bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Plant Population and Fertilizer Nitrogen on Growth and Components of Yield of Maize Grown for Silage in Nigeria
Authors: Haggar R. J. , Couper D. C. 
Published: October 2008

SUMMARYWeekly measurements in a maize silage crop grown at three populations, each at three levels of nitrogen, showed that leaf area index, crop growth rate and total whole plant yield were greatest at the highest plant population (430,000/ha.) and lowest at the low population (47,000/ha.). At the former maximum yields of dry matter and crude protein occurred approximately seventy-five days from sowing, when the cob contribution was small. With wider spacing maximum yields occurred later. At the intermediate population (107,000/ha.), and with adequate nitrogen, sowing on the square was superior to sowing in wide rows. Nitrogen did not preferentially affect the relative dry matter yield of any growth component; plant population had a greater influence on total whole plant yield than nitrogen.
Effects of Cool Periods (15° C) at Night on Taichung (Native) No. 1 Rice
Authors: Owen P. C. 
Published: October 2008

SUMMARYTaichung (Native) No. 1 rice was grown under controlled conditions with a basic temperature regime of 30°C by day and 20°C by night. Periods of 2, 4 and 12 hours at 15°C (59°F) were imposed during darkness for the first or second 40 days, or for the first 80 days after sowing. Floral initiation was delayed by cool periods of 2 hours at night or longer, and delay from this cause was always accompanied by reduced grain yields, resulting from fewer spikelets per panicle or increased tiller sterility. This effect was not overcome when the cool periods ceased after floral initiation. Cool periods longer than 4 hours had a greater effect when they were given in the first 40 days.
A Long Term Experiment on Soil Fertility and Cotton Yield in Tanzania
Authors: Le Mare P. H. 
Published: October 2008

SUMMARYCompost or ammonium sulphate improved and maintained cotton yield for 6 years but both, together with triple superphosphate, were needed to maintain it for 9 years, after which yield declined and lime was necessary. Compost supplied necessary but insufficient phosphorus, potassium, calcium and nitrogen. Manganese toxicity was severe when potassium chloride was used on very acid soil. At suitable soil pH and with adequate phosphorus and cations, response to nitrogen was large, but for it to be most effective, calcium seemed necessary to maintain the cation: anion ratio. Without lime, yields declined with heavy rain; with it they were largest in the wettest seasons.
Estimation of the Area of Rubber Leaves (Hevea brasiliensis Muell. arg.) Using Two Leaflet Parameters
Authors: Lim T. M. , Narayanan R. 
Published: October 2008

SUMMARYA rapid, simple method is described for estimating the area of rubber leaves from two measurements on the middle and one of the side leaflets. The relationship between the area of a leaflet (A) and its length × breadth (LB), described by the expression A = 0.654 LB, does not vary between the three leaflets or between leaves of different ages, and clonal differences are slight.
Effects of Nitrogen, Phosphorus, Potassium and Magnesium on Growth of the Oil Palm
Authors: Corley R. H. V. , Mok C. K. 
Published: October 2008

SUMMARYPotassium application appeared to increase dry matter production and yield of oil palms, primarily by increasing leaf area, while nitrogen increased both leaf area and net assimilation rate. Responses to phosphorus and magnesium were harder to interpret. Production of vegetative dry matter attained a fairly constant level at the higher rates of fertilizer application, while the ratio of bunch yield to total dry matter production was little affected by fertilizer treatments. The importance of these results for oil palm breeding, and their possible value in diagnosing fertilizer requirements, are briefly discussed.
Time of Application of Nitrogen Fertilizer to Maize at Samaru, Nigeria
Authors: Jones M. J. 
Published: October 2008

SUMMARYMaize was grown for three years at three levels of nitrogen, 56, 112 and 224 kg. N ha.−1, involving altogether nine different timing and splitting treatments. Measurements were made of grain yield, plant nitrogen status and total-N-uptake, and, in one year, movement of nitrate-N in control plot soils. Where only 56 kg. N ha.−1was applied, its time of application made very little difference to yield; at higher rates of nitrogen an unsplit application as late as seven weeks was very inefficient, but only at the highest rate did a split application give any appreciable yield increase over an unsplit application to the seed bed. Consideration of the soil nitrate-N data and the long-term pattern of rainfall distribution leads to the conclusion that leaching is unlikely to be a serious problem in the nitrogen nutrition of early-planted maize.
Effects of Soil Moisture Stress on Two Varieties of Upland Cotton in Israel IV. Effects of Periods of Stress Occurrence, Correlations and Regressions
Authors: Marani A. 
Published: October 2008

