园艺学原理光线的利用课件

1、1园艺学原理Chapter 6 光线 LIGHTBack to the LandRural poverty and food shortage are forcing nations and scientists to engineer a new Green Revolution. But theres a lot of lost ground to make up (Time, Oct. 26, 2009)23大 纲光合作用植物空间配置与光线截取关系白化作用色素效用光周性光量与植物生长光源及其用途光量测系统INTRODUCTIONPlants respond to light qualit

2、y, quantity, & photoperiod（光周）Light is electromagnetic radiation（电磁波辐射）(fig. 7-2)WaveParticles: photons （光子） 45Fig. 7.2 Electromagnetic spectrum电磁波长400-700nm范围为可视光Fig. 7.2 Electromagnetic spectrum6光线属于电磁波辐射Fig. 7.1 Light is a transverse electromagnetic wave7光合作用过程（附图5-12, 图7.10）光吸收色素：叶绿素、辅助色素（如类胡萝卜素

3、）光能传递：激发能(excitation energy)波长渐长，能量减少光化学反应反应中心：PS1, PS2氧化还原反应电子传递ATP, NADPH2形成暗反应Calvin cycleCO2固定碳水化合物形成8(Nobel, P. S. 1999. Physical and Environmental Plant Physiology.)采光天线9Fig. 7.10 Basic concept of energy transfer during photosynthesisPhotosynthesis12H2O + light + 6CO2 C6H12O6 + 6O2 + 6H2OChlor

4、oplasts (fig. 7-15)Process of photosynthesisLight rxCarbon dioxide fixation3 carbon pathway4 carbon pathwayCrassulacean acid metabolism （景天酸代谢）(CAM) （table 5-1)1011类囊体Fig. 7.15 Transmission electron micrograph of a chloroplast from pea (Pisum sativum)121314Ornamental cabbageCornJade plant 1516Spacin

5、g & orienting plants for light interception（光截取）Optimal spacingFrequently planted at the ideal spacing for mature plantsInterplanting （间作）: plants w/ upright habits & spreading plants w/n or between rows is efficient Programmed dense planting（计划性密植）: dense initially, thinned laterWeed controlContain

6、erized plants（盆栽植物）Hydroponical growing（水耕） system: automatically adjusting spacing17Spacing & orienting plants for light interceptionDouble, triple or wide rows utilize space more efficiently for backyard gardeners (fig. 7-19)Landscape plants must be properly spaced Other methods for fruit treesPru

7、ning（修剪）Dwarf rootstocks（矮性砧木）Plant growth retardants（植物生长抑制剂）Manipulating difference between night & day temp (DIF)18Orientation（方向）Often-debated subjectGreenhouse orientationEast-west above 40NNorth-south below 40NGutter-connected （连栋） greenhouseNorth-southOpen gardenThe tallest plants to the nort

8、h, and the shortest to the south19Pruning plants for light interceptionFruit treesThinning-out pruning （ 疏删修剪） (fig. 5-8, 5-9, 5-10)Open-center training （开心整枝）: peach (fig. 5-9, 5-10)Objective Constant yieldGood-quality fruitsOrnamentalsHedge （绿篱）: wider on the bottom than the top (fig. 5-12, 5-13)E

9、spalier （树篱）(fig. 5-14)Topiary （装饰剪）(fig. 5-14)Bonsai （盆景）(fig. 5-15)2021Thinning-out cuts(5-8) 2223Maximize light interception(5-10)2425Hedge(5-12)26An improperly pruned hedgeThe resulting holes impair the desired visual effect.(5-13)2728Etiolation （白化）Plants often become etiolated in response to a

10、 blanching （去光、暗化） treatmentSymptoms (fig. 5-16)White to yellowish stems & leavesSpindly growth of stemsExtreme elongation of internodesFormation of seedling hooks （钩）Role of hook (fig. 5-19)Use Cauliflower (fig. 5-20), table onion (fig. 5-21)Vegetative propagation: cutting （扦插）, layering （压条）(fig.

