溶血磷脂酸( Lysophosphatidic acid, LPA)是一种小分子甘油磷脂，在多种动物细胞中具有生长因子和激素样活性。LPA通过结合G蛋白偶联受体,激活下游信号通路，产生促卵母细胞成熟，提高胚胎发育率，促进细胞增殖等生物学效应。绵羊是我国重要的家畜之一，其体外受精效率较其他物种偏低,且目前仍未建立真正的绵羊胚胎干细胞。本研究通过在绵羊体外受精过程及囊胚接种细胞培养过程中添加LPA，以探究LPA对绵羊体外受精以及囊胚接种细胞培养的影响。首先，我们对绵羊的体外受精体系进行了筛选，选取了两种成熟液与两种SOF液进行组合，通过比较不同体系间的成熟率、卵裂率和囊胚率，最终找到最优的体外受精的体系，即IVM Ⅱ and SOF Ⅱ。然后，在绵羊体外受精过程中添加不同浓度的LPA，探讨LPA浓度对绵羊体外受精的影响。结果显示，当LPA浓度为0.1 μmol L^-1 - 10 μmol L^-1之间时，随着LPA浓度的增加，绵羊卵母细胞体外成熟率、囊胚率逐渐上升(P < 0.05)，卵裂率无显著变化(P > 0.05),囊胚形态正常；当LPA浓度达到15 μmol L^-1时，成熟率、卵裂率、囊胚率均出现显著下降 (P < 0.05)，且囊胚形态发生异常，胚胎内细胞团聚集不正常，囊胚内部出现分区，不能发育成为优质的囊胚。另外，随着LPA浓度在0.1 μmol L^-1- 10 μmol L^-1范围内逐渐增大，LPAR2、LPAR4、TE相关基因CDX-2和多能性相关基因OCT-4在绵羊早期体外受精胚胎中的mRNA表达量也逐步增加。而15 μmol L^-1 LPA处理组中，早期胚胎LPAR2、LPAR4、CDX-2和OCT-4的表达量均显著低于LPA - 10 μmol L^-1处理组(P<0.05)。最后，我们将绵羊体外受精囊胚接种在不同培养体系,尝试建立胚胎干细胞。 结果表明，LPA使接种后的囊胚细胞向TSC样细胞生长。随着LPA浓度从0 μmol L^-1增加到10 μmol L^-1, OCT-4和CDX-2的蛋白免疫荧光强度和mRNA丰度增强(P < 0.05)，而15 μmol L^-1 LPA则显著降低OCT-4和CDX-2在囊胚接种细胞中的表达(P < 0.05)。同时，10 μmol L^-1的LPA处理后，LPAR2和LPAR4蛋白表达显著增加。综合上述实验结果，LPA可促进绵羊体外受精早期胚胎发育,并促进囊胚接种细胞向TSC方向生长，为大动物体外受精及胚胎干细胞建系提供参考。

Cereal aphids are major insect pests of wheat, which cause significant damages to wheat production.  Previous studies mainly focused on the resistance of different wheat varieties to one specific aphid species.  However, reports on the physiology and defense responses of wheat to different cereal aphids are basically lacking.  In this work, we studied the feeding behavior of three cereal aphids: the grain aphid, Sitobion avenae (Fabricius), the greenbugs, Schizaphis graminum (Rondani), and the bird cherry-oat aphid, Rhopalosiphum padi (Linnaeus) on winter wheat, and the physiology and defense responses of wheat to the infestation of these cereal aphids with focus on how these cereal aphids utilize divergent strategies to optimize their nutrition requirement from wheat leaves.  Our results indicated that S. graminum and R. padi were better adapted to penetrating phloem tissue and to collect more nutrition than S. avenae.  The harm on wheat physiology committed by S. graminum and R. padi was severer than that by S. avenae, through reducing chlorophyll concentration and interfering metabolism genes.  Furthermore, cereal aphids manipulated the plant nutrition metabolism by increasing the relative concentration of major amino acids and percentage of essential amino acids.  In addition, different cereal aphids triggered specific defense response in wheat.  All of these results suggested that different cereal aphids utilize divergent strategies to change the physiological and defense responses of their host plants in order to optimize their nutrition absorption and requirement.  These findings not only extend our current knowledge on the insect–plant interactions but also provide useful clues to develop novel biotechnological strategies for enhancing the resistance and tolerance of crop plants against phloem-feeding insects.

