant effect of genotype, salt stress and of their interaction on all the characters was observed. Durum wheat genotypes generally showed a moderate tolerance to salt stress. The genotype performance was dependent on stress level and RWC maintenance. Osmotic adjustment and low sodium accumulation were found to play a key role in salt tolerance. An improvement in the grain quality characters on increasing salinity level, consistently with a yield decrease, was observed.
  • Authors:
    • Pecchioni, N.
    • Perata, P.
    • Milc, J.
    • Meriggi, P.
    • Arru, L.
    • Caffagni, A.
  • Source: Communications in Soil Science and Plant Analysis
  • Volume: 42
  • Issue: 6
  • Year: 2011
  • Summary: Iodine is an essential microelement for human health, and the recommended daily allowance (RDA) of such element should range from 40 to 200 g day -1. Because of the low iodine contents in vegetables, cereals, and many other foods, iodine deficiency disorder (IDD) is one of the most widespread nutrient-deficiency diseases in the world. Therefore, investigations of I uptake in plants with the aim of fortifying them can help reach the important health and social objective of IDD elimination. This study was conducted to determine the effects of the absorption of iodine from two different chemical forms - potassium iodide (I -) and potassium iodate (IO -3) - in a wide range of wild and cultivated plant species. Pot plants were irrigated with different concentrations of I - or IO -3, namely 0.05% and 0.1% (w/v) I - and 0.05%, 0.1%, 0.2%, and 0.5% (w/v) IO -3. Inhibiting effects on plant growth were observed after adding these amounts of iodine to the irrigation water. Plants were able to tolerate high levels of iodine as IO -3 better than I - in the root environment. Among cultivated species, barley ( Hordeum vulgare L.) showed the lowest biomass reductions due to iodine toxicity and maize ( Zea mays L.) together with tobacco ( Nicotiana tabacum L.) showed the greatest. After the screening, cultivated tomato and potato were shown to be good targets for a fortification-rate study among the species screened. When fed with 0.05% iodine salts, potato ( Solanum tuberosum L.) tubers and tomato ( Solanum lycopersicum L.) fruits absorbed iodine up to 272 and 527 g/100 g fresh weight (FW) from IO -3 and 1,875 and 3,900 g/100 g FW from I -. These uptake levels were well more than the RDA of 150 g day -1 for adults. Moreover, the agronomic efficiency of iodine accumulation of potato tubers and tomato fruits was calculated. Both plant organs showed greater accumulation efficiency for given units of iodine from iodide than from iodate. This accumulation efficiency decreased in both potato tubers and tomato fruits at iodine concentrations greater than 0.05% for iodide and at respectively 0.2% and 0.1% for iodate. On the basis of the uptake curve, it was finally possible to calculate the doses of supply in the irrigation water of iodine as iodate (0.028% for potato and 0.014% for tomato) as well as of iodide (0.004% for potato and 0.002% for tomato) to reach the 150 g day -1 RDA for adults in 100 g of such vegetables, to efficiently control IDD, although these results still need to be validated.
  • Authors:
    • Tello-Marquina, J. C.
    • Gómez-Vázquez, J.
    • Santos-Hernández, M.
    • Pérez-Vargas, M.
    • Palmero, D.
    • de Cara, M.
  • Source: Acta Horticulturae
  • Issue: 914
  • Year: 2011
  • Summary: Cherry tomato crops were introduced in the late 1990s in the continental areas of southeast Spain. These fields had been previously cultivated with dry land crops as grapevine, olive, and cereal. After two years of cultivation, different soil-borne diseases widely appeared. The main disease observed was the root rot caused by Phytophthora parasitica, killing the plants during harvest period, concurring with the maximum demand of water from plants. The importance of the mycosis in the area together with the lack of control were the aim to first search for the inoculum sources, and then study the preservation of this oomycete in the infested soils for a long period time. Regarding the inoculum sources, no Phytophthora was found in seeds or seedlings from commercial nurseries sampled from the studied area, but the pathogen was isolated from the irrigation pools. Phytophthora parasitica was also isolated from the soils of the home gardens within the surrounded area, and even from the wheels of the tractors used in these fields. About the preservation study, a total of 92 samples from 42 different fields naturally infested with P. parasitica were analysed. All samples have been kept under laboratory conditions in sealed plastic bags. Only 20.58% of all samples preserved the oomycete for 4 years (48 months), and 18.18% for 5 years (57 months). These results can explain the rapid dissemination of the disease and its difficult control in the area.
