WEATHER BASED GRAPE ADVISORY

 WEATHER DATA FOR THE PREVAILING WEEK

Date of Fruit Pruning: 15/09/2022

Thursday (15/12//22)–Wednesday (21/12/2022)

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 : 91 days

B)    Pan evaporation: 3 to 4 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 @ 5040-6720 L/ acre/ day for all grape growing regions.  In case vigour is more than desired, then reduce irrigation water application by half to 2500 - 3500 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.        During Flowering to setting stage, apply irrigation through drip @ 2000 to 3000L/ acre/ day.  Further, in case vigour is more than desired, then reduce irrigation water application by half.

5.       During Berry development stage, apply irrigation through drip @ 5040-6720 L/ acre/ day for all grape growing regions

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

NIL

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

During the last week, the weather in all grape growing areas is clear. The day temperature is increasing while the night temperature remains the same as that of last month. The problems faced by the grape growers during this weather and the probable solution is given below.

1.        The temperature in some areas during the night is decreasing. Due to this the root activity is getting hampered. The growers are applying more irrigation for canopy. The roots may become black with continuous and excess irrigation. Hence, the irrigation needs to be minimized and based on the transpiration and  vine growth stage should be applied. 

2.        The grape growers are spraying more PGR in addition to the biostimulants available in the market. This is resulting in coiling of the bunch even at pre-bloom stage. To avoid, the PGR dose should be only based on the recommendation. The pH of the spray solution need to be verified before use for better result and efficiency of the PGR. 

3.         In many of the grape vineyards, the leaf is becoming yellow at the margin. This is mainly due to the deficiency of magnesium. The petiole test at flowering will support to know the present status of the vine. Green veins and the rest portion is yellow might be due to ferrous deficiency. Spraying of ferrous and magnesium will help to control these problems. 

4.        In the late pruned vineyards, the canopy requirement should be considered. The requirement of leaf for bunch development can be completed before the berry setting. To achieve the required canopy, the nutritional doses need to be taken care of. 

5.        During the cloudy time, there will be powdery mildew incidence. The disease may be controlled using biologicals mainly in the vineyards where berry setting is over. 

6.        In the vineyard being managed for export, the bunch thinning should be given the priority. Maintaining 100-120 berries in a bunch will help to achieve 4.5 to 5.0 gram berry weight. 

V. Disease management (Dr. Sujoy Saha)

Incidence of powdery mildew may be observed in many locations especially in berries.

Application of hexaconazole or difenoconazole or tetraconazole or cyflufenamid or Fluopyram +

tebuconazole or Fluxapyroxad+ Difenconazole will control powdery mildew. A new fungicide

Polyoxin D zinc salt 5% SC @ 600ml/Ha will also give good results against powdery mildew. A

tank mix of triazoles with potassium bicarbonate @5g/L will help in increasing the efficacy of

the fungicides. 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.

However, for exports to China, the use of potassium salt of activated phosphorus and fosetyl Al

may be restricted.

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

Growth stage: Berry development stage after October Pruning

Growth Stage: Berry development stage after October pruning.

1.      Emamectin benzoate 5 SG @ 88 gram per acre or cyantraniliprole 10 OD @ 0.7 ml per litre water is effective against Spodoptera caterpillars.

2.      Buprofezin 25 SC @ 1.25 ml per litre water or spirotetramat 15.31 OD @ 280 ml per acreare effective against mealybugs. Soil drenching with clothianidin 50 WDG may also be given for mealybug management. Entomogenous fungus such as Metarhizium, Beauveria and Lecanicillium can be used for plant wash to reduce mealybug populations.

3.      Bunch webbing caterpillars may start damaging bunches in most of the grape areas wherehumidity 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 tobe 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.

4.      Sulphur 80 WDG @ 1.5-2.0 g/L water may be applied if mite infestation is observed.