Table 3 Genetic coefficients of maize cultivars

P1

The span of time (measured in ^◦C days, above a base temperature of 8^◦C) between the emergence of seedlings and the conclusion of the juvenile phase, during which the plant is not susceptible to variations in photoperiod

245

253

260

250

320

P2

The amount that development (measured in days) is postponed for every hour that the photoperiod is extended over the longest photoperiod (which is thought to be 12.5 h)

0.60

0.7

0.8

1.42

0.52

P5

Thermal period (measured in ^◦C days above a base temperature of 8 ^◦C) from silking to physiological maturity

850

945

950

942

962

G2

Maximum possible number of kernels per plant

780

490

440

484

470

G3

Kernel filling rate during the linear grain filling stage under optimum conditions (mg day⁻¹)

8.5

12.7

14.8

14.6

10.0

PHINT

Phyllochron interval, the interval in thermal time between successive leaf tip appearances (˚C day)

48

49

54.4

48.4

74.91