Fakülteler / Faculties

Permanent URI for this communityhttps://hdl.handle.net/11727/1395

Browse

Filters

2015 - 20162

Settings

Author: search.filters.author.Ekmekci, Yaseminsearch.filters.applied.f.rights: search.filters.rights.info:eu-repo/semantics/closedAccess

Search Results

Now showing 1 - 2 of 2
  • No Thumbnail Available
    Item
    Are the Photosynthetic Performance Indexes and the Drought Factor Index Satisfactory Selection Criterion for Stress?
    (2015) Cicek, Nuran; Arslan, Ozlem; Culha-Erdal, Sekure; Eyidogan, Fusun; Ekmekci, Yasemin; ACA-9644-2022
    This study was conducted to assess the drought stress and the recovery responses of twenty one chickpea cultivars (Cicer arietinum L.) grown in Turkey. 20-day-old seedlings were subjected to mild drought conditions for 7 days, recovery period of 3 days followed. Then a moderate stress period of 10 days was applied, followed by recovery period of 4 days. Finally, severe stress period of 13 days was applied, followed by recovery period of 5 days. Drought stress treatments were observed to have an adverse effect on photosynthetic efficiency, but also malondialdehyde, total chlorophyll (app. half of cultivars) and carotenoid contents of leaf tissue have increased when compared with their controls. 21 chickpea cultivars were classified into four groups; highly tolerant, tolerant, less tolerant and sensitive, according to the drought factor index (DFI), the values calculated by photosynthetic performance index (PItotal). Only four cultivars recovered from severe drought stress conditions. Aziziye and Diyar 95 cultivars may be suggested to be cultivated in drought-prone areas. In general, the present results indicate that: 1. PItotal and DFI are very satisfactory selection criterion for drought stress. 2. The recovery processes of plants exposed to environmental constraints should be investigated to make the right selection.
  • No Thumbnail Available
    Item
    Does Sublethal Temperature Treatment Provide Any Tolerance in Tetraploid Wild and Durum Wheat Seedlings Exposed to Lethal Heat Stress?
    (2016) Eyidogan, Fusun; Terzioglu, Serpil; Ekmekci, Yasemin; ACA-9644-2022
    In this study, the effects of sublethal heat application before lethal heat treatment on thermotolerance mechanisms of tetraploid two wild wheats (Aegilops biuncialis and Aegilops cylindrica), and two durum wheats (Triticum turgidum L. cv. Kiziltan-91 and Harran-95) have been investigated. Eight-day-old seedlings were exposed sublethal heat pretreatment followed by lethal heat treatment [39 +/- 1 degrees C for 24h afterwards 50 +/- 1 degrees C for 1 h (T1)] and lethal heat treatment [50 +/- degrees C for 1 h (T2)]. When plants exposed to direct lethal temperature (T2), seedling lengths were significantly reduced in all genotypes. The sub-lethal treatment enabled the seedlings to tolerate the lethal effects of heat stress with respect to seedling length but this effect was not observed in Kiziltan-91 cultivar. T1 and T2 applications caused a decrease in relative water content in leaves of all genotypes. Total chlorophyll and carotenoid contents of tetraploid wild species were significantly decreased after all heat treatments. The sub-lethal heat pretreatment caused an accumulation of total chlorophyll and carotenoid contents in only Kiziltan-91 cultivar. Ae. cylindrica was found to be sensitive to heat but its degree of protection was higher than other genotypes. This tetraploid wild genotype probably withstands heat with better upregulating protective mechanisms.