根系隔离条件下的谷子亲缘识别

在根系隔离情况下, 通过研究邻株身份(亲缘株、非亲缘株、陌生株)及其与种植密度(高、低)和土壤养分水平(高、低)交互作用对谷子(Setaria italica)形态学特征和生物量分配的影响, 探索谷子地上部分是否能够识别亲缘邻株, 以及谷子的这种亲缘识别能力对环境因子如何响应。结果显示: 1)亲缘组谷子叶生物量分配显著降低, 茎秆显著增粗, 暗示着亲缘组谷子植株间减少竞争, 并增强对当地多风气候的适应。而非亲缘组谷子叶生物量分配显著增加, 表明非亲缘组谷子植株间竞争较强。2)与非亲缘组相比, 陌生组谷子种子生物量分配显著增加, 株高显著减少, 表明陌生组谷子植株通过不对称竞争(与邻株糜(Panicum miliaceum)植株相比, 株高显著增加), 进一步限制邻株(糜)生长, 从而增强竞争能力, 同时, 将更多的生物量投资于繁殖, 增加适合度。3)在高密度种植条件下, 谷子茎生物量和叶生物量分配在各邻株身份处理间无显著差异, 而在低密度种植条件下, 与非亲缘组相比, 亲缘组谷子茎生物量显著增加, 叶生物量分配显著减小; 随着种植间距的增大(种植密度减小), 亲缘组谷子叶生物量分配显著减少, 而非亲缘组和陌生组叶生物量分配在高、低种植密度条件下无显著差异。4)在低土壤养分条件下, 亲缘组和非亲缘组谷子叶生物量分配无显著差异, 前者穗长显著小于后者, 而在高土壤养分条件下, 亲缘组谷子叶生物量分配显著小于非亲缘组, 前者穗长显著大于后者。结果表明, 在根系隔离的情况下,谷子能够识别亲缘邻株, 且谷子地上部分竞争信号在亲缘识别过程中扮演重要角色。较低种植密度和较高土壤养分水平有利于谷子亲缘识别能力的表达。     

林地覆盖经营雷竹林叶片养分特征及其与土壤养分的关系

探讨了短期覆盖经营(覆盖1 a)、休养式覆盖经营(覆盖3 a 后休养3 a)、长期覆盖经营(覆盖6 a)和不覆盖雷竹林(CK)2年生立竹叶片养分含量、化学计量比和再吸收率及其与土壤养分的关系。结果表明：(1)短期和休养式覆盖经营促使雷竹叶片养分含量和再吸收率总体上提高,而长期覆盖经营对雷竹叶片 P 含量和N、K 再吸收率会产生较为明显的影响,叶片 P 含量、N 再吸收率显著升高,K 再吸收率降低;(2)短期和休养式覆盖经营对雷竹林土壤、叶片养分化学计量比影响不明显,但长期覆盖经营使雷竹林土壤、叶片 N∶P、K∶P 显著降低;(3)短期覆盖经营能增强雷竹林土壤养分与叶片的养分含量、化学计量比和养分再吸收率的相关性,但随覆盖经营年限的延长,相关性总体上呈减弱趋势;(4)土壤养分含量及其平衡关系对林地覆盖经营雷竹林叶片养分特征影响明显;(5)长期覆盖经营雷竹林土壤、叶片养分间相关性明显减弱,竹子吸收利用养分的能力下降,生产中应实行雷竹林休养式覆盖经营方式。研究结果为林地覆盖经营雷竹林的可持续发展提供了理论参考。     

吕梁山区3种人工林植被、凋落物生物量差异特征及其与土壤养分的关系

通过样地调查和土壤样品采集分析的方法,测定了山杨、油松和辽东栎3种人工林林下植被(灌木、草本)的活地被的生物量以及地表凋落物的生物量和土壤养分的总概况,并探讨了它们之间的相关性。结果表明:活地被生物量表现为油松2.354 7 t·hm~(-2)山杨2.078 5 t·hm~(-2)辽东栎1.137 3 t·hm~(-2),地表凋落物生物量山杨4.797 5 t·hm~(-2)辽东栎2.139 9 t·hm~(-2)油松0.525 0 t·hm~(-2);林下土壤分级指标结果:有机质、全磷均呈现4~5级标准,全氮为1~3级标准;林下土壤养分含量分析比较结果:有机质含量为山杨辽东栎油松,而全氮和全磷为山杨油松辽东栎;同时分析了土壤全量养分与各林分下活地被生物量、凋落物层生物量之间的相关性,结果表明:3种人工林的3种全量养分与活地被生物量、凋落物生物量均呈现极显著相关(P0.01),同时3种林分的土壤全量养分间相关性显著(P0.05),表现出良好的协同效应。     

