bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment of Upland Rice Rooting Depth: Does the Herbicide Injection Technique Work?
Authors: Trebuil G. K , Courtois B. , Herrera W.
Published: April 2008

Water stress is a major constraint to upland rice production. Plants with deep root systems are needed to increase water uptake. For varietal screening or for field diagnosis, breeders and agronomists need methods to monitor rice rooting depth. We assessed a simple, manual technique based on the injection of herbicide at a chosen soil depth using long needles mounted on a veterinary syringe. The time of appearance of herbicide phototoxicity symptoms in the leaves of four rice genotypes with contrasting rooting systems was monitored in the glasshouse and field ‐experiments. Three herbicides (atrazin, diuron and metribuzin) were tested. Metribuzin was selected as the reference herbicide as it consistently induced distinct leaf phototoxicity symptoms 4 days after its application, regardless of the genotype tested. Through the injection of metribuzin at different depths, significant differences in he number of plants affected by the herbicide were detected under field conditions between the extreme genotypes. The ranking of genotypes obtained in the glasshouse and field experiments was consistent with what is known about their respective rooting patterns. However, risks of herbicide leakage above the treated zone reduce the reliability of the technique and precautions were necessary‐ to avoid them. Following the precautions increased he time needed to treat one hill to about 5min, which limits the field of application of the manual technique. Moreover, metribuzin remained present at levels toxic to rice seedlings 7 months after being injected into the soil, in spite of its fast downward mobility and degradation rate. This long residual effect might cause environmental concern.
Effect of Plant Spacing and Nitrogen Levels on Growth, Herb and Oil Yields of Lemongrass (Cymbopogon flexuosus (Steud.) Wats. var. I cauvery)
Authors: Singh M. , Shivaraj B. , Sridhara S.
Published: April 2008

A field experiment was conducted for 2 years during 1991–93 at the Central Institute of Medicinal and Aromatic plants, Bangalore, India to study the effect of plant spacings (60 × 60, 60 × 45, 60 × 30 and 45 × 45 cm) and nitrogen levels (0, 50, 100 and 150 kg N ha−1 year−1) on growth, herb and oil yield of lemongrass. A closer plant spacing of 45 × 45 cm resulted in higher herb and oil yields compared to wider spacing of 60 × 60 cm. Application of 150 kg N ha−1 year−1 resulted in higher herb and oil yields. Higher nitrogen applications also increased the plant height and number of tillers per clump. The oil content and quality‐was not influenced by spacing and nitrogen levels.
Relationship Between Leaf Nitrogen and Photosynthetic Characteristics in Brassica juncea and B. campestris
Authors: Suresh K. , Lakkineni K. C. , Nair T. V. R.
Published: April 2008

The relationship between leaf nitrogen content (N) versus photosynthetic rate (PN) and other associated parameters was examined in Brassica juncea, cv. Pusa Bold and B campestris, cv. Pusa Kalyani. Leaf N, specific leaf weight (SLW), leaf area and PN were significantly higher in B. juncea, while the chlorophyll content was significantly lower compared to Brassica campestris. A significant positive correlation was obtained between leaf N content and photosynthetic rate in both species. Similarly, SLW was also positively related with leaf N content, Brassica juncea showed higher photosynthetic nitrogen use efficiency (PNUE) than B campestris. Leaf N and PNUE were negatively associated. This was attributed to a low investment of N in photosynthesis related reactions and/or partitioning of N towards compounds functionally unrelated to photosynthesis. This attribution is further supported by the negative relationship obtained between SLW and PNUE.
Drying and Storage Method to Prolong Seed Viability and Seedling Vigour of Rabi‐summer‐produced Groundnut
Authors: Nautiyal P. C , Ravindra V.
Published: April 2008

Rabi‐summer‐produced (dry season, February–May) groundnut (Arachis hypogaea L.) cv. GG 2 was dried using three different methods, viz. windrow (W), windrow‐shade (WS) and DOR (Directorate of Oilseeds Research) methods and stored in polyethylene lined gunny bags with or without desiccant (CaCl2 or silica gel, 10gkg−1 pods). The seeds were analysed for the retentation of seed viability, seedling vigour, membrane integrity and Held emergence during storage, and crop stand and pod yield after 12 months of storage. The drying and storage method significantly affected the getminability, seedling vigour and field emergence. Both root length and seedling biomass were adversely affected due to windrow drying (W) The quick loss of viability in the W treatment was associated with an increase in electrical conductivity of the seed leachate. The retention of higher seed viabiliry and vigour in the seeds dried by DOR method and stored with CaCl2 (DOR C) was due to lower drying remperarures and lower pod moisture during the initial storage period. The DOR C method was found to be an effective drying and storage method for retaining acceptable seed viability and vigour till the following rabi‐summer sowing of groundnut.
Development of a New Multifoliate Strain of Berseem Clover (Tricolium alexandrinum L.) in Egypt
Authors: Bakiheit Bahy R.
Published: April 2008

The aim of this work was to obtain mukifoiiare types of berseem clover with a great proportion of the leaf weight and increased plant weight. Thereby research an berseem clover over a 10 year period resulted in the transfer of the multicare gene(s) from a mutant plant of the monocut Fahl culrivar which possess such trait to the muiticut trifoliate culrivar Meskawi by crossing between them. A multicut multifoliate strain was developed after rune generations of selection.