  • Authors:
    • Aibar, J.
    • Cirujeda, A.
    • Zaragoza, C.
  • Source: Agronomy for Sustainable Development
  • Volume: 31
  • Issue: 4
  • Year: 2011
  • Summary: Management practices, geographical gradients and climatic factors are factors explaining weed species composition and richness in cereal fields from Northern and Central Europe. In the Mediterranean area, the precise factors responsible for weed distribution are less known due to the lack of data and surveys. The existence of weed survey data of year 1976 in the Zaragoza province of the Aragon region, Spain, offered us the opportunity to compare present weed species with weed species growing 30 years ago. No detailed comparison of changes in weed species composition in cereal fields in that period of time has been conducted in the Mediterranean area. Here a survey was conducted in the Aragon region from 2005 to 2007. Weeds were surveyed in 138 winter cereal fields in ten survey areas where winter cereals are the main crops, using the same methodology applied 30 years ago. In the Zaragoza province, 36 fields were chosen in the same municipalities than in the previous survey. Several management, geographic and climatic variables of each field were recorded and related to weed species with multivariate analysis. Diversity index were calculated and related to survey area and altitude. Our results show that out of the 175 species only 26 species were found in more than 10% of the surveyed fields. The main species were Papaver rhoeas, Lolium rigidum, Avena sterilis and Convolvulus arvensis found in more than half of the surveyed fields. L. rigidum was related to dryland, while the other species were found overall. Furthermore, we found that management, geographical and climatic factors were significantly related to weed species distribution. In particular altitude, survey areas, irrigation and herbicide use in post-emergence were the most driving factors explaining weed species distribution. Species richness was higher in survey areas with extensive management practices and increased with altitude excepting a very productive area with intensive management practices at high altitude where richness was as low as in the irrigated lowlands. The main differences found between the 1976 and the 2005-2007 surveys were (1) the striking increase of grass weeds, (2) the high decrease of mean weed species number found in each field declining from 9 to 3 and (3) the frequency decrease of many weed species probably caused by agriculture intensification in that period of time. The growing importance of other weed species is probably related to their adaptation to minimum tillage, which is a widespread technique nowadays.
  • Authors:
    • Mohd, S.
    • Sulaiman, J.
    • Ahmed, E.
  • Source: American Journal of Agricultural and Biological Sciences
  • Volume: 6
  • Issue: 3
  • Year: 2011
  • Summary: Problem statement: Field crops are considered as essential cash and food crops produced in River Nile State (RNS) of North Sudan include cereal, food-legumes, vegetables and fodders beside the perennial crops. They are the main source of household income and regarded as a major part of the daily diet for the Sudanese. In other words they play an important role in household food security and poverty alleviation. However, resources use efficiency for producing these crops is became critical due to high competition from high population pressure and chronic low and instable crop yields emanating from environmental stresses and poor use of improved technology pose challenges for resource management. Since resources are most essential economical inputs, the target should be when optimizing resources use to obtain maximum productivity per unit. The RNS is considered as one of the main supplier of these cereal and foodlegume crops to the country. The crops are commonly produced under pump irrigation from the River Nile. The production of field crops in the State are faced by numerous constraints namely inefficiency of resources use, low level of productivity and high cost of production. The study aims to assess the allocation of the available resources use over the competitive field crops of the dominant crop combination. Approach: It was on this basis that a study was prepared out in RNS to establish resource combination levels that maximize gross margins from food and cash crops that commonly grown within the combination. Primary data was collected by using structured questionnaires for (70) randomly selected respondents from Elzeidab scheme public irrigated scheme of RNS as a case study. A linear programming technique through the General Algebraic Modeling System (GAMS) program was used to assess the optimally combining resources in the prevalent field crops. Results: The model results revealed that tenants would get higher returns by allocating more resources namely land, water, labor and capital to the food legume crops production. Higher net benefits would be from food legume crops production and least from exclusion them. Conclusion: The RNS tenants should therefore, be guided on how to optimally and efficiently utilize their resources and be encouraged to grow food legume crops that give production and yield advantages, earn high returns and contributed significantly to farm sustainability and alleviates malnutrition in RNS.
