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1.
Summary Fifty lines of oats (Avena Sativa L.) with a broad range of nitrogen harvest indexes (NHI) and nine check lines were evaluated in 15 environments to study the association between NHI and adaptability of oat lines to soils with different productivity levels due primarily to different amounts of N. Three yield characteristics (i.e., mean across environments, regression response to improving environments, and stability of response) were used to measure adaptability. The lines were significantly variable for means of grain and straw yield, for responsiveness to improving environments, and for stability of yield. Among the yield characteristics, only the mean of grain yield was significantly correlated with NHI.Journal Paper No. J-13336 of the Iowa Agric. and Home Econ. Exp. Stn., Ames, Iowa, 50011. Project 2447. 相似文献
2.
Summary Relationships that exist among grain yielding ability and response and stability of grain yields when tested over variable environments were examined. Two sets of oats lines were tested over many environments that had wide ranges in productivities. The lines in each set were divided into high-, medium-, and low-yielding groups on the basis of means across all environments, and variance components for genotype × environment interactions and means of regression responses and coefficients of determination were computed for the three yield categories in each set.Mean grain yields for the high-, medium-, and low-yielding groups across both sets of oats lines were 2.7, 2.3, and 1.9 Mg ha-1, respectively. Coefficients of variability for the genotype × environment interaction were 18%, 16%, and 12% for the high-, medium-, and low-yielding categories, respectively. Means for regression responses were 1.22 for the high group, 0.99 for the medium, and 0.78 for the low. Most responses for the high and low groups were significantly different from 1.0. Means for coefficients of contingency were 0.63, 0.56, and 0.51 for the high-, medium-, and lowyielding groups, respectively.There was a positive relationship between mean grain yield and response of grain yield to improving environments. Thus, high yielding lines are also the responsive lines. Our study gave conflicting results about stability of production for the three yield groups. Coefficients of variation for genotype × environment interaction indicated that the high-yielding group was more interactive with environments than were the medium- and low-yielding ones: However, the means for coefficients of contingency indicated that the high yielding group was the most stable.Journal Paper No. J-12128 of the Iowa Agric. and Home Econ. Exp. Stn., Ames, IA 50011. Project 2447. 相似文献
3.
J.B. Holland Å. Bjørnstad K.J. Frey M. Gullord D.M. Wesenberg T. Buraas 《Euphytica》2000,113(3):195-205
In order to test if selection can improve a population's adaptation to diverse environments simultaneously, three cycles of
recurrent selection based on grain yield in Iowa, Idaho, and Norway were practiced in an oat (Avena sativaL.) population developed from North American, Scandinavian, and wild species (A. sterilis L.) germplasm sources. Specific objectives were to determine if selection: increased mean yields across environments and
within all environments; changed the genetic correlation of yields in different environments; and changed genetic variation
for yield within the population. We evaluated 100 to 210 randomly-chosen families from each cycle of selection at three Iowa
locations, in Idaho, and in Norway for two years. Grain yield within each location and mean yields across locations increased
significantly over cycles of selection. Mean yields across locations expressed as a percent of the original population mean
increased at a rate of 2.6% per year. Several families from the third cycle population exhibited both high mean yields across
locations and consistently high yields within all locations. Average genetic correlations of yield in different environments
were higher in the second cycle than in the original population. A trend of reduced genetic variation and heritability was
observed in Iowa only. These results suggest that we successfully improved mean population yield both within and across locations,
and yield stability across environments, and in developing families with outstanding adaptation to diverse environments.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
4.
Summary Recurrent selection programs can be manipulated by varying either the extensiveness of testing used to identify superior lines or the number of intermating generations conducted among the superior lines between cycles of selection. The research was conducted to compare the performance of soybean (Glycine max (L.) Merr.) lines derived from populations developed by recurrent selection for seed yield using a factorial arrangement that combined one or two stages of replicated yield testing to identify superior lines with one or three generations of intermating among the selected lines. The base population AP6, which was used for this evaluation of alternative strategies of recurrent selection, was derived from 40 high-yielding strains of Maturity Groups 0 to IV. For this study, the 40 original parents of AP6 and the lines used as the parents for the most advanced cycle of selections for each of the strategies were evaluated in four Iowa environments. The number of cycles of selection completed for the strategies under evaluation varied from two to five. Strategies with two stages of replicated yield testing to select superior lines resulted in a larger number of high-yielding lines than when only one stage of testing was conducted. A larger number of high-yielding lines was obtained from strategies with one generation of intermating than when three generations were used. With the procedures used for the one-stage and two-stage tests in this study, the results indicated that an appropriate strategy for recurrent selection of seed yield in soybean would involve two stages of replicated yield testing to identify superior lines and one generation of intermating among the selected lines to form a new population.Journal Paper no. J-12025 of the Iowa Agriculture and Home Economics Experiment Station, Projekt 2475, Ames, IA. 相似文献
5.
