AbstractSunflower (Helianthus annuu

Abstract

Sunflower (Helianthus annuus L.) is one of the most important oil-producing plants that it can tolerate short periods of water deficit
(WD). The objective of this study was to evaluate the effects of water stress on the physiological and agronomic characteristics of
four sunflower hybrids. A two-year field experiment was carried out using a randomized complete block design with four
replications and a split plot arrangement. The irrigation treatments were applied based on 60 mm (full-irrigated), 120 mm (moderate
water deficit) and 180 mm (extreme water deficit) of evaporation from the ‘class A’ pan evaporation. The results showed that water
deficit, compare to full-irrigated, significantly increased the activity of all antioxidant enzymes in leaves such as Superoxide
dismutase (SOD), Glutathione peroxidase (GPX), Glutathione reductase (GR) and Catalase (CAT). The correlation results showed
that the seeds number per head was main yield components associated to seed yield when sunflower plants were grown under the
full-irrigated and extreme water deficit. The results showed that the Euroflor and Allestar hybrids had highest seed yield in full and
limited irrigation condition, respectively. The correlation results showed that there was a high, positive and significant correlation
among seed yield and CAT in water irrigation deficit condition. Moreover, the GPX and CAT content can be used as a drought
tolerance index to selection tolerant genotypes under moderate and extreme water deficit conditions.

Keywords: CAT, GPX, GR, Helianthus annuus, Number of seeds per head, SOD, 1000-Seed weight.
Abbreviations: I
1
- well-irrigated; I
2
- moderate water deficit; I
- extreme water deficit; CAT- Catalase; GPX- Glutathione peroxidase;
GR- Glutathione reductase; ROS- reactive oxygen species; SOD- Superoxide dismutase; WD- water deficit.


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ผลลัพธ์ (อังกฤษ) 3:

Abstract Sunflower (Helianthus annuus L.) is one of the most important oil-producing plants that it can tolerate short periods of water deficit
(WD) .The objective of this study was to evaluate the effects of water stress on the physiological and agronomic characteristics of
four sunflower hybrids. A two-year field experiment was carried out using a randomized complete block design with four
replications and a split plot arrangement. The irrigation treatments were applied based on 60mm (full-irrigated), 120 mm (
moderate water deficit) and 180 mm (extreme water deficit) of evaporation from the 'class' A pan evaporation. The
results showed that water deficit, compare to full-irrigated, significantly increased the activity of antioxidant enzymes in leaves all such as Superoxide
dismutase (SOD), Glutathione peroxidase (GPX), Glutathione reductase (GR) and Catalase (CAT) .
The correlation results showed that the seeds number per head was main yield components associated to sunflower seed yield when plants were grown under the
full-irrigated and extreme water deficit. The Euroflor and results showed that the highest seed yield Allestar hybrids had in full and
Limited irrigation condition, respectively. The correlation results showed that there was a high, positive and significant correlation among
CAT in seed yield and irrigation water deficit condition. Moreover, the GPX CAT content and can be used as a drought tolerant genotypes
tolerance index to selection under moderate and extreme water deficit conditions.

Keywords: CAT, GPX, GR,annuus Helianthus, Number of seeds per head, SOD, 1000-Seed weight.
Abbreviations: I
1
- well-irrigated; I

2 - moderate water deficit; I
- Extreme water deficit; CAT - Catalase ; GPX - Glutathione peroxidase;
GR - Glutathione reductase; ROS - reactive oxygen species; SOD - Superoxide dismutase; WD - water deficit.


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