インドの家畜頭数は莫大で，ほとんどの家畜所有者（99%）は伝統的な畜産方法に従い，農薬を使用していない牧草地で家畜，特に小型の反芻動物の飼育を行っている．飼料作物の栽培のため，いくつかの農薬がインドで使用されているが，その使用に関しては穀物やその他の関連農作物の知識に基づいているだけで，飼料作物に対する農薬使用についての認証データはない．カナダ，イギリス，イスラエル，およびその他のヨーロッパ諸国では飼料作物用に農薬登録が行われている．インドでは栽培可能な穀物，園芸作物，換金作物などに農薬が登録されているが，飼料作物に対する農薬の登録制度やガイドラインはない．したがって，それらの設定に必要な措置を講じる必要がある．この総説では，インドの飼料作物における農薬の使用とその現状について述べる．（文責：編集事務局）

新規水稲用除草剤シクロピリモレートの作用機構を解析した．シロイヌナズナをシクロピリモレートで処理すると白化症状が見られ，プラストキノンの減少に伴ってホモゲンチジン酸が顕著に蓄積した．また，植物中で代謝物のデスモルフォリノカルボニルシクロピリモレート（DMC）が検出された．このことから，シクロピリモレートまたはDMCが，プラストキノン生合成経路で4-ヒドロキシフェニルピルビン酸ジオキシゲナーゼの下流で働くホモゲンチジン酸ソラネシルトランスフェラーゼ（HST）活性を阻害すると予想された．そこで，シロイヌナズナのHSTを用いてin vitro試験を行ったところ，シクロピリモレートは弱いHST阻害活性を，DMCは強いHST阻害活性を有していることが明らかとなった．さらに，DMC類縁体のHST阻害活性と白化活性には正の相関が認められた．以上の結果は，シクロピリモレートおよびDMCの作用点はHSTであり，本剤は商用利用される除草剤における新規作用機作をもつことを示している．

オビヤスデ目エリヤスデ科ウチカケヤスデとヒメヨロイヤスデの防御物質である（2-ニトロエチル）ベンゼン，{(Z)-および（E）-2-ニトロエテニル}ベンゼンの生合成機序について，前駆体と想定される（Z）-および（E）-フェニルアセトアルドキシムとフェニルアセトニトリルの²H₅-ラベル体を²H₅-ブロモベンゼンから調製し，ヤスデ2種をそれぞれ倒立させ，強制的に飲ませる特異な経口投与法を開発して，標識実験した．その結果，2種ともにオキシムが前駆体であり，条件を整えられれば天然防御物質3成分の混合比と同様のラベル体生成比を再現できること，²H₅-ニトリルからも²H₅-防御物質の3成分を効率は悪いが生成できること，ニトリルとオキシムはヤスデ体内で相互に変換すること，GC/MS分析の選択イオンクロマトグラフ法で前駆体のニトリルとオキシムの存在をヤスデのヘキサン抽出物中に，散漫ではあるが，検出できる事を示した．

We cultivated Brassica rapa var. perviridis in soil mixed with four pesticides (fenobucarb, procymidone, flutolanil, and tolclofos-methyl) at different temperatures, day lengths, and soil water contents. We compared plants’ uptake and translocation abilities of the pesticides as affected by growth conditions. The root concentration factor (RCF) of pesticides tended to increase with rising temperature; however, but the influence of temperature on the transpiration stream concentration factor (TSCF) differed for each pesticide. The RCFs and TSCFs of pesticides were high for short days. The soil water content had little or no effect on the uptake and translocation of pesticides. These results showed that it is necessary to consider growth conditions, especially the temperature and day length in plant uptake models for these pesticides.

