bluuebunny/crossref_metadata_2025 huggingface dataset:
The Nutritive Value and Yield of Alfalfa in Relation to Nitrogen Fertilization on Sulphur Industry Reclaimed Lands
Authors: Pucekand T. R. , Pys J. B.
Published: April 2008

The yield and nutritive value of alfalfa (Medicago sativa L.), cultivated together with grasses under conditions of various nitrogen fertilization with simultaneous excess of potentially available sulphate sulphur in subsoil, were determined. The study was carried out on reclaimed lands of sulphur bore‐hole mine. The levels of basic nutrients, total sulphur and selected micro‐ and macro elements were determined. The relations between mineral constiruents were calculated, taking into account particularly Nt:St and Ca:P ratios. No significant differences were found between average yields of alfalfa biomass obtained with various nitrogen treatments. Average contents of total nitrogen, true protein and non‐protein nutrients (NPN) as well as Ca:P ratio showed significant differences between varied levels of nitrogen fertilization (P < 0.05). The nitrogen fertilization above an application rate of 25 kg N ha‐1 caused a decrease in crude protein level, an increase in non‐protein nutrient content and a reduction of true protein percentage in total protein fraction. A deficiency of potassium and phosphorous in soil as well as in dry matter of alfalfa was stated. The potassium content in alfalfa was linearly negatively correlated with the accumulation of non protein nutrients (P < 0.01). The accumulation of total sulphur and selected micro elements in alfalfa did not exceed the permissible forage levels.
Effects of Timing of Drought Stress on Abscission and Dry Matter Partitioning of Short‐duration Pigeonpea
Authors: Lopez F. B. , Chauhan Y. S. , Johansen C.
Published: April 2008

Shoot dry mass partitioning and cumulative abscission of leaf, flowers and pods were determined for nine short‐duration pigeonpea genotypes grown with adequate soil moisture throughout growth (control), or subjected to water stress during the late vegetative and flowering (stress 1), flowering and early pod development (stress 2), or pod fill (stress 3) growth stages. The total cumulative dry mass of abscised plant parts was lower for determinate genotypes, but it increased to a greater extent under water stress than that for indeterminate genotypes, with stress 2 having the greatest and stress 3 die least effects. The dry mass contribution of pods to total abscission was ≤ 5%, and not signiflcantiy affected by water stress, while the contribution of leaves increased and mat of flowers decreased. Stress 3 had no significant effects on abscission dry mass totals or components. Reduction in shoot dry mass under water stress was most pronounced for genotypes in die early pod development stage, and the dry mass contribution of leaves generally decreased and that of pods increased under stress 1 and stress 2. With similar abscission levels, the shoot dry mass of genotype ICPL 151, was similar to, or greater than, that of hybrid ICPH 9, under stress 1 and stress 2, and the contribution of pods to shoot dry mass was lower for hybrid ICPH 9 under both stress treatments. Genotypic differences in drought resistance were likely due to differences in the leaf area maintenance during, and in the recovery of dry mass and pod production following, water stress periods.
Die Ertragsentwicklung von Wintergetreide und Zuckerrüben bei dauerhafter Senkung des N‐Düngungsniveaus
Authors: Becker K.‐W. , Bruss A.
Published: April 2008

Effects of Long‐term Fertilizer N Reduction on Winter Grain and Sugar Beet Yields

The results of recent field experiments concerning the effect of long‐term N‐reduction on the yield and quality of sugar beet, winter wheat and winter barley on plots which had previously had received ample amounts of N are studied in this paper.

The yield and quality of crops harvested on plots where N‐dressings had been reduced for 6–8 years were similar to those of crops grown on plots where N‐application had been reduced for only 1 year. Grain yield of winter wheat and winter barley grown without any N‐application decreased to about 60 % of amounts normally harvested under local conditions with recommended N dressings, whereas the white sugar yield still remained at 90 %. The yields decreased slightly with an increase in the duration of the experiments. Yields of both cereals and beets remained constant within each level of fertilization, even 6 years after inition of trials with 50, 75 and 125 % of locally recommended N dressings.

On plots that did not receive nitrogen fertilization, N‐contents of grain were between 1.5 and 1.7 % for winter wheat and 1.0 and 1.6 % N for winter barley. These contents remained constant over a trial period of 6 years. The amount of annual export of 55–91 kg N/ha also remained constant. Limited N availability causes a decrease in grain protein content rather than in grain yield.

Compared to winter grain species, sugar beet (with 74–117 kg N/ha in the beet body) could realize the highest annual export of nitrogen from the plot. Differences in annual N export existing between the various locations of the plots cannot be explained by differences in soil quality. Continuous high yields that were found even without any N‐dressings may be explained by asymbiotic N‐fixation, deposition of atmospheric N and a progressive decrease in soil N with 17–56 kg N/ha removed from soil resources annually.
β‐Glucangehalt in den Karyopsen von Hafersorten in Abhängigkeit des Anbaujahres und der Stickstoffversorgung
Authors: Baur S. K. , Geisler G.
Published: April 2008

β‐glucan content in caryopses of oat varieties with regard to cultivation year and nitrogen level.

