bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Seeding Rate on Growth Duration and Accumulation and Partitioning of Dry matter in Oats
Authors: Peltonen‐Sainio P. , Järvinen P.
Published: April 2008

Crop management influences considerably the three components of grain yield, growth duration, growth rate, and harvest index (HI). Effects of seeding rate on these yield components in oats (Avena sativa L.) was assessed in field experiments at the Viikki Experimental Farm, University of Helsinki, Finland (60°13′N) in 1991 and 1992. Three Finnish oat genotypes were evaluated; a long‐strawed landrace cultivar, a moderately long‐strawed modern cultivar, and a semi‐dwarf breeding line. The following traits were measured: grain yield, days from sowing to yellow ripeness, number of tillers on main shoot, phytomass, vegetative phytomass, and their growth rates (PGR and VGR, respectively), panicle weight and its filling rate (PFR), HI, leaf area index (LAI), and at intervals, dry‐matter accumulation in leaves and straw.

Increases in seeding rate significantly decreased growth duration and PGR of individual plants but increased PGR on a ground area basis. Seeding rate did not, however, affect HI. When seeding rate was increased from 200 seeds m−2 to 500 seeds m−2, reductions in vegetative phytomass, panicle weight, VGR, and PFR for individual plants ranged between 20 and 40 %, depending on genotype. At ≥600 seeds m−2 differences in these components between seeding rates were modest. However, PGR, VGR, and PFR per unit ground area increased with increasing seeding rates up to 600–700 seeds m−2. Moreover, the higher the seeding rate, the higher the peak LAI (2.7 maximum) and the earlier the canopy closure. Hence, our results showed that a seeding rate of 600–700 seeds m−2, which resulted in uniculm growth habit, is advantageous in terms of grain yield at high latitudes due to higher biomass accumulation and subsequently greater interception of PAR.
Ertragsbildung von getreidereichen Fruchtfolgen und Getreide‐monokulturen in einem extensiven und intensiven Anbausystem
Authors: Panse A. , Maidl F. X. , Dennert J. , Brunner H. , Fischbeck G.
Published: April 2008

Yield formation in cereal‐rich crop rotations and monocultures in an extensive and intensive crop‐management system

In a long duration trial, conducted from 1979/80 to 1992 at TU‐Munich's research station in Roggenstein, the performance of monocultures of winter wheat, winter barley and winter rye, as well as numerous cereal‐crop rotations were compared in an extensive and intensive crop‐management system. The results obtained can be summarized as follows.

Over the course of 13 years, the influence of the immediately preceding crop on the yield of the main crops was of much greater significance than the rotation as a whole. With winter wheat, no yield differences could be observed between monoculture and cereal crop rotation (if the rotation did not include oats). Oats, rape, field bean, pea, potato and maize as preceding crops, however, in crop management systems, led to, on average, an increase in yield of 13 dt/ha from the following wheat. Winter barley yields were not significantly different in monoculture, cereal crop rotations and crop rotations containing 66% cereals. Furthermore, winter rye yields were the same in monocultures and cereal crop rotations. With all cereals, intensification of fertilizing and chemical plant protection led to a considerable increase in yield, but did not diminish the effects of the preceding crop. Hence, even with the use of modern agronomical techniques it is impossible to compensate for yield losses due to crop rotation.
Comparison of Vernalization Requirements and Frost Resistance of Winter Rape Lines Derived from Double Haploids
Authors: Markowski A. , Rapacz M.
Published: April 2008

Vernalization requirements and cold resistance of 13 lines of winter rape derived from doubled haploids obtained by androgenesis were investigated. The degree of vernalization requirements was examined in two parallel experiments. In the first experiment seedlings aged 2 weeks were vernalized during 63 and 35 days under controlled conditions, at 5 °C. In the second experiment the natural conditions of vernalization were differentiated by sowing the plants at four different dates in spring: March 15th, April 15th, May 15th, and at the latest date excluding vernalization, June 5th. The lines examined revealed differentiation of vernalization requirements that were similar in both experiments; all the lines required a period of exposure to cold before flowering. Cold resistance of lines was estimated in two successive series at −15 °C and −17 °C. Before testing the plants were kept in natural field conditions from the beginning of September until the middle of November. Testing of cold resistance was preceded by hardening under controlled conditions. Considerable differences in cold resistance was found in the forms investigated.

The results obtained do not show any relation between frost resistance and the degree of vernalization requirements, as the line characterized by the strongest winter habit of growth showed low cold resistance, whereas the lines which were closer to spring growth habit showed the highest level of cold resistance; the lines with the least vernalization requirements revealed the highest level of cold resistance. This conclusion can be confirmed by the significance of the correlation coefficients between the various indices defining the frost resistance and the indices of vernalization requirements.
Correlation Studies and Path Coefficient Analysis in Sesame (Sesamum indicum L.)
Authors: Subramanian Selvi , Subramanian M.
Published: April 2008

Field investigations were carried out at the Agricultural College and Research Institute, Madurai, India during 1989—1990 to study the genotypic character association in sesame. The F4 and F5 generations of TSS6 X TMV3 and TMV3 X TSS6 were raised and eight genotypic characters were recorded: plant height; primary branches; secondary branches; capsule number per plant; seed number per capsule; 1000 seed—weight; oil content and seed yield per plant. Correlation studies showed that the magnitude and direction of correlation between eight pairs of traits varied with generations in both crosses involving two genotypes reciprocally. Single plant yield had a strong significant and positive relationship with capsule number in both generations of the two cross combinations indicating the close link between the two traits. The path coefficient analysis revealed that direct and indirect contributions by different traits primary branches, secondary branches, capsule number per plant, seed number per capsule and 1000—seed weight had to be considered as the most important traits in the determination of seed yield and selection of parents.
Phosphorus Accumulation and Translocation in Wheat as Affected by Cultivar and Nitrogen Fertilization
Authors: Papakosta Despo K.
Published: April 2008

