Can an increase in nitrogen rate mitigate damages caused by uneven spatial distribution of maize plants at the sowing row?

Abstract

An uneven distribution of maize plants at the sowing row can decrease grain yield. This work was carried out to evaluate the effect of an increasing nitrogen rate on maize agronomic performance under different variation coefficients of plant spatial distributions at the sowing row. The experiment was conducted in Lages, Santa Catarina State, South Brazil. Three variation coefficients (VC) of plant spatial distribution (0, 50, and 100%) were tested. At the 0 level, seeds were evenly distributed 17 cm from each other. In the other treatments with uneven spatial distributions, the distances between two neighbouring seeds ranged from 2 to 54 cm. Four nitrogen side-dress rates (0, 125, 250, and 375 kg N ha-1) were evaluated. The increase in VC of plant spatial distribution decreased the leaf area and the relative chlorophyll content of the index leaf at silking, regardless of the nitrogen rate. When the variation coefficient of seed placement was enhanced from 0 to 100%, such behaviour contributed to a decrease in the number of kernels per ear and the grain yield. Therefore, increasing the amount of N was not an efficient strategy for preventing yield losses caused by irregular plant spatial distribution at the sowing row.

Growth and fruit yield of sponge gourd (Luffa acutangulaL.) as influenced by combination of plant spacing and chicken manure

“…The use of spacing that is too wide is also very inefficient, because the yield per unit area of land obtained decreases with a decrease in the number of plant populations. This is in accordance with the opinion of [11] stated that if the increase in population is still below the increase in competition, the increase in production or yield of crops will be achieved higher at denser spacings. Based on the results of research that has been carried out on farm business analysis on spacing and doses of chicken manure, it is stated that the R:C ratio obtained is more than one, which means that farming in the cultivation of gambas can be said to be profitable or feasible to do (Figure 1).…”

Nitrogen use efficiency and grain yield of corn hybrids as affected by nitrogen rates and sowing dates in subtropical environment

“…In the 2018/2019 growing season, the Brazilian average productivity of first corn crop was only 8.2 Mg ha -1 (Conab, 2020). However, experiments carried out by Kolling et al (2019) and Panison et al (2019) showed that first corn crop has a yield potential higher than 15 Mg ha -1 in this region. The generation of information that allows better understanding of management practices for high corn grain yield is fundamental to enhance the cereal-cultivated first crop area, enabling rotation with soybean in spring/summer and increasing the sustainability and resilience of grain production systems in southern Brazil.…”

Agronomic performance of mayze hybrids under application of prohexadione-calcium and nitrogen topdressing

“…The relative chlorophyll content associated with NDVI is an indication of conversion of light energy into chemical energy, i.e. into photoassimilates (Kolling et al, 2019). Thus, Table 5.…”

“…In Brazil, cultivation ranges from small properties to large commercial plantations; according to Conab (2020), national production of 100.48 million tons is estimated for the 2019/2020 harvest, with average productivity of 5.5 t ha -1 ; obtained through the set of management techniques to achieve high productive ceilings. One technique is the use of modern hybrids coupled with modifications in plant arrangement, intensification of nitrogen fertilization, and the use of products aimed at maximizing productivity (Kolling et al, 2019).…”

“…Excessive growth increase, in plant height and ear insertion height, are morphological characteristics that may indicate pre-disposition to lodging and breaking of corn plants, intensified when combined with early summer sowing in the South region of Brazil, corresponding to the end of the agro-climatic zoning period for the Campos de Lages microregion, and under high plant density, due to lower water availability, incident intensity of solar radiation during the crop cycle, increased intraspecific competition for environmental resources (water, light, and nutrients), resulting in reduced productivity and grain quality (Kolling et al, 2019).…”