Causes of citrus decline and its management practices adopted in Myagdi district, Nepal

Heliyon. 2022 Jul 9;8(7):e09906. doi: 10.1016/j.heliyon.2022.e09906. eCollection 2022 Jul.

Abstract

Citrus decline has been the major constraint faced by citrus growers in Nepal. Survey research was conducted in Beni municipality and Malika rural municipality of Myagdi district to study the cause of citrus decline and their management practices. A total of 94 mandarin growing farmers were selected randomly and interviewed with a semi-structured questionnaire. Analytical tools like logistic regression, multiple linear regression, and t-test were used to derive the inferences needed. The study showed that 72.3% of the mandarin growing farmers had experienced citrus decline problems in their orchards. Disease and pest incidence, climatic extremities, poor fertility status of soil, low-quality planting materials, and poor orchard management were found to be positively influencing citrus decline. Insect infestation was 52 percent more likely to cause citrus decline as compared to insect non-infested conditions. The study revealed that 75.5% of the farmers use farmyard manure (FYM) of more than 30 kg per plant per year, 44.7% of the farmers use chemical fertilizers, 85.1% of the farmers irrigate their orchard, 98.94% of farmers practice weeding, 33% of the farmers practice mulching, 84% of the farmers practice pruning, 50% of the farmers use Bordeaux mixture and 61.7% of the farmers manage insects. Moreover, effective orchard management practices like manuring, irrigation, pruning, Bordeaux application, and insect management were significantly associated with a higher percentage of rejuvenation of declining orchards. The productivity of mandarin orchards, in addition, was significantly enhanced by FYM application, chemical fertilizers, irrigation, weeding, and Bordeaux application. This study elucidated that citrus decline has been the major constraint of mandarin farming, and improved management practices are pivotal for combating the citrus decline.

Keywords: Citrus decline; Management practices; Orchard; Productivity; Rejuvenation.