银杏非根尖细胞的染色体观察

由于雌雄异株植物银杏的种子及幼苗无法区分性别 ,因而在研究其性别时不能用传统的种子萌发取根的方法来进行染色体制片 ,而从雌、雄成株上取根也不切实可行。为解决该问题 ,本文以银杏的幼小花药、叶、胚珠以及小孢子、雌配子体游离核为材料 ,主要采用放线菌酮 (Cycloheximide,1 0 0mg/kg)作预处理药物 ,常规制片均得到了优良的染色体标本。     

RAPD markers related to sex locus in Populus tomentosa

By using the methods of random amplified polymorphic DNA (RAPD) and bulked segregate analysis (BSA), we identified markers that are linked to the sex determination in the dioecious Populus tomentosa. Male and female bulks were created through rough mixing equal amounts of its five individual DNA. A total of 88 primers were screened. Twelve primers produced clear patterns with at least one band that appeared to be polymorphic between the two bulks. Subsequently, five male and female individuals were analyzed with those 12 primers, and only S60 (ACCCGGTCAC) could generate a common 1800 bp DNA fragment in all five male individuals and male pool but not in any female individuals. It can be concluded that the gender of P. tomentosa is most likely connected to the S60-1800 bp DNA fragment and RAPD markers. S60, therefore, can be used for selecting the gender of P. tomentosa. __________ Translated from Journal of Central South University of Forestry & Technology, 2008, 28(3): 80–83 [译自: 中南林业科技大学学报]     

A male-specific SCAR DNA marker and sex ratio of seedlings in salak (<Emphasis Type="Italic">Salacca zalacca</Emphasis> var. <Emphasis Type="Italic">zalacca</Emphasis>)

A male-specific SCAR DNA marker was developed using a RAPD DNA marker specific for male plants of Salacca zalacca var. zalacca (salak palm). The marker is 1579 bp long and has a GC content of 38.5 %. Its sequence contains 1 or 2 open reading frames, indicating the marker is probably a coding region. No highly similar sequences were found in a search of the GenBank database. Sexes were identified using the SCAR DNA marker for three kinds of seedlings grouped by the number of seeds per fruit (1, 2 or 3). The sex ratio of female to male did not differ significantly from 1:1 for the three kinds of seedlings, implying that the number of seeds per fruit is not a reliable index to identify the sex of a seedling.     

Individual leaf area estimations of a dioecious tropical tree species <Emphasis Type="Italic">Carpotroche brasiliensis</Emphasis> (Raddi) A. Gray,Achariaceae

Carpotroche brasiliensis is a dioecious tree species native of the Brazilian Atlantic rainforest. Due to medical and industrial use of the oil extracted from its seeds, C. brasiliensis has a great potential for cultivation as non-timber forest product in agroforestry systems. This study was conducted with the objective to analyze the leaf dimensions of male and female adult trees and seedlings of C. brasiliensis. Two hypotheses were tested: (a) leaf dimensions do not differ between male and female adult genotypes; and (b) it is possible to develop single regression models for predicting leaf area (LA) from dimensional variables encompassing male and female adult genotypes and seedlings. LA, leaf length (L) and maximum leaf width (W) were measured in leaves collected from seven male and seven female adult genotypes and three seedling lots. The feasibility of using a single model for leaves of males and females, and seedlings and adults, was tested by analysis of covariance (ANCOVA). The prediction errors (PE) for each of the regression models were calculated from the cross-validation method. The average values of L, W and LA were, respectively, 136, 142 and 457 % higher in adults than in seedlings, and the average values of leaf shapes (L:W) of seedlings were intermediate between the average values of L:W of adult males and females. The average values of L did not differ between adult males and females, but significant differences were observed between males and females for W, LA and L:W (both p < 0.01, nested ANOVA). The mean L:W values of adult males and females, and seedlings, indicate that leaf shape should be used as a criterion for sex differentiation in this species. It was not possible to develop single models encompassing adult males and females, and seedlings; but high accurate predictive models of LA from L × W measurements were developed for adult males (R² = 0.98, PE = 0.69, n = 350), adult females (R² = 0.98, PE = 0.01, n = 350), and seedlings (R² = 0.99, PE = 6.80, n = 150).     

