首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 93 毫秒
1.
A. Marocco    L. Cattivell    G. Dtloou    C. Lorenzoni  A. M. Sianca 《Plant Breeding》1992,108(3):250-255
The effect of recurrent selection procedure for improving grain yield in autogamous cereals was evaluated in a six-rowed winter barley population. Gain from selection was estimated by field testing 90 random S2 lines from each of the C0, C1 and C2 populations. Response to selection for grain yield was 0.78 t/ha from C0 to C1 and 1.09 t/ha from C1 to C2. Broad-sense heritability and genotypic variance for grain yield remained high in all cycles which suggests further gain from additional selection cycles. Yield increase was due to a higher number of seeds/m2. Significant differences among mean values were observed for heading date (189 days in C0 and 182 days in C2), whereas no variation was seen for plant height and 1000-kernel weight. The proposed recurrent selection procedure appears effective to improve the population and to extract superior genotypes for varietal development.  相似文献   

2.
The consumption of products made from Tartary buckwheat (Fagopyrum tataricum (L.) Gaertn.) has increased in recent years in Japan. Increased consumer demand has led to recognition of the need for early varieties of this crop with high and stable yields. In order to accomplish this, more information is needed on the genetic mechanisms affecting earliness and yield. We conducted genetic analysis of 3 agronomic traits (days to flowering, plant height and total seed weight per plant) to segregate F2 and F3 populations derived from a cross between Tartary buckwheat cultivars ‘Hokuriku No. 4’ and ‘Ishisoba’. Broad-sense heritability estimates for days to flowering, plant height and total seed weight were 0.70, 0.62 and 0.75, respectively, in F3 population. Narrow-sense heritability for total seed weight (0.51) was highest, followed by heritability for days to flowering (0.37), with heritability for plant height (0.26) lowest. Later flowering was associated with increased plant height and higher yields. From the F4 generation, we identified twelve candidate plants with earlier maturity and reduced plant height compared to ‘Hokuriku No. 4’, but almost the same total seed weight. These results suggest that hybridization breeding using the single seed descent (SSD) method is an effective approach for improving agronomic characteristics of Tartary buckwheat.  相似文献   

3.
No information is available on the effects of different biomass yield environments on selection efficiency in switchgrass (Panicum virgatum L.) breeding improvement. This study was conducted to assess the effects of high- and low-biomass yield environments (HYE and LYE, respectively) on recurrent selection for general combining ability (RSGCA) in a lowland population of switchgrass (NL-94). The top 14 of 65 NL-94 C0 parent plants were selected based on biomass yield of half-sib (HS) progeny tested for one post-establishment year under HYE and LYE conditions. Nine of the 14 C0 parent plants were the same based on HS performance under HYE and LYE. Selected plants were intercrossed to produce NL-94 HYE and NL-94 LYE C1 populations. One hundred and twenty-five HS C1 progeny families (60 NL-94 HYE and 65 NL-94 LYE) were evaluated for biomass yield for 3 years (2002–2004) under HYE and LYE conditions. The HYE produced about 2.5 times higher biomass yields than the LYE in both C0 and C1 HS progeny tests. Estimated additive genetic variance and predicted gains from selection (ΔG) were high in the C1 populations indicating that RSGCA should achieve higher biomass yields. Mean biomass yields of C1 HS families originating from the LYE protocol were significantly higher than those of families originating from the HYE protocol in both HYE and LYE performance tests, suggesting greater selection response under LYE in the C0 population. The estimates of narrow-sense heritability ( ) and ΔG from the C1 populations indicate that positive response to selection for biomass yield is possible in subsequent cycles of selection under either HYE or LYE, with a possible small advantage for HYE.  相似文献   

