Showing papers on "Sowing published in 1977"

Nodulation studies on chickpea (Cicer arietinum)

Abstract: Glasshouse and field experiments were conducted with chickpea (Cicer arietinum) rhizobia to determine the inoculation requirements of this highly Rhizobium-specific legume. There did not appear to be any host-strain specificity within the species. There was a strong nodulation response to inoculation with four strains (unaffected by time of sowing) even at a level of inoculant application below normal. In some field experiments, nodulation responses were not reflected in improved foliage dry matter production or seed yield. However, the correlations between degree of nodulation and plant growth and seed yield were significant. There was a distinct advantage in using solid inoculant applied in the row with the seed instead of conventional seed inoculation when fungicide-treated chickpea was being sown. Two strains, CB1189 and CC1192, were considered suitable for inoculants.

Seasonal light interception and canopy development in hedgerow and bed system apple orchards

Abstract: SUMMARY Pattern of light interception, in both time and space, were measured during 1973 and 1974 in apple orchards. Several planting systems were investigated and the patterns of light interception were related to structural area (leaf area (LAI), branch area (BAI) and fruit area index (FAI)). Leaf area increased rapidly in May and June and then usually declined slowly until leaf-fall in October/November. The largest recorded light interception was just over 60% by a bed system of Cox's Orange Pippin during the beginning of September 1973. All orchards showed a seasonal hysteresis when light interception was plotted against total structural area (LAI, BAI and FAI). This hysteresis is due to changes in canopy size and solar altitude. The bed systems of planting showed the largest seasonal changes in both canopy size and hysteresis. The results are discussed in relation to planting designs in orchards.

Effect of sowing date and seed rate on crop development and grain production of winter wheat.

Abstract: In a field trial in 1973-5, winter wheat cv. Lely was sown on 3 dates at 3- to 4-wk intervals from end-Sept. at low (80-90 kg seed/ha) or high (160-180 kg seed/ha) sowing rates. Delaying the sowing date decreased grain yield. This decrease was caused by a smaller number of grains/ear and a lower grain wt. Sowing rate had a positive influence on the number of ears, but a negative effect on the number of grains/ear and the grain wt. With early sowing, sowing rate was found to have no effect on grain yield, due to mutual compensation of changes in yield components. With late sowing, a higher sowing rate increased the number of ears so much that a higher grain yield was achieved. The grain yield/ear depended on the age of the tiller. Tillers that emerged earlier produced more and heavier ears. The number of grains/ear and the grain wt. could be related to the rate of development of the ear-bearing shoot. The pattern of tillering was affected by the sowing date. With early sowing, most tillers emerged in autumn and winter, whereas the late-sown wheat tillered in spring. Also, the early-sown crop consisted largely of ears from early tillers, whereas the late-sown one had many ears from late-formed tillers. (Abstract retrieved from CAB Abstracts by CABI’s permission)

Black leg (Leptosphaeria maculans (Desm.) Ces. et de Not.) of rapeseed in Victoria: crop losses and factors which affect disease severity

Abstract: Surveys made of rapeseed crops in Victoria during 1971, 1972 and 1973 showed that black leg was widespread, but its severity depended on field location and sowing date. In crops sown on or adjacent to fields growing rapeseed in the previous year, black leg sometimes caused crop failure. In fields sown before August, the disease caused major yield losses, whereas in those sown later it caused only minor losses. There were no apparent differences in severity of infection between cultivars or districts. Infections which resulted in serious stem cankers were shown to occur before flowering.

Sunflower Yield and Water Use as Influenced by Planting Date, Population, and Row Spacing1

Abstract: Sunflower (annuus L.) has only recently been grown commercially as an oilseed crop in the drier regions of the Northern Great Plains. This study was conducted to acquire preliminary information on seed yield, oil concentration, and water use for oil-type sunflower as affected by planting date, plant population, and row spacing; and to obtain an indication how these results were affected by yearly variation in precipitation and air temperature. Sunflower was grown at Mandan, N. Dak. at plant population of 25,000, 50,000, 75,000, and 100,000 plants/ha in 30- and 90-cm rows on Temvik silt loam (Typic haploboroll). Soil water withdrawal by sunflower was generally confined to the upper 150- soil depth. Water use by sunflower was consistently greatest for earlier plantings, and was not affected by population or row spacing. Significant positive correlations were obtained between seed yield and water use after 50% flowering. Water use before flowering was much greater in a year of high precipitation during this period than in a year when pre-flowering precipitation was lower. Seed and oil yield were usually highest for lowest populations and for 30-cm row spacing. Correlation coefficients showed that 80% of the total variation in oil concentration was accounted for by variation in water use and temperature. Oil concentration was more strongly influenced by water use than by temperature. Although late planting in 1973 increased seed yield for some of the higher plant populations, flowering was delayed until early September, increasing the frost hazard. Days from planting to flowering (50%) decreased as planting date was delayed.

