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ozgnth@sina.com。 《勤云标准版测试》2006,(3)
用黔糖4号作供试材料,选择蔗茎嫩梢部茎腋芽作接种外植体进行离体培养;外值体消毒采用75%酒精浸泡8~10s后用0.1%HgCl2消毒15min复合消毒,多次清洗再接种;腋芽诱导培养基采用(液态)1/2MS 0.25mg/L(6-BA);丛芽诱导增殖培养基采用(固态)MS 2.5mg/L(L-BA) 0.2mg/L(KT),每隔15~20d转基继代一次,繁殖倍数可达30倍以上;生根培养基采用(固态)1/2MS 3.0mg/L(NAA) 0.1mg/L(IBA),添加2.5mg/L的MET,使丛苗根粗苗壮;炼苗后移至“沙土沙”的苗床假植,再单株假植至20cm左右高的苗时进行大田定植;摸索总结了一套黔糖4号腋芽离体快繁种苗技术,并详细介绍了操作要领,提出了有关环节中应注意的五个问题和相应的解决方法。 相似文献
3.
R. Godoy 《Agroforestry Systems》1990,12(2):163-172
In this paper the author: (a) discusses the uniqueness of rattan among non-timber forest products, (b) examines the financial and the economic profitability of smallholder rattan cultivation, and (c) outlines a strategy for expanding smallholder rattan plantations among non-traditional producers. 相似文献
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J. C. Skinner 《Euphytica》1982,31(2):523-537
Summary The efficiency of family selection in bunch-planted sugareane seedlings was investigated by planting 40 families (20 proven and 20 experimental) as bunches and as single seedlings in adjoining replicated trials. A replicated trial planted the following year. using stem cuttings from random seedlings of each family. provided an independant estimate of the value of each family.Five methods were used to compare bunch and single planting, namely theoretical and realized gains from selection, correlations between the seedling and evaluation trials, discrimination based on proven cross classes, and discrimination based on production of advanced selections. Overall, bunch planting was inferior to single planting for family selection. It was promising for only one method of evaluation (proven cross classes) but this, combined with the relatively small area required for bunch-planted seedlings, indicates that family selection may be possible in such plantings. The use of a number of methods of evaluation showed that incorrect conclusions were likely if only one method were used, and revealed deficiencies in methods which would otherwise be considered satisfactory. The project provided a basis for the design of more critical experiments.The components of weight of cane, namely number of stalks and weight per stalk, are negatively correlated, and showed different relationships with yield in the seedling and evaluation trials. Weight per stalk was an important component in seedling trials, with number of stalks by far the main component in the evaluation trial which was planted by the commerical method using stem cuttings.Family selection based on number of stalks and sugar content, preceding mass selection, is likely to provide a better selection system than the usual mass selection in bunch-planted seedlings.Families do not express their full genetic potential in original seedlings. whether bunch or single planted: trials planted from stem cuttings give more effective family selection. Furthermore, family selection for the most important characters (net merit grade and weight of sugar) was much more effective in ratoon than in plant crops. These results have important implications for the practical selection program, further experimental work being necessary to specify the most efficient system. 相似文献
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以甘蔗糖蜜为原料,发酵合成茁霉多糖发酵的初始条件。以生物量和多糖产量为依据,在确定以甘蔗糖蜜发酵合成茁霉多糖的初始发酵培养基的基础上,研究影响甘蔗糖蜜发酵合成茁霉多糖条件的因素。研究结果表明,以甘蔗糖蜜为原料发酵合成茁霉多糖的生物合成条件是:接种量为15%,发酵温度为30℃,在充足供氧条件下的发酵时间为144h。 相似文献
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D. L. Jennings 《Euphytica》1982,31(3):953-956
Summary Gene H determines cane hairyness in raspberries and was reported to facilitate escape from infection by Botrytis cinerea and Didymella applanata. However, experiments with mycelial inoculations of wounded canes showed that it conferred a form of resistance which was evident for a long period after the establishment of infections by these pathogens. The gene also contributed to the resistance of fruit to B. cinerea and of canes to Leptosphaeria coniothyrium. Alternative hypotheses to explain these observations are discussed: two based upon its possible genetic linkage with a gene or genes for resistance and one based upon its possible pleiotropic effects. 相似文献
9.
Inter-relationships among cane yield and commercial cane sugar and their component traits in autumn plant crop of sugarcane 总被引:1,自引:0,他引:1
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
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