11、5-22) 29303132hook3334宜兰三星青葱35宜兰三星青葱高畦栽培36Effect of pigments- carotenoidsCarotenoids （类胡萝卜素）Accessory（辅助） pigments for photosynthesisPhotoprotection （光保护）Impart color to flower, fruits, seeds 37Cryptochromes （隐藏色素） & PhototropinsBlue-light photoreceptorsCryptochromesControl stem elongation（如附图18.4；1

12、8.6）, cotyledon & leaf expansion, daily rhythms, & floweringPhototropins （趋光素）: phototropism （向旋光性）auxin383918.4 Phototropism in wild type (A) and mutant (B) Arabidopsis seedlings40蓝光抑制生长Phytochromes （光敏素）General charactersH. A. Bothwick & S. B. Hendricks of USDARed (R) or far-red (FR) effect on let

13、tuce seed germination （附图17.2）(table 5-2)Phytochrome interconversions (fig. 5-23)The highest amounts exists in meristematic tissues & their newly formed daughter cells.Seed DormancyPhotoblastic Stimulated: carrot, gloxinia (大岩桐）, weeds Inhibited: tomatoUnaffected: peas & sweet corn4142434445Phytochr

14、omes (Cont. 1)Branching & stem elongation（分支与茎伸长）R: short internodes, vigorous axillary bud（腋芽） growth (fig. 5-24)Ecological significance (fig. 9.4, 5-25, 5-26)Anthocyanin（花青素） productionA typical high irradiance reaction mediated by phytochromeEffect of light on coloring of eggplant (fig. 5-29) app

15、le, peach4647红光多于远红外线叶片高效率吸收可视光，但吸收较少远红外线Fig. 9.4 Optical properties of a bean leaf495051Photoperiodism （光周性）W. W. Garner & H. A. Allard (1920)A response to day lengthDarkness is critical（附图25.19）Phytochrome is the photoreceptor（光接受器）（附图25.23）Each species has its own requirement for a minimum number

16、 of inductive photoperiodsFloweringFormation of storage organsStem elongation Temperate trees & woody shrubs5253夜间才是关键54夜间才是关键5556FloweringJuvenile adult3 distinct classesDay neutral plants (DNP)Initiate flowers under a wide range of day lengthExampleCucumber, everbearing （四季开花）strawberry, sweet cor

17、nQuantitative long-day plants Petunia（牵牛花）, carnationQuantitative short-day plants Tomato, Rieger begonia（秋海棠）57Flowering (Cont. 1)Long-day plants (LDP)Summer-flowering plantsEvening primrose （报春花）, spinach (fig. 5-31)Short-day plants (SDP)Late summer- or fall-flowering plantsCocklebur (Xanthium pen

18、nsylvanicum)（仓耳）, chrysanthemum, kalanchoe （厚叶属）, poinsettia（附图25.18）585960dandelion(蒲公英)6162Flowering (Cont. 2)Photoperiodic control of floweringRevolutionize the floriculture industryChrysanthemum can be programmed to flower at any desired time at any location Critical day length vary among crops

19、& cultivarsManipulate critical day length either by controlling lighting or by providing darkness LightingIncandescent lamps are commonly used (fig. 5-34, 5-35)Night interruption （暗期中断）by lighting for 2-4 hr in the middle of night6364Cuttings for vegetative propagation(扦插苗营养繁殖)6566Flowering (Cont. 3

20、)Darkening Black cloth or plastic is pulled over the crop in the late afternoon & again in the early morning (fig. 5-36)Alternating day lengths（变换日长）SD followed by LDBell flower （吊钟花）, creeping white cloverLD followed by SDKalanchoe & some lilies6768(fig. 5-36)Formation of storage organsStimulated b

