bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Temperature and Photoperiod on Bulbing of the Common Onion (Allium Cepa L.) Under Arid Tropical Conditions of the Sudan
Authors: Abdalla Abdalla A. 
Published: October 2008

SummaryUnder the arid tropical conditions of the Sudan, where seasonal variations in photoperiod are small but where temperatures are high, there is evidence from the performance of both local and introduced onion varieties that temperature has considerable influence on bulbing. The onset of bulbing does not prohibit the emergence of bladed leaves under such high temperature conditions. The size of the onion plant may be an important factor in the bulbing response under conditions of high temperature and small variations in photoperiod.
Summer Cropping Groundnuts in North Bihar
Authors: Thakur C. , Chowdhury S. K. 
Published: October 2008

SummaryA field experiment was conducted to see if a successful crop of groundnuts can be raised in North Bihar (India) during summer in rotation with paddy. The experiment was designed to find a suitable variety, and the best time of sowing and digging. Three promising varieties of groundnut, one early-bunch and two late-spreading types, were included in the test. Emergence and flowering were rapid in the early-bunch variety as compared to the two late-spreading varieties. Though flowering was less in the bunch variety, the percentage of mature kernels was higher. The earlier the sowing and the later the digging, the greater was the pod yield in all cases. On the basis of these results and other practical considerations, the best combination seems to be to sow the early variety AK 12-24A about 15 January and to dig about 22 June.
Effects of Shade on the Structure and Chlorophyll Content of Arabica Coffee Leaves
Authors: Hollies M. A. 
Published: October 2008

SummaryLeaves of Coffea arabica L. were sampled from an artificial shade trial to examine the effects of two levels of shade, compared with full exposure, on size, structure and chlorophyll content. A grid was designed for the rapid measurement of leaf areas in the field, and individual leaf areas were found to increase progressively with shading. Since dry weight per leaf was not affected, an increase in specific leaf area was entailed. Leaf size varied greatly with season of formation, a wider range occurring in selection N39 than KP162, but the reasons for the variation were not clear. Neither lamina thickness nor proportion of palisade tissue varied with shade treatment. Chlorophyll per unit weight increased with shade in KP162 but with N39 was only greater under dense shade. Chlorophyll per unit area did not alter with shade, but N39 had significantly more chlorophyll than KP162 on both a weight and an area basis.
Premature Death of Groundnut Plants in Northern Nigeria
Authors: Perry D. A. 
Published: October 2008

SummaryPremature wilting and death of groundnut plants in Northern Nigeria was caused mainly by termites excavating the xylem tissue of the root. Lepidopterous larvae which damaged the crown of the plant were a less common cause. Occasional wilted plants had discoloured vascular systems from which Pythium myriotylum was consistently isolated. Wilting was also caused by mechanical damage inflicted during weeding operations. Complete severance or blockage of the water-conducting tissue of the primary root did not result in immediate death of plants, because the pods and pegs were able to absorb sufficient moisture to maintain the leaves above permanent wilting point until the onset of the dry season.
Effects of Lindane and Carbaryl on Insects, Soil and Plant Nitrogen, and Grain Yield of Rice
Authors: de Datta S. K. , Ayyangar R. S. , Magbanua J. T. 
Published: October 2008

SummaryExperiments were conducted during three crop seasons to determine the effects of lindane and carbary1, applied to the irrigation water or incorporated in the soil, on the control of insects, on the nitrogen status of the soil and plant, and on grain yield of lowland rice. In two crop seasons the highest grain yield was obtained from three applications of lindane to the irrigation water and carbaryl sprays at 7- to 10-day intervals, and in the third season from 20 kg/ha. carbaryl incorporated in the soil without any lindane treatment or carbaryl spray. In two seasons, soil-incorporated carbaryl at 20 kg/ha. active ingredient gave a significantly higher yield than the no-insecticide control, and in one season the increase in grain yield was just below the significant level. Most of the grain yield increase with 20 kg/ha. carbaryl incorporated into the soil was caused by better control of stem borer and leafhopper and a significant reduction in virus infection.
The Races of Sorghum in Nigeria: their Distribution and Relative Importance
Authors: Curtis D. L. 
Published: October 2008

