bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tall and Hard Fescue Responses to Periodic Soil Water Deficits
Authors: Brar G. S. , Palazzo A. J. 
Published: April 2008

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

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

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

AbstractIn order to understand the nature and causes of chlorosis at Metahara Sugar Estate (8°53′N and 39°52′E) in Ethiopia, soil profile samples were collected from a ratoon field that exhibited chlorosis. From the same site, the first ratoon sugar cane leaf blades (+ 3) were sampled on the basis of the degree of chlorosis, and thus categorised into green, medium green, medium yellow and yellow. Soil sample analysis indicated that DTPA‐extractable Fe, Mn and Cu were adequate for normal plant growth in spite of an increase in CaCO3 content. Moreover, the chlorotic leaves contained higher iron content than the green ones. Consequently, it is concluded that iron chlorosis of sugar cane at Metahara could be due to physiological inactivation of iron in soils and the plant.A field experiment was also conducted using sugar cane variety CO‐449 in order to select the most effective iron source to control iron chlorosis of the plant. The plots received the treatments of FeSO4, EDDHA and DTPA at three different levels each as foliar sprays. The untreated plots were used as control. The chemicals were applied on the first ratoon 3 weeks after harvest, and repeated a week after the first spray. Twenty millable canes from the middle two rows were sampled at 12 months for yield and juice quality determinations. Iron sulphate spray at 15 kg ha‐1 increased cane length and commercial cane sugar by 33 and 44 % over the control, respectively. The highest cane yield was secured by spraying DTPA at 1.80 kg ha‐1 even though its recoverable sugar percentage was low. Not all sources of iron improved juice quality.Since FeSO4 at 15 kg ha‐1 was equally effective as the 30 kg ha‐1 FeSO4, applications, the need to consider other than the currently used rate in the Estate is timely and is very important.
Zum Einfluβ interspezifischer Konkurrenz in einer Kleegrasmischung auf die Futterqualität
Authors: von Boberfeld W. Opitz , Biskupek B. 
Published: April 2008

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

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

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

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

AbstractChemical fixation and critical point drying of plant tissue prior to scanning electron microscopy often degrades the outermost layer of the specimen, i.e. the epicuticular wax. Knowledge of the unaltered wax, including its morphology, is important because the wax constitutes the interface between the plant and its surroundings. Having worked previously with barley leaves (anatomy, infection biology of pathogens), we found it of interest to examine and describe the wax morphology on barley leaves and to determine whether or not there were differences between cultivars. Hence, the morphology of the epicuticular wax on the first leaf of two spring barley cultivars has been studied by scanning electron microscopy following cryofixation.The wax on both cultivars consists chiefly of scales with a small proportion of rods and granules. There is little variation in wax morphology over each leaf side, and only minor differences between the abaxial and adaxial sides of the same leaf. Distinct differences are, however, observed between the two cultivars, especially regarding the thickness and the shape of the wax scales. The wax bodies cover the entire surface of a leaf except for parts of trichomes and guard cells, and some scattered wax free areas.The morphology and distribution of wax are discussed in relation to studies made on barley leaves using different techniques. Also, the implications of wax morphology for disease resistance are briefly discussed.
Macro‐nutrient Status of Brassica napus and Brassica juncea Grown Under Swedish Conditions
Authors: Kjellström C. , Kirchmann H. 
Published: April 2008

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

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

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

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

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

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

AbstractDuring 1990 and 1991 growth seasons at two locations in Peru four sweet potato cultivars were tested for their response to a short‐term shading. The plants were subjected to artificial shade (42 % light reduction) for 1 month at different growth stages.A high genetic variability was found in the extent to which tuber and total biomass yield of sweet potato was affected by sub‐optimal light conditions. One cultivar was completely tolerant to shade at all growth stages, whereas the others showed a yield decline between 20 % and 55 %. Generally tuber yield was most reduced when shade was imposed at the end of the growth season (fourth and fifth months) and the least at its beginning (first and second months). Yield losses were due to a diminished biomass production and/or an altered assimilate partitioning within the plant. Tuber formation was affected rather than tuber initiation.
A Proposed Index for Assessment of Row‐replacement Intercropping System
Authors: Banik P. , Bagchi D. K. 
Published: April 2008

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