Summary The objectives of this study were to evaluate the efficacy of S1-recurrent selection for increasing groat (caryopsis)-protein yield in oat (Avena sativa L.) and to compare the effects of three selection strategies on correlated responses in groat yield and groat-protein concentration. Three S1-recurrent selection programs were conducted for five cycles. Selection criteria in each program (line of descent) emphasized different components of protein yield; high grain yield in HG, both high grain yield and high groat-protein concentration in HP, and protein yield per se in HGP. Thirty to sixty random S0-derived lines from each cycle and ten check lines were evaluated in one year at two locations to estimate the response to selection. Groat-protein yield increased 4.4% cycle-1 in HG, 3.4% cycle-1 in HP, and 2.2% cycle-1 in HGP. Gains in groat yield were 7% cycle-1 in HG, 1% cycle-1 in HP, and 3% cycle-1 in HGP. Mean groat-protein yield and groat yield in the cycle 5 (C5) populations of all three lines of descent were equal to or slightly higher than those of high yielding cultivars. The HG line of descent showed a significant decrease from 193 to 175 g kg-1 groat protein, while the HP line of descent showed a significant increase from 202 to 218 g kg-1. The HGP line of descent showed a small but significant decline in groat protein from 200 to 192 g kg-1. In comparison, the high-protein commercial cultivars contained about 210 g kg-1 groat protein. The C5 population of the HP line of descent had a unique combination of high groat yield and high groat-protein concentration. Genotypic variances for groat-protein yield, groat yield, and groat-protein concentration were not always significant in the various cycles of the three lines of descent, but in no instance was there a consistent change from C0 to C5. S1-recurrent selection was effective for increasing groat-protein yield of oat, and with the proper germplasm and selection strategy both groat yield and groat-protein concentration can be improved simultaneously.Abbreviations C -
cycle
- GPC -
groat-protein concentration (a groat is the part of an oat grain that is the actual seed or caryopsis, rather than the hull)
- GPY -
groat-protein yield
- GTY -
groat yield
- HG -
selection for protein yield through high grain yield
- HGP -
selection for protein yield per se
- HP -
selection for protein yield through high grain yield and high protein concentration
Journal Paper No. J-15287 of the Iowa Agriculture and Home Economics Experiment Station, Ames, IA 50011, USA. Project No. 2447. 相似文献
6.
Summary In breeding crop varieties for stress environments, it must be decided whether to select directly, in the presence of stress, or indirectly, in a nonstress environment. The relative effectiveness of these two strategies depends upon the genetic correlation (r
g
) between yield in stress and nonstress environments and upon heritability in each. These parameters were estimated for grain yield of 116 random oat lines grown in nonstress, P-deficient, N-deficient, and late-planted environments. Estimates of r
g
between yield in nonstress and yield in P-deficient, N-deficient, and late-planted environments were 0.52±0.24, 1.08±0.16, and 0.06±0.24, respectively. No consistent relationship between heritability and environment mean yield was observed. Direct selection in the presence of stress was predicted to be superior for yield in low-P and late-planted environments, but indirect selection in high-N environments was predicted to be as effective as direct selection in producing yield gain in low-N environments. These results confirm that neither high-yield environments nor environments in which the heritability of yield is maximized are necessarily optimum when the goal is to maximize yield gain in stress environments.Dep. of Agronomy, Iowa State Univ., Ames, IA 50011; USA, Journal Paper no. 13101. Project 2447. 相似文献
7.