SummarySorghum is the principal foodcrop grown in Northern Nigeria. A survey of local varieties grown during the rains was carried out in 1958 and the 821 samples collected were assigned to seven morphologically distinct races, of which four are important. Varieties belonging to the Guinea race, with loose, open panicles, are mainly cultivated in high rainfall areas south of latitude 11°30′N. Further north, three races, Kaura, Farafara and Chad are grown in the dry Sudan Savanna zone. Varieties of these races have compact panicles and bulging grains. Estimates of the contribution made by each of the four major races indicate that the Guinea race accounts for nearly 50 per cent of the total sorghum production in Northern Nigeria.
Tolerance of Three Olive Varieties to Soil Salinity in Israel
Authors: Bidner-Barhava Nehama , Ramati B. 
Published: October 2008

SummaryAn investigation was undertaken on the relative tolerance to salinity of the olive varieties Manzanillo, Souri and Sigoise in the arid zone of Israel (Negev), in an experimental grove of the Jewish National Fund, using 11-year-old trees that were grown on saline and non-saline soils under irrigation with sewage water. Manzanillo was the most sensitive to salinity, yields and development of trunk, crown and root system all being adversely affected. Sigoise was the most tolerant to salinity and vegetative development was not impaired at all. Souri was intermediate in sensitivity to salinity. In spite of the susceptibility of Manzanillo it is preferred because of its high yield, which was greater even on a saline soil than yields of the other two varieties on non-saline soil.
Nitrogen Fixing Capacity of some Nigerian Legumes
Authors: Oke O. L. 
Published: October 2008

SummaryThe fixation of nitrogen in root nodules of pigeon pea, Centrosema pubescens and Styloxanthes gracilis were studied, and the transfer of nitrogen to other parts of the plant. Fixation reached a maximum of 14·5, 10·3 and 4·6 mg. per day per plant respectively, and the rate of transfer of nitrogen from the nodules was at a high constant rate throughout the experimental period. With pigeon pea and Centrosema younger plants seem to be more efficient fixers of nitrogen than older on, but the reverse was true with Styloxanthes.
Comparisons Between Strains of Eragrostis Curvula in South Africa
Authors: Leigh J. H. 
Published: October 2008

SummaryTwenty strains of Eragrostis curvula, together with E. plana, Chloris gayana and Digitaria smutsii, have been compared on the basis of (a) herbage yields and (b) nitrogen, phosphate and potash composition and yield, from broadcast stands in a randomized block experiment over two seasons. The strains of E. curvula were grouped into types for which the names Curvula, Robusta Blue, Robusta Green, Robusta Intermediate, and Chloromelas were used. Significant differences were demonstrated in herbage yield between certain of these types, but there were no clear differences in nitrogen content. Chloris, Digitaria and the three Robusta types had the highest phosphate and potash content, whereas the Chloromelas type and E. plana were intermediate and the Curvula type was lowest in these constituents. Robusta Green, Robusta Intermediate and Curvula types had the highest nitrogen yield, Robusta Green and Robusta Intermediate types the highest phosphate yield, and Robusta Intermediate and Robusta types the highest yield of potash. The superiority of types other than Curvula (Ermelo and Tanganyika strains), and the need for research on the types, has been demonstrated.
A Computer Programme for the Calculation of Confidence Limits of Expected Rainfall
Authors: Walker J. T. , Rijks D. A. 
Published: October 2008

SummaryEssential features are described of a computer programme, written in F.A.S., for the evaluation of 1 : 1 and 4 : 1 confidence limits of expected ‘twenty-day’ totals of rainfall. The paper deals briefly with the availability and utility of the programme to agricultural research workers in Africa.
Problems in Plant Pathology and Entomology Field Trials
Authors: Freeman G. H. 
Published: October 2008

SummaryThe problems arising in field trials in plant pathology and entomology are considered under five headings: (1) experimental design, (2) conduct of experiments, (3) records, (4) analysis and (5) interpretation. Solutions to the problems are not always given, but it is useful to recognize their existence. Examples are given from a wide range of crops
Calculating the Weight of Young Coffee Trees from Non-Destructive Observations
Authors: Wormer T. M. , Ngugi D. 
Published: October 2008

