Nash Equilibrium Mechanic of Environmental and Human Capital

The externality of surrounding is introduced into the 2-capital of economical increasing models, which includes human factors, to explore the influences of circumstances contradiction on the human capital formation. The normal and special nash equilibrium of environmental and human capital is presented through a limited boundary model of overlapping generations. The character of equilibrium trail and its economical meaning are examined. The study on the model shows that laissez faire economy will be either stagnant,growing,or collapsing in the long-run,depending on the returns of the learning technology with respect to the two kinds of capital,the initial state of economy,and the relative price of the environmental and consumption goods.     

不同供磷水平小麦苗期根系特征与其相对产量的关系

研究了缺磷条件下不同基因型小麦苗期根系形态学及生理学适应特征 ,结果表明 :在缺磷环境中 ,小麦根轴数量和侧根长度明显减小 ,同化物向根部的分配比例增加 ,根轴长度、侧根数量和根系长度等均是显著提高。供试基因型小麦的根轴数量及其长度的差异在每个供磷水平及不同供磷水平之间均是显著的 ,说明这两种性状的差异是由基因型和环境因素共同决定的 ;而侧根特征的差异只在不同供磷水平之间是显著的 ,表明侧根性状主要是受环境因素控制的。对 6种基因型小麦的研究表明 ,高磷水平的小麦种子根的生长角度明显低于低磷处理的小麦 ,根角之间存在着显著的基因型差异。在缺磷条件下 ,6种基因型小麦完整根系分泌的酸性磷酸酶活性、根轴数量、根轴长度、根生长角度和根系长度之间均存在着显著的基因型差异。相关分析表明 ,缺磷条件下的小麦苗期根系形态指标和根系分泌的酸性磷酸酶活性的交互作用与小麦的相对产量之间具有显著的线性关系 ,这种关系说明以上 5种性状均可作为早期有效地筛选磷高效小麦品种的指标     

桃铁离子吸收动力学研究

以毛桃幼苗为试材，对不同铁形态、pH值和盐胁迫条件下铁离子吸收动力学特性进行了研究。结果表明，pH是影响铁吸收的主要因素，不同铁形态的有效性随pH的变化而变化；pH和铁形态影响桃铁离子吸收动力学参数Km和Imax；NaCI胁迫对盐敏感性植物（桃）铁吸收特性的影响，可能与质膜透性、载体系统活性以及介质中有效铁含量有关。     

self-(in)compatibility almond genotypes: A review

To compile self-(in)compatibility almond genotypes, a review of 133 commercial cultivars of wide geographical origin was made. The information gathered from own and mainly published work will be useful for both grower's cultivar choice when planting and for breeder's cross design when planning. The almond S genotypes compiled were identified using five different methods: biological (pollination tests in the field and in the laboratory) and molecular (RNases, PCR and sequencing). In most cases, genotypes were assigned after combining more than one technique. Cultivars were classified into three categories: self-incompatible (99), self-compatible (16) and doubtful self-incompatible (18). The database is divided in 9 fields (name, origin, parentage, obtention year (crossing, selection or release), S genotype, technique used, reference, consensus genotype, and cross incompatibility group). A study of the 27 S alleles already identified and their geographical distribution within the cultivated almond is also presented. The study was divided into cultivars of known and unknown parentage and the distribution of S alleles frequencies was uneven among the 133 cultivars. S allele frequencies are related to geographical origin. Some alleles (S ₁, S ₅, S ₇ and S ₈) are more frequently observed than the others among cultivars of both known and unknown parentage. In the cultivated almond, the S f allele is only found in the Puglia region, Italy. The S _f frequency is three times higher in cultivars released from breeding programmes than in cultivars selected by growers. From the 351 resulting possible genotypes by combination of the 27 S alleles identified only 20 CIG (0-XIX) have been established, which represents a small fraction of the whole genetic diversity of this polymorphic gene in almond.     

Susceptibility to sharka (Plum pox virus) in Prunus mandshurica×P. armeniaca seedlings

Prunus mandshurica [(Maxim.) Koehne] from Central Asia is a species related to apricot and grown in China and Mongolia. This species has been used in apricot breeding as a source of frost resistance. In addition, P. mandshurica has been suggested as the possible origin of some North American apricot cultivars resistant to sharka (Plum pox virus, PPV). The aim of this work was to transmit the resistance to PPV from P. mandshurica to the Spanish apricot cultivar ‘Currot’ by traditional crossing. The resistance to a Dideron PPV isolate of the descendants of P. mandshuricaבCurrot’ and their progenitors was evaluated under controlled conditions in a greenhouse. The results showed the susceptibility of both, the progenitors and the offspring to PPV, as being much higher than in other apricot seedlings. The results showed that the P. mandshurica accession studied is not a good progenitor in breeding apricot for PPV resistance, but just the opposite. The possible role of P. mandshurica as a source of resistance in apricot resistant cultivars is questioned.     

