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101.
[目的]籽粒硬度是重要的小麦品质性状,了解新生疆小麦地方品种籽粒硬度的变异类型和分布,为新疆小麦品质育种提供遗传信息.[方法]利用单籽粒硬度仪(SKCS)和PCR扩增、酶切及DNA测序技术,结合改良的Friabilin提取及电泳分析方法,对105份新疆小麦地方品种的籽粒硬度及Pina和Pint等位基因进行研究.[结果]新疆小麦地方品种以硬质类型为主,平均硬度值为63.5.新疆小麦地方品种Puroindoline基因共有9种突变型,分别是Pina-D1a/Pinb-D1a,Pina-D1a/Pinb-Dlb,Pina-D1a/Pint-D1p,Pina-D1k ()/,Pina-D1l/Pinb-D1a,Pina-D1r/Pinb-D1a,Pina-D1a/Pinb-D1ab,Pina-D1a/Pint-Dlac和Pina-D1b/Pinb-D1p,其中Pina-D1 r/Pinb-D1a为新发现的突变型.新疆小麦地方品种Puroindoline基因型以Pina-D1a/Pinb-D1p为主导类型,共有62份,占59.1;;其Pina-D1k()/和Pina-D1 a/Pint-D1ab两种突变型与其地理来源和生态型密切相关,主要分布在南疆冬小麦中.Pina-D1a/Pinb-D1a(野生型)的硬度值显著低于突变型,Pina-Dlk()/的硬度值最高,但Pins-D1k ()/ ,Pina-D1a/Pinb-D1p和Pina-D1a/Pinb-D1ab的硬度值差异不显著.[结论]新疆小麦地方品种籽粒硬度及其Puroindoline等位变异和分布信息能为新疆小麦品质改良和引种提供理论依据.  相似文献   
102.
Tolpyralate, a new selective postemergence herbicide developed for the weed control in corn, possesses a unique chemical structure with a 1-alkoxyethyl methyl carbonate group on the N-ethyl pyrazole moiety. This compound shows high herbicidal activity against many weed species, including glyphosate-resistant Amaranthus tuberculatus. Tolpyralate targets 4-hydroxyphenylpyruvate dioxygenase (4-HPPD), which is involved in the tyrosine degradation pathway. Inhibition of the enzyme destroys the chlorophyll, thereby killing the susceptible weeds. Details of tolpyralate discovery, structure optimization, and biological activities are described.  相似文献   
103.
104.
An intrauterine insemination technique using a fiberscope was investigated in the giant panda. A septal wall was present about 5 cm from the vulva, the external urethral orifice was present in the ventral region, and the entrance (pseudocervix) to the vagina was present in the dorsal region. The uterovaginal region protruded in the dorsal region about 15 cm from the pseudocervix. The external uterine orifice was present in the uterovaginal region, revealing that intrauterine insemination can be easily performed. This technique may greatly contribute to artificial reproduction of the giant panda.  相似文献   
105.
Ultrasonography-guided transabdominal needle aspiration was carried out to remove 3 to 14 ml of purulent matter from the cavities of prostatic abscesses in 6 dogs, and the same volume of tea tree oil was injected into the cavities to treat the abscesses. The same treatment was repeated 3 weeks later in 4 dogs, and subsequent disappearance of the purulent matter in the cavities and a marked reduction in the volume of the cavities were observed. These findings indicate that the treatment of prostatic abscesses by aspiration of the purulent matter and injection of tea tree oil into the cavities is very effective in dogs.  相似文献   
106.
An insertion/deletion variant of a thymine base (T5 and T6) in exon 2 of porcine beta 3‐adrenergic receptor (ADRB3) gene has been described. In the current study, we made an association study between the ADRB3 polymorphisms and production traits in 735 Duroc pigs. The allele frequencies for the T5 and T6 alleles in our study population were 0.433 and 0.567, respectively. Any associations between ADRB3 genotype and average daily weight gain during test period, or backfat thickness and intramuscular fat content were not detected in either sex. However the size of the loin eye muscle area (EMA) was significantly associated with ADRB3 genotypes in gilts. T6‐homozygous gilts had a higher mean of EMA (40.6 ± 0.6 cm2) than T5‐homozygous (38.1 ± 0.4 cm2, P = 0.002) and heterozygous (38.8 ± 0.3 cm2, P = 0.034) gilts. This association was not detected in males. In addition, a multiple traits animal model best linear unbiased predictor (BLUP) analysis revealed that the T6‐homozygous genotype had positive effects on breeding value of EMA. Accordingly, we suggest that ADRB3 polymorphism has the potential to be an important genetic marker for prediction of EMA in Duroc pigs.  相似文献   
107.
