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A software model has been developed to estimate greenhouse gas emissions of pasture-fed ruminant farming systems. The model estimates on-farm emissions associated with livestock (sheep and beef), fertiliser, petrol, diesel and electricity. Carbon sequestration from native and exotic forestry is then included to produce an on-farm carbon footprint, in the form of carbon dioxide equivalents. This paper describes the livestock model, which has been designed to record the movement of animals within individual farm units according to defined livestock classes. Allowances are made for unrecorded deaths, by estimating the number of animals missing within a defined time period and spreading the deaths according to expected seasonal variation in mortality. The enteric methane and nitrous oxide emissions are predicted using a combination of customised growth and lactation curves, and internationally recognised formulae to predict nutrient energy requirements. Customised growth and lactation curves allow estimation of liveweights and energy requirements associated with maintenance, growth, pregnancy and lactation on a daily basis. Daily estimation of emissions reduces errors introduced by monthly or seasonal averaging of livestock numbers and liveweights. The model has been developed into a commercial application (Alliance Group hoofprint) for use by New Zealand sheep and beef farmers, and could be adapted for other international livestock farming operations. [ABSTRACT FROM AUTHOR]

Potassium (K) plays an important role in many physiological and biochemical processes in plants and its adequate use is an important issue for sustainable economic crop production. Soil test-based K fertilizer recommendations are very limited for lowland rice (Oryza sativa L.) grown on Inceptisols. The objective of this study was to calibrate K soil testing for the response of lowland rice (cv. Ipagri 109) to added K. A field experiment was conducted in the farmers' field in the municipality of Lagoa da Confusao, State of Tocantins, central Brazil. The K rates used were 0, 125, 250, 375, 500, and 625 kg K ha-1 applied as broadcast and incorporated during sowing of the first rice crop. Rice responded significantly to K fertilization during 2 years of experimentation. Maximum grain yield of about 6,000 kg ha-1 was obtained with 57 mg K kg-1 soil in the first year and with 30 mg K kg-1 in the second year. This indicated that at low levels of K in the soil, nonexchangeable K was available for plant growth. Potassium use efficiency designated as agronomic efficiency (kg grain produced/kg K applied) decreased significantly in a quadratic fashion with increasing K level in the soil. Agronomic efficiency had a significantly linear association with grain yield. Hence, improving agronomic efficiency with management practices can improve rice yield. [ABSTRACT FROM AUTHOR]

Abstract: A field experiment was conducted to investigate the impact of simulated rat damage on grain yield in irrigated lowland rice in An Giang province, in the Mekong Delta of Vietnam. Rat damage was simulated by making a 45° cut at the base of the rice tillers about 3–5 cm above the soil surface. 0% (control), 5%, 10%, 25% and 50% of the tillers were removed at the tillering (25 days after sowing, DAS), panicle initiation (43 DAS), flowering (72 DAS) and ripening (87 DAS) stages. The total number of mature tillers, immature tillers and percent filled grains, the weight of 1000 grains and grain yields were recorded. The rice crop completely compensated by increased tillering and yield for tillers damaged up to 50% at the tillering stage. However, the damage and yield loss were highly variable. The ability of the rice crop to compensate at later stages progressively reduced. The implications for managing rat damage to rice crops are (1) rodent control activities should be applied before 10% of tillers are damaged at the tillering stage, and (2) a well balanced nitrogen supply during the tillering stage could potentially assist the rice plants to better compensate for rat damage. [ABSTRACT FROM AUTHOR]

Abstract: Maize wallaby ear symptom (MWES) is induced by maize orange leafhopper (Cicadulina bipunctata) feeding and stunts the growth of maize. We examined the relationship between maize developmental stage and MWES occurrence and the effect of planting date on injury from MWES in western Japan. MWES was more pronounced on young maize, and rarely observed on maize older than the 5th or 6th leaf stage, indicating that younger maize is more susceptible to MWES. In a field experiment, early planting (before late July) avoided MWES and resulted in higher yields of forage maize, whereas MWES occurrence and yield loss gradually increased with late planting (from early to middle August) because of a rapid increase in C. bipunctata density during this period. Leaf and stem dry matter of the MWES-susceptible maize variety “3470” decreased together with increase in density of C. bipunctata, whereas leaf and stem dry matter of the MWES-tolerant maize variety “30D44” decreased little. These results indicate that earlier planting together with the use of MWES-tolerant varieties can significantly improve MWES control on forage maize. [ABSTRACT FROM AUTHOR]

Leguminous agroforestry (AF) species have been investigated and promoted in Malawi as a means to improve soil quality and maize (Zea mays) yields. Our objective was to determine whether AF systems' recommendations that solely consider impacts on average maize yields differ from those that include an analysis of production risk, profitability among different wealth groups and socioeconomic vulnerability. Employing participatory quantitative and qualitative on-farm research techniques, we investigated three AF-based maize/legume relay-cropping practices in southern Malawi. The perennial legumes included Sesbania sesban, Tephrosia vogeill and Cajanus cajan (pigeonpea). We found that AF species recommendations did diverge from those based solely on maximizing maize yields when incorporating risk, profitability and socioeconomic vulnerability as additional variables. For instance, the highest yielding system (the S. sesban/maize relay crop) was never recommended for the most vulnerable farmers based on the vulnerability analysis, and the cropping systems were often more profitable for the least vulnerable farmers than they were for the most vulnerable farmers. Cropping system recommendations based solely on obtaining the highest average maize yields would also have generally overlooked the economic and nutritional importance of pigeonpea, and the difficulty for the most vulnerable farmers to profit from fertilizers, potentially placing these farmers at greater risk. [ABSTRACT FROM AUTHOR]

The aim of this study was to find a simple measure for calf temperament discrimination, which can he useful as a selection criterion for on-farm French beef cattle breeding schemes. Behavioral records were registered at an average age of 5 and 7 mo, respectively, for 1,282 and 1,440 Limousin calves born in 24 French farms between August 2007 and April 2008. Measures were repeated for 810 calves at the 2 ages. The test procedure consisted of individually restraining the calves in a chute, then exposing them to a stationary human situated in front of the chute for 10 s. For every calf and each period of the test, the number of rush movements and the total number of movements were scored by visual appraisal using a continuous scale ranging from 0 (no movements) to 60 (continuous movements). Initial scores were also transformed to categorical scores and analyzed. Genetic correlation across ages were very high for all the traits (above 0.84 ± 0.20) suggesting that these traits are governed by the same pool of genes at the 2 ages. The corresponding phenotypic correlations were about 0.3 for all the measures. Heritabilities were moderate for all measures (from 0.11 to 0.31) with the total number of movements during weighing measured at 7 mo being the greatest. All the measures were highly correlated (from 0.73 ± 0.26 to 0.99 ± 0.02). Genetic correlation across sexes was not statistically different from 1. However, traits measured during weighing showed different genetic variance estimates for females and males. Similar results were obtained for the transformed categorical scores. According to these results, the total number of movements during weighing seems to be the most promising trait for on-farm genetic evaluation of French beef cattle temperament. [ABSTRACT FROM AUTHOR]

An Excel spreadsheet to estimate performance parameters for chisel plow-tractor combination during tillage process based on trained an artificial neural network was developed. The performance parameters include field and fuel efficiencies, draft, and required energy. The spreadsheet may be used as extension method for agricultural engineers for solutions of farm mechanization management problems during tillage process. The loading factor of the tractor was selected to be an optimizing criterion for the operating parameters. The spreadsheet offers an educational help and clarification to most of the affecting parameters on performance parameters. It was validated by comparing predicted performance parameters with the results obtained during field experiments. It has proven to be very user-friendly and efficient to meet the requirement. [ABSTRACT FROM AUTHOR]