Summary Test weight, seed weight, and groat percentage are three common measures of grain quality for oat (Avena sativa L.). There is considerable disagreement, however, about the utility of each of these traits as measures of grain quality, so it is important to understand the genetic interrelations among them and between them and other agronomic traits. In this study, 50 random F2-derived F3 lines from each of 13 biparental oat crosses were evaluated. Genotypic variances, heritabilities, and genotypic correlations for test weight (TW), seed weight (SW), groat percentage (GP), grain yield (GY), harvest index (HI), plant height (PH), and date of heading (DH) were used to predict and compare direct and indirect gains from single-trait selection. Direct selection was always the most effective method for improving single traits; average predicted improvement of population means was 4% for TW, 10% for SW, 1% for GP, and 14% for GY when 10% selection intensity was applied. Genotypic correlation coefficients, averaged for all crosses, were 0.04 for TW with SW, 0.37 for TW with GP, -0.09 for SW with GP, and 0.29, 0.36, and 0.30 for GY with TW, SW, and GP, respectively. Thus, direct selection for TW, SW, or GP should not greatly affect the other two grain quality indicators. For the seven traits considered, there seemed to be no large advantage or disadvantage, in terms of correlated responses, associated with selection for any of the grain quality indicators.Contribution as Journal Paper No. J-14650 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa. Project No. 2447. 相似文献
8.
Summary The paper addresses the general question of identifying the optimum environment for selection in plant breeding programs for low input agricultural systems. After defining low-yielding and high-yielding environments based on the average grain yield of large numbers of barley genotypes in different cropping seasons, we examined: 1) the phenotypic relationships between the highest yielding genotypes in low- and high-yielding environments, and 2) the genetic correlation coefficients between grain yield in low- and high-yielding environments. The results indicate that the alleles controlling high grain yield in low-yielding conditions are at least partially different from those controlling high grain yield in high-yielding conditions. Therefore, selection in high-yielding environments is expected to produce a negative response or no response in low-yielding environments. This may explain why crop varieties bred under high-yielding conditions failed to have an impact in low-yielding agricultural systems. The results may be extrapolated to systems where environmental concern suggests a reduction of inputs by raising the question of whether crop breeding programs based on selection under high inputs are likely to generate the right type of germplasm for an environmentally friendly agriculture. 相似文献
9.
Summary Relationships among the traits protein percentage, grain yield, and protein yield of oats were studied with F2-derived lines in F3 and F4 from 27 matings obtained by crossing high-protein with high-yield oat lines. High-protein parents were (a) selections from an Avena sativa bulk, (b) selections from three-way matings in which an initial parent was A. sterilss, and (c) cultivars. High-yield parents were derived from backcross populations involving A. sterilis accessions as donor parents.Significnnt genetic variation existed among F2-derived lines for grain and protein yield in all matings and for protein percentage in all but one mating.Protein percentage had a highly significant negative correlation with grain yield (r=–0.33**) when pooled over all matings, but in five, these two traits were not correlated. Overall, protein percentage showed a small negative correlation with protein yield (r=–0.09*), and protein and grain yields had a high positive association (r=0.98**). F2-derived lines with both high protein percentage and high grain yield were obtained.High transgressive segregates for protein percentage occurred in two matings, for grain yield in nine, and for protein yield in 14. Most high transgressive segregates for protein yield were high because of high grain yield only, but in four matings, lines were found where protein yield was increased by concurrent increases in both protein percentage and grain yield.Only a few specific parental combinations between high-protein and high-yield parents produced segregates in which increased protein percentage contributed materially to high-protein yields.Journal Paper No. J-11264 of the Iowa Agriculture and Home Economics Experiment Stn., Ames, Iowa 50011. Project 2447. 相似文献
10.
Summary Most variation in grain yield of oats is due to variation in harvest index and vegetative growth index, but the latter traits are negatively associated. Therefore we used independent culling levels to select oat genotypes with high levels of vigor traits and a desirable level of harvest index in an attempts to maximize grain yield. Harvest index and vegetative growth index or harvest index and unit straw weight were selected at various culling levels. Intensive selection for harvest index resulted in high harvest index but no grain yield improvement, because the selected lines had poor vigor. Intensive selection for vegetative growth index or unit straw weight resulted in high biomass but low harvest index.The most effective combination of culling levels was to select 25% of the original population for harvest index and, subsequently, to select for vegetative growth index or unit straw weight at an 8% intensity in the remnant population.Journal Paper No. J-11272 of the Iowa Agric. and Home Econ. Exp. Stn., Ames, IA 50011. Project 2447. This work was supported in part by the World Food Institute, Iowa State Univ., in the form of a Senior Fellowship for the senior author. 相似文献
11.
