bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development in Cowpea (Vigna unguiculata). III. Effects of Temperature and Photoperiod on Time to Flowering in Photoperiod-sensitive Genotypes and Screening for Photothermal Responses
Authors: Craufurd P. Q. , Qi A. , Summerfield R. J. , Ellis R. H. , Roberts E. H. 
Published: October 2008

SUMMARYSeventeen photoperiod-sensitive genotypes of cowpea (Vigna unguiculata) were grown in approximately 30 photothermal environments in Nigeria. Photoperiods ranged from 10 to 16 h d−1, mean temperatures from 19° to 30°C and times from sowing to flowering (f) from 32 to 140 d. Rate of progress towards flowering (1/f) was related to mean pre-flowering values of temperature and photoperiod using simple linear rate models comprising one, two or three planes (thermal, photothermal and insensitive). There were no significant differences (p > 0.25) among genotypes in response to temperature within the thermal plane and the common base temperature was estimated to be 7.6°C. Photoperiod-sensitivity varied by a factor of 15 among genotypes, and the critical and ceiling photoperiods varied from 12.2 to 13.4 and from 13.8 to more than 16 h d−1 at a mean temperature of 27°C, respectively. These simple models satisfactorily predicted f in an independent data set (R2 = 0.62) for plants grown in the main cowpea growing seasons at latitudes between 7° and 13°N. The utility of photothermal models and methods to screen for photothermal responses are discussed.
Effect of Leaf Stripping, De-tasselling and Topping of Maize on the Yield of Maize and Relay Intercropped Finger Millet
Authors: Subedi K. D. 
Published: October 2008

SUMMARYA field experiment was conducted to study the effect of leaf stripping, de-tasselling and topping on the yield of maize and finger millet in a maize/finger millet intercropping system at Lumle in Nepal. De-tasselling of maize before pollen shedding reduced the number of barren plants, and increased test weight and grain yield but de-tasselling after pollination had no significant effect. Defoliation of maize by removal of leaves below and above the ear, or by topping 30 days after 50% silking, had no effect on either maize grain yield or on that of the relay planted finger millet. This contradicts the hypothesis that increased light penetration due to reduced shading improves the yield of millet under maize.
The Influence of Time of Planting and Spacing on the Production of Fodder and Fuelwood in Associations of Calliandra calothyrsus and Pennisetum purpureum Grown on Contour Bunds in the Highlands of Burundi
Authors: Akyeampong Ekow 
Published: October 2008

SUMMARYThe best time to plant Calliandra calothyrsus in association with Pennisetum purpureum and the appropriate in-row spacing of Calliandra for fodder and fuelwood production when grown on contour bunds were investigated. Main plot treatments were Pennisetum planted in November 1988 and associated with Calliandra in February 1989, Calliandra planted in November 1988 and associated with Pennisetum in February 1989, and both species planted simultaneously in November 1988. Sub-plot treatments were three within-row spacings of Calliandra. Survival of neither species was affected by time of planting. Total treatment yields of the second and third years were not influenced by time of planting but lower yields of leaf and wood were obtained from the later-planted Calliandra. Total yields were not significantly influenced by the spacing, but leaf and wood yields of the Calliandra at the 25 cm spacing were greater than those at the 100 cm spacing although not significantly different from those at the 50 cm spacing. Neither the time of planting nor the spacing of Calliandra affected the yield of maize or beans grown in the interbund areas. Simultaneous planting of Calliandra and Pennisetum is recommended.
Rainfall Erosivity and Erodibility of Inceptisols in the Southwest Colombian Andes
Authors: Ruppenthal M. , Leihner D. E. , Hilger T. H. , Castillo F. J. A. 
Published: October 2008