黄河三角洲滨海滩涂不同密度柽柳林的土壤盐碱与养分特征

为探讨黄河三角洲滨海滩涂不同密度柽柳林的土壤盐碱和养分特征,明确不同密度柽柳林的“盐谷”及“肥岛”效应,以黄河三角洲山东省滨州市北海新区滨海滩涂的低密度（1100 株/hm2）、中密度（4100 株/hm2）和高密度（7100 株/hm2）柽柳林为研究对象,测定分析不同密度柽柳林及柽柳植株周边不同位置的土壤pH、电导率、速效氮、速效磷、速效钾、有机碳等指标。结果表明：（1）土壤电导率随林分密度增大表现为逐渐减小,在中、高密度柽柳林,土壤电导率分别比低密度降低28.39%、55.74%;随距离柽柳植株远近不同,中、高密度柽柳林土壤电导率表现为根部<冠幅中心<冠幅边缘<株间空地,即中、高密度柽柳林出现“盐谷”效应,而低密度林分未出现。（2）土壤速效氮、速效磷和有机碳含量随林分密度增大表现出先增大后减小,在中、高密度柽柳林,柽柳植株周边不同位置的速效氮、速效磷和有机碳含量存在显著差异（P<0.05）,表现为根部>冠幅中心>冠幅边缘>株间空地,而低密度柽柳林差异不显著（P>0.05）;即中、高密度柽柳林出现“肥岛”效应,而低密度林分未出现。（3）中密度柽柳林在养分含量、养分富集率方面高于高密度,在盐分富集率方面低于高密度,具有更强的“肥岛”、“盐谷”效应。（4）不同密度柽柳林以及柽柳植株周边不同位置的土壤pH差异均不显著（P>0.05）。林分密度显著影响土壤盐分及养分含量,中密度柽柳林具有显著提高土壤肥力的作用,高密度次之,而低密度较差。不同密度柽柳林的降盐作用表现为中、高密度较好,低密度较差。基于柽柳林改良土壤盐碱与养分的作用,建议黄河三角洲滨海滩涂柽柳合理的初植密度为4100 株/hm2。     

扎龙季节性湿草甸土壤养分和土壤微生物特性

以扎龙自然湿地典型季节性湿草甸为试验对象,研究了土壤微生物特性和土壤养分空间分布规律及其主要影响因子.结果表明:土壤养分、微生物群落数量、微生物量碳、氮均呈现明显的垂直分布特征;土壤酶活性的空间分布因受多种因素影响而表现复杂.逐步线性回归分析表明:土壤微生物生物量碳、氮均分别与β-葡萄糖苷酶、脲酶、磷酸酶显著相关(P<0.05);有机碳与放线菌数量、过氧化氢酶活性显著相关(P<0.05);速效钾、全氮、水解性氮、C/N分别与放线菌数量、细菌数量、β-葡萄糖苷酶活性、土壤微生物生物量氮显著相关(P<0.05);全P、pH与土壤微生物活性无显著相关关系(P>0.05).采用主成分分析构建了湿地土壤养分的评价模型及微生物学预测模型.     

作物种植前后土壤有机质及养分因子的空间变异分析

以作物土壤试验数据为基础,结合多年的农户调查数据,采用Moran's I指数分析、Pearson相关系数分析和Kriging插值3种地统计学方法,探讨了浙江省浦江县作物种植前后土壤有机质及氮磷钾等养分因子的空间演化规律。研究发现Moran's I指数分析证实随着区域范围的加大,各因子间自相关程度产生较大差异。这一点在Pearson相关系数分析中也得到证实,并在kriging插值图中直观表达。结果还表明:有机质和碱解氮的形成与水的关系较为密切,水源区两因子的含量较周边高,且会促进前者向后者转化。养分投入后,过多的养分在土壤中降解过程与区域自然环境条件的关系较密切。同一作物的农户养分投入在不同区域差异较大,不同作物的农户养分投入在区域内却存在量的相关。     

