bluuebunny/crossref_metadata_2025 huggingface dataset:
Irrigation Scheduling and Watermelon Yield Model for the Jordan Valley
Authors: Battikhi A. M. , Hill R. W.
Published: April 2008

A crop yield and soil water management simulation model (CRPSM) developed at Utah State University was modified, calibrated and tested using local weather data and field results from a trickle irrigation experiment with different mulching on watermelon (Citrullus lanatus), carried out at the University of Jordan Research Station, in the Jordan Valley.

Simulated irrigation schedules were then applied with some of the four options provided by the model. The water yield index, WYI, introduced by Battikhi and Hill (1985) to select the most efficient schedule as based on yield and water use efficiency, was then determined. WYI ranged from 27 to 87. The field schedule, WM2, had a WYI of 62. Whereas, the model provided a much better schedule, WM7 (WYI = 86). WM7 requires 17 irrigations of 2.0 cm per irrigation totaling a water supply of 44.1 cm with an irrigation season starting on April 7 to give a yield equivalent to the potential yield, 80.0 MT/ha. On the other hand, the best field schedule, WM2 under transparent mulch, required 14 irrigations to provide 45.9 cm (including rainfall and soil moisture change), with a season starting on April 28 resulted in a yield of 68.8 MT/ha. So we can see that by using the same amounts of total water supply but with different schedule we can get the potential yield. The model has, therefore, provided few better schedules that can be tested in the field at lower costs before final recommendations are made.
Untersuchungen zur Leitbündelstruktur der Ackerbohne (Vicia faba L.)
Authors: Hoppe J. , Pommer G.
Published: April 2008

Investigations on the vessel structures of broad beans (Vicia faba L.)

The number of vessels was observed in the fruit bearing axes of some varieties from Vicia faba Minor, Equina and Major during flowering. These investigations were also made on some F2‐ progenies of crosses from minor×equina and Paucijuga×Eufaba and on some topflower plants.

The varieties of Minor and Equina had about 12 vessels on the base of the axis, these diminished to the top of the axis 3 or 4 vessels just before the last flower. The varieties of Major had 12 vessels on the base of the axis too, but these diminished faster because of the smaller number of flowers on the axis. In Paucijuga the number of vessels on the base of the axis was only 3 to 4. Plants of Paucijuga had only 2 or 3 flowers per axis.

Progenies from crosses between Minor×Equina had more vessels on the base of the axis, probably due to a heterotical inheritance. In progenies from crosses between Paucijuga×Eufaba an intermediate inheritance was found in the number of flowers per axis and in the number of vessels.

Due to the investigations on a comprehensive material it is probable that the described vessel structure exists in most broad beans. This structure is complex arranged and modifyable. With this organization it is quite unprobable that the vessel structure will be a yield reducing factor.
The Effect of Different Soybean Tillage Systems on Infiltrability and Erosion Susceptibility of an Oxisol in Paraná, Brazil
Authors: Roth C. H. , Meyer B. , Frede H.‐G. , Derpsch R.
Published: April 2008

Measurements of infiltrability were carried out during the soybean vegetation period in three different tillage systems on an Oxisol, with the aim of estimating relative erosion susceptibility. The tillage systems studied were conventional tillage (disc plow), minimum tillage (chisel plow) and no‐tillage. Infiltration was determined as the difference between rainfall applied with a portable rainfall simulator and runoff collected from mini‐plots.

During all growth stages of the soybeans, infiltrability under no‐tillage was higher than under conventional tillage. Minimum tillage took an intermediate position. Lowest overall infiltrability and consequently, highest relative erosion susceptibility was observed in the early growth stage after planting, in a wet year, when the degree of soil cover was also lowest. Infiltrability was mainly affected by degree of surface seal development as a result of natural rainfall energy the soil surface had received prior to measurements, as well as degree of soil cover. Highly significant correlations were found between the calculated sum of erosivity indices one month before measurement and the total infiltration. Differences in bulk density and macroporosity had hardly any effect on infiltrability.

The better performance of no‐tillage in controlling erosion observed in Brazil can thus be explained by the higher degree of soil cover in comparison to the other tillage systems studied.
The Effect of Air Temperature on Growth and Alkaloidal Yield of Hyoscyamus muticus L.
Authors: Reda F. , Raafat A. , Abdel‐Halim M. A. , El‐Kadi M. , Yacob Z.
Published: April 2008

The effect of natural air temperature on the vegetative growth and alkaloidal yield of H. muticus L. was studied. The highest number of branches, diameter, fresh and dry weights of stem and roots occurred in September sowing at full‐flowering and fruiting stages. Relatively higher temperature in Sept. sowing favoured leaf growth (number, area and dry weight). Hyoscyamine yield in different organs of the plants sown in Sept., excessively exceeded all other sowings during flower budding and full‐flowering stages. Hyoscine yield was quantitatively very small as compared with that of hyoscyamine and even could not be detected in the leaves of winter sowings during full‐flowering stage.
Effect of Seeding Date on the Growth of Sod‐seeded Lucerne
Authors: Kunelius H. T. , Campbell A. J.
Published: April 2008