SUMMARYThe rainfall erosivity (R) and soil erodibility (K) factors of the Universal Soil Loss Equation (USLE) were determined on two sites in the Colombian Cauca Department over a five year period when rainfall was mostly lower than average. The results showed that the high erosion potential of the soils can be attributed more to high rain erosivity than soil erodibility. The R factor explained between 59 and 81% of the variation in soil loss recorded on continuously clean-tilled fallow plots. The erodibility of Inceptisols in the study region is classified as low. Values for soil erodibility (K) ranged from 0.012 to 0.015 (measured in SI units) in the fifth year of permanent bare fallowing. K factors were higher in the rainy than in the dry season. Soils, previously under grass vegetation, were very resistant to erosion in the first two years of bare fallowing. In the third year erodibility increased sharply and continued to increase steadily until the sixth year. K factors predicted by the USLE nomograph underestimated the empirically-determined erodibility of these highly aggregated clay soils.
Physiological and Morphological Features Determining the Performance of the Sorghum Landraces of Northern Nigeria
Authors: Flower D. J. 
Published: October 2008

SUMMARYSorghum landraces from contrasting districts of northern Nigeria were grown during the 1990 rainy season to describe their physiological and morphological features. Changes in their dry matter production and yield could be predicted from thermal time to flowering (based on response to a fixed daylength) and partitioning indices. Many other morphological and physiological features, such as light-extinction coefficient, light-use efficiency, plant height, leaf area and leaf number, were either stable or varied systematically with time to flowering. Grain yields of early maturing lines were limited by low light interception from flowering to physiological maturity and those of later maturing lines by highly site-specific drought stress.
Problems Associated with Phalaris minor and Other Grass Weeds in India and Pakistan
Authors: Shad Rashid A. , Siddiqui Sadar Uddin 
Published: October 2008

SUMMARYThe composition and control of the grass weed flora of India and Pakistan are discussed, and the losses caused by the weeds are reviewed. The most important perennial weeds are Cynodon dactylon and Sorghum halepense and the most important annual weeds Echinochloa crusgalli and E. colona in the summer (kharif) crops and wild oats (Avena spp.) and Phalaris minor in the winter (rabi) crops. Losses caused by these weeds can be considerably reduced by the use of selective herbicides but these may be too expensive for many farmers. The problems and control of Phalaris minor are considered in detail.
Adoption of Improved Cultivars of Pearl Millet in an Arid Environment: Straw Yield and Quality Considerations in Western Rajasthan
Authors: Kelley T. G. , Parthasarathy Rao P. , Weltzien R. E. , Purohit M. L. 
Published: October 2008

SUMMARYThe role of straw yield and quality in farmers' decisions about the adoption of pearl millet cultivars in western Rajasthan was examined using farm household surveys. Information on the relative importance of grain versus straw yield, the perceived risks associated with the use of new cultivars under variable climatic conditions and perceptions of straw quality indicated that improved cultivars of pearl millet were not adopted primarily because of poor grain yield in years with low rainfall, though poor straw yield in such years was also important. These results are particularly pertinent in the light of farmers' perceptions of the likelihood of experiencing drought or low rainfall. If new cultivars of pearl millet are to replace the traditional ones, they must perform better under conditions of limited rainfall.
Soil Fertility Decline and Fallow Effects in Ferralsols and Acrisols of Sisal Plantations in Tanzania
Authors: Hartemink Alfred E. , Osborne J. F. , Kips Ph. A. 
Published: October 2008

SUMMARYSoil fertility decline and fallow effects were studied in Ferralsol-Acrisol catenas of plantations of sisal (Agave sisalana) in north-east Tanzania. The fertility of Ferralsols that had been subject to continuous sisal cultivation in the absence of fertilizers was extremely low but that of Ferralsols that had been under 18 years of bush fallow or under secondary forest was slightly better. Acrisols that had been under continuous sisal cultivation were less depleted than the Ferralsols because of greater intrinsic fertility. A comparison of soil analytical data from the 1950s and 1960s with recent data from the same sisal fields showed that the topsoil pH of the Ferralsols had decreased by 1.5 (r2= 0.807) and that of the Acrisols by 1.2 (r2= 0.494) under continuous sisal cultivation. Thus there had been a serious decline in soil fertility under sisal cultivation, and this decline was not adequately reversed by fallowing.
Efficient Control of Spatial Variation in Yield Trials Using Neighbour Plot Residuals
Authors: Vollmann J. , Buerstmayr H. , Ruckenbauer P. 
Published: October 2008

