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201.
Seventeen diverse clones of sugarcane (Saccharum spp.) (7 early, 6 mid season and 4 late) were planted in October 1991 and 1992 in flooded (FE) and non flooded (NFE) environments for evaluation of cane yield, commercial cane sugar (CCS), internode length, internode number, stalk length, stalk thickness (circumference), stalk number, sugar recovery, and stalk weight. Cane yield showed significant positive phenotypic correlation coefficient (PCC) with stalk number in FE (P ≤ 0.05) and NFE (P ≤ 0.01). Stalk length had a significant positive PCC with stalk weight in both environments, and with internode length in FE (P ≤ 0.05). Commercial cane sugar also expressed significant positive PCC with cane yield in both environments (P ≤ 0.01), but with stalk number only in NFE (P ≤ 0.05). Genotypic correlation coefficients were generally in the same direction as PCC but higher in magnitude. In both environments, stalk number and stalk weight had relatively high positive direct effects on cane yield. However, flooding tended to enhance the direct effect of stalk weight and diminish the direct effect of stalk number on cane yield. Only cane yield and sugar recovery had high direct effects on CCS. Selection for improvement of cane yield can be based on stalk number and stalk weight in both environments. High yielding clones can be further screened for more sugar recovery to improve CCS. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
202.
In a study of variation in 13 enzymes occurring in B. nana, unique and invariant phenotypes were found for five of these enzymes, when compared with a range of other wild and cultivated beets. In similar comparisons unique alleles were found in B. nana for two other enzyme loci. For the remaining six enzymes B. nana was found to have variation and alleles which were common to other forms of beet. It is concluded that reliable markers for B. nana exist, and that this species represents a source of novel genes for sugar beet breeding.  相似文献   
203.
Summary The objective was to study the genetic basis of bolting and stem length in sugar beet full-sibs, developed by a factorial mating design (N.C. design II). The extent to which the inheritance of these characters can be attributed to the additive and non-dominance variation was investigated. The genetic analysis consisted of three sets (4×10, 4×8, and 3×8) of progenies. Estimates of additive genetic variance (2 A) and variance due to dominance deviations with some fractions of epistatic variance (2 D) were obtained for both characters. Bolting had a relatively large proportion of total genetic variance accounted for by 2 A. In most cases, non-additive effects were also important in determining the type of gene action in bolting. Stem length showed similar genetic variation to bolting susceptibility. Bolting resistance seemed to be dominant to the bolting susceptibility in most cases. Narrow sense heritability estimated for bolting was generally very large (0.93 to 0.96), which suggests that early generation selection for bolting resistance in a sugar beet population would be successful.  相似文献   
204.
采用不同工艺条件测定蘑菇与黄豆芽混合汁中营养成分的含量。经测定得知,蘑菇:黄豆芽:水:1:2:3,利用内源酶水解24h,混合汁中水溶性含氮物、VC含量较高,利用内源酶或盐酸水解可显著提高还原糖浓度。  相似文献   
205.
Summary Central Asian apricot germplasm was used in hybridizations with California adapted apricots to increase Brix levels and improve fresh eating quality. Fruit from parental trees, the F1 hybrid and two backcross families were evaluated for fruit quality traits and analyzed by HPLC for specific sugar content. The F1 hybrid between Central Asian and California adapted apricots was intermediate to its parents in many of the evaluated characteristics and levels of specific sugars. When the F1 hybrid was backcrossed to California adapted apricots ‘Lorna’ and ‘Robada,’ the resulting hybrids were diverse in Brix, juice acidity, fruit size and profiles of specific sugars. Glucose: fructose ratios higher that 3.3 were encountered in fruit from five of the 22 analyzed seedlings, and fructose: sorbitol ratio ranged from 0.67 to 6.46. Brix and total sugar content correlated significantly with each other and with both sucrose and glucose. No significant correlations existed between sorbitol and any of the other analyzed sugars, nor with Brix or total sugars. The results demonstrated the extent of sugar profile modification possible in California adapted apricots after just two generations of breeding with Central Asian apricot germplasm.  相似文献   
206.
