Analysis of Reference Evapotranspiration (ETo) and Rainfall on Maize Hybrid Seed Production: Cases in Malang and Jember

Maize hybrid seed production cultivation area often has less pollen available than in regular commercial maize because of detasseling to eliminate self-pollination. There are also concerns regarding the increasing intensity of extreme weather following climate change, on top of inherent maize sensitivity to water stress in the flowering period. The objective of this study was to determine the relationship between rainfall, reference evapotranspiration (ETo), and maize hybrid seed yield in two locations using simple regression analysis. Four years of historical weather and harvest data of one type of parental maize line were obtained from Talangsuko, Malang Regency, and Sukoreno, Jember Regency. In conclusion, there was a strong linear and negative relationship between rainfall and the yield of hybrid maize seeds in Talangsuko (R2=0.60), while in Sukoreno, the relationship was in the form of a quadratic curve (R2=0.61). In Talangsuko, there was a strong relationship between rainfall in the flowering period and maize yields (R2=0.60), meanwhile, in Sukoreno, only a few samples experienced rain during the flowering period and consecutive rain so the relationship with maize yields could not be concluded (R2=0.09 and 0.18). There was no relationship between ETo FAO-56 PM and hybrid maize seed yield (R2=0.04 and 0.06).