Cultivation systems for spring barley with special reference to direct drilling (1971–1974)

Abstract: Five cultivation systems for spring-sown barley were tested on a clay to sandy-clay loam for 4 years and their cumulative effects on soil and crop measured. Four primary cultivations in the autumn, shallow (7·5 cm), medium (15 cm) and deep (23 cm) tine cultivation and mouldboard ploughing (23 cm deep) followed in spring by secondary cultivations and sowing, were compared with direct drilling seed into uncultivated soil after controlling weeds with herbicides. At the same rates of seed and fertilizer for all systems, direct drilling and shallow cultivation yielded significantly less grain than deeper tillage in the second year only; over 4 years the differences in mean yield were small and non-significant. In terms of crop output per unit of implement net energy (estimated) direct drilling was eight times more efficient than ploughing.Direct drilling and shallow cultivation caused concentration gradients of ‘available’ phosphorus and potassium to form in the top soil. Soil strength and to a lesser extent bulk density were greater without than with cultivation but these changes had only a relatively small effect on root distribution in the profile. In untilled soil the proportion of the root system was less in the surface 2·5–12·5 cm and greater in the 12·5–32·5 cm horizon than in shallow or deep tilled soil.Mean nitrogen uptake by the crop in the third and fourth seasons was least in direct - drilled barley probably due to lower rates of mineralization of soil nitrogen in compacted than tilled soil. It was deduced that for spring barley the ‘yield plateau’ was the same for each system but that optimal rates of nitrogen would be higher for crops in untilled than tilled soils.

Effect of sowing depth on plant establishment, tillering capacity and other agronomic characters of cereals

Abstract: In field trials conducted over 8 years the effect of sowing depth on plant establishment, tillering capacity, plant height, grain yield, top growth weight and patterns of root development of wheat and barley was studied. Establishment, number of grainbearing tillers per established plant, plant height at maturity and grain yield and top growth weight per plot as well as per plant were reduced with increase in sowing depth from 2 to 20 cm. Seedling emergence started earlier from large seeds and from shallow sowing. Establishment from large seeds of two varieties was better, especially for deep sowing and in clay soils. Several patterns of root and tiller development were observed at various sowing depths. Varietal differences in stand establishment under field conditions were not related to plant height. It was concluded that deep sowing beyond around 10 cm should be avoided because stand and plant vigour are adversely affected.

Inheritance of tuber initiation in tuber bearingSolanum as influenced by photoperiod

Abstract: Eight potato clones (three day-neutral (DN) Tuberosum, one dayneutral and four short-day (SD) Andigena) were used as parents. Eight genetic sets bearing P1, P2, P1⊗, P2⊗, F1, F2, BC1, and BC2 generations were developed. Two sets were DN×DN crosses, four SD×DN, and two SD×SD. Tuber initiation (TI) was evaluated in growth chambers with daylengths of 11, 13, and 15 hours. The stolons of each genotype were examined every eight days between the 38th and 86th day after planting. F1 generation means from SD×DN crosses showed complete dominance of SD reaction (late TI) over DN reaction (early TI). F1 generation means from DN × DN and SD× SD crosses showed either no dominance or a slight tendency towards the late TI parent. Within plot variances of the selfed generations suggested a variable degree of parental heterozygosity for the loci controlling TI. Andigena clones showed the greatest heterozygosity. Bell shaped frequency distributions in the segregating generations indicated that TI was under the control of several genes. It appears also that major and minor genes were involved. Broad sense heritability estimates of about 90% at 11 hours and 55% at 15 hours of daylength were computed.

