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B. Plant–fungal interactions

B.2. Plant pathogenic fungi

B.2.2. Botrytis cinerea

After 1 e4 c5 2 'Llt3 'Llc6 3 d4 cxd4 4 'Llxd4 'ffb6 some moves not yet analysed come into consideration:

A: 5 .ie3 B: 5 lllb5

Editor's Note: 5 'Llxc6 is rarely seen. Hector-Grivas, Katerini 1992, continued 5 ... bxc6 6 .i.d3 e5 7 0-0 lllf6 8 llld2 .i.e7 9 lllc4 'fllc7 10 f4 d6 1 1 fxe5 dxe5 1 2 'fllf3 0-0 1 3 'fl!g3 l:te8 14 '>Ph 1 llld7 oo .

A:

5 .i.e3 (D)

B

An aggressive idea that has been seldom exploited in practice. Com­

pared to other variations of the Sicil­

ian Defence, where White obtains a dangerous initiative by sacrificing the b2 pawn (as for instance the Najdorf Poisoned Pawn Variation), here we have a case where the benefits are quite unclear. The sacrifice can be assessed as "semi-correct".

5 1rxb2

Black doesn't have any alternative.

6 'Llxc6

The alternative 6 'Llb3 was tested in the game Vitolins-Zaichik, Mos­

cow 1 983, where White obtained enough compensation for a pawn but it still feels as if Black could have played better. There followed 6 ... 'flle5 7 lLl 1 d2 lLlf6 8 f4 •c3 9 .i.d3 d5 10 e5 lllg4 11 .i.cS h5 1 2 0-0 e6 13 .i.xf8 Wxf8 1 4 'it'e1 t!fb4 (Better is 14 ... lllb4) 15 c4 dxc4 1 6 lllxc4 'fixe1 17 l:.fxel . Maybe the modest 8 ... 'ffc7 is a better choice because the white

knights don't have access to the d5 and b5 squares.

6 bxc6

It's logical that anybody who plays this line as White must be prepared to answer 6 ... ffxal. Unfortunately that position hasn't been tested in practice. A possible line is 7 .td4 'i!Yxa2 8 lt:\c3 '\We6 (8 ... 'ifa3? 9 lt:\b5) 9 lt:\xa7 with the idea lt:\d5 or lt:\b5.

6 ... dxc6!? is also possible.

7 �d2 d6

8 .x::lbt 'i!'fc3 This position arose in the game Van der Wiel-Kouatly, Cannes 1990, where the opponents agreed a draw after 9 R.d3 lt:\f6 1 0 0-0 ti'a5 1 1 lt:\c4 'flc1 1 2 f4 e5 1 3 \'We 1 Ae6 14 lt:\a5 exf4 1 5 �xf4 lt:\d7 1 6 .l:tb7 'iVc8 1 7

�a6 !il..e7 18 'iVe2 0-0 19 .l:txa7.

B:

5 �b5 (D)

This, the main alternative to 5 lt:\b3, is slowly starting to enjoy a respectable theoretical status. Black has to choose between:

B 1 : 5 ... a6 and B2: 5 ... lt:\f6.

Bl:

5 a6

6 .i.e3

White achieves less with 6 �5c3 e6 7 �d3, for example:

a) 7 ... 'flc7 8 0-0 b5 9 a3 lLlf6 1 0

�g5 $.e7 1 1 lt:\d2 l:b8 1 2 'ire2 d6 1 3 f4 h6 oo Danilovic-B.Knezevic, Budva 1 996.

b) 7 ... �f6 8 0-0 ii.e7 9 lt:\d2 0-0 1 0 �h1 d5 1 1 exd5 exd5 1 2 lt:\b3 .l:td8 13 �f4 !il..g4= Dvoirys-Lastin, Russia Cup semifinal, Perm 1997.

After 6 �e3 Black has the options:

B 1 1 : 6 ... 'li'a5+ and B12: 6 ... 'ifd8!.

