The disease can be described based on the part of the plant infected as follow:i. Leaf Blast:
On the leaves the lesion/ spots first appear as minute brown specks,
and then grow to become spindle-shaped, pointed at both ends. The center
of the spots is usually gray or whitish with brown or reddish-brown
margin. Fully developed lesions reach 1-1.5 cm long, 0.3-0.5 broad.
Under favorable conditions, lesions enlarge and coalesce; eventually
kill the leaves.ii. Collar Rot:
Infection at the junction of the leaf blade and sheath in the typical
brown “collar rot” symptom. A severe collar rot can cause the leaf to
die completely. When collar rot kill the flag or penultimate leaf it may
have a significant impact on yield.iii. Neck Blast:
This occur when the pathogen infect the neck of the panicle to cause a typical “neck rot”
or rotten neck blast symptom. The infected neck is griddled by a
grayish brown lesion and the panicle falls down if the infection is
severe. If the neck blast occurs before the milk stage, the entire
panicle may die prematurely, leaving it white and completely unfilled.iv. Panicle Blast:
The pathogen also causes brown lesions on the branches on the panicles
and on the spikelets pedicles, resulting in “panicle blast”. Infection
of the neck, panicle branches, and spikelets pedicles may occur together
or may occur separately v. Node Blast:
The fungus may also attack the stem at nodes, node blast in which the
stem bend and break at the node causing spikelets sterility
সার্চ করুন
উত্তর সমূহ
The disease can be described based on the part of the plant infected as follow: i. Leaf Blast: On the leaves the lesion/ spots first appear as minute brown specks, and then grow to become spindle-shaped, pointed at both ends. The center of the spots is usually gray or whitish with brown or reddish-brown margin. Fully developed lesions reach 1-1.5 cm long, 0.3-0.5 broad. Under favorable conditions, lesions enlarge and coalesce; eventually kill the leaves.ii. Collar Rot: Infection at the junction of the leaf blade and sheath in the typical brown “collar rot” symptom. A severe collar rot can cause the leaf to die completely. When collar rot kill the flag or penultimate leaf it may have a significant impact on yield.iii. Neck Blast: This occur when the pathogen infect the neck of the panicle to cause a typical “neck rot” or rotten neck blast symptom. The infected neck is griddled by a grayish brown lesion and the panicle falls down if the infection is severe. If the neck blast occurs before the milk stage, the entire panicle may die prematurely, leaving it white and completely unfilled.iv. Panicle Blast: The pathogen also causes brown lesions on the branches on the panicles and on the spikelets pedicles, resulting in “panicle blast”. Infection of the neck, panicle branches, and spikelets pedicles may occur together or may occur separately v. Node Blast: The fungus may also attack the stem at nodes, node blast in which the stem bend and break at the node causing spikelets sterility