bluuebunny/crossref_metadata_2025 huggingface dataset:
Response of Triticale Grain Yield and Yield Components to Number of Cuttings in a Mediterranean Environment
Authors: Ramos J. M. , Marinetto J. , Del Moral M. B. Garcia , Del Moral L. F. Garcia
Published: April 2008

In six field experiments conducted over 2 years, the effect of one or two cuttings on grain yield of triticale (×Triticosecale Wittmack) were investigated. In addition, the relationships between triticale grain yield its components were analysed.

Grain yield of the uncut plots invariably exceeded the plots with one or two cuttings, regardless of the environment or year. The reductions in grain yield caused by one cutting ranged from 27 % to 60 % under rainfed conditions and 18 % to 20 % under irrigation. With two cuttings the reduction was 45 % to 70 % for rainfed, and 35 % to 48 % for irrigated conditions.

The yield components which most influenced grain yield of triticale under cutting treatment were the number of ears m−2 in all six experiments and the number of grains per ear under rainfed conditions. At the rainfed sites in 1989 cuttings diminished the number of ears m−2 mainly by increasing plant mortality. Nevertheless, at the rainfed sites of 1990 and at the irrigated site of both years, the reduction in the number of ears m−2 with cuttings was due principally to a lower survival of tillers per plant.
Effect of Rooting Pattern on Rice Productivity under Different Water Regimes
Authors: Vijayalakshmi C. , Nagarajan M.
Published: April 2008

Three rice varieties, viz. ADT 31 (drought tolerant) CO 41 (upland) and IR 50 (drought susceptible), were employed to study their rooting patterns under different water regimes. ADT 31 had better root penetration and distribution under water stress situation compared to others. The values on root weight also established a similar trend. Isotopic studies with 32P also provided evidence in this regard wherein the variety ADT 31 showed its adaptiveness to drought. Marginal reduction in plant height, less tiller production and leaf area reductions were noted in ADT 31 and CO 41 under decreasing soil moisture which showed its ability to cope with the water stress situation. Though IR 50 recorded higher grain yield at normal irrigation, a drastic reduction was noted under extreme water deficit. But ADT 31 recorded consistent values in all situations with slight marginal reduction which evidently proved the interdependent nature of rooting pattern and its influence on productivity.
Effect of Defoliation and Deflowering on Post‐Flowering Dry Matter Distribution in Chickpea (Cicer arietinum L)
Authors: Polisetty Chandra R. Raghuveer , Singh D. V.
Published: April 2008

Studies on source‐sink relationship were conducted in two chickpea varieties Cicer arietinum L. namely, Kabuli (L‐550) and Desi (BG‐256). The primary objective of the present study was to assess the influence of source/sink manipulation by defoliation or deflowering or both on dry matter accumulation in different vegetative parts. Seeds were sown in earthen pots containing sandy loam soils. Plants were raised under normal moisture conditions following recommended agronomic practices. In defoliation treatment all the freshly formed leaves were removed from the onset of flowering until harvest. The leaves formed earlier were kept intact. Removal of flower buds from start of flowering until harvest contributed deflowering treatment. Defoliation and deflowering treatment is a combination of both, whereas untreated plants served as control. Significant differences in dry matter distribution and total soluble sugar (TSS) content as a function of source sink manipulation were observed between the varieties. Defoliation treatment preferentially increased more stem dry weight (DW) in L‐550 and more root and nodule dry weight in BG‐256. In both the varieties deflowering treatment resulted in increased leaf and stem DW. This treatment also resulted in increased root and nodule DW in BG‐256, but only nodule DW in L‐550. When defoliation treatment was combined with deflowering, in both the varieties a decrease in DW in leaf and stem and an increase in DW of root and nodule were observed. Total dry matter content increased 2–3‐fold with deflowering in L‐550 but in Bg‐356 there was no significant increase, indicating a possible role of flowers and reproductive organs in dry matter accumulation. Similar results were obtained even with defoliation, which indicates the major role played by leaves formed before flowering in L‐550, and leaves formed after flowering in BG‐256. Thus, this study suggests variation in the functional role of leaves formed before and after flowering.
Nitrate Assimilation and Nitrogen Harvest in Uniculm ‘Gigas’ Wheat (Triticum aestivum L.)
Authors: Abdin M. Z. , Kaim M. S. , Bansal K. C. , Abrol Y. P.
Published: April 2008

Contribution of the upper laminae designated as 7, 8 and 9 (flag), to the total reduced nitrogen was determined by two different methods; integration of nitrate reductase activity over the entire growing season of individual laminae, and laminae removal at ear emergence. The values obtained by these methods were: 20, 14, and 12 %, and 23, 15, 12 %, respectively. The in vivo nitrate reductase activity was relatively higher in the lamina 9, which contributed an extra 8 % towards total reduced nitrogen when the other laminae were removed from the shoot. No such compensatory response was observed when either lamina 7 or 8 was retained.
Growth Analysis Using Classical and Functional Techniques in Relation to Soil Moisture in Mustard
Authors: Mondal R. K. , Paul N. K.
Published: April 2008