Folk perception of sexual dimorphism,sex ratio,and spatial repartition: implications for population dynamics of <Emphasis Type="Italic">Sclerocarya birrea</Emphasis> [(A. Rich) Hochst] populations in Benin,West Africa

In Sub-Saharan Africa, indigenous fruit trees play vital roles in nutrition and food security particularly, in food shortage times. Sclerocarya birrea subsp. birrea, an indigenous dioecious fruit tree is such a resource with strong multipurpose use characteristics in semi-arid zones of West Africa. We assessed sex ratio, spatial distribution among male and female adult trees using second-order spatial statistics and assessed folk perception of dioecism among the natural populations in protected areas and surrounding agroforestry systems. A field survey showed that 55% of interviewees were aware of sex separation in the species. Some used bark appearance to make distinction between sexes, but this morphological criterion was not consistent with statistical results. The sex ratio did not deviate significantly from 0.5 in any of the districts or land use types. Bivariate spatial analysis with pair correlation function revealed no spatial association between male and female individuals. Moreover, a strict spatial segregation of sexes was not observed even though some individuals of the same sex could sometimes be found together. Results confirmed the functional dioecy of the species and showed that the species did not display any apparent sex-specific dimorphism outside the reproduction period or any apparent sex-specific requirement for environment conditions.     

不同沙棘品种抗旱性的比较

沙棘抗旱性是多因素作用的结果,如果只利用单因素/单项指标评价其抗逆性,则具有一定的片面性。本研究对干旱胁迫下4个沙棘品种的多项生理生化指标的变化进行比较分析,并通过主成分分析和综合评价发现:乡土中国沙棘(河北丰宁种源)品种的抗旱性最强,引进大果沙棘―乌兰格木品种的抗旱性最差,引进的4个沙棘品种抗旱能力强弱的排序为:丰宁(0.619)> 楚伊(0.445)> 向阳(0.390)> 乌兰格木(0.274)。净光合速率、蒸腾速率、气孔导度、叶水势、谷胱甘肽还原酶和脱落酸的含量可作为沙棘抗旱性的判定指标。随着干旱胁迫的加剧,与对照相比,4个引沙棘品种的净光合速率、蒸腾速率、气孔导度和叶水势均下降,而超氧化物歧化酶活性、细胞膜透性、谷胱甘肽还原酶和四大激素均上升,这说明干旱逆境胁迫影响了沙棘正常的生长发育过程,同时通过内在的生理生化指标的改变来增加其自身对逆境胁迫的抵抗能力。这些将为沙棘抗旱树种的筛选和进一步的杂交育种提供依据。     

RAPD analysis on genomic DNA of male and female plants ofAcer negundo L

Genomic DNAs were isolated from both male and female plants ofAcer negundo L., by modified CTAB method of Doyle and Doyle for plant genomic DNA isolation and consequently tested with RAPD technique. Some sex-related specific oxyribonucleic acid bands were amplified by a group of decamer oligonucleotide random primers. This indicated that some genetic marks related to sexes of the species were found, which laid a foundation for sapling sex identification ofAcer negundo L. Responsible editor: Chai Ruihai     

Floral display and breeding system of Jatropha curcas L.

Plant flowering and breeding characteristics are important for us to understand the reproduction of plant populations. In this paper, we studied the reproduction characteristics of Jatropha curcas in Yuanjiang County (23°36′N, 101°00′E), Yunnan Province. The plant produces flowers in dichasial inflorescences. Normally, the flowers are unisexual, and male and female flowers are produced in the same inflorescence. Only a few male flowers are produced in an inflorescence, and fruits are produced only through pollination between different flowers from the same or different plants. By the treatments of emasculation, bagging and artificial pollination in this experiment, there were few but same fruit set ratios when the inflorescences were emasculated, bagged, or bagged with net, except artificial pollination treatments, which showed that Jatropha curcas could produce fruit through apomixis but not wind pollination. When the inflorescences were unbagged, unemasculated and with free pollination treatments, or bagged, emascu- lated and with artificial cross-pollination treatments, or unbagged, emasculated and with free pollination treatments, there were many fruits produced. It showed that Jatropha curcas shows outcrossing, is self-compatible, and demanding for pollinators. Normally, the male flowers open first and a few flowers bloom in one day in a raceme. These flowers last a long time in bloom. However, a large number of female flowers open from the third to the fifth day, with some female flowers opening first in a few raceme. This shows a tendency to promote xenogamy and minimize geitonogamy.     

