WEATHER DATA FOR THE PREVAILING WEEK

Date of Fruit Pruning: 15/09/2022

 Thursday (13/07/2023) – Wednesday (19/07/2023)

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.

II. Water Management

a. Number of days after foundation pruning: 89

b. Pan evaporation: 2 to 4 mm

Amount of irrigation advised:

1. All the grape growing regions are forecasted to receive from drizzling to light rains.The irrigation water application should be based upon the growth of the vines.In case rain exceeds 5 mm on a given day, irrigation water application can be skipped for that day.Generally, under wapsa (field capacity) condition of the soil, donot give irrigation.

2. If the soils especillay medium and heavy, are saturated with water, then, do not irrigate for atleast 5-7 days till the soil comes to wapsa condition.

3. Cane maturity stage:Apply irrigation through surface drip @ 2000 L/acre per day, if required only.

4. In rainy conditions, remove mulch cover on the bund and allow the rain water to seep into the soil. This will leach the accumulated salts in the rootzone.The mulch so removed can be mixed with the soil to improve the soil porosity.

Nutrient management

1. If the rootzone is saturated then donot apply any fertilizer. Growth will be slow, donot worry.As and when the soil comes into field capacity (wapsa), root activity will increase and the growth will progress.After that only fertilizer should be applied.

2. Due to continuous sprays the leaf will not look healthy, need based sprays should be followed as the leaf health is bound to affect the photosynthate formation.This will impact bunch development.

3. After current rains, give foliar spray of SOP @ 3-5 g/L depending upon canopy size.

4. In case of calcareous soils where acute iron deficiency is observed, repeatedly spray 2-3g/L Ferrous sulphate two to three times at 3 days interval followed by 15-20 kg/ acreFerrous sulphate application through drip.The fertigation dose should be split into atleast 3 doses of 5kg each.Apply 5kg/ acre soluble sulphur through drip every week.Also spray magnesium sulphate and potassium sulphate @ 3 gm each/ L once only.Keep a close watch on the development of leaf blackening symptoms if irrigation water contains sodium more than 100ppm.

5. Possibility of leaf curling, check the leaf margins, if slight to more yellow, possibility of potassium deficiency.Foliar spray of SOP @ 3-4g/L followed by fertigation of 20-25 kg SOP/acre in 2 to 3 splits.

6. In coloured varieties like Jumbo, Nanasaheb Purple etc., leaf curling along with reddening/ bronzing of the leaf margin can be observed if potassium deficiency is there.Foliar spray of SOP @ 3g/L followed by fertigation of 20-25 kg SOP/acre in 2 to 3 splits.

Cane maturity stage

1. Potassium application is required from Cane maturity stage onwards.Approx. 64 kg of sulphate of potash (soluble grade) should be applied in this stage.Split the application into atleast five doses to reduce the leaching losses of the potassium.Apply 15 kg SOP in two – three splits during this week.In calcareous soils, provide foliar application of Sulphate of Potash (@ 4g/L once in this growth stage.

2. Apply magnesium sulphate @ 15 kg/acre in two splits.The application should be done during 60-75 days after pruning.In calcareous soil, provide foliar application of magnesium sulphate @ 4g/L once in this growth stage.

3. The light intensity is reduced due to cloudy conditions, management of canopy to improve light penetration is important for cane maturity.

4. Two –three sprays of SOP@ 4-5g/L and Magnesium sulphate is required for improving cane maturity in the vineyards.

Pre-pruning operations – Fruit pruning season

1. In case pruning is planned during August - September, raise Sunnhemp or Dhaincha for green manuring purpose.

2. The vineyards where sodicity problems are there, apply gypsum to the soil for removal of sodium from the soil exchange complex.In case of calcareous soils, use sulphur for similar purpose.The application should be alongwith FYM/compost etc.They should be mixed in the soil and not left on the top.

3. In case of calcareous soils, if SSP is applied as basal dose, mix with FYM/compost etc. to avoid phosphorus fixation.

4. Test the soil and irrigation water, to plan for nutrient and water management during fruit pruning season.

III. Canopy Management

The practices followed during this week are as below.

1) The rains received during the last week will help to increase the relative humidity and thus the vigor of the vine. 

2) Shoot vigor will be more. Hence, shoot pinching should be taken up on priority basis. 

3) With the emergence of side shoots, the incidence of powdery mildew is expected. Hence, shoot pinching and training the shoot on wire should be done. This will help to reduce the relative humidity and maintain microclimate in the canopy.

4) Early cane maturity is important. Hence, shoot pinching and shoot training should be given priority. This will help to receive sunlight and proper aeration in the canopy.

