红、黄麻分期收剥对纤维产量和品质的影响

试验在杭州进行,按不同收期对红、黄麻纤维产量和品质进行了测定。结果表明,目前普遍种植的迟熟品种,直至10月上旬其纤维产量仍未显著地超过所有供试的中熟品种。由于迟熟品种每年需要向华南购籽,花费较大,以及不能充分地利用有利的生长季节,迟熟品种的经济效益可能不及某些高产的中熟品种。因此,选用高产的中熟红、黄麻品种     

大麻-黄麻/红麻1年2茬种植技术初探

麻类是国内一种重要的经济作物。针对市场上麻纤产品需求日益增加,麻类作物种植面积不断减少的问题,通过田间小区试验,对大麻作前茬,大麻收获后接茬种植黄麻/红麻的种植模式进行研究。结果显示:大麻-黄麻种植模式,麻纤总产量比单独种植大麻或黄麻分别最低增产90.8%和34.2%。大麻-红麻种植模式,麻纤总产量比单独种植大麻或红麻分别最少增产92.7%和28.8%;同时,大麻和黄麻/红麻接茬种植,其净收益和产投比均较单独播种时增加,而且6月20日左右接茬净收益和产投比最高。从麻纤产量、净收益和产投比等指标综合来看,大麻-黄麻/红麻的种植模式可以实现麻类的增产、增收,提高农民的经济收益,值得大面积应用推广。     

黄麻核心种质的遴选

遴选黄麻核心种质可为黄麻种质创新及新品种选育奠定基础。本研究以300份黄麻种质资源为基础,基于SSR分子标记和农艺性状考察,结合地理来源构建核心种质。结果表明,11个农艺性状变异系数变幅在13.06%～84.87%,表现出丰富的遗传多样性。按农艺性状聚类分析可划分为8个类群,按分子标记聚类可划分为10个类群。结合2个聚类分析、地理位置并按比例取样,建立一个由108份品种(系)组成的预选核心种质。采用44对SSR引物对其进行遗传差异分析,在遗传相似系数为0.65时,可把108份品种(系)分成圆果种和长果种两大类。根据遗传差异分析,剔除遗传相似系数大于或等于0.85的遗传冗余,获得84份品种(系)的核心种质,其中圆果种60份和长果种24份。比较84份核心种质与300份种质的农艺性状变异系数及Shannon-Wiener指数发现,两者之间相差不大,表明遴选的84份核心种质可以最大限度代表300份黄麻种质资源的遗传多样性加以利用和保存。     

Comparing weed and crop seedling response to pre-emergence pendimethalin application in Corchorus olitorius and Abelmoschus esculentus

Field experiments and bioassay tests were carried out to evaluate the relative response of the crops, tossa jute (Corchorus olitorius L.) and okra [Abelmoschus esculentus (L.) Moench], and their associated weeds to pre-emergence application of pendimethalin at 0.33, 0.66, 0.99, 1.32 kg ai ha⁻¹ and a pendimethalin+atrazine tank mixture at 1.32+2.05 kg ai ha⁻¹. Bioassay tests were carried out using herbicide solutions of corresponding concentrations and herbicide-treated soil. Field application of pendimethalin at 0.66 kg ai ha⁻¹ and the herbicide mixture in both crops effectively controlled most seedling weeds including Rottboellia cochinchinensis. Euphorbia heterophylla and Calopogonium mucunoides, which persisted from 2 weeks after treatment (WAT) were not controlled. Herbicide application during crop establishment markedly inhibited the growth of both seedling weeds and crops. The mixture caused the highest weed and crop injury. Pendimethalin at 0.33 kg ai ha⁻¹ had minimal effect on these crops. Weed growth, weed tolerance of herbicide treatment and crop seedling injury were higher in tossa jute than that in okra, under the conditions of this study. The use of low pendimethalin doses in an integrated weed management system will ensure effective control of seedling weeds, and prevent crop injury and residue accumulation in edible plant produce.     

黄麻SSR标记与纤维产量性状的相关性

Simple sequence repeat (SSR) markers correlated to fiber yield traits would be a beneficial tool for molecular marker-assisted breeding in jute. In this study, 397 SSR markers were screened from 311 jute germplasms by the phenotype identification from 2016 to 2018 and 116 pairs of primers. The correlation analysis between SSR markers and fiber yield related traits by SPSS revealed that the range of the coefficient of variation related to 9 fiber traits was from 13.05% to 76.78%, indicating a comprehensive genetic variation. The correlation analysis of the agronomic traits showed that there were significantly correlations among these traits. The average correlation coefficient between branch height and nodes of main stem was the highest (r = 0.931), followed by the correlation coefficients (r = 0.781) of fresh bark weight per plant and fresh stem weight per plant and the coefficients (r = 0.779) of dry bark weight and fresh bark weight per plant. Analysis of variance (ANOVA) showed that the traits of main stem nodes, number of branches, plant height and branch height were relatively stable in different years with the higher broad heritability capacity. Furthermore, the SSR markers associated with fiber yield related traits were identified by Pearson correlation method. Stepwise regression analysis among each trait associated SSR markers indicated that there were six markers associated significantly with fiber yield related traits, and phenotypic variation explained by each SSR marker varied from 3.9% to 22.5%. These results will accelerate the development of molecular design breeding in jute.     