4.
导入外源玉米C_4型NADP-ME基因对小麦光合效能的影响   总被引：1，自引：0，他引：1  
为研究玉米C_4型NADP-ME基因对小麦光合特性的影响,以T_3代转NADP-ME基因小麦株系10T(9)-1-1和10T(9)-225-4及其对照周麦23为试材,进行了分子特征鉴定、光合生理特性分析和单株产量性状调查,并对其作用机制进行了初步解析。结果表明,外源基因已整合到转基因小麦的基因组中,并能正确转录和翻译;与对照周麦23相比,两个转基因株系在4个测定时期旗叶NADP-ME酶活性均明显提高,而旗叶净光合速率(P_n)则明显下降;尤其在花后第7天,两个转基因株系的酶活性较对照分别提高1.33倍和1.13倍,P_n分别较对照下降17.26%和10.35%;千粒重和籽粒产量较对照均显著下降。与对照周麦23相比,转基因株系10T(9)-225-4利用强光和同化CO_2能力下降,光合效率下降;旗叶气孔张开率和气孔导度均显著下降;苹果酸含量降低了5.6%,丙酮酸含量则提高了17.1%;外施苹果酸可恢复其光合速率。以上研究结果表明,玉米C_4型NADP-ME基因的导入降低了小麦的光合特性,苹果酸含量降低引起的气孔导度下降可能是导致转基因小麦光合效能降低的原因。  相似文献   

5.
Summary The effect of a recurrent selection procedure was evaluated in a winter barley (Hordeum vulgare L.) population. Cycle zero (C0) was initiated by crossing six high yielding winter barley cultivars with the short straw cv Onice. The F1's were crossed according to a diallel scheme without reciprocals. A total of 750 S0 plants were derived and evaluated; 329 S0 plants were selected and their progenies (S1 lines) tested. Fifteen S1 lines were chosen and used as parents of cycle 1 (C1), by producing 105 F1 hybrids which simulated a random mating offspring. One hundred and three randomly chosen S1 lines belonging to C0, and 103 S1 lines belonging to C1, were evaluated at two locations.For grain yield a significant difference between cycles was observed. From C0 to C1 the grain yield increased with 307 g/m2. This increase was due to a higher number of seeds per m2. For plant height, heading date and 100-kernel weight no differences between cycles were observed.The positive results obtained in this study indicate the potential usefulness of recurrent selection for developing parents or lines superior for grain yield, with little change in other important agronomic traits.  相似文献   

6.
Development of multiple insect resistance in tropical maize represents a major effort of the maize breeding programme at CIMMYT. Resistance to the southwestern corn borer (SWCB) is polygenically controlled with primarily additive gene action. Our main objective was to identify quantitative trait loci (QTL) involved in resistance to SWCB. Other objectives were to detect QTL in the same population for plant height, female flowering, and the anthesis-silking interval (ASI). A population of 472 F2 individuals derived from a cross between the susceptible line Ki3 and the resistant inbred CML139, was restriction fragment length polymorphism (RFLP) genotyped using 110 maize probes. F3 families were rated for leaf-feeding damage after artificial infestation at one location in three consecutive years. Height and flowering were measured in protected trials in two locations. QTL analyses were conducted using joint composite interval mapping. Seven QTL on chromosomes 3, 5, 6, 8, and 9 explained 30% of the phenotypic variance (σ2p) for SWCB damage. Most QTL alleles conferring resistance were contributed from CML139. QTL showed dominance, partial dominance and additive gene action. Eleven QTL dispersed across the genome were determined to affect plant height and explained 43% of σ2p. Four of these were in close proximity to loci with qualitative effects on plant height. Thirteen QTL (50% of sigma;2p) were identified for days to female flowering and nine (30% of σ2p) for ASI. Our results, along with those from other mapping studies at CIMMYT, are allowing us to formulate marker-assisted selection schemes to complement the breeding efforts for such complex traits as borer resistance.  相似文献   

7.
Approaches are needed to broaden the genetic base and improve earliness and yield potential of large-seeded beans under sustainable cropping systems. The objective of this research was to develop adapted dwarf bean populations having a commercial seed quality and yield suitable for the production in the South of Europe. The original base populations were produced from crosses between genotypes within each Mesoamerica, Nueva Granada and Peru races, and between Peru and Nueva Granada, and Mesoamerica and Nueva Granada races. Visual mass selection for plant performance was practised in the F2 and F3 generations. In the F4 and F5, single plants were harvested under two cropping systems (sole cropping and intercropping with maize). From F4, selection was based on precocity, combined with seed yield and seed commercial type. The F4:7 selected lines from each original population were compared with their parents and five checks at four environments and two cropping systems. Differences among environments, populations, parents and checks were observed for all traits. Under intercropping with maize, there was a 50% reduction in seed yield. Yield of parents and checks belonging to Andean South American races, intraracial (Nueva Granada × Nueva Granada) and interracial (Nueva Granada × Peru) populations, was higher than that of those of Middle American origin. Intraracial crosses within large-seeded Andean South American (Peru race) and Middle American gene pools (Mesoamerica race) did not produce lines yielding more than the highest yielding parent. Only two large-seeded lines selected from crosses between small- and large-seeded gene pools out-yielded the best parent and check cultivar.  相似文献   