A Reid experiment was conducted to study the effect of soil moisture on growth of two mustard cultivars using classical and functional techniques of growth analysis. Two soil moisture levels were irrigated at 10‐day intervals and a rainfed control was included. Total dry matter (TDM), leaf area index (LAI) and leaf area duration (LAD) were significantly increased by irrigation at most of stages of growth. Starting from a lower value, LAI and LAD reached a peak and then gradually declined. Among the growth attributes, crop growth rate (CGR), leaf area ratio (LAR) and leaf weight ratio (LWR) increased significantly under irrigation. Net assimilation rate (NAR) decreased more in the irrigated plants than the rainfed plants at the later stages of growth. LAR and LWR declined throughout with increasing time and plant weight. Seed yield of the irrigated plants was positively correlated with the pre‐flowering LAI and the post‐flowering CGR and NAR. In the rainfed plants, seed yield was positively correlated with LAI and CGR at the post‐flowering stage and negatively with the post‐flowering NAR and pre‐flowering LAR.
Evaluation of Upland Rice (Oryza sativa L.) Genotypes for Intercropping with Pigeon Pea (Cajanus cajan [L.] (Mill sp.))
Authors: Ghauhan J. S. , Singh C. V. , Ghauhan V. S.
Published: April 2008

Eleven upland rice genotypes of varying growth duration and plant stature were evaluated in two cropping systems: monocrop and intercrop, with pigeon pea cv. Upas 120, in order to study the effects of intercropping on rice grain yield and its contributing characteristics during 1990 to 1992 wet seasons. Cropping system and cropping system × genotype interaction effects were significant for yield ha−1, panicle weight, panicles m−2 and spikelet fertility suggesting the need for evaluating and selecting genotypes suitable for intercropping. Rice grain yield reduction in the intercrop ranged from 24.5 % in genotype RR 203‐16 to 54.5 % in genotype Aditya. Panicle weight, total dry matter at flowering as well as at harvest, and harvest index were also reduced. Plant height and panicle weight were positively associated with yield in both systems, however, the yield was positively and significantly correlated with spikelets per panicle and spikelet fertility with the intercropping system. The correlation between cropping systems indicated the possibility of simultaneous improvement for these characteristics in monocropping and intercropping.
Surface Structure of Leaves in Heat Tolerant Plants
Authors: Welker O. A. , Furuya S.
Published: April 2008

The objective of our studies was to investigate the effect of high temperature on cabbage cultivars which were different in heat tolerance in terms of head formation.

We determined whether there were cultivar differences in the properties of epicuticular wax, growth parameters such as leaf number, leaf area and dry weight and whether these factors contribute to head formation under stress.

Four cabbage varieties including the Japanese heat tolerant cultivar Sousyu, were grown in pots at different temperatures in growth chambers.

The stability of the wax differed with the varieties. The wax of Kinsyun melted at a temperature of 32 °C during the day and 29 °C during the night, while the wax of the other varieties was more stable. The density of the tubes, plates or fibrils could be observed by light reflection. For Kinsyun as the low density caused a low reflection, the leaf colour was green, while for Sousyu the leaf colour was blue/white for Akiou, green/ blue and for Braunschweiger, blue.

We conclude that the function of cuticular wax in limiting cuticular transpiration is a product of the architecture of the deposits and the quantity of wax per unit area of leaf surface. Neither the wax structure nor the amount of eight varieties could be correlated with heat tolerance in terms of head formation.
Performance of Rapeseed‐mustard Cultivars under Various Moisture Regimes on the Gangetic Alluvial Plain of West Bengal
Authors: Ghosh R. K. , Bandyopadhyay P. , Mukhopadhyay N.
Published: April 2008

A Field trial was conducted during 1988–89 and 1989–90 at Water Management Research Station, Memari. Bidhan Chandra Krishi Viswavidyalaya, Burdwan, to study the effect of three different irrigation regimes, namely rainfed (I1) (No irrigation), one irrigation (I2) at flowering and two irrigations (I3 at flowering and at sihqua formation stages) on the grain yield and water expenses on four different rapeseed‐mustard cultivars, namely Pusa Bold, Pusa Baroni, Varuna and DIR 247. The variety DIR 247 recorded maximum grain yield (12.1 qha‘) followed by Pusa Baroni (11.8 q ha−1). The variety Varuna showed the lowest water use efficiency (48.1 kg ha−1 cm−1) while DIR 247 showed the maximum value of 57.0 kg ha−1 cm−1. The number of irrigations significantly increased the grain yield. Two irrigations, one at flowering and at siliqua formation stage increased grain yield by 28 % over the rainfed plots. During the crop growth period the actual water expenses among the cultivars in any moisture regime were more or less similar. The interaction between varieties and irrigation levels were, however, not significant.
The Effect of Different Shade Levels on Growth and Tuber Yield of Sweet Potato: I. Plant Development
Authors: Oswald A. , Alkäumper J. , Midmore D. J.
Published: April 2008

The plant development of three sweet potato cultivars under different shade levels was compared during the 1990 and 1991 growth season at two locations in Peru. Deep shade retarded the time of tuber initiation of two cultivars. All shade levels reduced the number of tuber/m2, hence the sink‐size. After the 13th week after planting (WaP) the yield increased very rapidly in full sunlight. Shade reduced these growth rates and the highest increases occurred later in the vegetative period. Therefore, shade generally affected the tuber initiation and formation and eventually tuber yield.