The positive effects of (1–3), (1–4)‐β‐D‐glucans on the health of human beings gave reason to investigate the production of these compounds in caryopses of oat and their dependence on genetic and environmental conditions. The caryopses of 18 German oat varieties and the effect of three nitrogen rates were tested for 2 years. The β‐glucan content (% DM) depends on the oat variety and is influenced by prevailing climatic conditions during the test year. With increasing nitrogen fertilization, the β‐glucan content (% DM) increases. The β‐glucan‐ranking of oat varieties is more or less stable in different environments.
Performance of Selected Strains of ‘Farro’ (Triticum monococcum L., Triticum dicoccum Schübler, Triticum Spelta L.) and Durum Wheat (Triticum Durum Desf. cv. Trinakria) in the Difficult Flat Environment of Southern Italy
Authors: Codianni P. , Ronga G. , DI Fonzo N. , Troccoli A.
Published: April 2008

The aim of this study was to evaluate the performance of three species of unhulled‐wheat (Triticum monococcum L., Triticum dicoccum Schubler and Triticum spelta L.) with respect to durum wheat (Triticum durum Desf. cv. Trinakria) in southern Italy's flat environment.

As far as yield is concerned, the mean yield was significantly different among species. Durum wheat yielded 16.1 %, 37.6% and 69.5 % more than dicoccum, spelta and monococcum species, respectively.

Among unhulled‐wheat species, only Triticum dicoccum showed some similarity with durum wheat, such as one‐thousand kernels weight, plant height and number of spikes per m2.

Among the factors studied, the days to reach heading represented the factor that mostly influenced yield
Temperature Effects on the Duration of the Spikelet Growth Phase and Spikelet Abortion in Barley
Authors: Kernich G. C. , Halloran G. M.
Published: April 2008

Above optimal temperatures in cereals, when measured in thermal time units (°Cd) can lead to underprediction of developmental events by models, particularly when cereals are sown late in Mediterranean‐type environments or grown under subtropical conditions. Our objective was to assess the effects of high temperatures on the length of the spikelet growth phase, the number of spikelet nodes per spike and level of spikelet abortion in spring barley (Hordeum vulgare L.). The spikelet growth phase (from the end of the spikelet initiation phase to anthesis) of three cultivars, ‘Bandulla’, ‘Schooner’ and ‘Weeah’ was subjected to two temperature regimes. In the first of two sowings, the mean daily maximum temperature for one regime was 24 °C (maintained for 6 h daily) and the mean daily minimum was 8 °C (24/8 °C). The second temperature regime was 27/17 °C. Corresponding temperatures for the second sowing, which was subjected to slightly longer photoperiods, were 26/8 °C and 26/17°C, respectively. The duration of the spikelet growth phase was longer for 27/17 °C than for 24/8 °C in the first sowing when measured in calendar time (d). In the second sowing, the duration of the spikelet growth phase was slightly shorter under the higher temperature regime (d). The duration of the spikelet growth phase (in°Cd) was greatly increased by the higher temperature treatment in both sowings. In the first sowing, the percentage of aborted spikelets was greater at HT than at LT for Bandulla and Weeah at both sowing times and the duration of the spikelet growth phase increased with higher night temperatures, suggesting that length of the spikelet growth phase was not the sole factor responsible for the proportion of aborted spikelets.
Effect of Split Nitrogen Application on Growth and Yield of Wheat (T. aestivum L.) Genotypes with Different N‐Assimilation Potential
Authors: Abdin M. Z. , Bansal K. C. , Abrol Y. P.
Published: April 2008

A field experiment was conducted with different nitrogen regimes to assess the growth and yield performance of wheat genotypes which differ in nitrate assimilation potential. Genotypic differences in biomass accumulation were observed at different growth stages. The nitrogen treatment had little effect on biomass accumulation at early stages of growth, while at later stages of growth there was enhanced biomass accumulation when N was applied in more than two splits. On an average, genotypes with high nitrate reductase activity (the ‘HNR’ genotypes) accumulated 14.2 % more biomass than the genotypes with low nitrate reductase activity (‘LNR’ genotypes) when an extra dose (40 kg N ha−1) of nitrogen was given at the time of anthesis. The application of nitrogen in more than two splits increased grain yield of both ‘HNR’ and ‘LNR’ genotypes mainly by increasing grain weight per ear. The application of an extra dose of nitrogen (40 kg N ha−1) at the time of anthesis increased grain yield of ‘HNR’ genotypes by 38.5 % as compared to ‘LNR’ genotypes.
Effects of Low Temperature Treatment at Seedling Stage on Soybean Growth, Development and Final Yield
Authors: Skrudlik G. , Kościelniak J.
Published: April 2008

The after effect of continuous and variable chilling temperatures acting periodically for 7 days at seedling stage (day/night: 2/2°C, 5/5°C, 15/2°C, 15/5°C, 15/15°C and control–22/18°C) on growth, development and final yield of soybean cultivar Polan and Progres were investigated. The temperature decrease lengthened the duration of the vegetation period before flowering for both cultivars, which allowed compensation for the reduced–as an effect of chilling–rate of daily increments in the leaf area and the dry weight of the above‐ground parts of the plants. The most important symptom of chilling treatment was a considerable increase in the number of axillary branches after flowering, which caused an increase in the dry weight of plants. The subsequent reaction of the growth of leaves to chilling at seedling stage was, after flowering, variety dependent. The area of leaves bigger at Polan or similar to control at Progres ensured good seed filling in an increased number of pods developed on axillary branches. Chill‐induced delay in plants development allowed the avoidance of low temperature occurring during flowering in this experiment. This chilling during flowering was one of the reasons of worse‐pod setting and reduction of seeds per pod number at control plants.
Relation Between Pattern of Development of Wheat Seedlings and Growth Rate of Leaves, Tillers and Roots
Authors: Schipper J.
Published: April 2008

Relation between pattern of development of wheat seedlings (Triticum aestivum L. Fiori et Paol.) and growth rate of leaves, tillers and roots.