The development of a hydraulic seeding technique for unstable sand slopes i. effects of fertilizers, mulches and stabilizers

Abstract: SUMMARY Hydraulic seeding is used to establish vegetation on steep slopes, but the technique is not reliable. This paper examines the effects of individual components of the technique on the germination and establishment of grasses and legumes on the sand waste left after china clay extraction. The inclusion of fast release compound fertiliser in the hydro-seeding mixture at rates above 125 kg ha- 1 seriously inhibited germination and establishment, especially of legumes. Nitrogen and phosphorus salts had the most inhibiting effect. The effect was reduced by the application of a mulch, which improved moisture levels around the surface-lying seed and increased germination, especially under dry conditions. Seedling establishment was greater on coarse than on fine sand. A peat mulch (0.8 t ha- ') increased establishment nore than did the application of most chemical stabilizers. Certain stabilizers actually inhibited germination, increased sand erosion and reduced the benefits of mulching. Seedling establishment was best on north-facing slopes. The time of sowing, and the prevailing weather conditions, determined the total establishment and determined which species became established. It was concluded that the normal practice should be modified, but that the technique should be flexible to suit the conditions prevalent at sowing. An outline of the components required and the rates of application for the effective hydraulic seeding of sand waste is given.

The effect of sample date and plant density on the carbohydrate content of forage maize and the changes that occur on ensiling

Abstract: The (early maturing) maize hybrid, Anjou 210, was sown on 1 May (1975) and 50000 (LD) and 150000 (HD) plants/ha established. Leaf, stem, ear and husk components of the shoots, and whole shoots were separately examined for changes in dry weight, soluble sugars, starch, hemicellulose and cellulose at regular intervals from 104 to 154 days after planting together with whole shoots after ensiling.Throughout the sampling period whole shoot and ear dry weights increased steadily whereas those of leaf and stem decreased in plants from both treatments.Total soluble sugar contents for plants grown at LD were at a maximum 104 days after planting compared with 125 days after planting for the HD crop. Immediately prior to ensiling whole shoot soluble sugar content was 74 and 93 g/kg D.M. for LD and HD treatments respectively.Small amounts of starch (g/kg D.M.) were found in stems (10–25), husks (40–80) and leaves (17–35) of plants grown at both densities. The starch content of the ear increased from 57 to 390 g/kg D.M. and 168 to 376 g/kg D.M. in plants grown at LD and HD respectively.For plants from both treatments hemicellulose contents of husks, leaves and whole shoots increased with age whereas those of stems decreased. Cellulose contents did not vary greatly over the growing season.On ensiling plants from both densities, total soluble sugars had virtually disappeared after only 3 days. Apparent losses (approximately 0·3 g/g), over a longer period of time, were observed in hemicellulose sugars and starch. Apparent increases were observed in cellulose contents of approximately 0·15 g/g.

Effects of Sowing Time and Sowing Density on the Growth of Subterranean Clover at Adelaide

Abstract: Growth curves have been constructed for undefoliated swards of subterranean clover (cv. Woogenellup) established at three plant densities (1,2 and 4 x l03 plants per m2) at three times of the year (May, June and August). The swards grew without any apparent water stress, until early December. The time course of shoot dry matter increase is examined by the use of a logistic function and by the recognition of three growth stages. Maximum crop growth rates ranged from 10 to 15 gm-2 day-1. The rate decreased with increase in density but increased with lateness of sowing, so that the highest crop growth rate was obtained with the lowest plant density sown in August. Estimated end-of-season yields were independent of density but decreased from about 1500 g m-2 for May sowing to 1000 g m-2 for August sowing. Effects of sowing density on the growth pattern persisted throughout the whole season. Swards took 70–100 days to attain a leaf area index (LAI) of 3, after which crop growth rates were almost constant with time and independent of short-term fluctuations in the level of daily solar radiation and average daily temperature. Swards reached a maximum LAI of about 6, LAI being linearly related to the amount of shoot dry matter up to about 600 gm-2 independent of density and sowing time. No evidence was found of an optimal relationship between crop growth rate and LAI. It is concluded that end-of-season yield is independent of plant density above 1000 established plants per m2, and that swards established as late as August have the capacity to attain a yield of 10 tonnes ha-1 provided the growing season is extended.

