Thaum xaiv cov khoom cog hauv cov lus piav qhia rau cov nroj tsuag tshwj xeeb, ntau tus neeg nyob hauv lub caij ntuj sov pom hais txog ntau txoj hauv kev pollination lossis tus kheej pollination. Cov no yog cov ntsiab lus uas peb txhua tus tau kawm hauv tsev kawm ntawv hauv botany zaj lus qhia. Tab sis tsis muaj coob tus twb nco ntsoov tias lawv txhais li cas. Cia peb ua kom peb nco thiab nco txog hom pollination nyob rau hauv cov nroj tsuag thiab lawv cov tseem ceeb lom. Thiab tib lub sijhawm peb yuav pom tias yog vim li cas qee qhov ntawm peb cov nroj tsuag cog hauv lub tebchaws lossis ntawm windowsill tsis txi txiv.
Cov khoom nruab nrog cev ntawm cov nroj tsuag siab dua
Ib lub paj yog hloov kho qhov twg spores thiab gametes tsim. Cov nroj tsuag siab dua (angiosperms) muaj cov paj uas tsis yooj yim nrog ntau yam hloov mus rau ntau hom pollination. Lub paj, sib txawv hauv cov ntsiab lus, sib txuas cov txheej txheem ntawm kev sib deev thiab kev sib deev. Cov khoom tseem ceeb ntawm lub paj yog nws qhov kev ua me nyuam - txiv neej androecium (stamens) thiab poj niam gynoecium (pistil nrog zes qe menyuam, style thiab stigma). Paj tuaj yeem yog bisexual (muaj ob qho tib si pistil thiab stamens) thiabtib-poj niam txiv neej (muaj ib tug pistil los yog stamens). Lwm qhov ntawm lub paj yog ntau yam thiab muaj cov haujlwm tshwj xeeb.
Kev sib ntsib ntawm stamens thiab pistil
Pollination yog txheej txheem ntawm kev hloov paj ntoos los ntawm stamens mus rau stigma ntawm pistil. Yog tsis muaj qhov no, kev yug me nyuam ntawm cov nroj tsuag, tsim ntawm txiv hmab txiv ntoo thiab noob yog tsis yooj yim sua. Nyob rau hauv tus txheej txheem ntawm evolutionary txoj kev loj hlob, cov nroj tsuag tau tsim ntau txoj kev los mus ua kom tiav qhov kev hloov no siv biotic thiab abiotic yam ntawm xwm. Hauv ecology, ob hom pollination yog qhov txawv:
- Kev hloov paj paj ntawm ib lub paj mus rau ib qho pistil ntawm lwm tus. Cov txheej txheem no hu ua cross-pollination, lossis xenogamy. Nws yog nqa tawm los ntawm biotic (kab, noog, puav) thiab abiotic (cua, dej) yam.
- Autogamy (self-pollination). Qhov no yog qhov hloov ntawm pollen ntawm stigma los ntawm ib lub paj. Autogamy tsis zoo li cov ntawv qus.
Cov no yog hom pollination uas tuaj yeem hloov pauv ntawm qee cov nroj tsuag.
Tus kheej-pollination tej yam kev mob
Tab sis ib qho yuav tsum tau ua rau kev siv ntawm tus kheej-pollination yog bisexuality ntawm paj. Kev sib tsoo ntawm tus kheej-pollination ntawm paj tsis yog qhov txawv. Tab sis nws tuaj yeem tshwm sim tsuas yog thaum paj paj noob hlis thiab pestle yog lub cev sib xws. Hauv ntau cov nroj tsuag, paj ntoos tsis tawg rau hauv lub paj paj ntoos, uas yog qhov txwv tsis pub rau cov ntoo khaub lig-pollinated. Muaj ob peb yam uas ua rau random autogamy. Tsis tu ncua ntawm tus kheej-pollination ntawm cov nroj tsuag (piv txwv li, peas, taum) tuaj yeem muaj lub zog nqus. Hauv qhov no, pollenntog rau ntawm stigma nyob rau hauv qhov kev txiav txim ntawm lub ntiajteb txawj nqus. Nyob rau hauv lwm yam mob, tus kheej-pollination tshwm sim raws li kev sib cuag autogamy - lub stamens nyob rau hauv kev sib cuag nrog lub stigma ntawm pistil. Cov paj paj ntoo nyob hauv nruab nrab ntawm lub paj tuaj yeem yog cov dej ntws thiab cov kab me me (thrips) uas nyob hauv lub paj. Hauv qee cov nroj tsuag, cov txheej txheem tshwm sim nyob rau hauv lub paj thiab tshem tawm tag nrho cov muaj peev xwm ntawm cross-pollination.
