bluuebunny/crossref_metadata_2025 huggingface dataset:
Allometric Relationships of Growth Components in Maize (Zen mays L.) Cultivars
Authors: Ramachandra Prasad T. V. , Krishnamurthy K. , Kailasam C.
Published: April 2008

Allometric relationship (W1=αW2β, where α and β are the parameters) was fitted among growth components in two maize cultivars viz., Decani hybrid and Deccan 101 in order to obtain estimates of other components of the plant system which are time consuming measurements. The results of the agronomic field trial conducted at the University of Agricultural Sciences, Bangalore were used. This model's predictability was compared with linear regression model. In both the cultivars, allometric model using leaf area (LA ‐ W2.) and leaf dry matter (LDM ‐ W2) simulated total dry matter production (DMP ‐ W2) by 79 to 98 % of actual values. Further allometric model fitted well to predict stem dry matter by 91 to 93 % using LDM and LA 89 to 92 % using LDW. Whereas linear regression model estimated total DMP by 95 to 96 % using cob dry matter. In case of LDM ‐ LA association, linear regression model was found to be the best than other model. The leaf area decreased after silking in both the cultivars and the ratio of growth rates of DMP – LA (β2) was negative. Between cultivars, cv. Deccan 101 had higher R2 values in most of the relationships than cv. Deccan hybrid indicating the varietal difference.
Smut Incidence and Yield Losses of Corn Cultivars under Different Plant Population Densities
Authors: Kostandi S. F.
Published: April 2008

Six corn cultivars were grown, under field conditions, at two population densities of 14285 and 22875 plants/ acre. All were subjected to an artificial infection at 6‐leaf growth stage to determine their reactions to smut disease and yield losses. Changes in plant chemical composition, including K and N contents of ear‐leaf, were performed at silking stage. The results showed that corn cultivars imposed wide variations to smut reaction. Susceptibility to smut disease was less prevalent on D.H 204 and 3‐way cross 310 and more abundant on D.H 215, Iskandria 11 and El‐Kabera 1. The corn cultivar Giza 2 appeared an intermediate reaction. Smut incidence at high population density was markedly depressed by 6.6 % below the comparable level at low population rate. Differences in yield losses between low and high plant population densities were actually limited for smut resistant cultivars, while the opposite was true for the more susceptible ones. On average, the yield losses at the low population density varied from 2.5 % for D.H 204 to 14.4 % for Iskandria 11. The calculated losses of the respective cultivars declined to 2.3 and 9.2 % at the thicker stand. The overall effect of increasing smut infection on yield losses, as revealed from the regression coefficients of the response curves, was clearly pronounced at the higher plant population, whereas the yield was substantially improved by 9.7 %. Varietal response to smut performance was explained on the basis of vigor growth and K/N ratio of ear‐leaf.
Effect of Inoculant Rate on Nodulation and Various Agronomic Traits of Soybean
Authors: Papakosta D. K.
Published: April 2008

In a soil lacking indigenous Bradyrhizobium japonicum, soybean (Glycine max [L.] Merr.) nodulation depends upon the number of rhizobia applied with the inoculum. This field study reports the effect of different rates of applied rhizobia on nodulation, dry matter and nitrogen content in soybean in a Mediterranean soil lacking B. japonicum.

Treatments included six rates of B. japonicum, ranging from 2.5 × 104 to 6.075 × 106 rhizobia cells per seed applied to the seed as peat inoculant at planting, 100 kg N ha−1 and an uninoculated control. The experiment was conducted in an Entisol soil. Regression analysis showed linear relationship between the rate of applied rhizobia and the number of the nodules per plant or the dry weight per nodule. In early stages of development (32 and 68 days after planting) plant dry weight was not affected by inoculation rate. At harvest a rate of 7.5 × 104 rhizobia cells per seed was necessary for maximum total and stover dry weight. A higher rate, 6.75 × 105 rhizobia cells per seed, was required to obtain maximum grain yield, total N content in plant tops and grain N content. Grain percentage N was increased up to 2.025 × 106 rhizobia cells per seed. Nitrogen application increased grain yield, total N content and grain N content at the same level as the lower inoculation rate.
Effects of Two Underseed Species, Medicago polymorpha L. and Scorpiurus muricatus L., on the Yield of Main Crop (Durum Wheat) and Subsequent Crop (Teff) Under Humid Moisture Regimes in Ethiopia
Authors: Pülschen L.
Published: April 2008

Mixed cropping of leguminous underseed species and cereal crops may increase productivity and serve some additional purposes. Two leguminous weed species which are widely distributed in annual crops of the Ethiopian highlands have been studied with varying coverage in greenhouse trials in Ethiopia with regard to their suitability as underseeds and with wheat (Triticum turgidum [L.] Thell. var. durum [Desf.] MacKey) as a main crop. The competitive effects of Scorpiurus muricatus L. on the grain yield of wheat were smaller than those of Medicago polymorpha L. (‐14.1 % and ‐23.6 % respectively, compared with the underseed free control) which is mainly ascribed to differences in their speed of development and shoot height. The residual effects of the underseed's root masses on the grain yield of the successive teff crop (Eragrostis tef [Zucc] Trotter) were significantly higher with Scorpiurus muricatus (+99.3 %) than with Medicago polymorpha (+63.6 %). The results are discussed with regard to the specific site conditions in the cereal‐dominated cropping systems of the Ethiopian highlands.
N‐Aufnahme und ‐Verwertung verschiedener N‐Düngerformen durch Winterweizen – Gefäßversuche mit 15N
Authors: Müller S.
Published: April 2008

N‐uptake and N utilization of different fertilizer types by winter wheat – pot experiments with 15N

The efficiency of top dressing urea, ammonium nitrate and ammonium sulphate fertilizers on winter wheat grown on loamy sand and loessial black soil was studied. At a rate of 0.5 g N per pot on the loamy sand 20 % volatilization losses of NH3 occurred with urea and 10 % on the loessial black soil with urea resp. ammonium sulphate.