Yield components and cultivar, sowing date and density in field beans (Viciafaba)

Abstract: SUMMARY Delay in sowing the cultivars Ostlers (Viciafaba var. equina) and Herz Freya (V.faba var. minor) beyond late February depressed yield. Densities of at least sixty plants per m2 were required to ensure that yield was not limited by sowing rate. Differences in yield in response to changes in density were reflected particularly in changes in numbers of pod-bearing nodes per plant, but also to a lesser extent in numbers of pods per pod-bearing node. The inherently larger seed weight of cv. Ostlers compared with cv. Herz Freya did not confer any yield advantage, differences in number of beans per pod and number of pods per pod-bearing node tending to equalize the yield of the two cultivars. The most stable component of yield throughout was number of beans per pod, and the least stable was number of pod-bearing nodes per plant.

Some factors affecting the establishment of four native grasses

Abstract: The effects of fertilizer application, types of mulching and times of sowing on the field germination of seed of four native grasses (Themeda australis, Bothriochloa macra, Danthonia spp., and Stipa bigeniculata) are reported. Growth of these species in controlled environments was compared with that of Lolium perenne (ryegrass) at three temperature regimes and two levels of nutrition. Application of an NPK fertilizer had no effect on emergence or survival of the native grasses in the field. Mulching with paper or straw increased emergence of all four species and mulching with bitumen increased emergence from Themeda, Bothriochloa and Danthonia seed only, but decreased survival of the two latter species. In both field and controlled environments, germination and seedling growth of Themeda and Bothriochloa were best when maximum daily temperatures were greater than 30¦, whereas Danthonia and Stipa germinated and grew most satisfactorily when maximum daily temperatures were about 25¦. Growth of Stipa seedlings in a controlled environment was enhanced by a high level of nutrition but growth of the other species was not. Sowing seed in late spring and using a straw mulch should ensure satisfactory levels of establishment of native grass seedlings in the field in south-eastern Australia. Fertilizer application should not be necessary

Growth and grain yield of Lupinus albus at different plant populations

Abstract: The development of the early flowering cultivar ‘Ultra’ of Lupinus albus was studied in a spring sowing of six plant populations. Higher populations produced greater dry matter yields of leaf, pod, and seed. Leaf area index (LAI) increased with higher populations, but peak LAIs were low. Header seed yields ranged from 2000 kg/ha at 16 plants/m2 to 3150 kg/ha at 35 plants/m2, plant population being the most important yield component. Mainstem seed yield was constant for all populations, but branches showed reduced seed yield at higher populations. Pods per plant and seeds per pod from branches declined with increased plant density. However, even at low populations, seeds per pod on branches were fewer. Seed size and nitrogen content were little affected by changes in plant population.

Response of soybeans to planting date in south-eastern Queensland. III.* Agronomic and physiological response of cultivars to planting arrangements

Abstract: Abstvact Results from five field experiments, designed to evaluate the response of several soybean cultivars to planting arrangement, and conducted at two locations in south-eastern Queensland during 19671972, are reported. Response to planting arrangement varied depending on cultivar maturity type, planting date, and availability of moisture during growth. Averaged over cultivars and planting arrangements, seed yields for irrigated soybeans were highest for December plantings, and declined as planting was delayed. A cultivar x planting date interaction was apparent. For December planting dates, yields of all cultivars were generally highest in 50.8 cm rows. A cultivar x plant population interaction occurred, with yields of the later-maturing cultivars maximized at lower plant population levels than for the earlier cultivars. When the planting date was delayed beyond December, yields of all cultivars were maximized in narrow row-high density treatments. Yields of the narrow row-high density late plantings were equivalent to, and in the case of the late-maturing cultivars, greater than, the highest December yields. Wide row widths (101 .6 cm) were consistently lower-yielding, regardless of cultivar and planting date. Seed yields were reduced substantially by periods of severe moisture stress during growth. The relative performance of cultivars of differing phenology depended primarily on the coincidence of periods of severe stress with critical stages of development, viz. pod and seed development. In the environments involving periods of severe moisture stress, seed yields were maximized in row widths narrower than 50.8 cm, and at the lowest plant populations used (c. 95,000 plants per ha). Such treatments most closely approached low density-equidistant spacings in these studies.

Variation in the pre-anthesis development of spring rape (Brassica napus L.)