Abstract: The objectives of this study were to disclose the mechanism of dry matter translocation and nitrogen (N) utilization under rice–wheat rotation and to propose optimum rate of N application. In a field experiment from 2007 to 2009 at the Changshu Agroecological Experiment Station, Chinese Academy of Sciences, Changshu, China, 4 levels of N fertilizer were designed during the growing period of rice and wheat. Among the N application treatments, N rates were 125 kg ha−1 + 94 kg ha−1 (rice season + wheat season) for N1, 225 kg ha−1 + 169 kg ha−1 for N2, 325 kg ha−1 + 244 kg ha−1 for N3, and zero N fertilizer applied (NO) served as the control. The results showed no significant increases in rice and wheat yield when the N application rates exceeded 225 kg ha−1 and 169 kg ha−1 in rice and wheat seasons, respectively. The dry matter accumulations at anthesis stages of rice and wheat were increased with the increment of N rate. However, the contributions of dry matter translocation from vegetative organs to grains before flowering were reduced in both crops when more N fertilizer was applied. The N agronomic efficiencies and physiological efficiencies in rice and wheat declined with the increase of N rate, but there was no significant difference between the N2 and N3 treatments. The N1 treatment had the largest average marginal productions for both rice (13.1 kg kg−1) and wheat (17.4 kg kg−1), followed by the N2 treatment (9.1 kg kg−1 for rice and 16.7 kg kg−1 for wheat), and the N3 treatment showed much smaller marginal productions than other treatments with only 3.1 kg kg−1 for rice and 2.4 kg kg−1 for wheat. Therefore, the N2 treatment could maintain relatively high translocation rates of dry matter, N use efficiencies and economic benefits in both rice and wheat. [Copyright &y& Elsevier]

Ex-situ collections of vegetatively propagated root crops are difficult to maintain in developing countries. On-farm conservation could be a solution but is more complex for vegetatively propagated than for sexually propagated species. In Vanuatu, a Melanesian archipelago where yam, taro, sweet potato and cassava are staples, a study was undertaken to develop an on-farm conservation system based on the geographic distribution of allelic diversity. Two years after the introduction of new varieties, a survey was conducted with 449 farmers located on 10 different islands. In order to evaluate on-farm conservation efficiency, qualitative and quantitative investigations were conducted and data were analysed. The conclusion was that farmers do enrich their varietal portfolios with introduced exotic genotypes thus broadening the narrow genetic bases of some species. Nevertheless, no local varieties were lost. Significant geographic distribution of clones of new varieties throughout the archipelago also took place via spontaneous, informal distribution to farmers' relatives. These encouraging results point to the potential impact of the geographic distribution of allelic diversity on small holders' varietal portfolios. On-farm conservation appears to be an appropriate strategy for the conservation of root crop germplasm diversity in Vanuatu. Potential applications for transfer of the methodology to other locations are discussed. [ABSTRACT FROM AUTHOR]

Field experiment conducted during kharif seasons of 2004 and 2005 at Kittur Rani Channamma College of Horticulture, Arabhavi, Karnataka revealed that closer planting (60 cm x 20 cm) of pashanbhedi recorded significantly higher gross (Rs 82,083/ha) and net returns (Rs. 56,822/ha), and B: C ratio (3.25) than wider spacing levels (60 cm x 30 cm, 75 cm x 20 cm and 45 cm x 30 cm). Among the time of harvest, harvesting the crop at 180 and 160 DAP recorded significantly higher B: C ratio (3.17 and 3.07, respectively), and gross (Rs.76,188 and 73,438/ha, respectively) and net returns (Rs. 52,279 and 49,609/ha, respectively) than 140 DAP. The interaction effects showed higher B: C ratio in the treatment combination 60 cm x 20 cm - harvesting at 180 DAP (3.67) and 60 cm x 20 cm -harvesting at 160 DAP (3.62). Thus, the spacing of 60 cm x 20 cm and harvesting pashanbhedi at 160 DAP can be recommended for higher returns under irrigated condition. [ABSTRACT FROM AUTHOR]

Resistance to leaf rust ( Puccinia triticina Eriks.) is a main objective for durum wheat ( Triticum durum Desf.) breeding. Association mapping on germplasm collections is now being used as an additional approach for the discovery and validation of major genes/QTLs. In this study, a collection of 164 elite durum wheat accessions suitable for association mapping has been tested for leaf rust response at the seedling stage and under field conditions (adult plant stage). Seedling tests were carried out with 25 selected isolates from durum wheat, bread wheat and triticale, while field experiments were carried out in artificially inoculated plots in Italy and in Mexico. The collection has been profiled with 225 simple sequence repeat (SSR) loci of known map position and a PCR assay targeting Ppd-A1. Associations showing highly consistent experiment-wise significances across leaf rust isolates and field trials were mainly detected for the 7BL distal chromosome (chr.) region (harbouring Lr14 from cultivar Llareta INIA and QLr.ubo-7B.2 from cultivar Creso) and for two chr. regions located in chrs. 2A and 2B. Additionally, isolate-specific associations and/or associations with smaller effects in the field trials were identified in most of the chromosomes. The chr. 7BL distal region was investigated in detail through haplotyping with 15 SSR markers, revealing that the Creso and Llareta INIA alleles are identical by descent at 6 adjacent SSR loci in the most distal 7BL region spanning 8 cM. Association mapping allowed us to further refine the map location of the Lr14/ QLr.ubo-7B.2 resistance gene to the most distal region of the linkage group, tagged by Xcfa2257.2, Xgwm344.2 and Xwmc10. The resistant haplotype is present in a number of accessions (ca. 15% of the accessions included in the collection) from the Italian, CIMMYT and ICARDA breeding programmes. Therefore, this chr. 7BL region can be considered as the most important source of resistance to leaf rust currently exploited by durum breeders in the Mediterranean areas. Furthermore, the field trials at the adult plant stage allowed us to identify marker associations (e.g. chrs. 2BL and 3BS, proximal regions; chr. 7BS, distal region) which suggest the presence of minor QTLs for slow-rusting resistance. [ABSTRACT FROM AUTHOR]

One of the objectives of the present study is to gain a deeper understanding of the heat transfer mechanisms that control the spread of wildfires. Five experimental fires were conducted in the field across plots of living vegetation. This study focussed on characterising heat transfer ahead of the flame front. The temperature and heat flux were measured at the top of the vegetation as the fire spread. The results showed the existence of two different fire spread regimes that were either dominated by radiation or governed by mixed radiant-convective heat transfer. For plume-dominated fires, the flow strongly responds to the great buoyancy forces generated by the fire; this guides the fire plume upward. For wind-driven fires, the flow is governed by inertial forces due to the wind, and the fire plume is greatly tilted towards unburned vegetation. The correlations of the temperature (ahead of the flame front) and wind velocity fluctuations change according to the fire regime. The longitudinal distributions of the radiant heat flux ahead of the fire front are also discussed. The data showed that neither the convective Froude number nor the Nelson convection number - used in the literature to predict fire spread regimes - reflect the observed behaviour of wind-driven fires. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the effects of plant growth regulator (PGR) (no PGR, trinexapac-ethyl, and paclobutrazol) and N fertilizer (zero N, an average of 37 kg N ha−1 month−1, 6 and 12 kg N ha−1 week−1) on soil organic C (SOC) and soil N in creeping bentgrass ( Agrostis stolonifera L.) fairway turf. After 4 years of field experiments soil samples were obtained from soil depths of 0–2.5, 2.5–5, 5–7.5, 7.5–10, 10–15, 15–20, and 20–30 cm. Soil bulk density, SOC, total N, NO–N, and NH–N concentrations were determined. Paclobutrazol and trinexapac-ethyl application increased SOC. The 37 kg N ha−1 month−1 application increased SOC at the 0–2.5 cm depth with both PGRs. When paclobutrazol was used, N fertilizer always increased SOC; however, the greatest increase was observed with the 12 kg N ha−1 week−1 application when compared to other rates, inversely related to the NH–N concentration. Nitrogen application increased soil total N and NO–N in the upper three depths. The application of PGRs and N fertilizer to creeping bentgrass fairway turf is an effective strategy for promoting C sequestration. [ABSTRACT FROM AUTHOR]