Bl l :

6 Vas+

An enterprising but dubious con­

tinuation. The exposed queen will help White to accelerate his devel­

opment.

7 �5c3 e6

Or 7 . . . �f6 8 lt:\d2 b5 9 lt:\b3 'filc7 1 0 �e2 e6 1 1 a3 ..tb7 1 2 0-0 d6 1 3 f4 $.e7 1 4 !il..f3 0-0 oo Sanchez­

Schreiber, Zaragoza 1 994.

8 �d2

a) 8 .i.d3 b5 9 lt:\d2 Wlc7 (9 ... �b4 Or:

1 0 a4! �xc3 1 1 axb5! ..txd2+ 12

�xd2 ± Yudasin) 1 0 0-0 lLlf6 1 1 f4 b4? (1 L.d6 � ) 1 2 lt:\a4 l:tb8 1 3 '*i¥e2!

'f/a5?! (Better is 1 3 ... a5) 14 lt:\c4 'ifxa4 1 5 b3 'ifb5 1 6 lt:\d6+ and Black doesn't have enough

compen-sation for the queen, Yudasin­

J.Polgar, Madrid 1 992.

b) 8 .i.e2 b5 9 lUd2 lUf6 1 0 0-0 '¥iic7 1 1 f4 d6 1 2 il.f3 .i..e7 1 3 a4 b4 1 4 lUe2 l:.b8 1 5 lUb3 e5 1 6 a5 0-0 1 7 f5 �- � I. Almasi-Csom, Zalakaros 1 995.

8 b5

Others:

a) 8 ... Jlb4 9 lUc4 �xc3+ 1 0 bxc3 't!Vxc3+ 1 1 il.d2 'ii'd4 1 2 c3! is also favourable for White (Donchev-Teo Kok Siong, Thessaloniki OL 1988).

b) But 8 ... ffc7 is interesting: 9 lUc4 b5 10 lUb6 l:tb8 1 1 lUxc8 l:[xc8 1 2 a4 b4 1 3 lUb1 l:.a8 1 4 lUd2 lUf6 1 5 f4 d5 1 6 e5 lUxe5 (0- 1 in 3 1 moves) Lugo-A.Annas, Cuba 1 988.

9 a4 b4

10 �c4 'ffc7

11 �d5! (D)

This knight sacrifice is the best way to utilise the opening advantage.

Less enterprising is 11 'Llbl a5 12 lUb6 l:tb8 1 3 lUxc8 l:.xc8 14 lUd2 lUf6 1 5 �a6 l:ta8 1 6 �b5 �e7 1 7 0-0 0-0 18 f4 d5 1 9 e5 lUd7 20 lUb3 and now in the game Arnason­

Avshalumov, Belgrade 1988, Black

could have equalised after 20 ... f6 21

�xc6 't!Vxc6 22 exf6 il.xf6.

Following the excellent 1 1 �d5!, Black's position soon collapsed in the game Ehlvest-Smirin, Moscow 1 992, after 1 l ...exd5 12 exd5 lUd8 (12 ...

lUes 1 3 d6 ± ) 1 3 'i¥e2! d6 14 �b6+

'fie? 1 5 lUxd6+ 'it>d7 1 6 lUe4! (With the idea 1 7 'Wb5+! axb5 1 8 i..b5+

mate) 16 ... i..b7 1 7 0-0-0 f5 1 8 lUc5+

�e8 19 d6! 'irxe2 20 �xe2 lUf6 2 1 ..txd8 �xg2 2 2 �xf6 ..txh 1 23 ..th5+ g6 24 �xh8 1 -0.

B12:

6 'C'fd8!

7 �5c3 Others:

a) Interesting and original play was seen in the game I.Gurevich-J.

