scispace - formally typeset
Search or ask a question

Showing papers on "Sowing published in 1991"


Journal ArticleDOI
TL;DR: Treatment of peanut seed with B. subtilis was associated with improved germination and emergence, increased nodulation by Rhizobium spp.
Abstract: Bacillus subtilis, when added as a seed treatment, consistently colonized the roots of peanut plants at rates exceeding 10 4 colony-forming units (cfu) per gram of root tissue when evaluated 120 days after planting. Yield increases from 1982 to 1985 ranged from −3.5 to 37%, with only two incidences of negative responses in 24 tests. Peanuts responded most favorably to the bacterial seed treatment when subjected to stresses, such as limited water availability, poor rotational practices, or cool soils, caused by early plantings. Treatment of peanut seed with B. subtilis was associated with improved germination and emergence, increased nodulation by Rhizobium spp., enhanced plant nutrition, reduced levels of root cankers caused by Rhizoctonia solani AG-4, and increased root growth. The means by which B. subtilis may affect yield in peanuts are multiple and are not operative at the same time, making predictions of degree of yield responsiveness difficult

232 citations


Journal ArticleDOI
TL;DR: Examination of phenotypic variation among populations, among families, within families, and the homogeneity of variances within families for morphological and life history characters of an alien, self-pollinating annual grass, Bromus tectorum, suggests that families differ in the capacity for phenotypesic response to environmental variation.
Abstract: For Bromus tectorum, an alien annual grass now widespread in western North America, we assessed the sensitivity of the phenotypic expression of populational differences in phenology and demography to variation in plant density. Plants were grown in an unheated glasshouse from seeds collected from six habitat types located along a moisture-temperature gradient. Survival to flowering was high with a mean overall survival of 91%. Survival was highest among plants from the coolest, most mesic site. Time to first flowering decreased at the higher sowing density and was dependent on seed source. Plant dry weight and average seed production was lowest within high density plots; the magnitude of this reduction was significantly dependent on seed source. Individual seed weight was also dependent on the interaction of seed source and sowing density. Seed weight did not vary as much as seed number or plant weight in response to density. Differences among sources in hierarchies of plant size and seed production were detected at low sowing densities. The degree of inequality in the distributions of plant size and seed number increased at high density.

202 citations


Journal ArticleDOI
TL;DR: The number of seeds per unit area is an important yield component in soybean; however, the mechanisms responsible for the regulation of this yield component are not well understood.
Abstract: The number of seeds per unit area is an important yield component in soybean [Glycine max (L.) Merr.]; however, the mechanisms responsible for the regulation of this yield component are not well understood. Field experiments were conducted at Lexington, KY (3 yr), and at Taian, China (1 yr), to investigate the relationship between net canopy photosynthesis and seeds per unit area using genotypes with differences in individual seed growth rates (SGR). At Lexington, shades (30 and 63% reduction in insolation) were placed over plots from growth stage R1 until maturity to create differences in canopy photosynthesis. Planting date (early and late) and row spacing (wide and narrow) were used at Taian to create differences in canopy photosynthesis

178 citations


Journal ArticleDOI
TL;DR: Seed treatments with Bacillus cereus UW85 increased nodulation of soybeans in three field seasons and in three different sterilized soils in the growth chamber, indicating that the increase in nodulation was not dependent on the soil flora.
Abstract: Seed treatments with Bacillus cereus UW85 increased nodulation of soybeans in three field seasons and in three different sterilized soils in the growth chamber. In the field, 28 and 35 days after planting, UW85-treated plants had 31 to 133% more nodules than untreated plants. From 49 days after planting until seed harvest, there were no significant differences between nodulation of UW85-treated plants and untreated control plants. In the growth chamber, in sterilized soil-vermiculite mixtures, at 28 days after planting, UW85 seed treatments enhanced nodulation by 34 to 61%, indicating that the increase in nodulation was not dependent on the soil flora.