SUMMARYEffects of moisture stress during different stages of cotton development were evaluated by using correlation and regression methods on data of six irrigation experiments from three different climatic regions. Significant negative correlations were found between the number of days in which soil moisture was below a threshold level, and several plant traits. Flower number was usually affected adversely by stress at the beginning of flowering; boll number, boll retention, boll weight, lint yield, lint length and seed index by stress at the end of flowering; earliness and lint fineness by stress during early boll development. Lint index, per cent and strength were affected by stress at different periods and effects of stress on lint yield were correlated with its effects on boll number, boll weight, lint length and early maturity.
Trials of Spraying and Cultural Practices on Cotton in Uganda. I. Agronomic and Spraying Implications
Authors: Davies J. C. , Wheater R. O. 
Published: October 2008

SUMMARYFour trials are described on the effects of spraying and cultural practices on pests and yields of seed cotton. Precropping with sorghum or beans after opening from a ley did not reduce yields of cotton compared to the recommended practice of ploughing a ley 6 weeks before sowing, but late ploughing and late sowing reduced yields. Nitrogenous fertilizer after a successful ley did not increase yields, but multiple sprays (up to twelve) significantly increased them over the recommended standard four spray regime, and reduced the percentage of stained seed cotton. In general cultural practices did not affect the level of pest attack, but DDT spraying gave excellent control of Heliothis armigera, while dimethoate prevented the build up of red mite (Tetranychus telarius) and gave excellent control of tea mite (Polyphagotarsonemus latus) in the multiple spray regimes.
Components Analysis of Yield Responses to Drought of Sorghum Hybrids
Authors: Blum A. 
Published: October 2008

SUMMARYDrought resistance in terms of yield and its components was studied in the field in twenty-one agronomically-adapted high-performance grain sorghum (Sorghum bicolorMoench) hybrids. Resistance was considered to be indicated by a minimal decrease in yield under stress as compared with non-stress conditions. Water stress, imposed by a decreasing amount of stored soil moisture during the growing season, decreased grain yield and number of panicles per unit area, increased the number of grains per panicle, the number of branches per whorl and the number of grains per branch, and decreased the number of whorls per panicle. Thus a compensatory effect was observed in some components for reduction in tillering under stress. Resistant hybrids performed better than susceptible ones under stress by producing a relatively higher number of panicles per unit area, and more grains per panicle branch. Susceptible hybrids performed better than resistant ones under non-stress (irrigated) conditions due to the relatively higher number of panicles per unit area and larger 1000-grain weight. Some of the implications regarding selection for yield performance under drought are discussed.
Effects of Brackish Irrigation Water and Fertilizers on Millet and Corn
Authors: Ravikovitch S. 
Published: October 2008

SUMMARYA field experiment was conducted to study the effect of irrigation with brackish water on the growth and composition of millet and corn, fertilized with various combinations of N and P. Millet irrigated with water of EC 3.30 mmho/cm. produced yields 79 to 93 per cent of the control (tap water of 0.61 mmho/cm.), depending on the N and P treatment applied. With water of EC 5.05 mmho/cm. yields equivalent to 52–72 per cent were obtained. Corn yields were 78–90 per cent of the control with irrigation water of 4.60 mmho/cm., and 55–64 per cent when irrigated with water of 7.06 mmho/cm. The N and P contents were mostly higher in plants grown on plots irrigated with brackish water.
Interactions of Genotype and Temperature on Cotton Boll Period and their Implication in Breeding
Authors: Yfoulis A. , Fasoulas A. 
Published: October 2008

SUMMARYEffects of environmental temperature on boll maturation period of cotton and the genotype response, investigated in a 3-year field experiment, showed a negative correlation between period and mean temperature and revealed genotypic differences regarding degree of temperature influence and sensibility to temperature changes. The observed genotype × temperature interactions may help cotton breeders in establishing breeding centres and in creating desirable gene combinations for wider adaptability to temperature.
Redistribution of Fungicides in Coffee Trees
Authors: Pereira J. L. , Mapother H. R. , Cooke B. K. , Griffiths Ellis 
Published: October 2008