Lucerne (Medicago sativa L.) is a valuable forage legume but it is short lived in many regions and periodic reseeding is necessary to maintain adequate lucerne in swards. Sod‐seeding is a fast, one pass method of renovation but variable seedling establishment of sod‐seeded lucerne has been experienced in the Atlantic Region of Canada. Experiments were conducted in two consecutive years to determine seeding date effects on establishment and growth of sod‐seeded lucerne in timothy (Phleum pratense L.) dominant swards at two sites. In the first experiment lucerne was sod‐seeded on four dates in swards, band sprayed with paraquat at 0.5 kg/ha−1, and was compared with sod‐seeded red clover (Trifolium pratense L.). In the second experiment the effects of four sod‐seeding dates of lucerne and broadcast or band spraying of paraquat in swards were determined. Sod‐seeding lucerne between late April and mid‐June resulted in the best establishment and yields. Yields of sod‐seeded lucerne were usually greater with broadcast than with band applied paraquat. Red clover established more readily and made a greater contribution to total yields than lucerne.
Reaktion verschiederer Mais‐Inzuchtlinien und ‐Hybriden auf steigendes Stickstoffangebot
Authors: ÜLger A. C. , Becker H. C. , Kahnt G.
Published: April 2008

Response of maize inbred lines and hybrids to increasing rates of nitrogen fertilizer

The response of 8 flint and 8 dent inbred lines and 16 flint × dent single crosses to three rates of nitrogen fertilizer (80, 160, 240 kg/ha) were tested in the years 1983 and 1984 in field trials at one location. The material represents a broad range of maize genotypes not strongly selected for kernel yield.

The mean kernel yield of all hybrids increased from the lowest to the medium N treatment by 7.6 % in 1983 and by 4.9 % in 1984. The highest fertilizer level resulted in an additional yield advantage in the two years of 6.1 % and 4.4 % respectively. An increased nitrogen rate had a positive effect on plant height, leaf area index, grains/cob, 1000 kernel weight, and protein content. Lodging resistance and dry matter content were not significantly influenced by N treatments. A significant interaction between genotype and N treatment was observed for leaf area index, 1000 kernel weight, and protein content, but not for kernel yield. The correlations of kernel yield with other traits investigated were not consistent over years and nitrogen treatments.
Factors Associated with Reduced Yields of Delayed Plantings of Soybean1
Authors: Egli D. B. , Guffy R. D. , Heitholt J. J.
Published: April 2008

Field experiments were conducted for four years (1981 to 1984) at Lexington, KY, USA (38° N latitude) to determine the causes of reduced yields associated with delayed plantings of soybean (Glycine max [L.] Merrill). Five cultivars were planted in mid‐May and early July in row spacings ranging from 18 to 89 cm and the plots were irrigated to minimize moisture stress. Yields were significantly reduced by delayed planting because of reductions in the number of seed m−2 and mass seed−1. The yield reduction under irrigation indicates that moisture stress is not a major cause of reduced yields from delayed plantings. The reductions in seed number were associated with lower insolation interception during flowering and pod set and with smaller vegetative mass (g m−2) at growth stage R5 (beginning seed fill). The data suggest that a vegetative mass at R5 greater than that required to intercept 90 % or more of incident insolation is required to maximize seed number. The length of the seed filling period was not affected by planting date. Mass seed−1 was positively related to mean air temperature during seed filling, which suggests that the smaller seed from delayed plantings are a result of the lower temperatures associated with the later maturity.
Effects of High Soil Temperature and Water Stresses on Malian Pearl Millet and Sorghum during Seedling Stage
Authors: O'Neill M. K. , Diaby M.
Published: April 2008

Pearl millet (Pennisetum americanum [L.] Leeke) and sorghum (Sorghum bicolor [L.] Moench) can suffer from poor stand establishment under conditions of high soil temperature and water stresses. A line source sprinkler irrigation system and a charcoal pit technique were used to evaluate stand establishment and high correlations existed between the two methods. It may be possible to use the charcoal pit technique as a predictive tool in drought resistance breeding programs.
Effect of NH4+ Nitrogen on Phosphorus Uptake by Canola, Lentils, Soybeans and Wheat
Authors: Sangakkara U. R. , Cho C. M.
Published: April 2008

Phosphorus and ammonium nitrogen placed together has been shown to increase P uptake by crops, especially cereals, Thus, the objective of this study was to compare this effect on four crops grown in Manitoba. Plants harvested at flowering indicated greater P uptake in lentils, soybean and wheat, when P and NH4+‐N were placed on the same band. In contrast, canola did not respond to this treatment. Possible relationships of these ions are presented.
Modelling the Vertical Variability of the Radiation Flux Density in a Closed Green Crop Stand
Authors: Prasad S.
Published: April 2008

As the incident radiation penetrates vertically in any plant stand having green closed canopy, the PAR flux density (Rn) gradually decreases with depth in a manner that the radiation flux density (Rn) is inversely proportional to the photosynthetic‐area percentage (Pap), and the radiation interception density (Rid). The radiation interception density (Rid) is a function of net radiation intercepted, total photosynthetic‐area percentage and the thickness of that photosynthetic‐area.
The Effect of Soil Conditioners on Water Movement through Lateritic Sandy Loam Soil
Authors: Sen K. K. , Bhadoria P. B. S.
Published: April 2008

