Showing papers on "Sowing published in 1975"

Rate of accumulation of dry weight in seed of soybeans and its relationship to yield

Abstract: The dry weight accumulation rate in soybean (Glycine max (L.) Merrill) seed was measured for 2 yr (1971–72), utilizing four cultivars and several planting dates within each year. Rates observed ranged from 3.38 to 8.32 mg/seed/day. There were significant differences among cultivars and planting dates. There was no significant relationship between the rate of accumulation and grain yield, seed weight or final seed number. Grain yield was closely correlated with final seed number both within each year and across both years.

Fatty acid composition of grain from winter and spring sown oats, barley and wheat

Abstract: The fatty acid composition of grain has been studied in six varieties of oats, two of wheat and two of barley, sown in pots in an unheated glasshouse in winter and in spring. Differences were found between the species in composition and in their response to sowing date. Oats showed the greatest varietal variation in both total fatty acid (TFA) content and in the proportion of its component fatty acids. The content and degree of unsaturation of the oat TFA was higher in the winter sown than in the spring sown crop. Increases in the TFA content of oats, whether arising from differences in variety or sowing date, were generally followed by an increase in the proportion of oleic acid and a decrease in the proportions of palmitic and linoleic acid in the TFA. Winter sowing, as compared with spring, led to a small, but significant, decrease in the TFA content of barley and an increase in its degree of unsaturation. There were no significant changes in the content or composition of wheat TFA as a result of differences in sowing date. Factors influencing the differences in TFA content and composition between species, varieties and sowing dates are discussed.

The effect of soaking and drying seeds before planting on the germination and growth of Triticum vulgare under normal and saline conditions

Abstract: The soaking of wheat seed (Triticum vulgare L.) in water or CaCl2 solutions followed by air-drying before planting accelerated the germination but did not affect the final percentage germination and subsequent growth of the seedlings under normal conditions. However, under conditions of 0.5% NaCl salinity the soaking and drying of the seeds before planting stimulated the germination and growth of the seedlings. In no case were the presowing treatments more effective in improving the germination and root and shoot growth under 0.5% NaCl salinity than under normal condition. Under 0.5% NaCl salinity the seedlings grown from treated seeds had more extensive and deeper root systems than the seedlings grown from untreated seeds. Presowing soaking of the seed failed to improve the germination under increasing salinity of 1.0 and 1.5% NaCl.

Field environment studies on lupins. 2. The effects of time of planting on dry matter partition and yield components of Lupinus angustifolius L

Abstract: Dry matter partition, seed yield, and yield components were examined in two lupin cultivars at eight planting times. Dry matter production and seed yield both declined with later planting primarily as a result of the foreshortened growing season which reduced the production of lateral branches and consequently the number of inflorescences per plant. For a given inflorescence, planting date appeared to have no systematic effect on pod number, although pod numbers on the main stem inflorescence varied with planting date. Mean seed weight declined slightly with later planting. Unicrop, the earlier-flowering cultivar, gave higher seed yields owing to greater development of higher order lateral branches and heavier individual seeds. Flowering began when only 17-25 % of maximum dry matter had accumulated, and subsequent dry matter partition between main stem and successive orders of lateral branches emphasized the characteristic structural development of the lupin. Seed filling occurred in the last 4-6 weeks of growth when vegetative development had nearly ceased, and was almost concurrent in both cultivars, all planting times and all lateral orders irrespective of the time of pod set.

Effects of Sowing Date on Growth, Development and Yield of Photosensitive Sorghum at Samaru, Northern Nigeria

Abstract: Performance of cv. Short Kaura, a photosensitive Nigerian sorghum, was compared at Samaru in 10 sowings in 1972. Except for a 2-week interval between the 5th and 6th sowings, all sowings were at weekly intervals from 12 May to 21 July. Total dry weight and grain yield decreased with delay in sowing after 26 May at the rate of 1700 and 360 kg/ha week, respectively. Each week's delay in sowing after 12 May shortened the total growth cycle by 5.9-6 days, with 77-78% in the vegetative phase, 7-8% in the head development phase and 14-16% in the grain-filling phase. Although the date of head initiation seemed to be determined by photoperiod, sowing date also had a small but definite effect

Studies on seed pelleting as an aid to legume seed inoculation. 4. Examination of preinoculated seed