SUMMARYUsing coffee trees sprayed with cuprous oxide and captafol it has been shown that both fungicides are redistributed within the tree canopy by rain. Under conditions of light rain fungicides are removed from upper parts of trees and redeposited at lower levels within the canopy in amounts capable of providing effective protection against coffee berry disease (CBD). With heavy rainfall, however, redeposition of fungicide at effective levels is less likely to occur. The results are discussed in relation to the success of overhead boom sprayers in controlling CBD and the observations that shoots in the upper parts of coffee trees are an important source of spores of the CBD strain of Colletotrichum coffeanum.
Nature of Competition between Weeds and Rice for Nitrogen Under Dry Land Conditions
Authors: Chakraborty T. 
Published: October 2008

SUMMARYThe nitrogen content of weeds was significantly higher than that of Dular rice-straw, but with Taichung Native I rice in winter there was no significant difference between the nitrogen in weed samples and rice plants at the tillering stage. Rice straw contained a higher proportion of nitrogen where there were three hand weedings. The total dry matter of rice was much reduced by weed competition. Weed species contained much nitrogen at the vegetative, flowering and post-flowering stages, indicating severe competition for nitrogen by weeds throughout the growth of rice under dry land conditions.
Effects of N and K Fertilizers on Cynodon IB.8 and on Soil K in Southern Nigeria
Authors: Chheda H. R. , Saleem M. A. Mohamed 
Published: October 2008

SUMMARYCynodon IB.8 was subjected to (i) various levels of N under cutting management, and (ii) various levels of K under grazing management. The results indicated significantly higher DM and CP production with 168 kg./ha. of N under cutting management, with resultant significant reduction in exchangeable and non-exchangeable soil K. Under grazing management, increased K application increased K content in the herbage, but showed a negative correlation with Ca uptake. Results indicated that the initial soil K status was adequate to supply the requirements of Cynodon, and that under grazing management the soil K status could be maintained at adequate levels to support lengthy cropping.
Competitive Effects ofCynodon dactylon, Sorghum halepenseandCyperus rotunduson Cotton and Mustard
Authors: Horowitz Menashe 
Published: October 2008

SUMMARYIn a short-term competition experiment in large containers, growth of cotton planted 3 weeks after bermudagrass (Cynodon dactylon), johnsongrass (Sorghum halepense) or purple nutsedge (Cyperus rotundus), was severely reduced; after 10 weeks of competition, weedy cotton weighed only 15 per cent of the weed-free control. Cotton sown before weeds, or weeds planted before cotton, were only slightly affected by competition. Highly significant negative correlations were found between growth parameters of cotton and weeds. Inhibiting effects, and in some cases transitory stimulation, were produced on mustard seedlings by leachate from weed-infested soil and by extracts from subterranean weed parts, suggesting that the competitive effects of perennial weeds are due to nutrient depletion and to biologically active substances.
A Rapid Laboratory Method of Assessing Susceptibility of Hevea Clones to Oidium Heveae
Authors: Lim T. M. 
Published: October 2008

SUMMARYA detached-leaf technique is described for assessing susceptibility of Hevea clones to Oidium heveae, based on intensity of sporulation. This offers a rapid, systematic method of screening clones in vitro against the disease, in place of the current nursery and field methods.
Fertility Studies on a Sandy Loam in Semi-Arid Tanzania
Authors: Anderson G. D. 
Published: October 2008

SummaryN and P fertilizers applied to maize had considerable effects over a five-year period, especially when both were given. Initial applications of 47 lb/acre/P2O5with annual dressings of 58 lb N, produced a mean yield increase of 55 per cent above the control. K gave little response in the first three years, but thereafter became more important. 1120 lb ammonium sulphate nitrate caused striking reductions in soil pH, Ca, Mg, K, total and organic P but increases in exch. Mn and soluble P. 112 lb double superphosphate increased the total and organic P and 65 lb K2O reduced organic P. Organic carbon suffered a mean loss of 33 per cent over five years. Recommendations are made regarding P2O5, N and K on this soil.
A Preliminary Survey of Cocoa Nutrition in Relation to Dieback Disease in Papua–New Guinea
Authors: Drover D. P. 
Published: October 2008

