bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Relationship Between Sugar‐Nitrogen Ratio and Reproductive Organs Abscission in Faba Bean (Vicia Faba L.)
Authors: Xia M. Z. 
Published: April 2008

AbstractThe changes of soluble sugar and total nitrogen content of vegetative organs in faba bean, sugar‐nitrogen ratio, abscission of reproductive organs and the relationship between sugar‐nitrogen ratio and abscission probability were studied using the faba bean cultivar Xichang Dabai. Plants were field grown in 1986, 1988 and 1990. The lands were separated into high yield land, middling yield land and low yield land according to grain yield at maturing stage. The soluble sugar content in vegetative organs (leaf + stem) was greatest from branching to floral initiation stages and pod‐set to filling grain stages, and distinctly decreased at the onset of bloom and maturing stages. The total N content was greatest at branching stage, and gradually decreased with growth. In general, the sugar and total N contents in high yield lands were greatest, followed by that in middling yield and low yield lands. The sugar‐nitrogen ratio varied depending on the soluble sugar content.Average yield on high yield lands, middling yield land and low yield land across 3 years were 5048.77 kg/ha, 3744.01 kg/ha and 2378.22 kg/ha, respectively. The total reproductive organs abscission exceeded 90 % of total flower buds. Abscission probability averaged across 3 yield lands and 3 years were 21.6 %, 84.0 % and 32.8 % in flower buds, flowers, and pods, respectively. Node 7–12 of canopy produced more flowers, and fewer flowers and pods were produced in the upper and lower regions. Photosynthate supply has been implicated in control of abscission. Faba bean reproductive organs abscission probability increased with the sugar‐nitrogen ratio of vegetative organs decreasing. It seemed that the soluble sugar content influenced significantly the shedding rate during flowering and pod‐growing stages.
Soil Temperature Simulation with Varying Residue Management
Authors: Brar G. S. , Unger P. W. 
Published: April 2008

AbstractMaintaining crop residue on the soil surface is an important part of conservation tillage. Although broad effects of residues on soil temperature (Ts) are well documented, the methods to predict soil temperatures under various surface residues and tillage conditions are limited. Using the Ts at 0‐, 0.05‐, 0.10‐, and 0.30‐m depths, we developed a simplified model to predict Ts for a uniform soil from air temperature (Ta) data. Data were collected under various tillage and surface residue conditions after wheat (Triticum aestivum L.) harvest. Residue management treatments were disk, sweep, and no‐tillage (with standing or shredded residues). The model predicts maximum and minimum Ts at 0‐, 0.05‐, 0.10‐, and 0.30‐m depths using maximum and minimum Ts measured at 2‐m above the soil surface, residue mass, apparent thermal diffusivity, and initial Ts profiles. Mean absolute deviation between simulated and measured maximum and minimum surface Ts were 0.53 and 0.44 °C or less, respectively. Root zone maximum and minimum T, were simulated within 0.14 to 0.91 and 0.27 to 0.95 °C, respectively, of the measured Ts. Greater precision of maximum and minimum soil temperature predictions with depth was obtained by using apparent thermal diffusivity calculated from initial Ts profiles. The proposed model can be useful in predicting Ts profiles required for crop growth modeling.
Changes in Leaf Water Relations and Injuries in Maize Seedlings Induced by Different Chilling Conditions
Authors: JANOWIAK F. , Markowski A. 
Published: April 2008

AbstractThe time course of injuries and electrolyte leakage as well as changes in leaf water content and relative turgidity during chilling at 5°C, 65 or 100 % relative humidity (RH) were determined for seedlings of two maize hybrids differing in chilling tolerance.In the course of chilling of entire seedlings the statistically significant injuries and increased leakage of electrolytes occurred first, followed by significant water deficit in leaves which was independent of RH and genotype. However, during prolonged chilling high and significant correlation between the level of chilling‐induced water stress and the extent of injuries was observed. Thus it has been assumed that the main factor responsible for primary chilling injuries in maize seedlings is the immediate influence of chilling temperatures on the cell membranes, and not the secondary water stress. The level of the water stress and the extent of the dehydration injuries under chilling conditions depended on the chilling sensitivity of the genotype. Differences between the examined genotypes consisted not only in delayed chilling injuries in a chilling tolerant hybrid, but also in significantly lesser effects of these injures on water relations.However, exposure to low temperature of the aboveground part or of the roots of the seedlings only, caused first the chilling‐induced marked water deficit in the leaves and next increased leakage of electrolytes. A direct effect of chilling temperature on the membranes in a situation when only a part of the seedling is being chilled, may be less harmful to the plant as a whole owing to normal functioning of the non‐chilled part.
Effect of Completion of Vernalization on Generative Development of Winter Rape (Brassica napus L. var. oleifera) Plants
Authors: Filek W. , Dubert F. 
Published: April 2008

