Weekly advisory 26 January, 2023 - 1 February, 2023

WEATHER DATA FOR THE PREVAILING WEEK

Date of Fruit Pruning: 15/09/2022

Thursday (26/01/2023) – Wednesday (01/02/2023)

Note: Above weather information is summary of weather forecasting given in following websites

https://www.wunderground.com/?cm_ven=cgi

https://imdagrimet.gov.in/weatherdata/BlockWindow.php

https://www.timeanddate.com/weather/india

ICAR-National Research Centre for Grapes does not claim accuracy of it.

Water management (Dr. A.K. Upadhyay) :

Pan evaporation: 4-5mm

Amount of irrigation advised:

1. In case the soil is under wapsa (field capacity) condition, donot irrigate the vineyard.
2. Practice mulching to keep the bunds moistened. This will reduce the salinity build up in the root zone due to evaporation of the moisture from the surface of the bund.
3. During Berry development stage till harvesting, apply irrigation through drip @ 6800- 8500 L/ acre/ day.

IV. Soil and Nutrient management:

Berry Development stage:

1. If the berry size is from 2-4mm, spray calcium @ 2g Calcium Chloride or 0.5 g Ca chelate per litre. Target sprays immediately after GA application (preferably next day) for better absorption.
2. If the berry size is from 5-8mm, spray calcium & 2g Calcium Chloride or 0.5 g Ca chelate per litre. Target sprays immediately after GA application (preferably next day) for better absorption.
3. Apply magnesium sulphate through drip @ 10kg/acre from 8-10mm berry size.
4. Foliar spray of sulphate of potash @ 3g/acre at 8-10mm berry size.
5. After 8-10 mm berry size, start application of nitrogen in the form of ammonium sulphate @ 25kg /acre in 4 splits in calcareous soil and as urea @ 15 kg/acre in other soils in 3 splits. Follow this up with Sulphate of potash or 0-0-50 @ 25 kg/ acre in 3-4 splits for next two weeks.
6. If soils are calcareous, then apply zinc sulphate and ferrous sulphate @ 5-10 kg/acre at 65-70 days after pruning.
7. Possibility of powdery mildew infection. Build up potassium levels in grapevine either through foliar spray @4-5 gm SOP/L and drip @ 15 kg SOP/L if not applied since last 20 days.

Ripening to Harvest stage:

1. Apply Sulphate of potash or 0-0-50 @ 25 kg/ acre in 3-4 splits for next two weeks. Total potassium application (SOP) should be approx. 60 kg/acre during this stage. Follow this up with Magnesium sulphate @ 10 kg/acre in two splits.
2. Spray Magnesium sulphate and potassium sulphate @ 4g/L in calcareous soil.
3. Possibility of powdery mildew infection. Build up potassium levels in grapevine either through foliar spray @4-5 gm SOP/L and drip @ 15 kg SOP/L if not applied since last 20 days.
4. Manage canopy for adequate sunlight and air movement within the canopy for avoiding/ minimizing problems of berry cracking.

III. Requirement of growth regulators (Dr. S.D. Ramteke)

NIL

IV. Canopy Management (Dr. R.G.Somkuwar):

The day temperature in the grape vineyard is increasing while the night temperature is decreasing.　 This will make some problems in the vineyard.　

1) There will be sudden increasing demand for water by the vine.

2) The rate of water loss through transpiration　 will be more. This will demand more water.

3) If the water availability is increased, there may be build up of microclimate favorable for powdery mildew infection.

4) Cloudy condition may also favors the development of powdery mildew.　

5) The same condition may also disturb the balance of source:sink thereby inviting another problem of cluster necrosis.　

6) Water availability should be strictly based on berry development stage. At　the harvesting stage, water requirement should be less to advance TSS in the grape berries.　

7) The irrigation to the grape vineyard be managed either during morning or evening. This will reduce the water .

8) Dripline can be brought to the ground surface.　

9) Mulching to be followed to utilize available irrigation water.　

10) Antistress can be sprayed @ 3 to 4 ml per litre water.　 This will help in reducing the water losses from leaf.

11) Nutrient management and irrigation should be followed to avoid cluster necrosis.　

12) Preparation for re-cut to be started as the temperature is rising.　

V. Disease management (Dr. Sujoy Saha)

Powdery mildew in berries may be observed in this stage and in some cases where paper wrapping is done, some symptoms may be visible in the leaves. One application of Ampelomyces quisqualis @5g/L or two sprays of Bacillus subtilis @2g/L may be given for powdery mildew prevention. Bacillus subtilis will also help in bioremediation i.e. reduction of pesticide residues to some extent. Application of hexaconazole or difenoconazole or tetraconazole or cyflufenamid or Fluopyram + tebuconazole or Fluxapyroxad+ Difenoconazole will control powdery mildew and may be given in the crop which is relatively late i.e. around 70-80 days . A new fungicide Polyoxin D zinc salt 5% SC @ 600ml/Ha will also give good results against powdery mildew. The bunch load needs to be maintained for proper coverage of fungicides. Use of sulphur @2.5-3g/L needs to be enhanced in between triazole sprays.

VI. Insect and Mite management. (Dr. D.S. Yadav)

Growth Stage: Veraison to post veraison stage after October pruning

• Mealybug and mites population may be noticed due to favourable weather conditions.
• Buprofezin 25 SC @ 1.25 ml per litre water (PHI 65 days) is effective against mealybugs. If PHI with above insecticide is not available, then spot plant wash with trisiloxane polyether surfactant @ 0.3 ml per litre water with 10-12 litre water per plant to remove mealybug and honeydew from plant and bunches in the field can be given followed by wash with water.
• Mite infestation may increase in most of the grape areas. Sulphur 80 WDG @ 1.5-2.0 g/L or Abamectin 1.9 EC @ 0.75 ml/L (PHI 30 days) or Bifenazate 22.6 SC @ 0.5 ml/L (PHI 30 days) water may be applied if mite infestation is observed.
• All the cracked/damaged berries should be removed from the grape bunches. These berries should be destroyed by burying them minimum two feet deep in the ground away from the vineyards. It will reduce the scavenging fly population in the vineyard. Ripe banana can act as a good attractant for these scavenging flies. Therefore, banana traps can be made and installed at the rate 5 per acre. To make a banana trap, take a container with small holes at sides and put a fully ripe banana inside it cut into pieces. Pour 2-3 drops of spinosad 45 SC on the banana. Cover the mouth of the container with inverted paper-cone keeping a small hole at the bottom for fruit flies to enter. The berry cracking of grapes should be managed by following suitable viticultural practices.
• Remove excess shoot growth to manage thrips. If pesticide application is necessary, then abamectin given for the management of mites will also control thrips. Emamectin benzoate 5 SG @ 88 gram per acre or cyantraniliprole 10 OD @ 0.7 ml per litre water is effective against Spodoptera caterpillars and thrips.
• Bunch webbing caterpillars may start damaging bunches in most of the grape areas where humidity is high. The most effective way to control them is to collect and kill them by hand as insecticides may not reach inside the bunch. The caterpillars on leaves are also needs to be killed as they can go inside the bunch later on. Spraying of emamectin benzoate 5 SG @ 0.22 gram per litre water or cyantraniliprole 10 OD @ 0.7 ml per litre is effective to manage them.
• Some areas may see aphid infestation on bunches. Imidacloprid 17.8 SL @ 0.4 ml per litre (PHI 60 days) may be sprayed.