What are the reasons rice seedlings are slow to tiller

1. Rice bakanae disease:

Patterns of occurrence and routes of transmission: The pathogen of rice bakanae disease overwinters on grains and rice straw. The following year, if infected seeds or rice straw are used, the pathogen multiplies as the seeds germinate, invading through the coleoptile or wounds of the seedlings, causing the seedlings to develop the disease and grow excessively tall. Affected seedlings often wither and die. Infected seedlings that do not die are pale yellow-green, grow thin and elongated, generally about one-third taller than healthy seedlings; root development is poor, with few tillers or even no tillering. After infected seedlings are transplanted, they carry the pathogen into the field, causing rice plants to develop the disease. When rice heads and flowers, the pathogen is spread by wind and rain to the floral organs, causing grains and rice straw to carry the pathogen, cyclically infecting and damaging rice. The pathogen easily invades through wounds, so sowing mechanically damaged rice seeds, or seedlings with severe root injury, results in more severe disease. Dry-raised seedlings often develop more severe disease than water-raised seedlings.

Control methods: The focus of controlling rice bakanae disease is on seed treatment.

(1) Select disease-free seeds for seed preservation. This is a relatively reliable and most effective method.

(2) Strictly disinfect seeds. Soak seeds with strong chlorine essence; or use 100 g of 50% carbendazim, add 50 kg of water to soak seeds; or use 120 g of 35% bakanae fungicide, add 50 kg of water to soak seeds; or soak seeds in 3% quicklime water for 48 hours. When soaking seeds in the solution, it must be noted that the liquid level must be 15 cm-20 cm above the seed layer, for the seeds to absorb. At the same time, during the soaking process, the liquid surface must remain still; it must not be stirred midway, nor reused, to ensure the pathogen is suffocated.

(3) Whether in the seedling field or the main field, diseased plants should be pulled out promptly to prevent further infection.

(4) Properly handle diseased rice straw; it must not be thrown away casually, nor piled at the field edges or corners, nor used as a covering for seed sprouting, nor used to tie seedling bundles. It can be centrally composted at high temperature, and in severe cases burned.