The multsfoliate strain gave significantly higher dry forage yield than commercial cultivate Giza 10, Sakha 4, Giza 15, Helaly and Giza 6 by 22.1, 22.5, 24,8, 29.9 and 36.7%, respectively, in the first cut. On the other hand, the moltifoliate strain gave higher seasonal protein yield than cultivars, i.e. Helaly, Giza 10, and Giza 6 by 7.0,10.1, and 121 %, respectively.

The leaves/stems rario trait averaged over cuts was 18.3 % higher than for the five commercial trifoliate cultivars. Therefore, this multifoliate muiricut strain could be useful for forage especially before sowing cotton or other early summer crops. In addition to that, it could he used as a genetic marker for berseem breeders.
Root Growth of a Salt Susceptible and a Salt Resistant Rice (Oryza sativa L.) During Seedling Establishment Under NaCl Salinity
Authors: Misra A. N. , Sahu S. M. , Meera I. , Mohapatra P. , Das N. , Misra M.
Published: April 2008

The salt susceptible rice (Oryza sativa L.) cv. Jaya and salt resistant cv. Damodar seed germination and seedling growth rates were studied in laboratory and field conditions. The effect of salinity on seed germination, shoot and root length, seedling vigour index (SVI) and increase in the root: shoot length ratio in the laboratory was relatively more in cv. Jaya than in cv. Damodar. The relative susceptibility to salinity was more in cv. Jaya than in cv. Damodar in the field also. However, their responses varied with growth period. The root: shoot length and fresh and dry weight ratios increased with salinity at 15 days in cv. Jaya. The root: shoot fresh and dry weight ratio decreased with salinity at 15 days in cv. Damodar. However, the root: shoot fresh weight ratio decreased with salinity at 25 days in the susceptible cv. Jaya. The root and shoot length fresh and dry weight of cv. Damodar was enhanced at 0.5% (w/v) NaCl treatment compared to the control seedlings at 25 days. SVI in cv. Jaya decreased with salinity in the laboratory and field conditions. SVI in cv. Damodar, SVI showed little change at 15 days but decreased with salinity of 1–3% NaCl with an enhancement at 0.5% NaCl level in the laboratory and at 25 days in field conditions.
Relationship Between Ion Accumulation and Growth in Two Spring Wheat Lines Differing in Salt Tolerance at Different Growth Stages
Authors: Ashraf M. , Khanum Aasiya
Published: April 2008

A salt‐tolerant line, S24, of spring wheat was compared with a salt‐sensitive line, Yecora Rojo, in sand cultures at four different growth stages, i.e. germination, seedling, tillering and booting, under greenhouse conditions. The NaCl treatments used were 0 or 125 mol m−3 in full strength Hoagland's nutrient solution. S24 exceeded Yecora Rojo in biomass or grain yield at the tillering and booting stages, but these lines did not differ at the initial growth stages, i.e. germination and seedling. The growth performance of the two lines at different growth stages was positively related to the pattern of accumulation of cations and anions. The superiority of S24 to Yecora Rojo at the two later growth stages was related to its relatively low accumulation of Na+ or Cl− and high accumulation of K+ in leaves. The former line also maintained higher leaf K/Na ratios, Ca/Na ratios, K versus Na selectivities and Ca versus Na selectivities than the latter particularly at the tillering and booting stages. Salt tolerance in spring wheat, in this study, is found to be age‐dependent. The booting stage has been found as one of the most appropriate growth stages where maximum differentiation in salt‐tolerant and salt‐sensitive lines occurred. As is evident from previous studies with spring wheat, in the present study there is a positive correlation between partial exclusion of Na+ or Cl−1 from the tissues and maintenance of high tissue K/Na and Ca/Na ratios, and K versus Na and Ca versus Na selectivities, and salt tolerance of this crop.
Effect of Foliar Ethanol Application on Septoria Leaf Blotch in Spring Wheat (Triticum aestivitm L.)
Authors: Peltonen S.
Published: April 2008

Foliar applications of alcohols have been reported to have remarkable benefits on yields of several crops. The toxifying characteristics of alcohols for many microorganisms may also potentially be of use in crop protection. Greenhouse and field experiments were conducted to determine if foliar‐applied ethanol was effective against Septoria nodorum, the causal agent of leaf and glume blotch in spring wheat (Triticum aestivum). Ethanol (30 % and 60 %) decreased the disease symptoms on the leaves of wheat significantly when applied one day after the inoculation, although reductions in disease seventy were still observed until 4 days after the inoculation. In contrast, ethanol treatments before inoculation did not affect, or occasionally even enhanced, the disease development. On agar plate assay, the average sensitivity of S. nodorum on ethanol was high, as no reduction in its growth was observed at incubation times less than 10 or 20 min in 60% or 30% ethanol, respectively. Ethanol treatments did not damage the treated leaves, but a slight reduction in the leaf chlorophyll content as measured by SPAD values was observed. Ethanol application whether alone or with inoculation did not increase wheat kernel weights.
Effects of Stem‐injected Sucrose on Grain Production, Dry Matter Distribution, and Chlorophyll Fluorescence of Field‐grown Corn Plants
Authors: Zhou X. M. , Dutilleul P. , MacKenzie A. F. , Madramootoo C. A. , Smith D. L.
Published: April 2008

