[SSR analysis on stress effect of transgenic hybrid poplar 741 on Clostera anachoreta (Fabricius) (Lepidoptera: Notodontidae)]. / é¶æ ‡æ˜†è™«æ¨æ‰‡èˆŸè›¾å¯¹è½¬BtåŸºå› 741杨胁迫效应的SSR分析.

The genetic differentiation of the experimental population of Clostera anachoreta fed on different resistant transgenic 741 poplar leaves was analyzed by SSR molecular marker technique to investigate stress effect of transgenic poplar Bt gene as food on target insect. The experimental population of C. anachoreta fed on transgenic 741 poplar high resistant strains 'Pb29', medium resis-tant strains 'Pb17' and non-transgenic poplar (CK), and the screened ten pairs of SSR primers were used. The results showed that 76 alleles were observed in ten pairs of primers. The average allele was 7.6, the average effective number of alleles was 2.2, the average observed heterozygosity was 0.5167, the average expected heterozygosity was 0.5167, and the average percentage of polymorphic loci was 96.7%. The genetic diversity level of C. anachoreta experimental population fed on transgenic poplar 741 was significantly higher than that fed on non-transgenic populations, and C. anachoreta fed on high resistance had the lowest genetic similarity with CK samples, which showed an increasing trend of the genetic diversity of the experimental population fed on transgenic Bt poplar. It was thus clear that transgenic hybrid poplar 741 had stress effects on genetic differentiation of C. anachoreta experimental population by SSR.

Simultaneous Determination of Salicylic Acid, Jasmonic Acid, Methyl Salicylate, and Methyl Jasmonate from Ulmus pumila Leaves by GC-MS.

Salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate are important phytohormones and defensive signaling compounds, so it is of great importance to determine their levels rapidly and accurately. The study uses Ulmus pumila leaves infected by Tetraneura akinire Sasaki at different stages as materials; after extraction with 80% methanol and ethyl acetate and purification with primary secondary amine (PSA) and graphitized carbon blacks (GCB), the contents of signal compounds salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate were determined by GC-MS. The results showed that the level of salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate increased remarkably in U. pumila once infected by T. akinire Sasaki, but the maximums of these four compounds occurred at different times. Salicylic acid level reached the highest at the early stage, and jasmonic acid level went to the maximum in the middle stage; by contrast, change of content of methyl salicylate and methyl jasmonate was the quite opposite.

[Characteristics of soil seed banks in logging gaps of forests at different succession stages in Changbai Mountains].

An investigation was made on the soil seed banks in the logging gaps of Populus davidiana--Betula platyphylla secondary forest, secondary broad-leaved forest, and broad-leaved Korean pine mixed forest at their different succession stages in Changbai Mountains. Among the test forests, secondary broad-leaved forest had the highest individual density (652 ind x m(-2)) in its soil seed bank. With the succession of forest community, the diversity and uniformity of soil seed bank increased, but the dominance decreased. The seed density of climax species such as Pinus koraiensis, Abies nephrolepis, and Acer mono increased, whereas that of Maackia amurensis and Fraxinus mandshurica decreased. Moreover, the similarity in species composition between soil seed bank and the seedlings within logging gaps became higher. The individual density and similarity between soil seed bank and the seedlings in non-logging gaps were similar to those in logging gaps. All of these indicated that soil seed bank provided rich seed resources for forest recovery and succession, and the influence of soil seed bank on seedlings regeneration increased with the succession.

[Arthropod communities in jujube-grain intercropping system: composition and time series dynamics].

In order to reveal the correlations between the arthropod communities in two sub-systems (jujube yard and grain field) of jujube-grain intercropping system, an investigation was conducted on the composition and time series dynamics of the communities in the two sub-systems. A total of 14 936 arthropod individuals belonging to 14 orders and 96 families were found, among which, 5992 individuals of 14 orders and 82 families were in jujube yard and 8971 of 14 orders and 80 families were in grain field, and some differences were observed in the arthropod community structure between the two sub-systems. The time series dynamics of the arthropod communities could be divided into four periods, according to the optimal cut-apart of time series, i.e., decline period in grain field sub-system, species number increase period in whole system, steady period in whole system, and decline period in whole system. The primary natural enemies in the system showed a characteristic of transferring between the two sub-systems in the four periods, and the parasitical natural enemies in a sub-system could impact the pest insects in another sub-system. The species transferring and mutual effect of the arthropod communities between the two sub-systems could benefit the stability of the jujube-grain intercropping system, and the capability of the system in controlling pest insects.