The Rubber Board has ruled out any cause for alarm over incidents of powdery mildew and corynespora, both leaf-fall diseases, this season as favourable conditions have helped rubber plants nearly escape the yearly cycle of mildew attacks.
Responding to reports that farmers in the upper reaches of Kothamangalam such as Neryamangalam and Adimali were seeing serious incidence of leaf-fall with extreme temperature differences between early morning hours and day time, board sources say the December-February period is re-foliage period when new leaves are generated.
The traditional rubber areas such as Travancore, Malabar, and areas around Kothamangalam are witness to attacks of powdery mildew as well as corynespora during the season. However, powdery mildew has almost been out of the picture this season because of the heavy rains in the latter part of the year. Powdery mildew can cause yield reduction and corynespora disease in immature plantations cause delay in maturing of the rubber trees.
Instances of corynespora have been detected in northern Kerala, which include southern Karnataka, some parts of Kasaragod district as well as Taliparamba and Sreekandapuram. The Rubber Board has been proactive, providing free materials for spraying to contain the leaf-fall disease in these areas, the sources said.
In the meanwhile, the board is providing support to farmers across the rubber-growing areas in Kerala, Kanyakumari and southern Karnataka to control colletotrichum circular leaf spot (CCLS), which has been detected during the rainy season starting about the month of May.
The disease was detected in Kerala and some parts of Tamil Nadu in 2017 and was found to be prevalent between April-May and November. The cause of the disease has been identified by the Rubber Research Centre as colletotrichum fungus. The findings pointed out that the disease was similar to the leaf-fall disease found in Indonesia, Sri Lanka, Malaysia, and Thailand.
The disease was initially found at a rubber plantation at Paika, in Kottayam, in July 2017. A survey was conducted in July 2018 and it was found that the disease was prevalent at Paika, Palai, Erattupetta, Chengalam, Chettuthodu, as well as in Pathanamthitta, Thrissur, Punalur, and Thodupuzha. The disease was detected in 2020 in traditional rubber areas in Kanyakumari too.
The sources said there was no reason to be alarmed about the situation. The board has a clinic that addresses any disease situation on a real-time basis. Farmers can WhatsApp their problems along with pictures of the diseased trees or leaves to 9496333117.
