Source: Times of India [summ., edited]
Continuous rainfall and poor sunshine have adversely affected a high quality variety of basmati rice sown across 16 000 hectares [39 537 acres] in Kasganj district. At least 25% of the crop has been affected by the fungal Bakanae disease in different parts of the district, according to farmers. The district agriculture department has sounded an alert. Farmers are being updated on methods to prevent crop loss, including use of a few permitted chemicals in severe cases. Teams are going to villages and farmers can also directly contact agriculture officers.
[Byline: Deepak Lavania]
[Bakanae disease of rice (also called foot rot) is reported from rice growing countries worldwide, except for Australia. It is caused by _Fusarium fujikuroi_ which is now considered a species complex that can also affect other crops, including maize (_Zea mays_; kernel rot), sorghum (_Sorghum_ spp.), and sugar cane (_Saccharum_ species and hybrids; pokkah boeng, see ProMED post 20200717.7582937).
Bakanae can cause significant crop losses of up to 50 percent in rice and is emerging as a major problem in Asia. Symptoms on rice may include abnormal growth patterns (such as highly elongated tillers), reduced tillering, partially filled or empty seed heads. Diseased plants show yellow-green discolouration; their leaves dry up quickly, they may be distributed irregularly in a field. Infected seedlings with necrotic lesions on roots may die before or after transplanting from seed beds.
Plants get infected through roots or crowns, the infection later becomes systemic. Seeds are usually infected during the flowering stage, the disease is primarily seed borne. The fungi survive under adverse conditions in infected seeds and diseased plant parts. Disease management is difficult and may include use of certified clean seeds, fungicides (such as seed treatments or root dips), phytosanitation, and use of crop cultivars with reduced pathogen sensitivity. Rapid development of new pathogen strains with fungicide resistances or able to break genetic host resistance has been observed.
Traditional rice cultivars previously grown across northern India have largely been replaced by basmati (aromatic long grain) varieties. Some basmatis have shown higher sensitivity to certain pathogens, for example to rice blast (_Pyricularia oryzae_; ProMED post 20160407.4145967).
A different foot rot disease of rice can be caused by several species of bacteria in the genus _Dickeya_ (see previous ProMED posts in the archives).
India (with states):
Uttar Pradesh districts:
Bakanae symptoms on rice:
http://www.knowledgebank.irri.org/smta/images/stories/Module2/Seed%20infected%20with%20Fusarium%20moniliforme.jpg (infected seed)
Information on bakanae disease:
https://link.springer.com/article/10.1007/s42360-018-0091-2 (review, with pictures)
_F. fujikuroi_ taxonomy and synonyms:
Basmati rice varieties in India: