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The importance of protein in the human diet justifies continued searching for new techniques and recombinations for accumulating in single wheat (Triticum aestivumL.) cultivars plant mechanisms responsible for grain protein formation. Recurrent selection within a series of crosses that involve high protein parents offers possibilities for such recombinations. High protein parents were chosen from a randomly selected group of 2,000 genotypes of the World Wheat Collection previously tested for grain protein content at Bozeman, Montana. Nine high protein genotypes from eight foreign countries were chosen and used in nine crosses. The high protein genotypes were crossed with each other or with U. S. cultivars and the two highest protein selections from F3progeny rows of each cross were then crossed in all possible combinations to provide material for a second cycle of selection. First and second cycle selections were compared with each other and with original parents for potential advances in grain protein content and grain protein yield. Second cycle progeny had higher grain protein percentages than first cycle progeny. However, except for crosses 6711, 6721, and 6724, corresponding decreases in grain yield from first to second cycle provided the same or often less grams of protein in the second cycle. Crosses 6711, 6721, and 6724, plus high protein selections from other crosses, will be used as a germplasm pool for additional selection. A comparison of parents with 27 high protein lines from the second cycle showed an average increase of 2.5% in protein content and 12.0 g/2.4 m of plant row in protein yield. If these lines continue to produce high protein levels, they will be useful in breeding programs and in additional recurrent selection cycles.

We have investigated the relative pollen‐shedding abilities of 11 hard red spring and 3 durum wheat varieties and the relationships between pollen‐shedding and other varietal characteristics. The varieties differed in amount of pollen shed, number of pollen grains/anther, percent anthers extruded, tillers/plot, fertile florets/plot, fertile florets/tiller, yield, and kernel weight. Anther extrusion varied from 72% for ‘Thatcher’ spring wheat to 22% for ‘Lakota’ durum wheat. Number of pollen grains/anther varied from 3,867 for ‘Rescue’ to 2,687 for ‘Fortuna’ spring wheat. The amount of pollen shed was positively correlated with percent anthers extruded and tillers/plot but negatively correlated with fertile florets/tiller. Path coefficient analysis indicated that percent anther extrusion had the largest direct effect on pollen shedding. Pollen shedding ability of a variety was predicted on the basis of percent anther extrusion, pollen grains/anther and fertile florets/plot.

Samples of high and low grain protein content (%) were compared from each of eight spring wheat crosses. The high protein samples were obtained by compositing 14 F3progeny rows from the high end of the F3distribution curve; the low protein samples were obtained similarly from the low end of the F3distribution curve. These composites were seeded at three Montana locations and evaluated for agronomicharacteristics and for grain and plant nitrogen to help determine the nature of the expression of grain nitrogen content in spring wheat. Grain nitrogen content was negatively related to grain yield and to the graln‐straw ratio. High and low protein composites at Bozeman produced the same amount of above ground plant nitrogen, and each translocated the same percent of nitrogen to grain. However, grain nitrogen content of the high protein composite was significantly higher because of the distribution of a similar amount of nitrogen to a smaller amount of grain. Differences in plant growth characteristics among the eight crosses seem to account for the differences in grain nitrogen content.

Combining resistance to the wheat stem sawfly (Cephus cinctusNorton) with semidwarfness and higher grain yields in wheat (Triticum aestivumL.) is a plant breeding objective in Montana. Parental and F2populations from 17 crosses of 6 standard‐height, solid‐stemmed wheat selections with three semidwarf, hollow‐stemmed selections were evaluated in the field for semidwarfness (plant height), stem solidness, and tillering. Plant height data from crosses with ‘Bonanza’ suggest additive gene action, whereas skewness for tallness from crosses with ‘Shortana’ and MT 6830 suggest either dominance or some type of epistasis. The lack of dominance hi solid‐stemmed by hollow‐stemmed crosses is considered an indication of genetic additivity for stem solidness. All parents except Shortana tillered equally; Shortana had more tillers than standard height parents ND 681, ND 683, and ND 6850. A negative relationship between plant height and stem solidness indicates that selection of solid‐stemmed, semidwarf types should be possible. The variation exhibited by these three plant characteristics offers plant breeders an opportunity to combine desirable features of each.

Parental and F2populations of 25 foreign wheats crossed with ‘Rescue,’ a solid‐stemmed variety, were evaluated for stem‐solidness. Results indicated that Rescue and the 25 foreign wheats had some stem‐solidness genes in common. Nine foreign wheats were more solid than Rescue and apparently possess a gene (or genes) which may be useful in increasing degree and stability of resistance to the wheat stem sawfly.