AbstractGerminating seeds and young plants of winter rape var. Górczañski were vernalized for 56–63 days under conditions of 9‐hour day, at the temperature 2 and 5 °C and in continuous darkness at the temperature 2 °C. After vernalization the plants grew under conditions enabling to complete vernalization: in a glass‐house at the temperature day/night 15/10 °C and in semi natural conditions of open vegetation hall in the period from June till August. After sub‐optimal vernalization further growth of the plants at lowered temperature increased its effectiveness (completion of vernalization). Depending on the degree of the vernalization of the plants the completion of their vernalization was both obligatory, i.e. conditioning the acquisition of the ability of generative development, and facultative i.e. accelerating this development. It has been demonstrated that the population of plants of the examined variety is strongly differentiated not only with respect of vernalization requirements in the particular plants, but also what regards the effectiveness of vernalization completion. New observations have been made indicating that the mechanisms controlling the successive phases of generative development, i.e. phase of forming flower buds and the flowering phase are not identical which may be interpreted as indicating that the “flowering factor” is polymorphous.
Growth, Yield and Nodule Activity of Phaseolus vulgaris L. as Affected by Soil Moisture
Authors: Sangakkara U. R. 
Published: April 2008

AbstractA study evaluated the response of two varieties of beans (Phaseolus vulgaris L.) to different soil moisture levels during a dry season. The soil moisture regimes maintained throughout the growth period were field capacity, 70–75 %, 50–55 % or 20–25 % available soil moisture.Plant growth, yield and nodulation were optimal when plants grew at high soil moisture levels. With increasing stress, all measured parameters of both varieties were reduced. However, polebeans, with its vine type of growth was affected to a greater degree than bushbeans. In contrast, nodulation and nodule activity of both variables was affected by moisture stress.A second experiment evaluated the effects of different soil moisture levels over the growth cycle of bushbeans, which produce greater yields under drier conditions. The highest yields were obtained at higher moisture levels throughout the growth cycle. Moisture stress up to flowering reduced yields to a greater extent than when the plants were subjected to reduced soil moisture after flowering appearance. Some casual mechanisms of the results of the experiments and possible implications for incorporating this popular vegetable legume in rainfed agricultural systems are presented.
Nitrogen Fertilizer and Protein, Lipid, and Non‐structural Carbohydrate Concentrations During the Course of Maize Kernel Filling
Authors: Zhang Feng , Mackenzie A. F. , Smith D. L. 
Published: April 2008

AbstractA field experiment was carried out at four location‐years in Southwestern Quebec, Canada in 1990 and 1991, to evaluate the effects of nitrogen (N) application on protein, lipid, non‐structural carbohydrate (NSC), and remaining grain components concentrations of maize (Zea mays L.) grain during kernel development. Three N fertilizers (ammonium nitrate, urea, and calcium ammonium nitrate) were compared for plants receiving pre‐plant incorporated N fertilizer at 180 kg ha‐1 as well as a control which received no N fertilizer. The results indicated that between 20 and 30 days after pollination (DAP) protein concentration of maize kernels declined sharply, thereafter only slightly, irrespective of the treatment. At most stages and in all four location‐years protein concentration was raised significantly by N‐application without clear difference between N‐fertilizer sources. At 20 DAP seeds of N‐fertilized plants contain 25.5 mg g‐1 more than those without N‐application (control); later on, this difference was lower (12.8 mg g‐1) but remained constant over time if averaged over N‐sources and location‐years. At most growth stages and in most location‐years the lipid concentration did not respond to N fertilizer application. Lipid concentration followed an “N” shaped curve over the course of grain development. Non‐structural carbohydrate (NSC) concentration increased significantly during grain filling and showed little effect due to N application. However, at most growth stages in the four location‐years, the concentration of remaining grain components tended to decline with N application. A significant negative correlation existed between the changes in protein concentration and NSC concentration during kernel development.
Some Effects of Soil Salinity on Growth, Development and Yield of Rapeseed (Brassica napus L.)
Authors: Boem F. H. Gutierrez , Scheiner J. D. , Lavado R. S. 
Published: April 2008