SUMMARYThe effect of spatial variation on experimental error variance and the significance of differences between genetic entries was evaluated in five performance trials. A significant portion of spatial variation could be detected in all the experiments investigated and various neighbour plot residuals were applied to adjust for local field trends. Neighbour plot adjustment was clearly more efficient than the randomized complete block design in reducing error variance and in detecting significant differences between entries. It was also more efficient than lattice designs in trial fields exhibiting short distance trends, which could not be covered efficiently by incomplete blocks. In most experiments with long and narrow plots, longitudinal adjustment using two neighbours at each side of a test plot was superior to adjustment by only one ‘nearest’ neighbour.
Pest and Disease Hazards and Sustainability in African Agriculture
Authors: Goldman Abe 
Published: October 2008

SUMMARYSurveys of the relationship between pests and diseases and crop sustainability in several areas of Kenya, Nigeria, and other regions of Africa indicate that the production of numerous crops has declined sharply as a result of major pest and disease outbreaks, and others are threatened with major decline because of a surge in virulence of an endemic pest or disease, the introduction of a virulent exotic pest or pathogen, or because a system of control used previously has collapsed. Many of the crops that have declined were already experiencing reduced economic demand. In other cases, crop sustainability has been preserved by vigorous farmer responses or by the intervention of national and international research institutions. Most pests and pathogens, however, remain within tolerable bounds most of the time, though this often requires the use of chemical or cultural controls, or the availability of adequate land to compensate for losses. As land availability declines, more strenuous management efforts may be needed to sustain productivity.
Nitrogen Fertilization of Sugarcane in an Intercropping System with Maize and Potato in the Humid Tropical Climate of Mauritius
Authors: Kwong K. F. Ng Kee , Umrit G. , Deville J. 
Published: October 2008

SUMMARYThe competition for fertilizer nitrogen between sugarcane and a companion crop (maize or potato) grown between the sugarcane rows was studied using nitrogen-15 labelled nitrogen in three field experiments in Mauritius. The effect of the timing of nitrogen application on nitrogen recovery by sugarcane was also investigated. Not more than 15 kg ha−1 of the 120 kg ha−1 nitrogen applied to the sugarcane was taken up by the companion crop but this was compensated for by the uptake of 8 kg ha−1 nitrogen applied to maize or potato. The present recommendations for nitrogen fertilization of pure stand sugarcane were found to be applicable to sugarcane intercropped with non-leguminous food crops. Though fertilizer nitrogen uptake by sugarcane was increased by delaying nitrogen application until after the harvest of the maize and potato, this was not accompanied by an increase in sugarcane yields.
Fitting Short Duration Cowpea into a Cotton-Based Cropping System in Tanzania: Effect of Planting Pattern, Time of Planting Cowpea, and Insecticide Application to the Cotton
Authors: Myaka Fidelis A. , Kabissa Joe C. B. 
Published: October 2008

SUMMARYAn experiment to investigate the effect of planting pattern, time of planting the cowpea, and insecticide application on the yield of intercropped cotton and cowpea showed that insecticide applied to the cotton controlled cowpea pests best when the crops were planted in alternating single rows. I n wet seasons, delayed planting of the cowpea reduced its yield but its performance was better in alternating single rows than in other planting patterns. In drier seasons, cowpea yield was unaffected by time of planting and yields were similar with alternating single or double rows. Cotton yield was reduced by 47% when the planting pattern was changed to a one cotton:two cowpea row configuration.
Is Water-harvesting in Valley Floors a Viable Option for Increasing Cereal Production in Highland Balochistan, Pakistan?
Authors: Rodríguez A. , Shah N. A. , Afzal M. , Mustafa U. , Ali I. 
Published: October 2008

