Borya nitida Labill.—An Australian Species in the Liliaceae With Desiccation-tolerant Leaves

Borya nitida, a perennial tufted herb, grows in south Western Australia as a pioneer plant codominant with lichens on exposed rock outcrops, and on bare sands with low water-holding capacity and rapid drainage. The mature leaves of the plant are capable of reviving after desiccation; they develop drought tolerances of 0% relative humidity (RH) under field conditions. The rate of drying is critically important for the development of desiccation tolerance. Drought-avoidance mechanisms (possibly related to the xeromorphic features of the plant) slow the rate of dehydration sufficiently for the development of full drought tolerance which requires completion of a time-dependent tolerance-endowing process in the range of water potential around 96% RH (90-98%), as well as avoidance of a slower time-dependent injurious process at water potentials of 75% RH and above. Non-senescent leaves that fulfil both requirements remain viable at water potentials below 50% RH for years. Dry viable leaves are yellow, owing to the loss of chlorophyll during the former process. Induction of drought tolerance at moderate water stress has been reported in other species, but Borya is remarkable for the extreme rapidity of the process and the degree of tolerance developed.

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Thirty years of genetic progress combined with seed ethylene priming improved drought resistance of wheat through long-term drought stress memory

10.21203/rs.3.rs-380527/v1 ◽

2021 ◽

Author(s):

Hongkun Yang ◽

Wenmei Hu ◽

Jiarong Zhao ◽

Xiulan Huang ◽

Ting Zheng ◽

...

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Grain Yield ◽

Drought Resistance ◽

Crucial Role ◽

Soil Water Deficit ◽

Stress Memory ◽

Drought Avoidance ◽

Water Holding

Abstract Knowledge of short-term physiological adaption of wheat to soil water deficit is well understood, but little is known about seed ethylene priming effect on long-term drought stress memory of dryland winter wheat. The 42 leading and new cultivars released between 1992 to 2017 were subjected to drought (45% Field water-holding capacity), and well-watered (75% Field water-holding capacity) conditions aim to screen cultivars with contrasting drought resistance and grain yield. Seeds primed with ethylene were subjected to both PEG-8000 and pure water to uncover ethylene-induced stress memory at both physiological and organ levels. Results showed that the soil water deficit (45%FC) that occurred at the tillering stage resulted in 3.2% to 67.4% yield loss for 42 cultivars, which was determined mainly by the decrease in the fertile spike. Seed ethylene priming maintained leaf water by reducing root volume and dry weight, which played a crucial role in drought avoidance. Seed ethylene priming decreased malondialdehyde content by regulating auxin and abscisic acid signaling, reactive oxygen species scavenging capability, and osmotic regulation, which plays a crucial role in drought tolerance. Seed ethylene priming improved drought tolerance of the wheat through metabolic modification of carbon metabolism, glutathione metabolism, and phenylpropanoid biosynthesis . The seed ethylene priming induced long-term stress memory that improved tillering capacity and reduced wheat spikelets abortion, which provided extra 0.3 t ha -1 of grain yield. These results suggested that seed ethylene priming allowed the recall of long-lasting stress defensive memory, increasing grain yield by both drought avoidance and drought tolerance.

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Genetic Basis of Drought Resistance at Reproductive Stage in Rice: Separation of Drought Tolerance From Drought Avoidance

Genetics ◽

10.1534/genetics.105.045062 ◽

2005 ◽

Vol 172 (2) ◽

pp. 1213-1228 ◽

Cited By ~ 250

Author(s):

Bing Yue ◽

Weiya Xue ◽

Lizhong Xiong ◽

Xinqiao Yu ◽

Lijun Luo ◽

...

Keyword(s):

Drought Tolerance ◽

Drought Resistance ◽

Genetic Basis ◽

Reproductive Stage ◽

Drought Avoidance

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Screening for Drought Tolerance in Thirty Three Taro Cultivars

Notulae Botanicae Horti Agrobotanici Cluj-Napoca ◽

10.15835/nbha46110950 ◽

2018 ◽

Vol 46 (1) ◽

pp. 65-74 ◽

Cited By ~ 8

Author(s):

José F.T. GANANÇA ◽

José G.R. FREITAS ◽

Humberto G.M. NÓBREGA ◽

Vanessa RODRIGUES ◽

Gonçalo ANTUNES ◽

...