Summary One hundred random oat (Avena sativa L.) lines from a base (C0) and each of three populations (C1, C2, and C3) improved for groat (caryopsis) oil content by phenotypic recurrent selection were evaluated for correlated changes in several unselected agronomic traits. In addition, the parents of the base population and four check varieties were evaluated for the same traits. Phenotypic recurrent selection for high groat-oil content resulted in no significant correlated response in mean expression of any trait. Mean grain yield, biomass, groat yield, and harvest index of the improved populations were equal or superior to the mean of the parents and, with the exception of harvest index, equivalent to the mean of the check varieties. Mean test weight and seed weight of all populations were lower than for parents or check varieties. Selection for high groat-oil content caused a decline in genotypic variance for test weight and groat fraction, but reductions in genotypic variance for heading date and plant height may have resulted from culling for good agronomic type. Broad-sense heritability remained moderate to high for all traits except groat fraction. Phenotypic and genotypic correlation coefficients revealed negative, though mostly nonsignificant, relationships between groat-oil content and several traits, which may reflect a purported bioenergetic limitation to increasing groat-oil content in oats. Oil yield, however, was positively correlated with grain and groat yield, groat fraction, biomass, and harvest index. Results suggest that development of high-oil oat cultivars with current levels of production traits via phenotypic recurrent selection is possible.Journal Paper no. J-13038 of the Iowa Agric. and Home Econ. Exp. Stn., Ames, IA 50011. Project 2447. 相似文献
12.
Summary Yield data were collected for soybean (Glycine max (L.) Merr.) lines in maturity groups III and IV in 14 environments from 1985 to 1989. The lines in each maturity group were subdivided into three different groups based on the mean yield over all environments, and the genotype × environment interactions were studied for each group. Yield stability of the lines was determined. Effectiveness of selection based on different types of environments was examined.Productivity level of the environment did not influence the relative ranking of the lines. Significant rank correlations occurred between mean yields in most environments and the overall mean yield, but few similarities occurred in the line rankings among individual environments. High-yielding lines contributed a significantly smaller proportion to the genotype × environment interaction than medium- and low-yielding lines.A small proportion of the lines were below or above average stability. Significant correlations occurred among stability, overall mean yield, and mean yield in high- and low-yielding environments. However, few significant correlations occurred between individual environment yields and stability in high- or low-yielding environments. Maturity groups differed in yield and stability relationships. Stability in high- and low-yielding environments did not adequately predict stability for each other.Contribution No. 93-445-J from the Kansas Agricultural Experient Station 相似文献
13.
Summary Improved grain yields in lines of oats from matings of Avena sativa x A. sterilis were found to be due to increased plant growth rate. Growth rates of oats were quantitatively inherited, with the minimum number of effective factor pairs segregating in the interspecific matings ranging from 3 to 9. Heritability values for this trait averaged 0.4. Growth rate was highly and positively correlated with bundle weight, straw yield, grain yield, and unit straw weight, but it was uncorrelated with heading date and harvest index. Correlations with plant height were low. Thus, it should be possible for oat breeders to combine the high growth rates from A. sterilis with any combination of agronomic traits.Journal Paper No. J-8608 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa 50011. Project 1752. Supported in part by a grant from the Graduate College.Hirosaki University, Hirosaki, Japan (formerly Visiting Scientist at Iowa State University). 相似文献
14.
A recurrent selection program for adaptation to diverse environments was successful in improving mean oat (Avena sativa L.) grain yield within and across testing environments. The objectives of this research were to determine if this selection
program also resulted in changes in other agronomic traits or altered yield stability. Additionally, we investigated how selection
modified the response of genotypes to climatic conditions. We evaluated random samples of 100 families from the original population
and each of three selection cycle populations in replicated yield trials in Idaho, Iowa, and Norway for two years. Yield stability
was assessed via joint regression analysis and superiority analysis. For each cycle, genetic relationships among yields observed
indifferent environments were assessed by estimating phenotypic correlations between pairs of target environments. The effect
of climate variables on genotype-by-environment interaction (GEI) responses was determined with partial least squares regression.
Selection resulted in a small increase in mean heading date, a decrease in mean test weight, and no change in total above-ground
biomass or plant height. Genotypic regression coefficients on environmental indices and deviations from regression were larger
in the last cycle population, but superiority analysis demonstrated that selection significantly improved the adaptability
of the population to the target testing environments. Improved adaptation was also demonstrated by increased phenotypic correlations
among the most divergent pairs of environments in the later cycles. Partial least squares regression of GEI effects on climate
variables suggested that later cycle families tended to respond more favorably to cooler than average conditions than the
original population. Selection resulted in improved yield stability as well as improved mean yield.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
15.