Shoot growth terminated 13 WaP; only in deep shade did the plant top keep growing until harvest and competed permanently for assimilates with the tuber‐sink. The leaf area was hardly affected by shade. The leaf area ratio increased in shade and there was a negative correlation between LAR and tuber and biomass yield. Shade also augmented the specific leaf area by approximately 11 % in 26 % and 42 % light reduction (LR) and up to 20 % in 60 % LR.
Effect of Benzyladenine on Transpiration, Water Potential and its Components in Genotypes of Wheat Contrasting in Drought Tolerance
Authors: Yadava Neelam , Yadav V. K. , Kumar Arvind
Published: April 2008

Drought tolerant and susceptible cultivars of wheat, C‐306 and Kalyan sona, growing under non‐stressed and water‐stressed conditions, were sprayed with benzyladenine (BA) at 70 days after sowing (DAS). Observations recorded at 5, 10, 15, 20 and 25 days after spraying revealed that BA increased the rate of transpiration (TR) in C‐306 under non‐stressed conditions. However, under water stress, the increase was significant only after 5 days of BA spraying. In Kalyan sona BA treatment either decreased TR or did not exhibit significant increase under non‐stressed conditions, but caused significant increase in TR under water stress. The increase in TR was elicited through enhanced stomatal opening. Water potential, osmotic potential and pressure potential of both genotypes decreased on account of water stress. The effect of BA was not perceptible on restoration of leaf water potential (LWP) or its components. The effect of BA was possibly confined to stomatal behaviour and transpiration.
Differential Growth, Nodulation and Nitrogen Fixation Efficiency of Groundnut Cultivars Inoculated with Different Rhizobium Strains
Authors: Shaheen A. , Rahmatullah
Published: April 2008

Growth, nodulation and nitrogen (N) fixation efficiency of Banki (Local) and ICGS‐44 (exotic) varieties of groundnut was significantly (P < 0.05) improved by their inoculation either with NC‐92 or Rudy Patric (R.P.) strains of rhizobium. Nodules did not form without inoculation in plants growing in sterilized sand. Inoculation with R.P. strain of rhizobium resulted in greater shoot growth, N content in shoot and number and weight of nodules in groundnut varieties. The R.P. inoculant increased agronomic efficiency by 112.5 % in Banki and 100 % in ICGS‐44 variety of groundnut. Improvement in N fixation efficiency by inoculation with R.P. inoculant was 334 and 286% in Banki and ICGS‐44 variety, respectively. However, Physiological efficiency was maximum in Banki variety when inoculated with NC‐92 strain of rhizobium.
Nachweis des Strohabbaues über die Stickstoffreisetzung aus 15N‐markiertem Stroh
Authors: Peschke H. , Dölling S.
Published: April 2008

Ten charges of 15N‐labelled straw with different C/N ratios were incubated with lightly loamed sand at 25 °C and 50 % of the maximum water capacity. At the start of the 18‐week incubation, mineral nitrogen was added and the 15Nmin (NH4 and NO3‐N) content was determined six times during the course of the experiment. A slow release of 15N was observed. After 111 days, between 2.5 and 13.0% of the total applied 15N was mineralized. The addition of ammonium sulphate caused an increasing degradation of organic N compounds of the straw material even during the first weeks. Finally, between 6.4 and 33.3 %15N was released. The 15N release only partially shows the straw degradation.
Assessment of Sensitivity to Frost in Ochrus chickling (Lathyrus ochrus (L.) D.C.) by Chlorophyll Fluorescence Analyses
Authors: Ratinam M. , Abd El Moneim A. M. , Saxena M. C.
Published: April 2008

Ochrus chickling (Lathyrus ochrus (L.) D.C.) is a promising feed legume for rain‐fed farming systems in the Mediterranean environments of West Asia and North Africa (WANA) because of its drought tolerance and resistance to broom rape (Orobanche crenata Forsk.). However, it is highly susceptible to cold and improving Its resistance would further improve its adaptation.

The potential of the chlorophyll fluorescence technique in screening for frost sensitivity in seedlings of five Lathyrus ochrus genotypes and one each of Vicia ervilia (L.) Wild and V. sativa L. was assessed by measuring the rate of rise in induced or variable chlorophyll fluorescence of fully developed leaflets after cold hardening in the open and subsequent exposure to freezing. The method differentiated the highly frost‐susceptible L. ochrus genotypes from the more tolerant Vicia species. Testing the technique with nine genotypes of L. ochrus in which the plants were established, cold‐hardened and frost‐stressed under controlled conditions confirmed its sensitivity even to reveal the narrow inter plant differences that generally exist within a cultivar or genotype to frost. It is therefore considered as a useful screening technique for cold/frost tolerance in L. ochrus.
Variations in Sugar Content and Dry Matter Distribution in Roots and their Associations with Frost Tolerance in Certain Forage Legume Species
Authors: Ratinam M. , Abd El Moneim A. M. , Saxena M. C.
Published: April 2008

Enhancement of cold tolerance is an important aspect in breeding forage legumes in view of increasing interest in extending the cultivation of these crops. Three classes of characters — morphological, morpho‐physiological and biochemical — were considered in selection for cold‐tolerance between and within forage legume species under contrasting growing conditions in the field and a plastic house.

