bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Choice of Groundnut (Arachis hypogaea) Varieties by Smallholders in South-east Tanzania. II. Variety × Spacing and Variety × Sowing Date Interactions
Authors: Preston S. R. , Taylor B. R. , Simons J. H. 
Published: October 2008

SUMMARYVariety × spacing and variety × sowing date trials in south-east Tanzania showed that the long-season spreading bunch groundnut variety Red Mwitunde (A. hypogaea ssp. hypogaea var. hypogaea) was less tolerant of delayed sowing and more tolerant of wide spacing than Natal Common, a short-season upright bunch variety (ssp. fastigiata var. vulgaris). The same variety × spacing and variety × sowing date interactions were detected in groundnuts intercropped with cassava (Manihot esculenta). These observations help to explain the farmers' preference for Red Mwitunde despite the higher trial yields of Natal Common.
Development and Growth of Pearl Millet (Pennisetum typhoides) in Response to Water Supply and Demand
Authors: Squire G. R. , Marshall B. , Ong C. K. 
Published: October 2008

SUMMARYStands of pearl millet were grown in three controlled environment glasshouses in which were imposed different combinations of atmospheric saturation deficit (1.5 to 2.3 kPa) and soil water content (fully irrigated and not irrigated). Consistent differences in saturation deficit (SD) were maintained throughout the experiment (100 days) but a high water table restricted differences in water supply to the first 40 days. Responses to SD and soil water were observed in some variables but not in others. Developmental processes such as the rate of leaf appearance were unaffected, whereas the efficiency for conversion of intercepted solar energy decreased by 24% and the rate at which the canopy expanded by 50%, in the driest compared to the wettest conditions.
Application of a Systems Approach in a Commodity Research Programme: Evaluating Burundi Highland Maize
Authors: Zeigler R. S. 
Published: October 2008

SUMMARYA late-maturing, high-yielding maize released for the Burundi highlands was rejected by subsistence farmers. Analysis of this variety in terms of the local cropping system shows that it offers no advantage over earlier maturing varieties when whole-system biological and economic yield and Land Equivalent Ratios are examined, while farmer risk is apparently substantially increased. The value of incorporating a ‘farming systems’ approach into national commodity research programmes in developing countries is demonstrated.
Effect of Legume Intercropping on Enrichment of Soil Nitrogen, Bacterial Activity and Productivity of Associated Maize Crops
Authors: Singh N. B. , Singh P. P. , Nair K. P. P. 
Published: October 2008

SUMMARYExperiments comparing the effects of different legume intercrops on available soil nitrogen, bacterial activity and the yield of maize over two years showed that soyabean and blackgram were more suitable for this purpose than groundnut, substantially increasing NO3and NH4concentrations and populations of active bacteria in the maize rhizosphere. This increased maize yield by 15–20% and grain protein content by 20%.
Summer Grazing Management of a White Clover-Bahiagrass Pasture: Legume Survival
Authors: Dzowela B. H. , Mott G. O. , Ocumpaugh W. R. 
Published: October 2008

SUMMARYA grazing management study involving the new white clover cultivar Osceola grown in association with Bahiagrass cv. Pensacola was conducted on wet and dry sites with and without pesticide/herbicide treatment. A combination of heavy grazing pressure and a short deferment period before grazing during the summer and autumn resulted in the largest soil seed reserves and seedling recruitment by the white clover component. However, maximum survival of plants was recorded from a combination of a short deferment period and moderate grazing pressure.A slight increase in plant survival and seedling recruitment was shown on the wet site. Survival potential was least in pasture treated with pesticide and herbicide. Heavy grazing pressure and short deferment periods appear essential for the survival of the clover component. Annual seedling recruitment from soil seed reserves was the primary mechanism of white clover survival from spring to spring in pasture associations based on tropical bahiagrass.
Intercropped Corn-Soyabean Density Studies. II. Yield Composition and Protein
Authors: Putnam D. H. , Herbert S. J. , Vargas A. 
Published: October 2008