In two glasshouse and two phytotron experiments, the early growth and development of spring wheat and unvernalized autumn wheat in long and short days was observed by frequent assessments of dry weight of shoots and roots and by daily measurements of length and dry weight of individual leaves. In an additional experiment, the pattern of dry matter distribution during germination was studied.

The rate of leaf emergence and appearance was decelerated by short days in spring wheat and by long days in unvernalized autumn wheat.

The growth rate of individual leaves showed a pattern of successive reductions and accelerations, being highly synchronized between leaves and clearly related to the succession in emergence of leaves and tillers.

Growth rates of main shoot and tillers were apparently synchronized, while those of the seminal root system appeared to show an oppositional pattern as compared to the shoot.

It is suggested that variation in the growth rate of existing organs is based on hormone controlled variation in meristematic activity, which is influenced by day length and the state of vernalization of the plant.
Effects of Light, Different Growth Media, Temperature and Salt Concentrations on Germination of Cotton Seeds (Gossypium hirsutum L. cv. Nazilli 87)
Authors: Tort N.
Published: April 2008

Laboratory experiments were conducted to study the effects of light, different growth media, temperature, and salt concentrations on the germination ratio, mean germination period, and the beginning of germination of cotton seeds, Gossypium hirsutum L., cv. Nazilli 87. All factors considerably affected the germination rate of cotton seeds, ranging from 47% at darkness to 96% at 16 h of artificial light. The mean germination period varied from 5.6 days at 15°C and 1.3 days at 30°C under illumination and lasted longer at dark. The germination ratio was 94 % without additional salt and decreased from 63 % at salt concentration of 175 mM NaCl 1−1 to only 8.7 % at 300 mM 1−1. The mean germination period ranged from 5.28 days to 13.50 days at salt concentrations of 0–300 mM NaCl l−1, respectively.
Respiration and Growth of Sorghum and Sunflower under Predicted Increased Night Temperatures1
Authors: Manunta P. , Kirkham M. B.
Published: April 2008

Little information exists concerning how crops will respond to the predicted increased night temperatures. The objective of this work was to determine if respiration and growth of sorghum [Sorghum bicolor (L.) Moench], a C, plant, and sunflower (Helianthus annuus L.), a C3 plant, are affected when the night temperature is increased by 5°C compared to the long‐term (19 year) average night temperature in June in Kansas. Sorghum and sunflower were grown in two walk‐in growth chambers with either the ambient night temperature (21C) or a high night temperature (26C). Day temperature was the same for all plants (27C). Both sunflower and sorghum had higher respiration rates under the elevated night temperature than under the ambient temperature. The average respiration rate of sunflower grown under elevated night temperature increased by 19% (0.89 vs. 0.75 μmol m−2 s−1) and that of sorghum by 44 % (0.52 vs. 0.36μmol m−2s−1). After 74 days, sunflower plants grown under the ambient night temperature were 30.2 cm taller than sunflower plants grown under the elevated night temperature; sorghum plants under the ambient temperature were 24.8 cm taller. Sunflower plants grown under the elevated night temperature formed flowers one week earlier than those grown under the ambient temperature. Sorghum formed no flowers by 74 days. Results suggest that, if climate change does increase night temperature, respiration will be increased more in C4, than C3 plants.
The Response of Sweet Potato (Ipomoea batatas Lam.) to Inter‐ and Relay‐cropping with Maize (Zea mays L.)
Authors: Oswald A. , Alkämper J. , Midmore D. J.
Published: April 2008

Four sweet potato cultivars were inter‐ and relay‐cropped with maize at two locations in Peru. Increasing interspecific competition drastically reduced tuber yields of all cultivars; fewer tubers m −2 were produced and no tolerant genotype was identified. Likewise the mean tuber weight declined linearly for two cultivars when competition became severe. Shoot development was less affected. Under intense competition the plant top was favoured in assimilate partitioning to the detriment of tuber formation. Overall reduction in assimilate production due to mixed cropping was the major cause of yield loss. Various intercropping combinations were found with the same productivity but distinct proportions of the component crops (sweet potato + maize). Land equivalent ratio (LER) exceeded sole crop productivity only for the combinations with the highest maize yields. Biomass production was clearly increased by intercropping but there was no increment in marketable yields. Relay‐cropping reduced tuber and maize yields and had the lowest productivity of all combinations tested.
Response of Rice Varieties Grown in Semi‐deepwater Ecosystem to Foliage Pruning and Nitrogen Fertilization
Authors: Sharma A. R.
Published: April 2008