A field experiment was conducted to evaluate the effect of long‐term exogenous sucrose supply on aspects of corn plant physiology and development during the grain filling period. Concentrated sucrose solution was supplied to corn (Zea mays L.) stems by an injection technique. This injection technique delivered pressurized solutions through syringe needles sealed to the stem with latex. The pressure was applied to the syringe plunger with ceramic construction bricks. Solutions containing sucrose at 0, 150, and 300 g L−1 were injected over a 32 day period encompassing the duration of the active grain filling period. The primary ears of plants injected with sucrose produced approximately 50% more kernels and 30% more grain weight than those injected with distilled water. The injected internode was also considerably heavier (56%) for plants receiving 300 g sucrose L−1 than plants receiving distilled water. For all measured variables, plants injected with distilled water were either not different from or had larger values than the non‐injected controls. After one week sucrose injection caused photo‐synthetic inhibition (as measured by chlorophyll fluorescence) in the leaf just above the ear and the ear leaf, and this was more severe for plants receiving 300 g sucrose L−1 than for those receiving 150 g sucrose L−1. For sucrose injected plants, the increased size of the primary ear was concomitant with a large decrease in grain production by the secondary ear and an overall decrease in per plant grain production. These results suggest that the mechanisms for signalling between sinks (the primary and secondary ears) and the primary sink and the source (leaves) are different.
Development of Eco‐friendly and Non‐hazardous Weed Control Technology for Lowland Rice by Smothering through LDPE Film
Authors: Khan A. R. , Ghorai A. K. , Srivastava R. C. , Singh S. R.
Published: April 2008

Intensive use of chemical herbicides and pesticides has raised serious concern about their effect on non‐target organisms, plants, human bodies and the environment. Hence there is a continuous search for benign, harmless, non‐hazardous and eco‐friendly technology to control the growth of weeds which compete with crops for water, nutrients, light and space; thus reducing crop yield significantly. An attempt was made to control the weeds through smothering. This controls the weeds by cutting off light from the photosynthetic portion of weed plants by using black polyethylene sheets (LPDE film) which inhibit the top growth. Experiments to control the weeds in a lowland rice field through smothering were conducted in the high rainfall coastal region of eastern India wth eight treatments including smothering and conventional methods like hand/mechanical weeding and herbicides, etc. The treatment of smothering for one week + puddling + transplanting proved to be better than other conventional methods and may replace herbicide and hand/mechanical weeding totally with a better rice yield.
Breaking Uniculm Growth Habit of Spring Cereals at High Latitudes by Crop Management. I. Leaf Area Index and Biomass Accumulation
Authors: Peltonen‐Sainio P. , Peltonen J.
Published: April 2008

Spring cereals are commonly sown at high rates in Finland with the result that, under long day conditions, tillering is suppressed. If the apical dominance maintained by the shoot apex can be broken through altered crop management the possibility exists that the increased tillering allows a reduction in seeding rate. The objective of our study was to assess the effects of mechanical and chemical treatments, aimed at breaking the uniculm growth habit, on changes in green leaf area and consequently on biomass accumulation and partitioning in two spring oat, two spring barley, and two spring wheat cultivars. Results indicated that single applications of gibberellic acid (GA3), chlormequat chloride (CCC), and urea had no overall, persistent, advantageous effect on crop growth, even though occasional, temporary increases in LAI, and accumulation and partitioning of biomass, were recorded. Changes in crop structure, however, did not solely result from the increased contribution of tillers; treatments also accelerated main shoot growth. Following damage to the main shoot caused by mechanical treatments in particular, one of the tillers rapidly replaced the main shoot. Therefore, a low seeding rate associated with treatments aiming at breaking apical dominance cannot substitute for a high seeding rate at high latitudes. This was particularly the case in 1992 when early summer drought—prevalent in southern Finland ‐ resulted in peak values of LAI as low as ≤ 2 for wheat and ≤ 3 for oats and barley.
Chemical Composition of Pea Seeds as Related to Seed Yield under Arid and Semiarid Mediterranean Environments
Authors: Al‐Karaki G. N. , Ereifej K. I.
Published: April 2008

Little has been published on the chemical composition of pea (Pisum sativum L.) seeds and its relationship to seed yield. This study was conducted to investigate the relationships between seed protein, lipid, starch and sugars content of pea with seed yield under arid and semiarid Mediterranean environments. Twenty pea genotypes were grown at an arid (JUST) and semiarid (Maru) locations in northern Jordan. With the exception of glucose and fructose, the variation in protein, lipid, sucrose and starch was caused by environmental conditions. Pea grown at the semiarid location exhibited higher yield and the lower protein, glucose, fructose and sucrose contents than those grown at the arid location. Except for lipid and starch, high seed yields of genotypes were associated with low contents of protein and sugars, indicating that one‐sided selection for high seed yield tends to reduce the nutritional quality of pea seed.
Effects of Population Density on the Yield and Yield Components of Leafy Reduced‐stature Maize in Short‐season Areas
Authors: Begna S. H. , Hamilton R. I. , Dwyer L. M. , Stewart D. W. , Smith D. L.
Published: April 2008

