WEATHER BASED GRAPE ADVISORY

WEATHER DATA FOR THE PREVAILING WEEK

Date of Fruit Pruning: 15/09/2022

Thursday (19/01/2023)–Wednesday (25/01/2023)

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 and Dr. Yukti Verma)

a. Number of days after fruit pruning: 134 days

b. Pan evaporation: 4-5 mm

Amount of irrigation advised (Dr. A.K. Upadhyay):

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 Flowering to setting stage, apply irrigation through drip @ 2200 to 3000L/ acre/ day.  Further, in case vigour is more than desired, then reduce irrigation water application by half.

4.      During Berry development stage till harvesting, apply irrigation through drip @ 6800- 8500 L/ acre/ day.   

Soil and Nutrient management

Flowering to setting stage:

1.      Inflorescence necrosis could be a issue in dense canopy. Remove side shoots and reduce canopy to allow penetration of the sunlight for proper aeration.  Manage canopy for adequate sunlight and air movement within the canopy for avoiding/ minimizing problems of kooj (inflorescence necrosis).

2.      Apply 3-4 kg Phosphoric acid in two to three splits this week.  Remember that the pH of the irrigation water should be near 6.0.

3.      Petiole nutrient testing: At 70% capfall stage, petiole samples should be taken for nutrient analysis. The leaf opposite the bunch should be removed for sampling.

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)

Growth Stage: Berry development stage to veraison after October pruning

1.      The temperature during day time is increasing while the night temperature is decreasing. This is increasing the water requirement of vine. Mulching on the bund will help to reduce the requirement. 

2.      Irrigation during ealy morning or evening should be preferred. 

3.      Many gardens are facing the problem of sun burn. Bunch covering,  use of shade net and bringing the bunches under canopy shade will support to reduce the incidence.

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 Ampelomycesquisqualis @5g/L or two sprays of Bacillussubtilis @2g/L may be given for powdery mildew prevention. Bacillussubtilis will also help in bioremediation i.e. reduction of pesticide residues to some extent. Application of hexaconazole or difenoconazole or tetraconazoleor 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: Berry development stage to veraison after October pruning

1.      Mealybug, thrips, mites and caterpillar population may be noticed due to favourable weather conditions. However, in Nashik and Pune region mealybug population growth may reduce due to decrease in low temperature temporarily.

2.      Buprofezin 25 SC @ 1.25 ml per litre water (PHI 65 days) is effective against mealybugs. Soil drenching with clothianidin 50 WDG (PHI 60 days) may also be given for mealybug management after ensuring proper white root development for uptake. Entomogenous fungus such as Metarhizium, Beauveria and Lecanicillium can be used for plant wash to reduce mealybug populations. If PHI with above insecticides 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.

3.      Remove excess shoot growth to manage thrips. If pesticide application is necessary, then abamectin given for the management of mites will also control thrips.

4.      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.

5.      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.

6.      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.

7.      Some areas may see aphid infestation on bunches. Imidacloprid 17.8 SL @ 0.4 ml per litre (PHI 60 days) may be sprayed.