1.

Project Code

:

PRP- 3173

2.

Title

:

Management of mulberry diseases  

3.

Investigators

:

Govindaiah, Sharma DD, Naik VN,  Mala VR, Chowdary NB, Gupta VP, Das PK, Katiyar RS

4.

Project period

:

May 2000 - March 2004

5.

Institute/ University

CSR&TI, Mysore

6.

Project cost

:

3.16 lakh

7.

Objectives

• To evolve an effective technology for mulberry diseases (leaf spot and leaf rust) management through activation of plant defense mechanisms.
• To develop an eco-friendly methods for the management of root knot and root knot diseases of mulberry.
• To work out the economic threshold level (ETL) for major foliar diseases (leaf spot and leaf rust) of mulberry for need based application of chemical control measures.

8.

Important findings

Eighteen PGPRs, belonging to Azotobacter, Bacillus and Pseudomonas isolated from mulberry rhizosphere, were evaluated for their impact in inducing systemic resistance in mulberry against leaf spot and leaf rust. Combined application of A. chroococcum Azc-3 + P. fluorescens Psf-4 mixing with FYM (1:1:50) @ 20 kg/ha/crop in two split doses (I^st dose immediately after pruning and II^nd dose after 20 days of 1^st dose) during rainy and winter, were found effective in inducing SR against both the diseases by reducing severity of leaf spot by 90.51% and leaf rust by 68.21% and prevents leaf yield loss up to 15-25 %.

Combined application of VAM + Bionema along with neem oil cake reduced the root knot severity  by 94.3 % with 29.2 %, prevention in leaf yield loss.

Among isolates of Pseudomonas fluorescens Psf-7 was found most effective against all the pathogens. Combined application of Psf-7 in with Trichoderma harzianum was found effective against root rot with 70-75% control over check.

Severity of leaf spot was found progressing 35-40 days and leaf rust 45-50 days after pruning. MR-2, S-13 and V-1 are found resistant against leaf spot. The predicted disease severity index (Y) for leaf spot is Y = 7.09 + 0.59** (DAP) – 1.07* (Max. temp) with R² = 0.86 (where DAP indicates days after pruning). Prediction for disease severity for leaf rust is Y = - 66.18 + 0.80** (DAP) + 0.45* (AH) with R² =0.78 (where Y = Disease severity and AH = the average humidity). To keep the pathogens below ETL (5% PDI) spraying of 0.2% Bavistin for leaf spot and Kavach for leaf rust on 30^th and 40^th   day, respectively are recommended.