diplomsko delo
Mia Breberina (Avtor), Jasna Dolenc Koce (Mentor)

Povzetek

Senescenca je pomemben razvojni proces pri rastlinah. Je tudi pomemben dejavnik pridelave kmetijskih rastlin, saj omejuje biomaso in spreminja njihovo hranilno vrednost ter s tem vpliva na pridelek. Je uravnavan fiziološki proces, ki lahko poteka na različnih nivojih biološkega sistema: celic, tkiv, organov in celotne rastline. Pri senescenci listov potečeta programirana celična smrt in prenos hranil iz starajočih in odmirajočih tkiv v založna in prezimna tkiva. Izrabljene snovi pa se kopičijo v odmrlih celicah. Najbolj viden znak listne senescence je rumenenje listov, ki je posledica razgradnje pigmentno-proteinskih kompleksov v kloroplastih. Senescenco vzpodbujajo ali zavirajo različni biotski (virusi, glive, bakterije, rastlinojedci (žuželke)) in abiotski dejavniki (spremenjena temperatura, pomanjkanje hranil, suša, težke kovine, intenzivnost svetlobe). Ker staranje listov patogenim organizmom omogoča boljše izkoriščanje rastlinskih hranil, so okužbe s patogeni pogosto povezane z zapoznelim staranjem, kopičenjem hranil na mestih okužbe in rastnimi spremembami. Celoten potek, začetek in tudi zaključek senescence uravnavajo zapletene regulatorne poti in mehanizmi, na katere vplivajo notranji in zunanji dejavniki. Funkcionalne in transkriptomske genetske študije poročajo, da se v procesu staranja z genetskim reprogramiranjem spremeni izražanje številnih genov, povezanih s senescenco. Transkripcijski faktorji, kot so NAC, družina WRKY, MYB in AP2/ERF so znani kot ključni regulatorji, ki aktivirajo in uravnavajo gensko ekspresijo senescence v odgovor abiotskim in biotskim stresom, ki prizadanejo rastlino.

Ključne besede

senescenca;biotski stres;abiotski stres;endogeni dejavniki;eksogeni dejavniki;epigenetika;transkripcijski faktorji;rastline;odmiranje rastlin;razvojni proces rastlin;prenos hranil;

Podatki

Jezik: Slovenski jezik
Leto izida:
Tipologija: 2.11 - Diplomsko delo
Organizacija: UL BF - Biotehniška fakulteta
Založnik: [M. Breberina]
UDK: 601.4:577.21:581.1(043.2)
COBISS: 164395267 Povezava se bo odprla v novem oknu
Št. ogledov: 12
Št. prenosov: 2
Ocena: 0 (0 glasov)
Metapodatki: JSON JSON-RDF JSON-LD TURTLE N-TRIPLES XML RDFA MICRODATA DC-XML DC-RDF RDF

Ostali podatki

Sekundarni jezik: Angleški jezik
Sekundarni naslov: Regulation of plant senescence as a response to biotic and abiotic stress
Sekundarni povzetek: Senescence is an important developmental process in plants. It is also an important factor in agriculturally important plants, limiting their biomass and altering their nutritional value, thus affecting yields. It is a regulated physiological process that can take place at different levels of the biological system: cells, tissues, organs and the whole plant. Leaf senescence involves programmed cell death and transport of nutrients from ageing and dying tissues to storage and overwintering tissues. The used substances accumulate in the dead cells. The most visible sign of leaf senescence is yellowing of the leaves, which is a result of the breakdown of pigment-protein complexes in the chloroplasts. Leaf senescence is stimulated or inhibited by various biotic (viruses, fungi, bacteria, herbivores (insects)) and abiotic factors (change in temperature, nutrient deficiency, drought, heavy metals, light intensity). Leaf senescence allows pathogenic organisms to easier exploit plant nutrients therefore infections by pathogens are often associated with delayed senescence, nutrient accumulation at the infection sites and growth changes. The entire course, initiation and even termination of senescence is governed by complex regulatory pathways and mechanisms influenced by both internal and external factors. Functional and transcriptomic genetic studies report that the expression of many ageing-related genes is altered during the ageing process by genetic reprogramming. NAC, WRKY, MYB and AP2/ERF are known as key transcription factors that activate and regulate senescence gene expression in response to abiotic and biotic stresses affecting the plant.
Sekundarne ključne besede: senescence;biotic stress;abiotic stress;endogenous factors;exogenous factors;epigenetics;transcription factors;plants;plant death;developmental process in plants;nutrient mobilization;
Vrsta dela (COBISS): Diplomsko delo/naloga
Študijski program: 0
Konec prepovedi (OpenAIRE): 1970-01-01
Komentar na gradivo: Univ. v Ljubljani, Biotehniška fak., Študij biotehnologije
Strani: 1 spletni vir (1 datoteka PDF (VI, 19 str.))
ID: 19917033