How to treat sugarcane pokkah boeng? Latest prevention and control techniques and methods tutorial
Sugarcane pokkah boeng is a fungal disease in which the base of infected young leaves becomes chlorotic and yellowed, narrower than normal leaves, with the leaf blade notably wrinkled, twisted, or shortened. The pathogen's conidia spread through the air and land on the spindle leaf at the top of the stalk, where they germinate and invade the base of the young tender leaves. The diseased area then produces conidia, causing repeated infection. Let us take a look below at the prevention and control techniques for sugarcane pokkah boeng!
Symptoms of sugarcane pokkah boeng damage
In sugarcane plants with pokkah boeng, the base of infected young leaves becomes chlorotic and yellowed, narrower than normal leaves, and the leaf blade is notably wrinkled, twisted, or shortened. After the diseased leaves age, irregular red spots or red streaks appear on the diseased area; some reddened tissue forms irregular eye-shaped or diamond-shaped perforations, and some forms dark brown lesions arranged in a ladder-like pattern along the edges. Dark reddish-brown to black irregular lesions also form on the leaf margins and leaf tips, and some leaves have their expansion blocked, showing a knotted appearance at the tip. Infected leaf sheaths bear red necrotic spots or ladder-like lesions. When the spindle at the top of the stalk is infected, a longitudinal cut reveals many deep red streak marks, with the streak marks at the nodes appearing as thin lines, and some internodes form long sunken lesions with transverse septa, resembling a ladder. When the diseased area occurs on one side of the stalk, it causes the cane stalk to bend. In the most severe cases, pokkah boeng forms, the tissue around the growing point softens and turns brown, and the spindle leaf becomes necrotic, causing the entire sugarcane plant to die.
Conditions for the onset of sugarcane pokkah boeng
The pathogen on diseased plants and on plant residues decaying on the soil surface spreads and progresses with air currents. The conidia land on the spindle leaf at the top of the stalk and, under suitable conditions, germinate and invade the young tender leaves of sugarcane. The diseased area produces conidia for reinfection. Sugarcane fields with high temperature and high humidity, or with a long drought followed by rain, or with excessive irrigation, are prone to the disease. Insufficient nitrogen fertilizer, weak and thin plant growth, or excessive or over-application of nitrogen fertilizer, which makes plant tissues tender and causes overly rapid growth, results in severe disease. Yuetang 54/176, Yuetang 57/423, and Shuntang 66/166 are relatively susceptible.
Prevention and control techniques for sugarcane pokkah boeng
1. Select resistant varieties such as Guitang 57/624 and Yuetang 63/237.
1. Advocate the application of compost fermented with EM (effective microorganisms) or fully decomposed organic fertilizer, adopt formula fertilization techniques, pay attention to the reasonable combined application of nitrogen, phosphorus, and potassium, and avoid one-sided or excessive application of nitrogen fertilizer.
3. Repair and maintain the drainage and irrigation system well, and drain standing water promptly.
4. Strengthen management, promptly strip off old leaves, remove ineffective tillers, and dig out and remove diseased plants.
5. In severely affected areas, at the early stage of disease, spray 1:1:100 Bordeaux mixture or 30% Ludebao suspension concentrate at 500 times dilution, or 50% benomyl wettable powder at 1000-1200 times dilution, once every 7-10 days, for 3-4 consecutive treatments.