Abstract: We used a farm-level modeling approach to estimate on-farm compliance costs and environmental effects of a grassland extensification scheme in the district of Ostprignitz-Ruppin, Germany. The behavior of the regional farm population (n =585) consisting of different farm types with different production orientations and grassland types was modeled under the presence and absence of the grassland extensification scheme using the bio-economic model MODAM. Farms were based on available accountancy data and surveyed production data, while information on farm location within the district was derived from a spatial allocation procedure. The reduction in total gross margin per unit area was used to measure on-farm compliance costs. A dimensionless environmental index was used to assess the suitability of the scheme to reduce the risk of nitrate-leaching. Calculated on-farm compliance costs and environmental effects were heterogeneous in space and farm types as a result of different agricultural production and site characteristics. On-farm costs ranged from zero up to almost 1500Euro/ha. Such high costs occurred only in a very small part of the regional area, whereas the majority of the grassland had low on-farm costs below 50Euro/ha. Environmental effects were moderate and greater on high-yield than on low-yield grassland. The low effectiveness combined with low on-farm costs in large parts of the region indicates that the scheme is not well targeted. The soft scheme design results from an attempt to achieve environmental and rural development objectives with only one scheme. Improving the efficiency of the scheme would require designing separate instruments for the two distinct objectives. This is in line with the Tinbergen rule, which states that consistent economic policy requires that the number of instruments equals the number of targets. [Copyright &y& Elsevier]

A field experiment was conducted at Adaptive Research Farm, Vehari, Pakistan during 2006-07 to evaluate the effect of different seed rates and row spacings on the growth and yield of wheat (Triticum aestivum L.). Four levels of seed rates (125, 150, 175 and 200 kg/ha) and three row spacings (11.25, 15.0 and 22.5 cm) were tried (cv. Uqab 2002), The results showed that seed rate of 150 kg gave higher grain yield (4.10 t/ha). Among row spacings 22.5 cm performed better (3.96 t/ha) as compared to other spacings (3.82-3.87 t/ha). Interaction effect of seed rates and row spacings was non-significant. [ABSTRACT FROM AUTHOR]

Abstract: The applicability of conservation agriculture (CA) in sub-Saharan Africa (SSA) is poorly documented. In the “Nord” and “Extrême-Nord” provinces of Cameroon, in a 2-year rotation between a cereal (maize or sorghum) and cotton, conventional techniques were compared with CA. The study was conducted from 2001 to 2006 in 662 plots in 243 farmers’ fields. Cereal treatments compared were conventional management techniques and CA consisting in the production of mulch using cover crops (Brachiaria ruziziensis, Crotalaria retusa, Dolichos lablab, Mucuna pruriens, Vigna unguiculata) intercropped within the cereal. In the “Extrême-Nord” province up to 9.7tha−1 of vegetative biomass was produced in the CA plots with sorghum and cover crops against up to 4.8tha−1 for sorghum alone in conventional plots. In the “Nord” province maize+cover crops produced up to 5.2tha−1 of biomass against up to 2.5tha−1 for maize alone. In both provinces, the cereal grain yields were equivalent or higher in CA compared to conventional plots. In 18 fields of the “Extrême-Nord” province the mulch remaining the year after sorghum+ B. ruziziensis is mainly comprised between 3tha−1 and 5tha−1. Cotton treatments compared were T (tillage), NT (no tillage), and NTM (no tillage with mulch). In both provinces these treatments differed in soil cover, number of localized herbicide sprays used, ridging, and amount of nitrogen fertilizer used. In the “Extrême-Nord” province treatments differed also for the number of weeding and the date of the first weeding. In the “Extrême-Nord” province cotton yields were 12% lower for T and 24% lower for NT than for NTM. Cotton yields were regressed on crop husbandry indicators and used inputs. After a manual backward removal in a multiple linear regression respectively no parameters were found to significantly influence yield for T, only one parameter for NT, the number of herbicide sprays used at sowing, and three parameters for NTM: difference between heavy clay and silty loam, application of NPK fertilizer, sowing date. In the “Nord” province no difference in cotton yield was observed between T, NT and NTM. The flowering period was longer for NTM vs NT in the “Extrême-Nord” and the “Nord” provinces and NTM vs T in the “Nord” province, respectively 13, 9 and 8 days. Although we show that CA techniques can have benefits at field level, further studies are needed to assess their suitability at farm and village levels. [Copyright &y& Elsevier]

Adequate boron (B) nutrition may decrease concentrations of phenolic compounds and enhance structural integrity and lignification in plants, compared with suboptimal B. This could affect decomposition in areas where B deficiencies are common. The mass loss and changes in element concentrations in Norway spruce needle litter were studied with combinations of litter from high-B and low-B trees, incubated for 29 months, in either B fertilised or control plots without B addition. The litter originated from the same Norway spruce field experiments. Additionally, the field experiments included long-term N and P treatments. Initially, lowest lignin concentrations were found in Norway spruce litter from the treatment P and particularly in the combination B + P, and highest in the B + N fertilised plots. The mass loss of Norway spruce litter was not affected by the treatments. However, Blitter increased Cu accumulation. The litter from the B + P fertilised plots accumulated considerably more Al, Ca, S and Zn than the other treatments, whereas B together with N reduced the remaining amounts of these elements. Reduced nutrient release from litter may have far-reaching consequences on nutrient cycles in forests. [ABSTRACT FROM AUTHOR]

With appropriate management controls and statistical designs, on-farm trials are an increasingly valuable research tool. On-farm trials can speed up technology adoption, particularly with those studies requiring large numbers of animals. Useful designs include longitudinal (pen vs. pen) trials, in which pen is the experimental unit, and crossover or switchback designs, in which treatments are imposed on a schedule over 1 or more experimental groups. A paired-herd design has been used, in which herds are the experimental units in a crossover trial. Others have published similar studies, including a multisite crossover design that used 35 dairy farms to compare milk responses with a protein source by using individual cow records to evaluate differences in milk production. Recently, statistical process control (SPC) techniques have been used to evaluate management changes by using repeated measures on the farm. Although a drawback to SPC may be the lack of traditional statistics to test differences (i.e., the lack of a control group), standard run rules are used to demonstrate with statistical certainty that a process or variable has changed, or to characterize a seasonal change. With SPC, the inference is limited to the herd or group of animals being monitored. Meta-analysis techniques are powerful tools used to combine results from many similar trials in which the response of interest is either small (i.e., continuous variables) or of low frequency (i.e., discrete variables). Meta-analysis can be used to segment a database so as to validate and compare trial methods or to investigate publication bias. Additional design concerns for reproduction studies include the need for adequate numbers of observations and planning for the lag time between an experimental treatment and response measurement (e.g., confirmation of pregnancy). [ABSTRACT FROM AUTHOR]