AbstractThe effects of increasing soil‐salt levels on emergence, shoot and root growth and yield composition of rapeseed were investigated. A range of electrical conductivity (EC) values in the soil solution from 2.3 dS m‐1 to 10.3 dS m‐1 was obtained by adding NaCl to the substrate. The emergence was significantly (P < 0.05) decreased at EC values higher than 6 dS m‐1 Above this value, a delay in the appearance of leaves and of the first visible internode was observed. The further increase of salinity level extended the period for siliqua formation and grain filling, and plant height, pod number and grain number per plant were lowered. However, the cultivar used showed the ability of counterbalancing for this lower grain number by increasing the seed weight, thus there were no variations on seed yield. The seed oil and protein content were also not affected by the changes in salinity. Root growth was adversely affected when salinity levels exceeded 6 dS m‐1. Beyond this value, short tuber‐like roots became remarkably frequent. This may be an adaptation mechanism of this species to saline stress; a similar reaction in rapeseed is known in adaptation to drought stress.
Nitrogen, Phosphorus and Potassium Concentrations in Developing Maize Grains
Authors: Alfoldi Z. , Pinter L. , Feil B. 
Published: April 2008

AbstractA 2‐year (1989, 1990) experiment was conducted in the Carpathian Basin near Keszthely, Hungary to evaluate the course of nitrogen (N), phosphorus (P) and potassium (K) concentrations in the developing grain. Two maize hybrids were grown at four rates of N application (0, 50, 150 and 250 kg N ha‐1). Plots had been fertilized at these levels since 1983. As a result of the long‐term N treatments, stocks of P and K in the soil decreased as the rate of N application increased. As expected, concentrations of N in the mature grains were higher at high doses of N, whereas the rate of N application had little impact on the P and K concentrations in the ripe grains. Only in 1989, when grain yield showed a relatively stronger response to applications of N than in 1990, were the concentrations of P and, to a lesser extent, K reduced by additions of N. These results illustrate that P and K concentrations in the grain are well‐buffered against increments in grain yield resulting from the application of N and are also relatively insensitive to low supplies of P and K in the soil. In both hybrids, concentrations of N, P and especially K declined considerably with ongoing grain filling, irrespective of N treatment. Differences in concentrations of P and K for hybrids existed but were not consistent across years.
Lodging and Yield of Dry Peas (Pisum sativum L.) as Influenced by Various Mixing Ratios of a Conventional and a Semi‐Leafless Cultivar
Authors: Schouls J. , Langelaan J. G. 
Published: April 2008

AbstractLodging is a serious problem in dry pea production in North‐West Europe. Therefore, lodging and its effects on yields were studied in five field‐experiments with two cultivars with two different canopy structures, both as single crop and in various mixing weight ratios. In 1985, mechanically simulated lodging decreased yield by about 45% in both the conventional type cv. Rondo and the semi‐leafless type cv. Solara, by reducing both the number of seeds and seed weight. Natural lodging brought about the same effect in ‘Rondo’ but in ‘Solara’, however, effects were less because of delayed lodging. In 1986, 1987 and 1988, mixtures of the conventional cv. Finale and Solara showed delayed lodging compared to ‘Finale’ single and tended to produce higher yields than the single crops of both cultivars. Polynomial analysis of the yields of all mixing experiments showed maximum yields at 53%‘Solara’ (quadratic analysis) or 67%‘Solara’ (cubic analysis). Thus, mixing high yielding, lodging sensitive conventional cultivars with lower yielding but lodging resistant semi‐leafless cultivars may improve yield in dry peas.
Crop Response to Improved Drainage of Vertisols in the Ethiopian Highlands
Authors: Abebe M. , Mamo T. , Duffera M. , Kidanu S. Y. 
Published: April 2008

AbstractThe effect of flat seedbed, traditional ridge and furrow and improved drainage of broad bed and furrow (BBF) on grain and straw yield of durum wheat, chickpea and lentil at several Vertisol sites between 1988—1991 was such that on three crops the BBF system gave the highest grain and straw yields at all locations and seasons. This was followed by traditional ridge and furrow system and the least yield was obtained from flat seed beds. The extent of drainage influence on yield was dependent on rainfall quantity, location (clay content) and crop species. The advantages of the BBF technology in improving drainage and increasing crop yield are discussed in their contexts of better cropping systems.
Foliar Nutrient Analyses in Bananas Grown in the Highlands of East Africa
Authors: Wortmann C. S. , Bosch C. H. , Mukandala L. 
Published: April 2008

