Many scientific activities done at MRDBS have benefited the growers in using chemical and organic fertilizers / manures judiciously.
1 Setting up soil fertility norms for grapes in Maharashtra for Thompson Seedless, its various mutants and Sharad Seedless. Based on the nutrient requirement of the grapevine the soil fertility norms for grapes are formulated. This has surprisingly proved effective in the production of quality grapes for export purpose
2. Petiole nutrient norms for Thompson Seedless grape The petiole nutrient norms are developed separately at bud differentiation stage and bloom time.
3. Integrated nutrient management for potential yield & quality of grapes Frequent changes in the nutrient recommendation were made by considering the analytical report. Taking into consider the specific developmental stages of grapevine, specific guidelines have been developed for giving most accurate advice.
4. Fruitfulness of buds. 15 days prior to fruit pruning the canes were dissected and after observing the fruitfulness level of pruning is advised to the grape growers.
5.Raisin Making Large number of trials were conducted viz, Hot water dip method, fumigation of tested grapes, oven drying, shed drying, different dipping oil formulation for dipping of fresh grapes, preparation of sheds for drying, size grading, packing, storage, transportation & marketing and a suitable method amongst these was suggested to the growers. This resulted in reduced import of raisins initially and over a period of years raisin import was completely stopped.
6.Introduction of Rootstock The use of rootstock was increased dramatically in the year 1997-98 & around 60% of total area was under the use of rootstock. Viticulture in Maharashtra was revolutionized by the use of rootstock as it helped in overcoming the problems like resistance to soil borne fungi & pests, salt and drought tolerance and imbalanced nutrition.
7.Varietal Trials Considering the needs of the domestic market as well as export, it was felt that introduction of some new varieties was essential, as only Thompson seedless variety was only grown.
Following varieties were introduce
A) White varieties
B) Black variety
3. 2A Clone
4. Italion Seedless
8. Use of mulches in viticulture Two types of mulches namely straw mulches and plastic mulches were used which reduced the moisture loss to the extent of 40%.Numbers of trials were conducted at various location & 90% of growers in drought prone area have adopted this technique.
Similarly due to construction of ponds at vineyard sites proved to be useful in saving the vineyards during critical stages without reduction of yield.
9. Integrated Pest management Growers were trained & advised for use of certain entopathological fungi like Verticilium lacanni for control of mealy bugs. Uses of Trichoderma harzianum, Beauveria bassiana were adviced for control of roots & Soil borne fungus.
10. Residue Monitoring activities This being a most sensitive & delicate issue, MRDBS in collaboration with NRCG, APEDA, NIB and State Department of Agriculture worked out a plan for the use of insecticide and fungicide to satisfy the market demands. This has been reviewed finely and suitable modification in the list of approved insecticide and pesticides were brought to the notice of growers through joint meetings newspaper, publications and magazine.
11. Effect of Gibberellic Acid on berry and berry weight, bunch thinning and berry setting in Thompson Seedless The research trial was conducted at the Manjri Farm, Pune in 2004 – 05. It was observed that application of 40 ppm Gibberellic Acid at the time of flowering resulted in well thinned bunches. Application at flowering reduced fruit set and there by thinned the bunches than the application at shatter. The treatment of 40 ppm Gibberellic Acid increased the weight of berries and improved quality
12. Variability in Soil fertility status in drip irrigated vineyards. The above experiment was conducted in Thompson Seedless vineyard at Manjri Farm. Surface soil samples at 0 cm to 60 cm at an interval of 6cm on both sides of emitters were collected and analysed in the laboratory. It is recommended to collect samples and 30 cm away from the emitters at 30 cm depth which represents the mean of parameters under test.
13. Multilocational trials on fertigation for viticulture Multilocational trials were conducted in major grape growing areas of Nashik, Pune, Solapur and Sangli. Various grades of water soluble fertilizers like 12:61:0, 19:19:19, 0:52:34 and 0:0:50 were used for fertigation and Single Super Phosphate, Urea, Diammonium Phosphate and Sulphate of Potash were used for soil application. The average of all these 16 trials conducted revealed that the total cost involved for fertilizers application through fertigation is reduced considerably (35 per cent). The labour charges are also minimum in fertigation. The overall increased in the grape production is to tune of 19.19 per cent. The cost involved in production of 1 kg of grape in case of fertilizer application through soil is Rs. 2.03, where as it is reduced up to Rs. 1.10 by adopting fustigation other advantages of fertigation are identified as, increase in fertilizer use efficiency, reduction in fertilizer doses, saving in labour cost, fast and convenient way of operation.