The hydrant pressure head in an on-demand water distribution system can be subject to high fluctuation depending on the discharge flowing inside the pipes, with consequent impacts on the performance of on-farm irrigation systems. In this work, an Italian water distribution system was analyzed using the AKLA model at upstream discharges of 1,200 and 600 L·s-1 to estimate the range of hydrant pressure variation. A computer model was developed, calibrated, and used to evaluate the performance of a drip irrigation system by relating the on-farm network with the hydrant characteristic curve at a certain operating status. The flow regulator within the hydrant played an important role in stabilizing the performance of the network at hydrant pressures higher than 27 m. At lower hydrant pressures, to apply the same amount of water, irrigation time must be extended by 17 and 95% for pressure heads of 20 and 12 m, respectively. These approaches described have great utility to ensure adequate irrigation management when water is delivered by pressurized on-demand systems. [ABSTRACT FROM AUTHOR]

This paper presents the results of 2 experiments: an incubation experiment and a subsequent field experiment. An incubation experiment was set up in order to determine the mineralization potential of different organic materials (OMs) (well–rotted farmyard manure [FTM], guano [G], soybean seed [S], and forage pea seed [P]), the kinetics of mineral nitrogen (N) release, and the correlation between OM content and the quantity of mineralized N. The results of the incubation experiment were checked under field conditions in which different OMs were used as N sources for lettuce (Lactuca sativa L.). The highest mineralization rate constant k (0.127 day-1) and net mineralization rate (NM) (76.37% of total applied N) were obtained with G, and the lowest k (0.098 day-1) and NM (30.12% of total applied N) were obtained with FYM. In the field experiment in 2007 and 2008 we applied different OM sources that contained the same amount of potentially mineralizable N (40 and 35 kg N ha–1, respectively), calculated on the basis of k and NM. The use of OMs increased the concentration of mineral N in the soil and increased the yield of fresh lettuce. Nitrate content in the fresh lettuce was within acceptable limits both years (<2500 mg kg–1). Total N in the above–ground parts of lettuce ranged from 44.38 kg N ha-1 (Ø, treatment without fertilization) to 67.45 kg N ha-1 (S) (2–year average). The results show that when determining the quantity of OM to apply it is necessary to take into account the quantity of potentially mineralizable N in order for the plants to use N as efficiently as possible, to regulate the nitrate content in fresh lettuce, and to control the quantity of residual mineral N in the soil at the end of the vegetation period. [ABSTRACT FROM AUTHOR]

Crop species and their varieties vary in phosphorus (P) requirements for optimum production and response to P application. As crop recovery of added P often ranges from 10 to 40%, the rest accumulates in soil and may create potential for P leaching, depending upon the soil characteristics, duration of P applications, and cropping systems. Accumulation and distribution of Olsen P (plant-available labile P), total inorganic P, and total organic P were investigated in soil profiles of three field experiments differing in rate (9-44 kg P ha-1), frequency (applied once or twice annually), and duration (4-34 years) of fertilizer P applications, crop rotations, soil characteristics, and irrigation pattern (upland irrigated and flooded-rice crop) in a subtropical region. Profile samples were collected from soil depths of 0-15, 15-30, 30-60, 60-90, 90-120, and 120-150 cm of different treatments in these experiments and analyzed for different forms of P and soil characteristics. The results revealed that (i) annual applications of fertilizer P either to one crop (alternative-applied P) or to both crops (cumulative) led to the accumulation of residual fertilizer P in the form of Olsen P, varying from 44 to 148 kg P ha-1, and the magnitude of accumulation was proportional to applied fertilizer P rate, frequency, and duration; (ii) majority of residual fertilizer P accumulated as inorganic P (74-89%) followed by organic P (11-26%) and Olsen P (9-19%), illustrating that the inorganic P pool is a major sink for fertilizer P; (iii) application of fertilizer nitrogen (N) and potassium (K) alone or in combination with fertilizer P did not affect residual fertilizer P accumulation in soil profile; (iv) incorporation of farmyard manure enhanced the P enrichment of soil profile; (v) irrigation pattern, soil pH (7.1-7.7), and calcium carbonate (CaCO3) (trace-0.33%) did not influence P movement to deeper soil layers; silt, clay, and soil organic C (SOC) showed strong relationships with Olsen P (r = 0.827, 0.938, and 0.464, P < 0.01) and enhanced the retention of labile P in the plow layer; and (vi) only 6-29% total residual P moved beyond 30 cm deep in fine-textured soils under 22-year rice (Oryza sativa L.)-wheat (Triticum aestivum L.) and 34-year maize (Zea maize L.)-wheat rotations, whereas 41, 27, 20, 9, and 3% were located in soil layers 0-30, 30-60, 60-90, 90-120, and 120-150 cm deep, respectively, in coarse-textured soil profile under 4-year peanut (Arachis hypogaea L.)-sunflower (Helianthus annuus L.) field. These findings confirmed that interplay between the fertilizer P management (alternative vis-a-vis cumulative P application and optimal vis-a-vis excessive rates of fertilizer P in different crop rotations), amount of labile P accumulated in soil profile, and soil characteristics (silt, clay, and SOC) largely controlled the downward movement and resultant potential for P leaching in subtropical irrigated soils. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) sorption and desorption characteristics by Alfisols from different land uses were examined, and the relationships between soil and sorption/desorption characteristics were investigated. Adsorption studies were done using Cd concentrations (0-100 mg Cd kg-1) in 0.01 M CaCl2. The Cd sorbed by the soils was then subjected to two desorption runs. The soils' adsorption conformed to Freundlich and Langmuir equations. The amount of Cd sorbed by the soils varied. Two desorption runs detached more than 95% of sorbed Cd, but the first accounted for more than 80% of the total. Desorption of Cd in degraded soils was more than in soils from other land uses. The amount of Cd desorbed correlated with amount applied (r = 0.90**), solution concentration (r = 0.83**), and amount sorbed (r = 0.70**). A positive relationship exists between the adsorption maxima of the soils and soil organic matter (r = 0.13, p = 0.87). The relationship between amount of Cd desorbed and sorbed is quadratic for all the soil. [ABSTRACT FROM AUTHOR]

To compare the effects of the system of rice intensification (SRI) on yield, water use efficiency, and microbial biomass in associated rice soils, a field experiment was conducted in 2004 at the Agriculture Experimental Farm of Zhejiang University in Zhejiang Province, China. The treatments evaluated were traditional flooding (TF) vs. SRI cultivation methods. Grain yield in the SRI treatment was 26.4% greater than that in the TF treatment, reducing water use by 461.5 mm. Compared to TF, SRI increased water use efficiency by 91.3% and irrigation water use efficiency by 194.9%. Soil microbial indicators during the rice-growing season also diverged between TF and SRI. Microbial biomass C (MBC) was in the range of 101-196 mg kg-1 for TF vs. 113-224 mg kg-1 for SRI; microbial biomass N (MBN) was in the range of 14-33 mg kg-1 for TF vs. 28-53 mg kg-1 in SRI. Compared to TF, SRI significantly increased both MBC and MBN, regardless of sampling date. [ABSTRACT FROM AUTHOR]