AbstractData gathered from 45 farms in the Kagera Region of Tanzania were used to estimate critical nutrient levels (CNL) of foliar tissue and norms of the Diagnosis and Recommendation Integrated System (DRIS) for bananas (Musa spp.) grown in the highlands of East Africa.CNL values are proposed as 3.1 % N, 1.13 % Ca, 0.48 % Mg, 18.4 ppm Zn and 10.0 ppm B. Optimum ranges for cation ratios were estimated as 0.54—0.67 for K/(K + Ca + Mg), 0.22—0.32 for Ca/(K + Ca + Mg) and 0.09—0.15 for Mg/(K + Ca + Mg). Productivity of bananas and foliar levels of P, K, S, Fe, Mn and Cu were too weakly related to estimate CNLs for these nutrients. A set of DRIS norms for East African Highland bananas is presented.
Performance of Sugarcane (Saccharum officinarum L.) Under Surface Drip, Sub Surface Drip (Biwall) and Furrow Methods of Irrigation
Authors: RAMESH P. , KAILASAM C. , SRINIVASAN T. R. 
Published: April 2008

AbstractField experiments were conducted at the Sugarcane Breeding Institute, Coimbatore, India during 1989–93 to study the productivity and water use efficiency of sugarcane under different methods of irrigation. The results showed that there could be a 44 % saving in water with higher water use efficiency in drip irrigation compared to conventional furrow irrigation. Among drip irrigation systems in the plant crop, sub surface drip (Biwall) at 40/140 cm spacing recorded a significantly higher number of millable canes, cane length and single cane weight compared to either conventional furrow irrigation or furrow irrigation based on IW/CPE (Irrigation Water Cumulative Pan Evaporation) ratio. In ratoon crop, Biwall irrigation at 60/120 cm gave significantly higher cane length and single cane weight compared to any other methods of irrigation. However, cane and sugar yields in Biwall irrigations were on par with conventional furrow irrigation but superior to either surface drip or furrow irrigation based in IW/CPE ratio.
The Influence of Johnsongrass Infestation and Nitrogen Rates on Grain Sorghum
Authors: Kegode G. O. , Bishnoi U. R. , Mays D. A. 
Published: April 2008

AbstractGram sorghum [Sorghum bicolor (L.) Moench] is grown on marginal land and johnsongrass [Sorghum haiepense (L.) Pers] is the most common and hard to control weed in this crop. The agronomic performance of gram sorghum at different nitrogen (N) and johnsongrass infestation levels in the field has not been adequately investigated. Therefore, research was conducted on a Decatur silty clay loam soil (Rhodic Paleudult) to determine the influence of N rates (0, 40, 80 and 120 kg ha‐1) and johnsongrass infestation levels (0, 2, 4, 6 and 8 plants per 5 m crop row) on the growth and yield of grain sorghum (cv. GK522G) and johnsongrass. Increase in N rates increased seed weight, seed yield and percent protein in grain sorghum as well as dry matter and percent protein of johnsongrass. The increase in johnsongrass infestation (from 0 to 8 plants per 5 m crop row) significantly decreased the performance of grain sorghum and johnsongrass at all the N rates. The results suggest that 40 kg N ha‐1 with up to 2 johnsongrass plants per 5 m crop row or 80 kg N ha‐1 with up to 4 johnsongrass plants per 5 m crop row produced grain sorghum yields equivalent to absence of johnsongrass in the crop.
Stickstoffaufnahme und Stickstoffrückstände von Hauptfrucht‐und Ausfallrapsbeständen
Authors: Aufhammer W. , Kubler E. , Bury M. 
Published: April 2008

