Effect of canopy structure on efficiency of radiation interception and use in spring wheat cultivars during the pre-anthesis period in a mediterranean-type environment

Yunusa, Isa; Siddique, Kadambot H. M.; Belford, R. K.; Karimi, M.

doi:10.1016/0378-4290(93)90144-c

Cited by 68 publications

(43 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…These findings are in line with those Gregory et al (1992); Yunusa et al (1993);Latiri-Souki et al (1998). They found that for wheat in semi-arid conditions and at different irrigation and nitrogen levels, the conversion efficiency of the incident PAR varies between 0.9 g MJ -1 for treatments without irrigation and without nitrogen and 1.5 g MJ -1 for treatments with irrigation and nitrogen.…”

Section: Discussionsupporting

confidence: 82%

Deficit Irrigation of Durum Wheat (Triticum durum Desf): Effects on Total Dry Matter Production, Light Interception and Radiation Use Efficiency Under Different Nitrogen Rates

M’hamed¹,

Rezig²,

Naceur³

2014

SAR

View full text Add to dashboard Cite

On-farm trial was conducted from 2005 to 2008 to test the hypothesis that reduction of total dry matter (TDM) in crops can occur after a decreased radiation use efficiency (RUE) due to shortage of nitrogen and irrigation, we applied three irrigations treatments (D1, D2 and D3) and four nitrogen rates (N1, N2, N3 and N4). Photosynthetic active radiation absorbed or cumulative light interception (PARabs) and RUE of Durum wheat were measured. Results showed that D1N1 treatment recorded the highest LAI, PARabs, TDM and RUE. The maximum LAI was obtained 140 DAS (days after sowing) under treatment D1N2 (6.42) and the lowest LAI at the same phase belonged to treatment D2N4 (3.86). At the harvest, the maximum of TDM was 1487 g m -2 recorded under treatment D1N1. The minimum value obtained was 930 g m -2 under treatment D3N4. Also, PARabs was improved under D1N1 and D1N2 treatments. With reduced N application rates and irrigation doses, PARabs was decreased and the lowest values were observed under D3N4 condition. The RUE, varied from 1.55 g MJ -1 (D1N1) to 1.24 g MJ -1 (D3N4), was affected and decreased under deficit irrigation and low nitrogen conditions. In conclusion, the results of this study seem to show that D1N1 and D1N2 treatments can be beneficial for Durum wheat under field conditions in semi arid zone of Tunisia, for the purpose of improving RUE and maximizing grain yield.

show abstract

Section: Discussionsupporting

confidence: 82%

Deficit Irrigation of Durum Wheat (Triticum durum Desf): Effects on Total Dry Matter Production, Light Interception and Radiation Use Efficiency Under Different Nitrogen Rates

M’hamed¹,

Rezig²,

Naceur³

2014

SAR

View full text Add to dashboard Cite

show abstract

“…Measurements were made between 1100 and 1300 hours mostly at fortnightly intervals, and 180 used along with measurements of incident radiation to determine radiation use efficiency 181 (RUE) following the procedures described by Yunusa et al (1993b). Briefly, fraction of 182 PAR intercepted by the canopy was obtained as: i PAR = 1 -(Ρ a / Ρ b ), and was used to scale 183 sums of incident solar radiation measured at a nearby whether station between sampling 184 intervals to obtain amount of PAR intercepted by the crops (MJ m The dry season in 1994 severely inhibited growth and yields for crops both in sole and 258 mixed plots (Table 1).…”

mentioning

confidence: 99%

Radiation- and water-use associated with growth and yields of wheat and chickpea in sole and mixed crops