SUMMARYIf corn-soyabean intercrops are to replace corn grown alone, maintenance of yield and improvements in forage quality are important. Total yields and inter-crop competition in corn-soyabean intercropping experiments have been discussed previously (Putnam et al., 1985). In Part II yield composition, components and protein content are presented for intercrops of varying planting patterns and corn densities. Most intercrop patterns produced more forage than sole crops compared at the same yield ratio of corn-soyabean as in the intercrop harvested mixture. At high plant density ear yields in the intercrop were increased while in sole crops they were reduced or unaffected. The increase was a result of an increased number of ears, weight per ear and kernel, and number of kernels per row in the intercrops. Increases in crude protein content over sole crop corn of 11–51% were shown for the various intercrop treatments. Crude protein yields in the intercrops were greater than either sole crop in 1981 and greater than corn and similar to soyabean in 1982, and greater than the crude protein yields expected from an equal planted area of sole crop corn and soyabean in both years. Intercrop forage quality was improved over sole corn both by the addition of protein from soyabean pods and an increased ear: stover ratio of the intercropped corn.
A Pear and Vegetable Interculture System: Land Equivalent Ratio, Light Use Efficiency and Productivity
Authors: Newman S. M. 
Published: October 2008

SUMMARYThe productivity, land equivalent ratios (LERs) and light use efficiency of a pear and radish interculture system were assessed. Pear yield was unaffected by intercropping. Relative yields for the radish component varied between 0.5–1.01 depending upon the yield index and spatial arrangement employed. This gave LER values for the system of 1.5–2.01. The overall trans-missivity of the pear canopy was 73%. A 47% reduction in photosynthetically active radiation (PAR) gave a yield reduction of 65% in terms of number of saleable radish, but did not affect total dry matter productivity. Reductions in radish yield directly beneath pear trees was thought to be due to other factors besides PAR. The total dry matter productivity of a system containing five successive radish crops was estimated at 26.25 tonnes ha−1 yr−1.
A Spot Test for Estimating Ureides in Soyabean Petioles
Authors: Glenister Richard A. , LaRue Thomas A. 
Published: October 2008

SUMMARYThe ureides allantoic acid and allantoin form a bright pink compound with acidic p-dimethylamino cinnamaldehyde. It is possible to estimate the ureide content of a soyabean petiole segment by crushing it on filter paper and developing the colour with this reagent. There is a strong correlation between the spot test and estimates from colorimetric determination of ureides. In field grown soyabeans, there was a positive correlation between the petiole ureide content during pod fill and the integrated seasonal acetylene reduction activity. The spot test can be used to identify plants with low nitrogen fixation activity.
Technology Development and the Spread of Direct-Seeded Flooded Rice in Southeast Asia
Authors: De Datta S. K. 
Published: October 2008

SUMMARYIncreased labour costs and area under irrigation, the development of modern early-maturing varieties and improved fertilizer and weed management techniques have encouraged many farmers in the Philippines, Malaysia and Thailand to switch from transplanted to direct-seeded flooded rice culture. This paper summarizes the development and spread of the technology for direct-seeded flooded rice in southeast Asia and the contribution made by research at IRRI and by national programmes. It covers research on crop establishment, varietal requirements, fertilizer management, weed control and economics and examines the advantages and disadvantages of direct-seeding compared with transplanting.
The Association of Planting Density and Plant Type in French Bean (Phaseolus vulgaris)
Authors: Tripathi S. S. , Singh P. P. 
Published: October 2008

SUMMARYFive varieties of French bean of contrasting growth habit were grown at a range of plant densities. Most varieties yielded best at 30 plants m−2, but the bush type variety Contender yielded best at 50 plants m−5. The best yield was obtained from the semi-spreading variety Rufus.
A Method for Farmer-participatory Research and Technology Transfer: Upland Soil Conservation in the Philippines
Authors: Fujisaka Sam 
Published: October 2008

SUMMARYAlthough viewed as important for on-farm adaptive research, farmer-participation has often been superficial and has not led to meaningful incorporation of farmer perspectives. This paper describes the use of a method involving the understanding of farmers' perceptions in determining priorities for research which integrates the different concerns and contributions of farmers and scientists with the transfer of technology from farmer to farmer.
Growth, Nodulation and Nitrogen Fixation in Stylosanthes: Effect of Different Root Temperatures at two Shoot Temperatures
Authors: Date R. A. , Ratcliff D. 
Published: October 2008