Cation mobility in acidic soils with low organic-matter contents depends not only on sorption intensity but also on the solubility of the species present in soil solution. In general, the following leaching gradient is observed: potassium (K+) > magnesium (Mg2+) > calcium (Ca2+) > aluminum (Al3+). To minimize nutrient losses and ameliorate the subsoil, soil solution must be changed, favoring higher mobility of M2+ (metal ions) forms. This would be theoretically possible if plant residues were kept on the soil surface. An experiment was conducted in pots containing a Distroferric Red Latosol, with soil solution extractors installed at two depths. Pearl millet, black oat, and oilseed radish residues were laid on the soil surface, and nitrogen (as ammonium nitrate) was applied at rates ranging from 0 to 150 mg kg-1. Corn was grown for 52 days. Except for K+ and ammonium (NH4 +), nitrogen rates and plant residues had little effect upon the concentrations and forms of the elements in the soil solution. Presence of cover crop residues on soil surface decreased the effect of nitrogen fertilizer on Ca leaching. More than 90% of the Ca2+, Mg2+, and K+ were found as free ions. The Al3+ was almost totally complexed as Al(OH3)0. Nitrogen application increased the concentrations of almost all the ions in soil solution, including Al3+, although there was no modification in the leaching gradient. [ABSTRACT FROM AUTHOR]

Available micronutrient status of zinc, copper, manganese, and iron (Zn, Cu, Mn, and Fe) in surface soil samples under a rice-wheat system collected from farmers' fields in 40 districts representing different agroclimatic zones of the Indo-Gangetic Plain (IGP) were determined. The selection of farmers, villages, blocks, and districts within an agroclimatic zone was made on the basis of a multistage statistical approach. In Trans-Gangetic Plains, the diethylenetriaminepentaacetic acid (DTPA)-extractable Zn ranged from 0.11 to 5.08, Cu ranged from 0.22 to 4.72, Mn ranged from 2.9 to 101.2, and Fe ranged from 1.05 to 97.9 mg kg-1. In the Upper Gangetic Plains, the DTPA-extractable Zn ranged from 0.04 to 2.53, Cu ranged from 0.06 to 4.32, Mn ranged from 11.1 to 421.0, and Fe ranged from 3.48 to 90.2 mg kg-1. In the Middle Gangetic Plains, the DTPA-extractable Zn ranged from 0.17 to 8.60, Cu ranged from 0.09 to 7.80, Mn ranged from 3.0 to 155.1, and Fe ranged from 9.22 to 256.7 mg kg-1. In the Lower Gangetic Plains, the DTPA-extractable Zn ranged from 0.04 to 3.46, Cu ranged from 0.21 to 4.38, Mn ranged from 9.54 to 252.2, and Fe ranged from 3.60 to 182.5 mg kg-1. The intensively cultivated Trans-Gangetic transect representing the midplain and Siwalik had more available micronutrients than the arid plain. Midplain and arid plain showed 17 to 20% of soil samples were low to medium in Zn and 5 and 8% were low in Fe. In the Upper Gangetic Plains, only 25% samples were deficient in Zn, especially in central and southwest plains. In the Middle Gangetic Plains, 20 to 30% of samples were deficient in Zn, and very few samples were deficient in other micronutrients. In the Lower Gangetic Plains, a majority of the samples were medium to high in micronutrients except in Barind and Rarh Plains where 30% of samples were deficient in Zn. In the Lower Gangetic Plains, the available micronutrients were plentiful. Available micronutrients increased with increase in organic C content and decreased with increase in sand content, pH, and calcium carbonate. These soils are alluvial in nature, and there was no definite pattern of micronutrient distribution with depth in the profile. However, there was more accumulation in the Ap horizon than in the B horizon. [ABSTRACT FROM AUTHOR]

The relationships between potential laboratory indices for plant-available nitrogen (N) and the plant N uptake in a pot experiment with ryegrass were assessed for 13 mineral soils and 2 peat soils. The methods included aerobic soil incubation, soil incubation in a bioreactor, hot potassium chloride (KCl)-extractable mineral N, 0.01 M calcium chloride (CaCl2)-extractable N, and N loss at heating. The indices for total plant-available N accounted for 63-93% of the variance in N uptake in a statistical analysis with all soils (n = 15) and 27-89% for the mineral soils (n = 13). Most indices were not a direct quantitative measure of the plant N uptake. The N mineralization indices accounted for 57-86% of the variance in N mineralization for all soils and 5-50% for the mineral soils. Hot KCl-extractable mineral N and 0.01 M CaCl2-extractable N were the most promising rapid indices for plant-available N. [ABSTRACT FROM AUTHOR]

Recycling organic waste in agricultural soils is a valid solution. We performed short-term experiments to investigate the fate of urban sludge and composts, in mine spoils, cultivated or uncultivated, and reclaimed soils located in Florence and Milan, Italy. The samples, either treated or untreated, were fractionated by density into light (<1.63 Mg m-3) and heavy (>1.63 Mg m-3) fractions. The fractions were analyzed for total carbon (C) and nitrogen (N) contents and for δ 13C and δ 15N isotopes, and they were characterized by 13C NMR spectroscopy. Treatment increased the heavy fraction. The addition of sludge in the Florence area acts in synergy with the cultivation, increasing the light fraction (LF). In the Milan area, the LF tends to be decomposed and apparently transformed into HF. The addition of amendments or cultivation enhances the decomposition with release of carbon dioxide. For future research, we suggest lengthening the time of the experiments to integrate climatic variations. [ABSTRACT FROM AUTHOR]

The different responses of two populations of Suaeda salsa (Linn.) Pall. (saline seepweed) from an intertidal zone and a saline inland zone to salinity [1 or 500 mM sodium chloride (NaCl)] and nitrogen [N; 0.05, 1, or 10 mM nitrate (NO3 -)-N] were investigated. Greater NO3 --N supply (10 mM) increased shoot dry weight for the two populations of S. salsa, especially for S. salsa from the saline inland zone. Greater NO3 --N supply (10 mM) increased the concentrations of chlorophyll and carotenoid in leaves and the NO3 - and potassium (K+) concentrations in shoots for both populations. Greater NO3 --N supply (10 mM) increased shoot Na+ in S. salsa from the intertidal zone. In conclusion, S. salsa from the saline inland zone is more responsive to NO3 --N supply than the intertidal population. Greater NO3 --N supply can help the species, especially the intertidal population, to grow and to mediate ion homeostasis under high salinity. [ABSTRACT FROM AUTHOR]

The supply of nutrients to plants from organic growing media depends on mineralization as the addition of inorganic nutrients is forbidden in certified organic systems. The objective of this study was to determine the relationship between total phosphorus (P), extractable (Olsen's) P, organic P, and biomass P in growing media and uptake of P by ryegrass. Three proprietary products were used alone and combined in 1:2 and 2:1 proportions to give nine growing media. Perennial ryegrass (Lolium perenne L. cv. 'Choice') was irrigated with a modified Hoagland's solution minus P, and the shoots were harvested after 28, 56, and 84 days. There was no significant correlation between the amounts of the different forms of P in the growing media and ryegrass dry weight or P concentration in harvested grass. However, total ryegrass P uptake was significantly positively correlated with initial total P and organic P in the growing media. [ABSTRACT FROM AUTHOR]

Field experiments were conducted on rice (cv 'IET 4094') in an Aeric endoaquept (pH 7.2) to evaluate the various zinc (Zn) extractants in lowland rice soil under the influence of Zn sulfate and chelated Zn. The diethylenetriaminepentaacetic acid (DTPA), 0.1 N hydrochloric acid (HCl), and 0.05 N HCl-extractable Zn concentrations in soil increased initially up to the Z29 stage of crop growth when Zn was applied as a single basal source, being greater with Zn ethylenediaminetetraacetic acid (Zn-EDTA) compared to zinc sulfate (ZnSO4) application. Among the various extractants, the performance of 0.1 N HCl in extracting Zn was better than the other two extractants and followed the trend 0.1 N HCl > 0.005 M DTPA > 0.05 N HCl. The greatest increase in grain and straw yield of rice was 37.8 and 20.4%, respectively, over the control in the treatment T7 (1 kg Zn ha-1 as Zn-EDTA at basal). [ABSTRACT FROM AUTHOR]