Summary Two lines of descent were established from an F3 bulk lot of oats (Avena sativa L.) initiated by mixing seeds from approximately 250 crosses. For one line of descent, seeds were radiated with thermal neutrons or X-rays from F3 through F6, followed by five generations of bulk propagation. The second was propagated for 10 generations. No artificial selection was practiced in either line of descent. Grain yield data from 20 random strains from each of four generations from the radiated (F7, F8, F9, and F11) and five from the nonradiated (F3, F6, F7, F8, and F12) line of descent and 20 check cultivars tested in 14 environments were used for estimating regression stability indexes of oat strains.The 14 environments were assigned randomly to two sets of seven, and regression stability indexes were computed for the 180 experimental oat strains for both sets. Intrageneration correlations between regression stability indexes from the two sets of environments ranged from –0.35 to 0.64 (18 d.f.), and only one of nine was significant, indicating poor repeatability for estimates of this statistic computed from different sets of environments.Correlations between regression stability indexes from two sets of environments, one in which the environments varied by soil nitrogen levels and a second in which they varied by soil phosphorus levels, ranged from –0.01 to 0.28, none of which was significant.The relative magnitudes and ranking of the regression stability index values for the oat genotypes were nearly identical when environmental productivity indexes were assessed with any number of check cultivars from 2 to 20.Journal paper No. J-8080 of the Iowa Agriculture and Home Economics Experiment Station. Ames. Iowa. USA 50010. Project 1752. 相似文献
16.
Summary We tested three sets of oat varieties for grain yield in a series of environments and observed that generally more than 80% of the yield variation for individual varieties was due to linear regression response. Mean yields for varieties were significantly variable in all three sets, and regression response indexes were significantly variable in two of them.Mean yields over the three sets were correlated with regression response indexes with r=0.61. Associations of mean yield with the three stability parameters (i.e., coefficient of determination, mean square for deviations from regression, and ecovalence) were low and usually not significant. The correlation of regression response indexes with coefficients of determination was 0.42, but neither of the other stability parameters was associated with the response indexes. The three stability parameters were closely correlated with one another.Our materials were selected varieties, so evidently our results suggest what can be accomplished in breeding for combinations of mean production, production response, and productiom stability.Journal Paper No.J-9092 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa, USA 50011. Project 1752. This work was supported in part by the International Atomic Energy Agency, vienna, Austria, in the form of a fellowship for the senior author. 相似文献
17.
Estimates of selection parameters associated with harvest index in oat lines derived from a bulk population 总被引：2，自引：0，他引：2
Summary Harvest index of grain crops is defined as grain yield divided by total plant yield. We estimated the heritability percentages of harvest index and its components, grain yield and plant weight, the genotypic and phenotypic correlations among these three traits, and the genotypic correlations of harvest index with plant height, 100-seed weight, grain number, and heading date by using a population of 1200 F9-derived oat lines tested in six environments. Furthermore, we examined the relative selection efficiencies of indirect selection for yield through harvest index and of index selection for yield through yield plus harvest index.Heritability percentages were computed by use of variance-component, standard-unit, and realizedheritability methods. The heritability percentages for harvest index, grain yield, and plant weight were similar, and averaged between 50 and 65 precent across environments. Standard-unit and realized heritability percentages agreed closely and generally were lower than those computed via the variance-component method. Expected heritability percentages for harvest index calculated by using grain and plant yield data agreed almost exactly with actual values. Genotypic correlations were 0.88 between grain yield and plant weight, 0.42 between harvest index and grain yield, and –0.07 between harvest index and plant weight. Genotypic and phenotipic correlations were similar in magnitude. Theoretical and actual genotypic and phenotypic correlations of harvest index with grain yield and plant weight agreed closely. Genotypic correlations, computed via parent-offspring relationships, between harvest index and plant height, 100-seed weight, grain number, and heading date averaged –0.41, 0.43, 0.00, and –0.33 respectively.Indirect selection for grain yield through harvest index was 43 percent as efficient as direct selection, and a selection index that combined harvest index and grain yield was no more efficient than direct selection for yield. Harvest index had little value as a selection criterion for grain yield improvement when unrestricted selection was used. Indirect selection for grain yield through harvest index, however, would be expected to retain lines with a more favorable combination of yield, plant height and heading date than would unrestricted direct selection for yield.Journal Paper No. J-7914 of the Iowa Agriculture and Home Economic Experiment Station, Ames, Iowa 50010, Project No. 1752. 相似文献
18.