The grain yields an N removal correspond to these results. At an amount of 1.6 g N per pot the N‐uptake of 15N ranged from 0.589 g (urea) on sandy soils to 1.279 g (ammonium nitrate) which agrees with 76 % an 91 % of the total N uptake. On black soil 0.675 g (urea) and 1.038 g (ammonium nitrate) or 44 % and 51 % of the total uptake are found.
Endosperm Development in Maize and Related to Photosynthate Supply
Authors: El Sayed H.
Published: April 2008

Maize (Zea mays, L. Sweet Corn) plants were given shaded, partially shaded and control light treatments during 10 days or 20 days periods around the time of pollination. Glucose, sucrose, starch and dry matter (DM) contents were measured at intervals in composite samples of pericarp/nucellus (PN), and in endosperms taken from developing kernels. Total kernel DM per ear at maturity was higher in the partially shaded treatment than control and shaded treatments due to higher kernel set in apical regions of ears. In PN at 11 days after pollination (DAP), DM and sucrose contents were slightly greater in partially shaded than control and shaded plants. Glucose contents were substantially greater than controls in PN of partially shaded plants and were less than control in shaded plants. In endosperms from apical kernels at 5 to 10 DAP (during cell division), DM, glucose and sucrose contents were substantially less in shaded than control and partially shaded plants, sucrose contents were greater in endosperms of partially shaded than control plants. Sugar contents in endosperms from basal kernels were nearly the same in the three light treatments. At 10 DAP, apical and basal endosperms in shaded plants had fewer nuclei than those of the other light treatments. The light treatments appeared to effect apical kernel growth by influencing the extent of cell division.
Ammonia Metabolism in the Leaves and Ears of Wheat (Triticum aestivum L.) During Growth and Development
Authors: Maheswari M. , Nair T. V. R. , Abrol Y. P.
Published: April 2008

The pattern of free NH4+ accumulation and its metabolism was studied during the growth and development of field‐grown wheat cv. HD 2204 at two applied N levels viz. 30 and 120 kg ha−1. The study was confined to the 3rd, 5th and flag leaf blades and the developing ears, borne on the main shoot, during their ontogeny. The NH4+ levels were considerably lower in young leaves and increased sharply as the leaves senesced when the activity of glutamine synthetase (GS) declined. In contrast to GS, glutamate dehydrogenase (GDH) remained active even during senescence. Concentrations of protein, free amino acid and total reduced N declined with age in the leaves. An assessment of free NH4+ pool, free amino acid content and the activity of GS and GDH in the floral parts revealed that glumes, awns and grains also were active sites of NH4+ turnover. Higher applied N level not only increased leaf and grain N concentration but also led to higher free NH4+ levels in leaves and in developing ears. Presence of NH4+ in the entrapped transpirate revealed that NH4+ is released from both leaves and ears during senescence.
Yield and Agronomic Characters of Tropical Maize (Zea mays L.) Cultivars under Different Irrigation Regimes
Authors: Weerathaworn P. , Thiraporn R. , Soldati A. , Stamp P.
Published: April 2008

Drought spells are unpredictable under tropical conditions and can occur at every growth stage of the maize plants. Little is known about the reactions of tropical maize cultivars to water shortage. A set of Thai cultivars was examined in the field during the dry season. Three stress situations were imposed: prolonged stress throughout the growing season, pre‐ and post‐anthesis stress. Pre‐anthesis water stress delayed flowering and especially the data of silking. Thus, the anthesis‐silking interval was wider. Prolonged water stress decreased grain yield mainly due to a low number of kernels and/or thousand kernel weight (TKW). Post‐anthesis stress mainly reduced TKW grain set per ear. Relief from pre‐anthesis stress increased grain yield by a grater number of kernels and higher TKW as compared to prolonged stress. Genotypic differences were high for the anthesis‐silking interval following pre‐anthesis stress. Low yielding, early but generally drought‐stable cultivars existed as well as cultivars which were generally high yielding even under water stress because of a good residual yield. Some cultivars were resistant to pre‐anthesis stress but not to post‐anthesis stress and vice versa. It can be concluded that ample genotypic variability exists for adaptation to varying situations of pre‐and post‐anthesis stress within tropical maize cultivars.
Yield, Quality and Nitrogen Efficiency in Winter Wheat Fertilized with Increasing N Levels at Different Times
Authors: Miceli F. , Martin M. , Zerbi G.
Published: April 2008

Particular problems in N fertilization of winter wheat are found in areas characterized by excessive drainage and rainy springs. A two yearly experiment was carried out in such an environment (Udine, northern Italy) with the objective of testing the effect of increasing levels of total N supply (0, 70, 140 and 210 kg ha−1) and of different times of late N side‐dressing (at stem elongation, booting or flowering) on yield, quality traits and on N use efficiency of the wheat cv. Saliente.

