Extraction of rice-planting area and identification of chilling damage by remote sensing technology: a case study of the emerging rice production region in high latitude     

Zhongyi Sun  Xiufeng Wang  Haruhiko Yamamoto  Jiquan Zhang  Hiroshi Tani  Guosheng Zhong  Shuai Yin 《Paddy and Water Environment》2017,15(1):181-191

Rice is the second largest staple crop in the world and therefore plays an important role in food security. As a thermophilic crop, rice is sensitive to temperature changes. Thus, research on the chilling damage of rice is essential. The Sanjiang Plain is an emerging rice production area and is located at high latitudes in China, the world’s largest rice-producing country. Landsat data were used to extract rice-planting area from 1985 to 2015. MODIS 13Q1, which was uniformly distributed during the growing period of rice, was used to obtain NDVI values of paddies during 2002–2015. Dynamic Identification Index of sterile-type chilling damage and monitoring standard of delayed-type chilling damage were the proposed methods used in this paper, which were used to judge the chilling damage of rice. The results show that in the study region, the rice-planting area in 2015 is nearly 12 times larger than that in 1985. Delayed-type chilling damage occurred in 2002 and 2009, while sterile-type chilling damage occurred in 2005, 2006, 2009, 2010, 2014, and 2015. Comparing with the prevalent meteorological standards, the results indicate that the index and standards proposed in this paper are precise, applicable, and more sensitive than them. The method is a macroscopic and accurate method to identify chilling damage in rice and can also provide a scientific basis to ensuring the stability of rice yield.  相似文献   

Dual effects of reversed winter–spring temperatures on year‐to‐year variation in the recruitment of chub mackerel (Scomber japonicus)     

Hitoshi Kaneko  Takeshi Okunishi  Takashi Seto  Hiroshi Kuroda  Sachihiko Itoh  Shinya Kouketsu  Daisuke Hasegawa 《Fisheries Oceanography》2019,28(2):212-227

To clarify the effects of temperature on the recruitment of chub mackerel (Scomber japonicus) in the North Pacific, we investigated the influence of winter surface temperature (WST) on spawners at the time of maturity around the spawning grounds and the influence of ambient spring temperature on larvae using estimated temperature (ET) obtained from particle tracking experiments. We found a significant positive correlation between ET approximately 10 days following hatching and the recruitment per spawning stock biomass (RPS) after 2000. The closer (more meandering) the Kuroshio Current (KC) axis was in relation to the spawning ground, the higher (lower) the spring surface temperature and the higher (lower) RPS was in the spawning ground. In contrast, WST inside KC near the maturity/spawning ground was significantly negatively correlated with RPS. A significant negative correlation between the temperatures in winter and spring was detected in the area after 2000, when the conditions of the Pacific decadal oscillation index and the stability of the Kuroshio Extension were synchronous, indicating that KC shifted northward during this time. The reversed temperature pattern was consistent with the winter–spring movement of KC axis in the offshore direction and was correlated with the winter–spring difference in the intensity of the Aleutian low. These results suggest that the annual variation in chub mackerel recruitment after 2000 was strongly affected by the combined effects of ambient temperature because of the reversal of conditions that occurred between winter and spring around the maturity/spawning ground, which was related to the KC path.  相似文献   

Evaluation of stock management procedures for walleye pollock in northern waters of the Sea of Japan using a simulation     

Hiroshi Yamaguchi  Takashi Matsuishi 《Fisheries Science》2008,74(5):955-969

To evaluate walleye pollock stock management procedures in the northern waters of the Sea of Japan, 30-year population dynamics, including uncertainties, were forecast. Errors in current stock size estimation, variability in future recruitment and changes in future fishing mortalities were incorporated. Results of virtual population analysis (VPA) from resampled catch-at-age data with bootstrap methods was used as the current stock size estimation with uncertainty. Performances of each scenario were evaluated using conservation, utilization, stability and reliability factors. Twenty-two management scenarios and continuing the current fishing mortality were evaluated. Scenarios with minor regulation changes and continuing the current fishing mortality showed poor stock conservation performances. Scenarios with minor regulation changes produced good short-term but poor long-term utilization. Stabilities were poor in continuing the current fishing mortality and fishing ban scenarios. Reliability in all scenarios after 30 years was smaller than in continuing the current fishing mortality; however, small differences among scenarios were observed. The simulation results indicated that multilateral assessment is needed to evaluate the management candidates. Uncertainty caused by recruitment variability mostly affected future population dynamics. The role of simulations in the production of effective scientific advice is discussed.  相似文献   

Structure of the intratesticular duct system for sperm emission in the starspotted smooth-hound Mustelus manazo     

Jeong-Chae Park  Jeong-Hoon Lee  Keita Kodama  Hiroshi Urushitani  Yasuhiko Ohta  Toshihiro Horiguchi 《Fisheries Science》2013,79(2):203-211