Jahansooz

Yunusa

Coventry

et al. 2007

European Journal of Agronomy

Self Cite

View full text Add to dashboard Cite

17There is a renewed interest in boosting farm productivity in the semi-arid Mediterranean 18 agricultural zones of Australia through increased capture and use of solar radiation and soil-19 water by simultaneous growing of two or more species of plants in mixtures. The present 20 study assessed the performance of wheat and chickpea, mixed at half their sole crop 21 populations for their capacity to capture and use solar radiation and soil-water in the 22 drought season of 1994 and close-to-normal rainfall season of 1995 in South Australia. In 23 both years, there was no advantage of mixed crops over wheat grown as a sole crop (wheat-24 s) either in terms of green area index (GAI), fraction of photosynthetically active radiation 25 intercepted by the canopy (i PAR ), dry matter (DM) or grain yield produced. The lack of a 26 yield advantage of mixed cropping was associated with the low yielding capacity of 27 chickpea and its inability to compensate for its reduced population density in the mixture. 28Grain yield for chickpea in the mixed crop (chickpea-m) averaged just 29% that of its sole 29 crop (chickpea-s), whereas wheat grown in mixture (wheat-m) produced 72% the yield for 30 wheat-s. Supplementary irrigation from early spring onwards in 1995 increased yield of 31 chickpea-m by 44% over that of chickpea-s, while wheat-m fell to 65% that of wheat-s. 32Every millimetre of irrigation water increased yield by 10.0, 3.8 and 12.5 kg/ha for wheat-s, 33 mixed crop and chickpea-s, respectively. Mixed cropping did not affect the time taken by 34 either wheat or chickpea to attain maximum growth rate, flowering or maturity. Using the 35 land equivalent ratio (LER) to assess productivity in terms of grain yields for wheat-36 chickpea intercropping produced values of between 1.01 in 1994 and 1.02 in 1995; an LER 37 of 1.10 was obtained with supplementary irrigation in 1995. Mixed cropping did not 38 improve either radiation-use efficiency or water-use efficiency when compared to wheat-s. 39It is concluded that there was no advantage of mixed cropping when based on total biomass 40 or grain yield produced by the crops. 41 42 43

show abstract

“…Nevertheless, a common aspect of these studies is that they relied on theoretical calculations. As pointed out by Yunusa et al (1993), and later by Sattin et al (1997), there is a lack of experimental, field-obtained data on this subject.…”

Section: Introductionmentioning

confidence: 99%

“…Therefore, it is possible to argue that instantaneous, around-noon measurements of radiation transmittance, as is rather commonly reported in crop light capture-or RUE-related studies (e.g. Gallo et al, 1993;Yunusa et al, 1993;Lizaso et al, 2003) may not be a good practice when these studies are done on discontinuous canopies such as fruit trees or horticultural crops in their early stages of development, confirming the theoretical results of Sinclair (2006). In fact, τPAR and τSg measurements performed around noon tended to be higher than the daily weighted average, potentially introducing errors if the former are taken as representative of the overall daily situation.…”

Section: Radiation Transmittance Relationsmentioning

confidence: 99%

In Field Assessment on the Relationship between Photosynthetic Active Radiation (PAR) and Global Solar Radiation Transmittance through Discontinuous Canopies

Oyarzún

Stöckle

et al. 2011

Chilean J. Agric. Res.

View full text Add to dashboard Cite

In many crop models, the process of radiation transmittance through the canopy is normally described as an exponential attenuation process (Beer's Law equation), which is assumed to be valid for canopies covering the ground with a random spatial distribution of leaves. However, for discontinuous canopies, where a distinctive row pattern of plant exists, there is a more complex situation because of the presence of gaps between individual plants. This must be accounted for when characterizing radiation relationships for these kinds of systems, in particular when short time-scales are of interest. Photosynthetically active radiation (PAR) transmittance (τPAR) is more commonly studied and reported than global solar radiation (Sg) transmittance (τSg). However, both PAR and Sg are important in radiative transfer sub-models used in plant growth simulation. In this work simultaneous measurements of τSg and τPAR under discontinuous canopies were performed, and the hourly changes in radiation transmittance for PAR and global solar radiation were characterized. Two methods were assessed to transform between τSg and τPAR. The two methods yielded similar results for low values of transmittance, but disagreement occurred for higher values of transmittance. The method based on a fixed value for the ratio of extinction coefficients for PAR and Sg outperformed the method based on a linear relationship between τPAR and τSg with average relative errors (RE) of 7.97% vs. 13.29% and 2.84% vs. 7.77% for hourly and daily time-scale, respectively.

show abstract

Effect of canopy structure on efficiency of radiation interception and use in spring wheat cultivars during the pre-anthesis period in a mediterranean-type environment

Cited by 68 publications

References 16 publications

Deficit Irrigation of Durum Wheat (Triticum durum Desf): Effects on Total Dry Matter Production, Light Interception and Radiation Use Efficiency Under Different Nitrogen Rates

Deficit Irrigation of Durum Wheat (Triticum durum Desf): Effects on Total Dry Matter Production, Light Interception and Radiation Use Efficiency Under Different Nitrogen Rates

Radiation- and water-use associated with growth and yields of wheat and chickpea in sole and mixed crops

In Field Assessment on the Relationship between Photosynthetic Active Radiation (PAR) and Global Solar Radiation Transmittance through Discontinuous Canopies

Contact Info

Product

Resources

About