Significant correlation was found between cold damage and concentration of sugars m roots of various forage legume species which were grown under field conditions and subjected to natural frost. Both morphological as well as morpho‐physiological characters were related to cold tolerance in Lathyrus ochrus (L.) DC. This indicated that chemical constituents cannot be used as a sole criterion to select for winter‐hardy strains of this species. Root‐shoot ratio showed a consistent relationship with tolerance to cold irrespective of the growing conditions and season. Hence, sugar concentration and root‐shoot ratio are useful characters in testing species found cold tolerant by other methods. The root‐shoot ratio could be used for testing cold tolerance under controlled conditions. The number of primary branches per plant, root weight and shoot weight may be used as morphological characters in selection for cold tolerance in L. ochrus under field conditions.
Brush Clearing on Hill Land Pasture with Sheep and Goats
Authors: Magadlela A. M. , Dabaan M. E. , Bryan W. B. , Prigge E. C. , Skousen J. G. , D'Souza G. E. , Arbogast B. L. , Flores G.
Published: April 2008

Much hill land pasture in the Appalachians is brush infested. Reclamation procedures which are low cost and require low input are needed to provide hill land pasture owners with ways to maintain production on these lands. A field experiment was carried out to evaluate the effectiveness of grazing either sheep (Ovis sp.) or goats (Capra sp.) separately or in combination for brush clearing on hill land pasture. Cutting or herbicide followed by grazing with sheep or goats were also compared. The experiment was conducted on a 1.8 ha powerline right of way for five years (1986 to 1990). Goats reduced brush cover from 45% to just over 15% in one year. Sheep took 3 years to bring about the same result. Cutting and herbicide application increased animal effectiveness, primarily that of sheep, but increased costs. Three year variable costs for brush clearing with goats were estimated at $33 ha‐1, sheep cost was $262 ha‐1, while cutting costs were $133 and herbicide $593 ha‐1. Brush was cleared more cost effectively and rapidly by goats, but at the end of 5 years all treatments reduced brush cover to 2%.
Further Evaluation of the Resistance of Black Barley to Water Stress: Preliminary Assessment for Selecting Drought Resistant Barley
Authors: Yasseen B. T. , Al‐Maamari B. K. S.
Published: April 2008

Some parameters for screening drought resistance in barley were examined during various stages of plant development using two contrasting cultivars (local Iraqi cv. Black and Australian cv. Clipper). These parameters include leaf growth, tiller number, relative water content (RWC), proline accumulation and ionic composition. More pronounced drought resistance in Black was expressed by significantly lower reduction in leaf area, cell and tiller numbers compared with Clipper; proline concentration, RWC and ionic (N, P, K) concentration in expanded leaves, on the other hand, did not clearly distinguish the cultivars. Black was particularly drought tolerant at the post‐flowering stage.
Effect of IAA and GA3 on the Anatomical Characteristics, Straw and Fiber Yield and Quality of Flax
Authors: El‐Shourbagy M. N. , A Bahia , Ghaffar Abdel , El‐Naggar R. A.
Published: April 2008

IAA and GA3 had increased the stem thickness by increasing that of cortex, phloem fibers and xylem. Each had increased straw and fiber yield/plant, but the effect was more pronounced with GA3 than IAA. The percentage of long fibers, strength and fineness increased significantly with GA3. The latter two properties decreased with IAA.
On the Importance of Soil Homogeneity when Evaluating Field Trials
Authors: Becher H. H.
Published: April 2008

The existence of strong heterogeneity of soils on a scale of plots for field trials is demonstrated by a trial for fodder crops on a Lithic Rendoll in Upper Bavaria, Germany. Initial basic (pH, Corg, Ccarb texture) as well as physical (saturated hydraulic conductivity, bulk density, pore size distribution) soil properties vary strongly across a single plot. Due to the great extent of these variations, the effects of preceding and succeeding crops on soil structural properties within a subplot or subsubplot can only be evaluated with high uncertainty. The effect of weather on soil structural properties during the 18 month trial period must also be considered. Therefore, (i) no sampling of the soil at the end of the trial was done, and (ii) surveying the soil before designing field trials is recommended.
Influence of Heat Stress on Growth and Leaf Epicuticular Structure of Cabbages
Authors: WELKER O. A. , FURUYA S.
Published: April 2008

These studies demonstrate that epicuticular wax may effect the water balance of cabbage under high temperature conditions. In ten week old leaves we did not observe that the cristalline structured wax of the variety Kinsyun was reduced as in three week old leaves compared to Sousyu at high day and night temperatures. Neither the wax structure nor the amount of surface wax of eight varieties could be correlated with their ability to build a head. That head formation of the heat tolerant Sousyu stopped at 27/29°C (day/night) suddenly after starting between leaf stage 11 and 15 could not be explained with differences in the optimum of the photosynthesis or water stress.

Growth parameters such as leaf number, length, area and dry weight of additional varieties, Akiou and Braunschweiger, first recommended for summer growing in warm areas and later in a temperate climate, were determined after three month exposure to mean temperature regimes of 27/29, 27/24 and 24/24°C in growth cabins.
Salinity Tolerance of Rice (Oryza sativa L.) with Reference to Endogenous and Exogenous Abscisic Acid
Authors: BOHRA J. S. , DÖRFFLING H. , DÖRFFLING K.
Published: April 2008

Experiments conducted m a phytotron on three rice varieties of different salinity tolerance revealed an increase in the content of endogenous abscisic acid (ABA) with increasing NaCl salinity in IR20 (semi salt‐tolerant), but in Pokkali (salt‐tolerant) and IR28 (salt‐sensitive) the increase in ABA content was marginal. Under sahnity stress, in general, 5 weekly sprayings of ABA (10‐4 mol L‐1) decreased Na and K concentrations in the shoot to the extent of 29.5 % and 3.3 %, respectively. However, ABA application significantly improved the K/Na ratio as well as the chlorophyll fluorescence decrease ratio (Rfd, indicator for potential photosynthetic activity), the number of green leaves per plant and the shoot dry weight. The response of IR20 and IR28 to ABA application was significantly better than that of Pokkali. Increasing salinity caused marked nutrient imbalances, decreased Rfd values and shoot dry weight. The results are discussed in relation to possible mechanism of salinity tolerance.
Einfluß eines Wachstumsregulators auf die ‘Sink’‐Kapazität von Raps (Brassica napus L.)
Authors: Fisahn J. , Höfner W.
Published: April 2008

Influence of a Plant Growth Regulator on the ‘Sink’ Capacity of Oilseed Rape (Brassica napus L.)

