UDC 634.2
RESISTANCE OF CHERRY AND PLUM CULTIVARS FROM SECONDARY CISURALS MICRO SOURCE AREA TO THE ENVIRONMENT ABIOTIC FACTORS
Saprykina I.N., Post-graduate student Orenburg State Agrarian University, Orenburg, Russia E-mail: [email protected]
ABSTRACT
Different species of stone fruit crops for normal growth and development require different environmental conditions. Deep and complete study of the abiotic factors influence allows operating their development changing and creating certain conditions. The lowered air humidity is one of the reasons of bad and unstable fructification of varieties and forms of cherry and plum. During flowering it leads to a stigma and anther drying up and as a result a fruit drop. Drought resistance and heat resistance research, gives the chance of the correct purpose of servicing and agrotechnology that increases productivity.
KEYWORDS
Stone fruit crops; Cherry; Plum; Abiotic factors; Drought resistance; Heat resistance; Humidity; Cisurals; Temperature.
The cherry and plum crops peculiarity in Orenburg is fructification irregularity This phenomenon is provided with insufficient winter resistance of flower buds: frequent subfreezing in winter, after plants coming out of true dormancy state, or in early spring, and also flower buds damage during blossom, because of cold spell in spring.. But it is not the only reason. Water supply of these plants is of great importance [1]. Only at sufficient quantities of moister in the soil and air the mineral substance absorption, solution and transition of formed organic matter are done by a plant in ordinal order. All biochemical processes take place at water presence in a plant; water is necessary to build nucleus, plasma and other cell parts [2].
Cherry and plum are relatively drought resistant crops; they are inferior by this characteristic to almond, apricot, and peach. But the moisture deficiency at the beginning of the vegetation period, when the shoots growth rate is the most high and the water demand is great, leads to insufficient amount of growth. A set which is formed simultaneously with shoots growth shatters strongly or completely. Also, next year fruitage decreases. Air drought is the most dangerous. Even at enough amount of moisture in the soil air drought can result in drying out of shoots apexes, shrinking and fruit drops [3].
Hot resistance is a biological property of a plant to endure elevated temperatures that cause overheating. High temperature lasting effect can result in burn of bark, leaves and fruit; their external appearance, tastes get worse and simultaneously the amount of fruit droppage increases. The cases of complete plant death are registered. Stone fruit crops easily endure the positive temperatures transition beyond 50°C [4].
MATERIAL AND METHODS OF RESEARCH
Researches on heat resistance and drought resistance of different varieties were carried out on the basis of State Scientific Institution of "Orenburg Experimental Station of Horticulture and Viticulture”. The local cherry and plum cultivar collection appeared in the secondary Cisurals micro source area in the Orenburg territory is created [5].
The research objects at drought resistance determination are 6 introduced plum varieties Ruslan, Vega, Svetlana, Khabarovskaya Rannya, Antonina (from Primorskaya horticultural and berry-like station; Kuyashskaya (Scientific Rsearch Institute of Hoticulture and Potato growing, Chelyabinsk); 5 introduced varieties and forms of cherry:
Apukhtinskaya, Malinovka, Plamennaya, nT-2007, Bagryanaya (from Sverdlovsk horticulture breeding station).
The research objects at heat resistance determination are 5 plum varieties: Ruslan, Belosnezhka, Vega, Svetlana, Sharovaya; 3 varieties and forms of cherry Bagryanaya, Plamennaya, nT-2007. Drought resistance and heat resistance were determined in the hottest and dry weather period (III decade of July), when average daily temperature corresponded to +30....+32C. Sample selection was done in the morning time. Indicators of heat resistance and leaf water conditions were studied with the laboratory method according to methodical recommendations of M.D. Kushnerenko [4], P.A. Genkel [6].