The lateritic sandy loam soil of Gopali suffers by a high infiltration rate and percolation loss. The investigated soil was treated by four soil conditioners, CMC, PVA. Guargum and Lignosulphonate (LIG.) at 0.05 per cent and 0.10 per cent concentration level. The infiltration of water at −2 m bar pressure in horizontal column of soil was studied. The experimental results indicate that the lignosulphonate has increased the time by 30% and 70% to penetrate the 15 cm depth of soil column at 0.05 and 0.10 per cent concentration level, respectively. In the case of PVA, increase of time was 18 per cent and 33 percent at these the concentration level. Guargum at high concentration level increased the time by 31 per cent to penetrate the same depth of soil. Whereas CMC at high concentration reduced the time by 8 per cent. Similar trends were found in case of volume of water penetration and infiltration rate of treated soil.
Einfluß der N‐Düngung auf Ertragsentwicklung landwirtschaftlicher Kulturen und Veränderung des mineralischen N‐Gehaltes im Boden bei achtjährigen Dauerversuchen
Authors: Knittel H. , Zerulla W.
Published: April 2008

Influence of long‐time Nitrogen‐fertilizing on yield response of agricultural crops and mineralized Nitrogen in soil

In the years 1979–1986 a fertilizer trial with increasing Nitrogen amount was performed in order to prove the Nmin‐method according to Scharpf and Wehrmann. The Nmin‐method regards the mineralized N in soil (Nmin) for optimizing the N‐fertilizer amount at the begin of vegetation, could be confirmed. The optimal N‐rate (including Nmin) was for winter wheat and winter barley 120 kg/ha, winter rye 100 kg/ha and sugar beet 200 kg/ha. For cereals additional N‐rates were given at the end of tillering 20 kg/ha N and at ear emergency 60 kg/ha N. For the optimal N‐fertilizing system we found a positive N‐balance (input‐output) in a range of 10–25 kg/ha. The influence of N‐fertilizing on the mineralized N‐amount in soil was very small comparing to influence of weather, soil type or crops. Only at one location a little increase of Nmin (10–15 kg/ha) could be observed after a positive N‐balance (50 kg/ha).
Relationship of Root and Shoot Characters in Parent, F1 and F2 Populations of Rice
Authors: Sasmal B.
Published: April 2008

The direct and indirect contributions of root characters — root length, roots/plant, fresh and dry root weight on grain yield/plant were worked out from a 7 × 7 diallel set of rice hybrids. The materials were grown in pots with four replications. Path analysis was done at genotypic level of correlation.

The grain yield/plant showed positive correlation with all the root characters in parent, F1 and F2 except with roots/plant in F1 population. Fresh root weight demonstrated positive direct effect on grain yield/plant in all the three generations. Roots/plant had highly positive direct effect in F2. Direct effects were negative in respect of root length and dry root weight in F2 generation.
Leaf Growth, Reproduction Growth and Yield in Cotton (Gossypium hirsutum L.)
Authors: Bhatt J. G.
Published: April 2008

In three genotypes of cotton differing in height, reproductive growth increased with the increase in number and size of the leaves and was maximum when leaf area was also maximum. After this stage though the leaf area continued to remain high for 3 weeks and then declined, more buds were shed than produced. Within genotypes the taller type LRA 5166 produced more leaves with greater area than MCU‐5 whereas the dwarf type KD (CAKD) had more leaves with lesser area than MCU‐5. The maximum leaf area as well as the yield of seed cotton were one and a half times in LRA 5166 than in MCU‐5. Though the maximum leaf area in MCU‐5 was also one and a half times than in KD (CAKD), their seed cotton yields were the same. Since even during the period of maximum reproductive growth substantially more number of leaves were produced by LRA 5166 and KD (CAKD) than MCU‐5, maintenance and retention of bolls appeared to depend not only on leaf number and area but on their photosynthetic efficiency and perhaps nutrient reserves.
Electrophoretic and Serological Studies of the Seed Proteins of some Members of the Subfamily Papilionoideae
Authors: Sammour R. H.
Published: April 2008

Electrophoretic and Immunochemical relationships amongst storage proteins of some tribes of subfamily Papilionoideae have been investigated on the basis of their legumins and vicilins subunit compositions. SDS‐PAGE, immunodiffusion, and “Western” blotting technique are the technique which were used in this study. Electrophoretically, it has been found that each tribe has a distinctive electrophoretic pattern. Immunochemically, legumin and vicilin‐like proteins were detected for the first time in some members of Phasealeoe, Glycineae, Cajaneae, and Diocleae.
Optimale Stickstoffdüngung aus ökonomischer Sicht in Abhängigkeit von Standort, Vorfrucht, Bodenbearbeitung, Phosphat‐ und Kalidüngung sowie Sortenwahl
Authors: Kling A.
Published: April 2008

Economically optimal N‐fertilization as influenced by location, preceding crop, cultivation of soil, phosphatic and potassic fertilization and choice of variety.

– The economically optimal quantity of N‐fertilization is mainly influenced by location, preceding crop, cultivation of soil, phosphatic and potassic fertilization and choice of variety. The optimal organization of these factors, however, to the extent that it can be influenced by the farmer, is a precondition of an effective N‐fertilization.

