悬铃木果实生长发育的化学调控

采用化学调控法,研究植物生长调节剂等化学药剂对悬铃木当年果实生长发育的影响。结果表明：与对照相比,在9个药剂组合中,D（40％）处理和D（10％）＋C（10％）处理对果实生长发育的抑制效果最佳。使悬铃木当年果实减少率达75％以上,果实的鲜重和含水率明显降低,细胞质膜透性明显增大,果实生长发育明显受阻,并且对悬铃木叶片的副作用较小。研究结果为悬铃木果毛污染的化学调控提供依据。     

根结线虫在中国的新纪录种——西班牙根结线虫(Meloidogyne hispanica Hirschmann)

 A root-knot nematode, Meloidogyne hispanica Hirschmann, was first described and illustrated from roots of papaya in Danzhou, Hainan province in China. The perineal pattern of female was characterized by oval shaped to rectangular with a low dorsal arch; dorsal striae varied from fine and wavy to coarse; lateral lines forked with fringe-like striae between lines and phasmidial ducts distinctly appeared. Male had high and rounded head region with labial disc and medial lips fused to form elongate lip structures. Second-stage juve-nile had distinct body annules and stylet with rounded, posteriorly sloping knobs, and the tail terminus was slender with indistinct hyaline. This Chinese new record of M. hispanica had a unique esterase phenotype (S2-M1) which was different from that of other Meloidogyne species.     

芡欧鼠尾草的组织培养和快速繁殖

以芡欧鼠尾草(Salvia hispanica)成熟种子为外植体,1/2MS为基本培养基,研究不同浓度的外源激素对愈伤组织的诱导、增殖和生根的影响,从而初步建立了芡欧鼠尾草组织培养的快速繁殖体系。结果表明,诱导种子愈伤组织的最适宜培养基为1/2MS+10.0mg·L~(-1) 6-BA+1.0mg·L~(-1) NAA+0.4mg·L~(-1) ZT,诱导率为66.5%;不定芽增殖的最适培养基为1/2MS+3.0mg·L~(-1) 6-BA+0.5mg·L~(-1) NAA,增殖倍数为7.69;生根的最适培养基为1/2MS+0.5mg·L~(-1) NAA,生根率达100%,平均生根数为5.68;移栽后植株生长良好,成活率较高,达97%。     

Variation and heritability of seed mass in chia (<Emphasis Type="Italic">Salvia hispanica L.</Emphasis>)

Variation and heritability of seed mass in the Mesoamerican crop chia, Salvia hispanica L. was studied to examine the feasibility of selection for the trait. Genotypic variation in seed mass in wild/cultivated and domesticated accessions of chia from different origins was assessed. Broadsense heritability of seed mass was estimated using variances associated with parental and F2 generations derived from two crosses and from the response to one cycle of selection. Significant (P . 0.0001) genotypic variation was observed among accessions. Mean seed mass for domesticated accessions (14.84 mg/100 seeds) was greater than that of the wild accessions (11.29 mg/100 seeds) by 31%. The heritability of seed mass was relatively high in chia (0.75), suggesting that this trait is under strong genetic control. This conclusion was supported by a single selection cycle from the F2 to F3 generation that produced a 16% increase in mean seed mass. The realized heritability estimated based on this one cycle of selection also was 0.75. These observations indicate that gains from selection in chia seed mass are possible when mass selection is conducted in early generations. Basic information is thus provided for future breeding efforts in a species for which little or no knowledge of inheritance currently exists.     