We conducted histological observation of male germ cells and reproductive organs of the starspotted smooth-hound Mustelus manazo in Tokyo Bay to reveal any abnormality in male reproductive traits, as part of a study to elucidate the factors causing recent fluctuation in abundance of the population. Spermatogenesis proceeded in spermatocysts from the germinal zone in the ventral part of the testis to the degenerative zone in the dorsal part, where the spermatozoa were conveyed into the ciliated lumina of the attached terminal branches of the intratesticular ducts. The intratesticular ducts were classified from their terminal ends into branch, stem, and collecting tubules. The ducts formed in the germinal zone and grew as the spermatocysts developed. An opening formed through the wall of each of the most mature spermatocysts into a branch tubule; bundles of spermatozoa were evacuated through this opening into the branch and then the stem tubule and subsequently into the collecting tubules in the rete testis and the efferent duct connected to the epididymis. Spermatocysts that were unable to emit sperm because of failure of adhesion to the branch tubules were disorganized in situ, as were their spermatozoa. The collapsed spermatocysts seem to be cleared by hemophagocytosis with lymphocytes and leukocytes, which may have been recruited from the epigonal organ. There were no specific abnormalities in the spermatogenesis or the morphological structure of testes, which suggested that an abnormality of male reproductive traits was not the major cause of the recent fluctuation in the population abundance of this species. Details of the intratesticular duct system for sperm emission to the epididymis are the first findings in elasmobranchs worldwide.  相似文献   

Silicon content in rice seedlings to protect rice blast fungus at the nursery stage   总被引：1，自引：0，他引：1  

Tsuyoshi Hayasaka  Hiroshi Fujii  Tsuneo Namai 《Journal of General Plant Pathology》2005,71(3):169-173

To control rice blast effectively at the nursery stage, the absolute SiO₂ content necessary for rice plants to resist blast disease was investigated using various rice cultivars and soils. Nine rice cultivars with different complete resistance genes and different degrees of partial resistance were grown on nursery soils amended with silica gel at different rates to change the SiO₂ content of rice plant. The rice seedlings were then inoculated 28 days after sowing with Pyricularia grisea to estimate their blast resistance. In all rice cultivars, the number of lesions was significantly reduced when SiO₂ content increased in the rice seedling; lesions were reduced to 5%–20% of the number on the seedlings grown in soil without silica gel when the seedling SiO₂ content reached 5%. Additionally, the susceptibility to blast disease of rice seedlings grown on eight soils collected from different districts, with varying amounts of silica gel, was compared. The number of lesions decreased significantly when the SiO₂ content in the seedlings reached 5%. These results suggest that SiO₂ content of at least 5% in the rice plant can control this disease at the nursery stage under any conditions.  相似文献   

Spatiotemporal pattern of EphA4 gene expression in developing quail limb buds     

Kenjiro ARISAWA  Shigenobu YAZAWA  June-ichi EGUCHI  Hiroshi KAGAMI  Tamao ONO 《Animal Science Journal》2005,76(1):65-71

  相似文献   

Identification of cDNA for the HSPA2, HSPA5 and HSPA8 orthologs of the heat shock protein 70 family from guinea fowl (Numida meleagris)     

Shigehisa IWAMOTO  Yohei KOIKE  Kazuyoshi HOSOMICHI  Hiromi HARA  Yutaka YOSHIDA  Hiroshi OGAWA  Kei HANZAWA 《Animal Science Journal》2005,76(5):519-524

  相似文献   

Antifungals produced by dinoflagellates—gambieric acids     

Hiroshi Nagai  Yuzuru Mikami  Takeshi Yasumoto 《Pest management science》1995,44(1):92-94

  相似文献   

Trophinin is expressed in the porcine endometrium during the estrous cycle     

Nakano S  Kishi H  Ogawa H  Yasue H  Okano A  Okuda K 《The Journal of reproduction and development》2003,49(2):127-134

We investigated endometrial expression of trophinin mRNA and protein, homophilic cell adhesion molecules, during the estrous cycle of gilts. An immunopositive reaction for trophinin was observed in the luminal and glandular epithelia of the endometrium at all stages of the estrous cycle, but not in endometrial stromal cells or the myometrium. A partial coding sequence of porcine trophinin was similar to sequences in humans and mice, with homologies of 75% and 70%, respectively. As in humans and mice, the trophinin gene is expressed in the endometrium. Trophinin, however, is expressed in the endometrium of the pig throughout the estrous cycle, higher expression levels were observed at some points of the luteal phase, as in humans. These findings suggest that regulation of trophinin gene expression in the pig is different from that in mice, but similar to that in humans. Furthermore, the present results suggest that the pig might be a suitable model for studying the physiological importance of trophinin in early pregnancy in humans.  相似文献   

Percutaneous ultrasound-guided over-the-wire catheterization of the portal and hepatic vessels in cattle     

Mohamed T  Oikawa S  Nakada K  Kurosawa T  Sawamukai Y  Sato H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(7):821-824

A new method for catheterization of the portal and hepatic veins in cattle by means of the over-the-wire system was investigated to maintain more reliable long-term patency of catheters. Four cattle were used to evaluate the success rate, patency and safety of the procedure. The catheters, coated by urokinase were patent as long as they were in situ. In addition, the introducer was useful to prevent the catheter from being broken. No complications developed during the10 days after the procedure. Two cows were then euthanized. Post mortem findings were minimal. The results of the study reported here are promising, the benefits are significant and there is no apparent disadvantage to its use.  相似文献