– Depending on the above‐mentioned factors the economically optimal quantity of N‐fertilization shows a great variation. In the majority of cases the optimal N‐quantity to winter wheat ranges between 100 and 180 kg/ha and to sugar beets between 120 and 200 kg/ha.
Soil Aggregates and Growth of Wheat
Authors: Agrawal R. P. , Jhorar B. S.
Published: April 2008

The effects of different soil aggregate sizes (10–4, 4–2 and < 2 mm) in the seed‐root zone were investigated on the growth of wheat in a sandy loam soil (Typic Ustochrepts, fine loamy) under controlled ecological conditions. Plant growth, as evaluated by the plant height, length of main root, dry matter and root weight, was greater in 10–4 mm soil aggregate treatment than 4–2 mm soil aggregate treatment, which in turn was greater than < 2 mm soil aggregate treatment. The coarser tilth of the seed‐root bed maintained higher apparent growth rates, studied upto 84 days after sowing and this declined with decrease in aggregate sizes.
Agronomic Performance of Wheat (Triticum aestivum L.) as Influenced by Moisture Stress at Various Growth Stages and Seeding Rate
Authors: Hassan U. A. , Ogunlela V. B. , Sinha T. D.
Published: April 2008

A field experiment was conducted at Samaru, Nigeria during the 1981–82 dry season to determine the yield and growth responses of wheat (Triticum aestivum L.) to moisture stress imposed at various growth stages and to seeding rate. It was also to identify wheat growth stages that are most sensitive to soil moisture stress. Treatments tested include three seeding rates, namely, 75, 100 and 150 kg per ha, and seven drought treatments, effected by missing one or two consecutive irrigations at different growth stages.

Withholding irrigation at any growth stage prior to anthesis had detrimental effects on most of the growth characters and stress during crown root initiation (CRI) and jointing reduced most of the yield characters. Missing two consecutive irrigations at any given growth stage reduced grain yield more than did missing one irrigation; the greatest reductions in grain yield were 13 and 65% when one irrigation was missed at CRI and two consecutive irrigations were missed at jointing (the most sensitive growth stage) respectively. Moisture stress was also detrimental to number of grains, spike number, spike length, leaf area and number of tillers. A seeding rate of 100 kg per ha produced the best wheat performance in the present study.
Direct and Residual Effect of Slow Release Urea Fertilizers in Rice‐Wheat Cropping System
Authors: Kolhe S. S. , Mittra B. N.
Published: April 2008

Field experiments were conducted for three consecutive years during 1979—80 to 1981—82 to find out the relative efficiency of different forms of urea fertilizer for rice and their residual effect on the succeeding crop of wheat. In rice crop, root zone placement of nitrogen as urea super granule 1.0 g size (USG) under puddled field condition was proved to be superior to other sources. The relative efficiency of USG, urea in splits and sulphur coated urea (SCU) was 116.92%, 107.71% and 101.41% respectively as compared to ordinary urea at planting. Significant residual effect on succeeding crop of wheat was recorded in case of SCU which was followed by USG, urea in splits and urea at planting.
Effect of Soil and Foliar Fertilization on Inoculated and Uninoculated Soybeans
Authors: Kamel M. S. , Metwally A. A. , Abdalla S. T.
Published: April 2008

Two experiments of soil N‐fertilization and Rhizobium inoculation were conducted in 1981 and 1982 at Giza, Egypt. Soybean was sprayed with a commercial micronutrients mixture, and with urea.

In the first experiment, soil N‐fertilization 0, 142.8 and 214.2 kg N/hectare were applied to uninoculated plants, whereas, in the second one, local inoculum was used alone or along with addition of a starter dose of N (47.6 kg N/hectare).

Urea applications were at pod filling period (R4, R5 and R6 stages), whereas, micronutrients mixture was applied at 25 days from planting.

Plant dry weight, leaf area/plant, plant height, pod and seed number/plant, seed weight/plant, seed yield and crude seed protein content increased significantly with nitrogen application to uninoculated soybean plants; whereas the starter dose of N had no significant effect on any of these traits under the inoculated soybean plants.

Foliar application of micronutrients caused significant increases in plant DW, LA, pod and seed number/plant, seed index and seed yield of fertilized and inoculated plants.

Foliar application of urea, to inoculated and uninoculated plants, caused significant increments in plant dry weight, 1A, seed protein content and particular seed index and seed yield.
Effect of Diclofop and Linuron on Rye Grass (Lolium multiflorum), Control in Triticale (X Triticosecale), Wheat (Triticum aestivum), and Rye (Secale cereale)
Authors: Bishnoi U. R. , Pancholi D. K.
Published: April 2008

Annual rye grass (Lolium multiflorum Lam.) is a serious and wide spread problem in cereal crops. A field experiment with a promising herbicide diclofop [(±)‐2‐[4‐(2,4‐dichlorophenoxy)phenoxy] propanoic acid] at 0.56, 0.84 and 1.12 kg ai/ha, in comparison to commonly used linuron [N'‐(3,4‐dichlorophenyl)‐N‐methoxy‐N‐methylurea] at 0.84, 1.12 and 1.41 kg ai/ha was conducted to control rye grass (Lolium multiflorum Lam.) in triticale (X Triticosecale Wittmack), wheat (Triticum aestivum L.) and rye (Secale cereale L.). The herbicides were applied as soil‐incorporated, preemergence and post‐emergence. Results showed that diclofop is less phytotoxic than Linuron and the postemergence application of these herbicides was more phytotoxic on all cereal crops. Diclofop applied at 1.12 kg/ha, gave almost 100 percent rye grass control and produced 45 and 115 kg/ha higher grain yields in pre‐ and postemergence methods, respectively, as compared to the soil‐incorporated method.
Inter‐cropping and Border‐cropping of Compatible Crops in Finger Millet (Eleusine coracana Gaertn.) under Garden Land Conditions
Authors: Siddeswaran K. , Ramaswami C.
Published: April 2008