SummaryThe weights of the branches, stems and roots of two or three year oldarabicacoffee trees were compared with the diameters of the stumps or stems and with the heights of the trees. No formula could be derived, relating the weight of the plants to one or more non-destructive observations, which was valid for all three treatments to which the trees had been subjected, i.e. stripped of crop when two years old, cropping when two years old, and bearing a crop when three years old. Bearing a crop when two years old resulted in thin, light stems and a poor root system.
Flowering, Pollination and Pod Formation in Bambara Groundnut (Voandzeia Subterranea) in Ghana
Authors: Doku E. V. 
Published: October 2008

SummaryAlthough bambara groundnut (Voandzeia subterranea) is an important pulse crop in Africa and particularly in Ghana, information on the crop is not only very limited but conflicting, especially as regards flowering and mode of pollination. Both self- and cross-pollination can take place in varying degrees, depending on variety or strain, and this is brought about by two species of ants, Pheidole megacephala and Monomorium pharaonis, without which pollination might be severely limited or prevented altogether. The extent of cross pollination may be greater in varieties or strains with a more open habit, i.e.. varieties resembling the wild uncultivated ancestors, whereas the bunch cultivated types are more likely to be self-pollinated. It is suggested that varieties or strains may show differences in their ability to cross with one another.
Effects of Nitrogen and Spacing on Castor Bean in Sandy Soils in Egypt
Authors: El-Hamidi A. , Moursi M. A. , Ahmed S. S. 
Published: October 2008

SummaryCastor beans grew well in sandy soils in U.A.R. where field crops had previously failed to produce good yields. Calcium nitrate up to 300 kg. per feddan resulted in increased yields of seeds and oil in a two-year experiment. Better yields were obtained by increasing the number of plants up to 3 per hill at distances of 45 cm. apart. The oil percentage and other properties were not influenced by nitrogen fertilizers or plant density.
Long Term Experiments with Fertilizers and Manures on Sugarcane in India
Authors: Singh Ambika , Roysharma R. P. 
Published: October 2008

SummaryThe yield and soil data are presented of four long-term experiments on sugarcane at Muzaffarnagar (Uttar Pradesh), Anakapalle (Andhra Pradesh), Padegaon (Maharashtra) and Shahjahanpur (Uttar Pradesh). On soils where phosphorus and potash were not limiting, application of ammonium sulphate over 14 years at Muzaffarnagar and Anakapalle gave higher yields than those obtained by application of farmyard manure, and the fertility status of ammonium sulphate plots was in no way inferior to plots treated with farmyard manure. When phosphorus was also limiting, the application of a basal dose of compost on black cotton soil maintained yield levels. There was a steady decline in yields of cane in plots which received a dressing of ammonium sulphate without any basal dose of compost, but when N.P.K. equivalent to the compost were added the yields were equal to those from plots receiving compost. Thus the effect of compost is explanable on its nutrient content rather than on its effect on physical properties of the soil. In Shahjahanpur there was a decrease in cane yield as the experiment progressed, but the decline in yield in ammonium sulphate treated plots was of the same magnitude as from the plots receiving no dressing of ammonium sulphate. By changing the cane variety and the rotation simultaneously, the yield from all plots went up but subsequently showed a declining tendency.
Responses of Grasses and Legumes to Fertilizer Treatments in Nigeria
Authors: Tewari G. P. 
Published: October 2008

SummaryA two-year field investigation was conducted to evaluate the response of two varieties of Guinea grass and two leguminous species, grown alone and in mixtures, to fertilizer treatments. Styloxanthes gracilis and a Guinea grass variety ‘Liconi’ were observed to be superior to others in their yielding ability. Styloxanthes and the Liconi Guinea grass appeared to be mutually compatible at particular seeding rates. Sabi Guinea grass and Centrosema pubescens were the poorest performers under all conditions. Findings also suggested that the adapted and mutually-compatible legumes and grasses could be grown in mixture under tropical conditions, and high yields obtained without the use of expensive nitrogenous fertilizers.
Growth Analysis of Perennial Grasses in Tropical India I. Herbage Growth in Pure Grass Swards
Authors: Singh R. D. , Chatterjee B. N. 
Published: October 2008

