Varietal Hybrids: Why and How

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1 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: Why and How PascoM2/LH198 NC PascoM2/UR1M1

2 Varietal hybrids: crosses between populations or varieties.

3 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.

4 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.

5 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.

6 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.

7 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.

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

9 Corn that resists transgene contamination There are two gene systems (from popcorn and teosinte) that naturally convey gametophytic incompatibility. 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.

10 MFAI s breeding strategy for varietal hybrids 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.

11 Step 1: Find out which varieties cross well together! Top 12 out of 73 entries grown on 7 sites in 2004 in Iowa and Wisconsin Entry bu/acre moisture NC+ Organic Hybrid AR17056:N2025SynS/BS NC+ Organic Hybrid CUBA117:S1520SynS/BSCB BSCB1/BS AR16026:S17SynS/BSCB FS8B(S):S0316SynS/BSCB FS8B(T):N1802SynS/NokomisGold CH05015:N12SynS/BS AR17056:N2025SynS/NokomisGold FS8B(T):N1802SynS/BS Nokomis Gold 91 21

12 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

13 Step 3: Look for crosses that yield 90+% of good commercial hybrids. Variety Yield Moisture %RL %SL WENSMAN 5048 Bt HYLAND SEEDS Bt Cargill BS21/CGSS BS21/CGL BS22/CGSS BS21/BS Some varietal hybrids performed well in multilocation tests in North Dakota (Carena, NDSU)

14 Best varietal hybrid in Iowa tests Rank Variety Yield %H2O Pollak: Central Iowa 1st NC+ 42A nd BSS(R)C15/BSCB1(R)C Lamkey: Southern Iowa 1st RX th BSS(R)C15/BSCB1(R)C Lamkey: Central Iowa 1st DKC th BSS(R)C15/BSCB1(R)C

15 SARE Project on OP Corn in New York Milk/ton Milk/Acre Pioneer 38T27 Pioneer 38K06 Wapsie Valley Nokomis Gold E95 Minnesota 13 BS22/BS21 NDSAB Smith and Mt Pleasant (Cornell) found two OP varieties and a varietal hybrid (BS22/BS21) had potential as silage.

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

17 Summary Taste and feed quality Low seed cost: easy to produce organic seed Suitability for sustainable agriculture conditions (soils & weeds) Adaptable to locale Specialty markets Independence