Abstract: Fifteen cultivars of spring rape (Brassica napus L.) were each sown at four different times between April and October at Perth in either natural photoperiods or continuous light. Under natural photoperiods, flowering of the Japanese cultivars Chisaya and Isuzu was delayed in later sowings, but the flowering times of all other cultivars were advanced with each successive delay in sowing. When plants were grown under continuous light another two groups of cultivars could be recognized. One group comprised early-flowering Canadian cultivars which flowered later in the June sowing than in the other sowings. The other group comprised late-flowering European cultivars characterized by a slight delay in flowering in the last sowing. The direct effects of temperature on growth rate were more important than inductive responses in determining time of flowering in all cultivars except Chisaya and Isuzu, which had substantial vernalization requirements. Other cultivars such as Komet, Bronowski, Masoweicki and Norin 16 had low vernalization requirements which were largely masked by the increase in the rate of growth with higher temperatures in later sowings. In controlled environments, considerable variation in response to vernalization, temperature and photoperiod was detected between six spring rape cultivars. The early-flowering Canadian cultivars Target and Oro were the least responsive to vernalization and under continuous light did not respond at all. European and Japanese cultivars used here responded more markedly to vernalization, and their responses were greatly influenced by temperatures experienced after the completion of vernalization. Under continuous light and high temperature, the Japanese cultivars responded markedly to 4 weeks' vernalization which apparently saturated the system. The European cultivars Bronowski and Masoweicki, on the other hand, only responded moderately.

Analysis of the Growth and Yield of Overwintered Onions

Abstract: SummaryThe growth of a number of onion cultivars sown on different dates during late summer in several years was assessed by regular sampling. The growth during the winter of five different winter-hardy cultivars was very similar, whereas that of Rijnsburger Bola, a cultivar normally sown in spring, was clearly slower. Sowing date was shown to affect final yield through its effect on overwintering size, which in turn influenced bulb size at harvest, the proportion of plants which bolted and the extent of winter losses. During the winter months the rate of leaf initiation appeared to be decreased to a lesser extent than the growth in dry weight, which itself was decreased less than growth in leaf area. The growth of the winter-hardy cultivars from all sowing dates and seasons was well summarized by a single linear relationship between the logarithm of plant dry weight and the accumulated day-degrees between 6° and 20°C from the day of seedling emergence. Using this relationship together with temperature re...

Effect of planting date on soybeans in the Namoi Valley, New South Wales

Abstract: The effect of planting date on phasic development, LAI, yield, yield determinants and seed quality of soybeans was studied in eight seasons. For all development phases up to the end of flowering, each phase was longer for longer daylengths within a cultivar, with later maturing cultivars having increasing sensitivity to daylength. LAI at flowering for each treatment was a function of time from flowering. The yield of Bragg and indeterminate cultivars (Wayne, Delmar and Ruse) decreased if planted in early November. There was generally a decreased yield at a late January planting due to small plant size (low LAI and few mainstem nodes) and in some instances, decreased seed size. Planting dates in December appeared to be optimum, although season and cultivar differences occurred. Seed oil content decreased and protein content increased as planting was delayed.

Effects of date of planting on growth and yield of contrasting potato varieties in Pembrokeshire

Abstract: Four experiments over 2 years which examined the effects of date of planting (from mid-March to early May) on the growth and yield of early, second early and maincrop potato varieties are described. In two experiments the seed used was physiologically old (heavily sprouted) and in the other two experiments relatively young seed (limited sprout development) was used. In the early variety, Home Guard, tuber yield at maturity was unaffected by delay in planting when physiologically old seed was used but increased leaf area and higher tuber yields resulted from later planting of younger seed. With both types of seed the maincrop varieties, Desiree and Maria Piper, produced larger leaf areas from later planting in one year but smaller leaf areas in the other year. In both years with both types of seed, tuber yields at the end of August were higher from the earlier plantings of these varieties. The physiologically young seed of Red Craig's Royal behaved in a similar manner to the maincrop varieties and the physiologically old seed behaved in a similar way to Home Guard.Any yield advantages of early varieties over maincrop varieties from any date of planting were small and short-lived and the physiological reasons for differences between varieties are discussed in the light of these results. It is suggested that the current classification of varieties is unjustified and that variety testing should take more account of the effects of physiological age.Tuber yields from the maincrop varieties were very high (60·80 t/ha) and this is attributed to the synchrony of leaf growth and increasing light receipts which may be readily achieved in the mild springs of W. Wales.