The results obtained indicated that yields of about 5 t ha1 can be obtained if the N supply permits a crop recovery of 130‐140 kg ha−1. Supplying the last N fraction at booting increased the fertility of the spike, the overall quality of the product and the efficiency of the fertilization. N supply can be delayed to flowering time in case of high total N, with further positive effects on the quality of the product. The nitrogen use efficiency was inversely and linearly related to total N supply.
Maize‐Soybean Intercropping: Effect of Different Variety and Sowing Density of the Legume on Forage Yield and Silage Quality
Authors: Andrighetto I. , Mosca G. , Cozzi G. , Berzaghi P.
Published: April 2008

Two studies were carried out to evaluate the effect of different agronomic solutions on the quanti‐qualitative yield of maize‐soybean intercropping for silage production.

In the first year the research compared the use of two hybrids of the cereal (Lorena and Luana) as control and in association wirh soybean varieties of different maturity group [Futura (I) and King (II)]. In the following growing season the two sowing densities of the soybean (20 vs 40 p/m2) were analyzed.

In both trials the intercropping gave a production similar to that obtained from the cereals control while its protein content was significantly higher.

The maturity group of soybean did not modify yield and chemical composition of the intercropping. This could have been arisen from the unfavourable climatic conditions of the first growing season. In the same trial it appeared the possibility of altering the intercropping yield and composition by choosing the maize hybrid.

The suitable water availability for the cereal recorded in the second study, increased the maize yield reducing the difference in composition between pure crop and mixed forage.

The sowing density of the soybean did not affect the productive response of the intercropping.

Maize‐soybean intercropping did not show any detrimental effect during ensiling and ensiling losses were similar to those of the maize silage.
Effect of Seed Coating on Yield Attributes and Yield of Soybean (Glycine max L.)
Authors: Jeyabal A. , Kuppuswamy G. , Lakshmanan Ar.
Published: April 2008

Investigations were carried out during March to June 1991 to evaluate the effect of seed coating with organic, inorganic nutrients and biofertilizers on yield attributes and yield of soybean under three environments with different soil types viz., clay loam, sandy clay loam and sandy loam. Seed coating with bio‐digested slurry 50 per cent, superphosphate 2 per cent, Bradyrhizobium 2 per cent, and Phosphobacteria 2 per cent (w/w of seed) increased the number of filled pods and grain yield by 29.6 and 37.2 per cent, respectively over the uncoated. There was a significant increase in the test weight of grains due to seed coating with Phosphobacteria. Environment with clay loam soil was found to be highly responsive to seed coatings.
14CO2 Assimilation and Translocation of 14C‐Photosynthates by Different Parts of Indian Mustard (Brassica juncea L.)
Authors: Subrahmanyam D. , Rathore V. S.
Published: April 2008

The role of leaves, stem and reproductive parts in 14CO2 fixation and subsequent photosynthate translocation was studied in Indian mustard (Brassica juncea L.) at three growth stages. The data indicated that leaves, stem and pods are important sources of photosynthates for seed filling. At bud emergence stage leaves are the principle site of 14CO2, fixation. The contribution of leaves declines at subsequent stages, where as the contribution of pod walls increased from bud emergence stage to ripening stage. The contribution of the stem remains more or less constant at all three growth stages studied. Although stem can fix 14CO2, at bud emergence and flowering stages it imported 14C‐photosynthates from leaves. However, stem exported photosynthates during subsequent growth stages.
Effects of Induced Epidemics of Heterodera glycines, Diaporthe phaseolorum var. caulivora, and Pseudomonas syringae pv. glycinea in Single Inoculations or in Combinations on Soybean Yield and Other Agronomic Characters
Authors: Pacumbaba R. P.
Published: April 2008

The effects of induced epidemics of Heterodera glycines (Hg), Diaporthe phaseolorum var. caulivora (Dpc), and Pseudomonas syringae pv. glycinea (Psg) in single inoculations or in combinations on soybean yield and other agronomic characters were studied in the field for 3 planting dates from 1985–1987. Agronomic characters, such as size of nodules, number of pods, plant heights, yields, and disease ratings and infestations of soybean were noticeably influenced by the induced epidemics of the pathogens affecting soybeans. Similarly, the induced epidemics of these pathogens also produced either a negative or positive correlation coefficient of the various indicated agronomic characters. Synergistic‐yield loss interaction between Dpc + Psg was positive. However, the synergistic‐yield loss interactions between Dpc + Hg, Hg + Psg, and Dpc + Hg + Psg were negative. Based on the symptomatology of the diseases, there were no synergisms noted on soybean.
Untersuchungen zum Einfluß von Konkurrenz auf die Bestandesentwicklung von Sommerraps bei unterschiedlicher Gunst der Umweltbedingungen
Authors: Geisler G. , Shrief S. A. , Ibrahim A. F. , Shabana R.
Published: April 2008

Investigations on the effect of competition with regard to the stand development of spring oilseed rape as dependent on environmental conditions

Field experiments were conducted to investigate the frequency distribution in spring oilseed rape as dependent on environmental growing conditions and plant density. As measures for frequency distribution skewness and kurtosis were estimated. The plant character determined was single plant dry matter. To understand the changes in the stand structure, samples were taken at the following developmental stages: rosette, begin of flowering, end of flowering and ripeness (harvest). Plant densities ranged from 60 plants/m2, 90 plants/m2 till 120 plants/m2

The results show that under unfavourable growing conditions, generally speaking, the values of (positive) skewness and kurtosis increase with the development of the plants; under favourable growing conditions, however, the values of skewness and kurtosis decrease from rosette till harvest.