SummaryHerbage production from twelve perennial grasses was analysed under two frequencies of defoliation. There were differences in the speed of establishment from seed, Heteropogon contortus, Pennisetum pedicellatum and P. polystachyon being most rapid. Once the grasses were established, the highest yields were obtained from Andropogon gayanus and Brachiaria brizantha and the lowest from Paspalum notatum. Yields were higher at the lower frequency of cutting. There were large differences in production throughout each year, with yields during winter and the dry season (November to April) only about one-tenth of those obtained in the rainy season. A. gayanus, B. brizantha, Chloris gayana and Dichanthium caricosum gave higher yields than other species during winter. Variations in yield between species could generally be ascribed to variations in the extension of leaf area, although some species maintained high net assimilation rates during unfavourable growth periods.
Growth Analysis of Perennial Grasses in Tropical India II. Herbage Growth in Mixed Grass/Legume Swards
Authors: Singh R. D. , Chatterjee B. N. 
Published: October 2008

SummaryThe perennial grass Pennisetum polystachyon was grown alone or in mixture with the indigenous legumes Atylosia scarabaeoidesand Clitoria ternata and the exotic species Calopogonium mucunoides, Centrosema pubescens and Stylosanthes gracilis. Only the last two persisted for more than one or two years. Mean annual yield from the mixture containing Centrosema was 61 to 65 q./ha., of which 20 per cent was legume herbage. The protein content of grass was about 3 to 6 per cent and of legumes 10 to 14 per cent. Mixed swards produced as much protein as in a previous experiment where pure swards of Pennisetum polystachyon received 44. kg./ha. of nitrogen in fertilizer form. Soil nitrogen increased under the Centrosema mixture and yields from the mixture increased during the experiment. Yields of grass herbage from the mixtures were generally lower than those of the grass swards. The reduction in yield of grass grown in mixed swards was mostly due to decreases in the area of foliage rather than to reductions in net assimilation rate.
Agronomic Aspects of Broad Beans (Vicia Faba L.) Grown in the Sudan
Authors: El Saeed E. A. K. 
Published: October 2008

SummaryField experiments in three successive growing seasons (1963–66) studied effects of variety and plant density on yield components of broad beans. In 1963/64 total seed yield of a local variety (Beladi), increased with increasing seed rates from 70 to 280 lb per feddan, but yield increment diminished beyond 140 lb. The same results were obtained with Beladi and Rebaya 34 in 1964/65 and 1965/66, but Rebaya 34, yielded less than Beladi at all seed rates. Growth analysis revealed that Rebaya 34 had greater growth rate at the beginning of the season, due to its relatively large seed size, but eventually Beladi overtook it. Maximum pod growth in both varieties occurred when leaf dry weight was declining. The proportion of dry matter was greater in pods of Beladi than Rebaya 34 because of more sinks in the former variety. The present seed rate of 70 lb per feddan seems to be suboptimal and factors affecting establishment and/or effective leaf area at the time of pod growth are detrimental to the final yield.
Studies on the Nutrient Status of Some Coconut Soils in Ceylon 10. Minor Soil Series and Conditions in the Chilaw District
Authors: Santhirasegaram K. 
Published: October 2008

SummaryThe results are reported of pot experiments, using indicator plants, on the nutrient status of three soils varying in fertilizer history. All soils were deficient in nitrogen, and in the absence of added nitrogen yield of grass was below 10 per cent of the potential. All forms of nitrogenous fertilizers were equally effective. All soils showed an acute deficiency of phosphorus at the early stages of the experiments, but with time, and depending on the amount of fertilizer applied in the past, the response to phosphorus decreased. There was little or no response to potassium at the early stages of the experiments, but relative yields later fell linearly with time. Calcium was necessary in small quantities as Ca(OH)2, CaCO3 to correct soil acidity, particularly for legume growth. Magnesium increased yields at the latter stages of the experiments. Sulphur was deficient in all soils. The soils had adequate amounts of the minor nutrients. A cheap and quick technique was used with simple and factorial designs to obtain preliminary information, as a guide to planning detailed field experiments on the nutrient requirements of perennial crops like coconuts and other intercrops.
Potential Productivity of Tropical Perennial Crops
Authors: Corley R. H. V. 
Published: October 2008

