圆果黄麻雌性不育突变体鉴定及其生理生化特性初步研究

为研究圆果黄麻（Corchorus capsularis L．）粤圆6号不育突变体的类型及不育机理,以粤圆6号及其不育突变体为实验材料,对其花器官及花粉粒进行了形态观察、碘染实验、体外萌发实验及田间授粉实验,结果表明,粤圆6号突变体为雌性不育。对两个材料发育不同时期功能叶和花蕾中的可溶性糖和可溶性蛋白含量进行了测定,结果表明,可溶性糖和可溶性蛋白在不同时期均表现出动态变化。雌性不育突变体功能叶中的可溶性糖在现蕾前期的含量略低于正常可育材料,进入现蕾期和结果期,其可溶性糖却比可育材料分别高出16．0％、33．3％,而花蕾组织中的可溶性糖比可育材料降低了15．5％;可育材料3个时期的功能叶及花蕾组织中可溶性蛋白的表达量分别比不育突变体高出3．9％、29．2％、79．1％、11．9％。上述代谢表达差异可能与雌性不育有关。     

Characterization of a lignified secondary phloem fibre-deficient mutant of jute (Corchorus capsularis)

BACKGROUND AND AIMS: High lignin content of lignocellulose jute fibre does not favour its utilization in making finer fabrics and other value-added products. To aid the development of low-lignin jute fibre, this study aimed to identify a phloem fibre mutant with reduced lignin. METHODS: An x-ray-induced mutant line (CMU) of jute (Corchorus capsularis) was morphologically evaluated and the accession (CMU 013) with the most undulated phenotype was compared with its normal parent (JRC 212) for its growth, secondary fibre development and lignification of the fibre cell wall. KEY RESULTS: The normal and mutant plants showed similar leaf photosynthetic rates. The mutant grew more slowly, had shorter internodes and yielded much less fibre after retting. The fibre of the mutant contained 50 % less lignin but comparatively more cellulose than that of the normal type. Differentiation of primary and secondary vascular tissues throughout the CMU 013 stem was regular but it did not have secondary phloem fibre bundles as in JRC 212. Instead, a few thin-walled, less lignified fibre cells formed uni- or biseriate radial rows within the phloem wedges of the middle stem. The lower and earliest developed part of the mutant stem had no lignified fibre cells. This developmental deficiency in lignification of fibre cells was correlated to a similar deficiency in phenylalanine ammonia lyase activity, but not peroxidase activity, in the bark tissue along the stem axis. In spite of severe reduction in lignin synthesis in the phloem cells this mutant functioned normally and bred true. CONCLUSIONS: In view of the observations made, the mutant is designated as deficient lignified phloem fibre (dlpf). This mutant may be utilized to engineer low-lignin jute fibre strains and may also serve as a model to study the positional information that coordinates secondary wall thickening of fibre cells.     

Mycoflora and aflatoxin production in pigeon pea stored in jute sacks and iron bins

The mycoflora, moisture content and aflatoxin contamination of pigeon pea (Cajanus cajan (L.) Millisp) stored in jute sacks and iron bins were determined at monthly intervals for a year. The predominant fungi on freshly harvested seeds wereAlternaria spp.,Botryodiplodia theobromae, Fusarium spp. andPhoma spp. These fungi gradually disappeared from stored seeds with time and by 5–6 months, most were not isolated. The fungi that succeeded the initially dominant ones were mainly members of the generaAspergillus, Penicillium andRhizopus. Population of these fungi increased up to the end of one year storage. Higher incidence of mycoflora andAspergillus flavus were recorded in jute-sack samples throughout the storage period. The moisture content of stored seeds was found to fluctuate with the prevailing weather condition, being low during the dry season and slightly high during the wet season. The stored seeds were free of aflatoxins for 3 and 5 months in jute sacks and iron bins respectively. The level of aflatoxins detected in jute-sack storage system was considerably higher than that occurring in the iron bin system. Of 196 isolates ofA. flavus screened, 48% were toxigenic in liquid culture (54% from jute sacks and 41% from iron bins).     

黄麻栽培种圆果种×长果种的种间杂交研究

１９８９—１９９１年对黄麻栽培种圆果种（Ｃｏｒｃｈｏｒｕｓｃａｐｓｕｌａｒｉｓ）和长果种（Ｃ．ｏｌｉｔ－ｏｒｉｕｓ）选用了具有不同茎色和腋芽性状的材料做了６个组合,获得１３４株杂种Ｆ＿１苗。但苗株发根不良,在移栽后两周陆续死亡,最后幸存ＲＲ－５×（ＢＬ×７７－１９）Ｆ＿１组合中两株植株并开花、结果。Ｆ＿１均有腋芽,表现为父本的性状;花果形状偏向母本;茎色红同双亲。这两株的Ｆ＿２,茎色和腋芽性状分离成４种表现型：红茎或青茎有腋芽及红茎或青茎无腋芽。其中红茎有腋芽的生长较快。对种间杂交技术、亲本间的花粉与柱头亲和性、杂交花的胚珠受精情况及染色体构型等方面也作了观察、研究。     