With a view to explore the possibility of developing the most economic and viable intercropping and border‐cropping systems with nitrogen management in finger millet, an experiment was conducted at Tamil Nadu Agricultural University, Coimbatore, India during summer season (December—March) under garden land condition. Different inter‐crops tested were sorghum, sunflower, lady's finger, onion and cluster beans. The study indicated that intercropping and border‐cropping in direct sown finger millet under irrigated condition were possible. The best and most remunerative border‐crop as well as inter‐crop in finger millet was onion. Application of 90 kg N/ha would be sufficient for such a cropping system in a sandy clay loam soil of medium fertility. Onion and cluster beans exhibited companion effect and sunflower and sorghum exerted competitive effect on growth and production of finger millet.
Leaf Permeability and its Relationship to Grain Yield and Dry Matter Production in Oats, Avena sativa L.
Authors: Bertholdsson N. O.
Published: April 2008

The leaf permeability of eighteen field grown oat cultivars was examined with the aid of a viscous‐flow porometer. The relationship of leaf permeability to grain yield was determined during two different years. An F4 population and its parents were further studied for frequency distribution of leaf permeability, total plant dry matter, and grain yield. A plus and minus selection based on leaf permeability measurements was also studied.

Leaf permeability proved to be cultivar specific, i.e. a cultivar with low values one year also exhibited low values next year and vice versa (rank correlation r = 0.55, p < 0.05). This in spite of that one year was dry and the other wet. Old cultivars had low leaf permeability while new cultivars and new promising breeding lines had, with one exception, high values. Leaf permeability was positively correlated with grain yield, particularly during the wet year (r = 0.70, p < 0.001). The population had a population mean of 1.09 porometer units compared to 0.95 and 1.18 porometer units for the parents (LSD = 0.08, p < 0.05). Both total dry matter and grain production were positively correlated (p < 0.001) with leaf permeability during grain‐filling. The plus and minus selection for leaf permeability within a population showed in the next generation significantly different population means (0.69 and 0.79 porometer units, LSD = 0.08, p < 0.05). Total dry weight and grain yield were six per cent higher (non significant) in the plus selection than in the minus selection. The possibility to use leaf permeability as a selection criterion is discussed.
Recovery of Faba Bean (Vicia faba L.) Plants as Affected by Glyphosate
Authors: Shaban Sh. A. , El‐Hattab A. H. , Hassan Esmat A. , Abo‐El Suoud M. R.
Published: April 2008

Two field experiments were carried out during 1982/83 and 1983/84 seasons at Experimental Farm of National Research Centre at Shalakan, Kalubia Governorate, Egypt, to study the reversal effect of glyphosate induced phytotoxicity on growth and yield and its components of faba bean by the application of growth factors, i.e., growth regulators, amino acids and nutrient elements at different concentrations. A split plot design with four replications was used in both seasons. The obtained results indicated clearly that: Glyphosate at the two higher doses exhibited varying degrees of phytotoxic symptoms and reduced all the faba bean plant characters except the number of branches/plant. GA3 alone or in a mixture with cytokinin reversed the phytotoxic effect of the glyphosate herbicide on decreasing the plant height. Cytokinin at 4/1000, phenylalanine and tryptophan at both levels, as well as GA3 at 50 ppm, reversed the phytotoxic effect of the glyphosate herbicide on decreasing the dry weight/plant cytokinin at 4/1000, tryptophan at both concentrations, as well as, phenylalanine at 500 ppm, reversed the phytotoxic effect of the glyphosate herbicide on decreasing the number and dry weight of pods, seed yield per plant and per ha.
An Analysis of Conditions Determining Decline in Water Potential and Concurrent Proline Accumulation in Leaves of Four Cultivars of Vicia faba L.
Authors: Venekamp J. H. , Grashoff C. , Koot J. T. M.
Published: April 2008

Field bean plants, Vicia faba L., in the field were used to study which conditions determine decline in leaf water potential (ΨW) and coinciding proline accumulation. Cultivars Minica and Optica, having a short period of elongation growth, were used and the cultivars Alfred and Kristall, with a long elongation growth period. The plants were exposed to a “dry” and a “moist” treatment in a randomized block design. Leaf ΨW proline concentration and rate of elongation growth were measured weekly in June and July of both years. The measurements and samplings were conducted from 6 a.m. to 6 p.m. at 4‐hour intervals. Some leaf samples were selected for amino acid analysis.

It was concluded that a drought‐induced proline accumulation only occurred when the plants were still in the phase of elongation growth. In this phase, a pre‐dawn leaf ΨW lower than ‐2 bars, combined with high temperatures during the night, were the main determinants for this accumulation. Weather conditions in day time were less decisive for proline accumulation at a certain leaf ΨW decline. The same applies to the diurnal rhythm in physiological patterns, the genetic properties of the plants, the rate of leaf ΨW decline and the amino acid metabolism. Proline accumulation increased when two or more determinants acted together.
Specific and General Adaptation and Yield Stability of Wheat (Triticum aestivum L.) Genotypes
Authors: Musaviun M. , Ehdaie B.
Published: April 2008

Mean grain yield performance of 12 wheat and one triticale genotypes were measured at four locations over four consecutive years, using a randomized complete block design with four replications. The genotypes used were commercial cultivars and advanced lines from different wheat breeding projects located in different areas in Iran. Two locations were in semiarid regions and the other two locations in the temperate zones.

