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Effect of different organic manures on the efficiency of VA mycorrhiza
55
Agriculture, Ecosystems and E~vironment, 29 (1989) 55-58 Elsevier Science Publishers B.V., Amsterdam Printed in Czechoslovakia
E f f e c t of d i f f e r e n t
o r g a n i c manures on t h e e f f i c i e n c y o f VA mycorrhiza
Andrea B r e c h e l t I n s t i t u t ftlr Pflanzenbau und T i e r h y g i e n e i n den Tropen und Subtropen d e r G e o r g - A u g u e t - U n i v e r s i t ~ t G 0 t t i n g e n , G r i s e b a o h s t r . 6 , D-~400 G~ttingen A_bstract The i n f l u e n c e o f s t e r i l i z e d and u n s t e r i l i z e d s t a b l e manure and two d i f f e r e n t k i n d s of compost on t h e e f f i c i e n c y of VA m y c o r r h i z a l n ~ . ~ aioum annuum was examined. The magnitude of t h e p o s i t i v e e f E e o t o f VA mycorrhlza on p l a n t y i e l d d e c r e a s e d w i t h i n c r e a s i n g amounts o f o r g a n i c manure due t o b e t t e r growth of the n o n m y c o r r h i z a l p l a n t s . Co,spared with t h e s t e r i l e t r e a t m e n t s , the m y c c r r h i z a l e f f e c t was b e t t e r with u n s t e r l l e manures when t h e p o s s i b l e n u t r i e n t s o u r c e s provided by t h e manures were low. Introduction I t has p r e v i o u s l y been shown t h a t t h e e f f i c i e n c y of VA m y c o r r h i z a on p l a n t y i e l d always decreased with i n c r e a s e d amounts of f r e s h o r g a n i c manures (BRECHELT 1987). The r a t e o f t h i s r e d u c t i o n was n o t dependent only on t h e n u t r i e n t c o n t e n t s of t h e manures. In ol'der examine the r o l e of the n u t r i e n t s and the r e a s o n s f o r d i f f e r e n t i n f l u e n c e s of o r g a n i c manures, u n s t e r i l e m a t e r i a l was compared with t h e e f f e c t of t h e c o r r e s ponding amounts of the same manures in a s t e r i l e and ho~,Loseneous form. M a t e r i a l and Ne~hods The VA m y c o r r h i z a l funsu~ Acaulos~ora l o n g u l a (SIEVERDING p e r s . i n f o r mation) was grown on Capsicum annuu~ i n a poor f o r e s t s o i l as d e s c r i b e d by BRECHELT (1988). To compare t h e i n f l u e n c e of s t a b l e manure, compost from s t a b l e manure and compost based on p l a n t remains ( v a l i a n t I) w i t h t h e i r c o r r e s p o n d i n g amounts in a s t e r i l e form ( v a r i a n t I I ) , the manures were s t e r i l i z e d ~20aC f o r 8 h o u r s ) and ground b e f o r e a p ~ l i c a t i o n , t h e manures were added a t 4 c o n c e n t r a t i o n s r ~ 0 , 100, 200, ~00 d r / h a . T h e i r phosphorus c o n t e n t i s given in t a b l ~ 1t f o r a l l t h e o ! h e r n u t r i e n t s and l n f o r m a t i o n s eee
BRECHELT (1988). Inoculation of the experlmental plants with AcaulosDora lon~ula took p l a c e a t t r a n s p l a n t a t i n g i n t o 1 k g - p o t s usin~ i n f e c t e d p l a n t r o o t s o f Eupatorium odoratum.
Results and Dieousslon As r e c e n t l y shown (BRECHELT 1987), i n c r e a s e d amounts o f f r e s h o r g an i c m a t e r i a l ( I ) l e d t o a decrease i n myoorrhiza e f f i c i e n c y ( t a b . 2 ) .