Polgar, New York 1 992, where there followed: 7 �5a3 b5 8 c4 b4 9 lUc2 lUf6 1 0 lUd2 il.b7 1 1 f4 d6 1 2 'ifn g6 1 3 0-0-0 �g7 14 e5 dxe5 1 5 fxe5 CLJd7 16 e6 fxe6 with a complicated game.

b) The second alternative is 7

�d4. Now, depending on Black's reaction, different types of Sicilian position can arise. The most ener­

getic, quick reaction in the centre with 7 ... e5 gave Black a solid play in two games following 8 CLJf3 lUf6:

b1) 9 �c3 �b4 10 il.c4 0-0 1 1 'li'd.3 d5!? ( 1 1 ... i..xc3+!? 12 bxc3 d6) 1 2 i..xd5 CLJxd5 1 3 'fixd5 �xc3+ 14 bxc3 i..e6 1 5 �xd8 lHxd8 1 6 0-0 l:lac8 �-�, Micic-Z.Ilic, Novi Becej 1 994.

b2) 9 .i.c4 'fia5+ 1 0 lUbd2 CLJxe4

1 1 0-0 lLlxd2 1 2 .i.xd2 'it'c5 13 'it'e2 iL.e7 14 b4 lLlxb4 1 5 lLlxe5 0-0 16 iL.xb4 'it'xb4 1 7 'W'h5 d5 1 8 iL.xd5

\11- Yz Svicevic-P.Kovacevic, Tivat 1995.

w

7 e6 (D)

This position was tested in several games:

a) 8 .i.e2 lLJf6 (8 ... b5 9 f4 iL.b7 10 0-0 iL.e7 1 1 J.D d6 1 2 lLld2 l0f6 1 3 'it'e1 0-0 14 'ii'g3 'ith8 oo Hendriks-Z.Ilic, Sas van Gent

1 994) 9 f4? ! (Carelessly played:

Black's position has a strong hid­

den possibility) 9 ... d5 ! 10 e5 lLld7 1 1 .to g5! + 1 2 fxg5 lLldxe5 1 3 iLxd5 exd5 1 4 lLJxd5 iL.g4 ! - + Rogers-Karpman, Belgrade 1 988.

White should have been satisfied with the solid 9 0-0.

b) 8 g3 lLlf6 9 iLg2 iLb4 1 0 0-0 0-0 1 1 f4 d6 1 2 'ithl .l:te8 1 3 .i.gl d5 14 e5 lLld7 1 5 llle2 iL.c5 with an unclear game, A.Rodriguez-Alvarez, Colon 1993.

c) 8 �a4!? b5 9 lLlb6 .l:tb8 1 0 lLJxc8 'it'xc8! (With the idea . . . lZJ f6,

... d5) 1 1 .i.f4 e5! 12 iL.e3 lLlf6 1 3 iL.d3 d5 1 4 exd5 lLlxd5 1 5 0-0 lLlxe3 16 fxe3 with a playable position for both sides, Kaidanov-Yermolinsky, Asheville 1 992.

B2:

s �f6

The postponement of the unavoid­

able ... a6 move is only temporary.

After this move the main line is dif­

ficult to determine.

6 �lc3

There are several unexplored pos­

sibilities.

a) 6 �Sc3 e6 7 iL.e2 J.e7 8 0-0 0-0 (8 ... a6) 9 lLld2 d5 10 exd5 exd5 1 1 lLlb3 d4 ( l l ...iL.e6 is more solid) 1 2 lLlb5 l:ld8 1 3 a4 l:ld7 14 a5 'tWd8 15 l:a4 ;!; Rantanen-Akopian, Palma de Mallorca 1989.

c) 6 .i.e3 'it'd8 (Weaker is 6 ...