中国沙棘(♀)×蒙古沙棘(♂)杂种F1重要选种性状表型多样性与选优研究

基于远缘杂交技术路线,以中国沙棘优良单株MK-88-01、HF-88-05为母本,俄罗斯栽培种阿列依及蒙古大果沙棘乌兰格木子代优良雄株为父本,开展了中国沙棘与蒙古沙棘2个亚种间杂交育种研究。结果发现:杂种子代性状分化严重,棘刺数、百果质量、果实产量等最重要的几项经济指标的遗传分化程度最大。选育出3个优良杂种单株,其树高均显著高于父本,2年生枝棘刺数均为3个,与母本中国沙棘相比,棘刺数大量减少。优良杂种单株百果质量与单株产量分别达26.33 29.33 g、2.00 2.50 kg,比母本中国沙棘分别提高31.34%46.30%、66.67%108.33%。杂交子代具有单株生长量越大,其果实与种子表型指标就越小的变化规律,与母本中国沙棘体大果小、父本蒙古沙棘体小果大的表型特征相吻合。     

Short-term responses to salinity of seabuckthorn (Hippophae rhamnoides L.) seedlings in the extremely cold and saline Qinghai region of China

The investigation of the mechanisms of plant adaptation to stressor action is one of the leading directions of current biological studies. To understand the mechanism of salt tolerance of seabuckthorn (Hippophae rhamnoides L.) and identify its ability to cope with the salinity effect in the saline and extremely cold region of Qinghai, China, a test was conducted with two-year-old seedlings subjected to 0, 200, 400 and 600 mmol·L–1 NaCl solutions for 30 d. The results show that with an increase in salinity, the biomass of H. rhamnoides seedlings clearly decreased. Leaf water potential (Ψw) and relative water content (RWC) were significantly reduced under salinity, with severe water shortages appearing in leaves. At the same time, the total chlorophyll content declined markedly. When salinity increased and stress time prolonged, the net CO2 assimilation rate (A) significantly declined. Intercellular CO2 concentration (Ci) declined at first and was then followed by an increase over the stress time. We conclude that H. rhamnoides grown in the extremely cold and saline region of Qinghai has a certain resistance to salt, which can be planted at appropriate salinity levels.     

Evaluation of resistance in 14 soybean genotypes to <Emphasis Type="Italic">Tetranychus urticae</Emphasis> (Acari: Tetranychidae)

The effect of 14 soybean genotypes (Sahar, Sari, Williams, Tellar, Hill, Clark, Tms, Dpx, Zane, 032, 033, L₁₇, Ks3494 and I27) on life history and fecundity of two-spotted spider mite (TSSM), Tetranychus urticae Koch, was investigated. All experiments were conducted at 28 ± 1°C, 65 ± 5% r.h. and a photoperiod of L16:D8 h. The highest development time was 8.41 and 8.78 days for male and female on I27, and the lowest value of this period was obtained on Sahar and Ks3494 for male and female, respectively (7.11 and 7.60 days, respectively). The TSSM fecundity varied from 33.62 to 153.82 eggs per female, which was minimum on 032 and maximum on L₁₇. The comparison of TSSM biological parameters on different soybean genotypes and cluster analysis of these parameters demonstrated that Ks3494, 032, Dpx and Sahar were the most resistant genotypes to this pest. An antibiosis process could be, at least in part, the cause of this variation. Knowledge of the extent of susceptibility or resistance of genotypes and biology of a pest on a crop are fundamental components of integrated pest management (IPM) programs for any crop. Implication of these observations in the control of TSSM on soybean is discussed.     

银杏雌雄株过氧化物酶和过氧化氢酶活性差异研究

银杏 (Ginkgobiloba)是雌雄异株的树种 ,其雌雄株的生理差异较大 ;为此 ,从检测银杏叶片内过氧化物酶与过氧化氢酶的活性入手 ,找出差异性 ,进而对识别银杏的雌雄株提供依据     

Analysis of genetic relationship among Arbutus unedo L. genotypes using RAPD and SSR markers