A pot experiment was carried out to examine the effect of the plant growth regulator Triapenthenol (RSW) on the apical dominance of oilseed rape and its corresponding effect on the plant's ‘sink’ capacity. RSW's influence on the number of flower primordia, flowers, pods, yield and yield structure of the whole plant and of different fractions of the plant (main shoot, lateral shoots 1–3, lateral shoots >3; 1st, 2nd and 3rd‐order lateral shoots) and its effect on gibberellin content and shoot height was measured.

RSW diminished dominance of the main shoot and of 1st‐order lateral shoots: the initiation of flower primordia was increased to about 34% and 116%, respectively, in fraction lateral shoots higher than 3 and 3rd‐order lateral shoots. Buds developed in a more synchronized pattern leading to a significantly improved number of flowers and pods in fraction lateral shoots higher than 3. Despite an increased number of pods per plant, grain yield remained unchanged because of a decrease in the number of seeds per pod and an unaffected thousand‐kernel weight.

A decreased content of gibberelhn A19 (GA19), GA20, GA1 and GA8 was evident after application of RSW, and a correlation between gibberellin‐content and shoot height was found.

The results of this study suggest that high levels of such GAs, that primarily promote shoot elongation and strengthen the apical dominance within the plant, limit the plant's ‘sink’ capacity. These effects may be due to a gibberellin‐promoted auxin‐synthesis.
Effect of Water Regimes and Moisture Stress at Different Growth Stages on Nodule Dynamics, Nitrogenase Activity and Nitrogen Fixation in Soybean (Glycine max (L.) Merrill)*
Authors: Sridhara S. , Thimmegowda S. , Prasad T. G.
Published: April 2008

The effect of water regimes and soil moisture stress on total nodule number, effective nodule number, nodule dry weight, nitrogenase activity and nitrogen fixation in soybean was studied. The effective nodule number, nodule weight, nitrogenase activity and nitrogen fixation increased due to increase in water regimes from 0.4 to 0.6 Cumulative Pan Evaporation (CPE). The stress during either flowering or pod filling reduced the effective nodule number, nodule weight, nitrogenase activity and nitrogen fixation. The amount of nitrogen fixed was maximum with 0.8 CPE (50.09 kg ha‐1 season‐1) followed by 0.6 CPE (42.08 kg ha‐1 season‐1) and 0.4 CPE (33.04 kg ha‐1 season‐1). The amount of nitrogen fixed was reduced by 17.71 % and 26.39 % due to stress during flowering and pod filling respectively compared to normal irrigation.
Accumulation of Biomass and Nitrogen During Plant Growth in Highly Diverging Genotypes of Winter Wheat
Authors: Bertholdsson N.‐O. , Stoy V.
Published: April 2008

Data are presented on the accumulation of nitrogen and total biomass into wheat plants at different stages in their ontogeny. Five genotypes of highly diverging origin and with widely deviating grain protein contents were cultivated at different nitrogen regimes (ranging between 0 and 150 kg N ha‐1). Growth curves as polynomials were calculated from representative subsamples of plant material collected from each plot at weekly intervals, commencing early in the vegetative stage and ending at complete maturity. Dry weights and nitrogen contents were determined for above‐ground plant parts and for grains, when present, and were expressed per nr ground area. During the first 2 years total green areas were estimated as well and leaf area indices (LAIs) calculated and fitted to polynomials. The results from these trials revealed that the two American high‐protein genotypes Goertzen 5559 and Frontiersman produced distinctly less biomass (mainly carbohydrates) than the Swedish genotypes Folke, Solid, and Lantvete during the later phases of growth. The lower biomass production of the American types after anthesis appeared to be more due to a decreased photosynthetic activity and less to a decrease in green area. It was also found that the American genotypes had a higher efficiency in remobilizing previously produced and stored assimilates than the modern Swedish cultivars Folke and Solid, which were more dependent on current photosynthesis. With respect to uptake of nitrogen into biomass there was very little variation between the genotypes at the early stages of plant life, but later on clear differences developed between the American and Swedish genotypes. Thus the former accumulated considerably less nitrogen than the latter, but since the differences between the two groups were still more pronounced regarding accumulation of biomass the American types exhibited higher concentrations of nitrogen in total biomass towards the end of the growing season. This higher concentration of N seems to indicate an increased relative ability for the American types to take up nitrogen from the soil during the grain filling phase but it is uncertain whether a causal relationship actually exists with the ability to accumulate protein in the grains. Estimates of the efficiency to redistribute nitrogen to the grain did not show any significant differences between the five genotypes and the most probable explanation for the high grain protein values of the American genotypes therefore seems to be their relatively low production of carbohydrates (and biomass). In a subsequent paper results horn a comprehensive field trial concerning grain and straw yields, structural yield components, soil analyses, etc. will be presented which further corroborate these conclusions.
Storage of Non‐structural Carbohydrates in Sweet Sorghum [Sorghum bicolor (L.) Moench.]: Comparison of Sterile and Fertile Lines
Authors: Fortmeier R. , Schubert S.
Published: April 2008