'it'a5+ 7 'ii'd2 'it'xd2+ 8 lLJxd2 'itd8 with a considerable developmental advantage for White) when:

c I ) The variation 7 �d2 a6 8 lLlc4 axb5 9 ..tb6 bxc4 10 iL.xd8 c;Pxd8 1 1 iL.xc4 lLlxe4 12 .i.xf7 e6 1 3 iLxe6 iL.c5 Yeo-Mendez, Havana 1 994, leads to great complications.

c2) 7 �lc3 a6 (7 ... d6?! 8 lLld5) and now:

c21) 8 �d4 e5 when:

c21 1) 9 �xc6 bxc6 10 J.c4 iL.b4 1 1 'it'd3 0-0 1 2 .l:td1 'it'e7 1 3 iL.g5 h6 14 .i.xf6 'it'xf6= Paramos-Kurajica, La Corufia 1995.

c21 2) 9 �fS d5!.

c213) 9 �b3 .i.b4 10 ..tc4 b5 1 1 iL.d5 lLJxd5 1 2 'ii'xd5 0-0 1 3 0-0 'Wic7

14 l:.ad1 d6 15 'tlt'd3 ti:Je7 with good play for Black, L.Papp-Z.Papp, Szeged 1998.

c22) 8 �a3 b5 (8 ... e6? 9 ti:Jc4) 9 ti:Jd5 :Z.b8 10 ti:Jxf6 gxf6 1 1 �d3 e6 12 0-0 (If 12 f4, then Black plays 1 2 ... 'tlt'a5+! 1 3 ._,d2 Wxd2+ with equality; if instead 1 3 �d2 ._,b6 � ) 1 2 .. . ti:Je5! 1 3 Ji.e2 Ab7 1 4 f4 ti:Jg6 1 5 Ji.d3 l:tg8 16 l:tf2 l:tc8! and Black had active play for his pieces, Kotronias-Z.IIic, Lenk 1 990.

6 a6

7 �a3

Or 7 Ae3 Wa5 8 ti:Ja3 b5 9 Ad3 e6 1 0 ti:Jb1 b4 1 1 ti:Je2 d5 1 2 ti:Jd2 Ab7 Yz-Yz Howeii-Voka�, Lazne Bohdane� 1995.

w

7 e6 (D)

This way of playing for White cer­

tainly doesn't promise him any

ad-vantage. In all the games where the diagram position arose, Black was more successful than his opponent:

a) 8 g3?! is an unreasonable con­

tinuation in this particular position.

In the game Shabalov-Anastasian, Podolsk 1990, White was clearly in­

ferior after 8 ... Axa3 9 bxa3 ._,c5 10 Ab2 b5 11 Ji.g2 Ji.b7 12 l:lb1 ti:Ja5 1 3 0-0 e5 14 �h1 0-0 1 5 'tlt'd3 l:.ac8 1 6 h3 l:fe8 17 f4 ti:Jc4 =F .

b) 8 �c4!? is playable but insuf­

ficient to obtain the advantage. After 8 ... ..-c7 9 Ae3 b5 1 0 ti:Jb6 .l:.b8 1 1 ti:Jxc8 White had played seven moves with his knight in order to exchange it for Black's undeveloped piece.

Now in the game Amold-IIlner, Karlsruhe 1997, after 1 l ...l:.xc8 12 a3 ..ktd6!? White played badly with 1 3 Ji.xb5? and lost in a few moves after 1 3 ... axb5 14 ti:Jxb5 'iVa5+ 1 5 c3 'fi'xb5 16 ._,xd6 ti:Jxe4 17 'tlt'f4 'tlt'xb2 1 8 0-0 ti:Jxc3 etc.

c) Finally let's mention the game Zhelyandinov-Gufeld, USSR 197 1 , where White was also outplayed af­

ter 8 J\.d3 ._,c7! (Black has already equalised) 1 1 ti:Jc4 b5 10 ti:Je3 Ji.b7 1 1 0-0 �e7 1 2 f4 d6 1 3 1fe 1 0-0 1 4 a4? ( 1 4 b3 oo ) 1 4 .. . ti:Jd4! 1 5 e5 dxe5 16 fxe5 'tlt'xe5! 1 7 ti:Jf5 -'.c5 ! with a decisive advantage for Black.

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