Fruiting indicators of the apple tree growing in the creeping form in the Botanical garden named after Vs. M. Krutovsky

Study of the fruiting indicators of the apple tree growing in the creeping form in the Botanical garden named after Vs. M. Krutovsky resulted in the distinguishing of the cultivars characterized by the high annual yield, apples mass and sizes. The distinguished cultivars can be recommended for growing in the given and similar climate conditions.


Introduction
Apple tree is a key fruit crop in Siberian gardens that occupies 65-75 % of the fruit plantings, and the 1 st in harvesting.
The quantity of the world grown cultivars varies from 25,000 to 35,000 in different ratings. There are nearly 350 apple tree cultivars appropriate to the geographical location on the territory of our country. Common Siberian assortment of apple trees can be divided into 3 different in genetic aspect groups of cultivarsrennets, semi-fruited (polukulturki), and large-fruited [2].
Apple tree fruits are consumed fresh and processed; they contain sugars, organic acids, mineral salts and microelements, they are endowed with biologically active substances as well. Apples contain vitamins and antioxidants [5]. They are also useful for humans because of fiber content [3].
Economic and biological properties of the fruit trees are determined not only by the genetic peculiarities of the apple tree species and cultivars, but also by the environment the phenotypes are formed in. Geographical factors (latitude, longitude, terrain of the region, etc.) significantly determine the zone climatic conditions influencing the fruiting, chemical content, keeping quality and other fruits properties [14]. Thus, from north-west to south-east within a country some cultivars increase their fruiting periodicity with the yield decreasing as a result [4].
The Botanical garden named after Vs. M. Krutovsky where the study was made in is located in Krasnoyarsk on the right bank of the Yenisey River in the estuary of the Laletina River. The garden territory is situated on the junction of the Kansk -Rybinskaya basin and foreststeppe zone of Western Siberian flatland with foothills of the Eastern Sayan. It causes the strongly continental climate conditions [1]. There was studied the memorial part of the garden the apple trees grow in a creeping form in. The form invented by Vs. M. Krutovsky in the beginning of 20 th century is called Arctic or Krasnoyarsk stanian. The Botanical garden apple trees collection has 39 largefruited cultivars of different geographical and selection origin [7,8,9,10]. The trees are maximum 115 years old.

Methods and materials
The fruiting periodicity was determined according to the common method [13] by annual calculation of the fertile trees. The yield estimation was done with method of model branches [11,12] including the calculation of the fruits only on model branches average for the given tree and simultaneous clockwise determination of such branches on the tree. Fruits mass was determined by weighing method on the laboratory scale.
The tree yield (in kilogrammes) was determined by multiplying of an average fruits mass on a tree by their quantity.
Processing of the experimental material was done by the mathematical statistics methods with the help of Microsoft Excel programme.

Results and discussion
Vs. M. Krutovsky initiated the creation of the collection of domestic apple tree cultivars (Malus domestica Borkh) in 1904. Apple tree cultivars are differentiated in fruits size, form and mass, their gustatory qualities, ripening period and storage time, fruiting periodicity.
According to the ripening period and storage time the apple tree cultivars of the memorial part of the Botanical garden named after Vs. M. Krutovsky can be classified into winter cultivars (64 %) and summer ones (36 %). 6 cultivars (White Transparent, Bismarck, Grushovka moskovskaya, Golden schip, Nobilis, Papirovka) constitute more than a half of the total amount of the apple trees (55 %).
Apple tree is prone to fruiting periodicity that develops with aging. Among the apple tree cultivars presented in the collection of the Botanical garden named after Vs. M. Krutovsky Grushovka moskovskaya shows the abrupt periodicity according to literary data [6].

Conclusion
As a result of the study there was established that all the apple trees of the Botanical garden named after Vs. M. Krutovsky have a high yield over the age of 100. There were selected the cultivars for growing in the given and similar natural and climatic conditions (White Transparent, Bismarck, Papirovka).