Seed Supply Update--Matching Seed Size to Your Planter  02/21/18 4:31:50 PM

Marker assisted breeding (MAB) or marker aided selection (MAS) is a process whereby a marker (for our purpose one based on DNA/RNA variation) is used for indirect selection of a genetic determinant or determinants of a trait of interest  (i.e. plant disease tolerance, yield, etc)  Marker assisted selection (MAS) is indirect selection process where a trait of interest is selected not based on the trait itself but on a marker linked to it.  For example if MAS is being used to select genetic lines with a disease, the level of disease is not quantified but rather a marker allele (DNA strand) which is linked with disease is used to determine disease presence. The assumption is that linked allele associates with the gene and/or quantitative trait of interest.  MAS can be useful for traits that are difficult to measure, exhibit low heritability, and/or are expressed late in development—many times equating to yield potential.
Confusing??  Somewhat, however, I mention all of that to really “frame up” some of the breeding back ground and differences between DeKalb/Asgrow vs competitive brands. 
Consider this:
Asgrow developed the first soybean variety developed using molecular marker technology to select for pest resistance and was released by Monsanto in the late 1990's.   
Asgrow—developed the first lines advanced using marker technology to select for regions with higher yield were advanced in the fall of 2005.    Since this initial release, the number of varieties developed using markers to improve the efficiency of the breeding process has increased significantly.  
Asgrow/DeKalb utilizes a sophisticated seed chipper developed “in house” that is capable of evaluating 100 million seed lines per year—ALWAYS looking for the next best thing.
So, when you hear/see advertisements surrounding Asgrow and DeKalb, be confident that there is a combination of historic research with cutting edge breeding techniques and local performance data to insure you have made the right brand choices.
Seed Supply Update—Every winter about now questions circle around seed supply of corn from a number of brands.  This brings up the question of where are we on a supply standpoint?  From a DeKalb standpoint, some hybrids that had outstanding performance in 2016 and 2017, are now out of supply.  (See below for the reasons why are out).  This again happens every year to some degree. I have ample supply of hybrids such as DKC52-61 and DKC60-88, DKC61-88, DKC62-98, DKC63-55 DKC64-35 that have continued to perform well.
DKC70-27SOLD OUT-- 228.2 bu./A 67% Top 3 & 86% Top Half of 2017 plots– is the LEADER plot running average, though it’s not quite the gap that it had in ’16.
A consistent performer---here is 2016’s numbers--73% in the Top 3 and 91% in the top half (it’s the #1 hybrid in 55% of the plots it’s in)
DKC66-75--SOLD OUT---New for 2018---227.2 bu./A 64% Top 3 & 92% Top Half of 2017 plots – is in a solid second place, with great overall consistency, (just 1 bushel off of DKC70-27 on overall running average). 
DKC65-81 – ---SOLD OUT--222.6 bu./A 58% Top 3 & 78% Top Half of 2017 plots
There are still good choices available
DKC64-35 – 222.5 bu./A 36% Top 3 & 81% Top Half of 2017 plots–It’s standability/intactness is incredible after the miserable 2017 harvest weather. This hybrid should be on everyone’s order!  
DKC65-94 – 216.7 bu./A 6% Top 3 & 56% Top Half of 2017 plots--it had a solid first year competing against the best DKC lineup I’ve ever seen.  Great plant health here as well. 
DKC60-88 – 215.0 bu./A 17% Top 3 & 53% Top Half of 2017 plots–   How often do you see a 110 RM corn stay consistently with the industry leading 120, 116, 115, and 114 day hybrids?
Asgrow soybean supply is generally good of proven performers such as AG32X8 AG33X8 AG37X8, AG39X7.  (See below)
AG36X6 –supply limited-- 65.9 bu./A – 52% Top 3 & 90% Top Half – still the King but, (due to an incredibly strong class of 6 new products), it isn’t showing quite the insane dominance it did in 2016.  It’s still just as awesome as it was in 2016, the class of ’18 is just joining it at the top of the plots.  Plant this bean anywhere.  Strong SDS and PRR ratings with great standability.  Outstanding yield in all conditions.
AG37X8 – 63.8 bu./A – 29% Top 3 & 81% Top Half – looks to be the best of the class of ’18 and a great replacement for AG3832 & AG3731 with a lot of versatility.  Solid SDS & PRR defense with great standability and a consistent yield advantage across all environments.
AG33X8 – 63.1 bu./A – 33% Top 3 & 52% Top Half – shows a lot of the high yield potential of AG32X7, but perhaps not the same stress tolerance.  Steer this bean toward the better acres.  Strong SDS, PRR, & BSR package.  This bean is a great fit for all those acres where AG3432 & AG34X7’s yield really well but lay down.
AG32X8 – 62.2 bu./A – 33% Top 3 & 67% Top Half – a great early RM bean for the majority of southeast Nebraska acres.  Defensive package includes SCN, PRR, & BSR.  Solid replacement for AG3034 & AG3231 with similar standability but better crop canopy and yield.  Just a step behind AG33X8’s in yield, but it fits more acres with its more stable consistency in lower yield environments.
Rounds or Flats: Which Corn Seed is Better?
Size Description Approx. Bag Weight*  
AF AccuFlat 38-50    
AF2 AccuFlat 45-57    
AR AccuRound 38-50    
AR2 AccuRound 48-60    
* Estimate provided as bag weight can vary among
corn hybrids.      
.“My planter works best with 45 lb AR seed”  OK.  Everyone has their reasons.   Equipment today continues to make strides towards decreasing the impact of the size and weight of the seed and impact it might have for stand establishment, etc.   Corn seed size and shape on the same ear will vary due to genetics, the environment, and location of kernels on the ear.
Genetic Potential. Numerous studies have been conducted over the years that well documented . Hybrid corn seed size or shape has nothing to do with the genetic yield potential of the hybrid. Small corn seed has been associated with slight delays in tasseling or silking, but this has seldom translated into yield losses.
Seed Quality. Crop stress including high temperature, low soil moisture, or low fertility can decrease hybrid seed size. Additionally, placement of seed on the ear affects both seed size and viability because of the sequential development of the corn ear from the base to the tip and the variation in photosynthate availability to each kernel, seed from a single ear can fall into many size/shape categories. Large-round classes usually come from the base of the ear, flats from the center, and small-round seed from the tip.  Results from a wide variety of scientific field studies suggested that corn producers should focus on genetic potential and seed quality rather than specific seed sizes or shapes when selecting corn hybrids.
Plantability. The most important factor involving seed size effects on yield relates to plantability issues. Plantability problems often occur if planters are not adjusted for the seed size being used. Excessive numbers of doubles (two seeds dropped at the same time) or skips can easily reduce grain yield by 3 to 10 bushels per acre. Therefore, get the most out of the seed corn you purchased this year and calibrate each seed lot separately before the hectic planting season starts. Your corn yields will like you for it!
Sources: R. Nielsen. 1996. Seed size, seed quality, and planter adjustments. Online source: c9606.htm
Graven, L.M. and P.R. Carter. 1990. Seed size, shape, and tillage system effect on corn growth and grain yield. Journal of
Production Agriculture 3: 445-452.

Copyright DTN. All rights reserved. Disclaimer.
Powered By DTN