bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Note on the Skewness of the Frequency Distribution of Harvest Indices with an Application to Winter Oilseed Rape (Brassica napus L.)
Authors: Hühn M. 
Published: April 2008

AbstractBased on well‐known statistical approximations for the mean, variance, and for the third moment about zero of the ratio of two random variables, a general expression has been derived for the skewness of the distribution of harvest indices. The skewness of the distribution of harvest indices depends on three parameters: coefficients of variation for the two component traits and their correlation. Conclusions for the sign of this skewness are discussed. Finally, the theoretical results and conclusions have been checked and applied to an experimental data set of winter oilseed rape. The agreement between expected and observed skewness is extraordinary good.
Pearl Millet Phenology and Growth in Relation to Thermal Time under Arid Environment
Authors: Singh R. S. , Joshi N. L. , Singh H. P. 
Published: April 2008

AbstractPearl millet (Pennisetum glaucum L.R.Br.) hybrid MH 179 was grown under two moisture regimes viz., optimal moisture and rainfed conditions. The field experiment was continued for three consecutive rainy seasons to quantify the pearl millet development with thermal time. The possible influence of variation in natural sowing date on the relationships between crop development and thermal time have been described. At cardinal temperatures of 10°C (base temperature below which pearl millet development ceases), 33°C (optimal temperature for development) and 45°C (maximum temperature at and above which no development takes place), the crop required 1490–1794°Cd thermal time to reach physiological maturity. The thermal time requirement for different developmental stages was influenced by the sowing time and moisture availability during the growing season of the crop.The leaf tip appearance on the main shoot of pearl millet in relation to thermal time was almost linear under both moisture conditions requiring about 44–50°Cd ± 2.6 °Cd leaf−1, till the appearance of the flag (last) leaf. However, leaf tip appearance on primary tillers was slightly slower and required 53‐58°Cd ± 4.7°Cd for each new leaf. Appearance of first primary tiller was later (at 320°Cd after emergence) under the rainfed condition as compared to the crop under the optimal moisture (at 250°Cd).Thereafter, the tiller appearance in relation to thermal time under both moisture conditions was at a linear rate of about 53‐56°Cd ± 9.5°Cd tiller−1.Effect of microclimatic variations, canopy temperature, radiation and photoperiod on the phenology‐thermal time relationships have been discussed under both the moisture conditions.
Yield and Resource Use Optimization in Late Transplanted Mint (Mentha arvensis) under Subtropical Conditions
Authors: Ram Muni , Kumar Sushil 
Published: April 2008

AbstractA field experiment was conducted during 1994 and 1995 at Lucknow (26.5°N, 80.5°E, 120 m above mean sea level) to optimize planting density and fertilizer‐N application for high essential oil yield of late transplanted mint (Mentha arvensis). The treatments studied were 2.5, 2.0 and 1.66 × 105 mint seedlings ha−1 and 0, 80, 160 and 240 kg N ha−1. Under 3 months delayed planting conditions using 2‐month‐old seedlings, the high planting density of 2.5 × 105 plants ha−1combined with 160 kg N ha−1 gave significantly higher herb and essential oil yields compared with those of lower planting densities (2 and 1.66 × 105 plants ha−1) and all other rates of N application. It is demonstrated that a transplanted mini crop, yielding essential oil at a level of 164 kg ha−1, is feasible after the harvest of rabi cereal, oil seed or legume crops in the north Indian plains.
Prediction of Various Effects of Harvest Date in Sugar Beet Growing
Authors: Smit A. B. , Struik P. C. , van Niejenhuis J. H. 
Published: April 2008

AbstractOne crucial decision in sugar beet growing is determining harvest date. This paper focuses on some aspects associated with harvest date which have to be included in a decision support system for sugar beet growing.Firstly, a module was created for dirt and crown tare, mainly based on lutum (or clay) and soil moisture contents. An independent test of the module showed poor results, because fine tuning of harvest machinery has an overriding effect. Secondly, the variation in weather conditions during autumn in Wageningen over a period of 38 years was analysed. The ranges of future root and sugar production appeared to be so wide that early predictions of the day on which the sugar quota are exceeded will not be very reliable. Thirdly, risks of severe frost or heavy rainfall in autumn were assessed, based on the same 38 year data set. The risk of frost damage to unharvested beets proved to be negligible when the crop was harvested before November 10, as advised by the sugar industry.The work described in this study makes the model PIEteR (a field specific bio‐economic production model for sugar beet, developed for decision support at field and farm level) more applicable by using its potential to analyse the effects of different years and quota options.
Chlorophyll and Proline as Affected by Moisture Stress in Young and Mature Leaf Tissues of Brassica carinata Hybrids and Their Parents
Authors: Voleti S. R. , Singh V. P. , Uprety D. C. 
Published: April 2008