8.
The PTM3 (MADS-box) gene characterized from flower of Aspen was ectopically expressed in cotton and was found to result in desirable agronomic traits. Among several transgenic lines, the PTM3 cotton event-10 was found to flower significantly earlier than the control and yield better [Ramachandran et al. (2011)]. We report our findings on performance based on greenhouse evaluation and inheritance of PTM3 cotton event-10. The T1 progeny of event-10 were grown in pots under RBD design. The progeny were confirmed by kanamycin imbibition test, PCR, and GUS assay which showed the segregation of transgene at about 3:1 ratio. GUS assay was performed with pollen from all transgenic plants; plants that expressed gus in all pollen versus those that showed segregation for expression were found to be at a ratio of 1:2. Similar to observations made in the T0 generation of event-10, the agronomic evaluation of T1 progeny exhibited, on an average, earliness of 13 days in flowering, 13.5 days in crop maturity, and 22% of yield enhancement. The T2 progeny of homozygous lines were grown on field soil in the greenhouse under strip trial design to see the effect as observed from potted plants of T1 progeny. Inheritance of transgene cassette to T2 progeny was confirmed by the same tests used to analyze T1 progeny. As exhibited by T0 and T1 progenies, the T2 progeny also showed earliness of 8 days in flowering, 12 days in crop maturity, and 17% of yield enhancement. The data generated from the progeny over two generations confirms that the PTM3 cotton event-10 is superior in agronomic characters as compared to non-transgenic cotton and is of interest for breeding shorter duration varieties with improved yield.  相似文献   

9.
Divergent Selection for Heading Date in Barley   总被引：1，自引：0，他引：1  
Divergent selection for heading time was performed in two F2 barley population. Five populations were obtained for each cross: F5 SSD (unselected control), 3E and 3L (from three cycles of selection for earliness or lateness), 2E1L and ZL1E (from two cycles of direct and one of reverse selection). These populations, together with corresponding parents and F2 generations, were evaluated over two years. The response to selection was 5.6 and 6.5 days inane direction (earlier heading) and 7.7 and 6.7 clays in the other direction (later heading) in the two crosses, respectively. 3E and 3L populations were highly transgressive as compared to their parents. A sizeable amount of genetic variability was still present after two cycles of selection. Heading was probably controlled by a polygenic system with prevailing additive effects and alleles for earliness and earliness somewhat equally distributed in the parents. Selection fur heading time led to significant changes in plant height, yield and kernel weight. Early progenies were higher yielding than lace ones.  相似文献   

10.
R. N. Kulkarni 《Euphytica》1994,78(1-2):103-107
Summary Phenotypic recurrent selection was carried out for oil content in East Indian lemongrass, Cymbopogon flexuosus (Steud) Wats. In each cycle, the top 5% of plants for oil content were selected. Their ramets were used for the establishment of replicated polycross blocks in isolation. Realized gains from selection were determined by evaluating the populations and the best clones from each population in separate two-year replicated trials. Three cycles of recurrent selection increased oil content by 32% per cycle at the population level. Realized gains from selection were slightly smaller or similar to predicted gains. Mean realized heritability for oil content was 0.56. At the clonal level, the best C1 and the best C2 clones had, respectively, a 22% and 73% higher oil content than the best clone from the base population (C0). Selection for oil content did not adversely affect leaf yield, dry matter content or citral content in oil. Probable reasons for the high response to selection are mentioned.  相似文献   