A dry flowable formulation of Clonostachys rosea with fungicidal activity against Sclerotinia sclerotiorum was prepared by spray drying.  The formulation was optimized by a four-factor, three-level orthogonal experiment to screen inert ingredients and spray-drying conditions.  The optimal dry flowable formulation of C. rosea included 30% C. rosea (ratio of conidia powder and its fermentation broth is 1:3), 3% Morwet EFW, 4% k12, 10% Morwet D425, 9% sodium salt of polynaphthalene sulphonic acid (NNO), 5% croscarmellose sodium, 5% (NH₄)₂SO₄, 0.5% carboxymethyl cellulose sodium (CMC-Na), 1% oxalic acid and palygorskite (carrier) up to 100%.  The formulation exhibited good physical characteristics, such as high dispersibility, viability and a long shelf life.  Plate antagonism tests and pot trials indicated that the dry flowable formulation was very effective against S. sclerotiorum, with control efficiency of up to 88.30%.  This dry flowable formulation of C. rosea is a new potential commercial fungicide for spray drying to control S. sclerotiorum.  

Gossypium hirsutum races are believed to be potential reservoirs of desirable traits, which can play crucial roles to overcome the existing narrow genetic base of modern Upland cotton cultivars.  However, prior to utilizing the races in cotton improvement programs, understanding their genetic constitutions is needed.  Thus, this study used molecular and morphological techniques to characterize 110 G. hirsutum germplasm including 109 semi-wild accessions and one Upland cotton cultivar, CRI12.  In the study, 104 SSR markers detected 795 alleles, with an average of 7.64 alleles per marker, ranging from 3 to 14, and average polymorphism information content (PIC) value of 0.71.  And 96 of the markers were found to be highly informative, with PIC value≥0.50.  Pairwise genetic similarity coefficient across the accessions ranged from 0.19 to 1.00, with an average value of 0.46.  Morphological characterization was done using fiber length, fiber strength, micronaire, fiber uniformity index, and fiber elongation.  Pairwise taxonomic distance within the accessions ranged from 0.17 to 3.41, with a mean of 1.33.  The SSR and fiber quality traits data set based unweighted pair group method of arithmetic mean (UPGMA) analysis grouped the accessions into 7 and 12 distinct clusters, respectively, that corresponds well with the results of principal component analysis (PCA).  Our study revealed the existence of vast molecular and morphological diversities within the accessions and provided valuable information on each semi-wild accession for quick and better informed germplasm utilization in cotton breeding programs.   

The brown planthopper, Nilaparvata lugens is an economically important pest on rice plants. This species produces macropterous and brachypterous morphs in response to environmental cues, which makes it very difficult to control. The molecular basis of wing patterning in N. lugens is still unknown. It is necessary to identify wing patterning genes of N. lugens, and also to clarify the expression differences of wing patterning genes between macropterous and brachypterous morphs. High-throughput deep sequencing of transcriptome of N. lugens wing pad yielded 116 744 580 raw reads and 113 042 700 clean reads. All the reads were assembled into 55 963 unigenes with an average length of 804 bp. With the E-value cut-off of 1.0E–5,18 359 and 2 883 unigens had hits in NCBI-NR (NCBI non-redundant protein sequences) and NCBI-NT (NCBI nucleotide sequences) databases, respectively. A total of 16 502 unigenes were assigned to GO (gene ontology) classification, 9 709 ungenes were grouped into 26 COG (cluster of orthologous groups of proteins) classifications, and 6 724 unigenes were assigned to different KEGG (Kyoto encyclopedia of genes and genomes) pathways. In total, 56 unigenes which are homologous to wing patterning genes of Drosophila melanogaster or Tribolium castaneum were identified. Out of the 56 unigenes, 24 unigenes were selected, and their expression levels across the five nymphal stages between macropterous strain and brachypterous strain were examined by qRT-PCR. Two-way ANOVA analysis showed that development stage had significant effects on the expression level of all the 24 genes (P<0.05). The expression levels of 8 genes (Nlen, Nlhh, Nlsal, NlAbd-A, Nlwg, Nlvg, Nlexd and NlUbx) were significantly affected by wing morph. This is the first transcriptome analysis of wing pads of hemimetabolous insect, N. lugens. The identified wing patterning genes would be useful resource for future exploration of molecular basis of wing development. The 8 differentially expressed wing patterning genes between macropterous strain and brachypterous strain would contribute to explain molecular mechanism of wing-morph differentiation in N. lugens.