121 citations


Journal ArticleDOI
TL;DR: Although forage maize (Zea mays L.) is grown extensively on livestock operations, most management studies in the USA focus on grain production.
Abstract: Although forage maize (Zea mays L.) is grown extensively on livestock operations, most management studies in the USA focus on grain production. Field studies were conducted in New York to evaluate dry matter (DM) yield and forage quality responses of commercial hybrids to planting dates and densities. Six hybrids were planted on 25 April, 9 May, and 23 May and thinned to 5.0, 6.5, and 8.0 plants m −2 in 1988 and 1989

93 citations


Journal ArticleDOI
TL;DR: While variation for dry matter production existed within the standard cultivars, it was not adequate or consistent enough to be of value in breeding.
Abstract: Increased early vigour and vegetative biomass at anthesis should lead to yield improvements in wheat. Fifteen introductions were compared with five standard cultivars in Western Australia at Wongan Hills in 1988, and Wongan Hills, Merredin and Esperance in 1989 to identify useful parents for their early vigour and biomass production. Two times of sowing were included at Wongan Hills in 1989. Dry matter production was measured at all sites except Esperance at the early vegetative stage (49 to 55 days after sowing), late vegetative stage (56 to 75 days after sowing), and at anthesis. Some introductions were more vigorous in the vegetative stages, and produced more biomass at anthesis than the standard cultivars. Experiments under irrigated, non-stress conditions showed these lines produced leaves and tillers more quickly than the standard cultivars. The full growth potential of these lines may not have been expressed fully due to environmental limitations. While variation for dry matter production existed within the standard cultivars, it was not adequate or consistent enough to be of value in breeding. Dry matter production at the vegetative and anthesis stages was correlated significantly with grain yield in 1989, but not in 1988. Broad sense heritabilities for dry matter production at the three stages were generally high, averaging 72, 73 and 69% for early vegetative, late vegetative and anthesis dry matter production respectively. The importance of assessing the value of early vigour and biomass in breeding populations is discussed.

75 citations


Journal ArticleDOI
TL;DR: There were major effects of temperature on germination rate and germination percentage for all 20 legume entries.
Abstract: (...) Our objectives were to compare the influence of different temperatures on the germination percentage and germination rate index of 20 forage legumes. Legume seedlings were grown for 10 d in polyethylene growth pouches placed in germination chambers and held in the dark at constant temperatures of 10, 15, 20, 25, or 30 °C. There were major effects of temperature on germination rate and germination percentage for all 20 legume entries. If we define satisfactory germination as 80% germination at 10 d after planting, 18 of the 20 entries had satisfactory germination at some temperature between 10 and 30 °C (...)

70 citations


Journal ArticleDOI
TL;DR: In this paper, the effect of two seed rates and two row spacings on the pattern of water use and water use efficiency of no-till winter wheat (Triticum aestivum L.).
Abstract: Management practices are required in rainfed agriculture of western Canada to reduce early season water evaporation from soil relative to loss by transpiration. The objective of this study was to measure the effect of two seed rates and two row spacings on the pattern of water use and water use efficiency (WUE) of no-till winter wheat (Triticum aestivum L.). Nine field trials were conducted on Udic Haploboroll and Mollic Cryoboralf soils in Saskatchewan from 1987 to 1989 (...)

68 citations


Journal ArticleDOI
TL;DR: In this paper, the effect of seed rate and row spacing on grain yield and yield components of no-till winter wheat were evaluated in 21 trials conducted in Saskatchewan from 1986 to 1988.
Abstract: A snow management system, which utilizes no-till seeding into standing stubble immediately after harvest of the previous crop, has permitted the expansion of winter wheat (Triticum aestivum L.) production in western Canada. The effect of seed rate and row spacing on grain yield and yield components of no-till winter wheat were evaluated in 21 trials conducted in Saskatchewan from 1986 to 1988. Two winter wheat cultivars were evaluated in eight of the trials. The relationship between grain yield (Y) and seed rate was best described by a modified inverse polynomial : Y=uSR(1-SR/566)/(SR+u/104) where u represents the upper limit of yield when seed rate is not limiting (...)

68 citations


Journal ArticleDOI
TL;DR: In field experiments, bio-priming and coating with Pseudomonas fluorescens AB254 consistently protected sweet corn seeds from preemergence damping-off caused by Pythium ultimum Trow.
Abstract: In field experiments, bio-priming and coating with Pseudomonas fluorescens AB254 consistently protected sweet corn (Zea mays L.) seeds from preemergence damp- ing-off caused by Pythium ultimum Trow. The bio-priming seed treatment was evalu- ated under various disease pressures and with seeds of three sweet corn genotypes: shrunken-2 supersweet (sh-2), sugary enhancer (se), and sugary (su). While no damping- off occurred in the su sweet corn, bio-priming protected sh-2 and se sweet corn seeds at a level equivalent to that obtained by treatment with the fungicide metalaxyl. Bio- priming increased seedling height of all three sweet corn genotypes at 4 weeks post- planting. Coating of sweet corn seeds with P. fluorescens AB254 provided an equivalent degree of protection from damping-off under all but the most severe conditions.