11.
This study was conducted to evaluate the growth characteristics and fatty acid composition among 15 kenaf mutants derived from the kenaf germplasm C14 and 15 kenaf accessions originating from Russia, India, China, Iran, and Italy. The overall growth performance (plant height, stem diameter, flowering date, leaf, and flower size) of the stem color mutant lines derived from C14 are similar to those of the original variety. However, the flower color mutant lines derived from C14 showed flowering to occur 10 days later when compared with the original variety and showed smaller leaf sizes than the original variety. Late-ripened kenaf accessions (Jinju, Auxu, and Jnagdae) can yield more bio-mass compared with early or medium-maturing germplasm. The late maturity kenaf (Auxu, Jinju, and Jangdae) has a higher oil percentage than the early maturity germplasm. Linoleic, oleic, and palmitic acids were the predominant fatty acids in all kenaf seeds. The stem color mutant lines significantly surpassed the parental means of all saturated fatty acids. In addition, the flower color mutant lines showed broad ranges of variation in oleic acid. The 15 accessions showed a wide range of fatty acid compositions, spanning from 29.75 to 38.30% saturated fatty acids and 61.70 to 70.24% total unsaturated fatty acids, and the late maturity kenaf has a higher linoleic acid percentage than the early maturity germplasm. The flowering period was highly positively (P ≤ 0.01) correlated with the plant height, stem diameter, oil percent, and linolenic acid (C18:3), and it was significantly negatively (P ≤ 0.01) correlated with stearic acid (C18:0). These results will provide valuable information to assist the parental selection of kenaf breeding.  相似文献   

12.
Due to the short growing season in the high northern latitudes, the development of early maturing spring wheat (Triticum aestivum L.) cultivars is important to avoid frost damage which can lower production and quality. We investigated earliness of flowering and maturity, and some associated agronomic traits, using a set of randomly selected high northern latitude adapted spring wheat cultivars (differing in maturity) and their F1 and F2 crosses made in a one-way diallel mating design. The parents, and their F1 and F2 crosses were evaluated under field conditions over 2 years. Anthesis and maturity times were controlled by both vernalization response and earliness per se genes, mainly acting additively. Non-additive genetic effects were more important in controlling grain fill duration, grain yield and plant height. Additive × additive epistatic effects were detected for all traits studied except time to anthesis. Segregation analyses of the F2 populations for time to anthesis indicated the presence of different vernalization response genes. Molecular genetic analyses revealed the presence of Vrn-A1 and Vrn-B1 genes in the parental cultivars. Narrow-sense heritability was medium to high (60–86%) for anthesis and maturity times but low to medium (13–55%) for grain fill duration, plant height and grain yield. Selection for early flowering/maturity in early segregating generations would be expected to result in genetic improvement towards earliness in high latitude spring wheats. Incorporation of the vernalization responsive gene Vrn-B1 in combination with vernalization non-responsive gene Vrn-A1 into spring wheats would aid in the development of early maturing cultivars with high grain yield potential for the high latitude wheat growing regions of the northern hemisphere.  相似文献   

13.
Summary Experiments were conducted during the growing seasons of 1975 and 1976 to determine changes in morphological and physiological traits associated with recurrent selection for grain yield in maize (Zea mays L.). Four variety hybrids, BSSS(R)CO x BSCB1(R)CO, BSSS(R)C7 x BSCB1(R)C7 [from a reciprocal recurrent selection program involving Iowa Stiff Stalk Synthetic (BSSS) and Iowa Corn Borer Synthetic #1 (BSCB1)], BS12CO x B14A, and BS12C6 x B14A [from a half-sib selection program involving the open-pollinated variety Alph (BS12) and the inbred tester B14A] were grown at 59 300 and 98 800 plants/ha near Ames, Iowa We obtained data on CO2-exchange rate (an estimate of photosynthetic rate), grain yield, grain-yield components, flowering dates, maturity traits, light interception and use, shelling percentage, harvest index, and various other plant traits.CO2-exchange rate did not change appreciably with recurrent selection for yield. Grain yield per hectare and per plant were larger for the improved than unimproved hybrids. Grain-yield components did not change significantly with recurrent selection. Kernel weight of BSSS(R)C7 x BSCB1 (R)C7, however, was larger than that of BSSS(R)C0 x BSCB1(R)C0. Pollen-shed-to-silking interval was shorter for the improved than the unimproved hybrids, and grain-filling duration was longer in C7 x C7 than in C0 x C0 of the reciprocal recurrent selection program. Furthermore, improved hybrids were characterized by smaller tassels and more upright canopies. Usually, plant traits and leaf-area-related traits were similar for all hybiids.Although dry-matter productivity was similar for all hybrids, those that were improved by recurrent selection produced more grain per unit leaf area and per unit light interception. Also, BS12C6 x B14A was characterized by a higher harvest index than BS12CO x B14A.We concluded that the source (i.e., photosynthetic capacity) was not limiting grain yield in BSSS(R) x BSCB1(R) and BS12. Increased grain yields that resulted from recurrent selection were consequences of longer grain-filling duration for BSSS(R) x BSCB1(R) and increased translocation of photosynthate from source to sink for both BSSS(R) x BSCB1(R) and BS12.Journal Paper J-8953 of the Iowa Agriculture and Home Economics Exp. Stn., Ames, Iowa. Project No. 2152.  相似文献   