Maize hybrids which yield well, mature earlier and tolerate higher population densities better than the currently available hybrids would be more suitable for production in short‐season areas. Leafy reduced‐stature maize hybrids, which have only recently become available, have traits which address these criteria. The objective of this study was to evaluate the effects of different population densities (50000, 100000, 150000, and 200000 plants ha−1) on the yield and yield components of one leafy reduced‐stature (LRS), one non‐leafy reduced‐stature (NLRS), and two conventional control hybrids (Pioneer 3979, <2500 CHU; and Pioneer 3902, 2600–2700 CHU) at two locations. All hybrids had the highest kernel number per row and single plant grain yields at the lowest population densities, however, as plant density increased these variables decreased more in the conventional hybrids than the LRS and NLRS hybrids, which demonstrates the greater tolerance of the latter to the stresses associated with higher plant densities. Grain yield was highest for all hybrids, except for NLRS, at 100 000 plants ha−1 with the LRS hybrid and Pioneer 3902 having the highest yields (11.4 vs. 9.8; 12.0 vs. 10.4) at locations 1 and 2 respectively. The LRS hybrid matured before either of the conventional hybrids and out yielded Pioneer 3979 at both sites. Harvest index was not affected by population density and this value was not different among the NLRS and conventional hybrids. However, the harvest index of the LRS hybrid was greater than the others. LRS and NLRS hybrids had lower moisture contents and earlier maturities than conventional hybrids. Rapid growth of the first ear, a higher yield per unit leaf area, and a higher harvest index are indications that LRS hybrids should be more tolerant of higher population densities than the conventional hybrids.
Effects of 2,4‐D and Azospirillum brasilense on Nitrogen Fixation, photosynthesis and Grain Yield in Wheat
Authors: Elanchezhian R. , Panwar J. D. S.
Published: April 2008

The effects of 2,4‐D with or without Azospirillum hra‐iiknse (Sp7) on nodulation of wheat (cv HD2428) have been investigated under hydropooical conditions. In the nutrient medium, varying concentrations of N and 2,4‐D were used for growing wheat seedlings, N free Hoaglatid solution along with 2,4‐D (0.5 ppm) was found to be the best concentration for noduiation and growth of the seedings, The nilrogenase activity (acetylene reduction y was relatively higher in plants treated with 2,4‐D artd Azospirillum ihan with Azospirillum alone. This seemed to be due to the formation of nodule like stiucture serving as mche for azospirilla to protect it from oxygen. These results confirmed tlie nitrogenase activity of Azospirillun brasiknse in association with the 2,4‐D induced nodules of wheat. Plants inoculated with Azospirillum either alone or with 2,4‐D were transplanted info pols. The photosynthctic rate, chlorophyll content. NRA, grain yield and N content were found to be higher in inoculated plants. The translocation of current photo‐synthates (14C sucrose studies) towards roots was higher in these treatments. Thtss the growth of Azospirilfum and nodule formatioo depend on availability of current photosynthatcs of hosl plants.
Effects of Waterlogging Followed by a Salinity Peak on Rapeseed (Brassica napus L.)
Authors: Boem F. H. Gutierrez , Lavado R. S. , Porcelli C. A.
Published: April 2008

Due mainly to alterations in plant metabolism, lack of oxygen and excess salts are disturbances that affect crop yields. In different parts of the world crops are subjected t o those disttirbances, simultaneously or successively. Our objective was to determine the effects of a winter waterlogging followed by a spring salt peak on rapeseed yield, A pot experiment, combining waterlogging and salinization was carried out. The waterlogging duration was: 0 (control), 3, 7 and 14 days and the sahnity treatments were peaks of Electrical Conductivity of 5 and 8 dSm−1 and the control. The yield started decreasingfrotn 3 days during waterlogging, mainly due to the lower number of seeds per plant. The salt peak from 5 dSm−1 affected the yield only in plants which had suffered a waterlogging lower than 7 days, showing interaction between salinity and waterlogging, Only salinity reduced oil content. The saline peak affected the K, Ca and Na concentration in plant tissues, but the effect of salinity on rapeseed could be more related to soil water potential than specific ion toxicities or imbalance.
Effects of Two Planting Systems on Soil Structure and Root Growth of Maize (Zea mays L.)
Authors: Sidiras N. , Kendristakis E.
Published: April 2008

In 1994 two planting systems of maize—rotary hoe‐sowing (RS) and plough (2 diskings) sowing (PDS)—were compared in the field with respect to their influence on the root growth of maize and on selected physical properties. Roots were sampled at the five‐leaf stage (S:5) and the milk stage of the maize seeds (S:MS).

Generally, in the PDS planting system the roots were richer compared to the RS. At the S:5 stage the correlation coefficient between the physical properties and the toot system was considerably higher, while at the S:MS stage the corresponding correlation coefficient was much lower.

In the RS planting system, at 15 cm and 30 cm distances from the sowing rows, far fewer roots were observed than in the PDS one.
Leaf Area Duration of Oat at High Latitudes
Authors: Peltonen‐Sainio P.
Published: April 2008