AbstractNitrogen Uptake and Nitrogen Residuals of Winter Oil‐Seed Rape and Fallout RapeThe objective of the investigation was a study of the relationship between seed dry‐matter production and vegetative dry‐matter production in oil‐seed rape crops and their dependence on the production conditions. In addition to the relationship between the N‐uptake during the vegetation period and the N‐residue after harvest was of major interest. Furthermore the potential for N‐uptake in fallout rape was measured. Over two vegetation periods factorial field experiments with winter oil‐seed rape, cv. Lirabon, different drilling techniques and different nitrogen fertilization levels were tested. Measured traits were: the dry‐matter accumulation including root mass and fall‐off leaf‐material mass, the N‐uptake of both the oil‐seed crops and the fallout rape stands, and, simultaneously, the soil NO3‐N content. Finally the harvest indices and the N‐harvest indices were calculated.Combined with a N‐uptake of up to 330 kg N/ha, oil‐seed rape crops produced up to 200 dt dry matter/ ha. At seed yield levels of 33dt/ha (d.m.), harvest indices varied from 0.14—0.23 and N‐harvest indices varied from 0.30–0.50. As a result of the residue of vegetative plant material at harvest, leaf losses before harvest and the soil NO3‐N‐contents at harvest up to 275 kg N/ha remained in the field. After the harvest of oil‐seed rape, the soil NO3‐N‐contents were quickly reduced by emerging and growing fallout rape stands. However, following soil‐preparation measures in the autumn, a continuous rise in the soil NO3‐N‐content was observed.
Productivity of Maize (Zea mays L.) in Relation to Morphological and Physiological Characteristics under Varying Amounts of Nitrogen Supply
Authors: Greef J. M. 
Published: April 2008

AbstractIn a field trial located in a northern region of Germany, characterized by a Podzol soil and increasing N fertilization resulted in an enhanced N uptake of the maize (Zea mays L.) variety “Felix” with increasing N fertilization ranging from 0 kg N ha‐1 (N1) to 60 kg N ha‐1 (N2) and to 160 kg N ha‐1 (N3). The growth conditions reached only nearly optimal temperature for biomass allocation in a short period of July and August 1990. The plant productivity was stimulated due to higher N uptake and N utilization to values of nearly 1600 g ha‐1. The N efficiency decreased with increasing N fertilization.A greenhouse experiment was conducted to study the effects of varied nitrogen nutrition on the development of maize plants under standardized growth conditions, comparable to the sub optimal growth conditions of the field experiment. Physiological and anatomical parameters were measured. Within a range of 0.2—1.0 mg N cm‐2 of leaf nitrogen, the chlorophyll concentration and the CO2 exchange rate showed a linear relationship with the reduced N in the leaf. Above 1.0 mg N cm‐2 no further increases in chlorophyll levels or photosynthesis were observed. Nitrate reductase activity was stimulated throughout the N range supplied. The activities of photosynthetic enzymes (PEP carboxylase, Nadp malic enzyme, RubP carboxylase) was increased from the low (0.19 g N kg‐1 soil) to the middle N level (0.37 g N kg‐1 soil). Under conditions of a high N supply (0.75 g N kg‐1 soil) the activity decreased, except Nadp malic enzyme. This effect was accompanied by alterations of the internal structure of the leaf. Leaf thickness and size of the mesophyll parenchyma were less at the medium nitrate supply. Other anatomical parameters were influenced in proportion to leaf nitrogen status. Stomatal index was not affected by N supply, but lengths and widths of epidermal and stomatal cells as well as the distance between stomata and vascular bundles were increased by high N supply. It is proposed that above an optimal range of leaf nitrogen, maize plants cannot use the potential advantage of the C4 mechanism and the N utilization shows maximum efficiency in the intermediate N level under the sub optimal growth conditions used in the greenhouse experiment.
Effect of Weed Removal on Productivity of Chickpea (Cicer arietinum L.) and Lentil (Lens culinaris Med.) in a Mediterranean Environment
Authors: AL‐Thahabi S. A. , Yasin J. Z. , ABU‐Irmaileh B. E. , Haddad N. I. , Saxena M. C. 
Published: April 2008

AbstractThree field experiments were conducted on chickpea (Cicer arietinum L.) and four on lentil (Lens culinaris Med.) at different winter‐sown rainfed locations in Jordan from 1988/89 to 1990/91 to study the effect of the duration of weed‐free and weed‐infested conditions on yields and yield components of the crops. Chickpea seed yields were reduced on average by 81 % and straw yields by 63 % when fields remained weed infested until harvest compared with weed‐free conditions throughout the growing season. The corresponding lentil seed and straw yield decreases were 63 % and 55 %. As the duration of weed‐free period increased and the duration of weed‐infested period decreased, yields increased. However, the critical period of weed interference was between 35 and 49 days after emergence in chickpea and between 49 and 56 days after emergence in lentil, when these crops were at an advanced stage of vegetative growth. There were significant negative correlations between the weed dry weight and the seed or straw yields. The reduction in seed yields in both crops because of weed interference occurred mainly through the reduced number of pods /plant, which in turn was partly the result of reduced number of secondary branches. In chickpea, some reduction also occurred through reduced 100‐seed weight.