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31.
To reveal the effects of herbicide selection on genetic diversity in the outcrossing weed species Schoenoplectus juncoides, six sulfonylurea‐resistant (SU‐R) and eight sulfonylurea‐susceptible (SU‐S) populations were analysed using 40 polymorphic inter‐simple sequence repeat loci. The plants were collected from three widely separated regions: the Tohoku, Kanto and Kyushu districts of Japan. Genetic diversity values (Nei's gene diversity, h) within each SU‐S population ranged from h = 0.125 to h = 0.235. The average genetic diversity within the SU‐S populations was HS = 0.161, and the total genetic diversity was HT = 0.271. Although the HS of the SU‐R populations (0.051) was lower than that of the SU‐S populations, the HT of the SU‐R populations (0.202) was comparable with that of the SU‐S populations. Most of the genetic variation was found within the region for both the SU‐S and SU‐R populations (88% of the genetic variation respectively). Two of the SU‐R populations showed relatively high genetic diversity (h = 0.117 and 0.161), which were comparable with those of the SU‐S populations. In contrast, the genetic diversity within four SU‐R populations was much lower (from h = 0 to 0.018) than in the SU‐S populations. The results suggest that selection by sulfonylurea herbicides has decreased genetic diversity within some SU‐R populations of S. juncoides. The different level of genetic diversity in the SU‐R populations is most likely due to different levels of inbreeding in the populations. 相似文献
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Michihiko Yatazawa Gregori G. Hambali Fuji Uchino 《Soil Science and Plant Nutrition》2013,59(3):285-294
Detached lenticellate warty bark of Inga laurina was first shown to develop acetylene reducing activity (ARA) (18 nmol C2H2red·g-1 (F.W.)·hr-1) after a few days' incubation with ambient air containing 0.10 atm C2H2. Similar N2ase development was found to occur with warty barks of many other plant species including 12 leguminous and 9 non-leguminous trees growing in wet tropical and temperate forests. Among them higher activities (>7 nmol C2H2 red·g-1 (F.W.)·hr-1) were recorded in Inga laurina, Cynometra ramiflora, Cassia siamea, Robinia pseudo-acacia, Albizia julibrissin in the leguminous plants, and Ilex crenata, Ilex pedunculosa, Rhizophora mucronata, Bruguiera gymnorrhiza and Mallotus japonicus in the non-leguminous plants. The development of ARA was often accelerated under lower pO2 (0.05 atm) and pC2H2 (0.05 atm). Complete replacement of O2 with N2 or Ar in the incubation atmosphere resulted in full suppression of the development of N2ase activity. When ARA measurement was made with intact barks of natural stands (Robinia pseudo-acacia, Ilex pedunculosa and Mallotus japonicus), it was found that all of these intact barks were reducing C2H2 linearly without any time lag. The activities recorded were 4.6–11.5 nmol C2H2 red·g-1 (F.W.)·hr-1 corresponding to 1.19–1.27 nmol C2H2 red·cm-2hr-1. These values roughly coincided with ARA of detached warty barks of the same plant species. The present results suggest that in situ N2-fixation in tree barks of the forests would amount to several 10 kg·ha-1·year-1 in temperate and tropical wet forests 相似文献
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H. Uchino T. Watanabe K. Ramu K. L. Sahrawat S. Marimuthu S. P. Wani 《Journal of plant nutrition》2013,36(10):1640-1646
The chlorophyll meter (SPAD-502) is used to estimate nitrogen status of various crops. However, the relationship between SPAD readings and leaf nitrogen concentration (LNC) in sweet sorghum (Sorghum bicolor) has not been fully established. We examined the relationship between SPAD readings and LNC in sweet sorghum in a two-year study; and the effects of leaf thickness on the relationship was also examined. There was a significant relationship between the SPAD reading and LNC at each of two growth stages, but the correlation was weaker when the data for the two growth stages were pooled. This correlation improved when the specific leaf area was introduced as a second independent variable in the multiple regression analysis. This regression equation was applicable to not only different growth stages but also different seasons. The results suggest that the regression equation developed in this study can help in optimizing nitrogen fertilization for sweet sorghum production. 相似文献
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Kazuki Komatsu Tsugumi Iwasaki Kosuke Murata Hideaki Yamashiro Valerie Swee Ting Goh Ryo Nakayama Yohei Fujishima Takumi Ono Yasushi Kino Yoshinaka Simizu Atsushi Takahashi Hisashi Shinoda Kentaro Ariyoshi Kosuke Kasai Masatoshi Suzuki Maria Grazia Palmerini Manuel Belli Guido Macchiarelli Toshitaka Oka Manabu Fukumoto Mitsuaki A. Yoshida Akifumi Nakata Tomisato Miura 《Reproduction in domestic animals》2021,56(3):484-497