Contribution of leaf area duration (LAD) to grain yield during the short growing season characteristic of northern latitudes may differ from the marked impact it has at lower latitudes. Three experiments (exps) were carried out at Viikki Experimental Farm, University of Helsinki, Finland (60° 13′N) to compare associations between main shoot and tiller LAD with grain yield, yield components and morpho‐physiological traits characterizing plant stand structure. This was done using correlation analysis and principal component analysis (PCA) for data from trials conducted during 1993–1995. Exp I included three N fertilizer rates (80, 120, 160 kg N ha−1), three seeding rates (250, 500, and 750 seeds m−2), and tall, moderate, semi‐dwarf, and dwarf oat lines. Exp II incorporated two N fertilizer rates (80 and 120 kg ha−1), three seeding rates (400, 600, and 800 seeds m−2), and naked and hulled oat lines, and exp III, foliar applications of plant growth regulators [control, chlormequat chloride (CCC), and ethephon], and dwarf, naked, and conventional oat lines. LAD for main shoots and tillers [calculated as ∫ LAI d T, where T is cumulated degree days from seedling emergence to yellow ripening (dd °C)] and 12 morpho‐physiological traits were measured. Oat was not able to benefit from high main shoot LAD if drought occurred at grain‐fill, but in the absence of severe drought or if it occurred at pre‐anthesis, high LAD favoured yield formation. Tiller LAD had a negative impact, if any, on grain yield in cases of an inverse relationship between tiller LAD and yield components on main shoots was recorded. Use of low seeding rates resulted in improved ability of total LAD to contribute to dry‐matter production, but was not associated with grain yield. Low seeding rates enhanced formation of high tiller LAD, which was not able to compensate for grain yield reduction caused by fewer main shoots. Foliar application of CCC and ethephon tended to increase the proportion of LAD production by tillers at the expense of grain yield, which can be attributed to lower post‐anthesis precipitation. Oat types differed in main shoot and tiller LAD. Disadvantageous characteristics of naked oat, such as low single groat weight, were not associated with insufficient main shoot LAD. High tiller LAD in naked lines and the Minnesota‐adapted dwarf line that was not associated with high tiller grain yield in naked lines, in particular, indicates that tiller growth was enhanced at the expense of grain yield production. Application of N fertilizer at various rates did not have any effect on LAD.
Effect of Progressive Drought on Endoproteolytic Activities and Water Status of Brassica napus Leaves
Authors: Ilami G. , Contour‐Ansel D.
Published: April 2008

Rapeseed (Brassica napus L. var. oleifera) is known to display adaptive responses under drought stress, especially in leaves. The aim was to study the influence of water deficit on endoproteolytic activities and water status of leaves developed before (L3 leaf) or after the onset of water stress (L2 and L3 leaves). Although the impact of senescence on proteolytic activities is well known, little information is available on the effect of water deficit on such activities. Seedlings of rapeseed were submitted to controlled progressive drought. Soil water potential (T) and soil dry weight humidity (H) were measured daily in the dark. Endoproteolytic activities were assayed both on control and water‐stressed plants using azocasein as substrate after partial purification of the extracts, Two zones of maximal activity were detected, the first between pH 4.5 and 6.0 and the second at pH 8.0 as a sharp peak, in control as well as in drought stressed‐plants. While LI leaf was very sensitive to water stress and wilted when ψ reached −2.8 to −3.2 MPa, L2 leaf began to display signs of senescence for this value whereas L3 leaf which showed the lowest endoproteolytic activities, remained turgid, hardened and developed a typical bluish coloration. The relation between the acquired resistance of young leaves, the low endo‐proteolytic activity and the induction of a 22 kDa protein under progressive drought is discussed.
A Pot Technique to Screen Pigeonpea Cultivars for Resistance to Waterlogging
Authors: Chauhan Y. S. , Silim S. N. , Rao J. V. D. K. Kumar , Johansen C.
Published: April 2008

To develop a preliminary screening procedure for waterlogging resistance, a waterlogging resistant ICP 8379 and a waterlogging susceptible cultivar ICP 7035 were grown i n pots using different growth media and subjected to 6 days of waterlogging. Waterlogging caused a significant reduction in root dry mass of both cultivars which was greater in ICP 7035 than tn ICP 8379, The reduction i n shoot dry mass was comparatively small. The most conspicuous differences between the two cultivars occurred in terms of plant survival. In different soil treatments, ICP S379 showed 0–38 % mortality and ICP 7035 showed 63–100% mortality. The variation in mortality occurred in response to differences in growth medium. Using the growth medium that gave maximum differences, eight additional cultivars were compared along with ICP 7035 and JCP 8379. Significant differences m plant mortality among different cultivars were observed, A number of cultivars showed similar low mortality as ICP 8379, Therefore, there appears to be a potential t o use this method for preliminary screening of a large number of pigeonpea cultivars for waterlogging resistance.
Effect of Irrigation and N‐Fertilization (Fertigation) Scheduling on Tomato in the Jordan Valley
Authors: Deek J. M. , Battikhi A. M. , Khattari S.
Published: April 2008

Tomato (Lycopersicon esculentum mill. cv. Petopride) is the most important vegetable crop in Jordan; its production is characterized by inadequate irrigation and fertilization practices, especially under open field conditions. A field study was carried out to determine the effect of different irrigation intervals and different N‐fertilizer doses on water use, tomato yields and residual soil nitrogen.

Results indicated significant differences in water use and tomato yields between irrigation treatments. Highest yield (51.4 ton ha−1) was obtained under three irrigations per week with 504 mm total water supply, whereas under irrigation once a week 35.3 ton ha−1were produced with 353 mm total water supply. There were no significant differences in yield between fertigation with ten equal time intervals and fertigations with intervals as per crop requirements, the yields were 47.1 ton ha−1 and 44.5 ton ha−1, respectively. However, yield was significantly lower with three fertigations at equal intervals and equal doses (35.8 ton ha−1) throughout the season. There were no significant differences between mineral nitrogen forms in terms of yield effects. Significant irrigation effects were observed on total soil nitrogen. Residual soil N was 0.052% in the surface layer (0–30 cm), and 0.030% in the subsurface layer (30–60 cm).
Agronomical Performance Among Farro Species and Durum Wheat in a Drought‐Flat Land Environment of Southern Italy
Authors: Troccoli A. , Codianni P. , Ronga G. , Gallo A. , di Fonzo N.
Published: April 2008