66 citations


01 Jan 1991
TL;DR: In this article, the results of soil fertility trials carried out at Holetta and Ginchi showed that application of 50 percent of the total N at sowing and the rest at full tillering stage significantly increased grain yield as well as protein content of wheat.
Abstract: In soil fertility trials carried out since 1966 at Holetta, on red and black soils, both nitrogen and phosphors significantly affected wheat grain yield. The highest wheat yields were obtained with the application of 60 kg N and 60 kg P2O5/ha. Farmyard manure (FYM), bone meal, and blood meal were effective sources of plant nutrients. The application of 12 t/ha of FYM gave yields comparable to 100 kg/ha of diammonium phosphate. Green mauring improved soil fertility status and increased the efficiency of applied nutrients. Yield increased three-fold without the use of fertilizer when a green manure crop such as vetch was plowed under at the flowering stage. Response to N and P were higher on the vetch-wheat plots, indicating increased efficiency as a result of green manuring. Studies on N application timing on Nitosols at Holetta and Vertisols at Ginchi showed that application of 50 percent of the total N at sowing and the rest at full tillering stage significantly increased grain yield as well as the protein content of wheat.

Journal ArticleDOI
TL;DR: N from a legume cover crop can replace or substantially reduce fertilizer N requirements in corn production systems in the Appalachian region, and biological immobilization of N appeared to be reducing N uptake by corn grown in rye residues.
Abstract: Winter annual legume cover crops can reduce nitrogen (N) fertilizer requirements and provide a water-conserving mulch to a subsequent crop. A two-year study was designed to test cover crops of rye (Secale cereale L.), hairy vetch (Vicia villosa Roth), and big/lower vetch (Vicia grandiflora Scopoli) for their ability to produce N and to conserve soil water for a succeeding corn (Zea mays L.) crop. We measured the cover crops' biomass, N yield, carbon (C) to N ratio, and influence on a subsequent corn crop grown under two tillage regimes (disk tillage or no-till). Nitrogen content in cover crop biomass at time of corn planting ranged from 37 to 187 kg/ha. Pure stands of hairy vetch and a mixture of hairy vetch plus bigflower vetch had generally higher N yields, and rye was lowest. Rye growing in association with hairy vetch had lower C:N ratios than rye growing alone. Legume C:N ratios remained generally unchanged from earlier (disked) to later (herbicide) kill dates, but total N and biomass typically increased in the last 2 to 3 weeks before corn planting. Soil water retention was affected by tillage in some cases; no-till was superior to disk incorporation in each case where there was a tillage effect. Cover crops with greater biomass resulted in greater soil water retention. Among cover crops, uptake ofNby corn was greater from hairy vetch or hairy vetch plus bigflower vetch mixture. Biological immobilization of N appeared to be reducing N uptake by corn grown in rye residues. Corn in nonlegume plots fertilized with 140 or 210 kg N/ha took up more N than corn following legumes, but there was no corresponding yield increase. Corn biomass yields following the cover crops ranged from 8.6 to 18.0 Mg/ha with no additional fertilizer N. In the second year of the study, average corn yields following hairy vetch (15.3 Mg/ha) or hairy-bigflower vetch mixtures (16.4 Mg/ha) were not statistically different from corn yields produced by a 140 kg N/ha fertilizer rate (17.4 Mg/ha). These results suggest N from a legume cover crop can replace or substantially reduce fertilizer N requirements in corn production systems in the Appalachian region.