Abstract: Samples of preinoculated legume seed were obtained from commercial outlets in southeastern Australia and compared with seed inoculated in the laboratory at currently recommended rates for the numbers of rhizobia associated with the seed and performance when grown in the field and in soil in a glasshouse. There were more than 100 times as many rhizobia on laboratory-inoculated seed as on preinoculated seed. There were no detectable rhizobia on three of the 48 samples of preinoculated seed examined, 22 other samples carried very low numbers, and all but one fell below standards derived from Australian lnoculant Research and Control Service requirements. When grown in soil containing naturally-occurring or added rhizobia, laboratory-inoculated seed was generally superior to preinoculated seed in percentage recovery of inoculant strains from nodules. The differences became greater as the size of soil populations of rhizobia increased. Where naturally-occurring rhizobia were few in number or absent nodulation was satisfactory provided that the seed carried viable rhizobia at time of sowing. The numbers of rhizobia associated with laboratory preparations of inoculated seed represented the potential standards that should be the commercial objective. The consistently lower numbers on preinoculated seed indicated that some stage (or stages) of the preinoculation process itself has a letha effect on the inoculant.

Influence of Seed Size, Planting Depth, and Companion Crop on Emergence and Vigor of Seedlings in Sweetclover'

Abstract: Seed size has been shown to have an important In­ fluence on the emergence and early growth of seedlings of several forage legumes, but only fragmentary infor­ mation on seed size effects in sweetclover (Melilotus spp.) has been published. Therefore, a 2-year study was con­ ducted in which spring and fall seedings of small, medium, and large seeds of 'Madrid' and 'N13' sweetclover (Meli­ lotus officinalis (L.) Lam.) were made at depths of 19, 38, and 57 rom. The spring seeding also included a com­ parison of a companion crop (oats) with no companion crop. Data on emergence score and plant height were collected for the spring seeding only; stand count and dry matter yield of tops and roots were measured for both spring and fall seedings. The companion crop had little effect on emergence score, but it reduced stand count and plant height, and was highly detrimental to dry matter yield. The perform­ ance of Madrid was poorer in all respects than that of N13, an experimental cultivar with relatively large seeds. As planting depth was increased, stand counts decreased, but the performance of plants that emerged from the greater depths was relatively good. The most striking results of increased seed size appeared to be improved emergence score and increased dry matter production.

Behavior of aldicarb in soil relative to control of Heterodera schachtii.

Abstract: The adsorption characteristics of two soils for aldicarb sulfoxide were similar to that described by the Freundlich equation, The adsorption constant for the Holtville clay was 3.3, and that of the Buren silt loam, 0.34. Planting beds in a field of Holtville clay and another of Buren silt loam were side-dressed at 25 kg and 50 kg/ha 10% aldicarb (Temik® 10G). Comparison of field measurements of aldicarb concentrations with previous laboratory determinations of aldicarb effects on Heterodera schachtii allowed predictions of soil zones in which hatching, infectivity, and orientation of males to females would be affected. Aldicarb in the soil water of Holtville clay sufficient to interfere with male orientation extended through most of the bed profile to a depth of 46 cm 1 week after the first irrigation. Orientation could be affected in only the top 20 cm of the bed 37 days after treatment and application of 712 mm of irrigation water. In Buren silt loam, disorientation of males was estimated to occur throughout the bed 42 days after treatment and 600 mm irrigation water. Aldicarb persisted in extensive areas of the bed at concentrations sufficient to prevent infection. In small areas of the profile, aldicarb sufficient to inhibit hatching persisted. Amounts of aldicarb in soil water samples obtained directly from beds agreed well with those from the analysis of the air dried soil samples.

Effect on the Progeny of Applying Different Day Length and Hormone Treatments to Parent Plants of Lactuca scariola

