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71.
Yoshio Yoshida 《Euphytica》1962,11(1):95-111
Radiation breeding for the introduction of additional desirable characters into improved varieties in autogamous plants, especially in cereals, would be much more feasible if more efficient screening methods could be found. Such methods are proposed in this report. From the standpoint of the theory of probability, it is intended to establish effective screening methods by which a desirable X2 mutant can be detected in a minimum total of X2-plants, and/or X1- and X2-plants in the aggregate.The relative efficiencies of four new methods and the standard method are compared, the improved ear-to-row method (method B), the one-plant-one-grain method (method C), the one-plant-two-grain method (method D) and one-plant-three-grain method (method E) all of which are more effective than the conventional ear-to-row method (method A). In method B, the total number of X2-plants required to recover at least one desirable X2-plant is obtained when the probability of detecting at least one X2-line with one or more desirable mutants among X2-lines is equal to the probability of detecting at least one desirable mutant among plants in that X2-line. In methods C, D and E, one, two or three grains respectively, taken from each of the X1-plants of the number required to detect at least one desirable X2-plant, are sown to obtain corresponding X2-plants.The number of X1-plants, total X2-plants, and X1- and X2-plants in the aggregate required to obtain at least one desirable mutant (m, mn and m+mn respectively) shows the following relations: method C>D>A>E>B for m, ABED>D>C for mn and ABC>D>E (the last two being very close to each other) for m+mn.Each of the new methods B, C, D and E will be applicable in radiation breeding. When the discrimination of a mutant is difficult method B will be useful. On the contrary, when a mutant is easily distinguishable, method C, with dense planting in X1, will frequently be much better. In some cases methods D and E, especially D, will be more useful in the practice of radiation breeding than method C. Method A should not be used in any case. 相似文献
72.
利用介电特性对食品加工过程进行非破坏性检测技术的研究 总被引:1,自引:0,他引:1
选用标准蔗糖和新鲜胡萝卜、葱为材料,研究干燥过程中原料电物性及水分含量变化规律的相关性。结果表明,60℃温度下热风干燥几种新鲜蔬菜,其水分含量随着干燥时间的增加而下降,电容值的变化趋势与水分的变化相同,两者存在极显著的线性相关性。水分的变化规律可以用相对应点的电容的变化来说明,从而对干燥终点的非破坏性及连续性检测和控制成为可能。 相似文献
73.
The Wx
b gene, one of the alleles at the rice waxy(wx) locus, is activated at cool temperatures during seed development, andas a result, a large amount of amylose is accumulated causing a reductionin rice grain quality. We found that the seeds of a du mutant couldbe visibly distinguished depending on whether they matured at cool ornormal temperatures. Using these characteristics, we isolated a mutantcandidate insensitive to cool temperatures. While the amylose content inthe original line was about 2% at a normal temperature (28 °C)and 12% at a cool temperature (21 °C), in the mutant candidate(coi) the amylose content was not affected by temperatures, i.e. theamylose content was about 3% at both temperatures. This finding incombination with the results of an immunoblot analysis indicated that theabsence of an increase in the amylose content in this mutant was caused bya constant level of Wx gene expression at normal and cooltemperature. Genetic analysis revealed that this insensitivity to cooltemperatures was caused by a single recessive mutation. This mutantshould be useful in breeding programs designed to produce rice of desiredquality at cool temperatures and in understanding genetic and molecularmechanisms that respond to slight changes in temperature. 相似文献
74.
Tomohide Uno Satoru Kaji Tatsushi Goto Hiromasa Imaishi Masahiko Nakamura Kengo Kanamaru Hiroshi Yamagata Yoshio Kaminishi Takao Itakura 《Pesticide biochemistry and physiology》2011,101(2):93-102
Through the use of a number of bioconversion experiments we demonstrated that P450 proteins (CYP1A9 and CYP1C1) from Japanese eel (Anguilla japonica) metabolized a number of herbicides and the drug phenacetin. We performed bioconversion experiments in which substrates were added directly to incubation medium. The resulting metabolites were extracted and analyzed by high-performance liquid chromatography. Proteins CYP1A9 and CYP1C1 metabolized 50 nmol of the drug phenacetin to yield 12.1 and 1.1 nmol of product (acetaminophen), respectively. Further incubation of CYP1A9 with 50 nmol of the herbicides chlorotoluron, diuron, linuron, simazine, or atrazine yielded 16.5, 18.5, 7.3, 1.6, or 0.8 nmol of product, respectively. CYP1C1 also metabolized linuron, diuron, and simazine yield 5.4, 4.6, or 0.7 nmol of product, respectively. Next, polyclonal antibody was isolated by immunizing with two conjugated-peptides (amino acid residues 272–290 and 294–310) of CYP1A9. This antibody did not recognize human CYP1A2 or CYP1C1. Western blotting using the antibody revealed one band in the livers of Japanese eel and tilapia (Oreochromis niloticus). Theses results suggest that CYP1A9 and CYP1C1 metabolize herbicides, and that CYP1A9 is an useful biomarker of contamination when detected with this antibody. 相似文献
75.