Control of silver scurf (Helminthosporium solani) disease of potato with benomyl and thiabendazole.

Abstract: SUMMARY Benomyl and thiabendazole, applied as dusts to seed potatoes before chitting (sprouting), reduced the incidence of silver scurf disease on the progeny at lifting and during subsequent storage. Treatment of seed tubers 4 months prior to planting almost completely suppressed sporulation during storage, even under conditions very favourable for the growth of the fungus. The fungicides appeared not to act systemically because developing tubers grown from treated seed were just as susceptible to infection after inoculation as those from untreated. Control was due to effective inhibition of sporulation on the surface of diseased seed tubers after planting. There was no reduction in the amount of disease in subsequent generations of potato crops without further fungicidal treatment. Seed virtually free from silver scurf, produced from seed treated with fungicide in the previous year, yielded progeny with as much disease as progeny from untreated seed stocks.

Effects of Seedbed Density and Nursery Fertilization on Survival and Growth of White Spruce

Abstract: The effects of seedbed densities and fertilizer levels on growth in the nursery and on performance after planting of 3-0 white spruce (Picea glauca (Moench) Voss) were studied in an experiment star...

Soil temperature and its association with maize yield variations in the Highlands of Kenya

Abstract: In the Highlands of Kenya every 1-week delay in planting maize after the onset of the rains reduces the grain yield by approximately 0·6 t/ha. No satisfactory explanation has been found for this phenomenon. A physiological growth study was made on four dates of planting per year over 4 years. Early growth rates and maximum crop growth rates showed a progressive decline with delay in planting which resulted in smaller plants at 5 weeks post-emergence and at 50 % tassel emergence in maize planted later. There was a strong relationship between the size of plant at tasselling and the final grain yield and a highly significant relationship (r = 0·94) between the size of plant at 5 weeks post emergence and the final grain yield. Other environmental studies showed that soil temperature at 7·5 cm, coupled with a soil moisture stress factor, largely controlled the dry-matter production rate during early growth, and consideration of the mean value of these two variables over the first 5 weeks of growth accounted for 70% of the variation of dry matter at 5 weeks post-emergence. It was further shown that 82% of the variation in final grain yield caused by date of planting could be accounted for by consideration of the mean value of these two variables during the first 5 weeks of growth.

Effects of Pre-Sowing Treatments of Seeds on the Germination and Establishment of Parsnips

Abstract: SummarySowing parsnip seeds ‘primed’ in salts (KNO3+K3PO4Hc2O) or polyethylene glycol solutions gave, on average, 1.8 days earlier seedling emergence than from untreated seeds. Sowing seeds subjected to different numbers and lengths of cycles of wetting and drying (‘hardening’) advanced seedling emergence by a similar amount. However, the earlier emergence from these seed treatments was small compared with that obtained by fluid-sowing pre-germinated seeds which advanced emergence by c. 4-0 days. Sowing pre-germinated seeds also increased the final percentage emergence by c. 60% compared with untreated, hardened and primed seeds, and at an early sowing reduced the spread of emergence.

The effect of soil type and related factors on sugar beet yield

Abstract: Yields of sugar and responses to fertilizers were determined in about 400 fertilizer experiments on farms throughout the sugar-beet growing areas of Britain during 14 years from 1957 to 1970. The soil at each experimental site was described and classified and the records of the experiments have been examined to determine which properties of the soil influence sugar yield. The effect of year, rainfall, elevation, region and other factors such as sowing and harvesting date were also investigated.Year-to-year variation accounted for 20 % of all variation in yield; increasing amounts of rainfall during the growing season appeared to decrease yield. There was a significant long-term trend of increasing sugar yield from the experiments of 0·042 t/ha/year. The experimental yields closely followed national yields each year but were always greater. Delay in sowing and early harvesting depressed yield by 0–02 and 0·01 t sugar/ ha/day respectively. Yields in Scotland (average 5·23 t/ha) were approximately 1·4 t/ha less than in England and Wales, but there were no evident regional differences within England and Wales.Soil regarded as moderately drained yielded better than either well-drained or imperfectly drained soil, which in turn yielded better than droughty and poorly drained soil. The difference in the adjusted yield between drainage classes was 1·0 t/ha. Surprisingly, topsoil texture had no consistent effect on mean yield (as distinct from response to fertilizer). Subsoil texture, however, had an appreciable effect, the crop on sandy subsoil and chalk or limestone yielding poorly whilst that on silt or peat yielded best. The range of differences in sugar yield due to subsoil texture was almost 2 t/ha.Yields were also examined in relation to soil profile type. Broad division into major soil groups gave meaningful differences but fine division by soil series was only useful for the 11 series on which at least ten experiments had been made. The crop yielded most sugar on gleyed calcareous soils, peats and humic gleys, and least on rendzinas and brown calcareous soils. Responses to nitrogen and potassium but not to phosphorus were affected by both topsoil and subsoil texture. Nitrogen and potassium both increased yield most on sandy soils and least on fine silts and peats.The morphology, chemical and physical condition of soil clearly affect sugar yield greatly and further research is needed in experiments planned specifically to measure their influence and provide more precise guidance for selecting the best land for the crop.