Journal ArticleDOI
TL;DR: Redvine germination was not affected by solution pH, whereas germination did not occur when osmotic stress of as little as -200 kPa was applied to seed.
Abstract: Optimum temperature for germination and emergence of redvine seed in either petri dishes or soil was 35 C. Reductions in germination and emergence occurred at constant temperatures above or below this temperature. No germination or emergence occurred at temperatures above 40 or below 25 C. Germination in petri dishes first occurred on day 8, and emergence was first observed 12 days after planting in a soil medium. Maximum redvine seedling emergence of 74% occurred in soil when seed were planted 0.5 cm deep, with decreases in emergence noted at depths below 5 cm. No emergence occurred over the 35-day period evaluated when redvine seed were planted on the soil surface or at a depth of 10 cm in soil. Redvine germination was not affected by solution pH, whereas germination did not occur when osmotic stress of as little as -200 kPa was applied to seed. Nomenclature: Redvine, Brunnichia ovata (Walt.) Shinners #3 BRVCI. Additional index words. Temperature, planting depth, pH, moisture stress, BRVCI.

Journal ArticleDOI
TL;DR: In this paper, the authors quantify the effects of cover crops on growth and nitrogen accumulation by soybean [Glycine max (L.) Merr,] and corn (Zea mays L.) on a Nicollet loam (fine-loamy, mixed, mesic Aquic Hapludoll) near Boone, Iowa.
Abstract: Combining cover crops and conservation tillage may result in more sustainable agricultural production practices. Objectives of this on-farm study were to quantify effects of cover crops on growth and nitrogen accumulation by soybean [Glycine max (L.) Merr,] and corn (Zea mays L.) on a Nicollet loam (fine-loamy, mixed, mesic Aquic Hapludoll) near Boone, Iowa, Our farmer-cooperator planted soybean in 1988 using ridge tillage into an undisturbed strip with a hairy vetch (Vicia villosa L. Roth) cover crop and into a strip where previous crop residue and a negligible amount of cover crop had been incorporated by autumn and spring disking. In each strip, we established four plots for soil and plant measurements. Our cooperator planted corn on the same strips in 1989 into a cover crop that consisted of both hairy vetch and winter rye (Secale cereale L.). We determined the source of N accumulated by the corn by applying 67 kg N/ha of 15N depleted NH4NO3 fertilizer. In the absence of cover crops, early season soil NO3-N levels in the top 30 cm were higher, and corn growth and N accumulation were more rapid. At harvest, the corn grain, stover, and cob together accounted for 36 and 39 percent of the 15N fertilizer for the ridge tillage and disked treatments, respectively. We suggest that lower net mineralization of organic matter or greater denitrification losses before planting reduced the availability of soil N, This created an early season Nstress in corn grown with cover crops that was not overcome by broadcast fertilizer N applied three weeks after planting. Our on-farm research study has helped focus continuing efforts to determine if non-recovered fertilizer N is being immobilized in microbial biomass, lost by denitrification, or leached below the plant root zone.

Book
01 Jun 1991
TL;DR: Tropical planting and gardening, tropical gardening, this article, Tropical gardening, Tropical planting, gardening, and tropical planting, agriculture, and soil fertility, etc., is a topic of interest.
Abstract: Tropical planting and gardening , Tropical planting and gardening , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی

Book ChapterDOI
TL;DR: In this paper, the effect of sowing date, nitrogen, water, soil compaction and temperature on the growth and distribution of winter wheat roots under UK field conditions has been measured.
Abstract: Winter wheat has one of the most prolific root systems of all arable crops. A crop with a total dry matter production of 20 t/ha will have 1.5 t/ha of roots with a total length approaching 300,000 km/ha. The effect of sowing date, nitrogen, water, soil compaction and temperature on the growth and distribution of winter wheat roots under UK field conditions has been measured. Application of nitrogen fertilizer increased total root lengths by 30% and stimulated growth in all soil layers. A 100-day drought reduced root growth only in the topsoil, and increased it in the subsoil provided that nitrogen fertilizer was given. Roots of droughted crops penetrated about 20 cm deeper than those of irrigated crops. On average, two thirds of all wheat roots were in the top 20 cm of soil, and as average soil temperatures vary little with depth down to one metre under UK conditions, temperature is unlikely to be a significant factor for root distribution. Soil porosity or mechanical impedance appears to be a major determinant of root distribution.