Abstract: In intensive arable areas, field margins can constitute boundary biotopes that are valuable for natural resource conservation. In order to analyse the potential for implementing more field margin measures, 865 responding farmers in intensive arable areas in three German federal states were surveyed. Determinants of their willingness to participate in field margin measures were analysed by binary logistic regression. The farmers were asked about the optimal design of field margins, and these designs are discussed within the context of nature conservation goals. The results show that farmers implement field margins less often if they are risk-averse. Farmers already implementing grassland environmental measures and mulch seeding or extensification measures with regards to herbicide and fertiliser reductions on arable land more often adopt field margin measures. Regarding the design of field margins, farmers’ preferences hardly differ between the federal states, and they do not significantly conflict with nature conservation needs in intensive arable areas. The main fear is the risk of weed spreading. Therefore, farmers prefer sown field margins, mown at least once a year and treated with restricted herbicide applications. Certain features, such as seed mixture, mowing date and plant protection measures, could be adapted in order to minimise conflicts with nature conservation objectives. [Copyright &y& Elsevier]

Does the intensification of agriculture reduce cultivated areas and, in so doing, spare some lands by concentrating production on other lands? Such sparing is important for many reasons, among them the enhanced abilities of released lands to sequester carbon and provide other environmental services. Difficulties measuring the extent of spared land make it impossible to investigate fully the hypothesized causal chain from agricultural intensification to declines in cultivated areas and then to increases in spared land. We analyze the historical circumstances in which rising yields have been accompanied by declines in cultivated areas, thereby leading to land-sparing. We use national-level United Nations Food and Agricultural Organization data on trends in cropland from 1970-2005, with particular emphasis on the 1990-2005 period, for 10 major crop types. Cropland has increased more slowly than population during this period, but paired increases in yields and declines in cropland occurred infrequently. both globally and nationally. Agricultural intensification was not generally accompanied by decline or stasis in cropland area at a national scale during this time period, except in countries with grain imports and conservation set-aside programs. Future projections of cropland abandonment and ensuing environmental services cannot be assumed without explicit policy intervention. [ABSTRACT FROM AUTHOR]

Abstract: Experiments were conducted at irrigated and rainfed lowland rice sites in Bangladesh to assess the performance of management practices that have become known as the System of Rice Intensification (SRI). At a research station, SRI management principles such as seedling age, plant spacing, application of organic manure, seedling densities, duration of planting, planting shape and time of planting were evaluated under SRI management as compared to previously established Best Management Practices (BMPs). In on-farm trials, SRI was compared with BMP on 40 farmers’ fields. Nutrient inputs and water management in BMP and SRI treatments were kept at comparable levels. Seedling age, ranging from just sprouted seed to 40-day-old seedlings, had no effect on grain yield in the winter season. In a plant spacing experiment subject to SRI, the highest and lowest grain yields of 7.82 and 5.41tha−1 were obtained with spacing of 25cm×15cm (narrow) and 40cm×40cm (wide), respectively. In SRI, seedling density (1–2 seedlings per hill), planting durations (≤15min to 1–3h after uprooting) or root placement (L-shape and J-shape) had no effect on grain yield. With regard to time of planting, the highest grain yields were observed with transplanting in the 3rd week of December, with no difference between SRI and BMP management systems. In on-farm trials, BMP gave significantly higher grain yield compared to SRI and farmers’ practice in a triple-cropped area, but grain yields were similar with SRI in a double and single-cropped area when spacing was narrow. The highest profit was obtained with BMP followed by SRI and farmers’ practice in the single-cropping area. Major findings from this study are that under comparable levels of net nutrient input and water management (i) well-implemented BMPs for rice are more efficient for producing high yields than SRI and (ii) there is no intrinsic yield advantage of SRI that could be caused by its individual crop management techniques or some unknown synergism of the different SRI practices proposed. [Copyright &y& Elsevier]

Purple phototrophic bacteria (PPB) are thought to be crucial in the nutrient cycling of rice field. However, it remains unclear how PPB would respond to the climate change associated with the projected atmospheric CO2 in the future. A factorial design of field experiments was set up with two levels of atmospheric CO2 concentration (350 and 550 μmol mol−1) and N application rate (150 and 250 kg N ha−1) to investigate the abundance and composition changes of PPB in rhizospheric and bulk soils in response to the rising atmospheric CO2 concentration. Based on denaturant gradient gel electrophoresis (DGGE) analysis of pufM gene encoding the M subunit of anoxygenic PPB light reaction center, elevated CO2 appeared to enhance the biodiversity of PPB in flooded paddy soils. This was further supported by canonical correspondence analysis (CCA) of DGGE fingerprinting pattern of pufM genes in paddy soils as well as Shannon diversity indices. Real-time quantitative PCR analysis of pufM gene further indicated that PPB abundance was stimulated by elevated CO2 in bulk soil, while the contrasting result was observed in rhizospheric soil. Our result for the first time demonstrated that elevated CO2 enhanced the biodiversity of PPB within α and β subdivisions of Proteobacteria. [ABSTRACT FROM AUTHOR]

Abstract: This paper develops a conceptual framework for choosing the most cost-effective intervention along the supply chain to improve food safety. This framework identifies both the initial level of on-farm infection and the potential for new infection post farm-gate as key parameters influencing the relative effectiveness of on-farm and abattoir interventions. In addition, the potential for cost economies of scale in implementing interventions at abattoir compared to on-farm is shown to be a further factor determining the relative cost-effectiveness of these interventions. Overall, it is suggested by the analysis in this paper that successful abattoir interventions will typically be more cost-effective than successful on-farm interventions. These findings are consistent with existing case study evidence. [Copyright &y& Elsevier]

The experiment was conducted on four species of Tassar Resham Keet (Aentheria mailitta D.) i.e. Daba, Sukinda, Bhandara and Teera in climate of Ranchi for studying annual breeding. Alalysis of data revealed that annual breeding is affected by change of residence place. Development of larvees depend on annual breeding alongwith adoption which is affected by light duration. Light duration was calculated on the basis of altitude. It is concluded from the study that adoption and annual breeding is affected by height from sea level and change in altitude of residence place. [ABSTRACT FROM AUTHOR]

The experiment was conducted at farmers field Near Regional Agriculture Reserach Centre Hazaratpur, Firozabad of Chandra Shekhar Azad University of Agriculture and Technology Kanpur during the consicutive Kharif season 2007-08 and 2008-09 to find the effect of inorganic chemical fertilizers with organic, source of nutrients on growth and yield of Okra variety Azad Bhindi-1. The results revealed that the integrated application of 75% RDF with varmicompost @ 6 t/ha gave significantly higher marketable fruit yield (99.80 q/ha), over control which was closely followed by the treatment namely 50% RDF + Vermicompost @ 6 t/ha (92.45 q/ha), 75% RDF + Neem cake @ 3.0 t/ha (80.30 q/ha). Integrated application of either 50% or 75% RDF with Vericompost @ 6t/ha or neem cake @ 3.0q/ha, resulted in significant improvement in vegetative and fruit characters in Okra over control. Thus for better vegetative growth, fruit attributes and marketable yield in okra, integrated use of inorganic and organic sources of nutrient supply was formal better than the other treatment application. [ABSTRACT FROM AUTHOR]