To improve nutrient management strategies in wheat more information is needed about the interaction effects among nutrients in their uptake and redistribution in the plants, in relation to different genotypes. Therefore, two bread (T. aestivum L.) and two durum (T. durum Desf.) winter wheat cultivars were grown in the field for 2 years (1986, 1987) in a silty‐clay soil under different nitrogen (N) levels, in Northern Greece. Nitrogen at a rate of 150 kg ha−1 was applied before planting or 100 kg ha−1 before planting and then 50 kg ha−1 at early boot stage. Cultivar differences in phosphorus (p) concentration were observed only in vegetative parts but not in the grain. Maximum p accumulation was observed either at anthesis or at maturity. During grain filling dry matter and p accumulation in the grain followed almost the same pattern. Phosphorus translocation efficiency of the cultivars at the 2 years ranged from 70.7 to 84.3 % and the amount of p in the grain derived from translocation 52 to 100 %. Phosphorus translocation efficiency was weakly correlated with p content in grain only in 1986, while phosphorus harvest index (PHI) was positively correlated with harvest indst (HI) both years (r = 0.82** in 1986 and 0.75** in 1987). Nitrogen application mainly affected p accumulation of the cultivars via its effect on biomass production. The split N application promoted slightly the p uptake in 1987 and this resulted in the reduction of both the contribution of the translocated p to the grain and the efficiency of p utilization for total biomass. Results indicated that p accumulation and translocation and the efficiency of p utilization in wheat were mainly determined by the genotype in relation to environmental condition of growth.
Nitrogen Fixation, Growth and Yield of Intercropped Mungbean (yigna radiataL.) and Groundnut (Aracbis bypogaeaL.) as Affected by the Genotype
Authors: Senaratne R. , Gunasekera M. T. K.
Published: April 2008

15N‐aided investigations were conducted to ascertain the Nj fixation and the nitrogen (N) contribution by mungbean (Vigna radiataL.) and groundnut (Aracbis hypogaeaL.) when intercropped with maize (Zea mays). The study involved growing seven genotypes of the above legumes with maize in alternate rows in two separate experiments. A sole crop of maize was used as the reference crop to determine N2 fixation by the15N methodology. Significant genotypic differences in pod yield and stover N content were observed in intercropped mungbean and groundnut. The percentage N derived from the atmosphere showed a genotypic variation of 31 to 45 % (7 to 10 kg N2fixed ha−1O in mungbean and 47 to 69 % (9 to 18 kg N2fixed ha−1) in groundnut. Harvest index for N varied from 58 to 77 % in mungbean and 55 to 75 % in groundnut. In groundnut, the uptake of soil N was significantly affected by the genotype. Assuming that the N contribution to the soil by the helow‐ground plant parts was negligible, the removal of seeds at maturity resulted in a negative N balance in the soil in all the genotypes of mungbean. In groundnut, some genotypes produced a positive N balance in the soil. Owing to high N2fixation capacity and low harvest index for N, groundnut showed a greater N supplementing ability than mungbean.
Significance of Seed Source on Grain Yield in Faba Beans (Vida faba L.) and Dry Peas (Pisum sativum L.)
Authors: Stelling D. , Malau S. , Ebmeyer E.
Published: April 2008

In order to investigate the significance of seed source on yield and related characters 47 seed lots of seven faba bean varieties and 24 seed lots of five dry pea varieties were tested in three series of field trials. The grain yield of the faba bean varieties tested was considerably modified by seed source, whereas only small and nonsignificant effects of seed source were found in dry peas. In general, seed sources with a high thousand grain weight, a high protein content, high portions of undamaged and healthy seeds, and in faba beans a high degree of cross‐fertilization exhibited superior grain yields. Production of high‐performance seed proved to be the most difficult for the large‐seeded and white‐flowered faba bean varieties. Based on a tabular summary on factors affecting effects of seed source problems of seed production in both grain legumes and their impact on yield are discussed.
Agronomic Variability in Selected Triticum turgidum x T. tauschii Synthetic Hexaploid Wheats
Authors: Villareal R. L. , Mujeeb‐Kazi A. , Toro E. Del , Crossa J. , Rajaram S.
Published: April 2008

Two trials were conducted at the Mexican National Institute of Agricultural Research Experiment Station at Yaqui Valley, Sonora, Mexico to investigate the nature and extent of agronomic variation in 50 synthetic hexaploid (SH) wheats (2n = 6x = 42, AABBDD) derived from Triticum turgidum (2n = 4x = 28. AABB) ×T. tauschii (In = 2x = 14, DD) crosses for subsequent use in wheat improvement. Plant height, spike length, days to flowering, physiological maturity, grain yield, above‐ground biomass at maturity, harvest index, yield components and test weight were determined.