BACKGROUND: Target‐site resistance is the major cause of herbicide resistance to acetolactate synthase (ALS)‐ and acetyl‐CoA carboxylase (ACCase)‐inhibiting herbicides in arable weeds, whereas non‐target‐site resistance is rarely reported. In the Echinochloa phyllopogon biotypes resistant to these herbicides, target‐site resistance has not been reported, and non‐target‐site resistance is assumed to be the basis for resistance. To explore why target‐site resistance had not occurred, the target‐site genes for these herbicides were isolated from E. phyllopogon, and their expression levels in a resistant biotype were determined. RESULTS: Two complete ALS genes and the carboxyltransferase domain of four ACCase genes were isolated. The expression levels of ALS and ACCase genes were higher in organs containing metabolically active meristems, except for ACC4, which was not expressed in any organ. The differential expression among examined organs was more prominent for ALS2 and ACC2 and less evident for ALS1, ACC1 and ACC3. CONCLUSION: E. phyllopogon has multiple copies of the ALS and ACCase genes, and different expression patterns were observed among the copies. The existence of three active ACCase genes and the difference in their relative expression levels could influence the occurrence of target‐site resistance to ACCase inhibitors in E. phyllopogon. Copyright © 2012 Society of Chemical Industry  相似文献   
108.
The loss of biodiversity is an ongoing problem and it is essential that a framework is established for revealing the status, identifying threats and monitoring future changes of populations. This study focuses on wader populations in the East Asian-Australasian flyway, and aims to develop a three-step framework for monitoring the status of populations. First, population changes of waders are quantified by estimating population indices from nationwide survey data in Japan between 1975 and 2008. Second, species characteristics shared by declining waders are identified using a phylogenetic comparative method. Finally, based on the revealed characteristics of declining species, composite indices are created for monitoring changes in wader communities in the East Asian-Australasian flyway. The estimated population indices revealed that 12 species out of 41, and 16 out of 42 have declined significantly during spring and autumn migration, respectively, in at least one of the past 10, 20 or 30 year-periods. Phylogenetic comparative analysis revealed that both the use of rice fields and dependence on the Yellow Sea negatively affected the population trends of waders. These results are consistent with the hypothesized negative impact of agricultural intensification caused by land consolidation in Japanese rice fields, and habitat loss and/or degradation in the Yellow Sea caused by the rapid growth of populations and economies in China and South Korea. The framework developed in this study can be applied to a wide range of species, and should play an important role in monitoring population trends and identifying threats to those species in future.  相似文献   
109.
ABSTRACT: Poly(α- L -guluronate)lyase, as one of alginate lyases, was purified from the culture medium of a marine bacterium, Pseudomonas sp. strain F6, to an electrophoretically homogeneous state. The enzyme was shown to have a molecular mass of 36 kDa by sodium dodecylsulfate–polyacrylamide gel electrophoresis (SDS-PAGE), and was most active at around pH 7.5 and was stable between pH 6.5 and pH 8.5. In the thermal stability experiments, the enzyme's activity diminished through an intermediate state with increasing incubation temperatures and was finally lost when heated at 100°C for 15 min. The addition of hen egg-white lysozyme to the enzyme decreased thermal stability dramatically. The apparent retention of enzyme activity (approximately 50%) was observed after the addition of 6 M guanidine hydrochloride and 8 M urea. Enzyme activity was lost completely with 10 mMSDS, while the ordered structure, which is considered likely to be β-structure, was markedly created. The similar conformational feature has also been created in marine bacterial and mollusc enzymes and the β-structure is commonly observed in polyuronate lyases. The divalent cation (Ca2+) promoted the activity of the calcium chelator-treated enzyme significantly, suggesting that Ca2+ is involved in the formation of the active intermediate between the acidic uronate(s) and amino acid side-chain(s) of the enzyme.  相似文献   
110.
Wet deposition monitoring was conducted at six rural stations in western Japan, during the period from 1987 through 1996. Long-term trends in the concentration of non-sea salt ions were analyzed on the basis of the data obtained. The monitoring results indicated that annual average concentrations of NO3 ? and NH4 + in precipitation significantly increased on the order of 45%, and that of nss-Ca2+ and nss-SO4 2?, concentrations did not change over the past 10 years. The ratio of NO3 ?/nss-SO4 2? in precipitation significantly increased, the ratio of NO3 ?/NH4 + showed no marked fluctuations, and the ratio of [nss-Ca2++NH4 +]/[nss-SO4 2?+NO3 ?] slightly increased during the period. These findings suggested that the wet deposition of NO3 ? and NH4 + in western Japan, particularly that in the winter season, was influenced by the long-range transport of nitrogen oxides and ammonia from the Asian continent.  相似文献   
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