The combined analysis of variance indicated highly significant genotype‐environment (GE) interactions. From combinations of locations and years three sets of environments were generated. Set I and set II, each, consisted of eight environments (two locations and four years) representing semiarid and temperature environments, respectively. Set III consisted of 16 environments including both semiarid and temperate conditions. Set I and set II were used to measure specific adaptation of the genotypes while set III was employed for measuring general adaptation.

The methods of Eberhart and Russell (1966) were used for partitioning GE interactions. The mean square associated with the heterogeneity of regression was highly significant under all sets of environments. These observations indicated that a major part of GE interaction could be accounted for by differences in the regression of the individual genotypes.

All the genotypes had significant regression mean square under set I, set II, and set III environments, with the exception of two genotypes under set II. However, mean yields, regression coefficients, and the mean squares associated with deviation from regression greatly varied over the sets of environments.

Only three genotypes, a commercial cultivar and two new advanced line, were identified as having specific adaptation and yield stability to semiarid environments.

Among all the genotypes, only a commercial cultivar was identified as adapted and stable to temperate conditions. Two of the three genotypes which were adapted to semiarid environments also showed general adaptation to set III environments. However, the mean yield of these two genotypes under semiarid conditions (set I) were significantly greater than their respective mean yields under set III environments. Thus, wider adaptability was compensated by lower mean yield.

The present study indicates that, while a wide range of environments is necessary and recommended for measuring general adaptation reactions and yield stability of various genotypes, one should not ignore the possibility of finding some genotypes with specific adaptation to specific environments and thus maximizing yield production. Stable genotypes with general of specific adaptation should be utilized in breeding projects in order to develop even more desirable lines.
Growth Regulation in Crop Plants with New Types of Triazole Compounds1)
Authors: Jung J. , Luib M. , Sauter H. , Zeeh B. , Rademacher W.
Published: April 2008

BAS 110 … W and BAS 111 … W are introduced as new triazole‐type plant growth regulators. Most probably, the principal mode of action of both compounds consists in reducing the endogenous levels of biologically active gibberellins, thereby inducing shorter stems. The risk of lodging can be reduced in particular by BAS 110 … W in cereals and by BAS 111 … W in oilseed rape. Apart from this, pronounced increases in seed yield are obtained which are most probably due to the following effects: improved canopy structure, delayed senescence of leaves, improved partitioning of assimilates, enhanced root growth, reduced fungal infections and a lowered susceptibility to low temperatures and drought.
Persistence of Legumes in Hill Land Pasture Following Sod Seeding
Authors: Bryan W. B.
Published: April 2008

Unimproved hill land pastures are often characterized by low production and poor forage quality. The introduction and persistence of a legume component in the sward may increase both forage quality and quantity. Persistence of red clover (Trifolium pratense L.), birdsfoot trefoil (Lotus corniculatus L.) and white clover (T. repens L.) sod‐seeded into a rotationally grazed hill land pasture was examined. Legumes were introduced by broadcasting by hand, sod‐seeding with a zip seeder, and sod‐seeding with a Power‐till seeder. The effects of paraquat (1, 1‐dimethyl 4–4′‐bipyridinium ion), lime and P on legume persistence also were examined. The pasture was mostly Kentucky bluegrass (Poa pratensis L.) with 5 % white clover initially. Percentage legume in the pasture followed the same trend over time irrespective of whether sod‐seeded or not, or method of sod‐seeding. There was 30 % legume in control plots the year after sod‐seeding and 15 % at the end of 4 years. Application of lime and P resulted in an increase in legume content of at least 5 % through the 4 year period. Paraquat, legume species, and sod‐seeding method had no effect on legume persistence. It is concluded that management, soil fertility and time are the most important determinants of legume persistence in hill land pastures.
Optimization of Size and Shape of Experimental Plots for Trials Against Eggplant Fruit Borer, Leucinodes orbonalis Guen 1
Authors: Rao G. S. Prasada , Tewari G. C.
Published: April 2008

Studies were made to work out the optimum size and shape of the plots for conducting field trials against Leucinodes orbonalis Guen which is a serious pest of eggplant throughout South East Asia and Africa. A plot with 20 plant stand measuring 7.2 m2 was found to be optimum size based on the cv.‐% values. The shape of the plot was not considered to be important. The index of infestation heterogeneity (b) was high (> 2) indicating uniform spread of infestation throughout the field.
Effects of Nitrogen Fertilization on Yield and Yield Components of Tropical Maize Cultivars
Authors: Thiraporn R. , Geisler G. , Stamp P.
Published: April 2008

Six tropical maize cultivars were grown in Thailand on a reddish brown latosol under three nitrogen regimes, 0, 40 and 80 kg N/ha. With regard to biomass and economic yield several “cultivar by N fertilization response types” were discriminated. The low fertilization type was represented by an early and a late maturing cultivar, both yielded comparatively well without additional N and responded little to N fertilization. An opaque 2 cultivar and a commercial hybrid belonged to the high fertilization type, they had a very low yield without N and needed high N fertilization to produce a high yield. The other genotypes were of an intermediate type with comparatively high yields without N, a considerable increase in yield at 40 kg N/ha and some increase from 40 to 80 kg N/ha. Genotypic variability for the harvest index was high but values were at the usual low level of tropical cultivars. High fertilization types reacted to an additional N supply with a marked increase in kernel number/plant and little increase in kernel weight. The early maturing low fertilization type reacted quite the opposite way. All other genotypes predominantly increased kernel number from 0 to 40 kg N/ha and kernel weight from 40 to 80 kg N/ha.
Effect of Two Row Spacings and Hemp Sesbania Competition on Sunflower
Authors: Woon C. K.
Published: April 2008

