Fusarium wilt of some shallot local varieties in Yogyakarta alternating-bed (surjan) agroecosystem

Abstract

Abstract Leaf twisted is one of the dominant diseases in shallot that is caused by Fusarium oxysporum f.sp. cepae. Rain intensity and air humidity due to climate change affect the severity of disease and become an essential factor for high yield loss. Alternating-bed system (surjan) is one land arrangement to cultivate multiple commodities in an irrigated rice agroecosystem. It is implemented by farmers in Yogyakarta. However, it relates to climate conditions. Research about tolerant or moderately resistant shallot varieties against leaf twisted disease in alternating-bed systems is very beneficial for farmers to increase yield. This research aims to determine the potential local shallot variety which is moderately resistant and tolerant against leaf twisted and provides high yield. The research was conducted at the alternating-bed system in Kulon Progo District, Yogyakarta Indonesia from August to September 2022. The experiment was designed in randomized blocks with five replications. Shallot varieties such as Siyem, Srikayang, Crok Kuning, and Tajuk were used in this experiment. Results showed that disease severity in Tajuk, Srikayang, Siyem, and Crok Kuning was 7.60%, 9.60%, 19.60%, and 14.00%, respectively. Disease incidence of Tajuk, Srikayang, Siyem, and Crok Kuning were 0.56%, 0.83%, 1.81%, and 1.25%, respectively. The yields of Tajuk, Srikayang, Siyem, and Crok Kuning were 7.34, 6.27, 5.31, and 7.04 tons per ha, respectively. Siyem and Crok Kuning were categorized as moderately resistant, while Srikayang and Tajuk were tolerant. All four varieties are potentially developed at alternating-bed systems in Yogyakarta.