Under unfavourable growing conditions as well as favourable ones, the values of skewness and kurtosis increase with strengthening of plant competition as consequence of increasing plant density. However, the trend during development and the height of the values as well as the quantitative relationships are strongly controlled by the general growing conditions. Frequency distribution, therefore, is not only a result of plant competition but also of differences in resources due to the general conditions of the location.
Maintenance of Vigour and Viability of Stored Pea (Pisum sativum L.) Seeds
Authors: Ramamoorthy K. , Kalavathi D. , Paramasivam M.
Published: April 2008

To determine the most efficacious midstorage hydration‐dehydration treatment for preservation of vigour and viability of stored pea seeds (Pisum sativum L.), cultivar Bonneville, three methods viz., soaking‐drying, moisture equilibration‐drying and moist sand conditioning‐drying each at varying durations were evaluated. Irrespective of the durations of treatment, soaking‐drying proved injurious. Though all durations of moisture equilibration excepting and 120 h outperformed the control, yet 48 h proved to be the best. Preconditioning with moist sand (5 % moisture content) with seed at a ratio of 1: 2.5 for different durations revealed 48 h to be the optimum, 72–96 h to be innocuous and thereafter injurious. Maintenance of membrane integrity and counteraction of lipid peroxidation may be the possible reasons for such beneficial effects.
Effect of Antitranspirants on Leaf Temperature Transpiration Rate and Diffusive Resistance in Brinjal Plants
Authors: Prakash M. , Ramachandran K. , Nagarajan M.
Published: April 2008

Brinjal plants (Solanum melongena L.) grown under moisture stress conditions in glasshouse were treated with three chemicals namely, cycocel, limewash, and potassium chloride to study their effect on leaf temperature, transpiration rate and diffusive resistance. Moisture stress imposed at three stages increased leaf temperature and diffusive resistance but decreased transpiration rate. Application of antitranspirants decreased leaf temperature and transpiration but increased diffusive resistance.
Evaluation of Certain Sugarcane Varieties for Ethanol Production
Authors: Rakkiyappan P. , Pandiyan R.
Published: April 2008

Field experiment was conducted to study the ethanol yielding ability of twenty‐three sugarcane varieties during 1987–88 at Sugarcane Breeding Institute, Coimbatore, India. Among the varieties studied, Co 8145 yielded the highest quantity of ethanol (13,619 1/ha) and Co 1305 yielded the lowest (5,579 1/ha). Apart from Co 8145, varieties CoSi 86071, Co 6304, Co 975 and Co 7219 were also found promising which yielded alcohol above 12,000 1/ha. Total sugars had a positive association (r = 0.974**) with fermentable sugars in juice. Ethanol yield per unit volume of juice (actual yield) had a significant positive association with total sugars (r = 0.818**) and fermentable sugars (0.942**) in cane juice. Cane yield had a direct bearing on ethanol yield as evidenced from the highly significant positive correlation between them (r = 0.890**). Hence a variety meant for ethanol production should contain high total and fermentable sugars in juice coupled with high cane yield and juice extraction per cent. These high yielding ethanol varieties viz., Co 8145, Cosi 86071, Co 6304, Co 975 and Co 7219 may be exploited for commercial production of ethanol directly from juice and used as parents for evolving cane varieties meant for ethanol production.
Behaviour of Polyphenol Oxidase, IAA Oxidase and Catalase in Germinating Rice in Relation to Salt Tolerance
Authors: Mittal Renu , Dubey R. S.
Published: April 2008

Activities of the enzymes polyphenol oxidase, indole‐3‐acetic acid (IAA) oxidase and catalase were compared from endosperms and embryoaxes of germinating rice (Oryza sativa) seeds of two sets of cultivars differing in salt tolerance, raised under increasing levels of NaCl salinity. Salt sensitive cvs. Ratna and Jaya were characterized by higher polyphenol oxidase activity in embryoaxes under salinisation as compared to salt tolerant cvs. CSR‐1 and CSR‐3. In endosperms of salt sensitive cultivars the enzyme activity decreased under salinisation whereas in tolerants it increased due to salinity. In vitro studies using desalted enzyme extracts showed a continuous increase in polyphenol oxidase activity with increasing concentration of NaCl (0–1000 mM) in the reaction medium. IAA oxidase activity increased due to salinity in embryoaxes of both sets of cultivars, the effect was greater in sensitive cultivars than tolerants. NaCl when incorporated in the reaction medium caused decrease in IAA oxidase activity. Activity of catalase decreased with increase in salinity with greater decrease in sensitive cultivars than tolerants. Results suggest possible different behaviours of oxidative enzymes in germinating seeds of rice cultivars differing in salt tolerance and that salt tolerance ability is associated with lower polyphenol oxidase and IAA oxidase activities and higher catalase activity in embryoaxes under salinisation.
Influence of NaCl Salinity on Behaviours of Nitrate Reductase and Nitrite Reductase in Rice Seedlings Differing in Salt Tolerance
Authors: Katiyar Sadhana , Dubey R. S.
Published: April 2008

