Agronomy: Frequently Asked Questions
- What is the range of temperature sensitivity?
- For spring planting why do you sell a short maturity hybrid
- I planted three different hybrids at the same time, but one did not pollinate. why?
- What steps do you take to ensure your seed will germinate after it's being conditioned?
- Can anyone use a seed treatment?
- How do long and hot days impact growth?
- How do long and hotnights impact growth?
- What are other factors (other than heat) dangerous for pollination?
- What are the factors favorable for pollination?
- What are basic criteria for balancing fertilizer?
- What is thecriteria for the most suitable land for corn planting?
- What are thebest stages/timing for irrigation?
- What arethe best stages/timing for fertilizer application?
- What is the Impact ofweeds on yield?
- What is the difference between heat & drought resistance, which is more important for Pakistan?
- Can we calculate the losses due to early harvesting?
- Why you discourage planting in October and November?
- What arethe most critical stages for frost & what is the impact of frost?
- What are the best methods for corn grain storages,you can suggest to farmers?
- Which pest is most dangerous for corn?
- What is the future of corn?
Metabolic activities are affected at temperature > 100 Fo or 40 Co and < 10 Co.
Different hybrid offerings provide farmers choices to meet their needs to spread planting risks. This is to spread planting risk. Each hybrid may respond differently in the same environmental conditions. Multiple offerings avoid environmental risk. All hybrids of different maturity planted at same time will mature at same time as the heat accumulation for all hybrids is same. This will be little difference observed in maturity.
Each hybrid may respond differently under same conditions. This is due to Genetic x Environment interaction which affects hybrid performance. Even the same hybrid planted at same location planted at same location may not perform the same every year. If you have experience with a particular hybrid being sensitive in a paticular area, you may not want to plant that hybrid in the same area again.
Seed is randomly tested before dispatch from seed plant for germination. Efforts are made to ensure that all seed is quality seed that should germinate under ideal conditions and necessary steps are taken to avoid any mishap.
Improper seed treatment affects seed germination and seedling because seed is senstive to chemicals. Dealers and farmers should be educated and knowledgeable about proper seed treatment techniques and handling before use.
Continuous heat, drought or any stress affects plant growth. Long and hot periods lasting for more than 24 hours disturb plant cycles and photosynthesis (food making process) which ultimately affects yield.
Long, hot nights cause the plant to go through photorespiration that causes loss of enery and affects plant growth. The plant uses its energy to defend its system, therefore after photorespiration there is no energy left to run the plant metabolism.
- Very low (<20%) humidity
- Very high (>80%) humidity
- Moisture stress
- Nutrient stress (specially nitrogen)
- Long duration of rain and continuous wind storms
- Silk and pollen timing difference.
- Even germination
- Sufficient nutrients
- Soil water availability during pollination
- Optimum temprature: 30-38 Co
- Relative humidity: 30%-50%.
NPK 1:0.5:1 or depending on soil test
Well drained loose soils and soils where vegetables can be planted are generally good for corn.
- The soil surface should not remain dry for good corn yields
- Corn should be irrigated frequently during all stages of growth with no water stress from teaseling
- Pollination to physiological maturity (black layer)
- Before tasseling: basal application V6 , V10, V14 leaf stages
- Before planting: total Phosphorus and Potash fertilizer as basal dose
- Before silking: total Nitrogen fertilizer in four split doses
It depends on the weed pressure, generally weeds make 20% loss especially in the early 30 days when the crop is young.
When there is heat, the plant is affected by drought. Plant systems do not work effectively in heat >38 Co and It is difficult to separate both.
It will be difficult to calculate precisely, but early harvesting will cause the grain to weigh less because it is not fully developed.
Frost damage may occur before V5 stage and slow or no growth in December due to very low temperature. Therefore, a delay in planting will avoid plant from frost.
Just after germination to V5 stage. In this period leaves may die, become yellow, brown and no growth. Plant will recover before V5 stage when growing point is below soil.
- Shelled corn - dry grain at below 13% moisture
- Unshelled cobs can be stored if dry at 20% moisture
- Keep in a well aerated place
- Avoid excessive moisture and humidity.
Shoot fly, borer, shoot worm, army worm and mites, all can reduce corn yield.
There is a huge demand for corn grain in the world and Pakistan. Corn grain is used for biodiesel, food and feed worldwide and as the population increases, the need will continue to grow.