The aim of this study was to evaluate the agronomical performance of old unhuUed wheat species (farro) in comparison with an old cultivar of durum wheat, selected for morphological and rusticity characteristics similar to farro, in a drought‐flat land environment of southern Italy. The trials were carried out during the 1992/93 and 1993/94 growing seasons. Agronomical responses concerned the behaviour of the different species to weeding treatment (diclofop‐methyl, 568 g a.i, ha−1) and to three (0%, 50%, 100%) artificial weed levels with Avenafatua and Phalaris arundinacea with respect to grain yield and its components, plant morphological aspects and two qualitative characters. In all of the species the weeding treatment increased the mean values of almost all the parameters analysed except for days to head and grain protein content which remained constant. The effect of weed treatment on the characters considered was a general decrease of mean values when weed level was increased. The grain protein content showed an opposite trend. As far as the grain yield alone is concerned, yielding differential in medium and large farro decreased by 3% whereas in small farro it increased by 4.3% vs, durum wheat when no weeding and weeding treatments were compared. Small and large farro resulted more susceptible than medium farro and durum wheat to weed treatment. In fact, these latter showed, at the maximum weed level, the same grain yield loss as small and large farro at the 50% weed level. Small farro was the most susceptible species, while Triticum dicoccum showed similar affinity and behaviour to durum wheat.
Effect of Irrigation on Winter‐Sown Chickpea in a Mediterranean Environment*
Authors: Malhotra R. S. , Singh K. B. , Saxena M. C.
Published: April 2008

In the dry Mediterranean environments of the West Asia and North Africa region, irrigation is frequently used to supplement rainfall to increase crop productivity and yield stability. Chickpea (Cicer arietinum L.), an important pulse crop of the region, often suffers from drought and can benefit from such a practice. To investigate the response of chickpea to irrigation, experiments were conducted in the field at Tel Hadya, Syria, from 1985 to 1988 using 24 improved chickpea genotypes sown in winter. Irrigation scheduling was done using the daily water balance computed from rainfall and pan evaporation data. Yearly rainfall was 316, 358, and 504 mm and supplemental irrigation amount was 130, 120, and 80 mm in 1985–86, 1986–87, and 1987–88, respectively. Irrigation increased seed yield by 916 kg ha−1 (44.0%) over the 3‐year period. Irrigation requirement for chickpea coincided with flowering and seed development period. The top 10 highest‐yielding genotypes under irrigated conditions were ILC 464, ILC 1272, ILC 237, ILC 613, ILC 95, ILC 4291, ILC 142, ILC 147, ILC 295, and ILC 3256. Their mean seed yields ranged from 3877 to 3208 kg ha−1. Among these four genotypes, ILC 464, ILC 1272, ILC 3256, and ILC 4291 with mean seed yields of 3877, 3726, 3208, and 3266 kg ha−1, respectively, were with predictable response to favourable conditions. Aboveground biomass contributed 49% of the total increase in seed yield from irrigation followed by plant height (26%) and early maturity (16%). These results indicate that it may be possible to breed chickpea for improved response to irrigation, and irrigation can enhance the yields of winter‐sown chickpea grown in the lowland Mediterranean drylands.
Dry Peas (Pisum sativum L.) Grown in Mixtures with Faba Beans (Vicia faba L.)—A Rewarding Cultivation Alternative
Authors: Stelling D.
Published: April 2008

Two semi‐leafless pea cultivars and two highly lodging‐resistant faba bean cultivars were grown in a series of replacement trials conducted on a highly fertile loam soil near Gottingen from 1992 to 1995. Cultivation as well as harvesting of mixed crops of both species proved possible. In spite of the delayed harvest of the mixed crop stands determined by the later pod ripening of the faba beans (varying between seasons from ‐f 5 to +21 days), noticeable seed losses due to pod shattering were not observed for the overripe peas. Standing ability of the peas was considerably improved by mixed cropping. Lodging began later and was less severe at harvest. Within mixtures with 50 % or more faba bean proportions at sowing (relative to the seeding rate of the pure stands) the peas, n i most cases, remained nearly upright until harvest and instead of the usual ‘Plattlager’, i.e., prostrate but upright top, frequently a more highly inserted ‘Hohllager’, i.e., upright but collapsed at higher nodes, was observed. In contrast to these remarkably synergistic effects for standing ability, such effects proved to be only small and nonsignificant for grain yield (−1.5–2.9%). Yield stability of the mixed crops was higher than that of the pure stands of both species. Estimates of the stability parameters, ecovalence, deviation from regression and environmental variance were at least halved. Yield proportions of peas and faba beans in the harvested seed of the mixtures did not correspond with the seed proportions at sowing. They differed considerably between seasons and cultivar combination. Higher yield proportions of faba beans were observed under wet and cold weather conditions and for the cultivar combination Victor/Disco, whereas higher yield proportions of peas were found under dry and warm weather conditions and for the cultivar combination Mythos/Baroness.
Field Observations on Interactions betweenOrobanche cernuaLoefl. and Bidi Tobacco in Nipani, India
Authors: Dhanapal G. N. , Struik P. C. , Ter Borg S. J.
Published: April 2008