xaiv tus kheej pollination
Ib yam ntxwv ntawm hom autogamy no yog qhov muaj cov xwm txheej tsis ruaj khov uas tsis pom zoo hla kev pollination. Hom kev pollination tus kheej no muaj nyob rau hauv cereals, sundew, thiab feather nyom. Nyob rau hauv cov nroj tsuag no, nyob rau hauv drought los yog nyob rau hauv qis kub, unisexual paj yog tsim, thiab nyob rau hauv sov thiab ntub huab cua - bisexual. Hla-pollination ntawm cov nroj tsuag no yog nqa tawm nrog kev pab los ntawm cua, thiab nyob rau hauv tej yam kev mob ntawm kev nyuaj siab nyob rau hauv kev siv ntawm xws pollination, nws yog ib qho tsim nyog yuav tau mus rau qhov chaw rau nws tus kheej pollination.
Tus nqi hloov pauv
Tus kheej-pollination hauv cov ntsiab lus evolutionary muaj lub ntsiab lus tsis zoo. Raws li cov tswv yim niaj hnub no, evolution yuav tsum muaj kev hla dawb, uas yog muab los ntawm kev sib hloov ntawm cov paj ntoo. Nws yog qhov no uas ua rau kom muaj ntau haiv neeg ntawm alleles (the degree of expression of a gene) in population. Thiab tus kheej-pollination, ntawm qhov tsis sib xws, ua rau homozygosity (uniformity) ntawm alleles. Tab sis nyob rau hauv qee qhov xwm txheej, nws tus kheej pollination tuaj yeem ua rau muaj kev sib cais ntawm cov ntaub ntawv tshiab, kev sib cais thiab kho nyob rau hauv cov pejxeem ntawm alleles uas muab cov cim zoo rau cov nroj tsuag. Raws nraim ntawmQhov no yog qhov zoo evolutionary tseem ceeb ntawm alternation ntawm autogamy thiab xenogamy.
Tus kheej-pollinating nroj tsuag
Hauv cov nroj tsuag zoo li no, kev hloov pauv ntawm paj ntoos feem ntau yog nqa tawm hauv lub paj tsis qhib (piv txwv li, hauv taum thiab peas) lossis nyob rau lub sijhawm ntawm lub raj tsis qhib nplooj (barley). Peas, taum, barley, nplej, oats, txiv lws suav, eggplants thiab ntau lwm tus yog suav hais tias yog tus kheej-pollinators los ntawm cov qoob loo ua liaj ua teb. Vim li cas lawv suav? Vim tias nws tus kheej pollination tsis tuaj yeem ua tiav, nws yeej ib txwm muaj peev xwm qhia paj paj ntawm lwm cov nroj tsuag. Txawm tias kaw buds yog qee zaum gnawed los ntawm kab thiab nqa paj ntoos los ntawm lwm yam nroj tsuag! Dab tsi yog cov yam ntxwv ntawm tus kheej-pollinators? Cov no yog cov nroj tsuag uas muaj bisexual paj, loj feathery stigmas thiab ntau paj paj. Tsis tas li ntawd, lawv cov paj tsis muaj cov paj zoo nkauj, cov paj ntoo thiab cov ntxhiab tsw qab ntxiag.
Tus kheej pollination hauv violets
Hauv qhov xwm txheej, violets yog hla-pollinated thiab autogamous. Peb cov violets sab hauv tsev yog cov khoom ntawm kev mob siab ua haujlwm ntawm cov neeg yug tsiaj. Lawv muaj xws li cov qauv ntawm stamens thiab pistil uas hla-pollination yam tsis muaj kev cuam tshuam tib neeg yog yuav luag tsis yooj yim sua. Pollination tshwm sim txawm nyob rau hauv ib tug tsis qhib bud, thiab tsuas yog ib tug neeg mob amateur nrog kev pab los ntawm cov tswv yim tshwj xeeb muaj peev xwm pollinate violets ntawm txawv xim rau yug me nyuam ntau yam tshiab. Ua tsaug rau cov neeg txhawb siab rau ntau yam ntawm cov paj no dai peb lub qhov rais sills!
