@article{
author = "Božić, Manja and Stanojević, Aleksandra and Marković, Ksenija and Ignjatović-Micić, Dragana and Nikolić, Dragana and Milivojević, Marija and Nikolić, Ana",
year = "2021",
abstract = "Maize is one of the most important crop species worldwide, but also extremely
susceptible to the effects of increasingly higher temperatures and drought during the
summer and its flowering and grain filling stage. Different strategies are being utilized to
ensure a satisfying yield potential and quality even in the extremely unfavourable
environmental conditions, which are the result of climate change. Some of them are
cropping pattern changes and sowing alterations, including earlier sowing. Since this
implies the exposure to suboptimal temperatures during early developmental stages, it
leads to a demand for developing maize lines tolerant to low temperatures during these
stages. This research focuses on the first phase of germination, imbibition.
Maize tolerance to low temperatures is a complex trait that includes different mechanisms
and strategies that all work together to ensure adaptation and survival, such as cell
membrane changes, antioxidative system activation, etc. Additionally, the low
temperature response of different maize inbreds varies substantially, so recognizing the
different ways in which they respond to low temperatures during imbibition and other
earlier stages of development is crucial. To accomplish this, seeds of two maize inbred
lines of contrasting susceptibility to low temperatures were selected and exposed to
control (20° C) and low temperature (8°C) conditions during the first 24h of imbition andthen further analyzed to assess their response. This included germination and tetrazolium
assays; ascertaining membrane integrity by evaluating cell leakage and lipid peroxidation;
determining the antioxidative capacity by assessing superoxide dismutase (SOD) and
catalase (CAT) activity; and expression analysis of four genes included in the low
temperature response (gibberellin insensitive dwarf 1 gibberellin receptor, gid1; fatty acid
desaturases 2 and 6, fad2 and fad6; plastid-lipid-associated 2 protein, pap2).
The results showed that, while there is not a significant difference in their germination
rate, they differ in their survival rate, with more seeds of the tolerant genotype surviving
the low temperature period. Significant differences between them were found in cell
leakage (p<0,01), as well as gid1(p<0,05) and fad6 (p<0,05) gene expression assays. The
present research brings light to our understanding of the effect of low temperatures on the
first germination stage, - imbibition. It highlights the importance of choosing the right
inbreds for earlier sowing and points to certain routes that could be taken for improving
and accelerating the breeding process for low temperature tolerance., Kukuruz je usev od izuzetne važnosti za poljoprivredu, koji se takođe odlikuje značajnom
osetljivošću na visoke temperature i sušu tokom letnjih meseci, odnosno tokom faze cvetanja i
nalivanja zrna. Jedna od strategija obezbeđivanja zadovoljavajuće produktivnosti i prinosa
kukuruza, uprkos nepovoljnim uslovima životne sredine, jeste ranija setva. Ipak u tom slučaju su
biljke kukuruza izložene suboptimalnim temperaturama u ranim fazama razvića, što stvara
potrebu za razvojem linija tolerantnih na niske temperature u tim fazama, što je i fokus ovog
istraživanja. Odgovor kukuruza na niske temperature je kompleksan i uključuje niz različitih
mehanizama i strategija koje obezbeđuju opstanak, a takođe zavisi i od samog genotipa, faze
razvića, itd. Iz tog razloga, odgovor kukuruza na niske temperature (8°C) je posmatran tokom
faze imbibicije, kod dva genotipa, i to na nivou promena genske ekspresije (gid1; fad2; fad6;
pap2), aktivnosti antioksidativnih enzima (SOD, CAT), integriteta ćelijskih membrana, stopa
germinacije, kao i samog preživljavanja. Rezultati ukazuju da postoje statistički značajne razlike
između genotipova kada je reč o stopi preživljavanja, integritetu ćelijskih membrana i ekspresiji
gena gid1i fad6 (p<0,05). Ovo istraživanje ukazuje na moguće mehanizme aklimatizacije na
niske temperature tokom faze imbibicije i ističe značaj odabira odgovarajućih linija za raniju
setvu.",
publisher = "Belgrade : Serbian Genetics Society",
journal = "Genetika",
title = "Physiological and gene expression changes during imbibition in maize seeds under low temperature conditions",
volume = "53",
number = "3",
pages = "1147-1165",
doi = "10.2298/GENSR2103147B"
}
