Fifty-eight actinomycetes were isolated from surface-sterilized tomato (Lycopersicon esculentum) roots and 43 isolates were screened for herbicidal activities. Isolate S5 was found to have potent herbicidal activity against germination of wheat (Triticum aestivum L.), mung bean (Phaseolus radiatus L.) and grass (Paspalum notatum and Cynodon dactylon) seeds. But the metabolites of isolate S5 showed no influence on the growth of wheat seedlings. The S5 strain was identified as Streptomyces lavendulae var. glaucescens based on its morphological characteristics and physiological properties. The highest herbicidal activity was observed when 2% inocula were applied into S medium (containing 1% glucose, 0.3% beef extract and pH 7.0) and incubated at 25°C on a rotary shaker (160 rpm).

The cloning and sequencing of two specific molecular markers linked to grape (Vitis vinifera) seedless gene indicated that the full lengths of the markers, 39970524-5-564 (GenBank accession number: AY327513) and 39970524-6-1538 (GenBank accession number: AY327514), were 564 bp and 1538 bp, respectively. The restriction sites of sequences 39970524-5-564 and 39970524-6-1538 were analysed with Wingene231 software. The results indicated that there were 29 and 130 restriction sites in 39970524-5-564 and 39970524-6-1538, respectively, digested by restriction enzymes with recognition sites of six or more than six bases. There was no cleavage site in 39970524-5-564 and there was one site at 135 bp of 39970524-6-1538 when these two markers were digested by EcoRI. Both markers can not be digested by HindIII. Therefore, the full length of 39970524-5-564 and of the two bands of 39970524-6-1538 (1400 bp and 135 bp) could be cut out from the pGEMR-T Easy Vector by EcoRI. The labelled DNA of 39970524-5-564, used as a probe for Southern blotting with genomic DNA from Red Globe, Flame Seedless, Thompson Seedless, four seedless hybrids and three seeded hybrids, showed a unique hybrid band present in all seedless individuals, but absent in all seeded individuals. It was further indicated that the specific marker 39970524-5-564 was derived from the genome of seedless grapes.

In vitro development of goat embryos obtained by fertilizing oocytes using intracytoplasmic sperm injection (ICSI) was investigated. The results showed that the blastocyst rate was significantly higher (P<0.05) when the embryos were co-cultured with granular cells (GCs) in media CR1aa supplemented with 10% bovine follicular fluid (BFF) (22.2%) than with 5% (13.1%) and 15% BFF (2.7%). When embryos were co-cultured with GCs in SOFaa media, the highest blastocyst rate was obtained from supplementation with 10% BFF (25.1%), which was significantly different from 5% (12.9%) and 15% BFF (3.0%) groups. When 10% BFF and fetus bovine serum (FBS) were added into CR1aa or SOFaa media, the goat ICSI blastocyst rates were 22.6 and 26.9% or 5.8 and 6.1% respectively. These results suggest that both CR1aa and SOFaa could be used as culture media for goat ICSI embryos, 10% BFF could significantly increase the blastocyst rate and BFF was more efficient than FBS for the early in vitro development of goat ICSI embryos.

An amplification fragment length polymorphism (AFLP) molecular linkage map with a relatively high density for location of quantitative trait loci (QTLs) controlling the quantitative traits of silkworm (Bombyx mori) cocoons, was constructed using 91 individuals of the F2 generation. Among the 692 effective loci, 550 were allocated to subgroups a and b, of which 21 linkage groups in subgroup a had 233 molecular markers and 28 linkage groups in subgroup b had 317 markers. The number of markers on each linkage group in subgroups a and b ranged from 4 to 43 and 3 to 35, respectively. The total length of linkage groups for subgroup a was 1868.10 cM, and 2677.50 cM for subgroup b. The length of linkage group varied from 22.3 to 424.3 cM in subgroup a and from 2.4 to 366.5 cM in subgroup b. The average variation in the distance between markers was 3.39–17.43 cM in subgroup a and 0.8–26.96 cM in subgroup b. The average distance between the markers was 8.81 cM in subgroup a and 9.26 cM in subgroup b. There were 14 linkage groups, with an average distance below 10 cM, in subgroup a and 18 linkage groups in subgroup b. There were seven linkage groups with an average distance between 10 and 20 cM in subgroup a and ten linkage groups in subgroup b. Each linkage group in subgroup a had 11.1 loci on average, while there were 11.31 loci on each linkage group on average in subgroup b. The mean length for linkage groups in subgroups a and b was 89 and 95.6 cM, respectively. The total average length for both a and b subgroups was 2272.8, and 9.06 cM for the average marker distance, fulfilling the basic known requirements for locating QTLs.