Activities of enzymes nitrate reductase (NR) and nitrite reductase (NiR) were determined in rice seedlings differing in salt tolerance raised under increasing levels of NaCl salinity. Salinity caused marked increase in in vivo NR activity in roots and shoots of salt tolerant cvs. CSR‐1 and CSR‐3 whereas in salt sensitive cvs. Ratna and Jaya a marked inhibition in in vivo NR activity was observed under salimzation. Under both controls as well as salt treatments in all cultivars roots always maintained higher level of in vivo NR activity than shoots. In vitro NR activity increased in both roots and shoots of all cultivars during early days of growth with maximum at 10–15 days and decreased thereafter. In salt tolerant cultivars salinity caused an increase in in vitro NR activity in shoots but not in roots whereas in salt sensitives activity of the enzyme was always more in salt stressed seedlings compared to controls. Salinity increased NiR activity in seedlings of sensitive cultivars whereas in tolerants suppression in root NiR activity was observed due to salinity. Like NR the activity of NiR was also higher in roots than shoots. 1 M NaCl in the enzyme assay medium suppressed in vivo NR activity in roots of 15 days old nonsalinized seedlings with more suppression in sensitive cultivars than tolerants. Results suggest possible different behaviours of nitrogen assimilatory enzymes in rice cultivars differing in salt tolerance and that salt tolerance ability is associated with high in vivo NR activity in seedlings and its further activation under salinization.
The Influence of Different Nitrogen Levels and Seeding Rates on the Dry Matter Production and Nitrogen Uptake of Spelt (Triticum spelta L.) and Wheat (Triticum aestivum L.) under Field Conditions
Authors: Rüegger A. , Winzeler M. , Winzeler H.
Published: April 2008

Dry matter production of two different spelt (Oberkulmer, Hercule) and wheat varieties (Arina, Iena) were investigated at two different seeding rates (S1 = 200 grains/m2; S2 = 400 grains/m2) and two nitrogen levels (N1 = 80 kg N/ha; N2 = 110 kg N/ha). The plot experiments were carried out at two contrasting locations (Muri: altitude 459 m asl); Oberwallestalden: altitude 1011 m asl) over three years (1988–1990). In addition nitrogen uptake and the photosynthetic rate of flag leaves was measured. Neither growth regulators nor fungicides were applied.

The average grain yield of spelt was 25 % lower than that of wheat (32 % at Muri, 18 % at Oberwallestalden). At the reduced seeding rate (S1) grain weight and grain number per ear was increased by 33 % and 31 %, respectively as compared to the normal seeding rate (S2). The increase of the grain weight and the grain number per ear was larger for the two varieties of spelt (47 % and 42 %, respectively) than for the wheat varieties (23 % and 22 %, respectively).

The photosynthetic rate of the flag leaf of spelt and wheat was not significantly different, at the two growth stages measured (anthesis, anthesis + 23 days).

Nitrogen yield in the above ground biomass (g N/m2) was not significantly different between spelt and wheat, neither at the beginning of stem elongation, nor at anthesis. At anthesis the nitrogen yield at the reduced nitrogen level (N1) was 16 % and 13 % lower than at the higher level (N2) for spelt and wheat respectively. A higher nitrogen efficiency of spelt under low input conditions was not apparent.

Therefore it was concluded that under low input conditions, spelt is not more efficient in dry matter production than wheat. By comparing the “husked” yield of spelt (grains + glumes; representing the trade form) with the grain yield of wheat, spelt is higher yielding than wheat but only at marginal areas of cereal production.
Level and Nature of the Resistance to the Cereal Aphid, Sitobion avenae (F.), in Thirteen Winter Wheat Cultivars
Authors: Havličková Helena
Published: April 2008

Thirteen winter wheat cultivars were tested under field and greenhouse conditions for resistance to the cereal aphid, Sitobion avenae (F.). Marked differences were recorded between cultivars in nonpreference (anti‐xenosis), antibiosis and tolerance to aphids. Nonpreference was significantly (P < 0.001) correlated with antibiosis measured in terms of the biomass of aphids on naturally and nonsignificantly (P > 0.1) on artificially infested ears (criterion for cultivar antibiosis). Over all the cultivars, there was no correlation between nonpreference and tolerance and between antibiosis and tolerance to aphids.

Five cultivars expressed high level of resistance to S. avenae. The high resistance of three cultivars was due to high nonpreference and antibiosis, and only in two cultivars all three mechanisms contributed to resistance.
Non‐Destructive Estimation of Leaf Area in Cocoyam (Xanthosoma sagktifolium [L.] Schott)
Authors: Agueguia A.
Published: April 2008

Leaf area of cocoyam (Xanthosoma sagittifolium) can be estimated quickly and accurately using the mathematical relationship between linear measurements of leaves which relate leaf area (Y) to the product of length (L) and breadth (B).The most accurate relationship is Y = K (LB) with K = 0.923 + 0.004.
Productivity of Barley Infested with Russian Wheat Aphid [Diuraphis noxia (Kurdjumov)]
Authors: Robinson J.
Published: April 2008

