Sowing

About: Sowing is a research topic. Over the lifetime, 33888 publications have been published within this topic receiving 273438 citations. The topic is also known as: seeding.

Relationship between Laboratory Seed Quality Tests and Field Emergence of Common Bean Seed

Abstract: In cool climates, early planting of bean (Phaseolis vulgaris L) is recommended to assure a longer vegetative growth period Early planting exposes seed to unfavorable conditions and the commonly used standard germination test cannot predict field emergence The objective of this work was to examine the relationships between various seed quality tests and field emergence of common bean seeds Thirty-nine strains and cultivars of bean were tested in the field and laboratory over 3 yr Each year seed samples were tested in the laboratory and then planted in the field at very early, early, and at optimal planting dates The viability of seeds was test by tetrazolium staining and was generally high; standard germination was above 80%, but germination in the cool test (at 10°C) varied from 0 to 99% The percentage of seeds with broken coats varied from 05 to 503 and conductivity ranged from 7 to 45 μS cm -1 g -1 Field emergence varied from 0 to 100% Soil temperature at sowing appeared to be not only the most important environmental factor influencing field emergence but also a factor able to be used to differentiate the field emergence potential of a seed lot Only the conductivity test could be used to predict seedling emergence in the field irrespective of soil temperature at sowing At temperatures ranging from 9 to 15°C, the first and the last count of the standard germination test and the broken seed coat test should be used in conjunction with the conductivity test to estimate field emergence potential

Effect of fertilizer levels and plant densities on yield and protein contents of autumn planted maize

Abstract: -1 and 0 kg Zn ha -1 and crop was sown at plant density of 57100 plants ha -1 . Increasing fertilizer levels and plant densities linearly increased plant height and grain yield. Application of Zinc accelerated tasseling and silking of maize crop, however the application of nitrogen had no significant effect on tasseling and silking. The fertilizer levels and plant densities also significantly affected protein contents of maize grain. Application of nitrogen at higher levels improved protein contents of grain however, opposite was true for protein contents of grains collected from the crop sown under higher plant densities. It was concluded that application of fertilizer at 250 kg N ha -1 and 15 kg Zn ha -1 and the sowing of crop at plant density of 99900 plants ha -1 showed

Survey of farm management practices of the northern wheat belt of New South Wales

Abstract: A survey of management practices on wheat farms in northern New South Wales was carried out on 50 farms between 1983 and 1985 and was supplemented by a questionnaire mailed to 750 growers in 1985. Information was collected on crop rotation, tillage practice, fertiliser use and weed control practices. Data were collected from 1 paddock on each farm and included: wheat grain yield and quality, available soil water and nutrients at sowing, wild oat density, and incidence of soil-borne diseases. The 3-year average grain yield in survey paddocks was 2.2 t/ha. Multiple regression analysis was used to identify factors affecting grain yield and protein in 1985. Of the variation in wheat grain yield, 74% was explained by variation in available soil water at sowing, available soil nitrate at sowing, sowing date and wild oat density. Grain protein content declined with increasing available soil water and phosphate at sowing and with earlier sowing, but increased with available nitrate at sowing. Agronomic practices aimed at maximising wheat grain yield, in the presence of a deficiency ofavailable soil nitrate, are likely to result in a reduction of grain protein content. Likewise, responses to application of nitrogenous fertiliser are likely to be inversely related to available soil water at sowing. The mean gross margin for 1984 and 1985, based on $100/t of wheat grain, was $128. The mean gross margin for the least profitable 20% of paddocks was $37, and $253 for the top 20%. New varieties of wheat and herbicides were readily adopted by farmers. On the other hand, adoption of nitrogenous fertiliser use was slow, considering the widespread and long-standing deficiencies of nitrogen in cropping soils of the region. Crop rotation and tillage practices have changed only marginally since the late 1940s. The results of this survey indicate that the usefulness of soil testing for predicting fertiliser requirements could be improved by taking into account levels of available soil water, weed competition and sowing date and by using multiple regression analysis.

Nitrogen fixation and soil nitrate interactions in field-grown chickpea (Cicer arietinum) and fababean (Vicia faba)

Abstract: Soil in which nodulated legumes are growing often contains more nitrate nitrogen (N) than soil in which unnodulated legumes or non-legumes are growing. There is conjecture, however, as to whether the extra or ‘spared’ N is due to reduced use of soil N by the legume or to net mineralisation of legume root and nodular N. We report results of a field experiment to quantify and compare, at different levels of soil-N supply, N2 fixation, and soil-N use by chickpea (Cicer arietinum) and fababean (Vicia faba). Wheat (Triticum aestivum) was included as a non-N2-fixing control. Plants of the 3 species were grown on a low-nitrate Vertosol with fertiliser N rates of 0, 50, and 100 kg/ha (0N, 50N, and 100N), applied 6 weeks before sowing. Samples were collected at sowing and at 64, 100, 135, and 162 days after sowing (DAS) for analysis of soil nitrate, root, and grain dry matter (DM) and N and shoot DM, N, and 15N. The latter was used to estimate the percentage (%Ndfa) and total N fixed by the 2 legumes. Soil nitrate levels to a depth of 1.8 m at sowing were 11–17 kg N/ha (0N), 41–55 kg N/ha (50N), and 71–86 kg N/ha (100N). Grain yields of the 2 legumes were unaffected by soil-N supply (fertiliser N treatment), being 2.0–2.4 t/ha for chickpea and 3.7–4.6 t/ha for fababean. Wheat grain yields varied from 1.6 t/ha (0N) to 4.8 t/ha (100N). Fababean fixed more N than chickpea. Values (total plant including roots) were 209–275 kg/ha for fababean and 146–214 kg/ha for chickpea. Corresponding %Ndfa values were 69–88% (fababean) and 64–85% (chickpea). Early in crop growth, when soil N supply was high in the 100N treatment, fababean maintained a higher dependence on N2 fixation than chickpea (Ndfa of 45% v. 12%), fixed greater amounts of N (57 v. 16 kg/ha), and used substantially less soil N (69 v. 118 kg/ha). In this situation, soil N sparing was observed, with soil nitrate levels significantly higher in the fababean plots (P < 0.05) than under chickpea or wheat. At the end of growth season, however, there were no crop effects on soil nitrate levels. Soil N balances, which combined crop N fixed as inputs and grain N as outputs, were positive for the legumes, with ranges 80–135 kg N/ha for chickpea and 79–157 kg N/ha for fababean, and negative for wheat (–20 to –66 kg N/ha). We concluded that under the starting soil nitrate levels in this experiment, levels typical of many cropping soils in the region, high-biomass fababean and chickpea crops will not spare significant amounts of soil N. In situations of higher soil nitrate and/or smaller biomass crops with less N demand, nitrate sparing may occur, particularly with fababean.