14.
Perspectives of molecular marker assisted breeding for earliness in tomato   总被引：2，自引：0，他引：2  
In a tomato (Lycopersicon esculentum) breeding programme aimed at earliness, a breeding line, designated IVT-KT1, was developed by several rounds of crossing and selection. Among its ancestors were the two wild relatives L. pimpinellifolium and L. parviflorum. The breeding line flowered and set fruit one to four weeks earlier than old and modern cultivars. To identify QTLs for earliness, an F2 population was obtained by crossing IVT-KT1 with the late true breeding cultivar Premier. In winter and early spring, 690 plants of this F2 population were evaluated for earliness of which 292 were selected for RFLP analysis. Only limited parts of the genomes of IVT-KT1 and Premier were polymorphic and these polymorphisms were likely due to introgression from the ancestor wild species. By using the interval mapping method on the combined data of the greenhouse evaluations and RFLP analyses, three loci were identified that were associated with earliness. One was mainly associated with flowering time, another with fruitset time and a third one with ripening time. Two of these loci were also associated with fruit weight. F3 progenies selected for earliness on the basis of the QTL-data did confirm the F2 results. Two major earliness genes explained a difference in earliness of more than three weeks. The association with reduced fruit weight seemed to be due to pleiotropic effects rather than to linked genes. Consequently, the gain in earliness will cause a reduction in fruit weight that may not be acceptable for breeding applications.  相似文献   

15.
Five cycles of phenotypic recurrent selection for increased essential oil content were carried out in East Indian lemongrass, Cymbopogon flexuosus. In each cycle, the top 5% of plants for essential oil content were selected and their ramets were planted in isolated polycross blocks to produce the seed of the next cycle. Response to selection for essential oil content and its effect on three unselected traits, leaf yield, dry matter content in leaves and citral content in the essential oil, were determined by evaluating C0‐C5 populations in a replicated trial. Genetic variation, heritability estimates and intertrait correlations for essential oil content, leaf yield, leaf width, tiller number and citral content in the essential oil in C4 were determined, by evaluating 40 clones and their half‐sib progenies produced from 40 randomly selected C4 plants, in a replicated experiment. These were compared with those determined in C0 earlier. The mean essential oil content increased from 0.66% in C0 to 1.67% in C5 (i.e. by about 31% per cycle over C0). Selection for essential oil content did not affect leaf yield and its effect on dry matter content in leaves was marginal. The first three cycles of selection for essential oil content did not affect citral content in the oil but two further cycles significantly decreased citral content. Heritabilities and intertrait correlations between all traits studied, except citral content and essential oil content, were similar to those found in C0.  相似文献   

16.
To determine the effects of ethephon [(2‐chloroethyl) phosphonic acid] on yield and yield components of rainfed barley in arid (150 mm rainfall) and semiarid (346 mm) regions, the present study was conducted during the growing seasons of 1999–2001. Ethephon was applied at the tillering, stem elongation and flowering stages. Acomparison of the effect of ethephon on rainfed and irrigated barley performed at the semiarid location in the following season confirmed the results. Ethephon decreased grain yield when sprayed at tillering and stem elongation compared with the later flowering stage for both the arid and semiarid locations. All arid‐location barley plants had lower grain yields than the semiarid‐location plants. There was a reduction in spikes m?2 in the tillering and stem elongation stage sprayings compared to the control for both locations. In the semiarid and arid locations no difference in earliness (50 % heading) was observed between spraying times but ethephon always delayed heading. All arid‐location plants were earlier than semiarid‐location plants. However, when ethephon was used with supplementary irrigation it was found to increase grain yield, spikes m?2 and earliness.  相似文献   