The accumulation of soluble carbohydrates in vegetative parts of sweet sorghum (Sorghum bicolor (L.) Moench.) represents an intermediate reserve pool for grain filling as well as an irreversible storage up to maturity. In order to study the effect of Sterility on soluble sugar accumulation in vegetative parts, two cytoplasmic male sterile (CMS) lines of sweet sorghum were compared with their corresponding fertile mamtainers for non‐structural carbohydrate concentrations in shoots. Plants were harvested at four different physiological stages. The lines showed significant differences in the yield of non‐structural carbohydrates. At maturity, the yields of soluble carbohydrates from vegetative parts of the two sterile lines were 93 % and 43 % higher than the yield of the two corresponding fertile lines. At that stage, sucrose represented about 80 % of total soluble carbohydrates and the higher yield of soluble carbohydrates of sterile lines was mainly due to the higher yield of sucrose. This indicates that the yield of extractable carbohydrates, especially sucrose, in vegetative parts of sweet sorghum could be considerably improved by using sterile lines which are utilized in hybrid production.
Distribution Pattern of Free Proline in Rice (Oryza sativa L.) Grown under Low Light Irradiance
Authors: Singh V. P. , Voleti S. R. , Rao Ch. N.
Published: April 2008

The variation in free proline levels of two rice (Oryza sativa L.) cultivars grown under normal and low light intensities was studied. The aim of the present investigation was to find the distribution pattern of free proline in the whole plant. Free proline levels were determined in Flag leaves, culm and pollen grains, milky, dough and mature grains of Swarnaprabha (SP) and Ratna cultivars. The Flag leaf of Ratna had higher proline levels compared with (SP) under both light levels. Among the parts studied, pollen grains had the maximum free proline content in both the cultivars. Low light irradiance did not alter free proline levels of pollen grains in both the cultivars, indicating that proline could be important for the pollination process. Milky, dough and mature grains had lower proline levels under low light. The varietal, treatment and their interaction was not significant for mature grains of both low light tolerant ‘SP’ and standard Ratna Cultivars. It was indicated that low light stress is unique with regard to free proline.
Effect of Elevated CO2 on the Photosynthesis, Growth and Water Relation of Brassica Species Under Moisture Stress
Authors: Uprety D. C. , Mishra R. S. , Abrol Y. P.
Published: April 2008

An attempt has been made to study the interactive effect of elevated CO2 and moisture stress on photosynthesis, growth and water relations of Brassica species using open top chambers. It was observed that plants responded to elevated CO2 significantly under moisture stress condition mitigating the adverse effects on photosynthesis and growth of Brassica species. Relatively drought susceptible species, viz. B. campestris and B. nigra, responded to elevated CC2 markedly as compared to less sensitive B. carinata and B. juncea plants. The water status of plants significantly improved under elevated CO2 concentration possibly by increasing stomatal resistance and/or by increased root growth.
Influence of Biopost and Organo upon Flue‐cured Tobacco Grown on Semigley I. Leaf Yield and Participation of Particular Tobacco Classes
Authors: BUTORAC A. , BUTORAC J. , MESIĆ M. , TURŠIĆ I. , BAŠIĆ F. , VULETIĆ N. , BERDIN M.
Published: April 2008

Investigations were carried out on semigley in the central River Drava valley (Northern Croatia) with the aim of establishing the fertilizing value of biopost, as a representative of organic fertilizers, and of organo, as a representative of organic‐mineral fertilizers, in comparison with mineral fertilizers and stable manure, the latter two being compared with each other as well regarding the yield and quality of flue‐cured tobacco leaf. Efficiency of the fertilizer types and rates applied was strongly affected by very adverse meteorological conditions, which often showed characteristics of severe drought. Nevertheless, under such conditions and despite the minimum rates applied, biopost and organo had a positive effect on the yield and quality of the flue‐cured tobacco leaf. In all cases, they had an obvious advantage over mineral fertilization, offering distinct possibilities of their application in the growing of flue‐cured tobacco. However, owing to its better fertilizing efficiency, combined organic and mineral fertilization might be justified, certainly also with respect to the economic aspect of the problem. The positive influence of biopost and organo on the higher participation of quality classes of flue‐cured tobacco leaf in comparison with mineral fertilization is indisputable despite the occasionally prevailing effects of fluctuating weather conditions during the investigation period. In other words, harmonic organic, even organic‐mineral, fertilization should be preferred to mineral fertilization alone.
Yields of Dry Matter and Nitrogen in Highly Diverging Genotypes of Winter Wheat in Relation to N‐uptake and N‐utilization
Authors: Bertholdsson N.‐O. , Stoy V.
Published: April 2008

The aim of the investigation was to find out if certain North American genotypes of winter wheat with exceptionally high grain protein concentrations (GPCs) are characterized by an extraordinary ability to take up and/or distribute nitrogen from the soil to the grains. Two of these genotypes were grown in a field trial in southern Sweden together with three ‘normal’ Swedish genotypes (two modern cultivars and one old landrace). They were compared with respect to accumulation of dry matter and nitrogen in both grains and straw when cultivated at three levels of N‐fertilization (0.75 and 150 kg N ha‐1)‐ The results of this trial demonstrated that the yields of above‐ground biomass (BY) and grain (GY) were significantly lower for the American genotypes than for the Swedish ones. Also the nitrogen yields in biomass (NBY) and grain (NGY) were significantly lower in the American types but the difference between the two groups was not so pronounced as with respect to dry matter yields. The American types were thus superior to the Swedish ones in relative ability to take up nitrogen but not in absolute terms. The GPCs of the American wheats were very high also under Swedish growth conditions but a regression analysis of the relation between GPC and GY revealed a very strong negative correlation between these parameters (r = ‐0.95 at 0 N and r= ‐0.99 at 150 N). The correlation between GPC and HI was highly negative, too, (r = ‐0.83 at 0 N and r = 0 89 at 150 N).