氮磷钾肥施用量对稻米直链淀粉含量和淀粉粘滞特性的影响

通过盆栽和大田试验,研究了N、P、K肥对稻米直链淀粉含量和淀粉粘滞特性的影响。结果表明,N肥施用量增加,直链淀粉含量、最高粘度和崩解值下降,消碱值和回复值上升。增施P肥对直链淀粉含量影响不明显,对最高粘度、崩解值、消碱值和回复值影响效用,供试品种间变化趋势存在差异。K肥施用量增加,各品种均表现出直链淀粉含量、最高粘度、崩解值上升趋势,消碱值和回复值呈下降趋势。对NPK肥,不同品种反应程度不同,品种与N、P、K之间,N、P、K三者之间都存在互作效用。减少N肥用量,适量增施K肥有利于稻米食味品质的提高。     

长期施肥对红壤磷组分及活性酸的影响

以12年的红壤长期肥力监测定位试验不同处理土壤为材料,研究了连续施肥对土壤磷组分、土壤对磷吸附解吸、土壤活性酸铝的影响。连续施用化学磷肥和化肥加有机肥,均可提高土壤全磷、无机磷数量。施用有机肥料,土壤中的磷以Ca-P和Al-P积累为主要表现形式,化学磷肥的施用能够提高土壤的全磷,并以Al-P增幅为最大,在所有处理中均表现为土壤O-P相对稳定。有机肥料处理土壤对外源磷的吸附强度明显少于施用化学磷肥和不施用磷肥的处理,有机肥料能够显著提高吸附磷的再利用,在NPKM处理中解吸磷占吸附磷的47.72%,M处理中占42.89%,其它处理中解吸磷占吸附磷数量一般少于8%。MNPK、M处理的PFI为2.51、2.69比N、NP处理4.53、4.37明显降低。在红壤旱地长期施用化学肥料,土壤交换性酸铝成倍增加,土壤酸化严重;施用有机肥料、有机肥料与化学肥料配合施用,土壤交换酸铝表现稳定。     

An extended interspecific gene pool available to peach and almond breeding as characterized using simple sequence repeat (SSR) markers

Genetic diversity, as revealed by eighteenSimple Sequence Repeat (SSR) markers inthirty almond [P. dulcis (Mill.) D.A.Webb], twenty fresh-market peach [Prunus persica (L.), Basch], fifteenprocessing clingstone peach cultivars, andten rootstocks, established the geneticrelatedness among cultivars andcharacterized the variation within andbetween species. One accession each of thewild Prunus species, P.davidiana [(Carriere) Franch] and P.webbii [(Spach.) Vieh.], was included inthe analysis. The number of presumedalleles revealed by the SSR analysis rangedfrom one to six in peach whereas almondcultivars showed a range of three to nine.Peach cultivars clustered into ten groups,which are in general agreement withdocumented origin. Most processingclingstone peach cultivars clusteredseparately from fresh-market freestonecultivars supporting a distinct origin. Twomajor clusters were observed in almond withone containing California cultivars and theother containing European cultivars and theimportant California cultivar Mission.Results establish the value of SSR markersfor distinguishing different geneticlineages and characterize an extensive andlargely unexploited inter-species gene poolavailable to peach and almond breedingprograms.     

The Tripartite Symbiosis Formed by Indigenous Arbuscular Mycorrhizal Fungi, Bradyrhizobium japonicum and Soya Bean Under Field Conditions

The tripartite symbiosis formed by indigenous arbuscular mycorrhizal fungi (AMF), Bradyrhizobium japonicum (Kirchner) Jordan and soya bean (Glycine max L. Merr. cv. Evans) was investigated under field conditions to test the hypotheses that: (i) the tripartite symbiosis enhances nodulation and nodule activity; and (ii) its establishment does not rely on improved phosphorus (P) uptake through the fungal partner. Soil tillage was used to produce treatments with contrasting AMF colonization potentials while the amount of B. japonicum inoculum was kept constant. Nodulation, AMF colonization and the P and nitrogen (N) nutrition of plants were evaluated at 10 and 51 (full‐bloom) days after emergence. N₂ fixation was estimated by the difference method and by the isotopic dilution method. At the early stage of plant growth, AMF hyphal colonization and nodulation were, respectively, 16 % and 33 % greater in plants from untilled than from rototilled soil. The establishment of the tripartite symbiosis was observed under field conditions, and factors other than P nutrition were critical to its formation. However, the tripartite symbiosis did not promote N₂ fixation under the high soil P conditions of this study.     

杂交稻野败胞质对稻瘟病菌、白叶枯病菌感病性的研究

选用3个水稻野败胞质不育系及相应的保持系,3个恢复系及它们相应的野败胞质代换系,这些不育系、保持系同恢复系配组的18个 F_1,分别在秧苗期接种属我国7个稻瘟病生理小种群的21个菌株;在成株期接种15个白叶枯病菌株。结果表明,野败胞质较之正常胞质表现对这两种病菌感病稍轻;这种差异在多数保持系的基因型背景下达到显著水准,