14. Effect of Hydrogen Cyanamide on release of dormancy of grape vine buds. The above field trial was conducted at Sonewadi (Nashik) in 2004 – 05 using Thompson Seedless grafted on Dogridge as well as on root. Uniform sprouting of 6-8 mm diameter canes were observed in both vines i.e. on root stocks and grafted on Dogridge and own roots. The sprouting was uniform and advanced by about 10 – 12 days as compared to non treated control.
15. Effect of saline water irrigation on soil and quality of grapes Four vineyards in Nashik division having highly saline water as source of irrigation were selected. The water, soil and petiole samples from each garden were analysed by adopting standard methods.
Considering the total salts in the irrigation water it was found that all the sources were harmful for proper growth of grapevines. In connection was highest in vineyard No. 4. Hazordous salts viz, sodium and chloride were also found to be highest (17.68 & 19.40 mcl) in water used for vineyard no. 4, followed by the water for vineyard no. 3. The movement to divalent ratio (kelley's ratio) also followed the same trend. The ca/p and k/p ratios in soil, petiole of skin were found in vineyard 3 & 4, thereby showing low concentration of phosphorus. Low acidity (0.68 g/100 g), higher TSS (23%) & high anthocyanins (0.116) were observed in comparison to garden 4, where the incidence of Pink berry formation was maximum to the tune of 80%.
16.Use of biological insecticides for the control of thrips. Studies were undertaken to see the effect of some of the biological insecticides on control of thrips at Manjari Farm, Pune. Azadiractin 50,000 ppm & 30% oil based were used at 30 ml/ 100 liters of water. It was observed that in the grape vines were Azadiractin was sprayed at an interval of every 3 days, the control of thrips after three sprayings was 7.84% which later reduced to 0% after 4th spraying. Where cow urine was sprayed at an interval of every three days, thrips population reduced from 5.29% to 0.09% after 5th spray.
17.Survey of grape disorders in Maharashtra.
1.Pink berries : Pink colour development in the skin of non pigmented cultivar of Thompson Seedless and its mutant viz, Tas-A-Ganesh, Sonaka, Manik Chaman was observed since last decode, resulting in flaccid berries with bitter taste, which are inferior for raisin making & for processing & result in loss of 80 -100 crores per annum. It was logically thought that antiethylene & ABA group of hormones viz, auxins delay ripening & regulate pink color formation. Observations recorded attributed 2 CEPA & ABA for an increase in pink berry formation. Any nutrient could not be targeted for pink berry formation, but needless use of calcium & M excess resulted in pink berry formation. High potassium in the skin may also aggravate pink berry formation.
2.Stalk necrosis / pedicel girdling / water berries : All the three disorders are late season maturity disorders related to each other, finally resulting in scattered water berries in the bunch causing severe losses. Imbalances in nutrients like Nitrogen, Potassium, Calcium and Magnesium leads to these disorders.
3.Sun Scorching: This is the major disorder observed during veraison causing considerable losses to growers. Excessive use of CPPU, Brassinostreoids and other potent PGR's are responsible for total collapses of bunch due to burning of tissues by sunrays and PGR'. Heavy incidences of thrips also result in scorching. Color forming pigments like chlorophyll, anthocyanins, carotenoids are affected due to sun rays, resulting in basic changes in composition of berry skin focus on flavanol content of berries during and after veraison needs to done.
Overall a systematic research trials on various disorders is required to come to a final conclusion and thereby suggest appropriate control measures.
18.Effect of Forchlorfenurn (CPPU) on berry development. A field trial was conducted in vineyard at Narayangaon in 2005 – 06 using Tas – A – Ganesh as test variety. Highest mean berry development and weight were recorded by application of GA3 30 ppm + CPPU 2 ppm. Berry development in respect to size, weight, length was significantly superior over control, indicating that CPPU acts sypergistically with GA3 in improving berry development.
19.Ferility status and nutrient indices of grape growing regions of Maharashtra. 9329 soil samples were collected from Nashik, Pune, Sangli, Solapur region and analysed for nutrient status. The average fertility of these was then computed.
It is revealed from the nutrient indices that the soils of Nashik region were deficit in organic carbon. Soils from Nashik, Pune & Solapur region were found to be deficit in available N content with fertility index less than 1.50. Nutrient index of all four regions was in the range 1.50 to 2.50 showing sufficiency of phosphorus, potassium, Sulphate, Iron, Manganese & Zinc. In case of calcium, magnesium and copper the nutrient indices were more than 2.50 indicating their high concentration.
