TITLE:
Grain Yield Differences of Soybean Cultivars Due to Solar Radiation Interception
AUTHORS:
Mariele Müller, Miroslava Rakocevic, Andréia Caverzan, Geraldo Chavarria
KEYWORDS:
Glycine Max, Leaf Area Index, Efficiency of Solar Radiation Interception, Extinction Coefficient, Solar Radiation Use Efficiency
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.8 No.11,
October
26,
2017
ABSTRACT: Soybean
[Glycine max (L.) Merr.] growth rate and
grain yield are modified by the interception and solar radiation use efficiency.
Thus, it is desirable that the most of plant photosynthetic structures intercepting
solar radiation in order to have increment in carbon fixation and reflection on growth and
yield. The goal of this study was to assess if soybean cultivars differ in grain
yield in relation to solar radiation interception. Four soybean
cultivars were evaluated at stages V6, V9, R2, R4, R6 and R8. To determine the photosynthetically
active radiation interception by the canopy, the plants
were divided into two parts (upper and lower strata). For grain
yield components, the plants were divided into three parts (upper, middle and lower
thirds). Of the photosynthetically active radiation intercepted by the vegetative
canopy at the reproductive stages, the maximum observed intercept was 5.2% in the
lower stratum of the plants. The number of infertile nodes increased in the lower
third of plants due to low interception of solar radiation in this plant region.
Thus, the soybean cultivars more efficient in intercepting photosynthetically active
radiation inside the vegetative canopy showed higher grain yields.