Studies on growth and development of pevendi ber (Ziziphus mauritiana Lank.) of Jhansi Uttar Pradesh Showed that the fruit growth in term of fruit weitght, volume, fruit length and diameter presented a double sigmoid curve. The interval between fruit setting and maturity was 130 days. It was found that, total solible solids, titrable acidity reducing sugar and total suger in fruit in pulp increased towards maturity. Ascorbic acid content increased and decreased as the fruit matured. [ABSTRACT FROM AUTHOR]

A field experiment was conducted at Bharari Jhansi (U.P.) of Chandra Shekher Azad University of Agriculture and Technology Kanpur, during consecutive Rabi season 2004-05 and 2005-06 to study the effect of time of sowing and specing on seed yield of pea CV. Azad P-3. First fort night of November (12 Nov.) was highest seed yield (18.7 q/ha) under 30 cm specing with thining distance between plant to plant 10 cm. [ABSTRACT FROM AUTHOR]

The field experiment was conducted on integrated nutrition of NPK, Zn, Mo and FYM along with rhizobium and PSB of soybean variety JS, 90-41, during kharif 2005 at JNKVV, Jabalpur. Result showed conspicuous and significant effect on yield, quantity and quality of soybean. The highest grain yield obtained with the integrated use of input resource in T9 (16.9 q ha-1) than lowest grain yield T3. Like wise, straw yield in this combination was found to be (41.60 q ha-1) and minimum at T3 (19.20 q ha-1). The quality of the produces like wise oil ocntent and protein content indicates that the impact was quite apparent in different sub treatments in grain of soybean. The value of oil content and oil production ranged between 15.0 to 19.9% and 169-470 kg q ha-1 respectivel. Similarly the production of protein ranged between 270-699 kg q ha-1 in grain of soybean. They were statistically significant with each other. [ABSTRACT FROM AUTHOR]

The objectives of this research were to estimate the genetic divergence among genotypes of bush snap bean with based on morphoagronomic descriptors and evaluation of resistance to bacterial wilt; to determine the relative importance of the distinguishing traits of genotypes and to indicate potential parents to establish a snap bean breeding program for resistance to bacterial wilt. Two experiments were conducted, the first in the field and the second in a greenhouse, both with 15 genotypes in a randomized block design with three replications. Seven traits were studied in the field experiment: days to flowering; days to harvest; mean pod length; number of pods; number of pods per plant; total pod weight and number of seeds per pod. In the greenhouse, the reaction of bacterial wilt was assessed based on two variables, one based on a descriptive grade scale and the other based on the Area Under the Disease Progress Curve (AUDPC). For the evaluation of genotype resistance to bacterial wilt the isolate Feij - 2634 of Curtobacterium flaccumfaciens pv. flaccumfaciens was inoculated. The statistics of pseudo t² indicated the formation of four groups by the UPGMA method, the same number of groups as indicated by the use of canonical variables. The traits that contributed most to genetic divergence were days to harvest, pod length, pod diameter and AUDPC. [ABSTRACT FROM AUTHOR]

The article discusses a study on soil erodibility under natural and artificial rainfall conditions and compares the nomograph estimation of soil erodibility with the observed soil erodibility. It cites the study area where the soil erodibility field experiment was done, namely the Ballowal Saunkhri-1 and Ballowal Saunkhri-2 under natural rainfall conditions and the addition of Kokowal Majari for artificial rainfall conditions. It suggests the use of modified nomograph for estimating soil erodibility that is more dependent on aggregation.

The relationship between Hagberg falling number and grain size was investigated in field-grown winter wheat varieties. Data was obtained for all varieties included in the UK Recommended List from 1997 to 2007. Overall, a negative association was found between thousand grain weight and Hagberg falling number. The negative association was detected between varieties in all years and within varieties in the majority of cases. Detailed Recommended List data from 2001 was used to examine variation in the relationship across 19 trial sites. Again, a negative association overall with both within and between variety associations was detected. However, there were also many cases where the association was not found. The association appears to be driven by both genetic and environmental factors; however, the association is not consistent enough to indicate a direct mechanistic link across all varieties. [ABSTRACT FROM AUTHOR]

The aerial spray program for the eradication of coca in Colombia uses Glyphos, a local formulation of glyphosate tank-mixed with an adjuvant product, Cosmo-Flux. There are some potential risks to amphibians from direct overspraying of shallow waters. In order to evaluate potential alternative mixtures, a field experiment was conducted at the Center of National Training of Police Operations in Tolima province, Colombia. Plants of coca were established with irrigation and grown to 75 cm tall. A randomized split-plot design experiment was laid out and sprayed with a range of glyphosate formulations and different adjuvants using an experimental ground sprayer. Assessments were made of plant vigor, height, and above-ground standing crop (fresh weight) 3 wk after application. Resprouting of plants was assessed at 9 wk after treatment. Unformulated glyphosate applied as the product Rodeo gave poorer control of coca than two formulated products, Roundup Biactive (from Europe) and Colombian Glyphos. In general, these products performed well without added adjuvants, giving control similar to that of the eradication mixture with Cosmo-Flux. There was some evidence that addition of the adjuvant Silwet L-77 and to a lesser extent Mixture B (from the United Kingdom) gave more rapid herbicide symptoms. There were also indications that glyphosate rates of less than 3.69 kg acid equivalents (a.e.)/ha could give control in the range of 95%. Depending on the environmental risk requirements, the experiment indicates that, should other spray mixtures be required, there are potential alternatives. These would require extensive field testing to cover different environmental conditions, different coca varieties, and particularly aerial application, prior to a recommendation. Should the glyphosate product require changing, Roundup Biactive may be considered. Should the adjuvant require changing, then on the basis of this research, Silwet L-77 and Mixture B would be good candidates for further evaluation. [ABSTRACT FROM AUTHOR]

Plant density can affect development and yield of bell pepper (Capsicum annuum L.). Information on the optimum plant density of different types of peppers in the Caspian Sea region is limited. The experiment was arranged in a randomized complete block with three plant densities (30,000, 42,000, and 78,000 plants·ha-1) with an in-row spacing of 0.45, 0.30, or 15 m between plants in rows 0.8 m apart and replicated three times. The 42,000 plants·ha-1 density produced suitable vegetative growth, best yield, and did not have any significant negative effects on bell pepper quality. [ABSTRACT FROM AUTHOR]

In mid-altitude of the North Eastern Hill (NEH) region of India, a second crop of rice following the harvest of main kharif (July to mid-November) rice is not possible due to early onset of low temperature (<15°C) from November onwards, which causes spikelet sterility in rice. A field experiment on double cropping of rice was conducted under mid-altitude subtropical wetland valley ecosystem of Meghalaya from 2004-05 to 2005-06 at Umiam (950 m amsl), Meghalaya. Out of the six varieties tested, IR-64 (43.2 q/ha), Aerobic rice IR 72176 (42.1 q/ha) and Krishna Hamsha (40.5 q/ha) performed well during pre-kharif season. Double cropping (main + ratoon) of IR-64 produced 75.4 q/ha of grain yield compared to 40.5 q/ha under improved monocropping of rice variety Sahsarang-1. Ratooning could save time (nursery and field preparation, transplanting, etc.), resources (labour, seeds, etc.) and gave higher productivity. The ratooning ability of Sahsarang- 1 (33.0 q/ha) and IR-64 (32.2 q/ha) was found to be highly promising. The sequence IR-64 in pre-kharif followed by its ratoon also gave 86 and 202% higher productivity over improved (40.5 q/ha) and local practice (25.0 q/ha) of monocropping respectively. It was found equally good with the best combination of IR-64 in pre-kharif followed by late kharif transplanted crop of Vivek Dhan-82 (system productivity of 80.4 q grain/ha). Duration of main crop varied from 135 to 158 days, whereas in case of ratoon it varied from 70 to 95 days. Therefore, it was concluded that ratooning has ample opportunity, especially in the NER region of India, where climatic conditions and non-availability of resources restrict the double cropping of rice by the farmers. The practice of double cropping would not only add to the national food basket, but would also increase the farmers' income and generate more employment in the region. [ABSTRACT FROM AUTHOR]