21、y SDTubers of potato, Jerusalem artichoke（菊竽）, scarlet runner bean （红花菜豆）, BegoniaStimulated by LDBulbs of onion, early garlicTuberous root formation of Dahlia occur under any day length, but greater root under SD (fig. 5-38)6970Potato tubers from in response to short days.71Formation of tuberous ro

22、ots on dahlia is accelerated by short days.(fig. 5-38)Stem elongationRunner （走茎）formation Stimulated by LD: strawberryStimulated by SD: spider plant （吊兰）(fig. 5-19)7273spider plant （吊兰）(fig. 5-19)74Temperate trees & woody shrubsStimulated by SDFall coloration of leavesLeaf fall (abscission)Onset of

23、cold hardnessOnset of dormancyPhytochrome is involved 75Light quantity & qualityLight quantity & photosynthesisLight compensation point （光补偿点）Light saturation point （光饱和点）（附图9-7）Vary w/ plant spp. & growing condition (附图 9-8）Shade tolerance （耐阴性）Sun & shade leavesLeaf area index （叶面积指数）Acclimatizati

24、on（驯化） of foliage plants7677阳性与阴性植物在不同亮度之光合成速率Shade tolerance （耐阴性）Category (table 5-3)Nearly all vegetables & fruit crops grow best in full sunMust select the genotype to fit the location (fig. 5-41)Many understory plants（树冠下层植物） are quite shade-tolerant & intolerant of full sunlightFoliage plants

25、are produced under shading materials (fig. 5-42, 5-43) 787980ImpatiensazaleasPlants that grow well and flower in shaded locations81美国加州家庭庭院阳性植物828384海南观叶植物生产圃8586Sun & shade leaves （阳性与阴性叶）Comparison (table 5-4)Shade leaves under bright sunlightLeaf scorch（焦化）(fig. 5-44)Photoinhibition （光抑制）, photod

26、ecomposition（光分解）878889Leaf scorch（焦化）(fig. 5-44)90Leaf area index （叶面积指数）Leaf area index (LAI)Ratio of the area occupied by all the leaves to the surface of ground that the plant coversLAI as related to the plant productivity (附图)Leaf orientation (vertical) as related to yield91Fig. 9.4 Optical pro

27、perties of a bean leaf叶片高效率吸收可视光93Fig. Crop growth rate (CGR) of soybean communities as a function of the leaf area index (LAI) (Loomis, R.S., D. J. Connor. 1992. Crop Ecology, p.42)94Acclimatization of foliage plants （观叶植物驯化）Foliage plants frequently are raised outdoors in the full sun & must be pr

28、operly acclimatized to prevent leaf-loss before being used for interior-scapingManipulate light, temperature, watering, & nutritionLight is the most importantLower light levels to 40%-80% for 5 to more than 10 wkGrown under 40% shadePlaced indoors for decoration light is the limiting factor (fig. 5-

29、46)9596Light sources & their useLight sourceSunlightElectric lampsHigh-Intensity Discharge (HID) LampsFluorescence Lamps （荧光灯）Incandescent Lamps （钨丝灯）97High-intensity discharge (HID) lampsTypes of lampsMercury (Hg) Metal halide (MH)Sodium w/ high- or low- pressureProperty Spectral quality (fig. 5-34

30、)Big ballasts（基座） & reflectors (fig. 5-47)More expensive but longer life expectancy9899Fluorescence lamps （荧光灯）Types of lampsCool white: more commonWarm whiteSpectral property (fig. 5-34)Used for seed germination & tissue cultureLower quantity of light & overcome by extending day length100101Incande

31、scent lamps （钨丝灯）Used primarily for photoperiodic controlEmit too much heatLow in blue end of the spectrum (fig. 5-34)Exhibit tall, succulent growth charactersHigh in red end of the spectrumUse bulbs w/ internal reflectors (fig. 5-35) 102Systems for measuring lightTerminologyFlux: flow of a substance or transfer of ene