We present our results concerning a systematical analysis of helioseismic implications on solar structure and neutrino production .
We find Y _ { ph } = 0.238 - 0.259 , R _ { b } / R _ { \odot } = 0.708 - 0.714 and \rho _ { b } = ( 0.185 - 0.199 ) gr/cm ^ { 3 } .
In the interval 0.2 < R / R _ { \odot } < 0.65 , the quantity U = P / \rho is determined with and accuracy of \pm 5 ^ { \circ } / _ { \circ \circ } or better .
At the solar center still one has remarkable accuracy , \Delta U / U < 4 \% .
We compare the predictions of recent solar models ( standard and non-standard ) with the helioseismic results .
By constructing helioseismically constrained solar models , the central solar temperature is found to be T = 1.58 \times 10 ^ { 7 } K with a conservatively estimated accuracy of 1.4 % , so that the major unceratainty on neutrino fluxes is due to nuclear cross section and not to solar inputs .