The leaf rust disease development of hybrid corn on shaded agroecosystem

The research objective was to determine the development of hybrid corn leaf rust disease in shaded agro-ecosystems. The research was carried out in the albasia forest area of Kalices Village, Patehan District, Kendal Regency, Central Java, Indonesia in March-September 2020. Three hybrid corn varieties, namely JH 37, Nasa 29 and Bisi 18, were used as treatments, as well as three levels of shade density, namely 0, 20 and 40%. Observations were made on the incidence and intensity of leaf rust disease at the age of 40, 60 and 80 days after planting (DAP). The incidence and intensity of leaf rust disease were observed by scoring according to the modified 2012 DMRI method. The results showed that all three varieties had been attacked by leaf rust disease since 40 DAP with an incidence of 13.33–56.67% and disease intensity between 12.59–17.41% at all levels of shade density. The leaf rust disease continues to develop in all varieties with an intensity of around 30.00-56.67%. The highest incidence and intensity of leaf rust disease occurred in JH 37 variety at all levels of shade density. The development of leaf rust disease is more influenced by the genetic characteristics of each variety.