Field experiments were conducted at Cuttack, India, in 1992 and 1993 using two semi‐tall (Panidhan and CR 580‐5 of 180 days duration) and two tall (Amulya and CR 626‐26‐2‐3 of 170 days duration), elongating and photosensitive rice varieties to study their response to foliage pruning at varying levels of nasally applied N fertilizer (0, 30, 60 and 90 kg N ha−1). Pruning at the collar level of the topmost leaf was done either once at 90 or 120 days of growth, or twice at both the stages. The crop was sown during the end of May in dry soil and subsequently grown under a semi‐deepwater regime (0–80 cm water depth). The dry weight of pruned foliage was more in the tall than in the semi‐tall varieties and it increased with an increase in the level of N fertilization and delay in pruning. Two prunings produced greater foliage yield than one pruning. Foliage pruning once at 90 days of growth had no effect on the grain yield of all varieties. However, pruning at 120 days of growth decreased the yield of Amulya and CR 626‐26‐2‐3, particularly in 1992, possibly because of less time (25–30 days) available for the crop recovery before flowering. Further, pruning twice at 90 and 120 days of growth reduced the grain yield of all the varieties significantly due to a reduction in their panicle weight. Application of N fertilizer beyond 30 kg N ha−1 did not increase the grain yield under no pruning treatment, but the crop responded significantly up to 60 kg N ha−1 under one pruning and up to 90 kg N ha−1 under two prunings, despite its adverse effect on crop performance. The crop lodging in response to increased N application was delayed by about a fortnight due to foliage pruning but its beneficial effect was not reflected in the grain yield. The results indicated that the green leafy foliage of the tall elongating rice varieties could be harvested 40–50 days before flowering for feeding the cattle without impairing their productivity under semi‐deepwater ecosystem.
Vererbung des β‐Glucangehaltes der Haferkaryopse
Authors: Baur S. K. , Geisler G.
Published: April 2008

Inheritance process for β‐glucan content in oat caryopsis

Due to the fact that there are only few studies concerning β‐glucans in oat caryopsis with regard to plant‐breeding aspects, three oat crosses were performed (cross 19 = low × high, cross 86 = low × low, cross 98 = high × high). In all of the three oat crosses, lower β‐glucan content (% DM) was recorded in F, than in F, indicating that the β‐glucan content (% DM) at a higher heterozygoty grade is lower than at a reduced heterozygoty grade. This points to a dominant inheritance of lower β‐glucan content (% DM). A tendency towards the female β‐glucan content (% DM) could not be proven. Thus, it can be started from a nuclear genetic inheritance of the β‐glucan content (% DM). In most cases, the experiments showed a normal distribution of β‐glucan content (% DM), indicating for several genes a quantitative inheritance of β‐glucan content (% DM). By means of the regression of the F3‐lines to the F2‐plants, the narrow‐sense heritability could be calculated for the cross 86 (h2= 0.51***) and the cross 98 (h2= 0.48***). The heritability for the cross 19 was not significant.
Effect of Defoliation on Growth and Physiological Developments in Tubers of Purple Nutsedge (Cyperus rotundus L.)
Authors: Marambe B.
Published: April 2008

The starch metabolism and hydrolytic enzyme activities in growing tubers of purple nutsedge (Cyperus rotundus L.) in response to defoliation were examined to elucidate the regrowth physiology of the plant. Effects of complete or partial defoliation imposed at 2 or 4 weeks (single defoliation), or 2 and 4 weeks (repeated defoliation) after emergence (WAE) on plant growth were studied.

Leaf area and leaf dry weight per plant in the control plots increased with time. In the mother tuber, dry weight and starch content were reduced by 16 % and 18 %, respectively, during the first 2 WAE, and then increased with time. Endoamylase (EC 3.2.1.1) activity of tubers (3.8 units g−1 dry tuber) increased by 42 % during the first 4 WAE, but decreased rapidly up to 8 WAE.

Repeated defoliation significantly reduced the regrowth ability of nutsedge tubers when compared to single defoliation and the control. Repeated complete defoliation reduced the leaf area and leaf dry weight by 56 % and 69 %, respectively. The dry weights of mother tuber and total tubers 100 cm −2 were reduced by 41 % and 63 %, respectively, when compared to the control at 8 WAE. Endoamylase activity and starch content in the mother tuber in this treatment were reduced by 72 % and 56 %, respectively. Defoliation did not have any significant effect on the exoamylase activity.

Endoamylase is the major starch hydrolysing enzyme in tubers and the activity of this enzyme could be a limiting factor in regrowth of nutsedge tubers. Repeated complete defoliation effectively suppressed the regrowth of purple nutsedge.
Grain Weight Reductions in Wheat Associated with Semidwarfism: an Analysis of Grain Weight at Different Positions Within the Spike of Near‐isogenic Lines
Authors: Miralles D. J. , Slafer G. A.
Published: April 2008

Semidwarf genes have made a major contribution to grain yield gains in wheat during this century. These genes have frequently been reported to increase grain number but decrease grain size. To analyse possible causes of this negative association between number of grains per head and mean grain weight, grains from different positions within the spikes were individually weighed in three isolines (standard‐height, SH; semidwarf, SD; and dwarf, DD) of the spring wheat cultivar Maringa grown under field conditions.

Dwarfing genes affected both grain number and grain weight. Increasing doses of Rht genes resulted in a decreased average grain weight (ca. 22 %) but in a greater increase in number of grains per m2 (ca. 40%). Since the isogenic lines did not differ in either the number of spikes per m2 or number of spikelets per spike, the frequencies of appearance of grains in the distal positions (florets 3 and 4) of the central spikelets and in the top spikelets of the spike was much higher for the SD and DD lines than for the SH line. Averaging across spikelets, basal grains (grains 1 and 2) of SH, SD and DD lines represented ca. 82, 73, and 69 %, respectively, of the total number of grains. On the other hand, grain 4 was almost absent in the SH line but represented around 10 % of the grains in the DD line.

Averaging across lines and spikelets, basal grains weighed ca. 30 mg, which is approximately 20 % heavier than grain 3 (ca. 25 mg) and 85 % heavier than grain 4 (ca. 16 mg). Although there was a clear trend for a greater grain weight in the SH line (with no major differences between the SD and DD line) when basal grains were considered, grains 3 and 4 did not show any clear difference between lines.