Munehiro Warashina Masanobu Tanaka Yoshio Tsujino Tuguo Mizoguchi Siro Hatakeyama Yasuaki Maeda 《Water, air, and soil pollution》2001,130(1-4):1505-1510
The results of ambient sulfur dioxide (SO2) and nitrogen dioxide (NO2) concentrations measured in ten cities of China and Korea by the improved passive samplers are reported. The property of this sampler is the utilization for the long-term exposure to the high level of SO2 and NO2. In this method, the conversion coefficients from the analytical data to the ambient concentrations were obtained from the comparison with the direct concentrations through the automatic analyzers for SO2 and for NO2, respectively. The interesting monthly variations were observed in the ambient SO2 and NO2 concentrations measured by this passive sampler method, which seems to give important information to the formation of acid rain in these countries. 相似文献
76.
Michinari YOKOHAMA Kenta WADA Masaru FUJITA Mai KOTANI Yoshio NAGURA Masako KANNO Kou NOMURA Takashi AMANO Yoshiaki KIKKAWA 《Animal Science Journal》2011,82(6):773-781
The coat of a goat, like that of many mammalian species, consists of an outer coat of coarse hairs and an under coat of fine, downy hairs. The coarse guard hairs are produced by primary follicles and the finer cashmere hairs by secondary follicles. We previously reported that hair keratins are components of cashmere hair, and proteomic analysis revealed that their expression is elevated in winter coat hair. To determine detailed characterization, we have cloned keratin 33A gene, a major highly expressed keratin in winter, and then analyzed the expression of goat hair coat. By Western analysis, we detected that keratin 33A protein is expressed only in hair coat among the various goat tissues. Moreover, the expression level in winter has increased in cashmere high‐producing Korean native breed, whereas the expression levels between summer and winter had not changed in cashmere low‐producing Saanen. In addition, by immunohistochemistry we determined that keratin 33A is localized in the major cortex portion of cashmere fiber. These results confirm that keratin 33A is a structural protein of goat cashmere hair fiber. 相似文献
77.
Kazuaki TANAKA Tatsuya TAKIZAWA Hayato MURAKOSHI Tashi DORJI Maung Maung NYUNT Yoshizane MAEDA Yoshio YAMAMOTO Takao NAMIKAWA 《Animal Science Journal》2011,82(1):52-56
The mithun (Bos frontalis), synonymous with mithan and gayal, is considered to be a domesticated form of gaur (B. gaurus). However, there has been a controversy concerning its origin. In an effort to address this issue, the mitochondrial cytochrome b (cytb) genes of 20 mithun from Myanmar and 13 from Bhutan were sequenced to trace its maternal origin. Seven cytb haplotypes were found in the 33 mithun, and the phylogenetic tree for these haplotypes clearly showed three embranchments involving five gaur types, a B. indicus type, and a B. taurus type. Sixteen Myanmar and 12 Bhutan mithun had gaur haplotypes, while a B. indicus haplotype was found in three Myanmar and one Bhutan mithun. The B. taurus haplotype was detected in a single Myanmar animal. These results demonstrated that the principal maternal origin of mithun was gaur and suggested that it was directly domesticated from gaur. However, some introgression of domestic cattle existed in current mithun populations. The presence of cattle mtDNA raised the question of how many cattle nuclear genes might have been integrated into the gene pool of mithun. 相似文献
78.
Masahide NISHIBORI Makoto HANAZONO Yoshio YAMAMOTO Masaoki TSUDZUKI Hiroshi YASUE 《Animal Science Journal》2003,74(5):437-439
Among the chicken breeds, White Leghorn (WL) and White Plymouth Rock (WR) are major breeds and have different history in their establishments. Whole mitochondrial DNA of the breeds were sequenced in order to elucidate the genetic relationship between the breeds. The lengths of the two WL and two WR mitochondrial DNA were found to be 16 788 and 16 785 base pairs, respectively. When the DNA sequences were compared, the similarity was found to be 99.96% (six nucleotide differences). In addition, the present study conformed the existence of an extra nucleotide ‘C’ in NADH dehydrogenase subunit 3 (ND3) of the chicken mitochondrial DNA, which has been consistently observed in Galliformes. 相似文献
79.
Yoshio Izawa Matazaemon Uchida Tatsuyoshi Sugimoto Toshiro Asai 《Pesticide biochemistry and physiology》1985,24(3):343-347
Buprofezin (Applaud, 2-tert-butylimino-3-isopropyl-5-phenyl-3,4,5,6-tetrahydro-2H-1,3,5-thiadiazin-4-one) strongly inhibited the [3H]chitin synthesis from N-acetyl-d-[1-3H]glucosamine in the brown rice planthopper, Nilaparvata lugens Stål. No inhibition was observed for [3H]-labeled protein biosynthesis from [5-3H]glucose or l-[3,5-3H]tyrosine but [3H]-labeled nucleic acid synthesis from [5-3H]glucose was weakly reduced by buprofezin. The lethal activity of buprofezin analogs related well to their inhibitory potency against chitin biosynthesis in N. lugens nymphs. 相似文献
80.
Masachika Hirano Nobushige Itaya Isao Ohno Yoshio Fujita Hirosuke Yoshioka 《Pest management science》1979,10(4):291-294
Thirteen pyrethroid-type esters of substituted 1(or 3)-hydroxymethylimidazolidine-2, 4-dione were synthesised and their knockdown activities against houseflies, mosquitoes and cockroaches were examined. Knockdown activities of 2,4-dioxo-1-prop-2-ynylimidazolidin-3-ylmethyl esters in oil solutions were higher than those of known knockdown pyrethroids; three of the compounds also possessed strong knockdown and flushing-out activities against cockroaches. 相似文献