Abstract: A number of field studies have reported very high rice yields in Taoyuan, Yunnan province, China, and the physiological and ecological factors associated with high yield have been explored. However, little attention has been paid to differences in plant type. The main objective of this study was to reveal the plant type characteristics associated with the high rice yield through the comparison of two sites: Taoyuan, Yunnan province and Nanjing, Jiangsu province, China. The physiological and environmental factors were also discussed. Field experiments were conducted at two sites in 2006 and 2007. Three Indica F1 hybrid varieties, Eryou 107, Xieyou 107 and Eryouhang 1 in 2006, Eryou 107 and Xieyou 107 in 2007 were grown at two sites under optimum crop management to achieve maximum attainable yields. Leaf area, leaf length, leaf width, leaf angles, specific leaf weight (SLW) and specific leaf nitrogen (SLN) at heading, yield and yield components at maturity were determined. Daily radiation, air temperature and relative humidity (RH) were monitored. The highest yield of 18.5tha−1 was achieved by Eryou 107 at Taoyuan in 2006, and average yield of all varieties at Taoyuan was 96% and 85% higher than Nanjing in 2006 and 2007, respectively. The higher yield at Taoyuan was attributed primarily to the larger sink size, which was mainly caused by the greater number of panicles per m2. Biomass production was greater at Taoyuan than at Nanjing in 2006 and 2007, while differences in harvest index were very small. Compared with Nanjing, the rice planted in Taoyuan has greater leaf area index about 10 with smaller area per stem, shorter, wider and thicker leaves and smaller leaf angles. These results indicate that in addition to the higher biomass accumulation (main physiological factor) and the intense solar radiation with the large diurnal temperature range (main environmental factor), the greater leaf area index (LAI) with smaller area per stem, may be an important morphological factor contributing to the high yield in Taoyuan. [Copyright &y& Elsevier]

Abstract: Safflower (Carthamus tinctorius L.) growth and productivity are influenced by many factors like genotype, environment and agronomic practices. This field study was conducted to investigate the effects of phenotypic variation in physiological traits on development and yield of spring sown safflower under Mediterranean conditions. Twenty-one genotypes of varying origin were grown for two growing seasons without irrigation. Data were recorded on phenological development stages and seed yield, seed oil content, harvest index (HI) and, seed growth rate (SGR), biomass growth rate (BGR) and economic growth rate (EGR) were determined. Seed yield varied greatly among genotypes and ranged from 1333 to 2870kgha−1. There were large variations in SGR and EGR, which were linearly and positively related to seed yield and explained a large amount of the variation in yield, with r 2 values between 0.83 and 0.99. The relative contribution of biomass and HI to the variation in seed yield among genotypes appeared to be dependent on the growing season. When the environmental conditions allowed the genetically controlled variation in biomass production to become more apparent, most of the variation (87%) among genotypes in seed yield were due to the differences in biomass and were not resulted by genotypic differences in HI. Genotypes differed in seed oil content that ranged from 26.7% to 35.8%. Oil yield was mainly determined by seed yield in both seasons. Results indicated that spring sown safflower could be considered as an alternative rainfed crop in cool Mediterranean areas where winter kill is a problem. In conclusion, SGR, BGR and EGR were found to be important physiological determinants of seed yield, which could be used as additional selection criteria for yield improvement. [Copyright &y& Elsevier]

Abstract: Lack of water is a major limitation to crop production, particularly where roots of cereal crops are not able to access water stored in the subsoil. One way that roots penetrate the subsoil to access water is by following natural biopores – paths created by roots from previous crops, or as burrows from soil fauna. Burying a mesh layer horizontally in the soil can prevent root penetration to the subsoil. We used this technique with the novel modification that the mesh was punctured to create a defined number of holes per unit area; controlling access to the subsoil and to the water therein. The holes were of similar size to biopores. Five barley genotypes were late sown and grown during a dry summer. Monitoring of crop performance included plant height, leaf area and Normalized Difference Vegetation Index (NDVI). Crops grown with unrestricted access to the subsoil outperformed crops with limited or no access to the subsoil. Crops grown with controlled, limited access to the subsoil performed better than those with no access and the performance was generally related to amount of access. Changes in soil water content were in line with the amount of root access to the subsoil; confirming the association between subsoil water and crop growth and development in drought conditions. While there were no significant interactions between the genotypes and treatments used here, the method offers promise for studying some aspects of cereal ecophysiology and could be used to identify promising germplasm that may be of interest in plant breeding. Further testing is required to adapt the method for a wider range of crop types and soil conditions and testing for crops grown to maturity. [Copyright &y& Elsevier]

Abstract: Improving livelihood of resource poor farmers is an important goal of wheat research in developing countries. Although remarkable success has been achieved to date in developing widely adapted wheat cultivars, many resource poor farmers in marginal areas in developing world have not benefited. Participatory research could greatly enhance identifying cultivars according to the choice of the poor farmers. This study was conducted to examine how farmers’ selection criteria could assist breeders in identifying superior wheat cultivars, and determine if a new statistical analysis tool, GGE biplot, could be effectively used in selection of improved cultivar based on quantitative (grain yield) and qualitative data (farmers’ preference score). The field experiments were conducted in 3 years (2003–2005) in three mid-hill districts in the central Nepal involving resource poor wheat farmers. Sixteen wheat genotypes, including a long-term and a current commercial cultivar, were used in the study. Data were collected on agronomic traits considered important by the participating farmers. These included days to heading and maturity, plant height, effective tiller number, spike length, kernel per spike, 1000-kernel weight and grain yield. Farmers also qualitatively scored each genotype for multiple traits based on their preference. In general, the farmers used the same traits in selecting a superior cultivar that are used by breeders. However, relative importance of different traits differed, not necessarily following in line with the breeder preference. The cultivar superiority based on quantitative agronomic data (breeders’ criteria) and qualitative preference scores (farmers’ criteria) often showed synergies, however, there were differences as well. This indicates farmers’ ability to choose superior cultivars based on qualitative observation compared to tedious quantitative data recording in the on-station testing. In the first year, a greater number of farmers selected improved check as a better choice than recent advanced breeding lines. In the 2nd and 3rd years, the farmers preferred genotypes other than the checks. This underlines the importance of testing of advanced materials in farmers’ fields in multiple years. Principal component analysis using GGE-biplot was useful in identifying superior genotypes based on both quantitative and qualitative data recorded across environments. This approach could be useful in analyzing data from participatory agricultural research conducted under highly diverse farmers’ field conditions where it is easier to record observations on qualitative than quantitative scale. This technique can also be extended to on-farm participatory testing of other technologies. The findings bear implications for a broad range of participatory research and technology evaluation and verification. [Copyright &y& Elsevier]