Trait Characteristics

1CRM to harvest moisture:
Based on the grain moisture content at harvest, relative to other Pioneer® brand hybrids. The higher the rating, the longer the growing season required for the hybrid. It serves as a relative guide to compare the maturity difference between Pioneer® brand hybrids to the grain harvest moisture stage, stated as 24% moisture.

2CRM to silking:
Based on the Growing Degree Units (GDUs) required for a hybrid to silk (flower) relative to other Pioneer® brand hybrids. It gives an indication of whether a hybrid flowers early or late relative to its CRM to Harvest Moisture rating. Hybrids with an early flowering CRM compared with black layer CRM will generally be better adapted to cool seasons within their area of adaption.

3CRM to black layer:
Based on the GDUs required for a hybrid to reach black layer (physiological maturity) relative to other Pioneer® brand hybrids. It gives an indication of whether a hybrid reaches black layer early or late relative to its CRM to Harvest Moisture rating. Black layer refers to the stage of grain fill when the plant is physiologically mature and no further grain filling or weight increment will take place. Important: To help decide if a new hybrid fits your area’s growing season, compare its black layer rating to a hybrid that you have planted previously, or one that is successfully used in your area.

4Grain yield for maturity:
Valid only to compare hybrids of approximately the same maturity (+ or – 4 CRM).

5Adaptability to high population:
A measure of the mix of genetic factors that permit a maize plant to withstand the stresses of high population and still give good standability and a high yielding ear of fine quality grain on every plant.

6Adaptability to low population:
An indicator of a hybrid’s ability to compensate (flex) ear size for low planting rates or stand loss from poor emergence or insect attack. Fertility levels and moisture must be adequate for ‘flex’ to be effective.

7Early growth ratings:
Taken when two leaf collars are visible.

8Plant height:
9 = Tall. 1 = Short.

9Ear height:
9 = High. 1 = Low.

A measure of a hybrid’s ability to stay as a green growing plant leading up to black layer (physiological maturity). It is a measure of late season plant health which may affect plant standability and suitability for silage. A high rating indicates a wider silage “harvest window” providing a greater degree of harvest timing flexibility.

11Husk cover:
Measures the length of the husk leaves extending past the end of the cob, with a loose husk cover scoring one point lower for the same length of husk cover.

12Grain drydown:
Scores represent the rate of moisture loss after physiological maturity. Since hybrids with high scores are usually wetter early in the harvest season and then dry faster, they are not recommended for early harvest where planted as a full season hybrid.

13Grain appearance:
In the bin scored down for mould, cracks, red streak, etc.

14Grain crude protein:
Ratings indicate the relative amount of protein in the grain compared with hybrids of a similar maturity. A one score difference represents approximately 0.4% change in grain crude protein.

15Grain oil:
Ratings indicate the relative amount of oil in the grain. A one score difference represents approximately 0.5% difference in grain oil content.

16Grain starch:
Ratings indicate the relative amount of starch in the grain. A one score difference represents approximately 1.5% difference in grain starch content.

17Processing use:
AC = Hybrids suitable for alkaline products.
HT = Hybrids with hard texture, suitable for dry milling of hard textured grain such as grits.

18Kernel density:
Relative rating of absolute density of kernels determined by a pycnometer.
1 = Soft (low density).
2 to 4 = Average.
5 to 7 = Hard.
8 to 9 = Very hard.

19Kernel crown:
Indicates size of dent with a higher score indicating smoother (flintier) crown on the kernel.

20Pericarp removal:
Indicates ease of removing pericarp with a higher score indicating better pericarp removal.

21Kernel red streak:
Indicates the tendency of the kernels to red streak with a higher score indicating less tendency.

22Kernel size:
Indicates relative percentage of kernels that are smaller than medium flats. A higher score indicates greater percentage of larger kernels.

23Horny endosperm:
Score determined from visual observation of cross sectioned kernels. Score indicates that portion of the kernel with hard translucent starch suitable for dry milling into maize grits. Higher scores indicate higher percentage of hard endosperm.

24Kernel colour (yellow):
Higher score indicates a pale coloured kernel. Lower score indicates a darker colour. Scores in the 5 - 7 range indicate a more desirable yellow coloured grain.

25Northern Leaf Blight (NLB) and Eyespot:
Caution: In conditions where NLB and Eyespot risks are high, growers should only consider planting hybrids with at least moderate resistance ratings of 5 or higher for these diseases.

26Disease resistance ratings:
8 to 9 = Highly resistant.
6 to 7 = Resistant.
4 to 5 = Moderately resistant.
1 to 3 = Susceptible.
- = Indicates insufficient data.

Disease resistance ratings are mostly based on United States and European data as the New Zealand database is usually too small to give a statistically valid rating (except for Eyespot, NLB and Common Rust ratings which are based on overseas data and New Zealand observations where available). Scores are based on visual assessment only and not on yield reduction data.

27Cool environments:
In cool environments including high altitude sites greater than approximately 150 m/500 ft above sea level, select your growing environment using the definitions below, then increase populations to the next level e.g. for 37Y12 in a medium yield environment at high altitude, plant to achieve 102,000 plants per hectare.

28Established plant populations:
The planting populations shown in the Pioneer® brand maize for grain hybrid trait characteristics chart (on page 36) assume good seed establishment conditions. If you are planting very early or into a less than ideal seedbed or where insect pressure may be high (e.g. shorter than optimum fallow periods), planting populations may need to be increased to compensate for reduced establishment due to the higher risk of early seedling mortality.

29Growing environment definitions:
May include some or all of the following characteristics:

Challenging yield environments (CYE)

  • Light, sandy or shallow soils of low fertility, predictably low summer rainfall (drought-prone) environments.
  • Exposed sites with very high wind run.
  • High cob, leaf or stalk disease pressure.

Medium yield environments (MYE)

  • Average fertility soils with predictably adequate summer rainfall.
  • Continuously cropped soils.
  • Medium to low cob, leaf or stalk disease pressure.
  • Planting at these populations are recommended for new maize growers and food grade grain production.

High yield environments (HYE)

  • Deeper, highly fertile and well structured soils.
  • Predictably good summer rainfall, shelter from high wind run.
  • Good soils straight out of long term pasture.
  • Low or no cob, leaf or stalk disease pressure.


Trait ratingsWord and numeric alignment for yield and agronomic traits
8-9 Excellent, exceptional, outstanding, superb, impressive, industry-leading.
7 Superior, very good, strong, sound, reliable, stable, dependable, consistent.
6 Good, above average, sound, reliable, stable, dependable, consistent.
5 Average, acceptable, adequate, moderate.
4 Acceptable, slightly below average.
1-3 Marginal, susceptible, below average.
Trait ratingsWord and numeric alignment for disease and entomology traits
8-9 Highly resistant, excellent, exceptional, outstanding, impressive.
6-7 Resistant, superior, strong, very good.
4-5 Intermediate, moderate, adequate, acceptable.
1-3 Susceptible (caution on use if disease is prevalent)