5) Application of potash and reduction of irrigation water will also help to attain cane maturity in the vineyard.

6) In the vineyard the growers may experience milky white color of shoots at bottom. This is the indication of cane maturity. Reduction of irrigation and potassium spray will help to advance the cane maturity. 

7) Spraying of biologicals during humid conditions can help to control the disease incidence. 

8) Bark splitting at the basal portion of growing shoots is being experienced. This is nothing but the skin rupturing due to increased temperature and relative humidity. Hence, it will not have any adverse effect. 

9) Under humid condition, sprouting of main bud (tiger bud) is experienced by the growers. This problem is more prominent in the vineyard where the shoots just started maturing from the bottom. In such vineyards, either water shortage or excess use of cytokinin based PGR was used. With sudden increase in relative humidity, the increase in internal gibberelins in the vine resulting into vegetative growth. However, the controlled vigor due to this condition results into pressure on the immature portion ie., the bud. To control this, apply nitrogenous fertilizer mainly urea or ammonium sulphate @ 1.0 kg per care for 2-3 days. Do not pinch the shoots for two weeks but allow the growth of 4-5 leaf on shoot.

10) In the vineyard where cordon development is in progress, a second instalment can be done. The last shoot can be tied on the cordon. This shoot needs to be pinched at 4 to 5 leaf only. 

11) Application of PGR for fruit bud differentiation is necessary as prevailing weather is not favourable. Hence, 6BA and Uracil applications with recommended doses should be followed. 

12) Once the side shoots start emerging, spray of P and K grade fertilizer with a minimum dose of 2 to 2.5 g per litre of water can be given. 

13) In rootstock, shoot thinning can be undertaken. Retention of 3 to 4 healthy, straight growing shoots will be useful for grafting. 

14) The shoot thickness of rootstock should be 8 to 10mm at about 1.25 feet above the ground. 

15) The side shoots on rootstock should be removed in the instalment so that the required thickness for grafting can be achieved. 

16) The fertilizers containing P and K grade (eg. 12.61.0, 18.46.0, etc) need to apply in 2-3 split doses.

17) In the soil containing calcium carbonate, sulphur @ 40-50 kg per acre should be mixed with soil.

18) Spraying the vineyard with 0.5% Bordeaux mixture at the initiation of shoot maturity (milky white color stage of shoot) will help to achieve early cane maturity and disease control.

IV. Disease management

Anthracnose is incident in many locations and application of carbendazim/ Thiophenate methyl@ 1g/L may be done. The spray may be repeated after 7 days. If the problem persists, application of hexaconazole @0.75ml/L may be given to control anthracnose. Additionally, it will control powdery mildew infection, if any. Preventive application of Mancozeb and Copper formulations to be continued and it will take care of bacterial spot as well. Drip or foliar application of Trichoderma may be given during this week as moist and humid conditions will help in multiplication of the biocontrol agents. Streptocycline should NOT be applied for any bacterial diseases. Excess application of copper may be avoided. Spraying has to be done when there is no rains for at least 1.5-2 hours.

V.Insect and Mite management

1. Due to reduction in temperature and cloudy conditions, mealybug infestation may be noticed. Use of broad spectrum insecticides should be avoided for mealybug control. Buprofezin 25 SC @ 1.25 ml/l water may be given to manage mealybugs. Preventive plant wash, on stem and cordons, of biocontrol agents such as Verticillium, Metarhizium, Beauveria may be given. In case of mealybug infestation on canes, foliar application of imidacloprid 17.8 SL @ 0.4 ml per litre water should be given.

2. In case of thrips or caterpillar infestation, remove excess canopy. Application of fipronil 80 WG @ 0.0625 g per litre or emamectin benzoate 5 SG @ 0.22 g per litre water is effective. Light traps may be installed outside the vineyards to manage moths for reducing caterpillar infestation.

3. Mite infestation may start appearing, therefore, monitor the vineyards carefully. If mite infestation is observed, sulphur 80 WDG @ 1.5- 2.0 gram per litre or abamectin 1.9 EC @ 0.75 ml/l water is effective.

4. Red colour stem borer (Dervishiya cadambae) has started egg laying and infestation under bark in grape areas. Install light traps near the vineyards to manage moths of this stem borer. Remove loose bark from stem and cordons and give preventive wash on stem and cordons with biocontrol agent Metarhizium @ 3-5 ml per litre water minimum once in the month during July to September months. If infestation is observed, remove the loose bark and give stem and cordon wash with Metarhizium @ 3-5 ml per litre water and 1.5-2 litres water per plant.