Increasing forage yields remains a top priority of most alfalfa (Medicago sativa L.) breeding programs, but yield trends suggest yield has stagnated over the past two decades. Little effort has been invested into capturing heterosis in alfalfa, but semihybrid breeding systems are a possible solutions to overcome forage yield stagnation. Development of alfalfa semihybrids will require identification of heterotic groups. Studies of crosses between dormant M. sativa ssp. sativa and M. sativa ssp. falcata suggest a heterotic pattern exists between the two subspecies. The objective of this study was to measure heterosis in elite sativa × falcata crosses (SFC) in relation to elite sativa × sativa crosses (SSC) and falcata × falcata crosses (FFC). Nine elite sativa clones and five falcata clones were crossed in a diallel mating design. Progeny were space planted in 1998 at Ames and Nashua, IA, and harvested for forage yield twice in 1998 and three times in 1999. A definite sativa–falcata heterotic pattern was observed. Sativa–falcata heterosis was observed at the subspecies, halfsib, and individual cross level calculated using subspecies comparisons, halfsib heterosis analysis, and combining ability analysis. On average, intersubspecific crosses yielded 18% more than the average of intrasubspecific crosses. The sativa–falcata heterotic pattern is a potentially useful resource in alfalfa breeding programs.

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This experiment was designed to determine if intercropping corn (Zea mays L.) with climbing beans is a viable option to increase crude protein (CP) concentration in forage rather than purchasing costly protein supplements for livestock rations. In these experiments, corn was intercropped with three beans—lablab bean [Lablab purpureus (L.) Sweet], velvet bean [Mucuna pruriens (L.) D.C.], and scarlet runner bean (Phaseolus coccineus L.)—or grown in monoculture near Arlington and Lancaster, WI. Corn was sown in early May and late April in 2004 and 2005, respectively, and later thinned to 55,000 (low density) or 82,500 (normal density) plants ha−1 Beans were sown in rows 8 cm on one side of the corn rows at 82,500 plants ha−1 2 or 4 wk after corn planting. Averaged over four environments, mixture forage dry matter (DM) yields were similar. However the velvet bean and scarlet runner bean mixtures produced significantly higher forage DM yield, 1.2 Mg ha−1 and 0.89 Mg ha−1 more, respectively, in the late bean planting treatment. Beans, except scarlet runner bean, which was damaged by mold and insects, increased the CP concentration of all mixtures, with the greatest increases from the lablab bean (13%) and velvet bean (16%). The experiments show that lablab bean grown with corn has the greatest potential of the three beans to increase CP concentration above monoculture corn, without compromising forage yield or calculated milk ha−1 and increasing forage nutrient value.

In many major perennial forage species, genomic tools and infrastructure development has advanced enough that their utilization in marker‐assisted selection (MAS) can be cheaply explored. This paper presents a paternity testing MAS in diploid red clover (Trifolium pratense L.). Utilizing individual plant phenotypes, known maternity, and molecular marker‐determined paternity, paternal and maternal breeding values are calculated and selection on both parents is accomplished. Paternity testing MAS is demonstrated in three red clover breeding populations utilizing permutation‐based truncation selection for a biomass‐persistence index trait. Permutation‐based truncation selection is accomplished by ranking parents based on 80% of total progeny per permutation. Parental rankings are then used to select among the remaining 20% of total progeny and average selection gains across all permutations are estimated. Paternity was determined from 11 simple sequence repeats (SSRs) amplified in two polymerase chain reactions (PCRs). Paternity‐based selection gains alone were more than double selection gains based on maternity alone. Inexplicably, the estimated paternal halfsib family additive genetic variance was four to five times greater than the maternal halfsib family additive genetic variance. Paternity testing MAS is implementable in other diploid forage species and allopolyploid forage species with one diploid genome and corresponding genome specific molecular markers.