Significant agronomic variation was observed among the germplasm evaluated. Outstanding SH genotypes were identified with higher grain yield, above‐ground biomass at maturity, 1000‐grain weight, and spikes m−2 than the bread wheat (Triticum aestivum L.) check cultivar Seri 82. Genotypic correlations of grain yield with other character traits show that grain m2 was the most important determinant of gram yield (r = 0.993). Data on agronomic traits subjected to complete linkage cluster analysis resulted in classifying the genotypes into two distinct phenotypic groups excluding Seri 82. Groups generally corresponded to durum progenitors of the SH with significant group differences for all characters. This demonstrates use of practical numerical analysis procedures to describe agronomic variation in representative SH genotypes. Clustering by quantitativy traits may be valuable for identification of genotypes with divergent sources for breeding and agronomic purposes.
Körner‐Amarant (Amaranthus ssp.): Anbau, Züchtung und Werteigenschaften einer alten Indio‐Pflanze
Authors: Wegerle N. , Zeller F. J.
Published: April 2008

Grain amaranth (Amarantbus ssp.): Cultivation, Breeding and Properties of an Old Indian Plant

Current knowledge on evolution, systematics and biology, as well as on the status of genetic and breeding efforts on the grain‐amaranth species A. caudatus, A. cruentus and A, hypochondriacus are compiled. The mineral contents and nutrient composition are compared with those of wheat and maize, and the potential cultivation of these crops in Central Europe, on the basis of experimental trials, is discussed. Amaranth could become a valuable human food source in Europe
Prolonging Seed Viability in Groundnut (Arachis hypogaea L.) with Calcium Chloride
Authors: Padmanabhan G. , Nagarajan M. , Manian K. , Annamalainathan K.
Published: April 2008

Groundnut pods stored in gunny bags, polythene lined gunny bags, polythene lined gunny bags with fused CaCl2, mud pots, and bamboo baskets showed significant differences in germination and vigour. The increased viability of pods in polythene lined gunny bag with fused CaCl2 is attributed to low moisture content and high dehydrogenase activity. The present study showed that the viability of groundnut pods could be enhanced using desiccant like fused Calcium Chloride.
Response of Black Nightshade (Solanum nigrum L.) to Nitrogen Application
Authors: Khan M. M. A. , Samiullah  , Afaq S. H. , Afridi R. M.
Published: April 2008

A pot experiment was conducted on Black nightshade (Solanum nigrum L.) to study the effect of urea nitrogen and select the optimum dose required for its vegetative and reproductive growth, leaf NPK content, yield of fruit and fruit solasodine. Urea was applied at 0.0, 0.45, 0.90, 1.35, 1.80 and 2.25 g N per pot which contained 3.5 kg soil. Seeds were sown directly in pots and plant samples were drawn at fortnightly intervals for recording growth and yield parameters. In addition, solasodine content in fruit and N, P and K in leaves were also estimated. The results showed that all the parameters were influenced by N. In general, N at 1.80 g per pot was optimal.
Effect of Shading on Nodule Growth and Sugar Distrihution in Faha Bean (Vicia Faba L.)
Authors: XiA M. Z.
Published: April 2008

The faba bean (Vicia faba L.) is an important grain legume world wide, yet the relationship between light intensity and nodule development and N2 fixation has received minimal attention. An experiment was conducted to study the effects of shading on faba bean growth, seed yield, nodule development, and the distribution of total N and total sugar among plant parts. Seeds of the V. faba cultivar Xichang Dabai were sown in pots at Xichang. China, in 1986–90. The plants subjected to 50 % and 20 % shading for 145 d had thinner and taller main stem than the control, and fewer flowers, pods, and seeds. Poor dry weight of organs and less developed underground parts were recognized. Shading caused the deficiency of photosynthate (supply), subsequently less nodules formed poorer fresh weight of nodules was produced and nodule senescing advanced. Total N and total sugar contents per plant and in roots, stems and leaves were consistently lower under shading regimes, but the contents in nodules did not change significantly. It seems that the insufficient photosynthate supply limited both N and C metabolism in shading plants by first limiting growth of the whole plant and nodule, and that the lower total N content in faba bean plant under shading regime was attributed to an decreased effective nodule mass and advanced nodule senescing.
Vergleichende Feldversuche mit Land‐ und Zuchtsorten von Durumweizen (Triticum turgidum var. durum) unter verschiedenen ökologischen Bedingungen im Mittelmeerraum
Authors: Kyzeridis N. , Biesantz A. , Limberg P.
Published: April 2008

Comparative trials with durum‐wheat landraces and cultivars in different ecological environments in the mediterranean region

Durum‐wheat landraces (local varieties) and cultivars (released varieties) were examined for grain yield and some qualitative traits in three environments in 1985 and 1986. The purpose of this research was the preservation of the local genetic material and its use in durum‐wheat breeding programmes in mediterranean countries. It was confirmed that, during the graining period (heading to yellow ripeness), the landraces were more resistant to drought and high temperatures than the cultivars. A short graining period led to a sharp rise in the percentage of protein. On the other hand, the protein content decreased when the grain yield increased. Contrary to the cultivars, the vitrousness of some landraces was not negatively influenced by high soil moisture during the graining period. These landraces combined high grain yield with a high percentage of vitrous kernels and can be considered as valuable gene material for breeding purposes.
Transpiration Dynamics in Cadmium‐Treated Soybean (Glycine max L.) Plants
Authors: Leita L. , Marchiol L. , Martin M. , Peressotti A. , Vedove G. Delle , Zerbi G.
Published: April 2008