栎属4个树种秋冬叶色与生理变化的关系   总被引:2,自引:1,他引:2  
为了研究栎类树种秋冬转色期叶色变化的生理机制,以栎属4个树种——鲜红栎(Quercus coccinea)、纳塔栎(Quercus nuttallii)、沈氏栎(Quercus shumardi)、针栎(Quercus palustris)为试材,测定其秋冬转色期叶绿素、类胡萝卜素、花色素苷3种色素和可溶性糖、可溶性蛋白质含量变化。结果表明:叶绿素a、叶绿素b、总叶绿素含量均呈先快后慢的下降趋势;类胡萝卜素含量鲜红栎和沈氏栎呈现下降-上升-下降的趋势,其他2个树种呈平缓下降的趋势;花色素苷含量呈波动上升趋势;叶绿素a与叶绿素b的比值变化趋势前中期较为平缓,后期迅速下降;鲜红栎的可溶性糖含量为单峰曲线,其他3个树种呈双峰曲线,与花色素苷相关性不显著;蛋白质含量与花色素苷含量呈正相关。  相似文献   
207.
马凤鸣  高继国 《作物学报》1996,22(6):681-687
6个有代表性的甜菜品种在人工气候室的营养液培养试验表明,甜菜子叶期幼苗对NO3^-的吸收要经最初2h的适应阶段后才可均匀进行。均匀吸收后,观察到多倍体的吸收量〉2倍体,倍性相同品种中E型〉NE型〉NZ型〉Z型的初步结果。不同类型品种间NO3^-吸收的表观米氏常数(Km,app)、最大吸收速率(Im)有明显差异,除多倍体NZ型品种甜研301的Km,app较低而Im较高外,其余品种的Km,app和Im  相似文献   
208.
低温层积过程中圆齿野鸦椿种子的生理生化变化   总被引:2,自引:0,他引:2  
通过对不同层积时间圆齿野鸦椿种子萌发及其生理生化变化情况的研究,得出种皮对圆齿野鸦椿种子萌发具有很强的机械障碍,仅通过低温层积不能完全解除种皮的机械障碍.低温层积配合60℃温水浸种能够有效解除休眠.同时通过实验发现,当采取播前温水处理打破种皮机械障碍时,以低温层积90~120 d为宜,层积时间过长会导致萌发率降低.通过实验,对低温层积不同时间的圆齿野鸦椿种子生理生化变化情况进行测定,结果表明:随着层积时间增加,可溶性糖含量与G-6-PDH和6-PGDH联合酶活性波动上升,而淀粉含量波动下降.说明种子内含物质相互转化,逐步解除休眠,同时种子呼吸代谢中戊糖磷酸途径所占比重上升.POD活性先逐渐上升,在120 d后活性下降,笔者认为这可能是导致层积120 d后种子萌发率降低的主要原因.  相似文献   
209.
Summary Sugar beet is a relatively young crop, which supposedly has a narrow genetic base. Natural variation occurring in primitive beet varieties and in wild Beta species has been used for breeding sugar beet. This paper reviews information on desirable characteristics in Beta germplasm and the attempts made for the introgression of such characters into commercial breeding material. After an introduction on the availability of germplasm and the possibilities of hybridisation, attention is focussed on the mating system (especially male sterility), on morphological and physiological characteristics, including yield and sugar content, and on resistances to diseases and pests.  相似文献   
210.
D. M. Hogarth 《Euphytica》1980,29(3):737-746
Summary The diallel cross was found to be an unsuitable design for quantitative genetic analyses with sugar cane.Accidental selfing caused substantial inbreeding depression for most characters. Consequently, analysis of a diallel cross without regard to the effect of accidental selfing would be subject to bias, if accidental selfing were common. A selfing model proposed by Dudley (1963) was extended to include differential selfing, and was tested in an experiment in which the percentage of selfing in each cross was estimated visually.Variance components had large standard errors, which prevented firm conclusions from being drawn, but selfing appeared to cause substantial bias in the estimates. Estimates of genetic variance components from a p(p-1) diallel set, using the extended selfing model, were compared with estimates obtained from the standard analyses in which reciprocal or maternal effects should account for the effect of selfing. The estimates were comparable, but the standard analyses were simpler and produced estimates with lower standard errors.When the effects of selfing were minimized, general combining ability (g.c.a.) effects appeared to be much more important than specific combining ability (s.c.a.) effects for most characters.  相似文献   
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