Interactions betweenOrobanche cernuaand bidi tobacco were recorded in naturally infested tobacco fields at Nipani, India. At harvest, most broomrapes occurred in clusters of 4–9 spikes per tobacco plant. The effects of broomrapes became visible at 50 days after transplanting tobacco and were mainly caused by a reduction of the growth rate of the tobacco plant and not by shortening the growth period. The tobacco crop grew exponentially until 60 days and thereafter linearly in the period 60–140 days after transplanting. From 140 days onwards the growth of the crop became truncated. The reduction in tobacco yields depended on the number of broomrapes per tobacco plant. Individual broomrape spikes were lower in dry weight when more spikes occurred per tobacco plant.
Investigations on Heat Tolerance of Spring Wheat Varieties of Different Origin Under Growth Chamber Conditions
Authors: Leithold B. , Müller G. , Weber W. E. , Westermann T.
Published: April 2008

Winter wheat has replaced spring wheat to a large extent under the climatic conditions of Western and Central Europe. But spring wheat genotypes are still important under the warm climate in large parts of Africa and Central America, since spring wheat needs no vernalization. To reach optimal yield, genotypes must be well adapted to heat stress. In this study 11 spring wheat varieties of Egypt, Sudan, CIMMYT and Germany were exposed to high temperatures at ear emergence and beginning of anthesis. There were reductions in kernel yield and kernel number of the main ear for all genotypes, but the differences in reduction were remarkable. The German variety ‘Naxos’ was best adapted. Some varieties showed an increased number of florets per spikelet under heat treatment, but this does not prohibit a reduction in kernel number per spikelet.
Allelopathic Effect of Eucalyptus globulus Labill. on Cyperus rotundus L. and Cynodon dactylon L. Pers.
Authors: Babu R. Chandra , Kandasamy O. S.
Published: April 2008

The allelopathic potential of Eucalyptus globulus Labill. (gum tree) fresh and dried leaf leachates was studied using two perennial weeds, viz. purple nutsedge (Cyperus rotundus L.) and bermuda grass (Cynodon dactylon L. Pers) as test weeds. Aqueous leachate of fresh leaves of eucalyptus significantly suppressed the establishment of vegetative propagules and early seedling growth of the weeds. Leachate of fresh leaf cuttings had growth inhibitory effect on bermuda grass but showed growth promotion effect on purple nutsedge. Similarly the leachate of dried leaves of eucalyptus had differential influence on the growth of the two weeds. There is a possibility to harness the allelochemicals of eucalyptus leaves as herbicides for the management of these perennial weeds.
Quantitative Change of Carbohydrate Content of Two Varieties of Jerusalem Artichoke Tubers (Helianthus tuberosus L.) During Cold Storage Conditions (4°C)
Authors: Ben Chekroun M. , Amzile J. , Mokhtari A. , El Haloui N. E. , Prevost J.
Published: April 2008

The Jerusalem artichoke (Helianthus tuberosus L.) represents an interesting source of carbohydrate because of its high fructose content (75% of total carbohydrates). An experiment on storage of two varieties of the Jerusalem artichoke tubers (‘Kharkov’ and ‘Violet de Rennes’) showed that the quality of tubers was preserved during the first 7 weeks of cold storage. Beyond this period, the loss in total carbohydrate content was evaluated at 0.19% for the ‘Kharkov’ and 0.26% for the ‘Violet de Rennes’ variety of the fresh matter/week. Between the seventh and the thirteenth week of cold storage the tubers lost about 16.7% and 19.1%, respectively, of their initial carbohydrates. From this study we came to the conclusion that storage at 4°C for the two varieties (‘Kharkov’ and ‘Violet de Rennes’) beyond 7 weeks would cause a decrease of general reserves in tubers.
Nitrogen Mineralization Pattern of Agroforestry Tree Leaves under Tropical Highland Conditions
Authors: Anthofer J. , Hanson J. , Jutzi S. C.
Published: April 2008

Leaves of nine agroforestry tree species (Grevillea robusta, Erythrina abyssinica, Gliricidia sepium, Albizia schimperiana. Acacia nilotica. Acacia polyacantha, Leu‐caena leucocephala, Leucaena pallida and Entada abys‐sinica) were compared in a glasshouse incubation experiment under natural temperature conditions to relate the observed nitrogen mineralization pattern to quality factors of the mulch material such as N, lignin, phenolic and tannin content and C/N ratio, lignin/N ratio, phenolic/N ratio and (lignin ‐I‐ phenolics)/N ratio. Separation of the plant material into leaflets and petioles/rachis or into leaves and petioles with subsequent chemical analyses revealed large differences in the quality of the material not only between species but also amongst plant parts within the same species. Erythrina abyssinica, G. sepium, L. leucocephala and L. pallida had a rapid nitrogen release especially during the early sampling dates and were superior compared with mulch treatments of G. robusta, A. polyacantha, and Entada abyssinica. Immobilization processes started around 5 weeks after incubation and continued up to the end of the experiment, 9 weeks after incubation. N and lignin content, C/N ratio, lignin/N ratio, phenolics/N ratio and (phenolics + lignin)/N ratio were all significantly correlated with mineralized nitrogen after 3 weeks but their influence in driving the mineralization pattern decreased with incubation time.
Effect of Sodium Chloride on Growth, Photosynthesis and Mineral Ions Accumulation of Different Types of Rice (Oryza sativa L.)
Authors: Khan M. S. A. , Hamid A. , Salahuddin A. B. M. , Quasem A. , Karim M. A.
Published: April 2008

