Disease:Wilt

Fusarium spp

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Symptoms

  • The pathogen affects the crop at any stage of crop growth.
  • Three different types of symptoms are commonly noticed in Amaranthus grown in Kerala.
  • Wilt: The plants show yellowing withering and drooping of leaves. The vines show blackening and drying. The roots show rotting and blackening.
  • Basal swelling: The affected Amaranthus plants became stunted and weak .The base of the stem swells up to the size of a small cassava tuber. The taproot and lateral roots are affected. The basal swollen portion becomes disintegrated and shredded.
  • The stem, leaf petioles become flattened. The flowers show fasciation and sterility.

Epidemiology

The pathogen is seedborne and soilborne. High temperature and high moisture or relative humidity is congenial for disease development.

Procedure for Observation

Assess the number of plants affected by observing 25 pits at random.

ETL

  • Mere presence

    • Control Measures

  • Ten days before sowing apply Trichoderma enriched with cow dung and neem cake in the pit.
  • Treat the seeds with Pseudomonas 1% solution. Drench the pit and spray the plant with Pseudomnas 2% when the plant attains 15 and 25 days. This treatment can be repeated based on need.
  • Drenching the base and spraying the plant with copper oxy chloride (@0.4%).
  • There should be a gap of ten days between coc and Pseudomonas application.