栽培种黄麻花粉形态扫描电镜观察

用光学显微镜和扫描电子显微镜观察测量了黄麻圆果种19个品种和长果种3个品种花粉的形态和大小。栽培种黄麻花粉粒为长球形,具3个萌发沟,长条状或狭缝状,极面不汇合,外壁具不规则5～7边形的网状纹饰,每个网眼具有大小和数目不等的许多小孔。不同种和品种花粉的大小、形状和外壁纹饰皆不同。长果种的花粉粒较大,网眼较大,为不规则长多边形;圆果种的花粉粒较小,网眼多为不规则偏方的多边形。花粉粒形状和外壁纹饰均与品种的腋芽有无关系不大,与茎色、叶柄色等特征无关,而与品种的地理来源、亲缘关系和生育期似有联系。不同地理来源的品种其花粉粒形态差异较大;亲缘关系较近的品种花粉粒形态差异较小;生育期较长的品种花粉粒似较长,而生育期短的品种花粉粒较短.初步研究结果表明,黄麻花粉的形态特征可能为黄麻育种和种、品种分类提供参考依据。     

改性黄麻纤维和酚醛树脂复合材料的力学性能

采用碱溶液(20 g/L NaOH)、热(140℃)处理方法对黄麻纤维进行改性处理,采用热压工艺将纤维与酚醛树脂制成复合材料。通过力学性能、冲击断口形貌对复合材料进行表征。结果表明:当碱处理时间不超过2 h、热处理时间不超过3 h时,黄麻纤维增强酚醛树脂基复合材料的拉伸强度和冲击强度均有不同程度提高。碱处理2 h的黄麻纤维增强酚醛树脂基复合材料的拉伸强度和冲击强度提高幅度最大,分别为13.5%和25%;冲击断口分析结果表明,热处理纤维与基体的界面结合强度高于碱处理纤维,断口呈平面化。     

不同处理方法对菜用黄麻种子萌发的影响

为了提高菜用黄麻种子的发芽率,保证出苗的整齐度,采用沙子研磨、热水浸种、98%浓硫酸浸种和40%氢氧化钠浸种共4种方法对菜用黄麻桂麻菜1号和桂麻菜2号种子进行处理。结果表明:沙子研磨、热水浸种、98%浓硫酸浸种处理对种子的发芽势和发芽率均有显著地影响。桂麻菜1号和桂麻菜2号在种子与沙子体积比1:4、研磨时间为8 min时,种子发芽率最高分别为78.0%、86.3%;热水80℃浸种8 min时,种子发芽率最高分别为86.3%、83.0%;98%浓硫酸浸种处理30 min时,桂麻菜1号发芽率最高达78.3%,桂麻菜2号在浸种10 min时,发芽率最高达87.3%。40%氢氧化钠浸种处理对菜用黄麻种子发芽率的影响不明显。在这4种菜用黄麻种子处理方法中,热水浸种方法易于操作,处理时间短,成本低廉,适合生产上推广运用。     

不同处理对黄麻纤维木质素去除及织物性能的影响

本文研究了草酸铵、漆酶以及木聚糖酶单独或联合处理对黄麻机织布中木质素的去除作用及对织物褶皱、力学性能的影响。结果表明,漆酶单一处理仅能去除少量的木质素,联合处理可提高木质素的去除效率,以草酸铵、木聚糖酶、漆酶联合处理效果最好。在ATR红外谱图中,草酸铵、木聚糖酶、漆酶联合处理后的黄麻机织布较未处理织物在1594 cm-1、1506cm-1和1424 cm-1处的木质素芳香族特征吸收峰,1731 cm-1和1646 cm-1处的木质素羰基特征吸收峰及1242 cm-1-1031 cm-1处的半纤维素醚键特征吸收峰均有减弱,说明经草酸铵、木聚糖酶、漆酶联合处理后黄麻纤维表面木质素和半纤维素含量降低。经处理后黄麻机织布褶皱回复角提高,其中草酸铵、木聚糖酶、漆酶联合处理褶皱回复性最佳。漆酶单独处理后黄麻机织布断裂强力和断裂延伸率均提高,联合处理后断裂强力降低,断裂延伸率提高。     

黄麻应用核心种质的DNA分子身份证构建

It is important to construct and study the applied core collection in order to promote jute genetic breeding and explore excellent genes. In this study, the applied core collection in jute, including 61 accessions divided into 16 application-oriented features, such as high yield, high quality, disease resistance and so on, was established based on the field performance from 300 jute germplasm. 12 fluorescent core primers were screened from 46 pairs of core primers. Fluorescence labeled capillary electrophoresis was used to analyze the polymorphism of these 12 pairs of primers, and a total of 140 polymorphism sites were detected. The precise DNA molecular ID cards were constructed by the combination of the 12 core primer pairs from the data coded in the form of numbers and English letters. Bar code and quick response code DNA molecular were established and can be quickly scanned and recognized by electric gadget. These results could be beneficial to increase the application efficiency and rapid molecular identification in jute germplasm resources.