罕见异位核型t(1;3),T(9;19)两例报告

TwoRareCasesofChromosomeTranslocationt(1;3)andt(9;19)WeiRongshangZhangHaiduanWangAiqinHeChunna(LaboratoryofGenetics,NanjingHospitaloftheAirForceofPLANanjing210002)例1男,28岁,结婚2年余,妻27岁,妊娠3次,第1胎孕5个月胎死宫内,第2胎7 月早产后夭折,第3胎5个     

黄麻种质资源遗传多样性的SRAP分析

为明确黄麻(Corchorus L.)种质资源的遗传多样性,采用SRAP分子标记方法,对来自13个国家的两个黄麻栽培种及野生种共96份黄麻种质资源进行了分析。研究结果如下:(1)供试黄麻种质资源之间的遗传距离在0.0169至0.9667之间,变幅较大,其中近缘野生种与其他种质的遗传距离最大,基本在0.8以上;圆果栽培黄麻与其他种质的遗传距离最小,平均<0.5。(2)当在聚类图上遗传距离为0.53处划切割线L₁时,96份黄麻种质资源被分为两个大类群(Ⅰ、Ⅱ)、一个小类群(Ⅲ)和5个独立个类。(3)当在遗传距离为0.33处作切割线L₂时,各大类群被分为不同的亚类群,并表现出按地域聚类的趋势。(4)供试黄麻种质资源基于SRAP分子标记的聚类与形态学上的表现并不完全一致。     

26份黄麻种质资源产量性状的主成分聚类分析及其评价

为了解所收集黄麻种质资源的产量性状及遗传多样性,为黄麻育种和生产利用提供科学依据。本研究对26份黄麻品种(系)的8个产量性状进行主成分估算,并以前3个主成分为基础,分别作聚类分析和二维排序图。结果表明:参试材料产量相关性状的变异系数为2.54%~14.70%,其中,皮厚、单株鲜皮重、单株鲜骨重、鲜皮晒干率、单株干皮产量5个产量性状的变异系数超过10%,说明产量性状的变异潜力较高。主成分分析表明,单株鲜皮重因子、鲜皮晒干率因子、分枝高因子这3个主因子提供了原始性状88.247%的信息;在欧氏距离聚类图中,当取值D=2.15时,可把26个黄麻育成品种(系)分成4类,第Ⅰ类群包含18份材料,占69.23%,第Ⅱ类群包含5份材料,占19.23%,第Ⅲ类群只有1个品种(系),第Ⅳ类群包括黄麻179和宽叶长果2份材料,各个类群具有不同的特点,在黄麻杂交育种上可根据不同类别的特点加以利用;二维排序表明9(09品-11)、11(89m5-83)、12(09繁-7)、19(福黄麻1号)、21(黄麻831)、25(Y007-10)等6个高产品种(系)的3个主成分构成因子协调最好。将聚类分析和二维排序分析结合起来的分析方法,能较好地为黄麻品种改良以及亲本利用提供科学依据。     

国外引进优良黄麻种质生物学鉴定与利用

通过对从国外引进的12份黄麻优异种质进行3年的生物学鉴定,结果表明：引进种质大多为晚熟、绿茎、有腋芽,披针或卵圆形叶,生长较整齐。其中O—4叶片蜡质含量明显高于我国品种;O-5叶柄紧贴主茎。短光照处理未发现对光不敏感品种,但分期播种未见早花现象。所有品种在我国黄麻主产区均能正常生长与收获纤维,但晚熟品种只能在华南麻区才可收获成熟种子。     

用ISSR标记检测黄麻野生种与栽培种遗传多样性

利用ISSR标记对黄麻属((Corchorus)10个种27份材料的遗传多样性进行分析,25个ISSR引物共扩增出283条带,平均每个引物扩增出10．48条带,多态性条带比例(PPB)为92．85％;种间遗传相似系数在0．33～0．97之间。表现出丰富的遗传多样性．系统聚类结果显示,第I、Ⅲ类群均为黄麻属8个种11份原始野生种,种间存在丰富的遗传多样性;第Ⅱ类群为黄麻两个栽培种及其近缘野生种,共16份材料。种遗传相似性较高;基因组聚类结果与经典分类相符．利用分子标记技术研究初步可以认为。荨麻叶种为最原始的黄麻野生种之一;三室种21C为三室种的一个变种;甜麻为一个尚待定性的野生种．同组材料的RAPD和ISSR分析结果,具有较高的相似性和可信度．     

Production of extracellular polysaccharide by Bacillus megaterium RB-05 using jute as substrate

Bacillus megaterium RB-05 was grown on glucose and on “tossa-daisee” (Corchorus olitorius)-derived jute, and production and composition of extracellular polysaccharide (EPS) were monitored. An EPS yield of 0.065 ± 0.013 and of 0.297 g ± 0.054 g⁻¹ substrate after 72 h was obtained for glucose and jute, respectively. EPS production in the presence of jute paralleled bacterial cellulase activity. High performance liquid chromatography (HPLC), matrix assisted LASER desorption/ionization-time of flight (MALDI-ToF) mass spectroscopy, and fourier transform infrared (FT-IR) spectroscopy demonstrated that the EPS synthesized in jute culture (JC) differed from that synthesized in glucose mineral salts medium (GMSM). While fucose was only a minor constituent (4.9 wt.%) of EPS from GMSM, it a major component (41.9 wt.%) of EPS synthesized in JC. This study establishes jute as an effective fermentation substrate for EPS production by a cellulase-producing bacterium.