WEATHER BASED GRAPE ADVISORY

WEATHER DATA FOR THE PREVAILING WEEK

Date of Fruit Pruning: 15/09/2022

Thursday (24/11//22)–Wednesday (30/11/2022)

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.  

II. Water management (Dr. A.K. Upadhyay & Yukti Verma)

A)    Days after fruit pruning : 70 days

B)    Pan evaporation: 4 to 5 mm

Amount of irrigation advised:

1.      In case soil is under wapsa (field capacity) condition, donot irrigate the vineyard.

2.      During shoot growth stage (Fruit pruning season),  apply irrigation through drip @ 6800-8500 L/ acre/ day for all grape growing regions.  In case vigour is more than desired, then reduce irrigation water application by half to 3500 - 4200 L/ acre and still if growth is more, stop the irrigation till such time the growth is brought under control and then start irrigation.

3.      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.

4.      From flowering to fruit setting, apply irrigation through drip upto 3000 L/ acre/ day.  Vigour needs to be controlled.

5.      During Berry development stage, apply irrigation through drip @ 6800-8500 L/ acre/ day for all grape growing regions.

Nutrient management

1.      Manage canopy for adequate sunlight and air movement within the canopy for avoiding/ minimizing problems of kooj (inflorescence necrosis).

2.      Unnecessary sprays should be avaoided as the leaf health is bound to affect the photosynthate formation.  This will impact bunch development.

Shoot Growth stage

1.      Based upon the soil test value, during shoot growth stage apply urea @ 15kg / acre this week in two splits.  If the soil is calcareous, instead of urea apply ammonium sulphate @ 25 kg/ acre in three splits this week.  Depending upon the crop vigour, regulate nitrogen application.

2.      If sodicity problem is there, apply 10 kg Sulphate of potash per acre in 2 splits this week.

3.      Until and unless leaves are fully developed donot go for any foliar application of nutrients. It will be lead to wastage of spray.

4.      The quantity of nutrients to be applied through foliar, depends upon canopy size. 

5.      If the crop is between 5 leaf to prebloom stage, apply Zinc sulphate and Ferrous sulphate @ 15 kg/ acre based upon soil test value.  Boron application should be carried out only if soil test value indicates low levels and the irrigation water does not contain boron.  If during foundation puning, the petiole test stated that boron was deficient then apply boron @ 1.5 kg to 5 kg depending upon the soil test value.  Apply one kg boron at a time.

6.      Apply 15 kg Magnesium sulphate per acre in two splits.

7.      If soils are calcareous, spray Sulphate of potash and Magnesium sulphate @ 2-3g/L depending upon leaf age during prebloom stage. 

8.      Minimum temperature predicted is low in some grape growing areas viz. Nasik, Pune, Jalna, Ahmednagar, Solapur etc.  The growth will be slow.  If not sprayed go for foliar spray of Sulphate of potash @ 2-3g/L depending upon leaf age during prebloom stage and apply through drip 15-20 kg SOP/ acre.  This helps in stress management. 

Flowering to setting stage:

1.      Donot apply any nitrogen based fertilizer just before Flowering to Setting stage to avoid 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. OR apply SSP @ 125kg/acre as basal application.  SSP should be mixed with FYM/Compost before application to minimize phosphorus fixation.

3.      If SOP not applied, then apply 15 kg SOP in case low temperature and cloudy conditions forecasted during flowering stage.

4.      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.      After Berry setting, continue initially with Phosphoric acid application @ 2 kg followed by 5 kg 12-61-0/acre. 

2.      If the berry size is from 2-4mm, spray calcium @ 2g Calcium Chloride / Calcium Nitrate per litre.  Target sprays immediately after GA application (preferably next day) for better absorption.

3.      If the berry size is from 5-8mm, spray calcium @ 2g Calcium Chloride / Calcium Nitrate per litre.  Target sprays immediately after GA application (preferably next day) for better absorption.

4.      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.

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

NIL

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

1.    The minimum temperature in the vineyard is reducing. This will affect the berry development. Hence, the irrigation in vineyard in the berry development stage should be given sufficient irrigation to maintain the temperature. 

2.      For berry development,  10 to 12 leaf with 160 to 170 sq.cm.is required.  Hence, canopy development should be considered important during pre-bloom stage.

3.      During the low temperature period,  the shoot may not be sufficient. The shoot vigor can be achieved till berry setting stage. Hence, considering the canopy vigor,  nitrogenous fertilizer need to be used.

4.      The root activity will not be proper under low temperature period. Hence, making a small trench just near the bund or loosening the soil on bund will help for better aeration and formation of new roots required for berry development.  

5.      Care should be taken that only 10 percent roots are cut by making a trench. The irrigation for development of these new roots is required. 

6.      During the pre bloom spray, pH of GA3 spray solution needs to be maintained to 5.5 to 6.0. To maintain,  citric acid or urea phosphate can be added. 

7.      Under the condition of morning dews, leaf wetness will be for longer time. This may lead to downy mildew infection. Hence care should be taken for open canopy. 

V. Disease management (Dr. Sujoy Saha)

Powdery mildew may be disseminated by the rain splashes and initial symptoms may be observed as soon as the rain stops. Application of triazoles like hexaconazole or difenoconazole or cyflufenamid or Fluopyram + tebuconazole or Fluxapyroxad+ Difenconazole will control powdery mildew. Foliar application of Trichoderma @ 2-3g/ml should be given during this time to get a control against anthracnose and downy mildew. One application of Ampelomyces quisqualis @5g/L or Bacillus subtilis @2g/L may be given for powdery mildew prevention. No mixing of fungicides and biocontrol agents should be done. Some downy mildew are observed in the berries in some locations and at this stage potassium salt of activated phosphorus @4g/L+ Mancozeb @ 2g/L may be applied. 

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

Growth Stage: flowering, berry setting to berry development after fruit pruning

1.      In case of caterpillar and thrips infestation, application of emamectin benzoate 5 SG @ 0.22 g per litre or cyantraniliprole 10 OD @ 0.7 ml per litre water is effective.

2.      For flea beetle management, Imidacloprid 17.8 SL @ 0.4 ml/L or spinosad 45 SC @ 0.25 ml per liter water at night is effective.

3.      Vineyards may have moderate mealybug infestation as well. Do not spray any broad spectrum insecticides such as chlorpyrifos, dichlorvos, methomyl, profenophos, etc. for mealybug control. Higher humidity will favour development of natural enemies which will slowly kill mealybugs. In case chemical spray is required, prefer buprofezin 25 SC @ 1.25 + Metarhizium anisopliae 3 ml per litre of water for plant wash.

4.      Incidences of new species of stem borer (red colour larva) may be noticed under bark in Sangali, Solapur, Nashik, Pune, Bijapur grape areas. Remove the loose bark and give good plant wash mainly targeting cordons and main trunk with Metarhizium anisopliae @ 3 ml/l.