Growth, photosynthesis and mineral ions accumulation of aromatic small grain, local coarse grain and HYV types of rice were evaluated under saline conditions. Three cultivars from each type were subjected to 0, 50, 100, 150 and 200 mvi NaCl concentrations. After three weeks of 200 mvi NaCl application only Pokkali and Kalobail, both belonging to the local coarse grain type and IPK 37011 of the HYV type were able to survive. Plant height, green leaf area, leaf weight, shoot and root growth were seriously decreased by salinity. However, leaf area was decreased more than other growth parameters. In general aromatic small grain type showed higher salt‐sensitiveness in relation to growth than other types of rice. Photosynthesis (Pn) was decreased by salinity and apparently stomatal resistance was partially responsible for the decreased Pn. Kalijira, an aromatic small grain eultivar, showed serious reduction in Pn, especially at the 150mM NaCl level. Na accumulation was increased while K accumulation was decreased by salinity in all types. Salt tolerant eultivars in all types of rice accumulated less Na and more K than susceptible ones. The K/Na ratio was also higher in tolerant eulti‐vars. Ca and Mg eoncentrations were decreased by salinity although not all the eultivars showed clear accumulation patterns as observed for Na and K. As HYV and local coarse grain types of rice in general showed high salt tolerance, a comprehensive breeding programme should be of value for the improvement of salt tolerance of aromatic small grain rice which has a high demand in rice importing countries.
Phenological Growth Stages of the Soybean Plant (Glycine max L. MERR.): Codification and Description According to the BBCH Scale*
Authors: Munger P. , Bleiholder H. , Hack H. , Hess M. , Stauss R. , van den Boom T. , Weber E.
Published: April 2008

Following the introduction of the general BBCH scale, the specific BBCH scale for the soybean plant is presented, with crop‐specific descriptions and detailed assessment instructions.

The phenological development process of the plant is described in terms of periods (principal growth stages) and steps (secondary growth stages). A two‐digit and a three‐digit decimal code suitable for data processing in crop production experiments is assigned to each developmental step.
Smut Disease and Yield Performance in Corn (Zea mays L.) as Influenced by Nitrapyrin, Urea and Zinc Applications in Coarse‐textured Soils
Authors: Kostandi S. F. , Soliman M. F. , Ghaly A. A.
Published: April 2008

The effects of nitrapyrin (NI), urea (U) and Zn rates on rhizosphere pH, smut incidence (S.I.), dry matter (D.M.), grain yield (G.Y.) and ear leaf N and Zn contents were studied in cemented plots, containing calcareous and non‐calcareous soils. Treatments were comprised of 3 U applications (46, 92 and 138 kg N acre−1), combined with 2 NI rates (0 and 0.22 kg acre‐1) and 2 levels of Zn (0 and 8 kg acre‐1). Corn seeds, cv ‘Amoun’ were planted in 1993 and 1994 and the seedlings were artificially infected with U. maydis‐spores at the 6 and 10 leaf growth stages. Results have shown that corn plants grown in calcareous soil imposed greater advantage in D.M. and G.Y., accompanied by a relatively low smut infection than those grown in non‐calcareous soil. Unlike the diversion effects of NI on soil pH and plant Zn content, its application was beneficial for improving yield and plant Zn content. Urea applications decreased the soil pH by 0.6 unit at the highest N rate and exerted stimulatory effects on ear leaf N and Zn contents. By increasing U rate to 138 kg N acre‐1, smut severity was increased by 6%. In contrast, by Zn fertilization, smut severity was decreased by 10.3%, accompanied by marked increases in G.Y. and leaf Zn content. Mixed results were detected on S.I. data, when NI was combined with U rates. In the presence of Zn, smut severity was dropped to 20.1% at 138 kg N acre‐1. The results also showed that in the absence of Zn supply, S.I. was dominated in NI‐treated plants and the reverse was true when Zn was included. Satisfactory results were achieved when 92 kg N acre‐1 were combined with 0.22 and 8 kg acre‐1 of NI and Zn, respectively.
Effect of Sowing Date and Cutting Stage on Yield and Quality of Irrigated Barley and Triticale Used for Forage and Grain
Authors: Royo C. , López A. , Serra J. , Tribó F.
Published: April 2008

The influence of cutting stage on forage and grain yield and quality has been studied in three barley and one triticale varieties, using two sowing dates in each of two sites. When cut at the first detectable node stage (C.31), forage yield was almost double the yield at the pseudo‐stem erect stage (C.30). Barley yielded more forage than triticale at both cutting stages. Both species had similar forage protein content, but forage fibre content was greater in barley than in triticale. Cutting at stage 30 reduced grain yield by about 11 % and at stage 31 by nearly 35 %. Barley and triticale had similar grain yield. Grain protein content was not affected by forage removal, but was significantly greater in triticale than in barley. The later the stage of cutting, the greater was the delay in heading date. Triticale was more responsive to environmental conditions than barley.
Effect of the Herbicide Paraquat on the Decomposition of Wheat Straw
Authors: Hunter W. J.
Published: April 2008

The effect 1,1′‐dimethyl‐4,4′‐bipridinium dichloride (paraquat) has on wheat residue decomposition was investigated in laboratory studies. Field dried straw containing 0.30% nitrogen and 42.9% C was incubated in laboratory bioreactors for 8 weeks. Treatment combinations per gram of straw were control (no paraquat or spreader), 0.26, 2.6, and 26 ng paraquat, 0.7 nl Valent X‐77,0.26 ng paraquat plus spreader and 2.6 ng paraquat plus spreader. Decomposition was monitored by CO, production and dry weight changes. Neither paraquat nor its spreader, alone or in combination, were found to effect CO2 production or dry weight Ioss. Paraquat should not increase the rate of wheat straw decomposition at field application rates.