Ipfencarbazone exhibits excellent herbicidal activity against Echinochloa spp. and is safe for transplanted rice at a dose of 250 g a.i./ha. However, the effect of various environmental factors on its activity has not been verified. The present study evaluated the factors affecting the herbicidal activity of ipfencarbazone against Echinochloa spp. and its phytotoxicity to transplanted rice. The herbicidal activity and phytotoxicity of ipfencarbazone were barely affected by temperature, soil texture, water leakage, or flooding water depth. When an overflow was conducted artificially 6 hr after application, the herbicidal activity was stable. Furthermore, ipfencarbazone completely inhibited the emergence of Echinochloa spp. for 56 days regardless of the soil texture, water leakage and overflow conditions. When the period between application and reflooding was within 24 hr of herbicide application, the phytotoxicity of ipfencarbazone on transplanted rice was slight. These results suggest that ipfencarbazone shows stable efficacy in practical use.

A plant growth regulating agent “Fuji-one” has been used to control non-parasitic damping-off (Murenae disease) of rice seedlings. Its active ingredient, isoprothiolane (diisopropyl 1,3-dithiolan-2-ylidenemalonate, IPT), enhances root elongation of rice and Arabidopsis. To understand the mechanisms of IPT’s effect on root development, its effect on Arabidopsis root cells was investigated histologically. IPT at a lower concentration (12.5 µg/mL) had no effect on root cell elongation, whereas it enhanced cell division in the root meristem. Histological analysis using phytohormone-related mutants indicated that jasmonic acid and ethylene were involved in the enhanced cell division. In contrast, IPT at a higher concentration (75 µg/mL) suppressed both cell elongation and cell division, in which jasmonic acid and ethylene were not involved. In addition, root hair formation was suppressed by treatment with IPT. These analyses demonstrated that IPT (12.5 µg/mL) enhanced root elongation by activating cell division in a jasmonic acid- and ethylene-dependent manner.

We previously reported the strong insecticidal activity of a microbial secondary metabolite, pyripyropene A (PP-A), against aphids. Pyripyropenes (PPs) have been known to show weak feeding inhibition against lepidopteran pests, but their strong aphicidal activities were first reported in our former study. Here we investigated the details of the insecticidal property of PP-A. Our biological evaluation of PP-A found that it shows high insecticidal activities against some sucking pests, such as whiteflies, as well as aphids, and preferable biological profiles as agricultural insecticides. Furthermore, PP-A controlled aphids well under field conditions.

スピノサド抵抗性のヒラズハナアザミウマ系統を実験室内で確立した．抵抗性系統のLC₅₀値は1398.7 mg/Lであった．そのLC₅₀値は最も感受性の高い系統の約280倍であった．共力剤を用いた生物検定により，チトクロームP450，グルタチオン S-トランスフェラーゼ，カルボキシルエステラーゼなどの解毒分解酵素は抵抗性に関与していないことが示唆された．抵抗性系統ではニコチン性アセチルコリン受容体（nAChR）α6サブユニットの275番目のアミノ酸グリシンがバリンに変異していた．これらの結果は，ヒラズハナアザミウマのスピノサド抵抗性はnAChRの感受性の低下によってもたらされることを示唆している．

日本の黒ボク土を用いて，バッチ法および遠心法により測定された10種類の農薬の土壌吸着係数（K_d）を比較した．両手法で測定されたK_d値は，時間とともに上昇したが，試験期間を通してバッチ法で求めたK_d値が遠心法で求めたK_d値よりも大きい傾向にあった．両手法で求めたK_d値間の差は，土壌溶液中における農薬濃度推定に影響を及ぼし，バッチ法によるK_dに基づく推定結果は，実測値を過小評価する傾向にあった．

3種のペプタイボール，trichorizin HA II (1), HA V（2）およびHA VI（3）をTrichoderma harzianum HK-61株を植菌したオカラ培養物より単離した．それらの化学構造は，機器分析と化学誘導体化により確定した．Trichorzin類は，キュウリモザイクウイルスがササゲに感染するのをμMオーダーで阻害した．

We compared the risk of reselecting melanin biosynthesis dehydratase inhibitor (MBI-D)-resistant Pyricularia oryzae isolates between two treatment programs, a nursery box application of diclocymet and a rotational program in which nursery boxes received a non-MBI-D fungicide application and then later, in the field, a foliar application of a diclocymet and ferimzone mixture. Both were effective against panicle blast. However, the latter prevented the reselection of MBI-D-resistant isolates more effectively than the former.