Heat resistance of cherry and plum leaves was diagnosed with the artificial wilting method in 3-fold replication 5 leaves in every repetition. Leaves were selected in the middle of growth shoots. Leaves were labeled and put into a wet package and were brought to the laboratory where they were weighted and their leaf stalks were put into a flask with water. After complete saturation the leaf stalks were soaked up with filter paper and weighted. Then leaves in the process of wilting were weighted in 2, 4, 8, 12, 24 hours. After 24 hours leaves are put into a flask with water for 1 hour, for the repeated saturation. After this water content in leaves (CB), or watering (for wet and dry mass); water deficit (Bfl); saturation deficit (flH); relative turgor (OT); degree of turgor reduction (CBT); water loss at drying, or water-retaining capacity of leaves (BC) were determined. Average differential speed of water loss (CflCB) was defined with method of V.I. Avdeev (2005) [7,8].
At defining leaf water conditions the water content or their watering for dry mass was calculated. The water-retaining capacity indicator was presented with two parameters: by maximum water loss (Bn) for the moment (hour) of wilting process finishing and according to CflCB during the wilting process. The heat resistance indicators (according to Matskov) were calculated by the method of variety study of horticultural, berry-like and nut crops [9].
Samples from 5 leaves each were put into water bath at the temperatures from 45 to 75°C for 10 minutes. Then they were cooled and put for 10 minutes in 0,1H hydrochloric acid solution. Degree of sample resistance was judged by the degree of brown discoloring of leaf tissue (% from total area). Selection of temperature conditions for heat resistance assessment was done individually for cherry and plum crop.
RESULTS AND DISCUSSION
For the investigation moment there were unfavourable ecological conditions for cherry and plum cultivars. Average air humidity during the last decade of June was 47%, rainfall was on the average 24 mm, and at normal amount for the given period was 41 mm. This month had no more than 13 days, when air humidity was below 30 %.
The results of heat resistance investigation are given in Table 1. Water content for the moment of research (CB) on drought resistance was normal and corresponded on the average to 59,5% for plum - for wet mass, 148% - for dry mass; for cherry was 60,9% - for wet mass, 164% - for dry mass.
Water saturation deficit of plant cells appearing as a result of intensive water loss by a plant which is not refilled by its absorption from soil depends from particular environment conditions. In our case the water deficit indicators (Bfl) and saturation deficit (flH) were not high, because the leaves of the plans under consideration were collected in the morning hours. On the average plum water deficit was 8,7%, cherry - 9,2%. Saturation deficit was lower: plum - 5,4%, cherry - 5,9%.
The less water deficit of the investigated samples the higher relative turgescence indicator. Variation degree was not high: for plum was from 88,3% to 94,4%, but for cherry was a bit lower - from 82,6% to 89,9%. During the first two hours water losses were the most intensive. It is conditioned with the fact that water of saturation is incomparably richer in energy and thus kinetically more movable than cell water [7]. Then the rate decreased and was approximately equal during the next wilting hours.
Table 1 - Average indicators of leaves heat resistance of cherry and plum
variety/form Water content in leaves (СВ), % saturation deficit (ДН), % water deficit (ВД),% relative turgescence of leaves (ОТ), % degree of turgor reduction (СВТ), % maximum water loss at wilting (ВП), % average differential speed of water loss (CflCB), mg/g for 1 hour
for wet mass for dry mass
Plum
Ruslan 60,55 153,47 3,51 5,65 94,35 54,55 57,93 31,53
Kuyashskaya 59,11 144,76 6,56 10,61 89,73 68,32 57,55 48,09
Vega 55,52 126,49 6,77 11,75 88,26 72,76 56,95 41,39
Svetlana 57,67 135,43 5,46 8,96 90,91 62,98 57,57 50,35
Khabarovskaya eraly 61,21 157,84 4,93 7,81 92,18 61,38 60,33 42,01
Antonina 62,84 169,94 4,91 7,55 92,45 57,33 59,42 39,78
Cherry
Apukhtinskaya 56,71 167,51 3,84 5,99 82,55 78,56 41,38 24,93
Malinovka 60,96 156,31 7,46 11,68 88,32 72,1 45,98 26,92
Plamennaya 61,98 163,17 5,17 8,15 91,81 76,65 43,63 26,61
Пт-2007 62,51 167,4 6,56 10,09 89,91 71,76 44,56 26,93
Bagryanaya 62,45 165,95 6,57 10,13 89,87 79,34 40,39 24,04
The maximum indicators of maximum water loss (Bn) are for plum 60,3%, on the average CflCB equal to 42,0 mg/g for 1 hour; for cherry - 46,0%, CflCB - 26,9 mg/g for 1 hour.