SummaryLarge yields and dry matter production rates have been recorded for tropical perennial crops, despite the fact that little research has been done on most of them. Considerable increases in productivity should still be possible, since the potential energy fixation rate for such crops is estimated to be about 1.2 TJ ha−1a−1. The dry matter equivalent of this energy varies between species; the oil crops and rubber, in particular, have large energy contents in their respective economic products. Hot leaf temperatures appear to limit productivity in some crops, while unfavourable partitioning of assimilates limits yield at the large leaf area indices necessary to maximize dry matter production. Respiratory losses are large in these crops and selection for smaller respiration rates could lead to considerable improvements in their net productivity.
Effect of Rhizobium Numbers on Nodulation and Dinitrogen Fixation in Groundnut
Authors: Nambiar P. T. C. , Ravishankar H. N. , Dart P. J. 
Published: October 2008

SummaryGlasshouse studies have shown that nodulation and dinitrogen fixation in groundnuts grown in a sand/vermiculite mixture increased with an increase in Rhizobium numbers inoculated onto each seed. Cultivars Robut 33-1 and TMV 2 required 106 rhizobia seed−1 for maximum nodulation and dinitrogen fixation, while cv. Kadiri 71-1 required larger numbers.
Nutrient Uptake by Intercropped Maize and Cowpeas and a Concept of Nutrient Supplementation Index (NSI)
Authors: Wahua T. A. T. 
Published: October 2008

SummaryAccumulation curves for N, P, K and Ca were determined for intercropped maize and cowpeas given different fertilizer combinations. Both species competed for these four elements, with cowpeas suffering relatively more than maize. A concept of a Nutrient Supplementation Index (NSI) was developed to aid studies on fertilization of crop mixtures. Using this index, it was estimated that an additional 9.7, 24.0, 9.7 and 30.6% of N, P, K and Ca, respectively (based on the requirement of sole-crop maize), might be needed to satisfy the combined needs of a 1:1 row maize–cowpea intercrop.
Effect of Soil Crusting on Seedling Growth in Contrasting Sorghum Lines
Authors: Soman P. , Jayachandran R. , Peacock J. M. 
Published: October 2008

SummarySeedling growth from sowing to emergence of two crust tolerant and two susceptible sorghum genotypes is described. Tolerant genotypes had longer mesocotyls with faster growth rates than the susceptible genotypes. The mechanism involved in crust tolerance appears to be that of avoidance by fast growth.
Site-factor Influence on Barley Response to Fertilizer in On-farm Trials in Northern Syria: Descriptive and Predictive Models
Authors: Jones M. J. , Wahbi A. 
Published: October 2008

SummaryThe effects of site and rate of application of fertilizer on the grain and straw production of barley were investigated in 75 trials on representative farmers' fields. Grain and straw production were strongly but curvilinearly correlated with growth-period rainfall over the range 136–568 mm, almost irrespective of soil type, previous crop or fertilizer rate, and responded positively to applied nitrogen and/or phosphorus in 74 of the trials. Responses to nitrogen increased and those to phosphorus decreased with increasing rainfall. Yields tended to be lower but responses to nitrogen were higher where barley followed barley and were influenced by the availability of phosphate and mineral nitrogen in the soil at planting time.These results are summarized in regression equations, which express yield quadratically in terms of fertilizer rates, seasonal rainfall and their interactions over the full 75-trial data set and within representative sub-sets. The wide differences in crop response to fertilizer highlight the problem of recommending fertilizer rates for a low and variable rainfall environment. Simple second-order multiple regressions for different geographical areas, rainfall zones, crop rotations etc., based on mean rainfall values, account for around 40% of the variance in yield response to nitrogen and phosphorus fertilizer; only a small proportion of the remaining variance appears attributable to rainfall variability. Alternatively, yield may be expressed as a function of fertilizer rate and rainfall using rainfall probability values derived from long-term records. This can be used to estimate the probabilities of predetermined yield responses for specified sites and fertilizer rates and to produce maps of those probabilities.