Improved photosynthesis by leaf nutrient content enhances water use efficiency in Juniperus tibetica along elevation gradients above 4000 m a.s.l

A field experiment was conducted in sandy clay loam soil during winter season of 2012-13. The lowest weed dry weight and the highest nutrient content were recorded under 80 mm CPE. Significantly the highest grain and straw yield, total nutrients uptake, and the highest consumptive use of water (57.8 cm), rate of water use (4.52 mm/day), water use efficiency (87.3 kg/ha-cm) and soil profile moisture was extracted with irrigation at 40 mm CPE. Application of sulfosulfuron recorded significantly lowest weed biomass and the highest nutrient content and their uptake, grain and straw yield, and maximum consumptive use of water (51.5 cm), rate of water use (4.02 mm/day), water use efficiency (91.3 kg/ha-cm) and soil profile moisture extraction over metribuzin and it was at par with metsulfuron-methyl. Grain (6.57 kg/ha) and straw yield (12.3 kg/ha) will be reduced by an increased in unit dry matter production in weeds.

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Climate Sensitivity of Tropical Trees Along an Elevation Gradient in Rwanda

Forests ◽

10.3390/f9100647 ◽

2018 ◽

Vol 9 (10) ◽

pp. 647 ◽

Cited By ~ 1

Author(s):

Myriam Mujawamariya ◽

Aloysie Manishimwe ◽

Bonaventure Ntirugulirwa ◽

Etienne Zibera ◽

Daniel Ganszky ◽

...

Keyword(s):

Water Use Efficiency ◽

Water Use ◽

Climate Sensitivity ◽

Elevation Gradient ◽

High Elevation ◽

Dry Season ◽

Nutrient Ratios ◽

Wet Season ◽

Elevation Gradients ◽

Use Efficiency

Elevation gradients offer excellent opportunities to explore the climate sensitivity of vegetation. Here, we investigated elevation patterns of structural, chemical, and physiological traits in tropical tree species along a 1700–2700 m elevation gradient in Rwanda, central Africa. Two early-successional (Polyscias fulva, Macaranga kilimandscharica) and two late-successional (Syzygium guineense, Carapa grandiflora) species that are abundant in the area and present along the entire gradient were investigated. We found that elevation patterns in leaf stomatal conductance (gs), transpiration (E), net photosynthesis (An), and water-use efficiency were highly season-dependent. In the wet season, there was no clear variation in gs or An with elevation, while E was lower at cooler high-elevation sites. In the dry season, gs, An, and E were all lower at drier low elevation sites. The leaf-to-air temperature difference was smallest in P. fulva, which also had the highest gs and E. Water-use efficiency (An/E) increased with elevation in the wet season, but not in the dry season. Leaf nutrient ratios indicated that trees at all sites are mostly P limited and the N:P ratio did not decrease with increasing elevation. Our finding of strongly decreased gas exchange at lower sites in the dry season suggests that both transpiration and primary production would decline in a climate with more pronounced dry periods. Furthermore, we showed that N limitation does not increase with elevation in the forests studied, as otherwise most commonly reported for tropical montane forests.

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Assessment of drip and flood irrigation on biomass production, nutrient content and water use efficiency of maize (Zea mays L.)

Dhaka University Journal of Biological Sciences ◽

10.3329/dujbs.v22i1.46273 ◽

2013 ◽

Vol 22 (1) ◽

pp. 47-54

Author(s):

AHMZ Ali ◽

SU Ahmed ◽

MM Rahman ◽

MK Rahman

Keyword(s):

Water Use Efficiency ◽

Water Use ◽

Biomass Production ◽

Drip Irrigation ◽

Zea Mays L ◽

Nutrient Content ◽

Flood Irrigation ◽

Use Efficiency ◽

Irrigation Treatments ◽

Surface Drip Irrigation

An experiment was conducted in wooden boxes to assess flood, surface and sub-surface drip irrigation on biomass production, nutrient content and water use efficiency of maize (Zea mays L.). Four levels of irrigation treatments were applied: (i) SD1 = Drip irrigation pipe was set up on the surface of the soil ; (ii) SSD2 = Drip irrigation pipe was buried up to 5 cm depth; (iii) SSD3 = Drip irrigation pipe was buried up to 7.5 cm depth and (iv) FI = Flood irrigation was practiced without any drip irrigation pipe. Leaf area, leaf area index and biomass production of maize were significantly (p < 0.05) higher in SSD3 than SSD2 and FI treatments. Biomass production was 37.2, 41.1, 54.2 and 35.2 g in SD1, SSD2, SSD3 and FI treatments, respectively. Water use efficiency (WUE) was also significantly (p < 0.05) higher in surface and sub-surface drip irrigation than flood irrigation. Values for WUEs were 0.248, 0.298, 0.430 and 0.156 kg/m3 in SD1, SSD2, SSD3 and FI treatments, respectively. As a result, all three drip irrigation treatments enhanced water use efficiencies than flood irrigation. Comparing the three drip irrigation treatments, significantly (p < 0.05) higher nitrogen was found both in leaf and stem (3.3 and 3.8%) in sub-surface drip irrigation at 7.5 cm depth than flood irrigation (2.2 and 1.4%). Although, potassium contents in leaf and stem were not significantly different between the treatments, but had a tendency to be higher in drip irrigation treatments. Above all, drip irrigation performed better with higher water use efficiency. Dhaka Univ. J. Biol. Sci. 22(1): 47-54, 2013 (January)

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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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