Abstract: Seedlings of the self-fertilizing species Lactuca scariola L. grown continuously in 8 h days did not flower even one year from sowing. Seedlings grown in 16 h days uatil flower buds appeared 96 days after germination were either transferred to 8 h days or treated weekly with gibberellic acid (GA3), abscisic acid (ABA) or chlormequat (CCC) and retained, together with untreated control plants, in 16 h days. Each growth regulator caused characteristic morphological changes in the treated plants. All these plants flowered and produced seeds but the seeds showed distinct differences in weight, in their time to germination and in the seedlings which they produced. Germination and seedling characters depended on the light regime during germination as well as on the chemical applied to the parent plant and the rate of application. The parental treatment also affected the shape and size of the seedlings on a given day after germination, and certain treatments of the parent plant (transfer from long to short days and treatment with CCC in long days) advanced the flowering date of the seedlings. The gibberellin level in the seeds was raised, in increasing order, by treatment of the parent plant with 100 mg/1 GA3, transfer from long to short days, 10 mg/1 GA3, and 5000 mg/l CCC. It is suggested that the effect of day length on plant performance is mediated by the level of growth regelating substances within the plant and that the behaviour of seeds can be modified by the parental environment via the accumulation of different levels of certain growth factors in the seeds. A rise of one growth substance in the parent plant can result in the accumulation of a different one in the seeds.

Agronomic studies on pigeon pea (Cajanus cajan (L.) Millsp.). 1. Field responses to sowing time

Abstract: A split-plot design was used to investigate the vegetative and reproductive responses of two earlymaturing and two late-maturing Cajanus cajan accessions to eight sowing dates. Pre-flowering to pod-ripening durations varied, depending upon interactions between climatic factors and the photoperiodic responses of the accessions. Quantitative short-day, day-neutral or nearly day-neutral, and intermediate photoperiodic forms were identified. Relationships between day length, radiation, growing degree-days, and seed yield per hectare based on individual monthly harvests and harvest index were established for a sowing density of 2990 plants ha-1. Optimum sowing times were identified as late November-mid January for dry seed production in the latematuring accessions, and not later than December for periodic green pod picking in the earlymaturing accessions.

Environments inducing changes in amount of DNA in flax

Abstract: The induced large (L) genotroph of the flax variety Stormont Cirrus has 16 per cent more DNA than the induced small (S) genotroph. Their plant weights are stable in a wide range of environments but the amounts of DNA can be reverted in both L and S towards the intermediate value by growing the plants at a lower temperature for the first 5 weeks from sowing. After three generations there is no measurable difference as observed by Feulgen photometry in the amount of DNA between L and S. The reversion can be stopped at any point by growing the plants of the next generation in warmer conditions so that any number of plants can be obtained containing any desired amount of nuclear DNA up to the inducible limits. Environments of field and greenhouse experiments alter the amounts of DNA, and one environment raised the overall DNA difference between plants to 23 per cent. The effect of the seed multiplication environment must be taken into account when comparing results from different laboratories.

Sowing sugar beet in autumn in England

Abstract: Experiments in England from 1970 to 1973 investigated the possibility of extending the growing season and increasing yields of bolting resistant sugar beet by sowing in autumn rather than in spring. September-sown plants grew rapidly in spring and achieved a complete leaf cover by mid-June by which time they had intercepted 40 % of radiation incident since mid-April compared with 28 and 9% for crops sown on 13 October and 13 April respectively. By early June autumn-sown plants were 20 fold heavier than spring sown but this advantage was progressively lost with the onset of bolting. Root growth slowed as assimilates were diverted to stem and inflorescence growth. Delaying autumn sowing from late September until mid-October delayed and reduced the frequency of bolting, probably because of a shortening of the period when plants were sufficiently large to respond to cold. Cutting down bolting inflorescences at frequent intervals improved root growth of both bolters and non-bolters. However, yields from autumn sowing never exceeded those from spring sowing, the best yield from an autumn-sown crop was 6·1 t/ha of sugar which was similar to that of the spring-sown crop. To try to prevent bolting of overwintered plants the growth regulator ethephon was applied at 10000 mg a.i./l water sufficient to wet the foliage in mid-April. Growth was severely checked and 55 % of plants died. Of the remainder 25–30% fewer than in the untreated crop bolted but yields were 26–42 % less. Less concentrated doses of ethephon did not affect bolting.