SUMMARYPreparation of small catchment areas on rainfed valley floor soils in highland Balochistan, Pakistan, is a low-cost method of generating run-off and increasing crop yields within the cropped areas. The effect of different proportions of water catchment area to cropped area were investigated by comparing a control treatment with the entire area planted to the crop (traditional rainfed agriculture); a 1:1 treatment, with one half of the area used for water catchment and one half for planting; and a 2:1 treatment, with two thirds of the area used for water catchment and one third for planting. Results from six seasons of trials using wheat (Triticum aestivum) showed that the 1:1 treatment had 23% higher net benefits than the control, with a 19% reduction in the coefficient of variation. The 2:1 treatment had 29% lower net benefits than the control and reduced the variation in net benefits by 8%. By contrast, four seasons of trials using barley (Hordeum vulgare) showed that the l: l treatment yielded 25% lower net benefits than the control but increased by 4% the variation in net benefits. Treatment 2:1 had 36% lower net benefits than the control and 18% more variation. Even though the gross revenue from wheat under the 1:1 treatment was less than that from the control, the reduction in total costs in the 1:1 treatment resulted in larger net benefits than the control. Water-harvesting in the valley floors is not a net yield-increasing technology. Land suitable for cultivation is limited and the increases in yields in the cropped area resulting from water-harvesting are offset by the opportunity costs of the catchment area. However, wheat grown in a 1:1 ratio of cropped to catchment area can increase farmers' income and decrease its variation. For barley, farmers are better off using their traditional management practice than giving up part of their cropped area to create water catchments.
Biomass Production, and Feed and Economic Value of Fodder Weeds as By-products of Millet Cropping in a Sahelian Farming System
Authors: Lamers J. , Buerkert A. , Makkar H. P. S. , Von Oppen M. , Becker K. 
Published: October 2008

SUMMARYWeeds are generally considered to be undesirable plants as they can cause yield losses but fodder weeds are traded as a valuable feed in Niger, Vest Africa. In vitro analyses of fodder weeds indicated that they are a suitable crude protein supplement to low quality millet stover, a major feed during the dry season. Dry matter production of fodder weeds increased with a crop residue mulch. When weeds are used as feed, farmers may generate additional income through an increased availability of energy for animal traction or for dairy and beef production. Species with the highest crude protein content, usually the most limiting factor in feed for animal production, had the highest market prices. The sale of fodder weeds may provide farmers with cash. Agricultural research programmes should be encouraged to consider the use of fodder weeds to improve both the quality and quantity of feed in the West African Sahel.
Yields of Cereal Grain and Protein
Authors: Simmonds N. W. 
Published: October 2008

SUMMARYEarlier work has shown that, in cereals in general, grain yield (Y) and protein content (P) are strongly negatively related. It is shown here that the expected positive expected relationship between grain yield and protein yield also holds, with (YP) given approximately by YP = 0.141 + 0.0969 Y. All cereal breeding in which high protein content is desired therefore faces a compromise with grain yield.
Effect of Supplementary Saline Irrigation and Applied Nitrogen on the Performance of Dryland Seeded Indian Mustard (Brassica juncea)
Authors: Dayal Bhu , Minhas P. S. , Chauhan C. P. S. , Gupta R. K. 
Published: October 2008

SUMMARYField experiments were conducted for two years to evaluate the effects of combinations of saline irrigation (ECw 14.0 ds m-1) and nitrogen levels on the yield, seasonal water use and nitrogen use efficiencies of mustard. These showed that the use of saline water can boost the growth and yield of dryland mustard and that, within certain limits, a non-saline water supply can be substituted by applying nitrogen and saline water. It is suggested that fertilizer nitrogen rates should be adjusted in relation to the supply of water and its predicted salinity.Irrigación salina y los efectos del nitrógeno en la mostaza sembrada en las tierras de secano
Effects of Crop Residue and Phosphorus Application on the Spatial Variability of Non-destructively Measured Millet Growth in the Sahel
Authors: Buerkert A. , Stern R.D. 
Published: October 2008

SUMMARYSpatial variability in soil parameters and plant growth in the Sahel are still poorly understood and may hamper the interpretation of experimental results. This paper examines whether or not soil amendments such as phosphorus and crop residues affect the variability of final dry matter production in pearl millet (Pennisetum glaucum). Within- and between-plot variation in millet growth was studied in a three-year experiment with three levels of crop residues and four levels of phosphorus. The effects of different rates of application on within-plot variation in number of tillers, number of heads, maximum tiller height, and total above-ground dry matter of single mature millet plant stands (pockets) were calculated. Above-ground dry matter, estimated non-destructively using an equation derived from numbers of tillers and heads and from maximum plant height, gave good predictions of total dry matter for a range of genotypes across the 12 treatments. Crop residue and phosphorus application reduced the number of missing pockets, leading to a more uniform stand with fewer pockets which did not produce grain. With amendments, pockets were also taller and of more uniform height but a decrease in variability of total dry matter production only became evident after standardization of the data. The results show the need for a clear definition of ‘growth variability’ in millet and indicate that both chemical and non-chemical factors govern its expression in the Sahel.Efectos de los residuos de las cosechas y del fósforo en la variabilidad del mijo
The Role of Rhizobial Biodiversity in Legume Crop Productivity in the West Asian Highlands
Authors: Keatinge J. D. H. , Materon L. A. , Beck D. P. , Yurtsever N. , Karuc K. , Altuntas S. 
Published: October 2008