The fact that genotypes with Rht alleles had grains in the distal positions with a much higher frequency of appearance than in the SH line could be the main reason for their lower average grain weight. Therefore, the negative relationship between grain number and average grain weight might be not reflecting that competition for assimilates among grains of the DD and SD lines is stronger than that in the SH line.
Evaluation of Root Sink Ability of Sweet Potato (Ipomoea batatas Lam.) Cultivars on the Basis of Enzymatic Activity in the Starch Synthesis Pathway
Authors: Yatomi M. , Kubota F. , Saito K. , Agata W.
Published: April 2008

Activities of five enzymes, sucrose synthase (SUS), uridine 5′‐diphosphate glucose pyrophosphorylase (UDPGPPase), fructose‐1,6 bisphosphatase (FBPase), adenosine 5’diphosphate glucose pyrophosphorylase (ADPGPPase) and starch synthase (STS), in the metabolic pathway of starch synthesis, were compared between two sweet potato (Ipomoea batatas Lam.) cultivars, Koganesengan (C.V.KOG, a recently released high yield cultivar) and Tsurunasigenji (C.V.TSU, an old, local cultivar with poor yield). The measurements were carried out using the root samples (tuberous, thick and fibrous roots) harvested at the fast tubering stage. Of the five enzymes, SUS, ADPGPPase and STS showed high activities in the tuberous root, particularly in that of C.V.KOG, and a similar trend was observed for activities of these enzymes on a protein basis. The increased activity of the three enzymes is considered to be one of the characteristics in a high yield cultivar, allowing the root to function effectively as a starch synthesis and storage organ.
Effect of Depth and Method of Irrigation and Nitrogen Application on Herb and Oil Yields of Java Citronella (Cymbopogon winterianus Jowitt.) under Semi‐arid Tropical Conditions
Authors: Singh M. , Ganesha Rao R. S. , Prakasa Rao E. V. S.
Published: April 2008

A field expenment was conducted during 1992–94 at CIMAP, Field Station, Bangalore, India to study the effect of depth (25, 37.5 and 50 mm) and methods (Ridge and furrow and Broad Bed and furrow method) of irrigation and nitrogen levels (0, 200 and 400 kg N ha−1 year−1) on herb and oil yields of Java citronella. At the highest level of N application (400 kg N ha−1 year−1) ridge and furrow method was better suited for irrigating citronella. However, under lower N levels (0 and 200 kgN ha−1 year−1), as much as 30 % water can be saved by the broad bed and furrow method. The results have shown that highest herb and oil yields of citronella were achieved with the application of 400 kg N and maintaining 25 mm depth of irrigation. Content and quality of oil were not affected either by irrigation or nitrogen.
Effects of Timing of Drought Stress on Leaf Area Development and Canopy Light Interception of Short‐duration Pigeonpea
Authors: Lopez F. B. , Chauhan Y. S. , Johansen C.
Published: April 2008

Leaf area index (LAI), fractional canopy light interception (F) and plant mortality at maturity, were determined for nine short‐duration pigeonpea (Cajanus cajan [L.] Millsp.) genotypes in response to drought during the late‐vegetative and flowering (stress 1), the flowering and early podfill (stress 2), or podfill (stress 3) stages. LAI and F were reduced, but plant mortality did not increase under drought. Stress 2 reduced LAI to the greatest extent, consistent with the effects on seed yield. At the end of stress 1, seed yield was closely related to LAI for the different genotypes in stressed but not in unstressed (control) plots. Reductions in LAI due to reproductive growth were as great or greater than those due to water stress. Indeterminate genotypes had smaller but more leaves per plant compared to the determinate genotypes. The importance of these differences to drought resistance was not apparent. Production of leaves with decreasing specific leaf area throughout plant growth may be advantageous, especially when drought is likely to occur during reproductive growth. Values of F during and following water stress gave an indication of genotypic drought resistance, with the most drought‐sensitive genotype showing the largest reduction in F under water stress and the slowest rate of recovery following rewatering. For short‐duration pigeonpea, where plant mortality is not a factor under water stress, the maintenance of both LAI and F appears to indicate genotypic drought resistance.
Breaking Uniculm Growth Habit of Spring Cereals at High Latitudes by Crop Management. II. Tillering, Grain yield and Yield Components
Authors: Peltonen J. , Peltonen‐Sainio P.
Published: April 2008

Long days at high latitudes inhibit tillering of cereals and hence seeding rates of 500–700 seeds m−2 are commonly used for spring wheat, barley and oats in Finland. Costs could be reduced by using a lower seeding rate in combination with crop management to produce more head‐bearing tillers m−2. This study was designed to assess possibilities of breaking the uniculm growth habit of spring cereals by (1) lowering the seeding rate from 600 to 300 seeds m−2 and (2) manipulating tiller growth with early mechanical treatments to the crop (rolling, cutting) or chemical applications (foliar urea, CCC and GA). A low seeding rate and early application of foliar CCC at high latitudes, under good moisture conditions prior to heading, promoted 20% more head‐bearing tillers and 6% higher grain yield than standard management practices. However, cultivars differed in their response to CCC. The advantageous effects of CCC at a low seeding rate were attributed to increase, over the controls, in contribution of head‐bearing tillers to grain yield in wheat (cultivar Heta), but more grains per head in oats (cultivar Veli). Varietal recommendations for use of low seeding rate in combination with early CCC spraying should be examined further.
Yield Formation in Mixtures of Rust Resistant and Susceptible Plants of Common Bean (Phaseolus vulgaris L.)
Authors: Panse A. , Davis J. H. C. , Fischbeck G.
Published: April 2008

In a two‐factorial trial, conducted in 1986 at the CIAT farm in Palmira (Colombia), the performance of nine tropical bean lines differing in resistance to rust and seven mixtures obtained by combining these lines on the basis of equal proportions in seed number was evaluated in a rust inoculated treatment and in a fungicide treated control.