17.
Choosing germplasm based on elite and diverse genetic sources is essential for the genetic improvement of maize (Zea mays L.) hybrids. The objectives of this research were to evaluate the agronomic and economic potential of maize population and single-cross hybrids and whether significant maternal (ME) and reciprocal effects (RE) reside in elite population hybrids for seed production purposes. Seven elite maize populations currently under recurrent selection at North Dakota State University (NDSU) [NDSCD(M-S)C11, NDSAB(MER-FS)C14, BS21(R)C7, BS22(R)C7, LEAMING(S)C4, CGL(S1-S2)C5 and CGSS(S1-S2)C5] were crossed in a diallel mating design to form 42 population hybrids, including their reciprocals. The 42 population hybrids with eight single-cross hybrids were evaluated at six U.S. North Central locations in 2005. Data collected across locations indicated that differences across genotypes were significant (P ≤ 0.05) for all traits observed, except for grain yield ear components. General combining ability (GCA) effects were on average larger than specific combining ability (SCA) effects. ME and RE were not significant for all traits, except for ear height. The large grain yield differences between macro-environments were reflected in the ranking of genotypes, with BS21(R)C7 × BS22(R)C7 being the top performer in eastern environments and CGSS(S1-S2)C5 × NDSAB(MER-FS)C14 being the top one across western environments where drought is the major limitation. The increased ethanol production and demand from maize make test weight (and grain quality), earliness, lodging resistance, and drought tolerance as important as grain yield for maintaining a sustainable maize-ethanol relationship. Part of the thesis submitted by McDonald B. Jumbo in partial fulfillment of the requirements for a MS degree at North Dakota State University.  相似文献   

18.
Summary The dates of flowering of six pea cultivars and their F1 and F2 generations grown under a moderate level of top-yellows virus infection were analysed by both Griffing's and Jinks' methods to assess the stability of the polygenic control of flowering period. Flowering period was shown to be under the control of an additive system with dominance for the late flowering characteristic. Some gene interaction was indicated in both analyses, mainly between the later-flowering cultivars, although tests for apparent over-dominance were insignificant. It was considered that the degree of virus infection within the experiment had little, if any, effect upon flowering times and that selections for flowering date in these circumstances should be almost as reliable as those made in a disease-free environment.Slightly increased earliness over the early parent was evident in five F2 progenies and it appears possible to make further slight gains in earliness by selection in the present material.  相似文献   

19.
Bahy R.  Bakheit 《Plant Breeding》1989,103(4):278-285
Modified mass and family selection for seed yield production of berseem clover (Trifolium alexandrinum L.) c.v. ‘Fahl’ were applied for two generations. Two hundred plants (5 % intensity of selection) were selected for seed yield in the first season, 1985/86. In the second season, 1986/87, selection between and within half-sib families was practiced. In addition, equal parts of seeds from each of the 200 selected plants were bulked to form the C1 modified mass selection; after establishing, the same procedure was adopted to form the C2 generation. The cycles 1 and 2 of half-sib families and modified mass selection along with the base population family were evaluated for forage and seed yields. The realized gains from modified mass selection were 6.03 and 9.51 % for fresh forage yield, 5.57 and 10.86 % for protein yield and 13.23 and 16.19 % for seed yield in cycles 1 and 2, respectively, over the base population. The realized gain from family selection in cycle 2 as a percentage of the base population mean amounted to 11.32, 13.35, 17.47 and 3.15% for forage, protein, and seed yield and seed index, respectively. The broad sense heritability, as estimated from the variance components was 89.63, 63.03, and 76.67 % for dry forage, seed yield and seed index, respectively. Although, all these five traits (fresh, dry, protein, and seed yield and seed index) had positive correlation with each other, weak correlations were found between seed yield and forage yields. Furthermore, close associations were found among forage yield traits.  相似文献   

20.
Summary Early testing was evaluated for efficiency as a procedure for selecting among lines for yield (total and marketable fruit number), earliness and fruit quality (shape, color and seedcell size) in 24 sets of lines developed at random from a pickling cucumber (Cucumis sativus L.) population. The advantage of early testing was calculated using the regression of S6 on S1 performance. The amount of effort required in worker-hours and the theoretical gain from selection were also considered in estimating the advantage of early testing. Early testing for specific combining ability and for general combining ability was up to 2.05 times as efficient as late testing for total yield, and up to 2.29 times as efficient as late testing for earliness. Early testing was not efficient for selection for the fruit quality traits measured, nor for inbred performance per se.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号