The competitiveness of hemp sesbania (Sesbania exaltata [Raf.] RYBD. EX A. W. Hill) with sunflower (Helianthus annuus L.) grown in two row spacings was evaluated at the University of Arkansas at Pine Bluff Agricultural Experiment Station in 1982 and 1983. Sunflower and hemp sesbania at densities of 3 to 5 and 13 to 16 plants per meter row, respectively, were interseeded in 61 and 91 cm row spacings in field test plots. Hemp sesbania plants were removed at different sunflower growth stages. In 1982, weed removal treatments were: (1) weedy check, (2) weed‐free check, (3) weed removal at 15‐leaf stage, (4) removal at 20%, (5) 50% and (6) 100% sunflower anthesis. Treatments in 1983 consisted of: (1) weedy check, (2) weed‐free check, (3) weed removal at 10‐leaf stage, (4) bud stage, (5) pre‐anthesis, (6) 10% anthesis, and (7) 100% anthesis. Sunflower yields were significantly decreased by hemp sesbania competition each year, except for the weed competition treatments in 91 cm row spacing in 1982. Generally, the longer the weeds were allowed to compete with sunflower, the greater the sunflower yield reduction. Yield reductions of 5% to 6% and 25% or more were observed when hemp sesbania was allowed to compete with sunflower until the 10‐leaf and anthesis stages of sunflower growth, respectively. When hemp sesbania was allowed to compete with sunflower for the entire growing season, yield was reduced by as much as 35%. Reducing row width from 91 cm to 61 cm did not improve sunflower's ability to compete with hemp sesbania. Thus, hemp sesbania is quite competitive with sunflower and should be controlled during early vegetative growth in order to minimize yield loss.
Effect of Variety and Seeding Rate on Establishment and Productivity of Alfalfa Sown in Autumn
Authors: Sarraj W. M.
Published: April 2008

Five alfalfa varieties (var.) were sown on 26 September, 1983 near Aleppo on clay or heavy clay soils, classified as Vertisols (FAO‐system) or Chromoxerertic (Calcic) Rhodoxeralf (USDA‐system). Irrigation was applied after planting to ensure uniform germination. Thereafter the study was conducted under supplementary irrigation. The parameters measured to estimate fresh weight (FW) and dry matter (DM) yields; plant height, ground cover and regrowth after cutting, indicated that winter‐active var. (Moapa 69, CUF 101 and Aleppo local) resulted in better productivity than semi‐dormant (Paravivo) and dormant (Lebanon local) varieties. The 2‐years mean average FW yields were 70.2, 68.2, 65.2, 57.1 and 36.9 t/ha, or 16.2, 16.0, 15.5, 13.1 and 8.9 t/ha DM respectively. Forage yields were similar among the 12, 16 and 20 kg/ha seeding rates, indicating little justification for high seeding rates under good establishment conditions, even if a seeding‐year yield is desired. In general, seeding rate had also no effect on plant population, which was reduced with time and towards the end of the tested period it became nearly similar and counted 137, 132 and 134 plants/m2 according to the seeding rates respectively. Alfalfa yields were positively correlated with plant height, ground cover and regrowth after cutting. The highest yielding combination for FW and DM yields in Moapa 69 with 12 kg/ha seeding rate.
Effect of Leaf Sugar and Starch Concentrations on Apparent Photosynthesis in Alfalfa
Authors: Travis R. L. , Prendergast J.
Published: April 2008

Rates of apparent photosynthesis (AP), dark respiration, photorespiration, mesophyll resistance, and concentrations of soluble starch, sugars, chlorophyll and nitrogen were measured in alfalfa leaves (Medicago sativa L.) grown under high or low light levels in an attempt to evaluate the effect of nonstructural carbohydrate concentration on net CO2 assimilation.

Leaf N and chlorophyll levels of high light plants exceeded those of low‐light plants. Constant light increased both starch and sugar levels in low‐light plants, but had little effect on high‐light plants. Rates of AP declined in low‐light plants upon transfer to constant light conditions, apparently due to increases in stomatal and mesophyll resistance. Leaf starch levels were negatively correlated (P > 0.05) with rates of AP and positively correlated with mesophyll resistance in both groups of plants but leaf sugar content was not correlated with either AP or mesophyll resistance.

Starch and sugar levels of high‐light plants declined substantially upon transfer to constant darkness, while low‐light plants were less affected. Rates of AP declined in both groups of plants due to increases in both mesophyll and stomatal resistances. Neither sugar nor starch levels were correlated with AP or mesophyll conductance in this treatment.