The specific ability to take up nitrogen was determined by estimating the changes in soluble soil nitrogen (NO3+ NH4) in the unfertilized plots during the vegetation period. These measurements indicated that the American types were less effective in retrieving nitrogen from the soil than the Swedish ones. The analysis of the soil in the fertilized plots also demonstrated that the American types were slightly inferior to the others in their ability to recover externally applied nitrogen. The efficiency to utilize absorbed N for production of above‐ground and grain biomass was also estimated from the experimental data. The results demonstrated very clearly that the American genotypes exhibited a considerably lower nitrogen utilization efficiency than the Swedish types. Also the efficiency to allocate absorbed nitrogen into the grains (expressed as nitrogen harvest index, NHI) was examined and was found to be nearly identical for all genotypes and almost independent of the level of N fertilization. It is therefore claimed that the results reported in the present communication confirm the conclusions from part I of this investigation, namely that the main reason for the high GPCs in the American genotypes investigated here are their relatively low dry matter production in the grain filling period. This fact does not exclude, however, that other high‐protein genotypes may carry genes which in appropriate crosses can combine high‐yielding ability with an improved GPC.
Changes in Growth, Ions and Metabolites in Two Callus Lines of Vigna radiata which Differ in Salt Tolerance
Authors: Gulati A. , Jaiwal P. K.
Published: April 2008

NaCl‐resistant (selected at 300 mM NaCl) and non‐selected cell lines of Vigna radiata were compared for growth, various ions and metabolites at weekly intervals up to 28 days of culture in the presence or absence of NaCl (0–300 mM). The sale‐resistant line grew significantly better than the non‐selected line at NaCl concentrations higher than 50 mM. The resistant line accumulated significantly more Na+ and maintained higher levels of K+ under NaCl stress than the non‐selected line. Both lines accumulated various metabolites, e.g. protein, proline and soluble amino‐nitrogen under stress, but this accumulation was greater in the non‐selected line than in the resistant one. On the other hand, total content of reducing sugars and sucrose (soluble sugars) was significantly higher in the latter than the former. Moreover, the concentration of soluble sugars in resistant calli was much higher than the other intracellular metabolites. Thus, sugars and ions are likely the major osmoregulants in the resistant line of V. radiata under salt stress.
PIEteR: a Field‐specific Production Model for Sugar‐beet Growing
Authors: Smit A. B. , Struik P. C.
Published: April 2008

PIEteR is a field‐specific production model for sugar‐beet growing. It can provide quantitative information about the technical, economic and environmental consequences of plant density, nitrogen application and harvest date. Its core is a growth model that simulates rates of emergence, development, and root and sugar production, corrected for non‐optimal water availability. Although PIEteR is not yet able to simulate extreme situations correctly, it is a good basis for the further development of a decision‐support system.
Water Use and Yield of Wheat under Unmulched and Mulched Conditions in Laterite Soil of the Indian Sub‐continent
Authors: Zaman A. , Choudhuri S. K.
Published: April 2008

A held experiment was conducted during three winter seasons on West Bengal laterite soil to study the effect of irrigation and paddy straw mulch on water consumption. Water use efficiency and yield of wheat are reported. Both irrigation and mulch increased wheat yield significantly; there was also significant interaction between irrigation and straw mulch application: three irrigations combined with mulch resulted in 21.6 q ha‐1 wheat grain yield compared with 17.5 q ha‐1 for three irrigations without mulch. Mulch consistently increased irrigation response. Both irrigation and mulch increased water consumption and water use efficiency of the wheat crop. To compare the two irrigation treatments, irrigation at crown root initiation followed up by at flowering stage gave higher values of water use efficiency as well as higher grain yield than that of irrigation applied at panicle stage followed by at crown root initiation.
Indirect Determination of Leaf Area Index of Sugar Beet Canopies in Comparison to Direct Measurement
Authors: Röver A. , Koch H.‐J.
Published: April 2008

The determination of the leaf area index of sugar beet canopies by using direct measurement techniques is very laborious. Indirect measurement techniques based on the theory of gap fractions offer a non‐destructive and rapid determination of the leaf area index. In this study the performance of the LAI‐2000 instrument from LI‐COR1 which measures the gap fraction at five zenith angle classes with an upward looking sensor was compared to a direct determination.

A thinning test and two measurement series in sugar beet with different population densities and varied nitrogen application were conducted in 1992 and 1993 at the site of Göttingen. The direct determination of leaf area index was based on a destructive sampling of leaves and measurements with a Delta‐T2 image analysis system (DIAS).

