Information on the condition of vineyards of Ukraine on February 1, 2021 year
Published: 01.02.2021 y., 10:21 | Author: Кузьменко Артем
January in the wine-growing zone of Ukraine was characterized by unstable weather. The average monthly air temperatures were above the norm and were, in Uzhgorod, Odessa, about +1ºC of heat, Mykolayiv, Kherson about 0ºC, in Zaporizhia – -1ºC of frost. Against the general background of weakly positive and weakly negative air temperatures, a sharp decrease in temperature was observed at the end of the second decade. The minimum air temperatures dropped in Zaporizhia, Kherson, and Mykolayiv to 19-21ºС, and in Uzhhorod to 11ºС. In Odesa oblast, this indicator decreased in Odesa to -16ºС, in Izmail to -13ºС, in Bolgrad to -14ºС, in Saratov to -21ºС, in Belgorod-Dniester to -15ºС, in Rozdilna to -18ºС. Maximum air temperatures rose to 10-12ºС of heat. Precipitation during January was heavy and fell in the form of rain, snow and sleet. Their number was in Uzhgorod – 113 mm, in Odessa – 115 mm, in Nikolaev – 68 mm, Kherson – 72 mm, in Zaporozhye 80 mm.
The decrease in temperature in the second half of January somewhat worsened the situation with the preservation of grape buds in the vast majority of industrial plantations in southern Ukraine. Determination of the degree of damage to the buds in wintering buds as of January 22 showed that in many table varieties resistant to frost (Queen of Vineyards, Cardinal, Italy, etc.), the death of central buds in the buds reaches 90-100%, the cells of the main technical varieties are damaged by about 10-30%. A significant level of damage to both central and replacement buds was observed on low-frost-resistant technical variety of Merlot grapes.
Different nature and degree of damage to grape plantations, in such extremely unfavorable winter conditions, are mainly due to the placement of plantations without taking into account the quantitative indicators of the main agroecological factors, violations of agricultural techniques and frost resistance of varieties. Among the standard European varieties with high frost resistance are Rkatsiteli, Aligote, Cabernet Sauvignon (technical) and Delight (table). Varieties of the new selection Muscat Odesa, Zagrei, Aromatny (technical), Tair, Kometa and others were noted for their resistance to extreme conditions (dining room).
Determination of embryonic fertility of cells on different varieties of grapes showed that this year it is at or slightly above the average long-term values. It should be noted that due to the arid vegetation conditions of the previous year, the physiological condition of the bushes and the maturation of their growth were unsatisfactory. Therefore, on plantations that have been significantly affected by drought, pruning is carried out taking into account the strength of shoot growth, in some cases with the restoration of individual elements of the crown of the bush.
In order to reduce the negative effects of frost, restore plant growth and get the maximum possible yield, it is necessary to carefully determine the degree of damage to grapes in each area of a particular variety and pruning shrubs differently, taking into account their condition.
Data on the death of buds in the cells are taken into account when pruning shrubs. If the death of the central buds does not exceed 70%, then in this case you can get a normal harvest, increasing the load on the bushes buds. It is better to increase the load of such bushes at the expense of the strengthened fruit links, that is in each fruit link on fruiting it is necessary to leave not one, but two fruit arrows.
On bushes, where 70 to 90% of the central buds are damaged, the load is increased, leaving on the bushes all the normally developed shoots, which are cut by 8-12 buds. In order not to disrupt the accepted formation of the bush and create full-fledged fruit links for the next year, the bushes leave an additional number of 2-3 budding substitutes on the horns and perennial sleeves. The death of 90-100% of central and replacement buds almost excludes the potential for grape harvest in the current year. In areas of plantations with such a degree of damage, the main goal is to restore the crown of the bushes with the use in the growing season of techniques of accelerated formation, and so on. Pruning of all shoots of bushes with such degree of damages is carried out short, on 2-3 cells.
Warm winter weather and the absence of frosts had a positive effect on the storage of infectious diseases and pests in the vineyards, and due to the long autumn the stock of infection increased. As a result, the infectious background will increase in the spring, so growers should expect some problems during the season, so early fungicide treatment should be mandatory in the crop protection scheme. First of all, in the spring you should expect the intensity of the spread of black spot and anthracnose, these are the diseases that are one of the first to begin to develop and affect the grape plant. Among pests, first of all it is necessary to wait for intensive development of bud pests which start to wake up and damage plants already at a temperature from 5ºС. Therefore, if the treatment is carried out at low temperatures, it will be more appropriate to use drugs based on pyrethroids, as systemic insecticides are less effective in such conditions. However, warm winters also have negative factors for good overwintering of pests, such as grape leafhoppers and other insects, because under such conditions they are more affected by diseases. So the number of pests will decrease slightly, but currently the stock of viable wintering pupae of the pest is very large. Even with the possible onset of colds, the situation with diseases and pests will not change dramatically, so in the spring, in addition to the mandatory early spring treatment («washing») of bushes, to cope with a high load of diseases and pests, it will be necessary to carry out treatment in 2-3 leaves and during the period of extension and separation of inflorescences.