Germination Behavior of Florida Pusley Seeds. I. Effects of Storage, Light, Temperature and Planting Depths on Germination

Abstract: Freshly harvested Florida pusley (Richardia scabra L.) seeds do not germinate in continuous dark, but do germinate if exposed to more than 2 hr of light each day. Increasing periods of illumination up to 16 hr per day increases the germination percentages. Scarification increases the rate of germination in the presence of light. Scarification also causes germination of seeds stored for 8 months or longer in total darkness. The seeds fail to germinate at constant temperatures of 15 C or less and at 40 C. Almost complete germination occurs at a constant temperature of 30 C, or at alternating temperatures of 20 and 30 C. The seeds germinate equally well in the pH range of 3 to 8. Increasing depths of planting reduces percent emergence, and none of the seedlings emerge from a depth of 1.5 cm or more. Air-dried seeds can be stored either at 5 or at 25 C without losing viability, at least up to a period of 1 year after harvest. Moist storage of seeds at 5 C reduces germinability.

Apparatus and method for sowing second crop in standing crop

Abstract: Seeds of a second crop (e.g. soybeans) are sown in a standing grain crop (e.g. wheat). When the grain crop is ripe it is harvested by cutting with a combine at a level slightly above the top of the partially grown second crop. Seeding of the second crop is performed using a self-driven, preferably three-wheel vehicle carrying a grain drill box having flexible tubes which fit between the rows of grain and each of which discharges the seed into a gap between two downward-inward slanted discs which first cut a slit in the ground, then deposit the seed and finally cover the slit. The discs are supported and their depth controlled in such manner as to cause minimum interference with the grain. This invention relates to a new and improved apparatus and method for sowing a second crop in standing grain. More particularly, the invention relates to the use of a seed drill of particular configuration for use in practicing a method whereby two crops may be grown on the same acreage. A typical example of use of the present invention is as follows: At present in the Middle West portion of the United States, winter wheat is sown in the Fall (e.g. October 1) and in the Spring it begins to grow. In accordance with the present invention the seeds of a second crop such as soybeans are planted between the rows of the growing wheat about June 1, for example. At this time the wheat is partially grown and the wheat has choked out any weeds starting to grow in the field. The wheat is harvested when ripe, as for example about July 4, and at this time the beans are only partially grown. The combine used to harvest the wheat is set at a level so that the wheat is cut above the tops of the beans. By this time the beans have grown tall enough and bushy enough to shade any weeds tending to grow in the field. The beans may be harvested when ripe in about October, prior to the time of planting the winter wheat for the next season. A distinguishing feature of the present invention is the seeding of the second crop (hereinafter referred to as soybeans) into the space between the rows of the standing first crop (which may be a grain and is hereinafter referred to as wheat). The apparatus of the present invention uses double discs which slit or cut the soil between the rows of wheat, direct the seeds falling from the seed drill into the slit and then cover the slit. The vehicle on which the seed drill is mounted has small, preferably rubber tired wheels which do a minimum of damage to the wheat. Another feature of the invention is the fact that the wheat may be harvested with minimal damage to the bean plants. It is, accordingly, a principal purpose of the present invention to provide for the efficient growing of two crops on the same soil with a minimum of expense and a minimum of damage to the growing first crop. Another feature of the invention is the fact that the growing wheat protects the bean crop from weeds and hence need not be weeded while the bean plants at the time of the harvesting of the wheat are large enough to shade the adjacent ground against growth of weeds. Elimination of weeds eliminates the need to cultivate and work the ground at the time the beans are planted. Heretofore attempts have been made to seed a second crop in a standing grain crop by dropping the seeds from airplanes or by broadcasting the seed. Such systems have proven unsatisfactory because of uneven distribution of the seed and further that the seeds are not deposited in the ground to a desired depth and hence are dependent upon subsequent rains to start germination. Other features of the invention are the reduction in damage to the wheat during the bean planting and the reduction of damage to the beans during the wheat harvesting. The first crop hereinafter described is specifically wheat but it will be understood that other crops which grow early in the year may be used in performance of the method hereinafter described and particularly rye and flax. Additionally, the invention describes the use of soybeans but it will be understood that other second crops may be substituted.

Effects of sowing rate, irrigation, and nitrogen on the components of yield of spring-sown semi dwarf and standard New Zealand wheats

Abstract: ‘Karamu’, a Mexican semidwarf wheat, out yielded ‘Aotea’ and ‘Arawa’ by an average of 20% when spring sown because of better grain set per spikelet and by the formation of more spikelets per ear. Irrigation raised grain yields in all cultivars by increasing tiller survival. Sowing at twice conventional rates depressed grain yields in all cultivars by reducing grain set. Nitrogen fertilisation lowered grain yields of all cultivars by 7% in unirrigated plots by decreasing ear populations, apparently by intensifying water stress. Nitrogen applied at the same rate to irrigated plots increased ear populations and grain yields by 10%. Responses support the hypothesis that poor grain set in wheat in the field is caused by insufficient assimilate supply to the developing ear.

