1Silage comparative relative maturity (CRM): Pioneer silage CRM ratings provide a comparison between Pioneer hybrids indicating the relative rates at which hybrids reach harvestable whole plant drymatter. They do not represent actual calendar days from planting to harvest.
2Yield for maturity: Hybrid comparisons should only be made within a range of + or – 4 CRM. Analysis of differences in harvest drymatter percentages between hybrids measured in our New Zealand silage research programme show products compared within + or – 4 CRM will reach ideal silage harvest maturity (defined as 30% - 38% DM) within about seven days of each other.
3Adaptability 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 high yields.
4Adaptability to low population: An indicator of a hybrid's ability to compensate (flex) cob size for stand loss from insect damage or poor emergence.
5Early growth: Ratings are taken when two leaf collars are visible.
6Plant height: 9 = Tall. 1 = Short.
7Staygreen: A measure of late season plant health. A lower score also means that the plant stover loses colour and dries down more rapidly at maturity.
8Whole plant digestibility: Based on estimated 24 hour in vitro, whole plant digestibility percentage (DM basis) as predicted by Near Infrared Reflectance Spectroscopy (NIRS).
9Starch and sugar: Based on total starch and sugar of hybrids harvested at silage maturity. Use this score as a relative comparison of the whole plant concentration of more readily available energy (primarily grain) among individual hybrids.
10Northern 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.
11Hybrid disease resistance ratings: 8 to 9 = Highly resistant. 6 to 7 = Resistant. 4 to 5 = Moderately resistant. 1 to 3 = Susceptible. - = Insufficient data.
Common Rust, Eyespot and LB ratings are based on overseas data together with New Zealand observations. Scores are based on visual assessment only and not on yield reduction data.
12Cool environments: In cool environments, including high altitude sites greater than approximately 150 m / 500 ft above sea level, select your yield environment using the descriptions in note 17, then increase established plant populations to the next level i.e.for P0791 in a medium yield environment at high altitude, plant to achieve 108,000 established plants per hectare.
13Established plant populations: These 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. a shorter than optimum fallow period), seeding rates may need to be increased to compensate for reduced establishment due to field losses.
14Plant populations: The tabulated established populations are recommendations only. Work with your local Pioneer representative or Merchant seed representative to determine the appropriate plant populations for your specific growing environment.
15Growing environment definitions: May include some or all of the following characteristics:
Challenging yield environments (CYE)
- Typically light, sandy or shallow soils of low fertility, low moisture retention, and predictably low summer rainfall (drought-prone environments).
- High cob or leaf disease pressure.
Medium yield environments (MYE)
- Average fertility soils with predictably adequate summer rainfall and good moisture retention.
- Continuously cropped soils.
- Medium to low cob or leaf disease pressure.
High yield environments (HYE)
- Typically deeper, highly fertile and well structured soils with good moisture retention.
- Predictably good summer rainfall, shelter from high wind run.
- Good soils straight out of long term pasture.
- Low or no cob or leaf disease pressure.
% = Percent
g = gram
m = metre
cm = centimetre
kg = kilogram
ha = hectare
DM = drymatter
bags/ha = bags per hectare
kgDM = kilograms of drymatter
kgDM/ha = kilograms of drymatter per hectare
kgMS = kilograms of milksolids
kgMS/cow = kilograms of milksolids per cow
$/ha = NZ dollars per hectare
MJME = megajoules of metabolisable energy
MJME/kgDM = megajoules of metabolisable energy per
kilogram of drymatter
t/ha = tonnes per hectare
tDM = tonnes of drymatter
tDM/cow = tonnes of drymatter per cow
tDM/ha = tonnes of drymatter per hectare
c/kgDM = cents per kilogram of drymatter