Resistance to Russian wheat aphid, [Diuraphis noxia (Kurdjumov)], was studied in barley, (Hordeum vulgare L.), based on maintenance of plant height, spike number, straw weight, grain yield and kernel weight. The experiments comprised small plots artificially infested with the aphid, plots naturally infested, and plots regularly sprayed with insecticide. Seven symptomatically resistant and five symptomatically susceptible barleys were compared. Mature plant height of the resistant barleys, compared with the susceptible barleys, was better maintained in the artificially infested plots. Spike number, straw weight, grain weight and kernel weight were also better maintained in the resistant accessions than in the susceptible ones. Gloria/Come, symptomatically resistant, did not perform well over the parameters measured. The susceptible varieties Esperanza and Shyri were severely affected by the aphid in terms of the measured traits. Grain yield of infested plots as a percentage of control plots ranged between 50 and 77 %; spike number between 66 and 96 %; straw weight betwen 62 and 78 %, and kernel weight between 70 and 84 %. Genotypes Barberousse/ Rumorosa//Gloria/Come and Barberousse/3/ASE/2CM//B76BB/4/Gloria/Come were the most resistant accessions. Selection of barley genotypes based on visual assessment of symptoms in artificially infested hill plots facilitates selection of genotypes that maintain their yield in artificially infested plots sown at commercial rates. These D. noxia resistant barleys are widely adapted and of good agronomic type, and will be useful to barley growers where the aphid is a pest.
Direct and Residual Effect of Different Organic Fertilizers on Potato and Cereals
Authors: Kanal A. , Kuldkepp P.
Published: April 2008

Field experiment with 8 different organic fertilizers (cattle dung with and without litter, pig slurry, peat compost formed from hen and pig slurry, sawdust‐duck manure, noncomposted peat and straw litter with pig slurry) was carried out on loamy brown podzoluvisol since 1985.

The organic fertilizers were applied in the spring of 1985 on two backgrounds: with and without mineral fertilizers. The material is based on the data of four years (1985–1988). The arrangement of crops was the following: potato, spring wheat, barley and early barley.

On both backgrounds cattle dung with litter turned out to be the best organic fertilizer, while noncomposted peat manure had a low direct and residual effect. However, before the application it must be composted with pig or hen slurry. The effect of peat composts was dependent on the background of mineral fertilizers. Pig slurry had a low residual effect and acted only as a liquid nitrogen fertilizer. The joint application of straw and pig slurry can be a suitable opportunity for diminishing their undesirable effects.
Stress Studies in Lentil (Lens esculenta Moench)
Authors: Singh B. B. , Tewari T. N. , Singh A. K.
Published: April 2008

A pot experiment was conducted to see the effect of varying levels of soil sodicity on leaf growth, nitrate reductase activity, nodule development and nitrogenase activity in two lentil (Lens esculenta Moench) genotypes. It was observed that in both the genotypes increasing level of soil sodicity decreased the plant height, leaf area, leaf dry weight, total biomass production and finally the grain yield. Nitrate reductase activity in leaf tissues and concentration of total nitrogen in different plant organs showed significant reduction with increase in soil sodicity. Increasing soil sodicity (15 and 20 ESP) was not only deleterious to nodulation and nitrogenase activity but also caused complete failure of nodulation process at 25 ESP of soil. Reduction in aforesaid characters due to increasing soil sodicity was less in variety PL‐406 than that of local indicating thereby the relative tolerance of PL‐406 to sodicity.

Prolonged and higher activities of nitrate reductase and nitrogenase at higher sodicity level in PL‐406 might be the reasons for superiority of this variety. Significant and positive correlations were also observed between leaf characters and nitrogenase activity.
The Effect of Nitrogen and Phosphorus Fertilization on the Phosphorus Absorption by Sunflowers
Authors: Loubser H. L. , Human J. J.
Published: April 2008

Little is known about the effect of fertilization on the P uptake of sunflowers. A 42 factorial trial with 0, 60, 120 and 180 kg N ha−1 and 0, 15, 30, and 45 kg P ha−1 was conducted over three years. The P content and concentration of leaves, stems and capitula were determined at three growth stages. High N levels increased the P content and concentration of all plant components in early growth stages only. High P levels increased the P content and concentration of all plant components sharply almost throughout. Plants seem to recover some lost growth towards the end of the season so that at physiological maturity there are no significant differences in P content among N levels. The translocation of P from the stems is very effective but P can accumulate in the leaves if a luxury quantity of P is present in the plants. In terms of seed yield a significant N × P interaction was found, indicating a sharp response to both N and P only in the presence of a sufficient quantity of the other element. The response of seed yield was in agreement with the P absorption by the plants.
Changes of Surface Potential and Phospholipid Composition of Winter Wheat Callus Cells Grown at 5 and 25 °C
Authors: Filek M. , Pazurkiewicz‐Kocot K. , Dubert F. , Marcińska I. , Biesaga‐Koscielniak J.
Published: April 2008

The surface potantial (Es), lipids content and the contents of main phospholipid fractions, i.e. PC, PE and PI, in callus from the mesocotyl part of mature embryo of winter wheat var. Grana have been estimated. Callus was obtained by the endosperm supported induction. Measurements were repeated during callus vegetation at 25 °C for 35 days or at 5 °C for over 50 days.

The transfer of callus to cold caused a temperature stress and as result Es decreased almost twice. However, during further growth of callus at low temperature a nearly linear increase of the potential took place. During this time small green areas with densely packed cells appeared. The surface potential of the centres was different from that measured in the non‐differentiated part of callus. Moreover, this potential was entirely independent of the temperature and time of callus growth. Some evidences indicating that the differences in the surface potential of callus cells precede the appearance of visible differentiating structures were also obtained.