The strawberry tree (Arbutus unedo L.) is an underutilized, drought tolerant, fire resistant species with a south western distribution in Europe, and with ecological and putative socio-economical impact in Portugal and Mediterranean countries. Our aim was to develop an appropriate set of molecular markers to enable genetic diversity to be assessed and to fingerprint Arbutus unedo genotypes for breeding and conservation purposes in Portugal. Twenty-seven trees from a broad geographic range were screened with 20 random amplified polymorphic DNA (RAPD primers) and 11 microsatellite markers (SSR). The RAPDs generated 124 bands, 57.3% of which were polymorphic, with an expected heterozygosity of 27%. We cross-amplified 11 SSR primers developed for Vaccinium spp., and 5 were found to be polymorphic in A. unedo, with 75% of expected heterozygosity, a number of alleles of 11.6, a null allele frequency of 7.6% and a polymorphic information content of 71%. Although the SSRs were more polymorphic and informative than the RAPDs, both markers displayed high genetic variability with the gathered data. No geographic pattern was observed in the genetic variation distribution based on both marker systems, and the lack of correlation between genetic and geographical matrices was confirmed by Mantel tests. Likely, no correlation was found between pairwise SSR and RAPD band-sharing matrices. These results and their implications on A. unedo breeding and conservation programs are discussed.     

Effects of water stress on water use efficiency and water balance components of <Emphasis Type="Italic">Hippophae rhamnoides</Emphasis> and <Emphasis Type="Italic">Caragana intermedia</Emphasis> in the soil–plant–atmosphere continuum

Hippophae rhamnoides (Sea buckthorn) and Caragana intermedia (Intermediate peashrub), which are nitrogen-fixing and perennial temperate shrubs, are extensively used in the agroforestry systems in the loess areas of China. In this study, artificially controlled water gradient experiments were carried out with both shrubs, based on four levels of water supply (normal precipitation, slight drought, drought, and extreme drought). The results showed significant impacts of drought on net photosynthesis rate, biomass accumulation, and biomass allocation in both species. Water use efficiency (WUE) varied with different species, scales, and water stress intensities. WUE at the leaf scale (WUEi) was highest under moderate water stress, while the WUE at the community scale (WUEb) decreased with increasing water stress. We observed alteration in the diel and seasonal transpiration of both species in response to water stress. The night-time transpiration accounted for a small but significant proportion of the water balance, and its importance tended to increase with increasing drought. Both species experienced water deficits under all treatments. Soil moisture of H. rhamnoides declined more severely than that of C. intermedia. The ratio of transpiration to evapotranspiration (T/ET) ranged from 50 to 80% for both species in the growing season. The T/ET and WUEi of H. rhamnoides were comparatively smaller under severe water stress but increased under moist conditions. Our data suggest that H. rhamnoides uses water resources more efficiently under favorable water conditions, and C. intermedia shows competitive advantages under drought conditions. Moreover, possible strategies to maintain water balance in the water-limited agroforestry systems are discussed.     

Adaptive genetic diversity and population structure of the “algarrobo” [<Emphasis Type="Italic">Prosopis chilensis</Emphasis> (Molina) Stuntz] analysed by RAPD and isozyme markers

The “algarrobo” [Prosopis chilensis (Molina) Stuntz] is a tree species that represents an important natural resource in arid and semi-arid regions of Argentina. In this paper, we analysed and compared the variability of 46 RAPD (Random Amplified Polymorphic DNA) loci with previous estimates obtained from 12 isozyme markers in nine Argentinean populations of P. chilensis representative of the whole range of this species in Argentina. We evaluated the population structure and the existence of genetic variants associated with environmental variables. Expected heterozygosity (H _e) estimated from RAPD varied significantly among populations and regions. Hierarchical analysis of genetic variability (AMOVA) showed that most (88.1%) of the total diversity occurs within populations, the component among populations within regions (9.3%) was intermediate, while the between-region component was the lowest (2.6%). All three variance components were highly significant. The MDS plot from pair-wise Φ _ST matrix was consistent with the highly significant among-region differentiation indicated by the AMOVA. All 12 variable isozyme loci and 26 out of 46 RAPD loci showed significant or highly significant association with at least one geographic/climatic variable according to the stepwise multiple regression analysis. These results imply that the genetic differentiation among populations is better explained by environmental or biogeographical grounds than by geographical distances, suggesting gametic disequilibrium with loci responsible for the adaptation to particular environmental conditions. The information from RAPD markers would provide a relevant criterion to preserve genetic diversity in programmes for conservation and rationale use of this species.     