Association of Populations of Onychiurid Collembola with Damage to Sugar-beet Seedlings

Abstract: SUMMARY In eastern England Onychiurus armatus (Tullb.) and 0. fimetarius (L.) were found associated with damaged sugar-beet seedling roots soon after sowing in mid-March, 1973, when the mean soil temperature ranged from 3 to 11 °C; observations confirmed that 0. armatus caused similar damage to seedlings und.er laboratory conditions. In field experiments Onychiurus spp. were always more numerous in the seedling root zone than between the seedling rows, but different seed spacings had no significant effect on the extent of aggregation around individual sugar-beet seedlings in the cotyledon or early rough-leaf stages.

Apparatus for planting a plurality of individual seeds in a planting furrow

Abstract: An improved seed planter having a seed conveyor which, in combination with a means for placing seeds on the seed conveyor as they are dispensed from a seed hopper, transports the seeds from the seed hopper to a seed release point in close proximity to the desired seed planting site in the tilled soil.

Undersowing Rice ( Oryza sativa ) with Stylosanthes guyanensis . II. Delayed Sowing Time and Crop Variety

Abstract: Simultaneous undersowing of upland rice with Stylosanthes guyanensis at Khon Kaen, north-east Thailand did not affect vegetative growth of rice but reduced grain yield by 19 per cent. Grain yield was not significantly affected if stylo undersowing was delayed by 10 days. Stylo growth was reduced by one half by delayed sowing and was negatively related to dry matter yield of rice variety.

Septoria nodorum on seedlings and stubble of winter wheat

Abstract: Winter wheat samples naturally infected by S. nodorum were sown in the field, in some cases after applying seed treatments. The number of diseased seedlings was closely correlated with the percentage seed infection found by plating on agar. Observations were made on the type of symptoms produced and on seedling emergence, which was reduced by deeper sowing. Pycnidial production was abundant but rare on the tips of coleoptiles, from which source spores could spread the disease. In a cool glasshouse similar numbers of diseased seedlings were produced but symptoms were more severe than in the field. Time of sowing had a marked effect on the number of diseased seedlings and on pycnidial production in the glasshouse. Ripe pycnidia were common on stubble and persisted until May or June; Leptosphaeria perithecia were also found.

Agronomic studies on Pigeon pea (Cajanus cajan (L) Millsp.) 2. Responses to sowing density

Abstract: Vegetative and seed yield in Cajanus cajan accession UQ1 were investigated over nine sowing densities ranging from 6727 to 215,278 plants per hectare. Dry matter yield per plant declined asymptotically with increasing density, while the yield per hectare v. density relationship was described by a parabolic curve. The highest yield per hectare (22,950 kg) was produced at the 0.305 by 0.305 m spacing (107,639 plants ha-1). Maximum seed yield (2774 kg ha-1) was attained at a relatively low density at a spacing 0.914 by 0.610 m (17,940 plants ha-1). At higher densities, increased stand mortality and reduced numbers of pods per plant resulted in severe yield reductions. Reduced pod number per plant was related to significant reductions in the number of pod-producing branches and the inflorescence-bearing stem length, with little change in seed size or seeds per pod. Interactions of yield components, leaf area index, and other plant parameters are discussed. *Part I, Aust. J. Agric. Res., 26: 43 (1975).

Seed planting roller device

Abstract: An improved seed planting roller for planting seeds in individual holes in the ground, and having means for reclosing the hole over the planted seed. Also, means are shown for altering the circumference of the roller for adjustment of planted seed spacing.

Laboratory Observations on tbe Effect of Soil Compaction on Slug Damage to Winter Wheat

Abstract: SUMMARY When the aggregates of fairly dry, medium-coarse soil were broken down and firmed over the seed by moderate or heavy pressure, slug damage was reduced. Coarse soil aggregates did not break down so well, particularly under heavy pressure; many seeds remained exposed and were damaged. The seed was also protected by deep planting, with the penalty of late emergence of the seedlings.