SUMMARYNodulated plants of Stylosanthes hamata, S. guianensis, S. humilis, S. scabra and S. fruticosa were grown in controlled environments with varied root and shoot temperatures. Measurement of dry matter and nitrogen content suggested that shoot temperature may be more important than root temperature in controlling growth and nitrogen fixation. There were strong interactions with variety. A fall in relative growth rate with increase in shoot temperature was least for S. guianensis and greatest for S. hamata and S. scabra. The optimum root temperature for growth and nitrogen fixation was approximately 30°C. Ninety percent maximum yield was achieved between root temperatures of 15–36°C for growth and 23–34°C for nitrogen fixation but varied with variety. Nitrogen fixation was more sensitive than dry weight to root temperature. The pattern of response of percentage nitrogen and nitrogen fixation efficiency reflected those for dry weight and nitrogen yields. Shoot to root ratios decreased toward the optimum root temperature then increased at the highest temperature. The reaction of varieties to root and shoot temperatures may be an important factor in determining their suitability for new regions.
On the Standard Errors and Other Moments for Ratios of Biological Measurements
Authors: Oyejola B. A. , Mead R. 
Published: October 2008

SUMMARYA method of obtaining the standard error and some other moments for the ratios of biological measurements is given, with the conditions to be satisfied by the variables used to form such ratios. Some applications of the distributional properties of the ratios in the analysis of results from experiments are discussed.
Effects of Green-stage Grazing on Rainfed Barley in Northern Syria. I. Tiller Production and Other Agronomic Characters
Authors: Yau S. K. , Mekni M. S. , Naji I. 
Published: October 2008

SUMMARYEffects of simulated and actual grazing at the tillering stage on tiller production and other agronomic characters were studied over a number of seasons at two sites in northern Syria with two local barley landraces. In general, grazing encouraged tiller production but reduced head number per unit area because of a higher tiller mortality or infertility. Seed number per head and seed weight were not affected by grazing except in one season. Grazing delayed heading and maturity and reduced plant height. Simulated and actual grazing produced similar effects on the different characters investigated.
Agronomic and Physiological Constraints to the Productivity of Tropical Grain Legumes and Prospects for Improvement
Authors: Lawn R. J. 
Published: October 2008

SUMMARYGrowth and development of the tropical grain legumes are generally highly sensitive to photo-thermal regime, so that seasonal and regional effects on phenology and yield potential can be large. Yet failure adequately to recognize and fully exploit the consequences of genotype × latitude/sowing date × density interactions has frequently constrained both agronomic and genetic advance with these species. Thus there is opportunity for short term productivity improvements through agronomic strategies which accept the implications of phenological plasticity, and seek to optimize management practices such as sowing date and sowing density, to exploit more effectively the yield potential and broaden the adaptation of existing cultivars. The greatest physiological potential for genetic improvement in the productivity of the tropical grain legumes lies not with increasing total biomass, but with increasing the proportion of bio-mass partitioned into seed, i.e. with improved harvest index (HI). There are difficulties in selecting for higher HI, including its association with phenology, although the latter provides the most powerful tool for manipulating HI in the short term. As with the cereals, more productive genotypes are likely to be characterized by reduced sensitivity to photothermal conditions, shorter growth duration, a more synchronous reproductive ontogeny, and greater HI, than is typical of traditional cultivars. Accordingly, optimal sowing densities will be higher, and crops will need more inputs, better management and more effective protection, than afforded to them in subsistence systems of production. Moreover, the increases in productivity will be achieved, at least partially, at the expense of the potential for yield homeostasis in adverse environments, and of non-seed components such as forage, fuel or tubers - attributes that are often highly valued in subsistence agriculture where many of the tropical food legumes are presently grown. Improvement programmes will therefore need to adopt strategies in particular situations which reflect local perceptions of the importance of productivity improvement relative to that of minimizing inputs and risk.
Studies on the Productivity of Egyptian Clover and Oats under Intercropping
Authors: Singh Virendra , Joshi Y. P. , Verma S. S. 
Published: October 2008