Journal ArticleDOI
TL;DR: The effects of seed mass and emergence time on growth and reproduction of the annual, C4 grass, Panicum dichotomiflorum Michx.
Abstract: The effects of seed mass and emergence time on growth and reproduction of the annual, C4 grass, Panicum dichotomiflorum Michx., were investigated in an experimental field study. Individual seeds of P. dichotomiflorum of known mass were sown into marked plots in four newly-abandoned fields that differed in soil nutrient availability, soil moisture and the time of the year in which they were abandoned. Seedling emergence was monitored daily for four weeks following sowing. In none of these fields was there any relationship between seed mass and emergence time. Analyses of covariance indicated that the effects of seed mass and emergence date on plant performance varied among fields. Seed mass affected performance in one field (SOUTH EARLY) where abiotic stress after emergence was high. In contrast, later emergence significantly reduced performance in all four fields. We used a path analysis to decompose the direct and indirect effects of seed mass and emergence time on plant performance in each field. The path analysis revealed that in all four fields, final weight had a significant positive effect on seed production. The effect of seed mass and emergence time had variable (and often opposite effects) on these traits. Seed mass only had a significant positive, direct effect on seed production in the most abiotically stressful field (SOUTH LATE). In the other fields, the effects of seed mass on fecundity were mediated by the effect on final weight. Thus, the effects of seed mass and emergence time on growth and reproduction in P. dichotomiflorum vary across environments.

Journal ArticleDOI
TL;DR: The fertilizer efficiencies in the non-drought years were higher than generally reported in south-eastern Australia, and indicate potential for profitable delayed application of N fertilizer to wheat.
Abstract: Dryland wheat was fertilized with ammonium nitrate or liquid urea-ammonium nitrate at the time of sowing or about 3 months later (generally at the terminal-spikelet stage) on a well-drained site near Harden on the south-west slopes of New South Wales. The experiments continued from the second to the fifth year (1981-1984) of the cropping phase of a crop-pasture rotation. The maximum agronomic efficiencies for yield in the four consecutive years were 19, 4, 23 and 25 kg grain per kg of applied nitrogen (N). The three large responses were obtained in wetter than average seasons and the small response was obtained during drought. In the last three years of the study the yield response to nitrogen at the terminal-spikelet stage was found to be close to but slightly less than that for N applied at sowing. In those years the agronomic efficiencies for the late-applied N were 0, 22 and 22. The apparent recovery of fertilizer N in the above-ground parts of the crop at maturity was up to 70% of the fertilizer applied in the year of sowing, and, after the drought during which there was little uptake of fertilizer N, up to 62% by the subsequent crop. The fertilizer efficiencies in the non-drought years were higher than generally reported in south-eastern Australia, and indicate potential for profitable delayed application of N fertilizer to wheat. Grain-protein responses were variable from year to year and are discussed against a simple theoretical background of the amount of N applied and grain-yield response.

Journal ArticleDOI
TL;DR: Four field trials were done with narrow-leafed lupins in 1988 - 1989, to examine the effect of sowing seed with 5% and 0.5% cucumber mosaic virus (CMV) infection on subsequent virus spread, grain yield and percentage of infection in harvested seed.
Abstract: SUMMARY Four field trials were done with narrow-leafed lupins (Lupinus angustifolius) in 1988 - 1989, to examine the effect of sowing seed with 5% and 0.5% cucumber mosaic virus (CMV) infection on subsequent virus spread, grain yield and percentage of infection in harvested seed. A proportion of the CM V-infected seed failed to produce established plants and thus, plots sown with 5% and 0.5% infected seed contained 1.5-2.9% and 0.2-0.3% of seed-infected plants respectively. The rate of virus spread by aphids was faster and resulted in more extensive infection at maturity in plots sown with 5% infected seed than with 0.5% infected seed. In three trials, sowing 5% infected seed resulted in yield losses of 34 - 53% and CMV infection in the seed harvested of 6 - 13%. The spread of CMV infection resulting from sowing 0.5% infected seed did not significantly decrease yield. However, late CMV spread in these plots caused > 1% seed infection. In the fourth trial, which was badly affected by drought, CMV spread only slowly, there was no significant effect of CMV on grain yield and the percentage of infected seed harvested was 3–5 times less than that in the seed sown. When CMV-infected seed was sown at different depths, target depths of 8 and 11 cm decreased the incidence of seed-infected plants by c. 15% and c. 50% respectively compared with sowing at 5 cm. However, in glasshouse tests, treatment with the pre-emergence herbicide simazine failed to selectively cull out seed-infected plants. The field trials were colonised by green peach (Myzus persicae), blue-green (Acyrthosiphon kondoi) and cowpea (Aphis craccivora) aphids. When the abilities of these aphid species and of the turnip aphid (Lipaphis erysimi) in transmitting CMV from lupins to lupins were examined in glasshouse tests, short acquisition access times favoured transmission. With 5–10 min acquisition access times, overall transmission efficiencies were 10.8%, 9.4%, 6.1% and 3.9% for the green peach, cowpea, blue-green and turnip aphids respectively.