The results of the thinning test and the measurement series in 1992 did not indicate a significant difference between the LAI‐2000 and the direct determination. With correlation coefficients of 0.98 and 0.95 respectively, the relation between the two techniques was very close. The measurement series of 1993 showed a worse correspondence. In general the values of the LAI‐2000 measurements tended to be a bit lower than those of the direct determination. The leaf area index of sugar beet can be determined with sufficient accuracy using the LAI‐2000 instrument if light conditions are favourable and if the measurement procedure is adapted correctly.
Water Sensitive Periods during the Reproductive Growth Phase of Glycine max L. II Establishing Water Stress Sensitivity
Authors: De Bruyn L. P. , Pretorius J. P. , Human J. J.
Published: April 2008

The water sensitivity of soybeans was determined on a day‐to‐day basis from the onset of flowering to physiological maturity by correlating daily leaf water potential values of 50 different soil water regimes with corresponding grain, vegetative and biomass yields. Days, and consecutive days forming periods, during which significant negative correlations were obtained were regarded as water sensitive periods during the reproductive growth phase of the soybean crop.

Water deficits during flowering significantly inhibited vegetative and biomass production but inhibited grain yields only when occurring during early flowering. During pod elongation and seed development the sensitivity of the soybean plant to water stress was present but diminished in time with regard to vegetative and biomass yields. The effect on grain yields was restricted to pod elongation and to later seed development stages. Water stress affected grain yields to a far greater extent than vegetative growth during seed filling and physiological maturity.
The Effect of Chilling Temperature on the Permeability of Membranes to K+, Mg2+, Ca2+ ions and on the Electric Potential of Leaves in the Seedlings of Maize (Zea mays L.)
Authors: Filek M. , Kościelniak J.
Published: April 2008

The relations between the extent of injuries in seedlings caused by a few day‐long exposures to chill (5°C) and the leakage of K+, Mg2+ and Ca2+ ions from the leaves as well as the electric potential in seven maize hybrids, were investigated. The permeability of cells to ions was defined based on their absolute concentration in a water diffusate (Ct) and concentration expressed in relation to the total ion content in the leaves (IL index).

At lowered temperature the hybrids of higher resistance to chilling temperature were characterized by a lower value of the IL index for K+ and Mg2+ ions than the chill‐sensitive hybrids. On the other hand, absolute concentration of the ions (Ct) Mg2+ and Ca2+ leaking from the leaves before chill exposure of the seedlings was positively and highly correlated with the extent of injuries in hybrids caused by 4 day‐long exposures to chill. This observation is evidence that the chill injuries were predetermined through increased cell permeability to the mentioned ions at room temperature.

Changes in the electric potential of leaves in conditions of lowered temperature preceded the injuries of leaves, which became apparent after a longer period of exposure to chill. Thus, as the leakage of Mg2+ and Ca2+ ions occurs, changes in the electric potential may supply early information about the predisposition of the particular maize hybrids to chilling injuries. Leakage measurements of Mg2+ and Ca2+ ions from the leaves at room temperature may find application in the selection of chill‐tolerant maize genotypes.
Water‐Sensitive Periods during the Reproductive Growth Phase of Glycine max L. I. Regression Model for estimating daily leaf water potential
Authors: de Bruyn L. P. , Pretorius J. P. , Human J. J.
Published: April 2008

To establish the exact duration of critical periods for plant water stress during the reproductive growth stage of soybeans it is necessary to draw correlations between daily leaf water potential values and crop growth and yield. Different sets of daily leaf water potential values can be induced by different sets of irrigation applications. It is, however, imperative that water stress values are available for each day over the growing season of a large number of irrigation treatments. Since these values were not available, it was decided to calculate it by establishing a relationship between leaf water potential as determined by potential evapotranspiration and soil water content as well as soil water potential for various layers of the root zone. The most reliable regression formula was found to be:
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Effect of Different Preceding Crops and Crop Rotations on Yield of Winter Oil‐seed Rape (Brassica napus L.)
Authors: Christen O. , Sieling K.
Published: April 2008

To determine the effect of different preceding crops and crop rotations on the grain yield of oil‐seed rape, a long‐term rotation experiment was conducted at the Hohenschulen experimental station in Kiel, NW Germany. Additional factors included the nitrogen fertilization and the fungicide application. The results reported herein are based upon the harvest years 1988 to 1993.

Averaged over the different rotations and husbandry treatments, the grain yields in the 6 experimental years varied between 2.71 t ha−1 and 3.99 t ha−1. In contrast, the effect of the different husbandry treatments was smaller and non significant. Averaged over 6 years, only the fungicide application caused small yield increase of 0.2 t ha−1.

The highest grain yields of 3.77 t ha−1 or 3.65 t ha−1 occurred when oil‐seed rape was directly following peas. Low yields between 3.15 tha−1 and 3.33 tha−1 were obtained when oil‐seed rape was grown after oilseed rape. The lowest grain yield of 3.13 t ha−1 was produced with oil‐seed rape grown in monoculture only. In rotations with oil‐seed rape following a preceding cereal crop (wheat or barley), the grain yields averaged between 3.22 tha−1 in a two course rotation and up to 3.44 tha−1 in a four course rotation. In general, the yields of oil‐seed rape increase with the length of the rotation and the length of the break between two oilseed rape crops. The yield component number of seeds per m2 was affected by the previous cropping accordingly, whereas the thousand seed weight did not respond to the cropping history.

Based upon disease assessments in the first years of this experiment, we argue that an increase in the incidence of fungal diseases has considerably contributed to the yield decrease of oil‐seed rape in short rotations.