Soybean (Glycine max L.) plants, cv Richland, were grown during 30 days in a nutrient solution. After this period the plants were treated with a 50 μM Cd(NO3)2 solution. Sap flow rate and stomatal conductance were monitored during 4 consecutive days; at the end of this period relative water content and stomatal width and length were determined on fully expanded leaves. On the second day from the Cd treatment sap, flow rate and stomatal conductance in the treated plants were reduced to 60% of the control plants. Stomatal conductance kept on decreasing up to the fourth day. Cadmium decreased the leaf relative water content and the reduction in the stomatal closure was supported by an increase in the L/W ratio of the stomata. Root water uptake should be the primary mechanism reduced by Cd stress in soybean, and this reduction is consistent with the decrease in transpiration rate and with the stomatal closure.
Effect of Irrigation, Mulch and Nitrogen on Yield and Composition of Japanese Mint (Mentha arvensis L. subsp. haplocalyx var. piperascens) Oil
Authors: SAXENA ANURAG , SINGH J. N.
Published: April 2008

Effects of irrigation, mulch and nitrogen on yield and composition of Japanese mini (Mentha arvensis L. subsp. haplocalyx Briq. var piperascens) oil were studied using a replicated experiment. Two harvests were obtained 120 davs atter planting and 75 davs after the first harvest. Significantly higher drv matter and essential oil yields were obtained with frequent irrigations (50 mm Cumulative Pan Evaporation), application of mulch and Nitrogen. The economic optimum rate of N was 215 Kg ha‐1. The essential oil from the first harvest was richer in menthol (78.8%) than the oil obtained from second harvest (75.2%). Soil moisture extraction was maximum between 15 and 30 cm soil depths. Consumptive use, water use efficiency and moisture use rate‐were maximum under higher irrigation levels and mulch application which reflect that more availability of moisture in soil profile with frequent irrigations and application of mulch.
Regulation of Correlative Senescence in Arachis hypogaea L. by Source‐Sink Alteration through Physical and Hormonal Means
Authors: Ghosh A. K. , Biswas A. K.
Published: April 2008

Amongst the plants (Arachis hypogaea) subjected to differential reproductive manipulations, the leaf levels of chlorophyll and sugar and the dry weight of the aerial plants increased more (except sugar level in defruited plant) in the deflorated plants than either in the defruited or control plants, and the order of senescence was: control > defruited > deflorated. Seed yield per plant increased in deflorated plants as a result of increase in the number of pods (sink size) and reduction in the sink strength (seed wt per pod). While 75 % defoliation caused a decrease in all the parameters relating to senescence (chlorophyll, protein, reduced nitrogen, sugar and dry wt), 25% defoliation caused a slight decrease of chlorophyll level of leaf and aerial plant weight. However, the level of protein and reduced nitrogen in the leaf and sugar in the stem increased by the latter (through 25% defoliation). Defoliation up to 25% reduced seed yield by only 2%. Whereas the level of chlorophyll and aerial plant dry weight were not significantly changed by either kinetin or ABA, the level of protein and reduced nitrogen in the leaf and sugar level in both leaf and stem increased by kinetin. GA3 increased almost all the parameters studied. All the three phytohormones increased the yield, mainly by increasing the sink size rather than the sink strength. It is concluded that the aerial flowers are more lethal than the underground fruits in inducing whole plant senescence where the leaf senescence is uncoupled from fruit maturation in normal condition possibly due to sink limitation.
The First Step Towards a Decision‐support System for Sugar‐beet Growing: Selection of a Basic Growth Model
Authors: Smit A. B. , Struik P. C.
Published: April 2008

Four simulation models were tested for their suitability as a basic growth model in a decision support system for sugar beet growing in The Netherlands. SUCROS and SUBEMO are complex, mechanistic models; LINTUL and PIEteR are relatively simple regression models including causal relationships at a higher level of integration. All four models are dynamic, i.e. they calculate daily development and production rates.

The selected model had to be able to predict root and sugar yields accurately and to correct for suboptimal water contents of the soil. It should be possible to include location‐specific data and new modules, e.g. for nitrogen fertilization or plant density. Finally, the farmer should be able to collect the required input data easily and cheaply.

The tests showed that PIEteR predicted root and sugar yields best, partly because it contained water‐balance corrections, based on location‐specific soil characteristics. PIEteR could not be applied universally because of its regression character at a high level of integration, but it met the requirements specified.
Tall and Hard Fescue Responses to Periodic Soil Water Deficits
Authors: Brar G. S. , Palazzo A. J.
Published: April 2008

