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We investigate effects of triple-$\alpha$ and $^{12}\rm C(\alpha,\gamma)^{16}O$ reaction rates on the production of supernova yields for a massive starof 25 $M_{\odot}$. We combine the reaction rates to examine the ratedependence, where the rates are considered to cover the possible variation ofthe rates based on experiments on the earth and theories. We adopt fourcombinations of the reaction rates from two triple-$\alpha$ reaction rates andtwo $^{12}\rm C(\alpha,\gamma)^{16}O$ ones. First, we examine the evolution ofmassive stars of 20 and 25 $M_{\odot}$ whose helium cores correspond to heliumstars of 6 and 8 $M_{\odot}$, respectively. While the 25 $M_{\odot}$ starsevolve to the presupernova stages for all combinations of the reaction rates,evolutionary paths of the 20 $M_{\odot}$ stars proceed significantly differentway for some combinations, which are unacceptable for progenitors ofsupernovae. Second, we perform calculations of supernova explosions within thelimitation of spherical symmetry and compare the calculated abundance ratioswith the solar system abundances. We can deduce some constraints to thereaction rates. As the results, a conventional rate is adequate for atriple-$\alpha$ reaction rate and a rather higher value of the reaction ratewithin the upper limit for the experimental uncertainties is favorable for a$^{12}\rm C(\alpha,\gamma)^{16}O$ rate.

Effects of Triple-$\alpha$ and $^{12}\rm C(\alpha,\gamma)^{16}O$ Reaction Rates on the Supernova Nucleosynthesis in a Massive Star of 25 $M_{\odot}$