Characteristics of Leaf Water Potential and Photosynthetic Rate of Blueberry Plants Grown Under Drought Stress

Regulated deficit irrigation (RDI) involves inducing water stress during specific fruit growth phases by irrigating at less than full evapotranspiration. The objectives of this research were to study the effects of RDI perfomed at stage II of fruit growth and postharvest, on productivity of clingstone peaches, fruit quality as well as photosynthetic rate and midday leaf water potential. The research was conducted in a commercial clingstone peach (Prunus persica L. Batch cv. A-37) orchard in Greece. Trees were irrigated by means of microsprinklers and their frequency was determined using local meteorological station data and the FAO 56 Pennman-Monteith method. Photosynthetic rate was measured by a portable infrared gas analyzer. Midday leaf water potential was measured by the pressure chamber technique. During the years 2005 and 2006, the treatment RDII with irrigation applied at growth stage II of the peach tree did not affect productivity, fresh and dry mass of fruits. RDII reduced preharvest fruit drop in comparison to the control. RDII as well as the combined treatment RDII plus RDIP with irrigation applied at postharvest, at both years reduced shoot length of the vigorous shoots inside the canopy. RDII in comparison to the control increased the soluble solids content of the fruits and the ratio soluble solids/acidity. However it did not affect fruit acidity and fruit firmness. RDII as well as RDII plus RDIP in 2006 increased 'double' fruits and fruits with open cavity in comparison to the control and RDIP. Water savings were considerable and associated with the climatic conditions of each year.

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Arbuscular mycorrhizal influence on leaf water potential, solute accumulation, and oxidative stress in soybean plants subjected to drought stress

Journal of Experimental Botany ◽

10.1093/jxb/erh188 ◽

2004 ◽

Vol 55 (403) ◽

pp. 1743-1750 ◽

Cited By ~ 305

Author(s):

R. Porcel

Keyword(s):

Oxidative Stress ◽

Drought Stress ◽

Water Potential ◽

Leaf Water Potential ◽

Arbuscular Mycorrhizal ◽

Leaf Water ◽

Solute Accumulation ◽

Soybean Plants ◽

And Oxidative Stress

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Impact of Drought Stress on the Accumulation of Capsaicinoids in Capsicum Cultivars with Different Initial Capsaicinoid Levels

HortScience ◽

10.21273/hortsci.47.9.1204 ◽

2012 ◽

Vol 47 (9) ◽

pp. 1204-1209 ◽

Cited By ~ 26

Author(s):

Paongpetch Phimchan ◽

Suchila Techawongstien ◽

Saksit Chanthai ◽

Paul W. Bosland

Keyword(s):

Drought Stress ◽

Water Potential ◽

Leaf Water Potential ◽

Leaf Water ◽

Growth And Yield ◽

Yield Response ◽

Hot Pepper ◽

Environment Interaction ◽

Relative Water ◽

Drought Stress Condition

Capsaicinoids are the alkaloids in hot pepper that cause the sensation of heat when eaten and are affected by a genetic and environment interaction. Drought stress is well recognized as an environmental condition that influences capsaicinoid accumulation. This investigation identified the responses of capsaicinoid accumulation in hot pepper cultivars under drought stress condition. A total of nine cultivars with a different initial pungency level, i.e., low, medium, and high, was subjected to gradual drought stress during the flowering stage. Plants in this drought stress group were supplied with reduced water applications of 25%, 50%, and 75% by volume at 10, 20, and 30 days after flowering (DAF), respectively. Leaf water potential and relative water content were recorded to measure the level of drought stress. The results indicated that all cultivars were subjected to drought stress because of their decrease in leaf water potential and changes in physiological characteristics, e.g., growth and yield performance. In addition, leaf area and shoot-to-root ratio were good criteria for identifying hot pepper cultivars under drought stress because their responses were correlated with the stress level and yield components. Yield performances of the high pungency group did not decrease under drought stress, whereas those of the low pungency group did decrease. In conclusion, capsaicinoid levels increased for all cultivars studied when subjected to drought stress, except for the cultivars in the high pungency group. A yield response under drought stress for the medium pungency group varied and was not found to be associated with drought stress.

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Leaf Physiological Responses to Drought Stress and Community Assembly in an Asian Savanna

Forests ◽

10.3390/f10121119 ◽

2019 ◽

Vol 10 (12) ◽

pp. 1119

Author(s):

Thuy T. Nguyen ◽

Stefan K. Arndt ◽

Patrick J. Baker

Keyword(s):

Drought Stress ◽

Southeast Asia ◽

Water Potential ◽

Water Relations ◽

Leaf Water Potential ◽

Forest Type ◽

Adaptive Strategies ◽

Leaf Water ◽

Turgor Loss Point ◽

Drought Avoidance

Deciduous dipterocarp forest (DDF) is the most extensive forest type in continental Southeast Asia, but across much of its range is functionally more similar to tropical savannas than tropical forests. We investigated water relations and drought responses of the four dominant tree species (two Shorea and two Dipterocarpus species) of the DDF in central Vietnam to determine how they responded to prolonged periods of drought stress. We quantified leaf water relations in nursery- and field-grown seedlings of the four species and conducted a dry-down experiment on 258 seedlings to study leaf water potential and morphological responses of the seedlings following the drought stress. The two Shorea and two Dipterocarpus species differed significantly in leaf water potential at turgor loss point and osmotic potential at full turgor, but they showed similar responses to drought stress. All species shed leaves and suffered from stem loss when exposed to water potentials lower than their turgor loss point (approximately −1.7 MPa for Dipterocarpus and −2.6 MPa for Shorea species). Upon rewatering, all species resprouted vigorously regardless of the degree of leaf or stem loss, resulting in only 2% whole-plant mortality rate. Our results suggest that none of the four deciduous dipterocarp species is drought tolerant in terms of their water relations; instead, they employ drought-adaptive strategies such as leaf shedding and vigorous resprouting. Given that all species showed similar drought avoidance and drought-adaptive strategies, it is unlikely that seasonal drought directly influences the patterns of species assembly in the DDF of Southeast Asia.

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