AbstractChlorophyll reduction and proline accumulation under moisture stress at three different growth stages in young and mature leaf tissues of B. carinata hybrids of reciprocal origin and their parents was studied. Greater chlorophyll reduction was observed in mature leaves at flowering stage, whereas proline accumulated significantly in young leaves at pre‐flowering stage. The chlorophyll and proline contents per se in hybrids was higher so as their reduction and accumulation compared to their parents. Maternal influence was apparent for these two characters in Brassicas.
Drought Stress Effects on Seed Yield, Yield Attributes, Growth, Cell Membrane Stability and Gas Exchange of Synthesized Brassica napus L.
Authors: Hashem Abul , Amin Majumdar M. N. , Hamid Abdul , Hossain M. M. 
Published: April 2008

AbstractDrought stress effects on leaf gas exchange, cell membrane stability, seed yield and yield attributes of synthesized Brassica napus L. cv. Bangla kale and Bangla cabbage were compared. Drought stress treatments were imposed at early vegetative, late vegetative and flowering stages by withholding watering. Bangla cabbage produced greater pods/plant, larger seed size, greater total dry matter/plant, seeds/pot, and 17% greater yield than Bangla kale. The seed yield in plants stressed at early vegetative, late vegetative and flowering stages were 59, 74, 88% lower respectively, than watered plants. Drought stress reduced leaf photosynthesis by 67 to 97%. Bangla cabbage had 68% greater photosynthesis and 56% greater stomatal conductance than Bangla kale under stress at flowering stage. Leaf temperature was 1 to 2°C higher in stressed plants than watered plants. The cell membrane stability (CMS) increased up to 83% at flowering stage under stress compared to 21% under watered conditions. Although Bangla cabbage had high seed yield, yield attributes and photosynthesis under stressed conditions at flowering stage, its CMS values were lower than those of Bangla kale.
The Role of Phenolics and Peroxidase in Resistance to Alternaria triticina in Bread Wheat (Triticum aestivum L.)
Authors: Tyagi M. , Kayastha Arvind M. , Sinha B. 
Published: April 2008

AbstractTotal phenolic content in eight diverse wheat lines showed that PF‐70354 YACO'S’ had the highest (802.90 ± 1.35 μg g−1 fresh weight) and Agra Local possessed the lowest amount (684.72 ± 5.28 μg g−1 fresh weight). However, for further experiments two lines namely, ACC‐8226 and MP‐845, with contrasting disease scores under field trials were assessed. Pre‐infectional levels of total phenolics and peroxidase activity were higher in ACC‐8226 than in MP‐845. Furthermore, the amount of phenolics and peroxidase activity in each case increased after inoculation. The post‐infectional levels of phenolics and peroxidase were again higher in ACC‐8226 than in MP‐845. The peroxidase activity decreased with age in both the varieties, with very little peroxidase activity after 35th day. However, the amount of phenolics started to decrease with the progress of disease and age in MP‐845, whereas in ACC‐8226 an elevated level of it was maintained. Our findings not only support that ACC‐8226 is the resistant and MP‐845 is the susceptible variety but also provide important biochemical parameters for plant breeders to authentically identify potential breeding material and plan effective breeding strategies using these tools.
High‐temperature Effects on Germination and Viability of Weed Seeds in Soil
Authors: Arora A. , Yaduraju N. T. 
Published: April 2008

