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[目的]研究以玉林为代表桂东南地区杂交水稻理想株型的形态特征并量化其形态指标,为当地水稻育种和水稻株型改良提供理论依据.[方法]以桂东南地区15个杂交水稻品种为材料,观察记载其生育期、农艺性状及产量表现,综合分析各形态指标与产量之间的关系,初步确定桂东南地区水稻理想株型主要性状的量化指标.[结果]15个杂交水稻品种生育期介于113~124 d,株高为96~122 cm,剑叶长和宽分别为28.4~42.3cm和1.3~1.9cm,穗长为22.2~27.4cm,有效穗数为229.5万~304.5万穗/ha,每穗粒数130~198粒,结实率均超过80.0%,千粒重均在20.0g以上,产量为7762.5~8887.5 kg/ha.相关性分析结果表明,生育期、株高、穗长、每穗粒数、结实率和千粒重均与产量呈正相关,其中生育期和千粒重与产量的正相关达极显著水平(P<0.01,下同);剑叶长、剑叶宽和有效穗数与产量呈负相关,其中有效穗数与产量的负相关达极显著水平.通径分析结果表明,生育期、剑叶长、穗长、结实率和千粒重5个指标对产量的直接作用系数均为正值,其中生育期的正直接作用最大(0.60);株高、剑叶宽、有效穗数和每穗粒数4个指标对产量的直接作用系数为负值,以株高的负直接作用最大(-0.40).[结论]桂东南地区杂交水稻理想株型形态的量化指标为:生育期124 d左右,株高114~122 cm,剑叶长29.0~37.0 cm,叶宽1.3~1.5cm,穗长26.0~27.0 cm,有效穗数225.0万穗/ha左右,每穗粒数140~160粒,结实率85.0%~89.0%,千粒重约29.0g. 相似文献
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Summary Four six-rowed uniculm lines of spring barley were grown in two yield trials at different sowing densities. One trial was grown on light sandy soil in 1990. The second trial was grown on clay soil in 1991 and included the two-rowed, tillering cultivar Golf. In the trial on sandy soil, the grain yield of the uniculm lines approached that of Golf grown in an adjacent trial, but in 1991 when the growing conditions were more favourable, Golf yielded significantly more than the uniculm lines. Uniculm lines apparently perform relatively better under marginal growing conditions than in high yielding environments.The uniculm lines do not conform to the ideotype proposed for wheat by Donald (1968) but the results show that a drastic change in plant type need not to imply a large drop in grain yield. 相似文献
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Summary A knowledge of the biological and functional relationships among traits would be of benefit to plant breeders in the choice of traits to use for increasing efficiency of selection in a breeding program. Principal factor analysis was used to identify biological and functional relationships among dry bean (Phaseolus vulgaris L.) traits in segregating populations of a phenotypic recurrent selection program designed to introduce upright architecture into medium-sized dry bean.Two biological interpretations were assigned to factors extracted in the analysis of four seed/pod traits. The first was a size factor, loaded with seed weight and pod width, and the second a number factor, which was loaded with number of seeds per pod and pod length. Similarly, three factors were extracted from the analysis of fifteen architectural traits. The first factor was interpreted as an elongation factor, and was loaded with internode length measurements, while the second factor was interpreted as a structural factor, and was further divided into two subclasses namely, sturdiness factor and profile factor. The sturdiness factor comprised hypocotyl diameter and hypocotyl length, while the profile factor comprised branch angle and number of basal branches. The third factor which was called a reproductive factor was loaded with pod distribution traits and the number and location of nodes on which pods were borne. 相似文献
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Low tillering lines of spring wheat ( Triticum aestivum L.), were evaluated for their ability to conform to a high yielding ideotype in a dryland environment with spring drought. The ideotype was based on a concept of saving water as a result of reduced canopy development before anthesis; this should improve moisture supply for grain filling, thus reducing the effect of drought.
Five genotypes were compared under two nitrogen (N) levels, and at similar plant densities, at a site in the drier wheatbelt area of southwestern Australia. The genotypes formed three tillering groups based on the maximum number of culms produced: a free tillering group (G1), which included the standard cultivar Gamenya , with 4.3 culms per plant, an intermediate tillering group (G2) with 3.2 culms per plant, and a low ullenng group (G3) with 2.4 culms per plant.
