TNAU scientists observe Quick Wilt Disease in black pepper growing regions

Coimbatore: Tamil Nadu Agricultural University Scientists have observed quick wilt incidence in the black pepper growing areas due to the prevailing weather conditions.

The foot rot disease (quick wilt disease) is caused by a fungus named Phytophthora capsici. This pathogen infects all parts of black pepper like leaf, stem, spike, collar and root.

Infection on leaves appears initially as water soaked lesions, which then expand rapidly into dark brown patches with fimbriate margin and sometimes has a greyish center.

Foliar infection leads to varying degrees of defoliation which depends on the severity of the disease. Infection also occurs on spike resulting in spike shedding.

On tender and woody stems, infection occurs as dark wet spots resulting in progressive rotting leading to die-back symptoms.

Collar and root infections are the most serious and generally infect the vine causing rapid wilting, defoliation and quick death of vine. The collar (foot) infection spreads upwards and downwards resulting in rotting of stem and roots. The collar infected vines show yellowing, flaccidity of leaves, defoliation, spike shedding, breaking and rotting of stem at the nodal regions.Root infection may start from the feeder root system or it may spread downwards from collar infection.

Scientists from TNAU say that an integrated approach involving phytosanitation, appropriate cultural practices, preventive measures added with timely chemical control measures are necessary for successful management of the disease.

They say that the Phytosanitation process involves, planting disease free cuttings in new plantations, destruction of infected plant materials by burning, treatment of basins with fungicidal drenching, lime application etc. Cultural practices involve timely tying or pruning of the runner before north east monsoon, mulching the basins to prevent rain splash, prevention of water stagnation and facilitating proper drainage in the plantation.

Here are some measures that are need to be taken for the successful control of this disease:

Remove the severely infected vines immediately and apply 1 kg lime in the infected root zone areas.Fresh planting may be taken up 1-2 months after lime application. Use nematode-free planting materials for new planting.

Provide adequate drainage facilities.

Apply neem cake @ 1 kg/vine during summer months Apply bio-control agents viz., Trichoderma, Bacillus subtilis and Pochonia chlamydosporia as consortia @ 10 gm each per plant once in three months (or) soil drenching with 1% Bordeaux mixture or copper oxychloride @ 0.25% or copper hydroxide @ 0.2% or metalaxyl + mancozeb @ 0.15%.