  • Authors:
    • Lawn, R. J.
    • Gaynor, L. G.
    • James, A. T.
  • Source: Crop & Pasture Science
  • Volume: 62
  • Issue: 12
  • Year: 2011
  • Summary: The response of irrigated soybean to sowing date and to plant population was evaluated in field experiments over three years at Leeton, in the Murrumbidgee Irrigation Area (MIA) in southern New South Wales. The aim was to explore the options for later sowings to improve the flexibility for growing soybean in double-cropping rotations with a winter cereal. The experiments were grown on 1.83-m-wide raised soil beds, with 2, 4, or 6 rows per bed (years 1 and 2) or 2 rows per bed only (year 3). Plant population, which was manipulated by changing either the number of rows per bed (years 1 and 2) or the within-row plant spacing (year 3), ranged from 15 to 60 plants/m 2 depending on the experiment. Two sowings dates, late November and late December, were compared in years 1 and 3, while in year 2, sowings in early and late January were also included. Three genotypes (early, medium, and late maturity) were grown in years 1 and 2, and four medium-maturing genotypes were grown in year 3. In general, machine-harvested seed yields were highest in the November sowings, and declined as sowing was delayed. Physiological analyses suggested two underlying causes for the yield decline as sowing date was delayed. First and most importantly, the later sown crops flowered sooner after sowing, shortening crop duration and reducing total dry matter (TDM) production. Second, in the late January sowings of the medium- and late-maturing genotypes, harvest index (HI) declined as maturity was pushed later into autumn, exposing the crops to cooler temperatures during pod filling. Attempts to offset the decline in TDM production as sowing was delayed by using higher plant populations were unsuccessful, in part because HI decreased, apparently due to greater severity of lodging. The studies indicated that, in the near term, the yield potential of current indeterminate cultivars at the late December sowing date is adequate, given appropriate management, for commercially viable double-cropping of soybean in the MIA. In the longer term, it is suggested that development of earlier maturing, lodging-resistant genotypes that retain high HI at high sowing density may allow sowing to be delayed to early January.
  • Authors:
    • Tabatabaei, B. E. S.
    • Maibody, S. A. M. M.
    • Arzani, A.
    • Golabadi, M.
    • Mohammadi, S. A.
  • Source: Euphytica
  • Volume: 177
  • Issue: 2
  • Year: 2011
  • Summary: Grain yield and yield components are the main important traits involved in durum wheat ( Triticum turgidum L.) improvement programs. The purpose of this research was to identify quantitative trait loci (QTL) associated with yield components such as 1000 grain weight (TGW), grain weight per spike (GWS), number of grains per spike (GNS), spike number per m 2 (SN), spike weight (SW), spike harvest index (SHI) and harvest index (HI) using microsatellite markers. Populations of F 3 and F 4 lines derived from 151 F 2 individuals developed from a cross between Oste-Gata, a drought tolerant, and Massara-1, a drought susceptible durum wheat genotypes, were used. The populations were evaluated under four environmental conditions including two irrigation regimes of drought stress at terminal growth stages and normal field conditions in two growing seasons. Two hundred microsatellite markers reported for A and B genomes of bread wheat were used for parental polymorphism analysis and 30 polymorphic markers were applied to genotype 151 F 2:3 families. QTL analysis was performed using genome-wide single marker regression analysis (SMA) and composite interval mapping (CIM). The results of SMA revealed that about 20% of the phenotypic variation of harvest index and TGW could be explained by Xcfd22-7B and Xcfa2114-6A markers in different environmental conditions. Similarly, Xgwm181-3B, Xwmc405-7B and Xgwm148-3B and marker Xwmc166-7B were found to be associated with SHI and GWS, respectively. A total of 20 minor and major QTL were detected; five for TGW, two for GWS, two for GNS, three for SN, five for HI, two for SHI and one for SW. The mapped QTL associated with ten markers. Moreover, some of these QTL were prominent and stable under drought stress and non drought stress environments and explained up to 49.5% of the phenotypic variation.