Parthenocarpic dib
Kev yug me nyuam niaj hnub muaj ntau yamdib, ob qho tib si tus kheej-pollinated (parthenocarpic) thiab pollinated los ntawm kab. Cov nroj tsuag no yog bred tshwj xeeb rau kev cog qoob loo thaum ntxov hauv tsev cog khoom uas tsis muaj cov pollinators ntuj. Thaum muas cov noob, koj yuav tsum tau nres ntawm kev nyeem qhov zoo ntawm ntau yam, vim tias ob qho tib si tus kheej-pollinated thiab cross-pollinated ntau yam muaj lawv qhov zoo thiab qhov tsis zoo.
Pollination hauv cereals
Oats, rye, nplej, millet, barley yog cov neeg sawv cev ntawm kev ua liaj ua teb cereals. Cov paj muaj 2 lemmas, 2 pellicles, peb stamens thiab ib tug pistil. Lawv self-pollinate nyob rau hauv unopened paj. Thaum lub paj qhib, hla-pollination yog tsis yooj yim sua.
Tus kheej pollination hauv txiv ntoo
Txawm hais tias feem ntau cov txiv hmab txiv ntoo muaj paj uas muaj ob qho tib si pistils thiab stamens, nws tus kheej fertilization tsis suav nrog feem ntau. Yog vim li cas yog lub sij hawm sib cais maturation ntawm stamens thiab pistil. Tias yog vim li cas koj tuaj yeem nce cov qoob loo, piv txwv li, cherries, los ntawm kev cog ob peb tsob ntoo nyob ze. Tab sis nyob rau hauv ntau yam bred artificially, nws tus kheej-pollination yog txais tos. Ib qho piv txwv yog nectarines. Tab sis tsis txhob cia siab tias yuav loj hlob ib tsob nroj tsim tau los ntawm cov noob. Nyob rau hauv xws li hybrid cov ntaub ntawv, tiam tom ntej muaj kev nyuaj siab hybrid - ib tug txo nyob rau hauv viability thiab yield.
Kev xaiv thiab tus kheej pollination
qhov tshwm sim no yog siv dav hauv kev cog qoob loo. Peb paub tias nws tus kheej fertilization thiab hla ntawm cov kab mob sib ze ua rau kev hloov pauvCov noob rau hauv lub xeev homozygous thiab ua rau txo qis hauv kev muaj peev xwm thiab kev tsim khoom, thiab tom qab ntawd mus rau degeneration. Cov txheej txheem txuas ntxiv ntawm kev hloov pauv uas sib sau ua ke, feem ntau ntawm cov uas tsis zoo thiab tsis zoo, yog qhov ua rau muaj kev tsim txom. Hauv cov nroj tsuag nrog ntoo khaub lig-pollination, cov kev hloov pauv no nyob rau hauv lub xeev heterozygous thiab tsis tshwm sim lawv tus kheej hauv txhua txoj kev. Nrog rau tus kheej pollination, qhov tshwm sim ntawm lawv txoj kev hloov mus rau homozygote nce ntau zaus, tab sis lawv tsis nyob hauv cov pej xeem vim kev tshem tawm ntuj. Self-pollination hauv kev yug me nyuam yog siv los ua ib qho cuab yeej los tsim cov kab ntshiab (homozygous) nrog cov yam ntxwv ruaj khov. Txawm hais tias qhov txo qis hauv kev tsim khoom, tom qab hybridization, qhov tshwm sim ntawm heterosis feem ntau tshwm - lub zog ntawm hybrids los ntawm ntau yam nrog nws tus kheej pollination. Qhov tshwm sim no yog hu ua interline hybridization, thiab hauv khw muag khoom peb tuaj yeem pom cov noob hybrid nkaus xwb (lawv tau cim nrog lub cim F1). Nyob rau hauv thawj tiam, hybrids outperform ntshiab kab nyob rau hauv cov nqe lus ntawm yield, tab sis nyob rau hauv lub tom ntej tiam, cov nyhuv ntawm lub zog ntawm hybrids ploj.