Leaf area indices (LAI) were strongly affected by N but this was not reflected in total water use and biological yield. However, water was prematurely depleted before anthesis as a result of rapid early leaf development in response to N, and this reduced grain yield. Reduced tillering produced no significant increase in gram yield over the controls; fewer tillers per plant failed to suppress LAI development and water-use before anthesis because of a compensating increase in LAI; this resulted from a greater leaf size in the reduced tillering lines. Hence the low tillering lines did not fully conform to the requirements of the ideotype.
The development of low tillering lines is seen as a significant advance towards the ideotype; with yields comparable to commercial cultivars grown in the region, their performance indicates a potential for substantially higher yields if compensating increases in leaf development can be suppressed. 相似文献
Five genotypes were compared under two nitrogen (N) levels, and at similar plant densities, at a site in the drier wheatbelt area of southwestern Australia. The genotypes formed three tillering groups based on the maximum number of culms produced: a free tillering group (G1), which included the standard cultivar Gamenya , with 4.3 culms per plant, an intermediate tillering group (G2) with 3.2 culms per plant, and a low ullenng group (G3) with 2.4 culms per plant.
Leaf area indices (LAI) were strongly affected by N but this was not reflected in total water use and biological yield. However, water was prematurely depleted before anthesis as a result of rapid early leaf development in response to N, and this reduced grain yield. Reduced tillering produced no significant increase in gram yield over the controls; fewer tillers per plant failed to suppress LAI development and water-use before anthesis because of a compensating increase in LAI; this resulted from a greater leaf size in the reduced tillering lines. Hence the low tillering lines did not fully conform to the requirements of the ideotype.
The development of low tillering lines is seen as a significant advance towards the ideotype; with yields comparable to commercial cultivars grown in the region, their performance indicates a potential for substantially higher yields if compensating increases in leaf development can be suppressed. 相似文献
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水稻超高产育种的可能途径 总被引：2，自引：0，他引：2
回顾水稻超高产育种的背景和现状,对超高产育种的基础、目标、途径、进展及存在问题等进行了综述。展望超高产育种未来发展方向,必须大力加强高新技术的发展和多学科之间的合作,共同攻克难关,以实现我国水稻育种的第三次突破。 相似文献
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Methods were developed to quantify variation in the fruit, nut and kernel traits using the fruits from four trees of Irvingia gabonensis, an indigenous fruit tree of west and central Africa. The measurement of 18 characteristics of 16–32 fruits per tree identified significant variation in fruit, nut and kernel size and weight, and flesh depth. Differences were also identified in shell weight and brittleness, fruit taste, fibrosity and flesh colour. Relationships between fruit size and weight with nut and kernel size and weight were found to be very weak, indicating that it is not possible to accurately predict the traits of the commercially-important kernel from fruit traits. Seven key qualitative traits are recommended for future assessments of the levels of genetic variation in fruits and kernels. These traits describe ideotypes for fresh fruit and kernel production.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
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Summary Plant growth habit (type) plays a major determining role in the acceptance of a dry bean cultivar by commercial growers. Under the threat of wet fall conditions in the midwestern U.S., growers show a preference for upright plant types-I and II over the more prostrate type-III growth habit of commercial pinto cultivars. The prostrate habit creates considerably more risk of harvest losses and potential of white mold (Sclerotinia sclerotiorum) development during a wet growing season.The breeding strategy being utilized to develop better adapted pinto bean cultivars for the humid midwest is based on the concept of ideotype breeding which has been successfully applied to small seeded navy and black beans. A system of phenotypic recurrent selection using S1 selection is being followed in order to recombine desirable traits from two diverse germplasm pools. One germplasm pool possesses the desirable architectural plant form and disease resistance traits of the small-seeded types while the medium-seeded germplasm source possesses the desirable seed size, shape and color characteristics of the pinto class. Since a repulsion phase linkage appears to exist between type-II architecture (architype) and medium seed size (40 g/100 seeds), recurrent selection is shown to be the most effective procedure for breaking up undesirable linkage groups and for increasing the frequency of desirable genes, thus enhancing the chance for the desirable genetic recombinations to occur.Journal Article No. 11667 of the Michigan Agricultural Experiment Station. 相似文献