  • Authors:
    • Galusha, T. D.
    • Jackson, D. S.
    • Mason, S. C.
    • Griess, J. K.
    • Pedersen, J. F.
    • Yaseen, M.
  • Source: Crop Science
  • Volume: 51
  • Issue: 4
  • Year: 2011
  • Summary: Grain processors would benefit from information about the production environment and the influences of the sorghum [ Sorghum bicolor (L.) Moench] hybrid on food-grade flour properties. The objective of this study was to determine the effects of environment and hybrid on rapid-visco-analysis (RVA) flour properties of commercially available food-grade sorghum. A randomized complete block experiment was planted in 12 environments, which included the 2004 and 2005 growing seasons and irrigated and dryland water regimes in eastern, central, and west central Nebraska, and a dryland, low-N environment in eastern Nebraska. The environment accounted for 71-85% of the total variation in RVA parameters, while the hybrid accounted for 11-23% and the environment-by-hybrid interaction, 1-3%. Unfortunately, the results of this experiment suggest that it is difficult to predict the effect that environment will have on resulting sorghum-flour parameters. Although of secondary importance in terms of total variation in sorghum-flour RVA properties, the choice of hybrid predictably and significantly contributes to sorghum-starch viscosity properties. Food-grade hybrids were grouped based on viscosity properties into those best suited for dry-mill and alkaline-cooked products (Asgrow Orbit; Sorghum Partners NK1486) and those best suited for porridge, consumable alcohol, and ethanol production (Kelly Green Seeds KG6902; NC+ Hybrids 7W92; Asgrow Eclipse; and Fontanelle W-1000). These results were consistent with those previously reported for grain density.
  • Authors:
    • Ganji, A.
    • Mousavi, S. F.
    • Lee, T. S.
    • Soom, M. A. M.
    • Salemi, H.
    • KamilYusoff, M.
  • Source: African Journal of Agricultural Research
  • Volume: 6
  • Issue: 10
  • Year: 2011
  • Summary: Simulation models that clarify the effects of water on crop yield, are useful tools for improving farm-level water management and optimizing water use efficiency. The main purpose of deficit irrigation is high water productivity with less water supply to plants. In this research, the potential of AquaCrop model in deficit irrigation practice for winter wheat, the main agronomic crop in Gavkhuni river basin, Isfahan province, Iran, was studied. The results of reliability indices such as RMSE, d, E, CRM and deviation percent were 2.31 to 5.63, 0.97 to 1.00, 93 to 99, -0.15 to 0.016 and -0.70 to 12.00% respectively, and showed that, the model overestimated the simulated parameters compared with field data. This difference was more obvious in deficit irrigation treatments. The model provided excellent simulations of canopy cover, grain yield and water productivity. Considering only drought stress and neglecting other stresses such as salinity is the most important limitation of AquaCrop model. In this study, water productivity for the studied crop was in the range of 0.91 to 1.49 kg m -3 and its maximum value was in 40% deficit irrigation treatment. A second-order, yield-water function, obtained in this study is recommended for winter wheat crop. Also, the sensitivity analysis of AquaCrop model was carried out for winter wheat in this arid area in central Iran.
  • Authors:
    • Kalamkar, S. S.
  • Source: Agricultural Economics Research Review
  • Year: 2011
  • Summary: District-wise growth and the reasons behind stagnation in the productivity of important agricultural crops in Maharashtra are considered. Secondary data for the period 1960/61 - 2004/05 is used to analyse the growth pattern of production and productivity, and the regional variations of stagnation for cereals, pulses, oilseeds, cotton and sugarcane. Agricultural growth constraints are identified and district-level interventions to overcome the problems of stagnation are suggested. Measures for growth in TFP are recommended that include watershed development and rainwater harvesting, the supply of good quality inputs, greater research into increasing crop yields, and flexible credit facilities. Greater horticultural production and irrigation, and the development of drought-resistant, high yielding variables more suited to the agro-climate of the State are also suggested.