SUMMARYA trial was carried out at Pantnagar in India during 1984–85 and 1985–86 to study the productivity of Egyptian clover and oats under intercropping. Cross sowing of both the crops either at full or half seed rates and line sowing of oats in broadcast Egyptian clover was better than other intercropping systems or sole cropping in respect of herbage production, digestible dry matter yield and land equivalent ratio but crude protein yield from the mixed crops was similar to that from sole cropped Egyptian clover.
Alley Farming with Leucaena: Effect of Short Grazed Fallows on Soil Fertility and Crop Yields
Authors: Atta-Krah A. N. 
Published: October 2008

SUMMARYA long-term trial with Leucaena leucocephala was initiated in 1982 to test the sustainability of Leucaena-based alley farming compared to a conventional cropping system without trees and with continuous cultivation of maize. It assessed the integration of short grazed fallows in rotation within Leucaena alleys and their effect on soil fertility and crop yields.The various treatments had no effect on soil pH during the four-year period of the trial. The organic carbon and total nitrogen contents of the soils under conventional cropping were lower by the end of the fourth year than those under alley cropping and alley grazing treatments, whereas soil phosphorus levels were lower in the alley cropping and grazing plots. Foliage dry matter production of Leucaena under alley cropping management ranged from 6.0 to 6.7 t ha−1 a−1 under continuous cropping and reached 8 t ha−1 when alley cropping was preceded by a grazed fallow. Crop yields were consistently higher with alley cropping than with conventional cropping. Alley cropping plots in rotation with two year grazed fallows gave significantly higher crop yields during cropping years than those under continuous cultivation.
An Agronomic Evaluation of Jackbean (Canavalia Ensiformis) in Yucatan, Mexico. I. Plant Density
Authors: Kessler C. D. J. 
Published: October 2008

SUMMARYEffects of plant density were studied in field experiments carried out over four successive years as part of an evaluation of the potential of jackbean and in order to determine appropriate cultural practices for the crop. Flowering, biomass accumulation, and seed yield and its components were examined. Increased plant density led to earlier canopy development and biomass accumulation, and to increased seed yield in long growing seasons. Maximum seed yield ranged from about 1.0 to 3.8 t ha−1 between years of short and of prolonged rainy seasons, respectively. Plant size and branching were reduced at high density. Variation in seed yield was associated with differences in pod number; single seed weight and number of seeds per pod remained more constant
An Agronomic Evaluation of Jackbean (Canavalia Ensiformis) in Yucatan, Mexico. II. Defoliation and Time of Sowing
Authors: Kessler C. D. J. 
Published: October 2008

SUMMARYEffects of defoliating jackbean for forage production and time of sowing were studied in field experiments as part of an evaluation of the potential of jackbean and in order to determine appropriate cultural practices for the crop. In a long growing season, seed yield after cutting for forage was similar to that of an uncut crop but was reduced by two thirds in a short growing season. Flowering appeared to be stimulated in short days. Delayed sowing after the beginning of the rainy season progressively reduced seed yields
An Agronomic Evaluation of Jackbean (Canavalia Ensiformis) in Yucatan, Mexico. III. Germplasm
Authors: Kessler C. D. J. 
Published: October 2008

SUMMARYA field experiment was carried out to compare the performance of 18 accessions of jackbean from different origins. Plant development and phenology, final plant biomass, and seed yield and its components were evaluated. Flowering time ranged from 56 to 109 days after sowing. Bush and climbing types were identified and differences in seed yield were recorded, the largest yield occurring in a mid-season flowering accession. It was concluded that more material should be screened since germplasm introduction appears to be a promising route to larger jackbean yields in Yucatan
Intercropping Morphologically Different Cowpeas With Pearl Millet in a Short Season Environment in the Sahel
Authors: Ntare Bonny R. 
Published: October 2008

