It seems to be Foot Rot of Papaya which is caused by Pythium aphanidermatum.
It is a severe disease of papaya. It is characterized by the appearance of water-soaked patches on the stem near the ground level. These patches enlarge rapidly and girdle the stem, causing rotting of the tissues, which then turn dark brown or black. Such affected plants can't withstand strong wind and topple over and die. If the disease attack is mild, only one side of the stem rots and the plants remain stunted. Fruit if formed are shriveled and malformed. Gradually the plant dies.
Application of Trichoderma viride (15 g/plant) mixed in well-decomposed FYM should be applied around the root zone of the plants at the time of planting.
The crop should be irrigated by adopting the ring method of irrigation so that the water does not come in direct contact with the stem.
In the case of new plantings, preventing water logging of the soil may control the disease.
The soil should be drenched with 2-3 litres of Copper Oxychloride (3 g per litre of water). The application should be carried out regularly at 15 days interval from the time of planting. During fruit formation, the plant should be sprayed with the same solution at the same time interval.
Alternately, Mancozeb (2.5 g/ litre of water) may also be applied. In the case of disease attack in existing crops, the rotted portion of the plant should be scraped and Copper Oxychloride or Bordeaux paste should be applied.
Posted by: Rupinder Singh
Posted: March 15, 2017