AbstractThe control of weeds by solar heating of the soil using transparent polyethylene (PE) sheets was studied in the field during the summers of 1994 and 1995. The maximum soil temperature under plastic cover at 5 cm depth averaged 53°C. At 5 cm soil depth, solarization increased temperature by about 9°C. In the non‐solarized soils, such high‐temperature days were fewer. A temperature of 55°C at 5 cm soil depths was recorded both in irrigated and non‐irrigated mulched soils. However, mulched soil recorded 70% of the treatment period compared with 43% in unirrigated and mulched soils. Lower depths of 10 and 15 cm did not attain a temperature 55°C or 60°C on any day during the experimental period.Solarization treatment with PE sheets significantly increased NO−3—N and NH+4—N in comparison with non‐solarized plots. While uncovered plots showed significant increase in available phosphorus and marginally increased in potassium and electrical conductivity. Organic carbon content and pH did not vary under different treatments.PE mulching for 30 days significantly reduced the number of weed seeds, specifically Avena fatua L. and Phalaris minor Retz., while Trianthema monogyna Linn, and Asphodelus tenuifolius Cav. were not affected much in comparison with the former. Melilotus indica (L.) All, was not at all affected by the solarization treatment studied. The solarization reduction index (SRI) was calculated for each weed species studied and it was concluded that weeds having a low SRI can be controlled more effectively than weeds with high SRI values. The heating effect from solarization decreased significantly with soil depth. The 30 days’ soil solarization treatment in moist soil was more effective than the 10 and 20 days’ heating treatment in moist and dry soils for weed control.
Effect of Mulch and Irrigation Water Amounts on Soil Evaporation and Transpiration
Authors: Abu‐Awwad A. M. 
Published: April 2008

AbstractSoil evaporation, transpiration, evapotranspiration, and yield of pepper as affected by mulch and five amounts of irrigation water were studied in greenhouse pot experiments during 1996 (March 26–July 13). Five different amounts of irrigation water were imposed on covered and open soil surface clay loam soil in five replicates. Water losses by evaporation and/or transpiration were measured daily by weighing. Irrigation water was applied once weekly. The amount of irrigation water added to each treatment was determined from the differences in weights.Covering soil surface reduced the required amount of irrigation water. With deficit (under) irrigation, the reduction in applied irrigation water was about 14%. and increased to 29 % with excess (over) irrigation. Transpiration in covered soil surface treatments were higher than transpiration in open soil surface treatments with limited irrigation water applied, With limited (deficit) irrigation, increasing irrigation water applied decreased the percentage of soil evaporation and the contribution of soil evaporation to crop evapotranspiration. With excess irrigation, increasing water applied increased the percentage of soil evaporation and its contribution to the total evapotranspiration. Soil evaporation reduced pepper yield significantly, and this might be owing to the reduction in the available soil water associated with limited‐to‐complete irrigation.
Differential Response of Two Wheat Genotypes to Nitrogen Supply. II. Mesophyll Cell Characteristics and Photosynthesis of Laminae at Full Expansion
Authors: Sivasankark A. , Lakkineni K. C. , Jain Vanita , Kumar P. A. , Abrol Y. P. 
Published: April 2008

AbstractTwo wheat genotypes, viz. Uniculm ‘Gigas’ (V1) and Kalyansona (V2) were raised to maturity under two levels of nitrogen supply @ 30 (N1) and 120 (N2) kg ha−1, under pot culture conditions. Laminae numbering 1 to 8 on the shoot were examined for area, net photosynthetic rate (Pn) and mesophyll cell characteristics, at full expansion. N1 resulted in greater reduction in the area of upper laminae in V1 than in V2. The flag and penultimate laminae maintained similar Pn rates at both N levels in V1 despite a large reduction in area at N1. However, V2 exhibited about 25% reduction in Pn rates of the flag laminae at N1 as compared with N2. Mesophyll cell number per unit area gradually increased with laminae order in the genotypes. The greater number of mesophyll cells in the upper laminae was essentially due to a reduction in cell size and surface area as a result of low N availability. The large differences in laminae size due to N treatments, particularly in V1, are attributed to mesophyll cell numbers. However, the maintenance of Pn rates in V1, even at low N supply, is a possible outcome of higher activity of the mesophyll cell constituents in this genotype.
Physiological Effects of Winter Rape (Brassica napus var. oleifera) Prehardening to Frost. II. Growth, Energy Partitioning and Water Status during Cold Acclimation
Authors: Rapacz M. 
Published: April 2008