Compared to the fungicide treated control, rust attack significantly reduced the yield of all susceptible lines by 24 to 56% in pure stands. In rust inoculated mixtures containing resistant, intermediate and susceptible genotypes, mixture effects on yield increased only by 3.3% compared to the fungicide treated control. In mixtures of common bean a higher proportion of resistant lines appears to be required compared to cereals for comparable reductions in the spread of rust due to lower plant density and correspondingly higher autodeposition rate of uredospores.
Maximizing Sugarcane Yield by Increasing Plant Population Density, Minimizing NO3‐N Leaching and Improving Soil Organic Matter in Different Crop Rotations
Authors: Yadav R. L. , Prasad S. R.
Published: April 2008

In a field experiment conducted during 1992–95 at Lucknow, India, sugarcane was planted in rows 60 and 90 cm apart in three crop rotations (rice‐sugarcane‐ratoon, Sesbania aculeata for green manure‐sugarcane‐ratoon, and cowpea‐sugarcane‐ratoon) with 0, 150 and 300 kg N ha−1 as urea either with or without farmyard manure (FYM) at 10 t ha−1. Sugarcane yields were significantly greater in the Sesbania rotation than in the other because of a larger N uptake. N uptake of the crop was significantly affected by soil organic carbon, and available N and K contents. Ratoon yields, however, were largest in the cowpea sequence followed by the rice rotation, probably due to a prolonged residual effect of cowpea and rice root residues. The residual effect of a Sesbania green manure was negligible as demonstrated by the low NO3‐N content of the soil profile after sugarcane harvest compared to the other two crop sequences. The total cane productivity (main sugarcane plus ratoon) was greater (156 t ha−1) in the cowpea rotation than the Sesbania (152 t ha−1) and rice (140 t ha−1) rotations.
Smut Disease Incidence and Mineral Composition of Corn as Affected by N Fertilizer Sources and K Application Rates
Authors: Kostandi S. F. , Soliman M. F.
Published: April 2008

A 2 year field experiment was initiated to compare the effect of ammonium nitrate (AN) and urea (U) fertilizer sources at 0, 45, 90 and 135 kg N acre−1 in combination with 0 and 48 kg K2O acre−1 on dry matter yield (DM), smut index (SI) and ear leaf nutrient composition. The plants at 8‐leaf growth stage were exposed to artificial infection and the severity was rated on a 1–9 scale. Elemental leaf (N, K, Ca and Mg) and DM were determined at silking and harvest time, respectively. N:(K+Ca+Mg) ratio in plant tissue was calculated. The plants supplied with AN fertilizer appeared to have had greater advantage in DM yield, accompanied by a marked increase in smut severity at higher N rates than U‐treated plants. On average, the relative increases in DM and SI for AN were 8.2 and 9.1%, respectively. Potassium application suppressed smut incidence by 19.6%. The leaf analysis data showed that the plants treated with AN were associated with greater cation uptake than LJ‐fed plants. Increasing N rates enhancedsmut severity and resulted in remarkable increases in DM and ear leaf nutrient composition. Leaf Ca and Mg contents were decreased hy increasing K3O rates. The correlation coefficients (r) between ear leaf nutrient contents and SI showed variable significant effects among N sources. Because the plant nutrient levels are determined by many variables, attention was drawn to N:(K+Ca+Mg) ratio in plant tissue for better smut disease interpretations.
Effects of Tillage and Cropping Systems on Soil Moisture Balance and Pearl Millet Yield
Authors: Saxena Anurag , Singh D. V. , Joshi N. L.
Published: April 2008

A 2‐year study was conducted to determine the effects of tillage and cropping systems on soil moisture balance, growth and yield of pearl millet (Pennisetum glaucum (L.) R.Br.). Three tillage treatments, viz. minimum tillage (one harrowing), conventional tillage (two harrowing, cross) and deep tillage (ploughing followed by two har‐rowings), and four cropping systems, viz. monoculture of pearl millet, pearl miliet‐clusterbean (Cyamopsis tetra‐gonoloba (L.) Taub.) rotation, monoculture of pearl millet with 5 t ha−1 farm yard manure (FYM), and intercropping of pearl millet and clusterbean, were compared. Deep tillage improved the soil moisture storage, water use efficiency and grain yield of pearl millet while consumptive use of water was higher with minimum tillage. Total dry matter yield with deep tillage and conventional tillage was 23.2 and 10.2% higher than minimum tillage in the season 1, and the corresponding values for season 2 were 30.7 and 13.3%. The Pearl millct‐clusterbean rotation and monoculture of pearl millet with the application of 5 t ha−1 FYM gave 17.2 and 6.1% higher yield than monoculture of pearl millet, respectively. Maximum water use efficiency was observed in rotation followed by FYM application.
Plant Nutrient Supply from Nine Agroforestry Tree Species to Wheat (Triticum aestivum) Analysed by Vector Diagnosis
Authors: Anthofer J. , Hanson J. , Jutzi S. C.
Published: April 2008