SummaryCocoa leaves were analysed for potassium, calcium, magnesium, manganese, iron, copper and zinc to assess the nutritional status of this crop in Papua–New Guinea, as part of a study into a dieback disease. Potassium and manganese contents of the leaves were generally high, whilst magnesium, iron and copper were often low. Some exchangeable cation data from soils is presented. Nutrient imbalances, toxicities and deficiencies, may make cocoa more susceptible to dieback.
Variability of Potential Evaporation in East Africa
Authors: Woodhead T. , Waweru E. S. 
Published: October 2008

SummaryMonthly and annual totals for the Penman estimate of potential evaporation have been reliably determined, for periods varying from 7 to 11 years, at 14 East African observatories. At each site, these annual and monthly totals are normally distributed, with coefficients of variation of the order of 5 and 10 per cent, respectively. Meteorological stations established for the sole purpose of supporting evaporation surveys should therefore be relocated at 5- or 6-year intervals so as to derive maximum benefit from the valuable instruments. The results of these variability analyses were applied in the evaluation of confidence limits for monthly and annual potential evaporation rates, and reference is made to recent compilations of such limits for 137 sites in Kenya and Tanzania.
Growth and Flowering of Mango (Mangifera Indica L)
Authors: Teaotia S. S. , Pandey I. C. , Upadhyay S. K. 
Published: October 2008

SUMMARYGrowth and flowering studies were made for three years on the mango varieties Dashehari Langra and Nisar Pasand. The main growth periods were March July, March July and February-November respectively, with a peak in June for Dashehari and May for Langra, but Nisar Pasand showed no such peak. Flowering on shoots within one year of the previous flowering was recorded on 73 per cent of Nisar Pasand shoots, 38 per cent with Langra and 6 per cent with Dashehari. Nisar Pasand was shown to be a regular bearer.
Heterosis and Combining Ability in Wheat under Irrigation and Moisture Stress
Authors: Sinolinding K. P. , Chowdhry A. Rehman 
Published: October 2008

SUMMARYAnalysis of a 4-parent diallel cross showed marked heterosis for yield and its components in two crosses (Mexipak × Dirk and C273 × AU49) under irrigation, while little or negative heterosis occurred under moisture stress. A large part of the genetic variation among crosses for yield, and most components of yield, was attributed to the general combining ability, indicating that the additive effects were important. Reciprocal effects and various interactions were insignificant except for kernel weight, which suggests that effective selection could be made under irrigation of genotypes adaptable to moisture stress.
Effect of Molybdenum on the Nitrogen Metabolism of Rice
Authors: Gupta D. K. Das , Basuchaudhuri P. 
Published: October 2008

SUMMARYThe application of molybdenum, as ammonium molybdate at 40 gm./ha. as a foliar spray, alone or in combination with 400 kg./ha. of N, as ammonium sulphate, significantly increased total and soluble nitrogen in the leaves, stem and grains of the high-yielding rice cultivar IR8. The significant increase in protein content of grains was associated with a corresponding increase in most of the protein-bound amino acids, viz. leucine, phenylalanine, methionine and valine, alanine, threonine, glutamic acid, serine and glycine, aspartic acid, lysine, arginine and histidine, asparagine and proline. Nitrogen itself considerably increased the protein content, but nitrogen in combination with molybdenum was more effective.
Studies on Fractional Application of Nitrogen to Hybrid Maize in India
Authors: Nair K. P. Prabhakaran , Singh R. P. 
Published: October 2008

SUMMARYField experiments conducted over 2 years to evaluate the merits of fractional application of N to hybrid maize unequivocally established its utility in circumventing leaching losses and consequently boosting grain yield. Combinations of fractional application need to be phased to minimize leaching losses and also to correspond to crop needs. Fractional application improved yields even in years when the incident rainfall was evenly distributed.
Farmers' Options in Low-Income Rural Areas of the Tropics: A Conflict of Priorities
Authors: Haswell Margaret 
Published: October 2008