AbstractPrehardening of winter rape, i.e. its early growth in a reduced day temperature (+12°C) from emergence to the beginning of cold acclimation at chilling temperatures (the 1st stage of cold acclimation), has a beneficial influence on frost resistance. In earlier studies it has been demonstrated that during prehardening, plants formed leaf rosettes and increased the photosynthetic efficiency at chilling temperatures. In the present study investigations were carried out on the effect of prehardening on the growth rate of the plants during the 1st stage of cold acclimation, and the progress of selected physiological processes occurring during this stage and resulting in increased frost resistance. It has been demonstrated that a greater inflow of photoassimilates during the 1st stage of cold acclimation results in greater increments of the dry mass of prehardened plants. These plants show also a distinct inhibition both of the elongation growth and the rate of expanding new leaves. The acquired energy is thus spent to a greater extent on the processes associated with increasing frost resistance, and not on growth. In prehardened seedlings, during the 1st stage of cold acclimation, there have been observed in leaves a higher rate of both water content decrease and drop in the osmotic potential of the cell sap and water potential in the tissues. Also an increased accumulation of soluble sugars and free proline was noticed. However, the beginning of these processes was not observed during the prehardening period. Prehardening stimulated the effectiveness of the 1st stage indirectly through changes leading to the increased amount of available energy and enabling the utilisation of the greater part of acquired energy in the cold acclimation process.
Effect of 1‐Naphthaleneacetic Acid Concentrations and the Number of its Applications on the Yield Components, Yield and Fibre Properties of Egyptian Cotton (Gossypium barbadense L.)
Authors: Sawan Z. M. , Sakr R. A. 
Published: April 2008

AbstractField experiments were performed in two successive seasons at the Experimental Station, Faculty of Agriculture, Cairo University, Giza, Egypt, on the Egyptian cotton cultivar Giza 75 (Gossypium barbadense L.). Cotton plants were sprayed with the growth regulator 1‐naphthaleneace acid (NAA) once (at 90 days), or twice (at 90 and 105 days) or thrice (90, 105 and 120 days) after sowing, during the square initiation and boiling stage at the concentrations of 5, 10, 15, 20 or 25 p.p.m. The volume of solution was the same for all treatments. 9601 ha−1. The control plants were sprayed with water only. The effect of the previous treatments on yield components, cotton yield and fibre properties was studied.The application of NAA increased the number of opened bolls plant−1, boll weight, seed index, seed cotton yield plant−1 and seed cotton and lint yields ha−1. The most significant effects were obtained with the 15 and 20 p.p.m. concentrations. Lint percentage, fibre length parameters and micronaire value were not significantly affected by NAA. Flat bundle strength was significantly affected by NAA but with no definite trend. The application of NAA twice or thrice tended to give the best results on yield components and cotton yield compared with one application. The results of this study suggested that 20 p.p.m. of NAA gave the best figures when applied twice on the Egyptian cotton plants.
Effect of Branch Direction's Arrangement on Soybean Yield and Yield Components
Authors: Asanome N. , Ikeda T. 
Published: April 2008

AbstractUseful light interception during reproductive stages is very important for soybean (Glycine max (L.) Merr.) dry matter production. The objective of this experiment was to investigate the light utilization in the canopy for yield, and its components in the case of arranging branch direction to row direction with flat type (1/2 phyllotaxy) soybean. The field study was conducted in the field at Niigata University on a loamy sand soil at 25, 16 and 9 plants m−2 in 1994, 1995 and 1996, using cultivar ‘Miyagishirome’ (Maturity Group VII or VIII, phyllotaxy 1/2; branches develop flatly) with treatments so that branches developed at right angles direction (Type R) and in a parallel direction (Type P) to the direction of the row.Total dry weight (TDW) was greater in Type R than in Type P. A higher leaf area index (LAI) was shown in Type R than in Type P in each plant density among the three years. More light penetrated into the canopy in Type R than in Type P. Higher TDW and LAI were produced by effective light interception at the canopy of Type R.Yield and its components were greater in higher than lower density and tended to be greater in Type R than in Type P. Increased yield depend on seed, pod and node number m−2. The increase of yield components in Type R was suggested to be due to favorable light condition in the canopy, compared with Type P.
Does Salt Tolerance Vary in a Potential Oil‐Seed Crop Brassica carinata at Different Growth Stages?
Authors: Ashraf M. , Sharif R. 
Published: April 2008