Using four oilseed rape (Brassica napus L.) F1 hybrids (7039, 7040, 282 and 5102) as donor plants for microspore culture, the experiment was conducted to select glyphosate- and haloxyfop-resistant embryos through application of these substances to the cultural media with microspore-derived embryos in vitro. Genotypes 7039 and 7040 were used to select glyphosate-resistant regenerated plants, and genotypes 282 and 5102 to select haloxyfop-resistant plants. The embryos at cotyledonary stage were grown on glyphosate- and haloxyfop-containing MS-2 medium for 2 weeks. The non-resistant embryos collapsed after a short time, while the resistant ones turned green and survived for 2 weeks. Transferred into the normal MS-2 medium for further plant regeneration, the regenerated plants from green embryos showed tolerance to 0.25% sprayed glyphosate, indicating the effectiveness and reliability of this in vitro selection method. When the regenerated plants selected from 0.02% haloxyfop were sprayed with 0.05% haloxyfop, most of them grew well; however, the survival rate of the regenerated plants from 0.01% haloxyfop-containing medium was lower. The present experiment indicates that the use of 0.02% haloxyfop in the selection of haloxyfop-resistant plants was more promising than that of 0.01%. The chromosome doubling efficiency of regenerated plants reached 34% and 52% after being treated with 170 mg/l colchicine for 20 and 30 h, respectively.

The bovine interferon-γ gene cloned from total RNA of peripheral blood lymphocytes stimulated with concanavalin A (ConA), using the reverse transcriptase-polymerase chain reaction (RT-PCR), was cloned into pGEM T-easy vector and sequenced. The mature peptide without signal peptide was then subcloned and constructed into the expression plasmids pET28a/BoIFN-γ and pPICZα/BoIFN-γ, respectively. The former was highly expressed, induced by isopropyl β-d-thiogalactoside (IPTG), in Escherichia coli BL21, with 30% of bacterial proteins in inclusion bodies. The latter was expressed in Pichia pastoris GS115 with methanol induction. The expressed products were secreted directly into cultural supernatant at concentrations of 1.0 g/l. The same recombinant proteins had antiviral activities 10 times higher in an MDBK (Madan-Darby bovine kidney)/VSV (Vesicular stomatitis virus) cell line than in a CEF (chicken embryo fibroblast)/VSV) cell line, and the antiviral activities expressed in P. pastoris were higher than those expressed in E. coli in the same cell line.

In order to reveal the molecular basis of heterosis, Large White (LW), an introduced European pig breed, and Meishan (MS), a Chinese indigenous pig breed, were selected to hybridize directly and reciprocally in the present experiment. mRNA differential display (DD) technique was performed to identify genes that were differentially expressed in the backfat tissues of hybrids (LW×MS, MS×LW) and purebred (LW×LW, MS×MS) pigs. The ten anchor primers in combination with ten arbitrary primers (100 sets in total) were used and nearly 1500 reproducible bands were observed in polyacrylamide gels. The 40 differentially displayed bands were selected for cloning and sequencing. Thirty-six out of 40 expressed sequence tags (ESTs) proved to be novel and the sequences were submitted to GenBank (accession No. CV507051-CV507087); the other four showed similarity to known genes published in GenBank. Three among 36 novel ESTs were chosen for further identification with semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR). The result showed that two ESTs were differentially expressed, and the third showed no obvious difference between hybrids and purebreds. In order to reduce the percentage of false-positive DD, RNA pools of four types of pigs were constructed, by mixing samples from six pigs of the same genotype, and subjected to DD. Stringent annealing temperature was applied and only bands that could be repeated in duplicate PCR were used for further study. The results showed that the expression pattern of these 36 ESTs differed among the four genotypes of pigs, suggesting that the genes corresponding to these differentially expressed ESTs might be related to the heterosis occurring in fat tissue.