Dynamics of Zn between soil and plant in Northeast Leymus chinensis grassland

A study was conducted to determine the dynamic of Zn content between soil and plant in the natural protection zone of Leymus chinensis grassland in Changling County (44°30′–44°45′N; 123°31′–124°10′E), Jilin Province, China. Results showed that the total Zn content was lower, available Zn content had a moderate level in the soil, and the plants was not lack of Zn. During the growing season, content of total Zn and available Zn in soil showed a down-trend distribution along the soil profile. Content of total Zn had a significantly positive correlation with that of the organic matter, but it was negatively correlated to soil pH. Monthly dynamic of the average content of total Zn showed a “V” type curve in the growing season from May to August, and July was the nadir. The trend of the average content of available Zn was similar to the content of total Zn, but was down after August; Zn content variation in the organs and litter of L. chinensis was great, with the order of root>rhizome >leaf>stem>litter. The ratio of available Zn content in A layer versus B layer was more than 2 times that of the total Zn, which indicated that the soil of A layer had higher enrichment capacity of available Zn. The enrichment of Zn in the root of L. chinensis was 44.17 times as that in the soil. The absorbing intensity of root had a significantly negative correlation with the activity of Zn in the soil (r=−0.8800, p<0.01). Biography: ZHOU Xiao-mei (1966–), female, Ph.D., associate professor of Jilin Normal University, Siping 136000, P.R. China.     

A male-specific SCAR DNA marker and sex ratio of seedlings in salak(Salacca zalacca var.zalacca)

A male-specific SCAR DNA marker was developed using a RAPD DNA marker specific for male plants of Salacca zalacca var. zalacca(salak palm). The marker is 1579 bp long and has a GC content of 38.5 %. Its sequence contains 1 or 2 open reading frames, indicating the marker is probably a coding region. No highly similar sequences were found in a search of the Gen Bank database.Sexes were identified using the SCAR DNA marker for three kinds of seedlings grouped by the number of seeds per fruit(1, 2 or 3). The sex ratio of female to male did not differ significantly from 1:1 for the three kinds of seedlings, implying that the number of seeds per fruit is not a reliable index to identify the sex of a seedling.     

Immunolocalization of an anionic peroxidase in differentiating poplar xylem

Peroxidases are the major candidate enzymes involved in dehydrogenative polymerization of monolignols. Peroxidases have the signal sequence at their N-terminus and this suggests that they are transported to extracellular spaces or developing cell walls. In this study, we focused on an anionic peroxidase isozyme encoded by prxA3a, which seems to be related to lignification. To investigate the localization of peroxidase in differentiating xylem cells of poplar (Populus sieboldii × Populus grandidentata), anti-PRX3 antibody was raised against the anionic peroxidase. Western blotting and peroxidase activity inhibition assay showed specificity of the antibody. Labeling by anti-PRX3 antibody was localized in vessels and fibers during the secondary wall formation and was observed along the plasma membrane beside the microtubules. The labeling was not seen in the cell wall, where localization of peroxidases was expected during lignification. The peroxidase isozyme, which is suggested to be involved in monolignol polymerization, is localized on the plasma membrane and its localization might be regulated by microtubules.     

华仁杏杂种鉴定及遗传变异分析

以华仁杏6个杂交组合为实验材料,利用SSR分子标记技术研究亲本与杂种扩增谱带的多态性,以甄别真假杂种。筛选出在亲本和杂种之间存在双亲互补带型的引物6对,除2个杂种无法鉴别外,其余品种均可鉴别为真杂种。另外亲缘关系和遗传变异分析结果表明,各个组合杂交后代表现出来的一致性较高,遗传多样性水平相差不大,但当父本选择X1时,母本选择H1或H3杂交后代差异比较显著。     

Induction of unreduced megaspores with high temperature during megasporogenesis in <Emphasis Type="Italic">Populus</Emphasis>

Introduction  

Triploid breeding is one of the most powerful approaches for improvement of the genus Populus L. Pollination with artificial unreduced (2n) pollen was inefficiency, owing to weak competition of 2n pollen. To induce 2n megaspores and improve the efficiency of triploid production, female buds of Populus pseudo-simonii × Populus nigra ‘Zheyin3#’ were exposed to high temperature during megasporogenesis.