AbstractThe salt tolerance of two salt‐tolerant (C90‐1191 and P5/80) and two salt‐sensitive (C90‐1115 and 77–321) lines of Ethiopian mustard (Brassica carinata) (selected on the basis of their performance in germinating ability and seedling growth in a screening experiment) was assessed at the adult stage under glasshouse conditions to evaluate the consistency of salt tolerance at different growth stages of plant life cycle. No difference in response of all four lines differing in salt tolerance was found to varying concentrations of NaCl in the growth medium, although the latter two lines were slightly better than the former two in shoot dry mass, seed yield or yield components. The relatively good growth of the lines C90‐1115 and 77‐321 at the adult stage can be related to their lower accumulation of Na, Cl and Ca in their leaves. K/Na ratios, Ca/Na ratios, K versus Na selectivity, and Ca versus Na selectivity did not prove to be successful criteria in discriminating the lines differing in degree of salt tolerance. In conclusion, salt tolerance in B. carinata varies with the change in stage of its life cycle. Thus selection based at one particular stage may not produce individuals tolerant at all growth stages.
Effects of Temperature and Photoperiod on Vegetative and Reproductive Growth of Groundnut (Arachis hypogaea L.)*
Authors: Nigam S. N. , Nageswara Rao R. C. , Wynne J. C. 
Published: April 2008

AbstractEffects of temperature × photoperiod interaction on vegetative and reproductive growth were examined in three selected groundnut genotypes by growing them in controlled‐environment growth chambers with three temperature regimes (22/18, 26/22, and 30/26°C, day/night) under long (12 h, long day), and short (9 h, short day) photoperiods.The effect of photoperiod on the total dry‐matter production (TDM) was significant with the genotypes producing 32–72% greater dry matter under LD than SD. Temperature × genotype interaction effects were significant, with the dry‐matter production being greatest at 26/22°C and least at 30/26°C and 22/18°C in two of the three genotypes.Leaf area (LA) was greater under LD than SD at all temperature regimes. LA accounted for 76% of the variation in shoot + root dry weight (R2= 0.76, P < 0.01). A lack of relationship between LA and pod weight or pod numbers suggested that the pod development is controlled by factors other than carbon assimilation.The temperature × photoperiod interaction was significant for root growth, with the root weight being maximal and photoperiod effects being minimal at 22/18°C, while at 26/22°C, root weight declined and photoperiod effects became prominent. Low temperature (22/18°C) affected the reproductive development by reducing the proportion of reproductive nodes in total (vegetative + reproductive) nodes. The conversion of pegs into pods, as indicated by pod to peg ratio (PPR), was lower in LD than in SD conditions. Results suggested that the PPR could be used as an indicator of genotypic sensitivity to photoperiod in groundnut.
Estimation and Partitioning of Nitrogen Fixed by Soybean in Mediterranean Climates
Authors: Koutroubas S. D. , Papakosta D. K. , Gagianas A. A. , Papanikolaou E. P. 
Published: April 2008

AbstractA field study was conducted to estimate the nitrogen fixation by soybean [Glycine max (L.) Merr.], using the A‐value and the N‐difference methods, and to examine the N partitioning within the plant. The cultivar Clark and its non‐nodulating isoline (as reference crop) were grown in a silty clay (Typic Xerothent) soil, in 1991 and 1992. 15N‐Labelled fertilizer was surface applied in solution, at rates of 20 and 100 kg N ha−1 to the nodulating and non‐nodulating soybean, respectively. Plant samples were taken at full bloom (R2), beginning of seed growth (R5) and physiological maturity (R7). There was little nitrogen fixation at the early growth stages but it increased rapidly during the seed filling period. At R7 nitrogen fixed was estimated by the A‐value method as 155 kg N ha‐1 in 1991 and as 240 kg N ha−1 in 1992. The corresponding estimates by the N‐difference method were significantly smaller. The seeds had a higher, and the vegetative parts smaller, proportion of fixed nitrogen compared to the whole plant. During the seed filling period, the translocation efficiency for fixed nitrogen was greater (93 % in 1991 and 85 % in 1992) compared to the N derived from soil (75 and 56 %, respectively). It was estimated that, after the harvest of pods, the soil was depleted by a net amount of 121 kg N ha−1 in 1991 and 90 kg N ha−1 in 1992.