Our objectives were (i) to monitor changes leaf ahsorptance in a typical maize crop over the growing season, and (ii) to determine if absorptance of maize leaves could be accurately estimated with a SPAD 502 hand‐held chlorophyll meter (Minolta Corporation, Ramsey, NJ). Leaf reflectance in the 0.40‐ to 0.75‐μm wavelength interval is influenced primarily by the pigments chlorophyll and carotenoid. In its liquid state, water has relatively low reflectance, with clear water having the greatest reflectance in the blue portion of the visible part of the spectrum. Winter Cover Crops in Illinois: Evaluation of Ecophysiological Characteristics of Corn. However, the literature contains very few references to the relation between reflectance from leaves and their carotenoid content. The Response of Leaf Photosynthesis and Dry Matter Accumulation to Nitrogen Supply in an Older and a Newer Maize Hybrid LEAF REFLECTANCE & VEGETATION INDICES. Green vegetation leaf reflectance primarily depends on several leaf parameters, such as the internal structural parameters of the leaf mesophyll, pigment content (e.g., Chl, carotenoid, and anthocyanin), leaf water content, and leaf dry matter content [13,14,15]. Leaf reflectance depends primarily on: a) The pigments b) Internal cell structure c) Equivalent water content d) All of these Leaf reflectance depends primarily on_____? Vegetation typically absorbs in the red and blue wavelengths, reflects in the green wavelength, strongly reflects in the near infrared (NIR) wavelength, and displays strong absorption features in wavelengths where atmospheric water is present. Genetic Variation in Physiological Discriminators for Cold Tolerance—Early Autotrophic Phase of Maize Development, https://doi.org/10.2135/cropsci1997.0011183X003700020022x. and you may need to create a new Wiley Online Library account. Water has high absorption and virtually no reflectance in near infrared wavelengths range and beyond. Recent evidence suggests that chlorophyll fluorescence techniques can be used to determine photosynthetic rates of maize (Zea mays L.) leaves much more rapidly than is possible with conventional gas exchange methods. However, the accuracy of such measurements depends directly on the accuracy with which leaf absorptance of incident photons in the PAR (photosynthetically active radiation) region can be estimated. Effect of Drought Stress on Leaf and Whole Canopy Radiation Use Efficiency and Yield of Maize. The pigments B. Physiological Limitations to Photosynthetic Carbon Assimilation in Cotton under Water Stress. Greening of young leaves was associated with decreases in both reflectance and transmittance in the middle wavelengths of the PAR region, while leaf senescence was associated with increases in both reflectance and transmittance, primarily in the longer wavelengths of the PAR region. Counc. MATERIALS ANDMETHODS The term "light" will be used in this paper to indicate electromagnetic radiation regardless of whether this radiation is ultraviolet, visible, orinfrared. Elements of Remote Sensing Elements of Remote Sensing. Spectral reflectance of Vegetation •In the range from about 0.7 to 1.3 μma plant leaf typically reflects 40 - 50% of the energy incident upon it primarily due to the internal structure of plant leaves •Because the internal structure of leaves are highly variable between plant species, reflectance measurements in this range often permit us to Regression analysis revealed a strong relationship (r2 = 0.98) between leaf absorptance and SPAD value, suggesting that the SPAD meter could be used to provide a rapid estimate of leaf absorptance in the field. Internal cell structur C. Equivalent water content D. All of these. . A. If you do not receive an email within 10 minutes, your email address may not be registered, Turbid water has a higher reflectance in the visible regio… Greening of young leaves was associated with decreases in both reflectance and transmittance in the middle wavelengths of the PAR region, while leaf senescence was associated with increases in both reflectance and transmittance, primarily in the longer wavelengths of the PAR region. the reflectance curves depend on leaf composition and orien-tation. Leaves from six leaf positions were harvested on eleven dates between 55 and 134 d after planting. Learn more. Financial support provided, in part, by the Ontario Ministry of Agric., Food and Rural Affairs, and the Natural Sciences and Engineering Res. Maize Morphophysiological Responses to Intense Crowding and Low Nitrogen Availability: An Analysis and Review. 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