Since the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, we have established an archive system of livestock and wild animals from the surrounding ex-evacuation zone. Wildlife within the alert zone have been exposed to low-dose-rate (LDR) radiation for a long continuous time. In this study, we analysed the morphological characteristics of the testes and in vitro fertilization (IVF) capacity of cryopreserved sperm of racoons from the ex-evacuation zone of the FDNPP accident. The radioactivity of caesium-137 (137Cs) was measured by gamma-ray spectrometry, and the measured radioactivity concentration was 300–6,630 Bq/kg in the Fukushima raccoons. Notably, normal spermatogenesis was observed in the seminiferous tubules of the testes, with the germinal epithelium composed of a spermatogenic cell lineage with no evident ultrastructural alterations; freeze-thawing sperm penetration ability was confirmed using the interspecific zona pellucida-free mouse oocytes IVF assays. This study revealed that the chronic and LDR radiation exposure associated with the FDNPP accident had no adverse effect on the reproductive characteristics and functions of male raccoons. 相似文献
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High rates of nitrogen fixation (acetylene reduction) were associated with Equisetum arvense L. and three other species of the same genus. Excised rhizomes and roots were assayed by incubation under ambient air and N2-enriched air (pO2 0.10atm), using the acetylene reduction method. There was a lag of about 1 day before high activity was observed under a pO2 of 0.10 atm, but under ambient air the lag was longer and varied from sample to sample. The duration of this lag usually coincided with that required for the establishment of a definite pO2 level (a threshold value) in the incubation atmosphere. The threshold pO2 value was about 0.15 atm for E. arvense, E. palustre, and E. hyemale, and 0.10 atm for E. ramosissimum. On incubation of the plant materials, acetylene reduction activity (ARA) increased gradually as the atmospheric pO2 decreased, and maximum ARA was observed under a definite pO2 value in the range from 0.04 to 0.01 atm.The highest value was 69nmol C2H44 formed g?1 fresh wt h?1 with a sample of E. arvense atpO2 0.03 atm. When the pO2 decreased below 0.01 atm, ARA decreased very rapidly and finally ceased. Several strains of N2-fixing bacteria were isolated from rhizomes and roots of E. arvense and all were classified as members of the family Enterobacteriaceae. 相似文献
36.
Application study of intracytoplasmic sperm injection for golden hamster and cattle production 总被引：2，自引：0，他引：2
Horiuchi T 《The Journal of reproduction and development》2006,52(1):13-21
This paper describes several technical improvements and our results in hamster intracytoplasmic sperm injection (ICSI), hamster round spermatid injection (ROSI) and bovine ICSI. The hamster is the mammalian species in which ICSI was first tried to produce fertilized oocytes. However, until recently, no live offspring following ICSI have ever been obtained. We reported the birth of live offspring following hamster ICSI. Improved points to success were 1) performing hamster ICSI in a dark room with a small incandescent lamp and manipulating both oocytes and fertilized eggs under microscope with a red light source and 2) injecting sperm heads without acrosomes. Under controlled illumination, the majority of the oocytes injected with acrosomeless sperm heads were fertilized normally, cleaved, and developed into morulae. Nine live offspring (19%) were born by transfer of hamster ICSI-derived embryos. Furthermore, we reported the birth of live offspring following hamster ROSI. About 70% of oocytes injected with round spermatids broken before injection were fertilized normally and about half of them developed to morulae and blastocysts. Three (5%) live young were born by transfer of hamster ROSI-derived embryos. On the other hand, in cattle, the main improvements were 1) injection of spermatozoa immobilized by scoring their tail just before injection into oocytes, and 2) additional ethanol activation 4 h after ICSI. About 70% of oocytes injected were activated 4 h after ICSI, and about 30% of them developed to blastocysts. Twenty-four live calves (39%) were born by non-surgical transfer of ICSI-derived embryos. Those results shows that, at present, live offspring are able to be obtained following hamster ICSI, ROSI and bovine ICSI, but further improvement is required due to higher production efficiency of offspring. 相似文献
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T Hasegawa K Uchida J Yanase K Kitazaki Y Uchino S Nakamura H Sakimoto 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(8):965-966
A 3 year-old female Japanese Black cattle was diagnosed as diabetes mellitus (DM). Hyperglycemia (295 mg/dl), increase of serum fructosamine (487 micromol/l), elevated glycosylated hemoglobin A1 (GHbA1; 10.9%), low concentration of serum insulin (< 1.0 microU/ ml), increased serum glucagon (399 pg/ml), and glucose intolerance (glucose disappearance rate; k=0.53) were noted. On the histopathologic findings in pancreas, insulitis with infiltration of mononuclear cells was found. This case suggests that serum fructosamine and GHbA1 are available parameters for understanding of pathophysiological conditions of bovine DM. 相似文献