Journal ArticleDOI
TL;DR: In each experiment there was a common relationship between yield and P content in lupin tissue, regardless of how the superphosphate was applied, suggesting that lupins responded solely to P, and other factors did not alter yield.
Abstract: Summary. Five field experiments with lupins (Lupinus angustifolius) measured the effectiveness, for production, of 4 superphosphate placements either: (i) drilled with the seed to a depth of 4 or 5 cm; (ii) applied to the soil surface (topdressed) before sowing; or (iii) banded 2.5-5 cm and 7.5-8 cm below the seed while sowing. Levels of applied phosphate (P) from 0 to 36 kg P/ha were tested. In all experiments lupin grain yield responded to the highest level of superphosphate applied. At this P level, the average grain yield from all trials was 1.16 t/ha for the deepest banded treatment. This was 0.38 t/ha (49%) better than P drilled with the seed, and 0.62 t/ha (115%) better than P topdressed. Relative to superphosphate drilled with the seed and regardless of the lupin cultivar or the phosphate status of the soil, the effectiveness of superphosphate was increased by 10-90% by banding below the seed, and decreased by 3040% by topdressing. Increasing the levels of superphosphate drilled with the seed generally reduced the density of seedlings and reduced early vegetative growth, probably due to salt or P toxicity. However, during the growing season, the plants treated with high levels of superphosphate recovered, so that eventually yields of dried tops and grain responded to increasing superphosphate drilled with the seed. In each experiment there was a common relationship between yield and P content in lupin tissue, regardless of how the superphosphate was applied, suggesting that lupins responded solely to P, and other factors did not alter yield. We recommend that farmers band superphosphate -- 5-8 cm below the seed while sowing, rather than continue the present practices of either drilling the fertiliser with the seed, or topdressing it before sowing.

Journal ArticleDOI
TL;DR: Early flowering before the achievement of adequate plant size and then the setting of a large number of pods resulting in few seeds in each were identified as the main reasons for the low seed yields in chinoli.
Abstract: Experiments were carried out between 1983 and 1987 in a cool but dry environment in Tasmania to evaluate the growth, development and yield of chinoli compared with the Brassica napus cultivar, Marnoo. In 1983/84 chinoli plants became large, with many pods, but then lodged at the stage of peak pod development. Seed yields were less than half those of the B. napus lines and only slightly better than that of B. campestris, ‘Jumbuck’. In subsequent experiments, lodging was either delayed or completely eliminated, either by the application of plant growth regulators, particularly PP333, or by using low populations or late sowing. However, these remedial measures were all associated with lower seed yields. Early flowering before the achievement of adequate plant size and then the setting of a large number of pods resulting in few seeds in each were identified as the main reasons for the low seed yields in chinoli. Irrigation after anthesis increased numbers of seeds/pod and thus gave better seed yields, but still not as high as those of Marnoo.

Journal ArticleDOI
TL;DR: In this article, the development of soil salinity during germination and early seedling growth experiments were conducted in buckets filled with 20-cm deep soil, which consisted of a control and three saline treatments with initial chloride concentrations of 30, 60 and 90 meq/l.

Journal ArticleDOI
TL;DR: High Mn seed, either obtained artificially by soaking seed in MnSO4 before sowing, or naturally from the parent plant, increased grain yield of barley grown in Mn-deficient conditions, and in both -Mn and +Mn treatments, barley grown from high Mn seed had a greater grain yield than that from low Mn seed.
Abstract: Manganese (Mn) deficiency which decreases barley (Hordeurn vulgare L.) yields can be difficult to eliminate by fertilizer applications. We hypothesized that higher Mn content of barley seed could decrease the severity of Mn deficiency and thus decrease yield loss due to that deficiency. Galleon barley with different amounts of Mn in the seed (low Mn seed: 0.08-0.26 8g per seed; medium Mn seed: 0.34-0 -62 8g per seed; high Mn seed: 0-74-1.208g per seed) was grown in field, glasshouse and growth cabinet experiments. In two experiments, seeds were soaked in MnS04 and had Mn contents of approximately 50 8g per seed. High Mn seed, either obtained artificially by soaking seed in MnSO4 before sowing, or naturally from the parent plant, increased grain yield of barley grown in Mn-deficient conditions. In both -Mn and +Mn treatments, barley grown from high Mn seed had a greater grain yield than that from low Mn seed. High seed Mn increased root dry weight, Mn content of both roots and shoots, shoot dry weight, number of early tillers, plant survival and number of grains per plant, but had no effect on weight per seed. Maximum grain yield was achieved by sowing seed with a high Mn content and applying Mn fertilizer; neither treatment completely corrected Mn deficiency on its own.