Keyword(s):

Drought Tolerance ◽

Agronomic Traits ◽

Yield Stability ◽

Yield Potential ◽

High Yield ◽

Potential Yield ◽

Local Cultivars ◽

Drought Avoidance ◽

Drought Tolerant ◽

Long Duration

Taro [Colocasia esculenta (L.) Schott] is a root crop which is an important staple food in many regions of the world, producing 10.5 million tonnes on 1.4 million hectares a year. The crop is cultivated in wet (rain fed) or irrigated conditions, requiring on average 2,500 mm water per year, and in many countries it is cultivated in flooded plots. It is estimated that taro production could decrease by 40% as a result of the increase in drought and other severe events. In this work, thirty three accessions, including local cultivars, selected and hybrid lines were submitted to long duration drought stress and screened for tolerance. Twelve physiological, morphological and agronomic traits were measured at harvest, and subject to multivariate analysis. Stress indices, Water Use Efficiency and Factorial Analysis were useful for discriminating accessions regarding drought tolerance and yield stability, and drought tolerant and susceptible cultivars were identified. Our results confirm that different taro cultivars have different drought avoidance and tolerance strategies to cope with water scarcity. Better yield performers minimised biomass and canopy loss, while tolerance was observed in cultivars that presented low potential yield, but efficiently transferred resources to enhance corm formation. Among the 33 accessions, two local cultivars showed high yield stability and could be considered as suitable parents for breeding programs, while two others are well adapted to drought, but with overall low yield potential.

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Water relations characteristics of Alnusrubra and Populustrichocarpa: responses to field drought

Canadian Journal of Forest Research ◽

10.1139/x88-178 ◽

1988 ◽

Vol 18 (9) ◽

pp. 1159-1166 ◽

Cited By ~ 14

Author(s):

S. R. Pezeshki ◽

T. M. Hinckley

Keyword(s):

Water Relations ◽

Root Development ◽

Osmotic Potential ◽

Stomatal Closure ◽

Leaf Age ◽

Leaf Water ◽

Black Cottonwood ◽

Red Alder ◽

Mature Leaves ◽

Water Potentials

Water relations of red alder (AlnusrubraBong.) and black cottonwood (populustrichocarpa Torr. & Gray) were studied in the field during the 1980, 1981, and 1982 growing seasons. Stomatal closure in response to drought was noted in both species; however, the following major differences were noted between the 1980 observations and those of 1981 and 1982; (i) stomatal conductance was greater in black cottonwood than in red alder, whereas the reverse was noted in 1980, and (ii) even though 1981 and 1982 were warmer and drier than 1980, corresponding changes in predawn and minimum leaf water potentials were not observed. These differences were attributed to greater root development, particularly in black cottonwood, in the second (1981) and third (1982) years following establishment (1980) of these species. Leaf age and drought exposure were observed to influence osmotic potentials in both species. Values of the osmotic potential at saturation varied from −0.80 to −1.03 MPa in newly mature leaves of red alder and from −1.00 to −1.26 MPa in similarly aged leaves of black cottonwood. Values in mature leaves ranged from −0.84 to −1.27 MPa in red alder and from −1.37 to −1.75 MPa in black cottonwood. There appeared to be a continued decrease in osmotic potential in both species throughout the growing season, a response associated with leaf development and drought exposure. Throughout the study, significantly lower values of osmotic potential at saturation and at the turgor loss point were found in black cottonwood than in red alder. Consequently, black cottonwood had a potential adaptive advantage in comparison with red alder. Leaf shedding in response to drought was noted mainly in red alder. Generally, both of these riparian species exhibited slight to moderate capabilities of surviving exposure to low leaf water potentials and moderate to excellent capabilities of stomatal closure under conditions potentially leading to low water potentials. The role played by root development in the differences observed among the years and between black cottonwood and red alder is discussed.

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Drought tolerance of juvenile and mature leaves of a deciduous dwarf shrub Vaccinium myrtillus L. in a boreal environment

PROTOPLASMA ◽

10.1007/s00709-009-0096-x ◽

2010 ◽

Vol 241 (1-4) ◽

pp. 19-27 ◽

Cited By ~ 16

Author(s):

Erja Taulavuori ◽

Marjaana Tahkokorpi ◽

Kari Laine ◽

Kari Taulavuori

Keyword(s):

Drought Tolerance ◽

Vaccinium Myrtillus ◽

Dwarf Shrub ◽

Mature Leaves ◽

Boreal Environment ◽

Vaccinium Myrtillus L

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Effect of Water Stress on Stomatal Conductance and Leaf Water Relations of Leaves Along Current-Year Branches of Peach

Functional Plant Biology ◽

10.1071/pp9890549 ◽

1989 ◽

Vol 16 (6) ◽

pp. 549 ◽

Cited By ~ 4

Author(s):

SL Steinberg ◽

MJ Mcfarland ◽

JC Miller

Keyword(s):