20.Nodaltileges and Berry Stalk necrosis disorder in grapevine and solutions – A success story. Vineyards from Haveli Tahsil, Pune was selected. It was found that total Nitrogen and Magnesium content in rachis and pedicel are mainly responsible for the disorder. Total Nitrogen in rachis and in pedicel was very high in affected bunches over the non affected ones. The magnesium content is very low in both affected and unaffected rachis as well as in pedicel. Visual symptoms of Boron deficiency were also noticed and hence Boron application through foliar sprays was recommended. The growers were advised two sprays of magnesium Sulphate and Boric acid within a period of 8 days and one spray of sodium molybdate in the same period.
21.Studies on the pink berry disorder during ripening of the non –pigmented Thompson Seedless (Vitis vinifera L.) grapes in Maharashtra. The various PGR's tested have remarkably influenced the pink berry formation in Thompson seedless grapes. The PGRs i.e. 4 CPA, NAA and CPPU regulated the anthocyanin formation while CEPA and ABA induced the Pink berry formation in Thompson Seedless grapes during maturation.
Among the nutrient solution tried dipping the clusters in Phosphorous solution resulted in restricting the Pink berry formation dipping the clusters in nitrogen solution have recorded the highest Pink berry formation at maturity.
To confirm the results obtained in the field, cell suspension studies were also performed. Effect on DFR activity in cell suspension cultures under controlled environment and varying concentrations of different chemicals like calcium chloride, potassium, sucrose, manitol and naphthalene acetic acid (NAA) was studied. Increasing concentrations of calcium chloride, potassium, sucrose and sucrose plus mannitol were found to decrease the DFR activity, NAA also found to decrease the DFR activity at concentration of 1mg and 3mg but when NAA was increased up to 5mg concentration DFR activity was found to increase than the control.
The DFR, UFGT activity profile and anthocyanine content profile. Protein content, anthocyanin content and total DFR activity increases as berries mature. DFR activity is maximum in most of the samples treated with different chemicals at veraison stage while it decreases just before harvest. UFGT activity using quercetin substrate was found to decrease as berries mature.
22. Effect of nutrient imbalance on BSN in Thompson Seedless. A survey was conducted by research team on Maharashtra Rajya Draksha Bagaitdar Sangh, Pune. Affected samples were collected from different regions of Maharashtra and analyzed in laboratory. Rachis & pedicels were separated from samples, dried in oven at 600C for 8 hrs, and powdered for further analysis. Nitrogen content (3.97%) in affected rachis samples was much higher than unaffected samples (2.21%) also NH4-N of affected samples was higher than that of unaffected ones. Average potassium content (2.60%) was slightly higher than unaffected samples (2.05%). No significant difference was observed in the nutrients like P, Ca, K & Mg but K/ Ca + Mg ratio was higher in affected samples. High concentration of total nitrogen & NH4-N in pedicel & rachis cause BSN incidence in Thompson Seedless grapes.
23. Effectiveness of hydrogen cynamide (Sangh bud break 50% S.L.) in bud sprouting of Thompson Seedless grapes under western Maharashtra conditions. A multilocational trial of various concentrations of H2CN2 (SBB 50% SL) was conducted using Thompson Seedless on own rooted grape vineyards at Sangli, Solapur & Pune. Highest bud break (81.0%), lowest period for bud sprouting from initiation (3.20 days), the highest length of berry (19.71 mm), TSS (19.830 Brix) & yield (13.77 kg/vine ) i. e. 30.56 MT/ha was recorded by application of H2CN2 (Sangh Bud Break) at 3% followed by treatment with SBB at 2.5%
24. Exaluation of some insecticides against Pink Mealy Bugs & Thrips in grape ecosystem in Maharashtra. The experiment was carried out on Tas-A-Ganesh variety at MRDBS Manjri Farm, Pune. Two foliar applications of imidacloprid 17.8 SL (0.30 ml/L) & thianmethoxam 25 WG (0.25 g/L) reduced pink mealy bug and thrips population on grapevine & bunch with significant increase in fruit yield & no adverse effects on naturally occurring predatory stages viz, grubs & beetles.
25.Relative performance of Thompson Seedless grape grated on different root stocks. The trial was conducted at the Research farm of MRDBS, Pune on Thompson Seedless. Among the available root stocks the vines grafted on Bangalore Dogridge was found to be superior over salt creek and American Dogridge in terms of leaf area, berry diameter no of clusters per vine, Average weight of bunch & yield.