SUMMARYThe effects on yield of varying the planting date and planting pattern of morphologically different cowpea cultivars intercropped with pearl millet were studied in two field trials. The interaction between cowpea cultivars and planting date was highly significant. There was a sharp reduction in cowpea yields with late planting. Millet yields were reduced less when sown simultaneously with early cowpea cultivars than when sown with a late maturing local cultivar. Early maturing cowpea cultivars planted in closely spaced hills had less effect on millet yields than a late maturing cultivar sown in widely spaced hills. An appropriate cowpea cultivar for intercropping with peal millet would be one that was weakly competitive and that yielded both grain and fodder.
Nutritive Value and Yields of Some Forage Legumes and Barley Harvested as Immature Herbage, Hay and Straw in North-West Syria
Authors: Thomson E. F. , Rihawi S. , Nersoyan N. 
Published: October 2008

SUMMARYThe nutritive value and yield of forage legumes and barley harvested as immature herbage, hay and straw were measured in two experiments. The voluntary feed intake of peas at all stages of maturity and immature herbage from woollypod vetch was substantially lower than that of common vetch and chickling. At each stage of maturity barley was less digestible than all the forages except immature peas. Despite exceptionally cold weather in February/March 1985, yields of common vetch were higher in 1984/85 than in 1985/86 when there was less rain. Peas yielded the most hay, and chickling yielded less seed and straw than common vetch, peas and barley. Yields of digestible dry matter from straw and seed exceeded those from hay but protein yield at the two stages was similar. Mechanical baling substantially reduced the yields of baled hay but these losses would be reduced to less than 10% if the residues were grazed.
Seasonal and Clonal Differences in Shoot Extension Rates and Numbers in Tea (Camellia sinensis)
Authors: Stephens William , Carr M. K. V. 
Published: October 2008

SUMMARYShoot extension rates and numbers recorded over an 18 month period in Tanzania from three contrasting clones were analysed to determine variation between and within seasons. Clonal differences in base temperatures for shoot extension ranged from 10.3 to 14.5°C, whilst variability in the response of shoot growth rates to temperature could be ascribed to the shoot selection technique employed. Considerable clonal variation in shoot population densities occurred, with maxima ranging from 200 to 1200 shoots m−2. Total active shoot extension, the product of shoot growth rates and population densities, varied between 4 and 35 m m−2 week−1, shoot numbers being the dominant component. The implications of these results are discussed in terms of shoot measurement techniques, clonal selection criteria, yield modelling and harvesting policies.
The Determination of Bunch Yield Components in the Development of Inflorescences in Oil Palm (Elaeis Guineensis)
Authors: Breure C. J. , Menendez T. 
Published: October 2008

SUMMARYStages in oil palm inflorescence development which determine the number and weight of the fruit bunch components were identified by thinning to intervene in development and dissection of a sample of the felled palms. This showed that the ratio of female to total inflorescences and the number of flowers per spikelet were determined eight leaves prior to spikelet initiation. The number of spikelets per inflorescence was linked with the meristematic development of the primary axis. Inflorescences were prone to abortion at the onset of rapid expansion of the primary axis. The weight of the frame responded to thinning at these three developmental stages. The weight of single fruits responded shortly after the fruit set was fixed at anthesis; the response levelled off in axils of the six older leaves. At the start of an abortion phase nearly all aborted inflorescences were female, but subsequently female and male inflorescences aborted in equal proportions. Our study suggests that the number and weight of fruit bunch components are determined at a specific developmental stage but that the time to anthesis may vary considerably as a result of fluctuations in the speed of inflorescence development.
The Effect of Planting Density on the Yield Components of Oil Palm (Elaeis Guineensis)
Authors: Breure C. J. , Menendez T. , Powell M. S. 
Published: October 2008

SUMMARYYield components in oil palm were recorded in a spacing experiment comparing 56, 110, 148 and 186 palms ha−1. The higher densities reduced the number of female inflorescences (due to a decrease in the proportion of female to total inflorescences and an increase in the proportion of leaves with aborted inflorescences), the weight of the frame and the number of flowers per inflorescence. The results suggest that the production of seed per bunch can be increased by at least 15% by thinning around selected palms in seed gardens. The sex ratio and the components of flower number per inflorescence were more sensitive to competition for light than the weight of the frame and floral abortion. Components determining the oil and kernel extraction showed no response to density when assisted pollination was used, but with the successful introduction of insect pollinators, oil and kernel extraction increased with planting density as a result of an increase in fruit per bunch.