Differences in salinity tolerance for growth and water‐use efficiency in some amaranth(Amaranthusspp.) genotypes

In three separate experiments, the growth and water use of salinized citrus rootstock seedlings and grafted trees were modified using different growth substrates, elevated CO2, or 50% shade screen under field conditions. By reanalyzing previously published data, we tested the hypothesis that salinity tolerance in citrus can be characterized as the ability to maintain low levels of leaf Cl− accumulation through high plant growth and high water use efficiency (WUE) under saline conditions. Well-irrigated salinized seedlings of the relatively salt-sensitive Carrizo citrange [Carr (Citrus sinensis × Poncirus trifoliata)] were grown in sand, clay, or a peat-based soilless media. Salinity stress reduced plant growth and water use. Leaf Cl− concentration was negatively related to plant growth, but leaf Cl− increased with transpiration rate in low-saline treatments. In a second experiment using salinized seedlings of the relatively salt-tolerant Cleopatra mandarin [Cleo (Citrus reticulata)] grown along with Carr seedlings with or without elevated CO2, leaf Cl− was negatively related to growth and to shoot/root dry weight ratio, but was positively related to water use such that leaf Cl− was negatively related to leaf WUE. In a third experiment using salinized 2-year-old ‘Valencia’ orange (C. sinensis) trees grafted on Cleo or Carr rootstocks and grown with or without shadecloth, leaf Cl− was positively related to leaf transpiration as both were higher in the spring than in the fall, regardless of rootstock or shade treatment. Overall, leaf Cl− was positively related to water use and was negatively related to leaf WUE. High growth, low water use, and consequently, high WUE of salinized citrus were related to low leaf Cl−. Such relationships can be used as indicators of salinity tolerance.

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Salinity Tolerance of Cleopatra Mandarin and Carrizo Citrange Citrus Rootstock Seedlings Is Affected by CO2 Enrichment during Growth

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.131.1.24 ◽

2006 ◽

Vol 131 (1) ◽

pp. 24-31 ◽

Cited By ~ 47

Author(s):

Francisco García-Sánchez ◽

J.P. Syvertsen

Keyword(s):

Gas Exchange ◽

Plant Growth ◽

Water Use Efficiency ◽

Water Use ◽

Salinity Tolerance ◽

Leaf Growth ◽

Carrizo Citrange ◽

Citrus Rootstock ◽

Use Efficiency ◽

Cleopatra Mandarin

Three-month-old citrus rootstock seedlings of the Cl- excluder Cleopatra mandarin (Citrus reticulata Blanco) and the Cl- accumulator Carrizo citrange [C. sinensis (L.) Osb. × Poncirus trifoliata L.] were fertilized with nutrient solution with or without additional 50 mm NaCl and grown at either ambient CO2 (360 μL·L-1) or elevated CO2 (700 μL·L-1) in similar controlled environment greenhouses for 8 weeks. Elevated CO2 increased plant growth, shoot/root ratio, leaf dry weight per area, net assimilation of CO2, chlorophyll, and water-use efficiency but decreased transpiration rate. Elevated CO2 decreased leaf Ca2+ and N concentration in non-salinized Cleopatra. Salinity increased leaf Cl- and Na+ in both genotypes. Carrizo had higher concentrations of Cl-but lower Na+ in leaves than Cleopatra. Salinity decreased plant growth, shoot/root ratio, net gas exchange, water use, and root Ca+2 but increased root N in both genotypes regardless of CO2 level. Neither salinity nor elevated CO2 affected leaf chlorophyll fluorescence (Fv/Fm). Carrizo had higher Fv/Fm, leaf gas exchange, chlorophyll, N, and Ca2+ than Cleopatra. Salinity-induced decreases in leaf osmotic potential increased leaf turgor especially at elevated CO2. The increase in leaf growth at elevated CO2 was greater in salinized than in nonsalinized Carrizo but was similar in Cleopatra seedlings regardless of salt treatment. In addition, salinity decreased water-use efficiency more at elevated CO2 than at ambient CO2 in Cleopatra but not in Carrizo. Elevated CO2 also decreased leaf Cl- and Na+ in Carrizo but tended to increase both ions in Cleopatra leaves. Based on leaf growth, water-use efficiency and salt ion accumulation, elevated CO2 increased salinity tolerance in the relatively salt-sensitive Carrizo more than in the salt-tolerant Cleopatra. In salinized seedlings of both genotypes, Cl- and Na+ concentration changes in response to eCO2 in leaves vs. roots were generally in opposite directions. Thus, the modifications of citrus seedling responses to salinity by the higher growth and lower transpiration at elevated CO2 were not only species dependent, but also involved whole plant growth and allocations of Na+ and Cl-.

