Die Wurzelentwicklung von Zuckerrübenpflanzen auf einem Sandlöß-Standort und ihre Bedeutung für die Stickstoffernährung

Root development of sugar beet plants on a sandy loess site with regard to nitrogen nutrition.
Root development of sugar beet plants in a sandy loess soil (Haplic Phaeozem) was observed from the early seedling stage up to harvest by measuring at first the greatest vertical and lateral extension of the root systems of single plants and later the rooting density of the whole plant stands (auger method, profile wall method).
During the seedling stage not only the subsoil, but also large parts of the topsoil between the plants remained unoccupied by the root systems. In this phase the greatest lateral extension of single roots reaches nearly the length of the greatest leaf of the plant. With the closure of the canopy the rooting density in the topsoil accounts to 1–2 cm cm⁻³.
In summer roots penetrate to a depth of 100–150 cm with rooting densities of 0.1 to 1 cm - cm⁻³. Thus, the plants gain not only access to water reserves, but sometimes meet remarkable amounts of nitrate which under the relatively dry conditions of the region tends to accumulate in 60–120 cm depth and – when taken up by the beet plants in the late stage of growth – affects crop quality negatively.     

笃斯越桔硬枝扦插繁殖技术研究

采用笃斯越桔硬枝扦插,用生根剂处理插穗,并在不同的基质上进行扦插试验,结果表明:笃斯越桔硬枝扦插用河沙作为基质最好,生根剂ABT处理的插穗生根率最高。     

糖和氮对山楂组织培养新梢生根的影响

采用敞口山楂组培新梢研究糖和无机氮源对不定根形成的影响,含有高水平蔗糖的培养基比低水平蔗糖的培养基新梢生根率高。新梢对糖的这种反应与糖代谢和物理渗透都有关,用甘露醇作为渗透代替剂在低浓度蔗糖存在下无作用,当蔗糖浓度达到一定程度时(86.64mmol·1~(-1))能影响新梢的生根率。在培养基中分别加入NO_3~(-)-N或NH_4~(+)-N作为唯一氮源,或是在MS培养基中加入NO_3~-/NH_4~+比率为标准的混合氮源,在测试范围(0～120mmol·1~(-1))内均降低新梢的生根率,三者对生根的抑制作用大小顺序依次为NH_4~+>NO_3~(-)-NH_4~(+)-N>NO_3~(-)-N.NO_3~-/NH_4~+的比率影响生根。NO_3~-/NH_4~+比率与生根之间呈直线正相关。糖/氮比值高有利于生根。插穗中碳、氮的绝对量及碳/氮比率可作为山楂新梢生根的指标。     

富贵竹室内加工技术研究

 设杀菌剂瑞毒霉锰锌、营养液爱多收和促根剂吲哚丁酸不同浓度9个处理组合, 研究其对富贵竹去叶植株修口、顶侧芽生长及生根的影响。结果表明, 瑞毒霉锰锌3水平间修口效果、爱多收3水平间顶侧芽生长、吲哚丁酸3水平间根系生长的差异均极显著; 最佳处理组合, 小竹为0. 8 g/L^-1瑞毒霉锰锌+ 0. 15 mL/L^-1爱多收+ 30 mg/L^-1吲哚丁酸, 大竹为0. 8 g/L^-1瑞毒霉锰锌+ 0. 30 mL/L^-1爱多收+ 30 mg/L^-1吲哚丁酸。     

蝴蝶兰‘红天鹅’组织培养及快繁技术

[目的]探索‘红天鹅’花梗的不定芽诱导、丛生芽继代增殖和生根诱导技术。[方法]以蝴蝶兰新品种‘红天鹅’的花梗作为外植体,开展组织培养技术研究。[结果]用0.1%的HgCl2消毒外植体20 min,污染率可降低至27.2%,萌芽率达91.0%;不定芽继代增殖培养的最适培养基为MS+6-BA 6.0 mg/L+NAA 0.1 mg/L+AD 5.0 mg/L+香蕉50 g/L+土豆50g/L+蔗糖30g/L+琼脂7.5 g/L,增殖系数达3.80;最适合的生根诱导培养基为1/2MS+NAA0.4 mg/L+香蕉50 g/L+土豆50g/L+C 1.0 g/L+蔗糖15 g/L+卡拉胶7.0 g/L,生根时间为15 d,生根率达100%。[结论]发现了适宜‘红天鹅’的从消毒到增殖,再到生根中各试剂和激素的合理用量,为蝴蝶兰快繁技术发展提供了参考。     

不同培养基成分对薄荷试管苗生根的影响

[目的]筛选薄荷试管苗生根的最佳培养基组合。[方法]以薄荷试管苗茎段为试验材料,探讨不同培养基成分、凝固剂种类及添加量对其生根的影响。[结果]在薄荷试管苗培养过程中,使用琼脂为凝固剂,且添加量为7 g/L的1/2MS培养基时,其生根时间最短,生根数和生根长度较高。[结论]为薄荷试管苗的大规模、优质、高效生产提供理论依据。     

NAA和IBA对福建茶扦插生根的影响

用300 mg/L NAA和300 mg/L IBA处理福建茶1 h、2 h、3 h、4 h,用600 mg/L NAA和600 mg/L IBA处理福建茶1 min、5 min、10 min、20 min,60 d起苗观察生根情况。结果表明,300 mg/LNAA和300 mg/L IBA处理福建茶,NAA处理3 h和IBA处理4 h效果最好,生根率83%和87%;600 mg/L NAA和600 mg/L IBA处理福建茶,NAA处理5 min和IBA处理10 min效果最好,生根率83%和90%。     

葡萄组培苗瓶外生根技术研究

采用不同种类和浓度的生长素诱导葡萄组培苗瓶外生根，并观察组培苗在不同处理基质、不同的温度、不同的生理年龄条件下生根的效果。通过优化技术参数，建立了葡萄组培苗瓶接生根的技术优化体系，结果表明，用浓度为0.3mg/L的IBA浸蘸处理的插条，在温度为27~29℃的环境条件下在基质珍珠岩上培养，瓶苗茎段的生根率可达85.5 %，移栽后苗木的成活率达98 %，相对于其他方法有了较大的提高。该技术的建立有助于实现葡萄工厂化育苗技术的商业化扩大。     

Rhizogenesis of GF677, Early Crest,May Crest and Arm King stem cuttings during the year in relation to carbohydrate and natural hormone content

The rhizogenesis of GF677, Early Crest, May Crest and Arm King stem cuttings during the year was investigated. The results showed significant differences in the rooting percentage between different dates of cutting collection and also between the four cultivars. Among these, GF677 generally had the highest rooting percentage. Rooting of cuttings was high in October, November and February and relatively low in the periods March–September and December–January. Interactions among cultivars were also found.     

核桃楸枝条,插穗中生根抑制物质的含量

通过红心萝卜种子发芽试验表明核桃楸母树体内存在着生根抑制物质．枝皮内的生根抑制物质含量随母树年龄的增加而提高；生根抑制物质含量在高生长旺盛期枝皮内最低，在休眠期含量最高；平茬具有较强的生理复幼作用，根萌枝条皮内的生根抑制物质含量较低；插穗在扦插过程中皮内生根抑制物质含量逐渐降低．