At 5 °C the content of main phospholipid fractions initially grew and then their quantities distinctly diminished. During callus growth at 25 °C remarkable differences in the concentrations of PC and PE were observed and only PI contents systematically lowered. A significant negative correlation between PI concentration and surface potential (independent of temperature of growth) was obtained.

As the differentiation process in callus progressed, the percentage content of PE fraction was increased.
Limits to Retention of Fertilized Flowers in Faba Beans (Vicia faba L.)
Authors: Stoddard F. L.
Published: April 2008

Factors affecting the retention of faba bean flowers and their development into pods werde investigated. Racemes were scored for the date of anthesis of the first flower, and at maturity, the number of pods that developed. These data were correlated with meteorological data. The primary determinant of whether a flower would be retained was the weather during the 4 days from anthesis: incident light and rainfall accounted for over 55 % of the variation in the retention of flowers within a genotype. The results help to validate the model that the availability of assimilate at the time of pod setting is critical for the development of adequate yield. In some environments, such as the winter‐rainy Mediterranean climate, available light at flowering may be a major yield‐limiting factor.

Begrenzende Faktoren für den Ansatz befruchteter Blüten bei Fababohnen (Vicia faba L.)

Es wurden Faktoren untersucht, von denen der Ansatz der Fababohnenblüten und ihre Entwicklung in Hülsen abhängig ist. Die Blütenstände wurden hinsichtlich des Termins des Blühbeginns der ersten Blüte, der Reife und der Anzahl der enrwickelten Hülsen bestimmt. Diese Angaben wurden mit meteorologischen Daten korreliert. Die erste Bestimmungsmöglichkeit hinsichtlich des Ansatzes einer Blüte ergab sich aus den Witterungsbedingungen während der ersten vier Tage nach Blühbeginn: Lichteinfall und Niederschlag kontrollierten mit mehr als 55 % die Variation des Ansatzes von Blüten für den jeweiligen Genotyp. Die Ergebnisse bestätigen Modellvorstellungen, daß die Verfügbarkeit von Assimilaten zum Zeitpunkt des Hülsenansatzes für die Entwicklung eines angemessenen Ertrages kritisch ist. In einigen Umwelten, so z. B. der Winterniederschlag mediterranen Klimas, weist auf die Bedeutung des verfügbaren Lichtes während der Blüte als ein Hauptfaktor hin, der hinsichtlich der Ertragsbegrenzung wirksam wird.
Effect of Shading on the Growth and Yield of Mungbean (Vigna radiata [L.] Wilczek)
Authors: Islam M. T. , Kubota F. , Mollah F. H. , Agata W.
Published: April 2008

Mungbean grown as intercrop suffers shading stress form companion crop at different growth stages. Grain filling stage, which appears to be very much sensitive to light conditions, needs special attention to deal with, in order to maximize the benefit from intercropping systems. Growth and yield response of mungbean to different shading conditions imposed at the onset of pod formation stage was evaluated. Shading nets were used to cut down the incident photosynthetic active rediation by 15 %, 45 % and 75 %. There was almost no difference between the control and 15 % shaded plants for all the parameters studied. Total dry weight was found to decrease with increase in shading intensity and this phenomenon continued till the maturity of the crop. The crop growth rate, relative growth rate and net assimilation rate decreased due to shading. Lower specific leaf weight and higher chlorophyll content were due to increased shading. Decreased photosynthetic active radiation caused significant reduction in pods per plant and thus there was a significant decrease in seed yield per plant. In order to avoid yield loss due to shading at grain filling stage, agronomic manipulation and selection of suitable genotypes are necessary.
Studies on Nitrogen Economy and Productivity of Wheat as Affected by Rainy Season Legumes under Irrigated Conditions
Authors: Singh S. , Ahlawat I. P. S. , Ahuja K. N.
Published: April 2008

A field experiment was conducted during July 1986–April 1988 at New Delhi, to evaluate the relative contribution of rainy‐season legumes towards the growth and productivity of succeeding wheat (Triticum aestivum [L.] emend. Fiori & Paol), find out economic optimum dose of nitrogen for succeeding wheat and screen a legume which can be best knitted in wheat based cropping system.

HD 2329 wheat performed better when grown after legumes than when grown after Local fodder sorghum (Sorghum bicolor [L.] Moench). N economy in wheat was greater (65–78 kg/ha) after Sona clusterbean (Cyamopsis tetragonoloba [L.] Taubert) and T‐9 blackgram (Phaseolus mungo L.) over sorghum. The economic optimum dose of N for wheat following pigeonpea (Cajanus cajan [L.] Millsp.), soybean (Glycine max [L.] Merr.), groundnut (Aracbis bypogaea L.), blackgram (Phaseolus mungo L.) and clusterbean were 110.1, 103.6, 113.7, 109.6 and 92.3 kg/ha respectively.
Lichtaufnahme und Stoffproduktion eines konventionellen und eines epigonalen Genotyps der Weißen Lupine (Lupinus albus)
Authors: Aufhammer W. , Stützel H. , Rautenkranz A. , Falfus J. , Nalborczyk E.
Published: April 2008

Light interception and dry matter production of a conventional and an epigonal genotype of the white lupine (Lupinus albus)