After 24-hours wilting the repeated water saturation was carried out to determine the degree of turgor reduction (CBT), by which it is possible to judge about the degree of plants drought resistance, together with other indicators. The plum maximum turgor reduction was 72,8%, minimum - 54,6%. The cherry indicators were higher: maximum turgor reduction was
- 79,3%, minimum - 71,8%.
At continuous high temperatures normal physiological plant functions are suppressed, and at the temperature of about 50°C complete cell necrosis is possible (see table 2).
T able 2 - Heat resistance of cherry and plum according to degree of brown discoloring of leaves
(in % from total area)
variety/form temperature, ° С
45 47 50 52 55 57 60 62 65 67 70 75
Plum
Ruslan 0 0 0 1 75 85 100 - - - - -
Belosnezhka 0 0 0 0 40 50 90 100 - - - -
Sharovaya 0 0 0,5 2 40 85 95 100 - - - -
Vega 0 0 0 0 45 85 100 - - - - -
Svetlana 0 0 1 70 80 90 100 - - - - -
Cherry
Bagryanaya 0 0 0 0,5 1 45 90 95 100 - - -
Пт-2007 0 0 0 0 0 2 55 75 100 - - -
Plamennaya 0 0 0 0 0 25 30 45 60 80 95 100
It is obvious from Table 2 that critical temperature at which the plum leaves were not damaged is 50°С, and cherry - 55°С.
At the same time the minimum temperature when complete brown leaves discoloring takes place is 60°С, максимальная - 62°С. Cherry has the minimum temperature of 65°С, and maximum of 75°С.
CONCLUSIONS
Thus, the investigation results show that among plum samples the most drought resistant and heat resistant is Vega variety, Its maximum water loss is 57,0 %, and the СДСВ
indicator is 41,4%. Among cherry samples the most resistant to high temperature influence is
Apukhtinskaya variety, the maximum water loss is 41,4%, and CflCB -25,0%. The given
varieties differ in comparative drought resistance and possess the increased water-retaining
capacity, thus they are the carriers of valuable adaptive characteristics.
REFERENCES
1. Shishkanu, G. V. Plant metabolism ai drought and extreme temperatures / G. V. Shishkanu, M. D. Kushnirenko, A. F. Kirillov, T. Kh. Levit - Kishinyev: «Shtiintsa». 1983.
- 132 p.
2. Anzin B. N. Plum. / B. N. Anzin, Kh. K. Enikeev, M. I. Rozhkov - M.: State Publishing of Agricultural Literature. 1956. - 436 p.
3. Kolesnikov, A. F. Cherry. / Kolesnikov A. F., Kolesnikov A. I., V. G. Mukhanin - M.: Agropromizdat. 1986. - 236 p.
4. Kushnirenko, M. D. Methods of study water exchange and drought resistance of plants. / M. D. Kushnirenko, E. A. Goncharova, E. M. Bondar - Kishinyev, 1970. - 79 p.
5. Avdeev V. I. Apricots of Eurasia: evolution, genofund, introduction, selection. /V. I. Avdeev - Orenburg: Publishinf House of Orenburg State Agrarian University 2012. - 408 p.
6. Genkel, P. A. Physiology of plant heat resistance. / P. A. Genkel - M., 1982. - 280 p.
7. Comparative analysis of drought resistance of woody fruit plants species / V. I. Avdeev // Vestnik of Orenburg State Agrarian University. Ser. Natural sciences. - Orenburg, 2005. -№3. - P. 64 - 74.
8. Thermodynamics of drought resistance of woody fruit plants / Avdeev V. I., Avdeeva Z. A, Bykova E. A // Methodical support of steady development of modern horticulture: materials of international research and practice conference - Samokhvalovichy, Byelorussia, 2006. - T.18, part 2. - P. 125-129.
9. Program and method of variety study of horticultural, berry-like and nut crops. - Orel, 1999.- 426 p.