The data support the hypothesis of feedback inhibition of photosynthesis, mediated through an increase in mesophyll resistance, which is associated with high levels of starch in the leaves.
Role of Fine Roots in the Nitrogen Economy of Sugar Beet
Authors: Steen E. , Lindén B.
Published: April 2008

In 31 field experiments with sugar beet, carried out in 1982–84 in Scania, southern Sweden, fertilizer nitrogen recovery in tops and beets, calculated with the difference method, amounted to 73%. To elucidate the role of the fine lateral roots in the fate of the nitrogen not accounted for, the lateral roots within depths of 0–25 and 25–60 cm were sampled at harvest in late September, 1984 in five sugar beet experiments. Irrespective of differences in nitrogen fertilization and plant‐available soil nitrogen, a mean of ca. 3 kg/ha−1 of nitrogen was found in the fine lateral roots. This corresponded to only ca. 2% of the nitrogen in the whole crop at harvest, whereas the beets and tops contained 43 and 55%, respectively. Using the difference method, calculations with, as well as without, fine roots therefore yielded the same recover (75%) of fertilizer nitrogen in the beet crop. The increase of residual mineral nitrogen in the soil at harvest caused by the fertilization corresponded to 2% of the fertilizer nitrogen applied. This means a total recovery of 77%.
Effect of Simulated Lodging on Soybean Yield
Authors: Shapiro C. A. , Flowerday A. D.
Published: April 2008

Soybean (Glycine max [L.] Merr.) grain yields may be reduced when the plants lodge. The magnitude of yield reduction is dependent on the growth stage at which lodging occurs. The stage of plant development most vulnerable to yield reduction from lodging has not been conclusively determined. The objective of this two‐year study was to determine soybean yield reduction caused by simulated lodging at three stages of reproductive development: the onset of flowering (R1), beginning pod (R3) and beginning seed (R5). At each developmental stage the plants were lodged at either 45° or 90°. A natural lodging control and an artificially maintained erect treatment were included.

The 1976 results indicated no yield differences due to any of the lodging treatments. In 1977, yields were significantly reduced for the R3 lodging treatments. Soybeans lodged 90° at the R1, R3, and R5 growth stages yielded 2.63, 1.88 and 2.26 Mg ha−1, respectively. The natural lodging and erect treatments yielded 2.73 and 2.43 Mg ha−1, respectively.

Lodging treatments applied at the R1 stage produced plants with a two‐year average of 30% of their seeds on the main stems, compared to 62% of the seeds on the main stems for the R5 stage treatments. The percentage of seeds on the main stem was 69% on the erect plants, as compared with 45% on the 90° lodged plants. In 1977, lodging treatments also reduced pods per plant, seeds per plant, 100 seed weight and seed weight per plant.
Micrometeorological Influences at High Crop Density on Different Genotypes of Silage Maize
Authors: Hoyningen‐Huene J. V. , Wermke M.
Published: April 2008

In the year 1979, 1981 and 1982 two‐factorial experiments with the factors genotypes and crop densities were conducted, connected with the following agrometeorological analyses:

a) outside the canopies: determination of air temperature, air humidity, wind velocity, precipitation, global radiation and photosynthetically active radiation (PAR)

b) in the interior of the canopies: measurements of air temperature at cobheight, of precipitation components, of the penetration of PAR and of the leaf area index.

The following results were obtained:

a) Influence of high crop densities

1. In high crop densities the greatest part of radiation was absorbed, so that at 30 plants/m2 57% and at 70 plants/m2 only 28% of the PAR reached cob height.

2. As a consequence of temperature and decrease of radiation the contents in the leaves of biological energy, of water soluble K.H. and rough protein were reduced.

b) Influence of the leaf posture

3. For genotypes with erected leaf posture the leaf temperatures increased by 0.3°C, on the ground even by 1.2°C above the values of the stand with horizontal leaf posture.

4. Higher air temperatures were measured in the stands with erected leaf posture than in those with a horizontal one.

5. In the cool year 1981 on days with temperatures above 27°C outside the stands, those temperatures were exceeded during 7 hours in canopies with erected leaf posture at a higher plant density (30 plants/m2) and only during 2 hours in canopies with a horizontal leaf posture.
Containers for Small‐Plot Trials with Crop Plants
Authors: Keller E. R. , Huber R. , Schwendimann F. , Soldati A.
Published: April 2008

A description is given of a PVC‐container installation which allows the determination of plant yield as well as the measurement of water flow. The single containers with 600–700 kg soil are transportable by means of a fork‐lift truck or similar vehicle. Information is given on the insulation and the heating unit (overwintering) of the container as well as on the elimination of border effects, fluctuations in soil temperature etc. An example of practical use, a trial with 48 units with the aim of evaluating the BNF (closed system) of faba beans in a rotation, is described. Detailed instructions (English, French, German) for constructing the container unit are available from the authors.
Effect of Boron on Seed Yield in Lucerne (Medicago sativa L.)
Authors: Misra S. M. , Patil B. D.
Published: April 2008

The present study aimed at studying the effect of boron on pollen characteristics, translocation of water soluble sugars and its importance as a specific nutrient for seed production in lucerne. Aquous solutions of borax (0, 2500, 5000, 7500, 10 000 and 20 000 ppm) were sprayed at flowering stage. After 20 days, the fresh flowers were collected from the plants of all the treatments separately. The pollen was dusted on glass slides containing Muntzing's mixture for staining. After 6 hours, the data on pollen size, stainability and germination were recorded in 10 randomly selected microscopic fields. The estimation of water soluble sugars and boron content in flowers was done by standard methods. Data on grains per pod, grains per inflorescence and 1000 seed weight were recorded at seed maturity. With increasing rates of applied B, pollen germination, water soluble sugars, boron content and number of seeds per pod and per inflorescence increased but pollen fertility decreased. The pollen size and 1000 seed weight was not affected by boron concentrations. The results indicate that boron plays a definite role in increasing the seed yields through stimulating the physiological processes during reproductive phase.