PascoM2/LH198 NC+ 3448 PascoM2/UR1M1

Varietal Hybrids: Why and How…

Walter Goldstein, Michael Fields Agr. Institute; with contributions from L. Pollack, USDA/ARS; K. Lamkey, ISU; M. Smith and J. Mt Pleasant, Cornell; M. Carena and F. Kutka, NDSU.

Varietal hybrids: crosses between populations or varieties.

Varietal hybrids: crosses between populations or varieties.

• Yields: usually OP<Varietal<SC, though some varietal hybrids are competitive with commercial SC hybrids.

• They are easier to produce than SC hybrids under organic conditions. The variety parents are more competitive with weeds.

Varietal hybrids: crosses between populations or varieties.

• Faster to develop than SC hybrids once good crosses are identified.

• Farmers can adapt the OPV parents and resulting hybrids to their own farms and management systems.

• Varietal hybrids provide a way of quickly boosting yield and addressing unique marketing options.

Easier to produce seed: In Wisconsin in 2005, seed yield from variety parents was 50 bu/acre while inbred parents yielded 22 bu/acre. The varieties competed better with weeds.

High methionine corn: Organic poultry need corn with more methionine. We have bred for this trait and we intend to release these varietal hybrids by 2008.

High protein corn: Linda Pollak and her USDA colleagues breed for higher protein and oil content in populations and for high yielding varietal hybrids.

Mungoma and Pollak, 1988: Yield of Mexican Dent/BSSS (139 bu/A) not significantly different from highest yielding hybrid check.

High carotenoid corn: These powerful anti-oxidants and vitamin A precursors turn egg yolks and poultry skin orange. We select for orange corn!

Corn that resiststransgene contamination

• There are two gene systems (from popcorn and teosinte) that naturally convey “gametophyticincompatibility.”

• Margaret Smith at Cornell has been breeding one of these genes into inbreds.

• Walter Goldstein (MFAI) and Linda Pollack (USDA/ARS) are breeding these genes into corn populations for varietal hybrids and also into inbreds.

• Step 1: Develop high-quality, adapted populations with good agronomic traits, and find out which ones cross well together.

• Step 2: Breed these pairs so that when they are crossed the hybrids produce at least 1/3 more than the average yield of the parents without losing grain quality.

• Step 3: Optimize these varietal hybrids so they produce 90+% of commercial single cross hybrids.

MFAI’s breeding strategy for varietal hybrids

Top 12 out of 73 entries grown on 7 sites in 2004 in Iowa and WisconsinEntry bu/acre moistureNC+ Organic Hybrid 2 116 19AR17056:N2025SynS/BS13 113 21NC+ Organic Hybrid 1 102 19CUBA117:S1520SynS/BSCB1 101 23BSCB1/BS13 100 23AR16026:S17SynS/BSCB1 100 22FS8B(S):S0316SynS/BSCB1 96 24FS8B(T):N1802SynS/NokomisGold 96 22CH05015:N12SynS/BS13 95 23AR17056:N2025SynS/NokomisGold 94 20FS8B(T):N1802SynS/BS13 92 25Nokomis Gold 91 21

Step 1: Find out which varieties cross well together!

Step 2. Recurrent selection to make two populations yield better together in a hybrid cross:

In 2002, Nokomis Gold X AR21B (AR16021:B73) yielded 150 bu/acre; at least 50 bushels more than either parent. We began to select both parents for their ability to combine and produce yieldy hybrids while working to improve their earliness, standing ability, and yield. We are doing the same thing with Nokomis and population FS.

AR21B Nokomis Gold

Some varietal hybrids performed well in multi-location tests in North Dakota (Carena, NDSU)

3.1026.4118BS21/BS22

7.91.119.5119BS22/CGSS

6.91.420.5122BS21/CGL

9.00.118.6127BS21/CGSS

7.20.317.5130Cargill 1877

3.83.717.4132SEEDS 2000 2871 Bt

8.05.916.7135HYLAND 2305

2.70.917.4137WENSMAN 5048 Bt

%SL%RLMoistureYieldVariety

Step 3: Look for crosses that yield 90+% of good commercial hybrids.

Best varietal hybrid in Iowa tests

17.9135NC+ 42A321st17.4131BSS(R)C15/BSCB1(R)C152nd

18.0152BSS(R)C15/BSCB1(R)C1512th

15.6171DKC53-331stLamkey: Central Iowa

15.4141BSS(R)C15/BSCB1(R)C159th

15.2167RX7151stLamkey: Southern Iowa

Pollak: Central Iowa%H2OYield VarietyRank

SARE Project on OP Corn in New York

350035503600365037003750380038503900

Pioneer

38T27

Pioneer

38K06

Wap

sie V

alley

Nokom

is Gold E95

Minneso

ta 13

BS22/B

S21NDSAB

0

5000

10000

15000

20000

25000

30000

35000Milk/tonMilk/Acre

Smith and Mt Pleasant (Cornell) found two OP varieties and a varietal hybrid (BS22/BS21) had potential as silage.

Growth Type we need and are seeking:Vigorous, lax leaved, leafy, and allelopathicto compete with weeds.Good fertility. Uniform maturity.Good roots and stalks.Stay-green and timely dry-down.

SummaryTaste and feed quality

Low seed cost: easy to produce organic seed

Suitability for sustainable agriculture conditions (soils & weeds)

Adaptable to locale

Specialty markets

Independence