Six‐week‐old wheat seedlings (Triticum aestivum) grown in pots with an alfisol soil with vertic properties and mulched at a rate equivalent to 10 t ha−1 with leaf prunings of Grevillea robusta, Erythrina abyssinica, Gliricidia sepium, Albizia schimperiana. Acacia nilotica. Acacia polyacantha, Leucaena leucocephala, Leucaena pallida and Entada abyssinica were used to diagnose nutrient contributions by these tree species. A control treatment of 20kg P+ 30kg N ha−1 was chosen as the reference treatment for the vector analysis applied to the mulch effects. Nitrogen was found to be the most important nutrient in seedlings mulched with L. pallida, L. leucocephala, Erythrina abyssinica and to a lesser extent A. schimperiana. Other nutrients of these mulches were also in the deficiency zone but with shorter vectors and therefore with lower impact. Since all these mulches showed increased values for shoot dry weight, nutrient concentration and nutrient uptake they have still reserves for further plant growth and appear therefore to be good mulch sources for annual crops. In contrast, wheat seedlings treated with A. polyacantha and Entada abyssinica had at least some vectors in the toxic zone due to an excess of nutrients while Grevillea treated plants showed a typical toxicity response with large vectors for all nutrients in between the toxic and the antagonistic zone. Allelopathic compounds might also have been involved.
Effects of Stem‐Injected Sucrose on Photosynthesis and Productivity of Water Stressed Corn Plants
Authors: Zhou X. M. , Madrmootoo C. A. , MacKenzie A. F. , Smith D. L.
Published: April 2008

Water stress during silking or early kernel development decreases the number of kernels set by corn (Zea mays L.) plants. Previous work has suggested that lack of assimilate supply due to water stress at silking was a major factor in the resulting reproductive failure. A greenhouse experiment was conducted to test the hypothesis that sucrose supplementation of water stressed corn plants can prevent decreased kernel set. Sucrose was injected into corn stems at three concentrations [0 (distilled water), 150 and 300 g L−1] for 30 days starting at silking. Water availability was controlled by either maintaining a water table at 50 cm from the soil surface (well watered) or by withholding water starting one week before silking (water stress) until the fifth day after silking. The photosynthesis rate of water stressed plants was 25% that of well‐water plants on the first day of silking. On average, the daily injection rate for distilled water was 1 mL higher than that of the sucrose treatments over a 30 day injection period. No difference in daily uptake rate was observed between the 150 and 300 g sucrose L−1 treatments. Over water availability treatments approximately 17 g sucrose were injected into corn plants during the 30 day injection period. Corn plants receiving sufficient water supply produced bigger ears, with more seeds and greater 100‐seed weight values, leading to higher total plant dry matter accumulation than water stressed plants. Injection of 300 g sucrose L−1 increased the weight of the injected internodes by 28%, compared with distilled water injection. The highest grain yield was for the plants injected with 150 g sucrose L−1, but only under sufficient water supply. The plants injected with 300 g sucrose L−1 produced the least grain regardless of moisture availability. Thus, the exogenous sucrose supplementation influenced kernel set only under conditions of sufficient soil water supply. These results indicate that plant reproductive development after silking was limited more by water availability than assimilate supply, suggesting that some overall plant response to water stress, perhaps mediated by hormonal signalling, was more important than carbohydrate supply. These results indicated that plant desiccation occurred during floral development or pollination; irreversible loss of florets on unsuccessful pollination could result, thus, grain yield would be limited more by sink size than by availability of photosynthate.
Some Agronomic and Physiological Aspects of Salt Tolerance in Cotton (Gossypium hirsutum L.)
Authors: Qadir M. , Shams M.
Published: April 2008

Evaluation of commonly grown cotton (Gossypium hir‐sutum L.) genotypes under saline environment may help to cope with the venture of the crop failure in salt‐affected soils. In a pot experiment, four cotton genotypes (MNH‐93, NIAB‐78. S‐12, and B‐557) were grown to compare their relative performance on a sandy clay loam soil (original ECe = 1.9 dS m−1) salinized with a salt mixture (Na2SO4, NaCl, CaCl2, MgSO4 in the ratio of 9:5:5:1 on equivalent basis) to EQ levels of 10 and 20 dS m−1. The crop was raised to the flower initiation stage. The imposed salinity stress exhibited deleterious effect on the germination and vegetative growth with significant differences among the genotypes. Leaf area, stem thickness, shoot (stem + leaves) and root weights decreased with the increase in substrate salinity. NIAB‐78 showed the least decline followed by MNH‐93. Leaf thickness showed an opposite trend as an increase in this parameter was observed with the rising salinity, the maximum increase being in the case of NIAB‐78. Analysis of the leaf sap showed increased Na+ and Cl− concentrations and decreased K+ concentration with the increase in substrate salinity. A better osmotic adjustment, a lower Na+/K+ ratio and a lower Cl concentration were found in the leaves of NIAB‐78 followed by MNH‐93. This contributed towards their better growth performance under saline conditions.
Sulphur and Micronutrient Nutrition of Groundnut in a Calcareous Soil
Authors: Singh A. L. , Chaudhari V.
Published: April 2008