This study explored spatial explicit multiple cropping efficiency (MCE) of China in 2005 by coupling time series remote sensing data with an econometric model - stochastic frontier analysis (SFA). We firstly extracted multiple cropping index (MCI) on the basis of the close relationship between crop phenologies and moderate-resolution imaging spectroradiometer (MODIS) enhanced vegetation index (EVI) value. Then, SFA model was employed to calculate MCE, by considering several indicators of meteorological conditions as inputs of multiple cropping systems and the extracted MCI was the output. The result showed that 46% of the cultivated land in China in 2005 was multiple cropped, including 39% doublecropped land and 7% triple-cropped land. Most of the multiple cropped land was distributed in the south of Great Wall. The total efficiency of multiple cropping in China was 87.61% in 2005. Southwestern China, Ganxin Region, the middle and lower reaches of Yangtze River and Huanghuaihai Plain were the four agricultural zones with the largest rooms for increasing MCI and improving MCE. Fragmental terrain, soil salinization, deficiency of water resources, and loss of labor force were the obstacles for MCE promotion in different zones. The method proposed in this paper is theoretically reliable for MCE extraction, whereas further studies are need to be done to investigate the most proper indicators of meteorological conditions as the inputs of multiple cropping systems.

Telomeres form the ends of eukaryotic chromosomes and serve as protective caps that keep chromosomes structure independency and completeness. The first plant telomere DNA was isolated from Arabidopsis thaliana and was shown to have tandemly repeated sequence 5´-TTTAGGG-3´. The Arabidopsis-type telomere has been found in many plants, but several reports indicate that this sequence is absent in some plants. Up to now, no research has been conducted on the telomere of cotton. In this paper, the Arabidopsis-type telomere sequence was amplified and cloned using the primers designed based on the fragment containing telomere sequence in an Arabidopsis bacterial artificial chromosome (BAC). Fluorescence in situ hybridization (FISH) with cotton metaphase chromosomes using the Arabidopsis-type telomere sequence as probes indicated that the signals were located at all chromosome ends of seven diploid and two tetraploid cotton species with different signal intensities among chromosome complements of different cotton species, even between long and short arms of the same chromosome. To identify the signals of FISH, the genome DNA of Xinhai 7, a cultivar of Gossypium barbadense, digested by BAL-31 nuclease was introduced in this study. The result of BAL-31 digestion indicated that the hybridization signals of FISH represent the outermost DNA sequence of each cotton chromosomes. So we first proved that the telomeric repeats of cotton cross-hybridize with that of Arabidopsis. The results of terminal restriction fragment (TRF) showed significant variation in telomere length among cotton species. The telomere length of cultivated cotton was close to 20 kb and was larger than those of wild cotton species whose telomere length ranged from 6 to 20 kb.

Transgenic Bt rice has been shown to be an effective means of controlling Lepidoptera pests of rice. However, the potential roles of transgenic rice on planthoppers and their predators need to be investigated before its commercialization. Population density, species dominance and population dynamics are important parameters of arthropods populations in field. So the impacts of three transgenic Bt rice strains expressing cry1Ab/cry1Ac, cry1C and cry2A on population density, species dominance and population dynamics of three species of planthoppers (Nilaparvata lugens, Sogatella furcifera and Laodelphax striatellus) and their three main predators (Cyrtorhinus lividipennis, Pirata subpiraticus and Theridium octomaculatum) were evaluated at three sites in Hubei Province, China, in the current study. The results showed that among three species of planthoppers, both in transgenic and non-transgenic rice field, the predominant species of planthoppers within phytophagous guild was S. furcifera at any site either growing season (46-50%). Significantly higher population density of N. lugens was observed in T2A-1 field relative to Minghui 63 field at Wuxue in 2010. The species dominance of predator, P. subpiraticus, in TT51 field was significantly higher than that in T1C-19 and T2A-1 fields in 2009 at Xiaogan site. Sampling date significantly influenced six arthropods except for P. subpiraticus in 2010. The interaction between rice strain×sampling date had no significant adverse effects on the population dynamics of three species of planthoppers and their predators, except for several individual species in 2009. The interaction among rice strain×sampling date×sampling site also had no significant effect on six arthropods except for S. furcifera in 2009. The results indicated that transgenic Bt rice expressing cry1Ab/cry1Ac, cry2A and cry1C had no significant adverse effects on the population dynamics of three planthoppers and their predators in most investigated data and sampling site.