土壤养分库对缺苞箭竹叶片养分元素再分配的影响

研究了王朗自然保护区3个密度的缺苞箭竹群落的土壤养分库和叶片养分元素再分配能力的相互关系。结果表明,不同密度箭竹群落的土壤N、K贮量没有显著差异,土壤P贮量随着密度增加而显著减少（P〈0．01）,土壤Ca和Mg贮量则随着密度增加而增加。不同密度的箭竹叶片N和K的再分配能力没有显著差异,叶片P的再分配能力随着密度的增加而显著增加,Ca和Mg随着箭竹密度的增加在凋落叶中有显著积累的趋势。这表明,基于密度的箭竹叶片养分元素再分配能力与土壤养分库的大小密切相关,可能的机理过程是不同密度的箭竹在生长发育过程中改变了土壤养分库的大小,土壤养分库通过反馈机制导致箭竹叶片养分元素再分配能力的变化,体现了土壤与植被之间的互动关系。综合分析表明,P可能是限制缺苞箭竹生长发育的重要因子。     

种植密度对东北玉米农田土壤呼吸时空动态的影响

基于东北地区玉米生态系统土壤呼吸的观测数据,阐明了玉米常规密度种植和低密度种植土壤呼吸的日变化特征及其空间差异性,分析了温湿度对土壤呼吸的影响。结果表明:土壤呼吸日动态呈单峰型曲线,土壤呼吸日动态最大峰值出现的时间随测定位置不同而变化;玉米常规密度种植土壤呼吸速率最大峰值出现在12:00—15:00;低密度种植土壤呼吸速率最大峰值出现在11:00—16:00;在生态系统尺度上,测定位置距离玉米植株越远,土壤呼吸速率则越低;玉米常规密度种植土壤呼吸速率高于玉米低密度种植;测定位置不同,土壤呼吸速率与土壤温度、空气相对湿度的相关系数不同,均达到显著相关(P0.01),其中土壤呼吸速率与土壤温度呈正相关,与近地表的空气相对湿度呈负相关。     

蕨类植物碳氮磷化学计量特征及其与土壤养分的关系

为探讨蕨类植物碳氮磷化学计量特征与土壤养分的关系,对福建省亚热带森林林下芒萁和乌毛蕨地上部分和地下部分的碳、氮、磷(C、N、P)含量和0~10 cm和10~20 cm两个土层的养分含量进行了测定。结果表明,无论是芒萁还是乌毛蕨,地上部分的N、P含量均高于地下部分,而C含量则无显著差异,导致地上部分的C∶N和C∶P均低于地下部分。与乌毛蕨相比,芒萁地上部分的N、P含量更低,地上和地下部分的C含量、C∶N和C∶P以及N、P含量的变异系数和表型可塑性指数则更高,表明芒萁采取了较高的养分利用效率和"表现最大化"的策略,而乌毛蕨则选择了较低的养分利用效率和"表现维持"的方式。两种蕨类植物地上和地下部分的N含量与土壤N含量(0~20 cm)均无显著相关。芒萁两个部位的P含量则均与土壤P含量(0~10 cm和10~20 cm)呈显著正相关,乌毛蕨P含量总体上与土壤P含量的相关性不显著(除地下部分的P含量与10~20 cm土层的P含量呈弱的正相关外)。这表明芒萁具有作为亚热带森林土壤P库指示植物的潜力。     

海南岛北部木麻黄林凋落物与土壤养分、细根生物量的关系

通过对海口市桂林洋海岸木麻黄防护林地表凋落物进行持续清除处理,与保留凋落物层的对照样地进行比较实验,研究防护林凋落物-土壤养分-细根生物量三者之间的关系。结果表明:(1)处理样地与对照样地的年凋落物量分别是6.0162和5.9505t·hm-2,但无显著性差异。两种样地一年内凋落物量变化的时间格局较一致。凋落物组成均为小枝占比例最高,且小枝凋落物量月动态与凋落物总量月动态相似,杂物占比例次之,皮+枝占的比例最小;(2)N、P、K元素归还量的月动态变化在两样地中均较一致。两样地中小枝养分归还量的大小顺序为N>K>P;(3)处理样地在短时间无新鲜凋落物输入情况下,两样地的土壤养分含量无显著性差异;(4)两样地的细根生物量季节动态均呈现"单峰"特征,细根生物量在实验期间无显著性差异,但处理样地的细根生物量有随时间延长低于对照样地的趋势,清除凋落物的处理可能会引起细根生物量的减少。     

Inheritance of some marker genes in Setaria italica (L.) P. Beauv.