Journal ArticleDOI
TL;DR: The response of several maize inbreds to soaking injury is characterized and the importance of ethanol and acetaldehyde accumulation as determinants of flooding tolerance is examined.
Abstract: Field emergence of maize (Zea mays L.) can be severely reduced by flooding shortly after planting. This study was conducted tio characterize the response of several maize inbreds to soaking injury and to examine the importance of ethanol and acetaldehyde accumulation as determinants of flooding tolerance

Journal ArticleDOI
TL;DR: In this article, a liquid coating formulation that contained a suspension of an aqueous binder (Pelgel or Polyox N-10), a finely ground solid particulate material (Agro-Lig or muck soil), and a bioprotectant, Trichoderma harzianum strain 1295-22, was developed.

Journal ArticleDOI
01 Aug 1991-Heredity
TL;DR: Experimental populations were set up in the glasshouse in order to investigate the factors responsible for the increase in B-chromosome frequency between the seed and seedling stages of Allium schoenoprasum at the River Wye.
Abstract: Experimental populations were set up in the glasshouse in order to investigate the factors responsible for the increase in B-chromosome frequency between the seed and seedling stages of Allium schoenoprasum at the River Wye, Powys, S. Wales. Both the density of sowing (100, 250, 500 and 1000 seeds per pot) and the availability of moisture (normal, waterlogged and drought) were varied in the experimental system, which involved growing plants in small plastic multipots. Sowing density had no effect on the B-chromosome constitution of survivors, but the effect of moisure on the proportion of B-containing plants amongst the survivors was significant at the 5 per cent level. Moisture also had a significant effect on the proportion of non-standard B-types amongst the survivors. Drought conditions had the most pronounced effects, and the significance of this is discussed in relation to the conditions encountered by A. schoenoprasum at the River Wye.

Book ChapterDOI
01 Jan 1991
TL;DR: The life cycle of the rice plant is generally 100 to 210 days; the mode falls between 110 and 150 days; in temperate climates, the average duration from sowing to harvest is about 130 to 150 days.
Abstract: The life cycle of the rice plant is generally 100 to 210 days; the mode falls between 110 and 150 days. In temperate climates, the average duration from sowing to harvest is about 130 to 150 days. Cultivars with growth duration of 150 to 210 days are usually photoperiod sensitive and planted in the deepwater areas. Temperature and day length are the two environmental factors affecting the development of the rice plant, which can be divided into three main phases (Vergara 1970): vegetative phase—from seed germination to panicle initiation reproductive phase—from panicle initiation to anthesis ripening phase—from anthesis to full maturity