To investigate root uptake and translocation of heptachlor and its degradates (cis-heptachlor epoxide and 1-hydroxychlordene) in soil, zucchini and tomato seedlings were transplanted to soil approximately four months after treatment with ¹⁴C-heptachlor. The results indicated that a relation between the root concentration factor and the log P_ow did not follow Briggs’ theory, probably due to the contribution of plant metabolism. It also appeared that a compound with a lower log P_ow tends to show higher mobility from root to shoot.

To clarify the properties of pesticide transformation products (TPs) for which the risk to aquatic organisms should be evaluated, I monitored the concentrations of paddy pesticides and their TPs in the Sakura River, Japan, during the rice-growing season in 2007–2010. I also conducted algal growth inhibition tests of herbicides and their TPs using a diatom and a green alga and acute toxicity tests of insecticides and their TPs using a caddisfly and a daphnid. Moreover, on the basis of the results of pesticide monitoring and toxicity tests, I attempted to evaluate the risk of these compounds to the riverine organisms as well as the risk of mixtures of insecticides and their TPs for caddisflies and cladocerans. The TPs were detected in the river water depending on the half-lives of the parent compounds and of the TPs in water and soil. The toxicities of the parent compound and its TPs may be related to their hydrophobicities and chemical structures. Some toxic and persistent TPs that formed rapidly in water and soil posed a risk to the organisms over a long period. The physicochemical properties and chemical structures of a parent compound and its TPs can be key factors in evaluating the pesticide TP risk to aquatic organisms in rivers.

We often encounter difficulties in analyzing pesticide residues in food, since the residue level to be measured is infinitesimal but the food samples may contain a variety of matrices, including interferences, for chromatographic analysis. Thus it is important to find out the key points to be checked in the extraction, purification, and determination steps of analysis. We have attempted to develop practical technologies for the analysis of pesticide residues in raw agricultural commodities based on the following studies: The effect of processing and cooking on pesticide residue levels in several crop samples (rice, wheat, soybean, and sesame) was investigated. The processing factor is useful to estimate the amount of exposure to each pesticide residue for risk assessment and is helpful in setting the maximum residue limits of processed foods. In addition, residue levels in the peel and pulp of watermelon, melon, and kiwi fruit samples were examined to confirm the differences in the distribution of residues. As a basic study, the effect of water-soaking pretreatment of powdered dry cereal on extraction efficiency was examined, and an optimal time for water-soaking was found. A recent study examined the ability of several new types of solid-phase extraction columns to remove matrices in brown rice samples and verified the effective purification method for each sample.

An aerobic dieldrin-degrading fungus, Mucor racemosus strain DDF, and two aerobic endosulfan-degrading fungal strains, Mortierella sp. strains W8 and Cm1-45, were isolated from soil contaminated with organochlorine pesticides. Strain DDF degraded more than 90% dieldrin during 10-days of incubation at 25°C and showed the production of a small amount of aldrin trans-diol. Moreover, strain DDF reduced levels of aldrin trans-diol while producing unknown metabolites that were determined to be aldrin trans-diol exo- and endo-phosphates. On the other hand, Mortierella sp. strains W8 and Cm1-45 degraded more than 70% and 50% of α and β-endosulfan, respectively, over 28 days at 25°C, in liquid cultures containing initial concentrations of 8.2 µM of each substance. Only a small amount of endosulfan sulfate, a persistent metabolite, was detected in the both cultures, while these strains could not degrade endosulfan sulfate when this compound was provided as the initial substrate. Both strains generate endosulfan diol as a first step in the degradation of endosulfan, then undergo further conversion to endosulfan lactone.