Summary A study on a series of genetic markers was run on five hybrids of foxtail millet, Setaria italica, and on one interspecific hybrid S. viridisxS. italica (S. viridis is the wild relative of S. italica). Seven enzymatic systems were investigated using starch gel electrophoresis (esterase, alcohol dehydrogenase, glutamate oxaloacetate transaminase, acid phosphatase, malate dehydrogenase, 6-phosphogluconate dehydrogenase, cathodic peroxidase). This genetic analysis of the 6 F2 has allowed us to define 12 polymorphic loci: Est-1, -2 and -3, Adh-1, Got-1 and -2, Acph-1, Mdh-1 and -2, Pgd-1 and -2, and Pox-1. All of them behaved like dimers, except Est-1 and Est-2 which showed monomeric structures. Two other markers were examined: waxy endosperm, which appeared to be controlled by one locus, and anthocyanic pigmentation of the collar, for which at least two loci are responsible. Studies of linkage carried out on three F2 showed two linkage groups: Mdh-1, Pox-1, Wx, Est-3, and a locus for collar colour, and Est-2, and one or two other loci of colouring.     

Geographical distribution and genetic analysis of phenol color reaction in foxtail millet,Setaria italica (L.) P. Beauv.

Summary Phenol color reaction was examined in a total of 376 strains of foxtail millet, Setaria italica (L.) P. Beauv., collected from different areas throughout Eurasia. Positive and negative phenotypes, and no intermediate type could be recognized by the phenol color reaction. Of 376 strains examined, 50 were positive, 319 were negative, five were mixtures of both phenotypes, and the coloration in two strains with blackish lemmata and paleae could not be distinguished. The strains that showed the positive phenotype of phenol color reaction were found in rather limited regions, while those with the negative phenotype occurred in almost all the regions. The positive phenotype occurred more frequently in the lower latitudinal regions of Asia. Genetic analysis of the F₁ and F₂ generations between the two phenotypes showed that the phenol color reaction is controlled by a single gene, and that the positive phenotype is dominant.Contribution No. 28 from the Plant Germ-plasm Institute, Faculty of Agriculture, Kyoto University, Kyoto (Japan)     

In vitro selection and characterization of Ni-tolerant callus lines of Setaria italica L

Nickel tolerant callus lines of Setaria italica L. were developed from callus cultures grown on MS medium supplemented with 0.5 mg·dm⁻³ kinetin+2.0 mg·dm⁻³ 2,4-D+2.0 mg·dm⁻³ Ni⁺². Standard growth parameters such as callus fresh and dry weight, growth tolerance index were used as indicators of nickel toxicity. Measurements as early as 2 weeks after the beginning of the treatments did not yield consistent results. However, growth tolerance index at 4, and 8 weeks after the beginning of treatments yielded significant differences among the non-tolerant and tolerant calli. The tolerant calli has enhanced growth at 2.0 mg·dm⁻³ Ni⁺² while non-tolerant calli showed a reverse trend in growth in the presence of 2.0–2.5 mg·dm⁻³ of nickel. The tolerant calli differentiated into mass of embryogenic calli within 4 weeks of culture which could be maintained for prolonged period without loss of regenerative capacity.     

植物根系的身份识别能力、作用及影响机制

自然生境中有些植物的繁殖体传播距离有限, 这类植物更有可能与其亲缘相近的植株相邻。植物个体能否识别邻株的身份并做出相应的反应, 会对植物间的相互作用产生重要影响。亲缘选择理论预测亲缘相近的植物间可以通过亲缘识别和选择作用, 有效地削弱彼此间的干扰和竞争, 从而增加适合度。对植物通过根系进行自我/ 非我和亲缘识别能力、作用及其影响机制进行了综述, 同时指出了当前研究中存在的一些疑点和亟待解决的问题, 对植物身份识别研究的发展方向进行了展望。     

Variation,geographical distribution and genetical analysis of esterase isozymes in foxtail millet,Setaria italica (L.) P. Beauv.

Summary The esterase isozymes of 432 strains of foxtail millet, Setaria italica (L.) P. Beauv., collected from different areas throughout Eurasia, were investigated by gel isoelectric focusing. Five phenotypes were recognized, based on the combination of five major activity bands. Cross experiments among different phenotypes revealed these isozymes to be controlled by two codominant alleles and a null allele on the locus, Est-1, and three codominant alleles on another independent locus, Est-2. On locus Est-1, 388 strains had Est-1 ^a, 41 had Est-1 ^b and three had Est-1 ^null alleles. Est-1 ^a was widely distributed throughout Eurasia, while the distribution of Est-1 ^b and Est-1 ^null was distinctly restricted. On locus Est-2, 417 strains had Est-2 ^a, nine had Est-2 ^b and six had Est-2 ^c alleles. Est-2 ^a was widely distributed throughout Asia to Czechoslovakia, but was not detected in the western part of Europe. Est-2 ^b was found in all of the strains from the western part of Europe and in one of the Indian strains. Est-2 ^c was rarely found in Japan and China. The distribution of Est-2 ^a and -2 ^b might indicate some degree of phylogenetic differentiation between the Asian and the European strains. Polymorphism in both loci was observed only in Chinese strains.Contribution No. 30 from the Plant Germ-plasm Institute, Faculty of Agriculture, Kyoto University, Kyoto, Japan     