SUMMARYThe world grain situation and shortages of fertilizer place the agricultural industry even more to the forefront of policy and planning in low-income tropical farming areas. Planning must be positively directed toward eliminating the major constraint of inaccessibility to markets. The narrowing of alternative agricultural opportunities as accessibility decreases is indicated for a sample of farm-family households; low-income farmers isolated from the services sector arc particularly susceptible to the constraint of ‘scarcity of season’ which in turn is aggravated by the economic cost of ill-health when this coincides with the period of heaviest agricultural work. The problem which arises is one in which farmers rely on topping-up farm income with income from non-farm activities. Unless a two-to-threefold net income over any other combination of income-earning opportunities can be assured, small-scale producers largely persist in treating farming simply as a way of life by which the subsistence needs of the family can be met without recourse to new input forms.
Effects of Close Spacing on Cowpeas (Vigna Unguiculata) in Southern Nigeria
Authors: Ezedinma F. O. C. 
Published: October 2008

SUMMARYClose spacing between and within rows significantly increased the biological and agricultural yields of cowpea without exerting clearly differential effects on the three test cultivars of different forms. It is suggested that low yields of cowpeas commonly observed in southern Nigeria could be due largely to low planting density. A six-fold increase in yield of beans can be achieved by halving the current spacing of 90 by 30 cm. provided the crop is protected from field pest damage.
Growth, Yield and Quality of Cotton under Three Water Regimes in the Sudan
Authors: Nadi A. H. El 
Published: October 2008

SUMMARYThe effects of three irrigation regimes on growth, yield and quality of cotton were investigated for two seasons in relation to earliness, quality and water-use efficiency, expressed as m. of water/kg. cotton produced. Light irrigations of cotton, at 75 mm. per irrigation every ten days, were economically better than the traditionally-accepted practice of irrigating every 14 days, and markedly better than prolonging the irrigation cycle to 20 days, mainly due to increased market value of the crop. The results also showed that irrigation intervals of 20 days, besides depressing yield, had a deleterious effect on fibre strength, though the different water regimes did not seem to affect other quality tests.
Interspecific Hybrids between Tea (Camellia sinensis) and Wilson's Camellia (C. irrawadiensis) I. Morphology and Cytology of F1 Hybrids
Authors: Bezbaruah H. P. 
Published: October 2008

SUMMARYCrosses were made between tea (Camellia sinensis L.) and Wilson's camellia (C. irrawadiensis Barua), using tea as the female parent, but reciprocal crosses were not successful. The F1 hybrids were intermediate in morphological and anatomical characters between the parents. Regular meiosis and high pollen fertility in the hybrids clearly indicate a close relationship between the parental genomes.
Effects of Inoculation and Nitrogen Fertilizer on Soybean in Western Nigeria
Authors: Kang B. T. 
Published: October 2008

SUMMARYThe effect of inoculation and added nitrogen fertilizer on soybean variety TK-5 were studied in pot and field experiments. In the former bean yields with IARI and CB 1809 inoculants were better than with Nitragin-S. In the field experiment, inoculation alone was inadequate to supply the nitrogen need of the crop, 30 kg. N/ha. being needed with inoculation, and 60 kg. N/ha. without inoculation, for maximum yield. Higher nitrogen application, combined with inoculation, increased dry matter, N-uptake, bean yield, pod number, bean weight and nitrogen content of seed. Oil content of the seeds decreased with inoculation and nitrogen application.
Effects of Low-Temperature Stress on Fertility and Fruiting of Eggplant (Solanum melongena) in a Subtropical Climate
Authors: Nothmann J. , Koller D. 
Published: October 2008

SUMMARYLow-temperature stress in eggplant during the cool season causes gradual loss of pollen fertility and leads to the development of seedless fruit, but female fertility is not similarly affected. The temperature-induced male sterility is transient, and full pollen fertility is regained with normal seed development, as temperature conditions improve.
Yield and Yield Components of Six Sweet Potato (Ipomoea batatas) Cultivars I. Contribution of Yield Components to Tuber Yield
Authors: Lowe S. B. , Wilson L. A. 
Published: October 2008

SUMMARYTotal yield and yield components (tuber numbers and mean tuber weights) of six local sweet potato cultivars were compared in wet and dry season crops. There were significant negative correlations between tuber number and mean tuber weight in five of the six cultivars, and positive correlations between these yield components and total yield, suggesting that cultivars may be grouped into ‘tuber number-tuber weight’ and ‘tuber weight’ types, as well as a ‘random type’ in which yield is related to neither component. Marketable yield tended to be directly related to both components, and cultivars with lower tuber numbers usually produced a higher percentage of marketable yields. The significance of these findings for sweet potato yield improvement is discussed.