邻体竞争和环境因子对栓皮栎伐桩萌苗表型特征的影响

【目的】阐明栓皮栎(Quercus variabilis)伐桩萌苗邻体竞争及环境因子对其表型特征的影响,探究伐桩萌苗的合理疏伐强度。【方法】以秦岭南坡栓皮栎伐桩萌苗为研究对象,采用修正的大树断面积法建立了伐桩萌苗邻体竞争指数模型,并研究了竞争强度对其表型特征变异的影响,对主要形态指标与竞争强度的关系进行回归分析,对伐桩及其萌苗特征进行主成分分析(PCA),对环境因子与萌苗生长进行相关分析,运用曲线求导方法研究该地区栓皮栎伐桩萌苗合理的疏伐强度。【结果】不同竞争强度下,最大萌苗基径和长度、冠幅面积、总叶片数、侧枝数、平均侧枝长度、总基面积等形态差异明显(P<0.05),萌苗总生物量、侧枝总生物量、叶片总生物量等均随竞争强度的增强而增加;中等竞争强度更有利于当年生萌苗生长;最大萌苗基径和长度、冠幅面积、总基面积、总萌苗数、总叶片数等6项主要形态指标与竞争强度呈幂函数(y=a.xb)关系(P<0.01);主成分分析结果表明,光合器官数量和空间分布对伐桩萌苗更新起主导作用,其次是水和矿质营养的吸收运输能力;相关分析结果表明,光照强度对萌苗生长促进作用明显(P<0.01),而土壤速效氮、速效钾含量的作用较小。【结论】该地区每个伐桩保留萌苗7～9个,能够实现对光、水和矿质营养的最优利用。光照是萌苗更新的决定因子,维持中等或较低的竞争强度,保持一定的萌苗数量,能够充分利用光能,有利于伐桩萌苗生长,缩短更新时间。     

Reduction of duplication in a Brassica oleracea germplasm collection

Summary To reduce the number of accessions in the Brassica oleracea collection of the Centre for Genetic Resources The Netherlands (CGN) groups of accessions were bulked. Accessions in a group were selections from the same landrace or old variety, and were chosen, with the help of crop experts, on the basis of their history and morphology. Since this approach was received rather sceptically in the genebank community, a genetical analysis of some of the groups and their components (named varieties) was made to justify the procedures. A selection of white cabbage and Brussels sprouts, representing two crop types of B. oleracea, was made: eleven white cabbage groups comprising 43 components, and nine Brussels sprouts groups comprising 24 components. Each group and all of its components were described on the basis of electrophoresis of nine isoenzymes on 30 plants. Most components were rightly classified; 16 percent were misclassified. All these misclassifications were within similar groups. It could be concluded that pooling of the components included in this study was justified. In two cases the isozymic patterns suggested that the groups could even have been larger. Only in the case of the two groups of Brussels sprouts Bedfordshire this was a real option. In the other case involving the white cabbage groups Langedijker Bewaar Gewoon, Langedijker Bewaar Graag and Late Herfstdeen this was not an option since these landraces, although having a common genetic background, clearly have a distinct identity as defined by morphology and history. Editorial footnote: We will encourage the publication of further results of research programs in our journal referring to such often controversially discussed concepts, and would appreciate if collections of crops with different breeding systems could be analysed in this respect.     

A simple method for evaluation of sprout characters in soybean

Soybean sprouts are an important year-round vegetable in Asia. Currently, testing of soybean lines for sprout traits is labor intensive and amount of seed required have dictated that testing generally begins after lines have been composited from a plant row in the F₄ or later generations. Sprout testing requires germination of more than 150 seeds, precise watering over several days and movement of seedlings from water baths to growth chambers limiting the number of entries which can be evaluated. The objective of this study was to determine if germinating fewer seeds (10, 20 or 40) on an agar medium is comparable to sprouting over 150 seeds in the traditional method for evaluating soybean genotypes for sprout traits. Sprout growth characteristics were compared for Pungsannamulkong, a known sprout soybean, germinated on 1.0, 1.2, and 1.4% agar medium. Sprout traits 5 days after seeding 20 or 40 seeds on a 1.4% agar medium were very similar to the traditional method. There was no advantage for germinating soaked seeds over dry seeds on the agar medium to determine sprout characteristics. Evaluation of 20 dry seeds on a 1.4% agar medium of eight known sprout cultivars was comparable to the traditional method for measuring sprout characteristics for each cultivar. The agar method requires less labor, fewer seeds, no watering schedules or water baths and less growth chamber space than the traditional method to test genotypes for sprout characteristics. This allows more lines from soybean breeding populations in earlier generations to be evaluated. The agar method will improve the efficiency for evaluating soybean breeding lines for sprout traits.     