5种相思树和尾巨桉人工林土壤养分和酶活性特征

为揭示固氮树种土壤养分转化的酶学机制,对固氮树种[厚荚相思(Acacia crassicarpa)、黑木相思(A. melanoxylon)、卷荚相思(A.cincinnata)、大叶相思(A.auriculiformis)和马占相思(A.mangium)]及非固氮树种尾巨桉(Eucalyptusurophylla×E.grandis)人工林的土壤养分含量、酶活性及其相关性进行研究。结果表明,相思林40～60cm土层的pH均高于尾巨桉林;5种相思林土壤各土层的TP、TK含量均低于尾巨桉林,而20～40 cm土层的TC、TN含量均高于尾巨桉林,黑木相思林和马占相思林各土层的有效养分均显著高于尾巨桉林(P0.05)。0～10 cm土层中,相思林的土壤酸性磷酸酶和纤维素酶活性均高于尾巨桉林,大叶相思林的土壤脲酶、蔗糖酶、纤维素酶和芳基硫酸酯酶活性显著高于尾巨桉林(P0.05),卷荚相思林的土壤脲酶、纤维素酶、几丁质酶和淀粉酶活性显著高于尾巨桉林(P0.05)。相关分析结果表明,土壤脲酶、蔗糖酶和几丁质酶活性与AP显著负相关(P0.05),蔗糖酶和纤维素酶活性与NH4+-N显著负相关(P 0.05),脲酶、纤维素酶、芳基硫酸酯酶与土壤TK显著负相关(P0.05),几丁质酶活性与TN含量呈显著正相关(P0.05),土壤淀粉酶活性与NH4+-N呈显著正相关(P 0.05),过氧化氢酶活性与土壤TK含量呈显著正相关。可见,与尾巨桉人工林相比,在我国南方退化山地引种相思树可提高土壤关键酶的活性,对土壤有效养分具有明显改良作用,有利于退化地土壤的生态修复及人工林长期生产力的维持。     

Inheritance of some Mendelian factors in intra- and interspecific crosses between Setaria italica and Setaria viridis

Summary The inheritance of seed coat color, pericarp color, polyphenoloxidase activity and bristle, glume, collar, and leaf-base anthocyanic colorations was investigated using intra- and interspecific crosses between Setaria italica and S. viridis. The results were compared to inheritance results obtained by previous authors. In most cases, the inheritance is simple (one or two loci) and data from different crosses (intra- and interspecific) and from different authors can be compared. Two sets of two characters were found to share common loci: the polyphenoloxidase locus is one of the loci responsible for seed coat color, and bristle and glume color are determined by the same two loci. The evolutionary significance of these results is discussed.     

谷子产量和品质相关性状的杂种优势及遗传特性分析

为了解谷子(Setaria italica)两系杂交后代的产量和品质相关性状的杂种优势,以3个高度雄性不育系为母本(A1、A2和A3),6个抗除草剂恢复系为父本(R1、R2、R3、R4、R5和R6),采用不完全双列杂交(NCⅡ)设计配制了18个组合,分析组合的株高、粒重和蛋白含量等11个性状的配合力和杂种优势特性.结果...     

Albendazole induces apoptosis in adults and microfilariae of Setaria cervi

Setaria cervi, a filarial nematode of cattle, inhabits in the peritoneal cavity and has been used as a suitable model for screening antifilarial agents. Albendazole (ABZ), a tubulin-disrupting benzimidazole (BZ) and a potent microfilaricide binds to β-tubulin, is causing structural impairment of cytoskeleton and worm death. Our present study has revealed that exposure of microfilaria (Mf) and adult to gradually increasing concentration of ABZ leads to a dose-dependent gradual impairment of their motility followed by early death in vitro. We found extreme cellular disturbances in ABZ-treated worms characterized by nucleosomal DNA laddering and chromatin condensation. However, in the treated Mf no nucleosomal DNA laddering was found although presence of TUNEL reactive DNA was evident, thus indicating an apoptotic pathway independent of DNA fragmentation. We present data from molecular studies to provide evidence for ABZ-induced apoptosis in Mf and adult worms of S. cervi.