Tall (Festuca arundmacea Schreb.) and hard (Festuca ovina var. longifolia (L.) Koch) fescues are widely sown to stabilize disturbed soils in the cool–humid and transition climatic zones of the USA. Our objectives were to: a) quantify changes in the allocation of dry matter and growth of tall and hard fescue, forced to grow on stored soil water in sandy soil; and b) compare dry matter allocation over time between roots and shoots to evaluate the dynamics of root‐associated drought avoidance mechanisms. A randomized complete block experiment with four replications and two factors (species and stress level) was conducted in a greenhouse. The main blocks consisted of two fescue species: tall fescue and hard fescue; sub‐blocks contained stress levels: well‐watered and stressed. Low, medium and severe stresses were imposed by withholding water in one set of pots. The types of fescue species grown significantly affected leaf area (LA), plant height (PH), water use (WU), root length (RL), longest root (LR), root area (RA), shoot (SDB) and root dry biomass (RDB), and root:shoot ratio (R/S). Stress level affected PH, WU, LR and RL at low stress; WU, LR and RA at medium stress; LA, PH, SDB, WU, RL, LR, RA and R/S at severe stress. Tall fescue had greater LA, PH, WU, RA, RL, LR, SDB, RDB and R/S than hard fescue under all treatments. Stress reduced LA, PH, SDB, WU, RA, RL, LR and R/S. Significant correlations were obtained for LA with RL, WU, LR, PH. RA, SDB, RDB; RL with WU, LR, PH. RA, SDB. RDB; WU with LR, PH, RA, SDB, RDB; LR with PH. RA, SDB, RDB; PH with RA, SDB, RDB; RA with SDB, RDB; and SDB with RDB. In conclusion, hard fescue had a shallower root system, shorter plant canopy, slower growth, and transpired less water to make it more drought tolerant. Tall fescue, with a deeper root system, longer plant canopy, faster growth, and greater water transpiration, is less drought tolerant at medium and severe stresses. Root attributes strongly correlated with shoot attributes and can be considered for breeding programs promoting drought tolerance.
Evaluation of the Heterosis on Leaf Photosynthesis of Remote‐Cross F1 Rice (Oryza saliva L.)
Authors: Hirao K. , Kubota F. , Agata W.
Published: April 2008

The heterosis of leaf photosynthesis was studied on the main characters included in the range from CO2exchange rate (CER) to enzymatic activity using a remote cross F, rice. The CER was significantly higher than those of the parental strains, showing a 111 % heterosis effect on average; at the same time strong heterosis was observed for the leaf area production and growth. Also stomatal and mesophyll conductances increased in the F1 rice, which may contribute to the increase in CER. Chlorophyll content (Ch1), soluble protein content (SPC) and ribulose 1,5‐bisphosphate (RuBP) carboxylase activity (RCA) were measured as the internal factors related to photosynthesis, and compared between the F1, rice and the parents. For all these factors, the F1 rice showed low values compared to the parents. Positive heterosis was not expressed here. On the other hand, the specific activity of RCA (RCA/SPC) increased in the F1, rice, showing a 120% heterosis effect. This may be regarded as one of the main causes for the increase in CER of the F1, rice. High CER expressed as heterosis concurrently with large leaf area production is one of the important findings in our study, and this may suggest a high possibility of further improvement in biomass production or yield of rice by gathering the advantageous elements into a hybrid plant.
Timing of Nitrogen Application to Enhance Corn (Zea mays, L.) Yields in a Desert Climate
Authors: Esechie H. A. , Elias S. , Magpantay J.
Published: April 2008

Experiments were conducted in two consecutive years to investigate the response of two corn (Zea mays, L.) cultivars, Eperon and Challenger, to timing of N fertilizer in a desert climate. Fertilizer was applied three times (at planting, 6 weeks after sowing (6WAS) and at 9WAS) to give a seasonal total of 180 kg N ha‐1 The N treatments were Nooo (control), NLOH (60 kg N ha‐1 at planting, none at 6WAS and 120 kg N ha‐1 at 9WAS), NLLL (60 kg N ha‐1 at sowing, 6WAS and at 9WAS) and NLOH, (60 kgN ha‐1 at planting, 120 kg N ha‐1 at 6WAS and none at 9WAS). Generally, N ha‐1 was associated with the highest grain and dry matter yields. Plants in N treated plots had significantly larger number of leaves and ear leaf N contents than the control at mid‐silk. High ear leaf N was associated with high leaf area index and dry matter yield. Based on these results, it would appear that the application of 60 kg N ha‐1 at planting, followed by 120 kg N ha at 6WAS (NLHO) is the most suitable for enhancing corn yields in the desert climate.
Studies on Iron Chlorosis of Sugar Cane (Saccharum officinarum L.) at Metahara, Ethiopia: Soil and Plant Characterisation and Efficiency of Different Iron Sources
Authors: Dametie A. , Mamo T. , Zelleke A.
Published: April 2008

In order to understand the nature and causes of chlorosis at Metahara Sugar Estate (8°53′N and 39°52′E) in Ethiopia, soil profile samples were collected from a ratoon field that exhibited chlorosis. From the same site, the first ratoon sugar cane leaf blades (+ 3) were sampled on the basis of the degree of chlorosis, and thus categorised into green, medium green, medium yellow and yellow. Soil sample analysis indicated that DTPA‐extractable Fe, Mn and Cu were adequate for normal plant growth in spite of an increase in CaCO3 content. Moreover, the chlorotic leaves contained higher iron content than the green ones. Consequently, it is concluded that iron chlorosis of sugar cane at Metahara could be due to physiological inactivation of iron in soils and the plant.

A field experiment was also conducted using sugar cane variety CO‐449 in order to select the most effective iron source to control iron chlorosis of the plant. The plots received the treatments of FeSO4, EDDHA and DTPA at three different levels each as foliar sprays. The untreated plots were used as control. The chemicals were applied on the first ratoon 3 weeks after harvest, and repeated a week after the first spray. Twenty millable canes from the middle two rows were sampled at 12 months for yield and juice quality determinations. Iron sulphate spray at 15 kg ha‐1 increased cane length and commercial cane sugar by 33 and 44 % over the control, respectively. The highest cane yield was secured by spraying DTPA at 1.80 kg ha‐1 even though its recoverable sugar percentage was low. Not all sources of iron improved juice quality.

