Light intercepted

When sowing crops, drilling in an east-west direction can provide better shadowing of interrow space and light interception by the crop. The occurrence of Apera spica-venti could be reduced more under erectophile cultivars drilled from east-west compared to north-south. The effect of planophile cultivars was similar in both drilling directions tested (Kbpke 2000). 

When light intercepts an obstacle it will be scattered, and measurement of the amplitude and polarization properties of the scattered light at various angles relative to the incident beam can provide important structural and dynamic information about a material. Figure 4.1 describes the basic light scattering experiment. Incident light with an electric field E-... 

Increase the distance between the rows of citrus trees from 6 to 9 metres, cutting down several rows of citrus trees. Lower-density plantings are better adapted to the organic production system they increase ventilation and light interception and thus decrease disease pressure. Lower tree density gives space for crops in the alleyway between rows. 

The acquisition of carbon is strongly modulated by the surface area of photosynthesizing leaves hence, understanding leaf area development is germane to efforts to increase yield. In many crops, biomass is linearly related to the amount of light intercepted (Monteith, 1977). This is certainly the case for Jerusalem artichoke, where total productivity is strongly correlated with the amount of solar radiation intercepted (Denoroy, 1996 Meijer et al., 1993). Leaf area, leaf duration, and photosynthetic efficiency of the crop canopy determine how much light is intercepted and subsequently utilized (Table 10.9). 

Canopy light extinction coefficient (k) Calculated using the function LI = 1 — exp( t LAI), where LI is the fraction of light intercepted by the canopy and LAI is leaf area index (m2 leafm-2 land) Varies3 ... 

In addition to light interception, the acquisition of minerals (e.g., nitrogen, phosphorous, and sulfur) from the environment is vital for photosynthetic processes to proceed efficiently. Chemical composition is one component of dynamic simulation modeling (Denoroy, 1996). 

Chen, S.G., Shao, B.Y., Impens, I., and Ceulemos, R., Effects of plant canopy structure on light interception and photosynthesis, J. Quant. Spectrosc. Rad. Trans., 52, 115-123, 1994. 

Enhanced "harvest index" Improved standing ability Improved light interception Improved shoot/root ratio... 

Isobutylmethoxypyrazine decreased consistently, but ethylmethoxypyrazine displayed a concentration that was somewhat erratic (Table II). A similar situation was found when the effect of light interception by the fiuit was examined. Higher light levels decreased the concentration of isobutylmethoxypyrazine but did not consistently influence ethylmethoxypyrazine. 

For particles much larger than the wavelength of the incident light (x 1), the scattering efficiency approaches 2. That is, a targe particle removes from the beam twice the amount of light intercepted by its geometric cross-sectional area. What is the explanation for this paradox ... 

Firman, D. M. Allen, E. J. (1989). Relationship between light interception, ground cover and leaf area index in potatoes. The Journal of Agricultural Science, Vol. 113, pp. 355-359, ISSN 0021-8596, EISSN1469-5146... 

This inhibition was attributed to the epinastic response of the plants and the associated reduction in total light interception. The... 

Fig. 7. Light interception by leaves at different positions in the canopy of WT and Psagi2 IFT tobacco plants. Each data point is the mean from 3 different plants of each genotype (A). Pmax for leaves of different ages within the canopy of three WT and three PsAcndPT tobacco plants (B). Photosynthetic light response of newly mature upper canopy leaves (2-3 weeks old) from three WT and three PsAcndPT tobacco plants (C).

The cover and composition of understory vegetation in all these cover types will vary depending onsite (climate and soil), associated tree species, stand developmental stage, and stand density. Relative to other tree species, light interception by western white pine is low, thus providing favourable light conditions for the development of diverse understory vegetation. 

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