Genetic variation & Intercultural management in Grape

GENETIC VARIATION & INTERCULTURAL MANAGEMENT

OF GRAPEFSC-502

COLLEGE OF AGRICULTUREASSAM AGRICULTURAL UNIVERSITY, JORHAT

DEPARTMENT OF HORTICULTURE

Presented to:Dr. R.P. DasProfessor, Pomology

Presented By:Utpal Das14-AMJ-93

Genetic VariationGenetic variation refers to diversity in gene frequencies. Genetic variation can refer to differences between individuals or to differences between populations. Mutation is the ultimate source of genetic variation, but mechanisms such as sexual reproduction and genetic drift contribute to it as well.

Grape is grown under a variety of soil and climatic conditions in three distinct agro-climatic zones, namely,

Sub-tropical climatic regions , Hot tropical climatic regions and Mild tropical climatic regions in India.

Sub-tropical Region This region covers the northwestern plains corresponding to 28° and 32° N latitude including Delhi; Meerut district of Uttar Pradesh; Hissar and Jind districts of Haryana; and Bhatinda, Ferozpur, Gurdaspur and Ludhiana districts of Punjab.

Vines undergo dormancy and bud break starts in the first week of March while the rains arrive in the first week of June, and therefore, only 90-95 days are available from the initiation of growth to harvest.

Consequently, ‘Perlette’ is the only early ripening variety grown in this region.

Rain damage is a problem with Thompson Seedless in this region.

Single pruning and a single harvest is the accepted practice here.

Hot Tropical Region • This region covers Nashik, Solapur, Pune, Latur

districts of Maharashtra; Andhra Pradesh; Karnataka lying between 15° and 20° N latitude.

• This is the major viticulture region accounting for 70 percent of the area under grapes in the country.

• Vines do not undergo dormancy and double pruning and a single harvest is the general practice in this region.

• Maximum and minimum temperature is 42°C and 8°C, respectively.

• The major problems in this region are soil and water salinity and drought.

• Thompson Seedless and its clones (Tas-A-Ganesh, Sonaka), Anab-e-Shahi, Sharad Seedless and Flame Seedless are the varieties grown in this region.

Thompson Seedless

Mild Tropical Region An area covered by 10° and 15° N latitude including Bangalore and Kolar districts of Karnataka; Chittoor district of Andhra Pradesh and Coimbatore; and Madurai and Theni districts of Tamil Nadu fall in this region. Maximum temperatures in a year seldom exceed 36°C, while the minimum is about 12°C. Principal varieties are Bangalore Blue (Syn. Isabella), Anab-e-Shahi, Gulabi (Syn. Muscat Hamburg), and Bhokri. Thompson Seedless is grown only with limited success. Except for Thompson Seedless, two crops are harvested in a year. Vinifera varieties susceptible to mildew suffer losses due to unprecedented rains during flowering and fruit set in both hot and mild tropical regions.

Various speciesVitis vinifera, the European grapevine. Native to the Mediterranean and Central Asia.Vitis labrusca, the Fox grapevine, sometimes used for wine. Native to the Eastern United States and Canada.Vitis riparia, the Riverbank Grapevine, sometimes used for winemaking and for jam. Native to the entire Eastern U.S. and north toQuebec.Vitis aestivalis, the Summer Grape, native to the Eastern United States, especially the Southeastern United States.Vitis rotundifolia (syn. Muscadinia rotundifolia), the Muscadine, used for jams and wine. Native to the Southeastern United States fromDelaware to the Gulf of Mexico.Vitis rupestris, the Rock grapevine, used for breeding of Phylloxera resistant rootstock. Native to the Southern United States.Vitis amurensis, native to the Asian continent, including parts of Siberia and China.Vitis vulpina, the Frost Grape, native to the Eastern United States.

Variation occurs due to:-

1. Hybridization:-As grape vine is a heterozygous & loss of vigour & fertility occurs due to in breeding. To overcome this crossing of unrelated parents with good combining ability is done & hybrids with desirable characters are selected from resulted seedlings.

Eg.- Arka Hans-BB x Anab-e-shahi, seeded berries of yellowish green color.

Arka Neelmani:- BC x TS, No pruning required & tolerant to anthracnose.

2.polyploidy:-Commercial grapes mostly belong to Euvitis section comprising of V. vinifera, V. labrusca, V. riparia and V. rupestris with the haploid chromosome number 19. In the other section, Muscadinia, the haploid chromosome number is 20. The cultivated grapevine (V. vinifera) is diploid.

3.Mutation:- natural & induced mutation are important sources of variations in grape sporting or mutation is interpreted as a result of change in a gene in an initial cell of the organ in which it appears.