Since FeSO4 at 15 kg ha‐1 was equally effective as the 30 kg ha‐1 FeSO4, applications, the need to consider other than the currently used rate in the Estate is timely and is very important.
Zum Einfluβ interspezifischer Konkurrenz in einer Kleegrasmischung auf die Futterqualität
Authors: von Boberfeld W. Opitz , Biskupek B.
Published: April 2008

The Influence of Interspecific Competition in a Grass‐clover Mixture on Nutritional Value

In a field experiment, the influence of interspecific competition on the nutritional value of different species in a grass‐clover mixture was studied. The species were Trifolium pratense and Dactylis glomerata or Lolittm multiflorum, respectively. N‐fertilization was varied in two steps (20 and 70 kg N ha‐1 cut‐1). The swards were cut four times a year, and each species was harvested separately. The content of net energy (NEL), crude protein (CP), water‐soluble carbohydrates (WSC) and minerals in each species were determined. The NEL content of the species was only slightly influenced by mixed cropping. The CP concent of the grasses was higher in mixtures with Trifolium pratense than in monocultures. The WSC content of the grasses decreased with an increasing ratio of Trifolium pratense in the mixtures. This was due to a higher N‐supply in the grasses in mixtures compared with monocultures on the one hand, and shading by Trifolium pratense on the other. In a few cases, the WSC content of Trifolium pratense was reduced by mixed cropping with the grasses. The mineral content of three species was clearly influenced by interspecific competition. The extent and the direction of the changes were different in the particular cuts and depended on the growing conditions and yield ratios of the species in the different mixtures. The results show that interspecific competition has an influence on the nutritional value of the species in a grass‐clover mixture.
Amelioration of Drought‐Induced Transplanting Shock in Rice by an Abscisic Acid Analog in Combination with the Growth Retardant Tetcyclacis
Authors: Flores‐Nimedez A. A. , Dörffling K. , Vergara B. S.
Published: April 2008

The protective effect of a synthetic terpenoid analog of abscisic acid (ABA), coded LAB 173711, on transplant shock in rice was investigated under field conditions. Rice seedlings (Fujisaka 5 and IR 20) were taken from a seed bed and their roots were immersed in aqueous solutions of the growth regulators for 24 h. Afterwards they were drought‐stressed for 3 or 6 h by exposing them to direct sunlight before they were transplanted to the field. A pretreatment with either LAB 173711 alone or in combination with the growth retardant tetcyclacis reduced the loss of water during the exposure to sunlight, increased the percentage of survival of the seedlings in the field, and increased the percentage of grain filling of the plants which had survived. The combined application of growth regulators was most effective and may be useful for minimizing transplant shock in rice and other crops.
Influence of Variable Amounts of Irrigation Water and Nitrogen Fertilizer on Growth, Yield and Water Use of Grain Sorghum
Authors: Khanna‐Chopra R. , Kumari S.
Published: April 2008

Sorghum hybrid CSH‐6 was grown in fields in Delhi, India between July–November 1986 in order to study the effect of nitrogen nutrition and irrigation on dry matter accumulation, grain yield and water use. The treatments included 40 Kg Nha−1 combined with two irrigations (30 DAS, 60 DAS), one irrigation (60 DAS) and no irrigation respectively. Rainfall during the crop season was only 17 cm. The unirrigated plants were considerably water stressed and exhibited very low leaf water potential, less leaf area, delayed anthesis, longer crop duration but shorter grain filling duration. The ears showed sterility and yield was only 0.41 t ha−1 without nitrogen fertilization. Addition of nitrogen fertilizer had no significant effect on yield in unirrigated plants. A single irrigation 60 DAS increased yield due to increase in both grain number and grain weight per ear in fertilized and unfertilized crop respectively. Two irrigations in the unfertilized crop increased the yield to 2.2 t ha−1 while similar treatment in the fertilized crop did not increase the yield significantly. Irrigation increased the WUE for grain yield. The results indicate that nitrogen stress and water stress reduced grain yield primarily through grain number rather than grain weight. Irrigation relieved both water stress and nutrient stress. Nitrogen nutrition was not beneficial under severe water stress conditions but was considerably helpful under mild stress. Biomass, grain yield and harvest index show significant correlation with preanthesis water use.
Tiller Development and Contribution to Yield under Different Moisture Regimes in two Triticum Species
Authors: Mosaad M. G. , Ortiz‐Ferrara G. , Mahalakshmi V.
Published: April 2008

The number of productive tillers is an important yield component in wheat and is affected by water stress and genetic factors. A greenhouse experiment was conducted during spring 1992 at ICARDA, Tel Hadya, Syria, with eight genotypes representing two Triticum species (Triticum turgidum L. ssp. durum and Triticum aestivum L. ssp. aestivum) under four soil‐moisture regimes (95 %, 75 %, 55 %, and 35 % field capacity) to study the effect of water deficit on tiller development and tiller contribution to grain yield. In the highest watering regime appearance of Tiller 1 was delayed in both species. Also Tiller 2 was suppressed in this treatment in durum, while its appearance was delayed in aestivum. In the driest treatment, a majority of the tillers were suppressed and the ones which emerged were delayed. In durum, the heat units required to produce successive leaves on the tillers were higher than that for the main stem and increased with increasing water stress, causing high rate of tiller abortion. In aestivum, each tiller, once produced, developed leaves at the same rate as on the main stem. Phyllochron of tillers as well as main stem was not affected by water stress in aestivum. In aestivum, contribution by tillers to yield was higher than that of durum in all treatments. Results indicate that early appearance of tillers and faster rate of leaf appearance under water stress result in higher tiller survival and greater tiller contribution to final yield. Hence, tiller dynamics under water stress can be used as a selection criterion for breeding for drought tolerance.
Epicuticular Wax of the First Leaves of Two Barley Cultivars Studied by Cryo Scanning Electron Microscopy
Authors: Lyngs Jørgensen H. J. , Lyshede O. B. , Allerup S.
Published: April 2008