Yield formation of two white lupin (Lupinus albus) genotypes differing substantially in growth habit was investigated. Grain production was quantified as the product of harvest index and dry matter production, the latter being a function of light interception and utilization. Experimental data were obtained from two‐year field experiments with a combined variation of plant density and distribution. The conventional, freely branching cultivar Kalina showed higher leaf area indices and growth rates than the “epigonal” (little branching) genotype. The higher growth rates of Kalina were partly due to increased light interception, but were mainly a result of a higher light use efficiency. This can be explained with a more even light distribution over a greater leaf area. The more rapid increase of the harvest index in the epigonal genotype compared to Kalina only partially compensated for the differences in dry matter production.
Correlation Studies on Ammonium/Nitrate Concentrations in Soil and Growth and Yield of Wheat
Authors: Joseph P. A. , Prasad Rajendra
Published: April 2008

A field experiment was conducted at the Indian Agricultural Research Institute, New Delhi to study the growth and yield of wheat as influenced by the concentrations of ammonium‐N and nitrate‐N in soil. A series of ammonium and nitrate nitrogen concentrations in soil on a time frame was developed by treating prilled urea with nitrification inhibitors DCD or neem cake as well as by changing the dose and time of N application. The study revealed that number of tillers m‐1 as well as ears m‐1 row length were significantly positively correlated with ammonium‐N concentration at 15 and 30 DAS and nitrate‐N concentration at 30 and 45 DAS. Number of grains ear‐1 was significantly positively correlated with ammonium‐N at 30, 45 and 60 DAS and nitrate‐N at 45 and 60 DAS. Ultimately grain yield in wheat was significantly positively correlated with ammonium‐N concentration at 15 and 30 DAS and nitrate‐N concentration at 30, 45 and 60 DAS. The response between grain yield and concentrations of both ammonium and nitrate forms of N was quadratic. The optimum concentration of ammonium‐N in soil for maximum grain yield gradually decreased with the age of the crop from 54.6 to 63.6 μg g‐1 at 15 DAS to 22.7 to 26 μg g‐1 at 30 DAS. In the case of nitrate‐N its optimum concentration for maximum grain yield increased with age of the crop from 25.1 to 30 μg g‐1 at 15 DAS to 31.6 to 34 at 45 DAS and it decreased thereafter.
The Effect of Damage to the Root System Caused by Inter‐Row Cultivation on Growth of Maize
Authors: van der Werf H. M. G. , Tollenaar M.
Published: April 2008

Inter‐row cultivation of a weed‐free maize crop may affect yield. This study was done to establish whether inter‐row cultivation damages crop roots in maize (Zea mays L.) and to assess the effect of root pruning on growth and yield. In 1986 and 1987 inter‐row cultivation and root cutting treatments were applied to field‐grown maize crops in three experiments. Growth analysis revealed that the crop responded differently to the treatments in each trial. Measuring xylem exudate shortly after application of the treatments as an estimator of root damage proved useful in explaining crop responses. In one experiment no root damage occurred and crop growth was not affected. When root damage did occur (in the other two experiments), dry matter yield 3 weeks after treatments was found to be related to xylem exudate yield shortly after the treatments. A reduction of xylem exudate of 1 g/h per plant was associated with a reduction of 360 to 700 kg/ha in whole plant dry matter. In one of these experiments the effect of root damage in whole plant dry matter yield remained until final harvest; in the other experiment all treatments had similar yields at final harvest.
Translocation of N in Pods of Oilseed Rape during Siliqua Developing
Authors: Zhang Q. Z. , Xi H. F. , Kullmann A. , Geisler G.
Published: April 2008

A pot experiment was conducted to investigate the translocation of N in pods during siliqua developing of oilseed rape using 15N‐urea. The 15N was applied on the surface of pods at lower stem in three periods after flowering. At maturity the hulls and seeds of pods at different parts of plants were subjected to analyse N content and 15N abundance and calculate recoveries of N applied.

79.1–84.3 % of labelled N applied were recovered from the total pods including 75.3–80.4 % in labelled pods. A great part of the N was translocated in seeds, the later the labelled N application, the more proportion of N in seeds was. Application of MgSO4 combined with urea promoted the uptake and translocation of N, but not at a significant level.
Polynomial Functional Models to Simulate Crop Growth in Maize (Zea mays L.) Cultivars
Authors: Prasad T. V. Ramachandra , Krishnamurthy K. , Devendra R. , Kailasam C.
Published: April 2008

Polynomial and polynomial exponential models of order one to four were tried to describe crop growth in two maize cultivars viz., Deccan hybrid and Deccan 101 of an agronomic trial conducted at the University of Agricultural Sciences, Bangalore, on alfisols. Relative growth rate (RGR) of classical and functional methods was compared. Models performance was assessed based on r2, χ2 residuals sum of squares (RSS), root mean standard deviation (RMSD) and presence or absence of heteroscedasticity in models' predictions. In the cultivars, polynomials of order three and four in Deccan hybrid and cubic polynomial in Deccan 101 simulated dry matter production (DMP) by 99.5 % and showed good distribution of error variance over the observed DMP. The RGR from the third and fourth degree polynomials in both the cultivars was comparable to the classical method and explained better during post‐silking period. Polynomial exponentials predicted very low RGR. Between cultivars, Deccan 101 showed higher RGR during 45–80 days after sowing and contributed significantly more to final DMP.