Journal ArticleDOI
TL;DR: Yields of weedfree perennial warm-season grasses were determined in the year of planting and the year after planting, and carbofuran was considered the best recommendation for establishment of switchgrass and Caucasian bluestem under the conditions of the experiment.
Abstract: Tall growing, perennial, warm-season grasses that produce 65 to 75% of their yield in mid-summer may provide needed summer grazing; however, establishment is often slow and inconsistent when compared to cool-season grasses. Improved establishment would make these warm-season grasses less vulnerable to annual weed competition. No-till plantings of switchgrass (Panicum virgatum L.) and Caucasian bluestem (Bothriochloa caucasica (Trin.) C. E. Hubbard] were made at Blacksburg, VA (37° 11' N° 80° 25' W, 610-111 elevation) on a Groseclose loam soil (clayey, mixed, mesic Typic Hapludult). Eight experiments included carbofuran (2,IDihydro- 2,2-dimethyl-7-benzofuranol methylcarbamate) at 0 and 1.1 kg ai. ha⁻¹ and atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) at 0, 1.1, and 2.2 kg ai. ha⁻¹ in all possible combinations. Seedling growth, leaf appearance rates, seedling weights, density, leaf elongation rates, and heights were measured. Yields of weedfree perennial warm-season grasses were determined in the year of planting and the year after planting. Carbofuran at 1.1 kg ai. ha⁻¹ placed in the row with the seed at planting enabled seedlings to develop faster, elongate more rapidly, and provided more and heavier seedlings than without carbofuran. In the year after seeding, yields of warm season grass were higher where carbofuran was applied at seeding in seven of eight experiments. Atrazine reduced herbage yields as well as population, weight, development, and leaf elongation rate of seedlings in the seeding year. Atrazine at 1.1 kg a.i. ha−1 was not detrimental to either grass in the second year of the study. Atrazine at 2.2 kg a.i. ha⁻¹ appeared to injure switchgrass more than Caucasian bluestem. Yields in the year after planting further confirmed these observations. Atrazine at 1.1 kg ai. ha⁻¹ increased yields over untreated controls. However, in one of four switchgrass experiments, yields of grass treated with atrazine at 2.2 kg ai. ha⁻¹ were lower than controls the year after planting. A yield reduction was observed in two of four caucasian bluestem experiments. All stands were nearly pure with planted species the year after planting. Carbofuran and atrazine at 1.1 kg a.i. ha¹ was considered the best recommendation for establishment of switchgrass and Caucasian bluestem under the conditions of the experiment. Contribution of the Dep. of Crop and Soil Environmental Sci. Virginia Polytechnic Institute and State Univ., Blacksburg, VA 24061.

Journal ArticleDOI
TL;DR: The soil-active fungicides, fosetyl-Al and metalaxyl, increased trunk and shoot growth of Royal Gala'/M.26 in the first season after planting and peat moss or composted manure mixed into the planting hole increased growth.
Abstract: Increasing the N application rate (in the form NH 4 NO 3 ) to newly planted Marshall McIntosh'/M.9 apple (Malus domestica, Borkh.) trees beyond 76 g N per tree per year reduced growth in the first two growing seasons. Peat moss or composted manure mixed into the planting hole of Royal Gala'/M.26 increased growth in the first growing season after planting. The soil-active fungicides, fosetyl-Al and metalaxyl, increased trunk and shoot growth of Royal Gala'/M.26 in the first season after planting (...)

Journal ArticleDOI
TL;DR: A simple model was used to describe the effects of plant density and sow date on yield, and proved useful for highlighting differences among cultivars and sowing dates.
Abstract: Effects of plant density and spatial arrangement on growth and yield responses of 4 peanut cultivars were examined under fully irrigated conditions at Kingaroy, south-eastern Queensland (26¦33'S., 151¦50'E.). Cultivars represented either the Spanish or Virginia botanical type. Spanish cultivars had either very early (Chico) or early (McCubbin) maturity, while Virginia cultivars had either medium (Early Bunch) or very late (Mani Pintar) maturity. The interaction of plant density (44 000-376 000 plants/ha) with sowing date was assessed in 3 sowings in 1984-85 (S1, 1 November; S2, 5 December; S3, 15 January), with a further sowing in 1985-86 (S4, 21 November). The interaction of plant density and spatial arrangement was assessed in 1985-86. Total dry matter (TDM) and pod yields showed highly significant (P<0.01) linear and quadratic responses to increasing plant density. Cultivars differed in their response to density. McCubbin, Early Bunch and Mani Pintar showed no responses to increased density above 88 000 plants/ha, while maximum TDM and pod yields of Chico were recorded at 352 000 plants/ha. Sowing date had no significant effect on the response of any cultivar to plant density. However, all cultivars except Chico produced significantly less TDM and pod yield in S3, due to cool temperatures and/or frosts terminating growth. A 1 : 1 (square) planting arrangement produced significantly greater pod yields and more TDM than the conventional commercial practice of rows 90 cm apart. Planting in a double-row arrangement (20 cm between 2 rows) based on 90 cm centres produced intermediate pod and TDM yields. A simple model was used to describe the effects of plant density and sowing date on yield, and proved useful for highlighting differences among cultivars and sowing dates. A limitation of the model was a tendency to overestimate pod yield at low plant density in Spanish cultivars, where the harvest index declined at very low plant densities.