Optimizing row spacing increased radiation use efficiency and yield of maize

SUMMARYA field experiment was conducted at Gandhi Krishi Vignana Kendra, University of Agricultural Sciences, Bangalore to study the effect of irrigation regimens on the biomass accumulation, canopy development, light interception and radiation use efficiency of sunflower. The treatments includes irrigating the plants at 0.4, 0.6, 0.8 and 1.0 cumulative pan evaporation. The results indicated that the aboveground biomass, canopy development, radiation interception and radiation use efficiency were influenced favorably by the irrigation regimens. Irrespective of the irrigation regimen, the radiation use efficiency of sunflower increased from 15 DAS to 75 DAS and then tended to decline. The decrease in RUE after anthesis is coupled with decrease in leaf nitrogen content. In general the RUE of sunflower ranged from 0.49 g MJ-1 to 1.84 g MJ-1 at different growth stages. The light transmission within the canopy increased exponentially with plant height and the canopy extension coefficient is found to be 0.8.

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Intercepted Photosynthetically Active Radiation (PAR) and Spatial and Temporal Distribution of Transmitted PAR under High-Density and Super High-Density Olive Orchards

Agriculture ◽

10.3390/agriculture11040351 ◽

2021 ◽

Vol 11 (4) ◽

pp. 351

Author(s):

Adolfo Rosati ◽

Damiano Marchionni ◽

Dario Mantovani ◽

Luigi Ponti ◽

Franco Famiani

Keyword(s):

Spatial Variability ◽

Photosynthetically Active Radiation ◽

Temporal Distribution ◽

High Density ◽

Radiation Use Efficiency ◽

Spatial And Temporal Distribution ◽

Active Radiation ◽

Use Efficiency ◽

And Performance ◽

Radiation Use

We quantified the photosynthetically active radiation (PAR) interception in a high-density (HD) and a super high-density (SHD) or hedgerow olive system, by measuring the PAR transmitted under the canopy along transects at increasing distance from the tree rows. Transmitted PAR was measured every minute, then cumulated over the day and the season. The frequencies of the different PAR levels occurring during the day were calculated. SHD intercepted significantly but slightly less overall PAR than HD (0.57 ± 0.002 vs. 0.62 ± 0.03 of the PAR incident above the canopy) but had a much greater spatial variability of transmitted PAR (0.21 under the tree row, up to 0.59 in the alley center), compared to HD (range: 0.34–0.43). This corresponded to greater variability in the frequencies of daily PAR values, with the more shaded positions receiving greater frequencies of low PAR values. The much lower PAR level under the tree row in SHD, compared to any position in HD, implies greater self-shading in lower-canopy layers, despite similar overall interception. Therefore, knowing overall PAR interception does not allow an understanding of differences in PAR distribution on the ground and within the canopy and their possible effects on canopy radiation use efficiency (RUE) and performance, between different architectural systems.

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Relationships among light distribution, radiation use efficiency and land equivalent ratio in maize-soybean strip intercropping

Field Crops Research ◽

10.1016/j.fcr.2018.05.010 ◽

2018 ◽

Vol 224 ◽

pp. 91-101 ◽

Cited By ~ 36

Author(s):

Xin Liu ◽

Tanzeelur Rahman ◽

Chun Song ◽

Feng Yang ◽

Benying Su ◽

...

Keyword(s):

Light Distribution ◽

Radiation Use Efficiency ◽

Land Equivalent Ratio ◽

Equivalent Ratio ◽

Use Efficiency ◽

Strip Intercropping ◽

Radiation Use

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SEED-ORIENTED PLANTING IMPROVES LIGHT INTERCEPTION, RADIATION USE EFFICIENCY AND GRAIN YIELD OF MAIZE (Zea mays L.)

Experimental Agriculture ◽

10.1017/s0014479716000326 ◽

2016 ◽

Vol 53 (2) ◽

pp. 210-225 ◽

Cited By ~ 5

Author(s):

GUILHERME M. TORRES ◽

ADRIAN KOLLER ◽

RANDY TAYLOR ◽

WILLIAM R. RAUN

Keyword(s):

Grain Yield ◽

Canopy Structure ◽

Maize Yield ◽

Light Interception ◽

Plant Population ◽

Radiation Use Efficiency ◽

Seed Placement ◽

Use Efficiency ◽

The Difference ◽

Radiation Use

SUMMARYSeed-oriented planting provides a manner to influence canopy structure. The purpose of this research was to improve maize light interception using seed-oriented planting to manipulate leaf azimuth across the row thereby minimizing leaf overlap. To achieve leaf azimuths oriented preferentially across the row, seeds were planted: (i) upright with caryopsis pointed down, parallel to the row (upright); and (ii) laying flat, embryo up, perpendicular to the row (flat). These treatments were compared to conventionally planted seeds with resulting random leaf azimuth distribution. Seed orientation effects were contrasted with three levels of plant population and two levels of hybrid specific canopy structures. Increased plant population resulted in greater light interception but yield tended to decrease as plant population increased. The planophile hybrid produced consistently greater yields than the erectophile hybrid. The difference between planophile and erectophile hybrids ranged from 283 to 903 kg ha−1. Overall, mean grain yield for upright and flat seed placement increased by 351 and 463 kg ha−1 compared to random seed placement. Greater cumulative intercepted photosynthetically active radiation (CIPAR) was found for oriented seeds rather than random-oriented seeds. At physiological maturity upright, flat and random-oriented seeds intercepted 555, 525 and 521 MJ m−2 of PAR, respectively. Maize yield responded positively to improved light interception and better radiation use efficiency. Under irrigated conditions, precision planting of maize increased yield by 9 to 14% compared to random-oriented seeds.

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