Agronomic studies on Lupinus angustifolius in Western Australia: effect of cultivar, time of sowing and plant density on seed yield

Abstract: The results of 28 experiments with sweet lupins (Lupinus angustifolius) over five seasons, in the temperate agricultural area of Western Australia south of the 29¦ latitude, indicate that the correct time of planting and variety is influenced by length of the growing season. Broadly, in the agricultural area north of Perth the early flowering cv. Unicrop sown in May gave 50 per cent higher seed yield than either Uniharvest lupin or later sowing. In the cooler area south of Perth, the effect of later sowing on seed yield was as marked, but only when it was delayed until July, when reproductive development was severely restricted. Due to the lower temperatures in the southern area there was little difference in yield between Unicrop and Uniharvest. Although there was a marked influence of plant density on seed yield, the results were inconclusive because of the failure in the majority of experiments to achieve densities at which the yield peaked and then declined. Where this was achieved there was great variation in the level of density required for maximum seed yield because of site and seasonal differences. Three experiments suggested that greater plant density will help compensate for a loss in seed yield per plant with later sowing.

Effects of rates and methods of nitrogen application on grain yields and yield components of spring-sown wheats in South Otago, New Zealand

Abstract: Results are presented from trials in which 0, 25, 50, or 100 kg N/ha was either broadcast before sowing, drilled with the seed, or topdressed after emergence. The form of N was either calcium ammonium nitrate or ammonium sulphate and urea. Grain yield responses were inversely related to yields without N and were predominantly linear for increasing rates of N. An equation describing these effects is presented. Drilling of urea with the seed at 100 kg N/ha caused severe germination injury. N as nitrolime increased grain yields mainly through increases in ear numbers. Kernel weights were slightly reduced by N and numbers of kernels per ear slightly increased in one year out of two.

Growth and N-uptake by wheat as affected by sowing date and nitrogen in irrigated semi-arid conditions

Abstract: Field experiments were made under irrigated semi-arid conditions to determine the effects of sowing date and nitrogen application on the growth and yield of wheat and nitrogen-uptake by wheat plants. Early sowing was found to be favourable to high grain production because the post-anthesis period coincided with relatively lower temperatures. Late sowing was unfavourable to grain yields since the period between anthesis and leaf senescence was curtailed by the onset of relatively higher temperature. The benefits from nitrogen were greater with early sowing because of higher nitrogen-uptake during early vegetative growth as a consequence of which, nitrogen was readily available to the plants. This resulted in better leaf expansion, and higher leaf-area indices and leaf-area duration. With late sowing nitrogen-uptake was much lower during early vegetative growth and this resulted in decreased leaf expansion, reduced leaf-area indices and leaf-area duration and therefore diminished response in grain yield to nitrogen application.

Effects of seed deterioration and seed‐bed environment on emergence and yield of spring‐sown barley

Abstract: SUMMARY Seedling emergence from barley seeds, deteriorated by storage at supra-optimal moisture contents and temperatures, was adversely affected by sowing early in spring when soil temperatures were low, and by sowing into wet seed beds. There were significant interactions between seed lots of varying levels of deterioration and seed bed condition, because the more severely deteriorated lots emerged proportionately less well than the control, non-deteriorated lots. The yield results also showed significant interactions between seed lots and seed-bed condition because plants from deteriorated seeds in low populations resulting from partial emergence failure were unable to compensate and produce plot yields similar to those of higher populations.