Microsatellite analysis of genetic population structure of the endangered cyprinid Anaecypris hispanica in Portugal: implications for conservation

The endangered fish species Anaecypris hispanica is restricted to eight disjunct populations in the Portuguese Guadiana drainage. The genetic structure of these populations was studied in order to determine levels of genetic variation within and among populations and suggest implications for conservation of the species. Based on five microsatellite loci, the null hypothesis of population homogeneity was tested. Tests for genetic differentiation revealed highly significant differences for pairwise comparisons between all populations, and substantial overall population subdivision (F_ST=0.112). All sampled populations contained unique alleles. Our findings indicate marked genetic structuring and emphasise limited dispersal ability. The high levels of genetic diversity detected within and among A. hispanica populations suggest, however, that the observed fragmentation and reduction in population size of some populations during the last two decades, has impacted little on levels of genetic variability. Data imply that most A. hispanica populations should be managed as distinct units and that each has a high conservation value containing unique genetic variation. It is argued that geographic patterns of genetic structuring indicate the existence of eight management units.     

3种药食植物雾培生长效果研究

采用雾培的方法,对奇亚、土人参和刺芫荽3种药食植物进行生长效果研究,结果表明,雾培的奇亚株高和根长分别是土培的1.6和3.8倍,雾培的土人参和刺芫荽植株平均鲜重分别是土培的2.9和3.4倍,说明雾培能明显促进3种药食植物的生物量积累。     

西班牙根结线虫rDNA特性及其检测方法

通过对rDNA的ITS区和IGS2区进行PCR扩增并对产物测序,比较分析了西班牙根结线虫与中国4种常见的南方根结线虫、爪哇根结线虫、花生根结线虫和北方根结线虫群体rDNA的ITS区和IGS2区的序列差异,选择限制性内切酶TaqⅠ对IGS2区的PCR扩增产物进行酶切,获得了西班牙根结线虫的554 bp的特异性条带.表明用此方法可以明显将西班牙根结线虫与其他4种常见的根结线虫群体区分开,其灵敏度可达到单条根结线虫二龄幼虫.     

3种鼠尾草属植物的核型分析

为了解新种质芡欧鼠尾草与鼠尾草属常见植物一串红、一串蓝之间的亲缘关系,并为其远缘杂交和遗传改良提供基础,本实验在细胞遗传学水平,对鼠尾草属芡欧鼠尾草、一串红、一串蓝3种植物染色体核型进行分析。结果显示芡欧鼠尾草二倍体体细胞染色体数目为12条,核型公式是2n=12=2m+2sm+8st,核型不对称系数(AS.K%)为74.9%,核型分类标准属于“3A”型;一串红二倍体体细胞染色体数目为44条,核型公式是2n=44=34m+2sm+8st,核型不对称系数(AS.K%)为62.4%,核型分类标准属于“2A”型;一串蓝二倍体体细胞染色体数目为18条,核型公式是2n=18=12m+6sm,核型不对称系数(AS.K%)为59.0%,属于“2A”型。通过核型分析,芡欧鼠尾草、一串红、一串蓝的染色体具有明显的差异性,所以认为这3种鼠尾草属植物的亲缘关系较远。     

Barberry plays an active role as an alternate host of Puccinia graminis in Spain

Stem rust, caused by Puccinia graminis, is a destructive group of diseases. The pathogen uses Berberis species as alternate hosts to complete its life cycle. B. vulgaris and the endemic species B. hispanica and B. garciae are present in Spain. The objective of this study was to investigate the functionality of the indigenous barberry as alternate hosts. Field surveys were conducted in 2018 and 2019 in Huesca, Teruel and Albacete provinces of Spain. Aecial samples on barberry were analysed via infection assays and DNA analysis. B. garciae was predominant in Huesca and Teruel provinces, often found in the field margins of cereal crops. Aecial infections on B. garciae were observed in May and uredinial infections on cereal crops in June. Scattered B. hispanica bushes were occasionally found near cereal crops in Albacete, where aecial infections on B. hispanica were observed in June when most cereal crops were mature. Infection assays using aeciospores resulted in stem rust infections on susceptible genotypes of wheat, barley, rye and oat, indicating the presence of the sexual cycle for P. graminis f. sp. tritici, f. sp. secalis and f. sp. avenae. Sequence analyses from aecial samples supported this finding as well as the presence of Puccinia brachypodii. This study provides the first evidence that indigenous Berberis species play an active role in the sexual cycle of P. graminis under natural conditions in Spain.