Water Stress ◽

Stomatal Conductance ◽

Water Potential ◽

Water Status ◽

Stomatal Closure ◽

Water Flux ◽

Leaf Water ◽

Leaf Water Status ◽

Mature Leaves ◽

Water Potentials

A gradation, that reflects the maturity of the leaves, exists in the leaf water, osmotic and turgor potential and stomatal conductance of leaves along current and 1-year-old branches of peach. Predawn leaf water potentials of immature folded leaves were approximately 0.24 MPa lower than mature leaves under both well-watered and dry conditions. During the daytime the leaf water potential of immature leaves reflected the water potential produced by water flux for transpiration. In well- watered trees, mature and immature unfolded leaves had a solute potential at least 0.5 MPa lower than immature folded leaves, resulting in a turgor potential that was approximately 0.8 MPa higher. The turgor requirement for growth appeared to be much less than that maintained in mature leaves. As water stress developed and leaf water potentials decreased, the osmotic potential of immature folded leaves declined to the level found in mature leaves, thus maintaining turgor. In contrast, mature leaves showed little evidence of turgor maintenance. Stomatal conductance was lower in immature leaves than in fully mature leaves. With the onset of water stress, conductance of mature leaves declined to a level near that of immature leaves. Loss of turgor in mature leaves may be a major factor in early stomatal closure. It was concluded that osmotic adjustment played a role in maintenance of a leaf water status favorable for some growth in water-stressed immature peach leaves.

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The effect of drought on the photosynthetic apparatus condition in some Ficus Carica cultivars

Plant Biology and Horticulture: theory, innovation ◽

10.36305/2019-2-151-109-119 ◽

2019 ◽

pp. 109-119

Author(s):

T. B. Gubanova ◽

R. A. Pilkevich ◽

A. A. Kharchenko ◽

I. V. Bernatsky

Keyword(s):

Drought Tolerance ◽

Photosynthetic Apparatus ◽

High Sensitivity ◽

Photochemical Activity ◽

Fluorescence Induction ◽

Water Holding Capacity ◽

Ficus Carica ◽

Resistant Cultivar ◽

Chlorophyll Fluorescence Induction ◽

Water Holding

The results of field and laboratory studies of drought tolerance in some Ficus carica cultivars of various origins are presented. It has been found out that under the conditions of the Southern Coast of the Crimea, the cultivar Sabrutsiya Rozovaya is characterized by high drought tolerance. Low resistance to dehydration was noted in the cultivars Vladimirska Krupna, Pomoriyskiy 6, Franziana Biella. It was revealed that in August, a decrease in water holding capacity occurs in all the studied cultivars. Using Chlorophyll Fluorescence Induction (CFI) method, an integrated assessment of the photosynthetic apparatus in the leaves of Ficus carica cultivars under conditions of simulated wilting is given. It has been demonstrated that drought is the cause of decrease in the photosynthesis light phase efficiency, the part of chlorophyll involved in the transfer of energy from light harvesting antenna complexes to reaction centers and the enhancement of non-photochemical photo quenching. A resumption of photosynthetic activity was observed with the normalization of leaf water supply in the resistant cultivar Sabrutsiya Rozovaya and the medium-resistant cultivar Iyulskiy. In the cultivars characterized with low drought tolerance, Vladimirska Krupna, Pomoriyskiy 6 and Ranniy iz Sozopol, the resumption of the water content in leaves was followed by a decrease in the variable fluorescence and photochemical activity of PS 2, which indicates further stress development in these cultivars and high sensitivity of their photosynthetic apparatus to dehydration. During the fruit ripening, on the background of water holding capacity decrease, water deficit in leaf tissues within 20-25% results in irreversible disturbances in the photosynthetic apparatus activity in Ficus carica cultivars that is proved by a decrease in the viability index below the vitality norm and may adversely affect the preparation of plants for transition to a state of rest.

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198 EVALUATION OF DROUGHT TOLERANCE OF Fragaria chiloensis CLONES WITH POTENTIAL AS LOW-MAINTENANCE ORNAMENTAL GROUNDCOVERS

HortScience ◽

10.21273/hortsci.29.5.457e ◽

1994 ◽

Vol 29 (5) ◽

pp. 457e-457

Author(s):

Ann Marie VanDerZanden ◽

J. Scott Cameron

Keyword(s):

Gas Exchange ◽

Drought Tolerance ◽

Control Group ◽

Total Biomass ◽

Stress Cycle ◽

Chl A ◽

Water Potentials ◽

Fragaria Chiloensis ◽

Fourth Derivative ◽

Recovery Cycles

Fragaria chiloensis (Linnaeus) Is a viable. low maintenance alternative to groundcovers currently available in the ornamental landscape industry. There is considerable genetic variability within this specks for leaf morphology, growth and flowering habits as well as drought tolerance. Clones collected from 11 coastal sites in CA and OR were compared for drought tolerance after two Imposed water stress\recovery cycles. Predawn water potential, gas exchange, chlorophyll (chl) content, fourth derivative spectroscopy, carbon isotope discrimination, and total biomass production were evaluated and significant clonal differences were observed. Predawn water potentials after the first stress cycle ranged from -35.0 MPa to -6.5 MPa. Clones I05, DNT and G19 had highest predawn water potentials and gas exchange rates after both stress cycles. In the control group, I05 and DNT had higher levels of chl a, chl b, total chl and chl a\b. After the first stress cycle, clones DNT and I05 had the highest chl a\b ratio, however, after the second stress event there were no differences In any chl parameters. Varying adaptive abilities observed may suggest differential use in the landscape.

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