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Growth, gas exchange and water use efficiency of the facultative hemiparasite Rhinanthus minor associated with hosts differing in foliar nitrogen concentration

Physiologia Plantarum ◽

10.1034/j.1399-3054.1993.890110.x ◽

1993 ◽

Vol 89 (1) ◽

pp. 64-70 ◽

Cited By ~ 13

Author(s):

W.E. Seel ◽

R.E. Cooper ◽

M.C. Press

Keyword(s):

Gas Exchange ◽

Water Use Efficiency ◽

Water Use ◽

Nitrogen Concentration ◽

Foliar Nitrogen ◽

Use Efficiency ◽

Rhinanthus Minor

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Increasing intrinsic water-use efficiency over the past 160 years does not stimulate tree growth in southeastern China

Climate Research ◽

10.3354/cr01526 ◽

2018 ◽

Vol 76 (2) ◽

pp. 115-130 ◽

Cited By ~ 5

Author(s):

G Guo ◽

K Fang ◽

J Li ◽

HW Linderholm ◽

D Li ◽

...

Keyword(s):

Water Use Efficiency ◽

Water Use ◽

Tree Growth ◽

Southeastern China ◽

The Past ◽

Intrinsic Water Use Efficiency ◽

Use Efficiency

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A comparative appraisal of urea super granule application in raised bed and prilled urea application in conventional planting for transplanted boro rice (Oryza sativa)

JOURNAL OF ADVANCES IN AGRICULTURE ◽

10.24297/jaa.v6i1.5388 ◽

2016 ◽

Vol 6 (1) ◽

pp. 822-832

Author(s):

Halim Mahmud Bhuyan ◽

Most. Razina Ferdousi ◽

Mohammad Toufiq Iqbal ◽

Ahmed Khairul Hasan

Keyword(s):

Water Use Efficiency ◽

Water Use ◽

N Fertilizer ◽

Deep Placement ◽

Prilled Urea ◽

Planting Methods ◽

Weed Infestation ◽

Use Efficiency ◽

Raised Bed ◽

Boro Rice

Utilization of urea super granule (USG) with raised bed cultivation system for transplanted boro (winter, irrigated) rice production is a major concern now days. A field experiment was conducted in the chuadanga district of Bangladesh to compare the two cultivation methods: deep placement of USG on raised bed with boro rice, and prilled urea (PU) broadcasting in conventional planting. Results showed that USG in raised bed planting increased grain yields of transplanted boro rice by up to 18.18% over PU in conventional planting. Deep placement of USG in raised bed planting increased the number of panicle m-2, number of grains panicle-1 and 1000-grains weight of boro rice than the PU in conventional planting. Better plant growth was observed by deep placement of USG in raised bed planting compared to PU in conventional planting. Sterility percentage and weed infestation were lower on USG in raised bed planting compared to the PU in conventional planting methods. Forty seven percent irrigation water and application time could be saved by USG in raised bed planting than PU in conventional planting. Deep placement of USG in bed saved N fertilizer consumption over conventional planting. Water use efficiency for grain and biomass production was higher with deep placement of USG in bed planting than the PU broadcasting in conventional planting methods. Similarly, agronomic efficiency of N fertilizer by USG in bed planting was significantly higher than the PU broadcasting in conventional planting. This study concluded that deep placement of USG in raised bed planting for transplanted boro rice is a new approach to achieve fertilizer and water use efficiency as well as higher yield and less water input compared to existing agronomic practices in Bangladesh.

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