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31.
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   
32.
葡萄结果母枝粗度与新梢结实力的关系   总被引:1,自引:0,他引:1  
研究了11个葡萄品种结果母枝粗度与新梢结实力的关系,结果表明,不同葡萄品种获得理想的新梢结实力,其结果母枝须有一适宜的粗度范围;结果母枝粗度与结果枝率、结果枝结果系数、新梢结果系数之间呈二次多项式回归关系;不同葡萄品种冬季修剪时结果母枝的选留应以不同粗度结果母枝的结实力为依据。  相似文献   
33.
Summary Varying degrees of resistance to cane spot were recorded among red raspberries in two cultivar trials and in 15 segregating families. The inheritance of resistance was studied, and the effect of gene H which determines the presence of cane hairs was assessed in eight of the families. The 0 to 5 scale used to record disease incidence was found to approximate to a logarithmic scale for the range of 0 to 93 cane spots per cane. Gene H and h phenotypes averaged scores of 3.05 and 2.42 respectively, but other genes independent of these had more influence on resistance. The latter genes appeared to be largely dominant. The possibility is discussed that one of them was a major gene with a large effect, but the evidence was equivocal in the absence of discontinuity in the expression of resistance. Resistance to yellow rust was studied in five of the families and was highly correlated with resistance to cane spot. Gene H had more influence on this disease, the mean counts of telia per unit leaf area for H and h segregates being 17.1 and 4.1 respectively.  相似文献   
34.
用纸层析法和比色法分离测定了几种沙生植物叶片可溶性糖和多糖含量、日变化及失水50%时的多糖含量.结果表明:沙冬青、白刺、霸王、籽高和猫头刺白天可溶性糖最高含量分别为16%、8%、14%、11%,5%.前三种植物多糖最高含量分别为5.6%、7.6%、7.5%,其日进程与可溶性糖存在一种互补关系;叶片失水50%时,白刺多糖增加1.31倍,霸王1.21倍,沙冬青0.44倍.这表明:某些沙生植物主要靠增加可溶性糖含量以提高渗透调节能力适应干旱;有的则以增加多糖含量以增强胶体保水能力忍耐干旱;另一些植物则兼而有之.  相似文献   
35.
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   
36.
以设施栽培的艳光油桃为试材,研究了设施栽培条件下,喷施KH2PO4处理对油桃果实中糖积累和蔗糖代谢相关酶活性的影响。结果表明,幼果期喷施KH2PO4处理,果实葡萄糖和果糖含量明显增加,蔗糖含量没有明显变化,成熟期三种糖含量与对照均无明显差异;果实着色前KH2PO4处理显著增加了果实中蔗糖含量,但对葡萄糖和果糖含量无明显影响。幼果期和着色前喷施KH2PO4均显著提高了果实中蔗糖代谢酶活性。说明KH2PO4处理是通过全面提高果实中蔗糖代谢酶活性,起到提高库强作用,从而增加果实含糖量。  相似文献   
37.
黄藤(Daemonorops margaritae),是我国热带和南亚热带森林中的主要伴生植物,是我国的优良商品棕榈藤种,为中国特有种(许煌灿等,1994a)。天然分布以海南岛为中心,延伸至23°30'N以南的广  相似文献   
38.
39.
The addition of sugar beet to soils as a source of C led to an increase in the availability of easily utilizable C (glucose), which in turn markedly increased numbers of soil bacteria and of the yeast Williopsis californica. Nitrification, P solubilization, urea hydrolysis (and the subsequent nitrification of liberated NH inf4 sup+ ) were stimulated by this amendment. The stimulation of nitrification may have been a result of increased heterotrophic nitrification. In contrast, the concentration of sulphate in So-amended soils declined following amendment, presumably as the result of enhanced S immobilization. Activity of the enzymes amylase, aryl sulphatase, invertase, phosphatase, dehydrogenase, and urease were all stimulated by the sugar beet amendment. These results suggest that sugar beet amendment could be used to increase the rate of release of plant-available ions from fertilizers such as insoluble phosphates. Problems may arise, however, from a subsequent increase in nitrification and reduced sulphate availability.  相似文献   
40.
分别采用30、50、70Gy3种等级的60Co射线对果蔗种芽进行辐射处理,使果蔗后期生长受到不同程度的影响,表现为植株变矮、茎变细、锤度降低、丛条数变少、生势变差,并随着辐射剂量的增加,影响程度随之加大。4个果蔗品种对60Co辐射敏感性不一,罗汉蔗>白玉蜜蔗>黑皮果蔗>温岭果蔗;从辐射后代中筛选出21个单系,平均入选率为9.86%,其中以温岭果蔗30Gy辐射处理的入选率最高,达25%。  相似文献   
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