Herbicides and Plant Physiology. Andrew H. Cobb

1.4 Expected rates of photosynthesis (PS) by C₃ and C₄ plants at (a) ...Figure 1.5 Effect of black‐grass density on the growth and yield of winter w...

      2 Chapter 2Figure 2.1 Typical cumulative cash flow for a successful new product.Figure 2.2 Modern herbicide screening.Figure 2.3 Information needed to optimise herbicide development.Figure 2.4 Herbicide mode of action.Figure 2.5 Relationship between herbicide mobility, log K_ow and pK_a. (After ...Figure 2.6 Herbicide metabolism in relation to selectivity. Points A–D are s...

      3 Chapter 3Figure 3.1 The upper leaf surface of fat hen (Chenopodium album L.) as shown...Figure 3.2 A generalised scheme of cuticle structure.Figure 3.3 An overview of the three primary pathways of epicuticular wax bio...Figure 3.4 Effect of logP_ow and ΔlogP on foliar uptake through the cuticle v...Figure 3.5 Schematic representation of droplets on a leaf surface in the abs...Figure 3.6 Structure of ethoxylated trisiloxanes in Silwet L‐77. When n = 2,...Figure 3.7 Accumulation of a weak acid (pK_a 4.0) within root cells by the io...Figure 3.8 Cross‐section of a dicotyledonous root, showing the position of t...Figure 3.9 Structures of a typical phenoxyalkanoic acid (2,4‐D) and an arylo...Figure 3.10 The quatemary salt of 2,4‐DFigure 3.11 Examples of some low volatility esters used in herbicide formula...Figure 3.12 Butoxy‐methyl ethyl ester of fluroxpyr.Figure 3.13 The formulation of glyphosate.Figure 3.14 Structure of amido propylamines, where R1 can be C8/C10, COCO or...

      4 Chapter 4Figure 4.1 Bioactivation of inactive pro‐herbicides to active molecules.Figure 4.2 A diagrammatic representation of plant P450 and P450 reductase en...Figure 4.3 The haem‐binding sequence that is characteristic of all P450s.Figure 4.4 Nomenclature for naming P450 genes.Figure 4.5 The main reactions carried out by cytochrome P450 monooxygenases ...Figure 4.6 Metabolism of bentazone in tolerant plant species.Figure 4.7 A schematic representation of the different phases of herbicide m...Figure 4.8 Cereal crop selectivity to a theoretical herbicide in the presenc...Figure 4.9 Structures of tetcyclasis, 1‐aminobenzotriazole and tridiphane....Figure 4.10 A generalised summary of safener and synergist action.

      5 Chapter 5Figure 5.1 Leaf structure in Galium aparine (cleavers). (A) Leaf arrangement...Figure 5.2 Structural (A) and functional (B) models of Photosystem II. Numbe...Figure 5.3 Structural (A) and functional (B) models of Photosystem I. Number...Figure 5.4 Schematic representation of the light‐harvesting and photosystem ...Figure 5.5 DCPIP decolourisation in the presence of functioning thylakoids....Figure 5.6 Proposed interaction between plastoquinone (A) and atrazine (B) w...Figure 5.7 The D1 polypeptide. (A) Schematic arrangement of the protein in t...Figure 5.8 The structures of atrazine and BW314.Figure 5.9 Damage–repair cycle in Photosystem II.Figure 5.10 Detail of the environment surrounding the lipophilic group in th...Figure 5.11 Examples of herbicide classes in the serine family.Figure 5.12 Essential features of the phenol‐type ‘histidine’ herbicides....Figure 5.13 Structures of the ‘histidine’ family of herbicides: the hydroxyb...Figure 5.14 A selection of herbicides that inhibit Photosystem II electron f...Figure 5.15 How paraquat and diquat act at Photosystem I to give rise to act...Figure 5.16 Structures of new Photosystem II herbicides.Figure 5.17 Carbamylation of lysine activates RuBisCo.Figure 5.18 Bonding orbitals in diatomic oxygen.Figure 5.19 Generation of singlet oxygen by photosensitisers.Figure 5.20 Superoxide generation and detoxification at Photosystem I. PQ, p...Figure 5.21 The fates of solar energy absorbed by the thylakoid light‐harves...Figure 5.22 The chain reaction of thylakoid lipid peroxidation.Figure 5.23 Ultrastructural symptoms following treatment with photosynthetic...Figure 5.24 A characteristic fluorescent transient or Kautsky curve induced ...Figure 5.25 Structures of two chalcone derivatives as potential inhibitors o...