Soil texture and planting depth influence buffelgrass emergence

Abstract: Highlight: Seedling emergence and vigor of buffelgrass (Cenchrus ciliaris L.), an introduced species with widespread adaptability for revegetation in South Texas, were regulated by soil texture and planting depth. Seedling establishment rate generally was highest from surface plantings and decreased with increasing planting depth to 24 mm. Percentage emergence was lower in clay than in clay loam or sandy clay loam. Based on total emergence and seedling vigor, optimum planting depths in clay loam, and sandy clay loam soils were 6 to 12 mm. In clay soil, the optimum depth was 6 mm. The probability of successful seedings may be increased by considering the specific planting requirements of buffelgrass based on soil characteristics rather than a generalized depth disregarding edaphic factors.

Influence of sowing dates. soil amendments. and cultivars on wheat spindle streak mosaic in winter wheat

Abstract: Wheat spindle streak mosaic was reduced by sowing wheat after mid-October, instead of in the usual period, mid- to late September, but yield losses from late sowing more than offset the gain through disease reduction. Nitrogenous fertilizers and fungicides to control the probable fungus vector did not reduce the disease significantly. Several cultivars of red winter wheat, including Halytchanka, Blueboy and Miro, showed much lower incidence of disease and milder symptoms than the commercially acceptable white cultivars Genesee, Talbot, Fredrick or Yorkstar. Resistant cultivars offer the best solution at present to this disease problem.

Nitrogen Effects on Growth, Seed Yield, and Protein of Seven Pea Cultivars1

Abstract: Nitrogen fertilization effects on vegetative growth, seed yield, and seed protein of seven pea (subsp, L.) cultivars were studied under greenhouse conditions. Nitrogen was applied as ammonium nitrate at seven equally spaced intervals at rates of 0, 50, and 100 ppm N. Nitrogen fertilization with 50 ppm N increased total seed protein of five cultivars 47 to 109% due to an increase in protein/seed and higher seed yield. Protein/seed progressively increased in all cultivars as rate of N application increased. Maximum increase in protein/seed was from 26.6 to 51.9% in a semi-dwarf (SD) winter-type pea. Seed yield decreased when plants received 100 ppm N. The number of days from planting to the first flower and number of nodes to the first flower was not influenced by N fertilization except in the SD pea. Nitrogen increased the number of days to flowering and increased the number of nodes before the first flower in the SD pea. Maturity was delayed by N application in all winter cultivars except ‘Inc 16.’ The spring-type peas — ‘Alaska,’ ‘Perfection,’ and ‘P3’ (tall, spring-type) showed no maturity differences from N application. Data from these experiments should be of practical value to plant breeders working toward improvement of protein content of peas.

An analysis of a wheat yield depression caused by high sowing rate with reference to the pattern of grain set within the ear

Abstract: Grain set in spikelcts of ears was reduced in spring-sown wheat established at high sowing rate (500 viable seeds/m2) compared with wheat planted at normal rates (250 secds/m2). the reduction being greatest in spikelets positioned near the base and near the apex of the ear. Regression analysis revealed a significant and positive relationship between final grain set and spikelet dry weight at the early boot stage. Poor grain set in wheat grown at supra-optimal seeding rates was attributed to a combination of reduced carbohydrate supply Imd water stress in the young developing ear.

Influence of temperature and daylength on phenology on sunflowers in the field

Abstract: Phenological development of a range of sunflower (Helianthus annuus) cultivars was studied for a series of planting dates at Tamworth, New South Wales. The effects of extended photoperiod on development were also examined. As constant photoperiod was increased from 15 to 21 hours, time from sowing to first anther increased by nine to twelve days. Natural photoperiod for winter and summer planting gave times similar to that for constant 18 hour photoperiod. Days from sowing to first anther decreased substantially with later planting from June to November, but increased again for a February planting. Use of a growing degree day summation with a base of 1¦C (GDD1) enabled time from sowing to first anther to be predicted with precision over a wide range of temperatures within and between years. A GDD1 summation of 1245 was found for the early cultivar, Voronezskij, and of 1380 for the mid season cultivar, Stepniak.

Anti-erosion coating of seeds

Abstract: In the disclosed method, grass seed or the like is coated with an inner "sticker" coating to which is adhered discrete particles of water-activatable adhesive. The resulting seed is resistant to movement by wind and water after sowing or planting.