利用内部信息的农用自动引导行走车的研究(第1报)——日本的研究现状及本研究的方法概述

从介绍农业机器人入手,对自动引导行走系统的研究及在农业领域的应用进行论述,重点说明了农业领域在该研究方面所具有的特殊性。概述了此项研究使用的方法。     

水稻短根的遗传分析

 用水稻短根突变化RM1、RM2与原品种Ohchikara杂交配成两个组合的P₁、 P₂、 F₁、 F₂、 B₁₁、B'₁₁、B₁₂、 B'₁₂ 以及F₃世代，调查冠根长度，研究短根性状的遗传。结果表明，RM1和RM2的短根性状均受单个位点稳性核基因（srt1srt1），并且RM1和RM2的短根基因是等位的。讨论了srt1基因在杂交稻和中子纯度快速鉴定中的应用。     

Inclusion body hepatitis caused by fowl adenovirus in broiler chickens in Japan, 2009-2010

From January 2009 to June 2010, many broiler chicks suddenly died without clinical signs. The mortality rates were from 1.2% to 17.0% in affected flocks. Inclusion body hepatitis (IBH) was detected in 13 prefectures (northern, eastern, western, and southern areas) in Japan. The livers were enlarged and pale. The bursa of Fabricius and thymus had not atrophied. Multifocal necroses of hepatocytes with basophilic intranuclear inclusions were seen in the liver. Eosinophilic intranuclear inclusion bodies in hepatocytes were rare. Focal necrosis of acinar cells with basophilic intranuclear inclusions was found in the pancreas. Basophilic intranuclear inclusion bodies were detected in intact surface epithelial cells of gizzard and epithelial cells of the small intestine. The intranuclear inclusions of liver, pancreas, gizzard, and small intestine were stained positively for immunohistochemistry of fowl adenovirus (FAV) antigen. Ultrastructurally, basophilic intranuclear inclusions consisted of viral particles approximately 70 nm in diameter and arranged in a crystalline array. FAV was isolated from the liver of chickens affected with IBH. The serotype of most isolates was 2. This study suggests that IBH produced by FAV is epidemic in broiler chicks in Japan and that the present cases occurred as the primary disease without the association of infectious bursal disease virus or chicken anemia virus.     

The prognostic significance of minimal residual disease in the early phases of chemotherapy in dogs with high-grade B-cell lymphoma

The prognostic significance of minimal residual disease (MRD) in the early phases of chemotherapy was examined in 36 dogs with multicentric high-grade B-cell lymphoma. Sequences of immunoglobulin heavy chain (IgH) gene fragments from lymphoma cells were amplified and used to design allele-specific primers and probes for real-time PCR. The dogs were treated with a 6-month modified version of the University of Wisconsin–Madison chemotherapy protocol (UW-25) and evaluated for the MRD level at weeks 6 and 11 of UW-25.Of the 31 dogs that remained on the protocol at week 11, 14 were found to be MRD negative (<10 tumour cells/10⁵ peripheral blood mononuclear cells [PBMCs]), whereas the other 17 were MRD positive (?10 tumour cells/10⁵ PBMCs). The progression-free survival of the dogs with MRD-negative status at week 11 (median, 337 days) was significantly longer than that of the MRD-positive dogs at the same time point (median, 196 days) (P = 0.0002). These results indicate the clinical significance of MRD as a prognostic marker in the early phase of chemotherapy.     

Shear tests of double shear plate connector joints in sugi—Japanese larch composite glulam beams

To study the shear strength of structural joints in sugi (Cryptomeria japonica D. Don) — Japanese larch (Larix kaempferi Carriere) composite glulam beams using structural connectors with double shear plates, shear tests were conducted on two types of joint (post-beam and girder-beam). Two types of the composite beam (240 and 300 mm depth) were prepared for the tests. Ordinary sugi glulam beam and Japanese larch glulam beam were also used as control specimens. The load—displacement curves of joints in composite beams were somewhere between those of sugi and Japanese larch glulam beams. The shear strength of joints in composite beams was higher than that in the sugi glulam beam control. However, the allowable loads of the joints in composite beams were lower than those in the sugi beam with 240 mm depth. Large variation of maximum load of the joints in the composite beams resulted in lower allowable load.     

Synthesis and herbicidal activity of new oxazinone herbicides with a long-lasting herbicidal activity against Echinochloa oryzicola

Chemical modification of the herbicide 1-[2-(benzothiazol-2-yl)isopropyl]-4-methyl-3-phenyl-5H-pyrrolin-2-one (MI-2826) has revealed a new oxazinone herbicide, 3-[2-(7-chlorobenzothiazol-2-yl)isopropyl]-2,3-dihydro-6-methyl-5-phenyl-4H-1,3-oxazin-4-one (MI-3069), for use in paddy fields. In comparing the phyototoxicity of the two herbicides to transplanted rice, the latter was superior to the former and kept the same predominant characteristic to control Echinochloa oryzicola Vasin for a long period of time owing to its long-lasting residual effect.     

Phytotoxic activity of Chinese violet (Asystasia gangetica (L.) T. Anderson) and two phytotoxic substances

Chinese violet (Asystasia gangetica (L.) T. Anderson) is a perennial invasive weed belonging to Acanthaceae. Leaves of this weed have been suggested to possess phytotoxic activity. However, phytotoxic substances in this weed have not yet been reported. Therefore, the present study investigated phytotoxic activity of Chinese violet extracts and phytotoxic substances. The extracts of Chinese violet leaves inhibited the root and shoot growth of cress, lettuce, alfalfa, barnyard grass, ryegrass, and timothy, where the level of inhibition increased with increasing extract concentrations. Bioassay‐guided separations of the extracts led to isolation of two phytotoxic substances, indole‐3‐carboxaldehyde and (6R,9S)‐3‐oxo‐α‐ionol. Indole‐3‐carboxaldehyde significantly inhibited the root and shoot growth of cress at concentrations ≥100 and 30 μmol L^?1, respectively, and concentrations of the substance required for 50% growth inhibition were 210 and 127 μmol L^?1 for cress roots and shoots, respectively. The other substance, (6R,9S)‐3‐oxo‐α‐ionol, was reported to have strongly inhibited cress roots and shoots. The present results suggest that Chinese violet contains two phytotoxic substances indole‐3‐carboxaldehyde and (6R,9S)‐3‐oxo‐α‐ionol, and those substances may play an important role in the phytotoxic activity of Chinese violet.     

Responsiveness of beef cattle (Bos taurus) to human approach,novelty, social isolation,restraint and trade‐offs between feeding and social companionship

This study investigated responsiveness of beef cattle to various environmental stimuli by subjecting 15–16 Japanese Black cows to five tests repeated twice. Within individual behavioral measures, cows were moderately (repeatability = 0.54–0.70) or highly (repeatability = 0.74–0.89) consistent in flight distance during grazing and resting in the human approach tests, maximum distance from the group pen and the number of total and different feed tub visits in the feeding–sociability trade‐off test, and unwillingness to enter the restraint, movement under restraint and flight speed after release from restraint in the social isolation and restraint test. By contrast, cows were not consistent in the latency to make the first contact and the number of contacts with novel object(s) in the novelty test (repeatability = 0.24–0.39). Across behavioral measures in different tests, cows showed no consistency (P ≥ 0.05) in any combinations of measures from the two human approach tests, the trade‐off test and the social isolation and restraint test. In conclusion, human approach (particularly during resting), feeding–sociability trade‐off and social isolation and restraint situations can be used for evaluating personality in Japanese Black cows, while the value of the novelty test needs to be reexamined.