Tef is a staple cereal of Ethiopia in high demand by consumers. In order to cope up with this high consumer demand, productivity
per unit of land must increase through the development and use of high-yielding varieties. To this effect, the National Tef
Research Project has long been striving towards the development of high yielding varieties through direct selection from germplasm
and concentrating favourable alleles through hybridization and selection, despite the tedious crossing technique. The objective
of this study was to assess the degree of genetic variation in F2 populations of tef as a basis for improving grain yield. F2 populations from 12 crosses and their parents were grown at the Debre Zeit Agricultural Research Center, Ethiopia, and assessment
was made on eight traits on individual plant basis. Eleven of the 12 crosses showed substantial genetic variation for grain
yield and its components, indicating the potential for improvement through selection. Moreover, grain yield, plant weight
and yield related traits showed moderate to high heritability values (17–80%). In all the crosses, tiller number, panicle
weight, yield per panicle and panicle length showed significant (P ≤ 0.05) and positive association with grain yield. Considering the degree of genetic variation and heritability values, emphasis
should be given to selected crosses in an effort to developing high-yielding tef varieties. 相似文献
19.
Summary Sorghum [Sorghum bicolor (L.) Moench] backcross populations containing 3 to 50% wild germplasm were evaluated in south central India for grain yield and nine related traits. No individual BC0F2- to BC2F2-derived lines were high transgressive segregates for grain yield. Only 1.5% of all BC3F2- or BC4F2-derived lines were transgressive segragates, with 26% higher mean grain yield than their respective recurrent parents. The ten highest-yielding BC2F2- to BC4F2-derived lines per mating having parent CK60B yielded an average of 14% more than CK60B, which was, at the 5% level, a statistically significant difference. However, the increased yield was associated with increased plant height. The highest-yilding lines from RS/R/A2725 x virgatum and RS/R/A2725 x verticilliflorum were an average of 13.5% higher-yielding than RS/R/A2725 (a significant difference) and were equal in plant height. Selection increased BC2 mean grain yields by 6 to 27%. Population mean yield, mean yield of selected lines, and frequency of high-yielding lines were highest in the BC4.Journal paper no. 380, ICRISAT, Patancheru, India; Journal paper no. J-11114, Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa, USA. 相似文献
20.
Summary Three S1-recurrent selection programs (designated HG, HP, and HGP) for increasing protein yield of oat (Avena sativa L.) were conducted for five cycles of selection. The selection criteria in each program (line of descent) emphasized different components of protein yield; high grain yield in HG, both high protein concentration of the groats (caryopsis) and high grain yield in HP, and high protein yield per se in HGP. Heading date and height were restricted to no net change. The objectives of this study were to evaluate the agronomic performance of these three lines of descent and the correlated responses in agronomic traits due to selection. Thirty to sixty random S0-derived lines from each cycle and ten check lines were grown in hill-plot experiments at two locations in 1989. Grain yield increased in all three lines of descent; HG showed the greatest rate of gain followed by HGP and then HP (0.20, 0.10, and 0.07 Mg ha-1 per cycle, respectively). Test weight decreased in HGP by 2.6 kg m-3 per cycle and in HP by 4.0 kg m-3 per cycle, but remained constant in HG. Cycle 5 (C5) means for straw yield, height, and seed weight were not significantly different from the C0 means for any line of descent. Groat percent remained unchanged in HGP, increased from 70.1 to 71.7% in HG, and decreased from 69.9 to 67.6% in HP. Heading date decreased by 3 d in HG and HGP, but remained unchanged in HP. HG compares most favorably with commercial cultivars because of its high yield and acceptable agronomic traits, while HP tends to be low in test weight, seed weight, and groat percent.Abbreviations BM-
above ground biomass
- GP-
groat (caryopsis) percent, fraction of average seed weight that is groat rather than hulls
- GPC-
groat-protein concentration
- GPY-
groat-protein yield
- GTY-
groat yield
- GY-
grain yield
- HD-
heading date
- HG-
selection for protein yield through high grain yield
- HGP-
selection for protein yield per se
- HP-
selection for protein yield through high grain yield and high groat-protein concentration
- HT-
height
- PY-
protein yield
- SDWT-
seed weight
- SY-
straw yield
- TWT-
test weight 相似文献