Genetically modified organisms (GMOs) containing anti-herbicide genes account for more than 75% of all GMO and the proportion is increasing. The polymerase chain reaction (PCR) method has proved to be an invaluable tool for the specific and sensitive detection of genetically modified material in foodstuffs and PCR screening for the presence of transgenic components in food is becoming a routine method in modern food analysis. In this study, the five kinds of the anti-herbicide genes (bar, pat, cp4-epsps1, cp4epsps2 and gox) were examined by PCR in four kinds of genetically modified crops (soy, maize, cotton and rape). Results indicate that the method was sensitive, specific and credible, and that all genetically modified and approved crops containing the anti-herbicide genes can be examined by this method.

Increasing the growth rate is especially important for low-quality wood applications, so this has become an important goal in poplar breeding. The present study describes the transfer of Vitreoscilla haemoglobin (VHb) gene (vgb) driven by constitutive promoters, by Agrobacterium tumefaciens into poplar (Populus alba×P. glandulosa). From about 450 leaf discs used for transformation, 60 Kan-resistant plants were obtained, and 52 proved to be true transgenic plants. The transgenic nature of these plants was confirmed by polymerase chain reaction (PCR) amplification and Southern dot blot hybridization. The expression of vgb gene in transgenic plants was confirmed by reverse transcriptase-PCR (RT-PCR). The performance of the transgenic lines was evaluated during the first year of growth in a greenhouse. These plants showed no significant stable morphological differences from the untransformed plants. Among them, three vgb-transgenic lines exhibited noticeably higher growth rates in terms of height and diameter.

To analyse the influence of genetically modified (GM) rice (Oryza sativa) containing the exogenous choline oxidase (codA) gene on physiological metabolism and genetic horizontal transformation in the fed rats, the animals were divided randomly into two groups. One group was fed with the feedstuff containing 30% of transgenic rice. The remaining (control) group was fed with the feedstuff containing 30% of non-transgenic rice. After 30 days, growth, physiological metabolism parameters such as growth hormone (GH), insulin, glucagon, 3,3′,5-triiodothyronine (T3), thyroxine (T4), thyroid-stimulating hormone (TSH), and the genetic horizontal transformation were analysed. Results indicated that the weight of all rats from the two groups was similar (P>0.05). Also, there was no significant difference in the level of GH, insulin, glucagon, T4, T3 and TSH between the treated and untreated rats. The serum urea nitrogen (SUN), glucose, the glutamate–pyruvate transaminase (GTP), as well as the total cholesterol, of treated rats were almost identical to those of the control (P>0.05). Moreover, no target DNA sequence of rice endogenous sucrose phosphate synthase (SPS) gene or exogenous choline oxidase (codA) gene was detected in organs (liver, muscle, pancreas, etc.) except the stomach, gastrointestinal and rectum contents, and no genetic horizontal transformation was observed in rats fed with transgenic rice.

Primary culture of goat mammary gland cells was achieved by outgrowth of migrating cells from fragments of tissue. The fibroblast and epithelial cells were purified according to their different sensitivity to trypsin and the characteristics of goat mammary epithelial cells were observed under a light microscope. The results showed that the purified goat mammary epithelial cells retained normal characteristics until the 15th passage. The purified mammary epithelial cells propagated and formed a dome-like structure that resembled a nipple and was called a ‘milk orb’. The mammary epithelial cells could produce and secrete milk. There were different cell types: the majority were short shuttle-like or polygons, resembling a beehive; while some were large, flat and round; and others were elongated. The enhanced green fluorescent protein (EGFP) gene was transferred successfully into the goat mammary epithelial cells using electrotransfection, and its expression was observed under a fluoroscope.