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Influence of insects-phytophags on biogroups and ordinary plantings

Insects phytophags are the important biotic factor which is necessary for considering at studying of wood communities. On formation of the future young planting the greatest negative influence renders pine podkornyj a bug.

Pine podkornyj a bug (Aradus cinnamomeus Panz.) The-eurysynusic and hazardous pest of a forest in the European part of Russia, in Siberia and in the Far East. It damages mainly a pine ordinary, in bolshej degrees young growths (Valenta, 1975). On M.D.Danilov and A.A.Krasnov's (1970) researches, pine podkornyj the bug along with vysasyvaniem juice from tree living tissues allocates toxic substances which negatively affect growth of pines. Pine podkornyj the bug damages trunks of trees, exhausting contents of cages of living tissues. In places vysasyvanija it is formed ranevaja parenhima, interrupting water spending ways and interfering water delivery of roots in a crone. In an initial stage of damage on a wood surface under a bark there are silver-white stains which gradually turn yellow, and then burejut. Under a bark the cavities filled with resin are formed various magnitude. Further a bark rastreskivaetsja, forming smolotochashchie cankers. The gain falls, runaways are shortened, the top often dries out. The greatest harm pine podkornyj puts a bug to the cultures growing in steppe and forest-steppe zones. In a wood zone it meets in nizkopolnotnyh pine forests on poor and dry soils and in seed plantations of a pine where distances between trees are increased (Maslov, 1998, Harchenko, 1986).

On the basis of researches of last years following conclusions (Danilov, Krasnov, 1970) have been drawn: pine podkornyj the bug concerns photophilous kinds. In the pine forests which density reaches 0,5—0,6, settling by bugs of trunks varies and is defined by the location of trees. Most densely (43 pieces / sq.) are occupied the pines growing to the south. In process of advancement deep into forests the density of settlement of bugs on trees gradually decreases and on distance of 20 m are made only by 3 individuals / sq. dm.

Data on inspection of trees of biogroups on contamination pine podkornym are resulted by a bug in table 21. Within each age group it has been surveyed on 30 trees separately in biogroups and in rjadkah. The quantity podkornyh the bugs, having on the average on one trunk of biogroups, characterises phytocenose considered by us as poorly infected (tab. 21). The Maximum quantity podkornyh bugs on one trunk meets at the age of 21 years (11114, 11115), then the given indicator decreases. The minimum quantity of these insects - of phytophags meets on the trial areas at the age of 6 years. From age in 39 years infected podkornym trees of a pine ordinary are not revealed by a bug.

In biogroups of a pine ordinary (6 years - 24 years) podkornyj the bug meets more often mainly in marginal numbers (more than 90 %). The given fact speaks bolshej degree of light exposure of trees of marginal numbers (Harchenko, 1986).

Comparison of data on number pine podkornogo a bug in biogroups and numbers, shows, that trees of biogroups are infected by the given pest to a lesser degree (tab. 21).

Thus, at reafforestation by biogroups formed planting will be more stable against influence of such insects - of phytophags, as podkornye bugs.

Table 21.
The account pine podkornogo a bug on software
№ SOFTWARE Quantity

The considered

Trees,

Piece

Age,

Years

Quantity podkornyh bugs in biogroups, piece Including Quantity podkornogo a bug in biogroups, piece/1 a trunk Quantity podkornogo a bug in numbers, piece/1 a trunk
In

The central numbers, piece

In

The marginal

Numbers,

Piece

1 30 6 210 30 180 7 12
2 30 6 180 10 160 6 12
3 30 15 300 40 260 10 37
4 30 21 450 30 420 15 45
5 30 21 435 32 403 15 45
6 30 24 408 38 370 14 24
7 30 39
8 30 41 podkornyj the bug is not revealed
9 30 46



Also in the conditions of research area there are also other kinds of insects of phytophags. Considerable harm to wood cultures of a pine also put pobegovjuny and red pine pililshchik.

To pobegovjunam carry butterflies of family Listovertki (Tortricidae) which caterpillars are the pests damaging kidneys and runaways of various pines. In the conditions of Tsninsky forest area meets pobegovjun summer (Rhyacionia duplana) (рис35 is more often.).

Fig. 35. Damage young sosenok caterpillars summer pobegovjuna

(A photo of the author, 2012)


Red pine pililshchik (Neodiprion sertifer Geoff.) damages mainly trees of a pine ordinary (fig. 40). Special harm is put by caterpillars as they eat needles to the basis (It is blue, 2008). Flashes of mass reproduction red pine pililshchika arise in the presence of conditions favorable for it: warm and dry weather in the spring - in the beginning of summer within several years on end, presence of pure pine plantings, trees with the lowered protective reactions, an adverse environment of growth of forest stands and so on.

Therefore population of pine forests red pine pililshchikom can quite serve as the indicator of their stability (Vishnjakova, 2010).

Fig. 36. Red pine pililshchik: appearance, jajtsekladka, cocoons


According to the Tambov forest administration in territory of the Tsninsky forest area for last 7 years flashes of mass reproduction of insects-phytophags are not fixed.

By data lesopatologicheskogo monitoring FBU TSZL «Ryazan area» in territory of the Tsninsky forest area there are only centres of illnesses forests (table 22).

Table 22. Presence of the centres of illnesses of a pine ordinary in territory of the Tsninsky forest area from 2007 on 2013 gg
Presence of the centres of illnesses of a forest, hectares 2007

2008

2008

2009

2009

2010

2010

2011

2011

2012

2012

2013

(On 01.11.2013

Root sponge 164 164 127 105 87 77
False aspen tinder fungus 9 9 9 9 9 9
Pitch cancer 17 0 0 0 0 0
IN TOTAL 190 173 136 114 96 86


As of November, 1st, 2013 there was a reduction of the area of the forests amazed with a root sponge (tab. 22). And the centres of a root sponge are fixed in wood cultures of a pine ordinary, created rjadkami. In infection biogroups it is not revealed, that Infection of trees with a pitch cancer is very important against the mass centres of defeat by the given illness in the Central Chernozem region it was marked in 2007/2008. The area of the centres of infection with a false aspen tinder fungus with 2007 on 2013 gg did not change and makes 9 hectare.

Thus, biogroups of a pine ordinary are stable against various diseases of a forest, in particular to a root sponge that has very much great value.

3.5.

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A source: Semyonov Michael Aleksandrovich . Ecological mechanisms for the formation of ecosystem biodiversity in artificial reforestation (on the example of the Tsninsky forest area). 2014

More on topic Influence of insects-phytophags on biogroups and ordinary plantings:

  1. Influence of biotic factors on formation of biogroups
  2. Chapter 4. Mathematical modelling of processes of a course of growth in biogroups
  3. Structure of biogroups and competitive mechanisms
  4. Indicators of grow power of trees of biogroups
  5. Chapter 5. Methodical recommendations at creation of wood cultures by biogroups
  6. Physalis alkekengi L. - Fizalis ordinary
  7. Ekologo-biological features of a pine ordinary (Pinus sylvestris L.)
  8. Armoracia rusticana Gaertn., Mey. et Scherb. - the Horse-radish ordinary
  9. Chapter 3. Features of the wood phytocenoses created by a method of biogroups
  10. the Appendix Distribution of trees of biogroups on classes of growth of Kraft
  11. Ligustrum vulgare L. - the Privet ordinary