      6 Chapter 6Figure 6.1 Structures of the major chlorophylls and carotenoids.Figure 6.2 Biosynthesis of δ‐aminolaevulinic acid (ALA) and porphobilin...Figure 6.3 An overview of porphyrin biosynthesis in the presence (dashed lin...Figure 6.4 Structure of saflufenacil, indicating structure‐activity relation...Figure 6.5 Protection of chlorophyll (Chll) by carotenoids (car).Figure 6.6 The xanthophyll cycle.Figure 6.7 Carotenoid biosynthesis.Figure 6.8 Structures of five commercialised inhibitors of phytoene desatura...Figure 6.9 The role of plastoquinone in carotenoid biosynthesis and its rege...Figure 6.10 Synthesis of homogentisic acid from tyrosine.Figure 6.11 Structures of HPPD inhibitors referred to in the textFigure 6.12 Nitisinone.Figure 6.13 Metabolism of isoxaflutole in crops and weeds.Figure 6.14 Metabolism of sulfentrazone in soybean.Figure 6.15 Pathways of carotenoid and plastoquinone biosynthesisFigure 6.16 Structures of herbicides that inhibit 1‐deoxy‐D‐xylulose‐5‐phosp...

      7 Chapter 7Figure 7.1 Ethylene evolution by scentless mayweed following application of ...Figure 7.2 Effect of exogenous auxin (IAA) on growth (solid curves) and ethy...Figure 7.3 The control of auxin concentration in vivo.Figure 7.4 Auxin biosynthesis and metabolism (see text for details)Figure 7.5 Structures of indole‐3‐butyric acid (IBA), 4‐chloroindole‐3‐aceti...Figure 7.6 A topographic model of the auxin receptor viewed from the side. T...Figure 7.7 Structures of the methyl ester of dichlorprop (which controls dic...Figure 7.8 A simplified model describing how auxin concentration controls ge...Figure 7.9 A speculative view of the immediate consequences of auxin binding...Figure 7.10 Approximate differences in electrical potential and pH in a plan...Figure 7.11 Dose–response curves for auxin‐induced proton‐efflux.Figure 7.12 The chemiosmotic model for polar auxin (IAA) transport in xylem ...Figure 7.13 The structure of diflufenzopyr (BAS 662 H).Figure 7.14 Effect of clopyralid (100 g a.i. ha⁻¹) on rate of photosyn...Figure 7.15 Typical symptom development of auxin‐type herbicides. Plants of Figure 7.16 The use of autoradiography to study the translocation patterns o...Figure 7.17 Pathways of metabolism of (A) MCPA and (B) 2,4‐D.Figure 7.18 Bioactivation of MCPB in susceptible broadleaf weeds.Figure 7.19 The effect of β‐oxidation on phenoxyacids containing an odd...

      8 Chapter 8Figure 8.1 Fatty acid biosynthesis in plants. ACP, Acyl carrier protein.Figure 8.2 (A) Diagrammatic representation of the three functional domains o...Figure 8.3 Structures of herbicides acting as very long‐chain fatty acid bio...Figure 8.4 Inhibition of fatty acid thioesterases in the chloroplast. ACP, a...Figure 8.5 Inhibition of auxin‐induced proton‐efflux by diclofop‐methyl (DM)...Figure 8.6 Percentage ¹⁴C‐activity recovered from plants of Setaria viridis ...Figure 8.7 Biosynthesis of jasmonyl‐L‐isolencine (JA‐ile) and the jasmonic a...Figure 8.8 Structures of some molecules involved in Jasmonic acid biosynthes...Figure 8.9 Metabolism of diclofop‐methyl in wheat and wild oat.

      9 Chapter 9Figure 9.1 Overview of amino acid biosynthesis. R₅P, Ribulose 5‐phosphate; P...Figure 9.2 The structures of glutamate and the glutamine synthase inhibitors...Figure 9.3 The two‐step process in the catalysis of glutamine synthesis by g...Figure 9.4 The structure of glyphosate.Figure 9.5 Biosynthesis of aromatic amino acids. EPSP, 5‐Enoylpyruvate shiki...Figure 9.6 The X‐ray crystal structure of Escherichia coli EPSP synthase. On...Figure 9.7 Structure of 7‐deoxy‐sedoheptulose.Figure 9.8 Shikimate pathway highlighting DQS and EPSPS as target enzymes fo...Figure 9.9 A simplified version of tyrosine pathways in plants (modified fro...Figure 9.10 Biosynthesis of branched‐chain amino acids.Figure 9.11 Structure of 2‐cyclohexene‐D‐glycine, an inhibitor of threonine ...Figure 9.12 Structure of aspterric acid, a carotane‐type sesquiterpene, an i...Figure 9.13 Sulphonylurea metabolism in various crops.Figure 9.14 Differences in the metabolism of imidazolinones between wheat (t...Figure 9.15 Proposed histidine biosynthesis pathway in plants.Figure 9.16 The structures of histidine, aminotriazole, IGP and three triazo...

      10 Chapter 10Figure 10.1 The mitotic cell cycle.Figure 10.2 An overview of the main events in the plant cell cycle (see text...Figure 10.3 Factors affecting tubulin polymerisation and depolymerisation. M...Figure 10.4 The structures of pendimethalin, CA₁ and CA₂.Figure 10.5 The effect of treatment with 0.1 g active ingredient (a.i.) L⁻¹...

      11 Chapter 11Figure 11.1 A simplified scheme for cellulose synthesis in plants.Figure 11.2 Categorisation of cellulose biosynthesis inhibitors according to...Figure 11.3 5‐tert‐Butyl‐carbamoyloxy‐3‐(3‐trifluoromethyl)phenyl‐4‐thiazoli...Figure