Chemical fixation and critical point drying of plant tissue prior to scanning electron microscopy often degrades the outermost layer of the specimen, i.e. the epicuticular wax. Knowledge of the unaltered wax, including its morphology, is important because the wax constitutes the interface between the plant and its surroundings. Having worked previously with barley leaves (anatomy, infection biology of pathogens), we found it of interest to examine and describe the wax morphology on barley leaves and to determine whether or not there were differences between cultivars. Hence, the morphology of the epicuticular wax on the first leaf of two spring barley cultivars has been studied by scanning electron microscopy following cryofixation.

The wax on both cultivars consists chiefly of scales with a small proportion of rods and granules. There is little variation in wax morphology over each leaf side, and only minor differences between the abaxial and adaxial sides of the same leaf. Distinct differences are, however, observed between the two cultivars, especially regarding the thickness and the shape of the wax scales. The wax bodies cover the entire surface of a leaf except for parts of trichomes and guard cells, and some scattered wax free areas.

The morphology and distribution of wax are discussed in relation to studies made on barley leaves using different techniques. Also, the implications of wax morphology for disease resistance are briefly discussed.
Macro‐nutrient Status of Brassica napus and Brassica juncea Grown Under Swedish Conditions
Authors: Kjellström C. , Kirchmann H.
Published: April 2008

Concentrations and amounts of macro‐nutrients (N, P, K, Ca, Mg, S) in shoots, vegetative and generative plant parts in B. napus and B. juncea and nutrient inflow per unit root length in B. napus were studied in a field experiment at Uppsala, Sweden. Concentrations in vegetative plant parts were, except for Ca in B. napus, highest at the beginning of the season, and N and K were higher in B. napus than in B. juncea. The higher N concentration in vegetative parts (leaves, stems and pods) in B. napus was probably due to differences in growth pattern between the species. Seed concentrations of N, P, Ca, Mg and, most pronounced of all, S were higher in B. juncea. Nutrient amounts were, with the exception of K, throughout the season higher in B. juncea than in B. napus due to a higher dry matter production. Nutrient inflow per unit root length in B. napus was highest during the rosette stage for all nutrients. During flowering, the inflow decreased for N and K and increased for P and Ca. After root growth had stopped, no net inflow of K and S was found and inflow rates of other nutrients were at very low levels.
Unterschiedliche technische Behandlung von Gülle und deren Auswirkungen auf intensiv genutztes Dauergrünland
Authors: Elsaesser M. , Kunz H. G. , Briemle G.
Published: April 2008

Technical treatments of slurry and their effects on intensively managed permanent grassland

Since 1987, seven different technical methods for slurry treatments were compared at a permanent grassland sward in South Germany. The effects on botanical composition of the grassland sward, dry‐matter yield and soil nutrient parameters were registered. The experiment includes the variants: mixing with a special slurry pump, separation (liquid and solid phase and composted solid phase), aerification and anaerobic fermentation in a biogas plant. Only slight effects of different treated slurry on the botanical composition could be shown. Comparing with mineral fertilization, the slurry variants had higher proportions of legumes and forage herbs. The dry‐matter yield was not influenced by slurry treated differently. The utilization of slurry nitrogen could be increased on average to 90 % during the experimental period compared to mineral nitrogen. Separation of slurry and fertilization in the liquid phase increased the utilization of nitrogen.
High Temperature Influence 14CO2 Assimilation and Allocation of 14C into Different Biochemical Fractions in the Leaves of Indian Mustard
Authors: Subrahmanyam Desiraju , Rathore V. S.
Published: April 2008

Influence of high temperature stress on photosynthesis and allocation of carbon into different biochemical fractions in mature leaves of Indian mustard [Brassica juncea (L) Czern] was investigated. Heat stress reduced 14CO2 fixation and inhibited the translocation of carbon from the leaves. Allocation of 14C into starch and residue fractions was significantly lower in heat stressed plant leaves. Starch content was significantly reduced in heat stressed plants.
Magnitude of Nitrogen Fixation by Lentil at Different Rates of Phosphorous Using15N Technique
Authors: Badarneh D. M. D.
Published: April 2008