Intercultural management of grape

Irrigation is given at 10 days intervalWater needs of vineyard are influenced by the following factors:-1.Age & condition of the vine. Young vines required more frequent irrigation than grown up vine.2. Soil type & climatic factors (temperature, RH, wind)3. Irrigation after pruning is necessary, as irrigation is seldom applied during winter when the vines remains dormant.4.The period between fruit set and maturity is the most critical as it requires adequate water during this period.

Irrigation

Intercrops are generally not recommended.

But now-a-days intercropping with radish, cucurbits, okra, brinjal, potato are done for first 2-3 years after planting of vineyards.

Cover crops of leguminous types like guara, cowpea are better to be grown and burry them at their maximum vegetative growth to improve soil quality.

Intercropping

FYM- for 1 year old grape vine is 20kg, 5 years & above 80 kg per ha.

For production of 1 tonnes of yield nutrient required by grapes is 8.0 kg N & 2.0kg P, 9.0 kg K.FYM N P K States

300 750 640 1000 Andhra Pradesh50 400 640 480 Himachal Pradesh70 400 105 100 Jammu & Kashmir25 270 450 900 Karnataka25 200 120 180 Maharashtra80 500 720 480 Punjab

Manures and Fertilizers

In case of twice pruning, 60% of annual dose of N, 50% P2O5 at April pruning and rest of N, P2O5 & entire K2O at October pruning is recommended.

Application of nutrient through foliage increase the efficiency of applied nutrients.

Application of 0.02% Mg, 0.2% Fe, & 0.4% B, result in better quality higher yield.

Fertigation through drip irrigation system is ideal which saves 30% of fertilizers quantity.

Time of fertilizer application

Problematic weeds like Cyanodon dactylon and Cyperus rotundus are removed manually by digging deep to remove their deep-seated runners.Mulching is commonly practiced to check weed. Pre-emergence application of Diuron, Simazine or Atrazine @ 2 kg a.i. /ha and Goal (Oxyfluorfen) @ 1 kg a.i. /ha after pruning is recommended.Glyphosate @ 10 ml/litre mixed with 5g of Ammonium Sulphate and detergent, as a post-emergence spray is effective in controlling weeds.

Weed Control

A. Kniffin systemB. Head systemC. Telephone or overhead trellis systemD. Bower system

Training methods for grape

The main objective of pruning of grapevines is to facilitate intercultural operations, and maintain desired vine shape and vitality for constant and increased productivity.In Maharashtra, north Karnataka and Andhra Pradesh the vines are forced to undergo rest for about a month immediately after harvest to store food material in the mature parts of the vine. The canes are cut back in April by keeping 1-2 buds which develops into canes in 4-5 months. The dried canes are also removed. Here it is called 'back pruning' or 'growth' pruning. In the month of September-October these canes are pruned for fruiting. This pruning is called 'forward pruning' or ‘winter pruning’. In Tamil Nadu pruning is done during November-December for summer crop harvested during March- April. While pruning in May-June results in second crop during August-September

Pruning

Spur pruning Cane pruning Mechanical pruning

Dormant pruning Summer pruning

Pruning methods

Type of pruning

The removal of flower clusters before flowering or parts of such clusters after fruit set is called thinning.

Types of thinning methods 1. Flower cluster thinning .2. Flower thinning 3. Cluster thinning 4. Berry thinning

Thinning of fruits

Flower cluster thinning

Cluster thinning

Shoot pinching is done when the main shoot attains 7-8 leaf stage.During pinching the tip of the mature shoot is pinched by retaining only five nodes.As a result the terminal bud along with 1-2 laterals resumes growth. These laterals are called as sub-canes.Buds up to third node from the base on the sub-cane were found to be invariably fruitful resulting in 2-3 clusters/cane

Shoot Pinching

Girdling is removing a narrow ring of 4-5 mm width of bark entirely around some member of vine like arm or cane.

It is done to improve fruit set increase berry size & advance maturation.

Girdling

GrowthRegulators

Concentrations

Time of Application Effects

NAA 20 ppm

15-20 ppm

20-25 ppm

Spraying at berry formation stage.Dipping bunches at sugarformation stageSpraying 10-15 days before harvest

Controls flower & berry dropImproves berry lustrePrevents berry dropin transit

IBA 1000-1500 ppm

Dipping of cuttings Promotes rooting of cuttings

4 CPA 10 ppm 1st spraying when the berrysize is 3 mm dia.2nd spraying when the berrysize is 6 mm dia.

Increases the pedicelthickness

Growth Regulators