Field experiments conducted on a calcareous soil have shown that application of elemental sulphur reduced the chlorosis of groundnut leaves and increased the dry matter, nodule biomass, pod, haulms, and oil yields, and concentration of nutrients in leaf tissue and their uptake by groundnut. The application of iron (Fe), zinc (Zn) and manganese (Mn) further helped in recovering the chlorosis of groundnut and increased the above parameters. On average, application of 20 kg S ha−1 as elemental sulphur (S) increased pod yield by 8.6–9.8% and oil yield by 8.8–15%. However, application of 10, 2, and 4 kg ha−1 of Fe, Zn and Mn, increased pods by 19.5, 13.6, and 11.7% and oil yield by 20.1, 13.9 and 12.2%, respectively.
Effect of Relative Sowing Time on the Growth and Yield of the Component Crops in Okra/Maize and Okra/Cowpea Intercropping Systems
Authors: Muoneke C. O. , Asiegbu J. E. , Udeogalanya A. C. C.
Published: April 2008

The effects of variations in the relative sowing time of component crops in okra/maize and okra/cowpea intercropping systems were examined in 1990 and 1991 cropping seasons. Okra was either sown the same day as, or two weeks before or after maize or cowpea. Intercropping reduced the growth and yield of okra, maize and cowpea relative to their sole crops. However, okra yield was depressed more by maize than by cowpea, especially when okra was sown two weeks after maize. Comparative assessment of okra/maize and okra/cowpea mixtures suggests that it is better to grow okra and cowpea together than intercropping okra and maize because yield advantages were always higher in okra/cowpea (67% and 59% in 1990 and 1991 respectively) than in okra/maize (15% and 29%). The results were discussed in light of competitive abilities of the various components in the mixtures.
Yield Stability in Long‐term Released Maize Hybrids FAO 100 and 200
Authors: Rozman L. , Vasilj Đ. , Kozumplik V.
Published: April 2008

The purpose of this study was to assess changes in yield stability of tnaize hybrids during a 20‐year period and to relate them to yield changes. The data on FAO 100 and FAO 200 hybrids, released by the former Yugoslav Committee for Releasing Varieties, were utilized. Most ofthe released hybrids fell into the first and the second stability group (Francis and Kannenberg 1978). The bi values (Finlay and Wilkinson 1963) of the released hybrids, except two from FAO 100 and four from FAO 200 group, did not differ significantly from 1.0. Also, all but one from FAO 100 and one from FAO 200 released hybrids did not differ in aj value (Shukla 1972) significantly from 0. Values of A, and aj stability parameters changed only slightly during the 20‐year period. During the same time the yield ofthe FAO 100 hybrids did not change. In the FAO 200 group the yield increased, but the genetic gain was not significant. The stability parameters were not in a significant correlation with the yield.
Effect of Okra Planting Density and Spatial Arrangement in Intercrop with Maize on the Growth and Yield of the Component Species
Authors: Muoneke C. O. , Asiegbu J. E.
Published: April 2008

The effects of three okra planting densities (28 000; 56 000 and 111 000 plants ha1) intercropped within or between maize rows were investigated in two field trials during the 1990 and 1991 wet seasons at Nsukka. The plant height and the leaf area index (LAI) increased as the planting density increased in sole or intercropped okra while the number of branches per plant decreased with increasing okra planting density. The height of maize plants also increased as okra planting density increased but the LAI decreased. Intercropping reduced the yield and yield components (number and weight of pods per plant) of okra and maize (number of cobs, cob length and 100‐grain weight). Increasing okra planting density reduced the sole and the intercropped okra and also the maize intercrop yield by reducing the number of pods and grains as well as the pod and grain size, respectively. Assessment of the productivity ofthe mixtures showed that the highest yield advantage (35%) of growing okra and maize together was obtained at 28000 okra plants ha1 while the highest monetary return was realized at the highest okra planting density of 111000 plants ha1 intercropped between maize rows. The patterns of row arrangement did not have effect on the growth, yield and yield components of the mixtures.
Conservation of Spring Cut Italian Ryegrass as Round Bale Silage: Effect of Stage of Maturity on Ensiling Characteristics and Forage Nutritive Value
Authors: Andrighetto I. , Berzaghi P. , Cozzi G. , Gottardo F. , Zancan M.
Published: April 2008

Spring cut Italian ryegrass was harvested at two different stages of maturity: lake vegetative (EARLY) and flowering (LATE). The wilted forage was round baled and then ensiled by wrapping in plastic film. EARLY harvest reduced dry matter (DM) yield significantly as compared to LATE (5.6 vs. 10.5 t ha−1; P < 0.01). However, forage quality both before and after ensiling was better for EARLY with higher crude protein (CP) and non‐structural carbohydrates content and a lower amount of cell walls (NDF). Higher pH and the fermentation characteristics confirmed the poor quality of LATE silage, having higher content of butyrate, propionate and acid detergent insoluble nitrogen and a lower concentration of lactic acid.

Dry matter intake of EARLY silage by sheep (average 65.0 ± 7.3 kg LW) fed solely forage ad libitum was 37 % higher than LATE (1386 vs. 1011 g DM day−1; P < 0.05) due to its better palatability and digestibility. In vivo DM digestibility of EARLY silage was 76.1 % while it decreased to 58.2 % for LATE silage. Estimated metabolizable energy content of EARLY silage (11.5 MJ kg−1 DM) was 29 % higher than LATE (8.9 MJ kg−1 DM) resulting as similar to the reference value of a high quality perennial ryegrass silage. The forage conservation system of ensiled round bales is effective and recommended when spring cut Italian ryegrass is harvested at an early stage of maturity.