Two lentil cultivars, UJ1 and ILL, have been introduced into the farming system of the Middle East. The influence of P on their potential to fix N2under drought conditions is lacking. A factorial field experiment was carried out at Taibeh (500 mm yr−1) and Muru (300 mm yr−1), where three rates of P, two lentil cultivars and barley were included. Phosphorus was the main plot, while lentil and barley were grown randomly in the subplots. A typical experiment treated with unlabeled 100 kg N ha−1with similar P rates was conducted at the Taibeh site. Both cultivars on each site did not differ significantly at different levels of P regarding the biological yield. At each P level, both cultivars derived similar nitrogen percentages from atmosphere (per cent Ndfa), except at Taibeh with the intermediate rate of P, where ILL derived (66.1 %) compared to UJ1 (40.3 %). At Taibeh, the average percentages of N in the grain and straw were 4.17 % and 1.14%, respectively, and were significantly higher than at the Muru site (3.38 %, 1.29 %). The relatively drought‐like conditions at Muru reduced percentage Ndfa to ∼28 but this was increased by P addition. Nitrogen addition reduced partitioning of N (N index) from ∼0.70 % to ∼0.55 % and decreased P percentage in the grain from ∼0.40 % to ∼0.31 % and in straw from 0.11% to 0.07 % due to early maturation. In spite of the indigenousRhizobiumefficiency to fix N2, only 52.0 % and 42.3 % of the plant N was derived from the atmosphere at Taibeh and Muru, respectively, causing depletion of soil N reservoir.
Effect of Planting Date on the Growth and Yield of Irrigated Sunflower (Helianthus annuus)
Authors: Esechie H. A.
Published: April 2008

The effect of planting date on the growth and yield of irrigated sunflower was investigated in 1992 and 1993. Two sunflower hybrids, Islero and Upsol‐veraflor, were sown at three different dates (3 October, 4 November, 2 December 1992 and 5 October, 6 November, 4 December 1993) in Sultan Qaboos University Agricultural Experiment Station on the Batinah Coast of Oman in a desert climate. Sunflower planted in December emerged later, flowered later and matured later than that planted in October or November. Severity of stalk lodging was closely related to the extent of stem weevil infestation, which was more serious in the early planted sunflower. Sclerotina head rot was also most severe in the October plantings and least severe in the December plantings. Head diameter, number of seeds per head and percentage of large seeds increased with delay in planting date. Seed yield and oil yield were highest in the December planted sunflower but oil concentration was not affected by the planting date. Based on these results, a December planting date was recommended for the Batinah Coast of Oman and other areas with similar climatic conditions.
An Improved Non‐destructive Method for Rapid Estimation of Leaf Area in Sunflower Genotypes
Authors: Nanja Reddy Y. A. , Keshava Murthy M. N. , Virupakshappa K. , Uma Shaanker R.
Published: April 2008

Measurement of total leaf area per plant in crop improvement programmes for a variety of purposes is often very tedious and time consuming. In this paper, we offer a rapid and non‐destructive method of estimating the total leaf area in sunflower at the time of anthesis. We show that multiplying the leaf area of a specific leaf position from the apex by the total number of leaves per plant yields total leaf area with more than 95 % accuracy. The specific leaf position for any given genotype in sunflower can be arrived at by multiplying the total number of leaves per plant by the factor 0.355 and rounding off to the nearest highest integer. This technique can be used for the rapid estimation of leaf area per plant at anthesis for any given genotype of sunflower.
Response of Sweet Potato (Ipomoea batatas Lam.) to Shading at Different Growth Stages
Authors: Oswald A. , Alkämper J. , Midmore D. J.
Published: April 2008

During 1990 and 1991 growth seasons at two locations in Peru four sweet potato cultivars were tested for their response to a short‐term shading. The plants were subjected to artificial shade (42 % light reduction) for 1 month at different growth stages.

A high genetic variability was found in the extent to which tuber and total biomass yield of sweet potato was affected by sub‐optimal light conditions. One cultivar was completely tolerant to shade at all growth stages, whereas the others showed a yield decline between 20 % and 55 %. Generally tuber yield was most reduced when shade was imposed at the end of the growth season (fourth and fifth months) and the least at its beginning (first and second months). Yield losses were due to a diminished biomass production and/or an altered assimilate partitioning within the plant. Tuber formation was affected rather than tuber initiation.
A Proposed Index for Assessment of Row‐replacement Intercropping System
Authors: Banik P. , Bagchi D. K.
Published: April 2008

A new index has been proposed for assessing an intercropping system where the component crops are in row replacement senes. It determines the Actual Yield Loss or gain (AYL) in respect to a component crop in an intercropping situation Here the sown proportion of the component crops with regard to its sole one is to be considered. This index appears to be more appropriate than other established indices like land equivalent ratio, relative yield loss, etc., particularly when per plant yield is considered. Partial AYLs (which are the two components of this index) can be considered as indicators regarding the competition existing between the component intercrops.
Influence Of Tillage On Soil Aeration
Authors: Khan A. R.
Published: April 2008

Air‐ porosity of soil can be altered by tillage. Therefore, it plays a significant role in protecting plants against deficient aeration during critical periods of their life cycle. The effect of five tillage treatments (mouldboard, cultivator, rotary tiller, wedge and zero tillage) and three mulch treatments (paddy straw, rice husk and bare) on the soil oxygen diffusion rate (ODR) during the various growth phases of peanut crop (Arachis Hypogaea L.) were investigated on a lateritic sandy loam soil (utilsol). These experiments were conducted for two consecutive seasons. ODR values were higher in tilled plots. Among tillage treatments, the highest ODR was recorded under mouldboard (60.51 × 10‐8 g cm‐2 min‐1), followed closely by cultivator (57.65 × 10‐8g cm‐2 min‐1), and it was lowest under rotary tiller (46.29 × 10‐8 g cm‐2 min‐1). During the later growth stages and also in lower soil depths, the differences between the values of ODR narrowed down. Among mulch treatments, plots with rice husk (53.98 × 10‐8 g cm‐2 min‐1), had the higher ODR values. Bulk density was lower, whereas total and aeration porosity were higher, under mouldboard and cultivator. Soil temperatures were also higher under mouldboard and cultivator tilled plots.