SUMMARYThe numbers of bacteria and the nitrogen fixing efficiency of isolates ofRhizobium leguminosarum, R. ciceriandR. melilotiwith appropriate legume crop species were determined from soils collected from a wide range of locations in Turkey with elevations between 500 and 2200 m. For vetch and lentil nodulated byR. leguminosarum, many native rhizobia are present in most locations but they often have limited nitrogen fixation capacity. However, for chickpea nodulated byR. ciceri, relatively small numbers of bacteria and the almost universal ineffectiveness of fixation capacity point to a need for artificial seed inoculation of chickpea crops as a future agronomic priority. The wide range of bacterial numbers, considerable geographic inconsistency and generally low effectiveness of the indigenous rhizobia associated with the annualMedicagospp. suggest that inoculation would initially be a sensible precaution for all sowings.Biodiversidad del rhizobium en Asia occidental
The Role of Rhizobial Biodiversity in Legume Crop Productivity in the West Asian Highlands. III.Rhizobium meliloti
Authors: Materon L. A. , Keatinge J. D. H. , Beck D. P. , Yurtsever N. , Karuc K. , Altuntas S. 
Published: October 2008

SUMMARYThe native rhizobia capable of symbiosis with potential pasture legume crops for the west Asian highlands were surveyed and estimates made of the numbers and nitrogen fixing efficiency of isolates ofRhizobium melilotiwith a range of annualMedicagospecies. Soils were collected from 105 sites at elevations between 500 and 2200 m. Numbers of bacteria were generally adequate to permit efficient nodulation but the nitrogen fixing efficiency of three of the four host species with the indigenous rhizobia was often low. In contrast, nitrogen fixation inM. aculeatawas generally highly efficient. No overall geographic pattern in either numbers or efficiency of nitrogen fixation was evident. Substantial further research is required before annual medic crops can be successfully introduced into highland crop/livestock systems in Turkey and elsewhere in the west Asian highlands.Biodiversidad en elRhizobium meliloti
The Role of Rhizobial Biodiversity in Legume Crop Productivity in the West Asian Highlands. IV. Rhizobium ciceri
Authors: Keatinge J. D. H. , Beck D. P. , Materon L. A. , Yurtsever N. , Karuc K. , Altuntas S. 
Published: October 2008

SUMMARYThe native rhizobia capable of symbiosis with chickpea crops in the Turkish highlands were surveyed and estimates made of the numbers of bacteria and the nitrogen fixing efficiency of isolates of R. ciceri in symbiosis with an improved Turkish cultivar and a local landracc. Soils were collected from locations at elevations between 500 and 2200 m.Native rhizobia specific to the local landrace were more abundant than those specific to the improved cultivar but nitrogen fixation efficiencies of all isolates were consistently poor. Agronomic research priorities must include the identification of strains of rhizobia symbiotically efficient and ecologically persistent in highland soils. Comprehensive trials with these strains as artificial inoculants on chickpeas are required throughout the region.Biodiversidad en el Rhizobium ciceri
Experiments with Maize in Trinidad
Authors: Gibbon D. P. 
Published: October 2008

SUMMARYThe results are recorded of three field experiments, designed to investigate the effects of plant population and nitrogen fertilizer on growth and yield of maize. High yields of grain can be obtained in Trinidad provided plant populations are at least 20 000 plants per acre, nitrogenous fertilizer is added at the rate of 5–6 cwt per acre, weed and insect pests are controlled, and water is not a limiting factor at any stage of crop growth. Growth analysis has shown the importance of high leaf area indices in the production of high grain yields.