The production of inbred lines of brussels sprouts with dominant S-alleles

Summary The best sources of Brussels sprout inbred lines with both good agronomic characters and high self-incompatibility are likely to be cultivars of reasonably good agronomic type which have not been too intensively selected. Comparison of three cultivars of different agronomic quality showed that the cultivars of poor and moderate quality had about 55% of plants with a dominant S-allele, but the most highly selected cultivar had only 25% of such plants. A programme of S-allele screening is suggested which incorporates the minimum number of tests required to determine whether or not a particular plant has a dominant S-allele. A survey of S-alleles present in commercial F₁ hybrids showed that the frequency of dominant S-alleles was only 19% in hybrids released prior to the end of 1971, but was 50% in hybrids released since 1971.     

Classification of S-alleles by their activity in S-heterozygotes of brussels sprouts (Brassica oleracea var. Gemmifera (DC.) Schultz)

Summary Over a period of many years, data on dominance relationships of S-alleles in Brussels sprouts were collected at URL and IVT. The level of activity of S-alleles in heterozygotes was assessed on the basis of the number of pollen tubes that penetrated into the stigma. 209 out of 210 possible combinations between 21 S-alleles were used for this investigation. The S-alleles were grouped separately for activity in pollen and style on the basis of their sensitivity to lose activity in S-heterozygotes. Besides S-allele interaction per se, activity was found to be influenced by environment and genetic background.Results suggest that in stigma, co-dominance is the normal pattern and that deviations are caused by factors other than S-allele interaction as such.In pollen, only three truly recessive alleles were found. Besides several combinations with mutual weakening in pollen, examples of independent weakening were found.     

Routine large-scale electrophoresis for plant breeding. An example with F1 seeds of Brussels sprouts (Brassica oleracea var.gemmifera)

Summary A routine method of large-scale electrophoresis is proposed for use in plant breeding. The method can be applied both with research and teaching and does not require sophisticated apparatus. A skilled laboratory technician can thus handle 768 samples a day. Within a series of electrophoretic investigations the individual electrophoresis can be stopped at any time, while the other investigations in the series continue.     

酵素黄豆芽全产业链生产管理技术

近年来,酵素农产品已成为市场新宠。为了充分发挥酵素黄豆芽营养丰富、保健功能突出、风味清香脆嫩、深受消费者喜爱的特点,在深入研究酵素对黄豆芽生长发育、产量品质等影响的基础上,完成了酵素黄豆芽全产业链生产技术规范,得到了中国食品工业协会豆制品专业委员会专家的好评,并实现了批量生产和供应。实践表明:科学使用酵素益生菌会在黄豆芽生产中取得良好的效果,同常规生产相比,豆芽发芽率高,生长速度快,生产周期短,豆芽抗性强、腐烂少、品质优、口感好,现已广泛被生产者和消费者认可。     

苦荞发芽过程中游离氨基酸含量的变化

【目的】探讨苦荞不同发芽时期游离氨基酸含量的变化规律,为苦荞的综合利用及相关功能性产品的开发提供依据。【方法】采用氨基酸自动分析仪,分别对黔苦5号、沽源苦荞、西荞1号、川荞1号4个苦荞品种种子发芽0,3,6,9,12 d的游离氨基酸进行定量检测,分析氨基酸间含量变化的相关性;通过主成分分析,判断发芽过程中氨基酸总量发生变化的主要特征氨基酸;应用聚类分析,研究游离氨基酸的变化规律。【结果】苦荞发芽前后游离氨基酸含量变化较大,发芽12 d后,黔苦5号、沽源苦荞、西荞1号、川荞1号总氨基酸含量分别由发芽前的5.40,5.31,4.03,3.82 mg/g增加至16.26,19.27,17.91,15.79 mg/g;苏氨酸、谷氨酸和亮氨酸含量变化与多种氨基酸呈相反趋势,丝氨酸、天冬氨酸等9种氨基酸是苦荞发芽过程中含量发生变化的主要特征氨基酸,发芽6,9,12 d时4种苦荞芽的氨基酸含量不能明显区分。【结论】苦荞发芽前后氨基酸变化较大,可根据产品需要选择发芽时间。     

不同留茬高度处理对柠条更新能力的影响

为促进柠条林人工更新和提高其利用率,文章对24年生灌木状柠条人工林进行0 cm、5 cm、10 cm 3种留茬高度处理.结果表明:(1)柠条再生能力较强,第1次平茬后新生枝株高,冠幅迅速增长,且能保持良好的生长状态,生物效益显著.(2)离地面10 cm平茬处理的效果优于其余2种处理.     

杉木萌芽更新造林技术初探

分析了影响杉木萌芽更新造林的主要因子后，提出了萌芽更新造林的技术要点，以及提高萌芽杉木林生产力的措施。以利第２代杉木林能够持续健康的发展。