Optimum plant population and crop productivity
Nazer Manzoor, Shakeel Ahmad Anjum, Nadeem Akbar, Iftikhar Ali, Abdul Shakoor
Agro-biology Laboratory, Department of Agronomy, University of Agriculture, Faisalabad 38040, Pakistan
Plant population is defined as the total number of plants present at unit area of land, while plant spacing is the arrangement of plants on an area. The yield of crop is directly influenced by population of plant. Actually the yield of a crop is the end result of final plant population which is influenced by the number of viable seed germination and survival rate. The population of plant should not so much high that can drain out most of the moisture from the field before the crop reaches to maturity stage. As well as population should not too low that moisture remain unutilized.
If the concentration of plants is high then certain alterations in growth of plant can be observe. As plant height is increased, in high plant concentration due to the competition for light. The thickness of leave may reduce due to high plant population and leaf geometry is also altered due to high population pressure. High plant density cause low yield of individual plant due to reduction in number of ears in indeterminate plants. While reduced yield in determinate plants is due to small size of ear panicles.
Crop stand establishment plays a key role in crop life cycle and can lead to a well-established planting, dynamic growth and ultimately high production of the crop. The aim of establishing a good crop stand is to attain Maximum and uniform germination and emergence vigorous seedlings, these vigorous seedlings may also perform well under stress conditions. Planting time, land preparation, sowing methods and seed quality are some important factors which can affect the population of plant.
High and better crop establishment rates are keys for optimum plant population, uniform growth and maturity, crop’s resistance to diseases and insects, competing with weeds and optimizing yield. Good crop stand establishment is essential for the efficient use of water, light and available resources.
The quality of seed is the most important factor which affects plant population. Seed should always be disease free to ensure optimum plant population. High plant population enhances the interplant competition for nutrients water and light which affect the yield due to the stimulation of apical dominance and induces barrenness which ultimately decreases ear production per plant in maize.
The population of plants should always keep optimum. Optimum plant population insures maximum crop yield. Soil cover and the size of plant are the factors that influence optimum plant population. Following are the approaches that help to maintain optimum population of plants.
- Preparation of seed bed
- Arrangement of rows and beds
- Maintenance of row spacing
- Accurate planting time and methods
- Seed of good quality and health
- Insuring maximum germination percentage
Crop productivity is usually affected by limiting resources and it determined how the crop utilizes these resources. Crop productivity can be enhanced by maintaining optimum plant population in the field.
The global requirement of agricultural crops for food is increasing at a rapid pace. Global food production must be increased between 50 and 70% by 2050 to meet the projected population growth. The possible options to fulfill this food need are to increase area of production or to increase crop production per unit area. Increasing productivity on existing agricultural land is preferable as it avoids greenhouse gas emissions and the large-scale disruption of existing ecosystems associated with bringing new land into production.