The
56
increasing n u t r i e n t concentrations of the s o i l in treatments with higher amounts o f o r g a n i c manures caused t h i s r e d u c t i o n (SCH~BECK 1980). Higher amounts of t h e d i f f e r e n t t y p e s o f manures reduced d i f f e r e n c e s between t h e i n o c u l a t e d (M) and non i n o c u l a t e d (NM) p l a n t s more o r l e a s q u i c k l y dependin~ on t h e s t a g e o f m a t u r i t y and t h e kind o f s t a r t i n g m a t e r i a l . The r e s u l t s were l i t t l e i n f l u e n c e d by t h e a v a i l a b i l i t y o f n u t r i e n t s ( t a b . l ) dur i n g th e time o f a p p l i c a t i o n . The a c t i v i t y o f s o i l 1microorganisms Drobably improved t h e a v a i l a b i l i t y o f t h e n u t r i e n t s d u r i n g t h e v e g e t a t i o n p e r i o d . This p r o c e s s can v a r y in i n t e n s i t y d ecen d i n g on t h e o r g a n i c t r e a t m e n t (BRECHELT 1987). M i c r o b i a l a c t i v i t y can a l s o f i x n u t r i e n t s (J~GGI 1974),
produce antibiotic substances (BEINE~T and SAUERLANDT 1951), enzymes (J~GGI 19~4), organic acids and influence other microorganisms (MAI~AWI 1982, MIS~RA and TA~HO 198~), any o f which could a f f e c t
the efficiency
o f the VA m y c o r r h i s a In d i f f e r e n t ways: The b e t t e r a v a i l a b i l i t y o f n u t r i e n t s i n t h e s t e r i l e v a r i a n t ( I I ) dl:r i n g the time o f a p D l i c a t i o n ( t a b . l ) d i d n o t cause a h i g h e ~ r a t e o f p l a n t growth ( t a b . 2 ) ; t h e manures did I n f l u e n c e t h e e f f i c i e n c y o f t h e VA mycorr h i z a l i n o c u l a t i o n . The comeost from s t a b l e manure always caused p o o r e r growth o f the i n o c u l a t e d p l a n t s . In c o n t r a s t , m y c o r r h i z a l e f f e c t s were maintained w i t h i n c r e a s i n g amounts o f s t e r i l i z e d s t a b l e manure and comp o s t based on p l a n t r e m a i n s ; o n l y w i t h t h e h i g h e s t amount o f manure i n both t r e a t m e n t s d id t h e N~ p l a n t s grow much b e t t e r than t h e M p l a n t s . P a r a s i t i c e f f e c t o f t h e VA m y c o r r h i z a could perhaps e x o l a i n t h e n e g a t i v e r e s u l t s of t h e i n o c u l a t i o n i n t h e s e s t e r i l e t r e a t m e n t s . I t i s w e l l known t h a t t h e R ¥ c o r r h i z a l e f f e c t s can become p a r a s i t i c i f t h e r e i s a ones i d e d advantage f o r one of th e p a r t n e r s (BROWN and CARR 1984, PACOVSK¥ e t e l . 1985), f o r example~ th e f u n g i consuming l a r g e amounts o f a s s i m i l a t e s from t h e h o s t p l a n t (,TORNSON 1984). M y c o r r h i z a l p l a n t s g e n e r a l l y grew b e t t e r w i t h u n s t e r i l e manure compared with t h e s t e r i l e m a t e r i a l s , when t h e p o s s i b l e n u t r i e n t s o u r c e s provided by t h e manures were low
(BRZCH~T,'~1968). For two manures t h e f r e s h o r g a n i c m a t e r i a l caused a b e t t e r development o f the m y c o r r h i z a l i n f e c t i o n ~han t h e s t e r i l e form ( t a b . 3 ) . F r e s h o r g a -
Table 1. ? content of the organic manure (mg/g PM) |,
I
Manures
Total
P Availability
P
aid
,
Stable manure
I II Compost (staI b l e manure) II Compost (plant- I remains) II
le
low
4.15
3.26
3~
48%
49%
4s%
48'
2.82
4% 4~
62~
34~
5%
66%
29% II
IIII
I
57
Tab l e 2. Shoot dry weight (g DM) o f Capsicum annuum w i t h (M) and w i t h o u t (NM) mycorrhiza w i t h i n c r e a s i n g a p p l i c a t i o n s o f orgartic manure (E~O, 1=50, 2=100, 3=200, ~=3OO d r / h a ) I = fresh
II = sterile
Stablemanure
NM
0.13 0,06
0.52 0.32
0.95 0.75
1 , 2 5 1.95 1 . 3 1 1.99
0.13 0,06
0.25 0.2~
0.43 0.22
1.24 0.35
1.47 1.7~
0,13 0.06
0.1~ 0.21
0.31 0.38
0.56 0.98
0.93 1.42
0.~ 0.0~
0.~ 0.~
0.~2 0.~1
~.09 0.49
~.~
GD5%=0.17 Compost from stable manure
M H~
0.13 0.22 0.66 1 . 3 1 2.21 0.06 0.27 0.35 0.80 1 . 8 1 6~5%=o.o8 Compost based on plant remains .. ,.
0.0~ 0.0~
0.27 0.10
~.o.
~
0.61 0.~1
~.4~ ~.0~
.
.
~.~ 1,88 .
.
~.08
.
Table 3. R y o o r r h i z a i n f e c t i o n r a t e (%) and l n t e n s i t ~ o f Capsicumannuu m wi~h i n c r e a s i n g a p ~ l i o a t i o n s of o r g a n i c manure (E=O, 1=~0, 2=100, 3=200, 4=300 dr/ha) I = fresh
~
2
~
4
•
II : sterile
1
2
3 ....
4
S t a b l e manure M ~
V= Rate
~XX
~X
XX
XX
X~
XXX
XX
XX
XX
XXX
X
X
X
X
-
X
-
X
X~
XX
25% 8% 4% 6% Compost from stable manure V= Rate
25%
4%
4%
8%
20~
XXX
XXX
~XX
XXX
XXX
XXX
XXX
XX
XX
X
XX
XX
XX
X
XXX
X~
X
-
25~
24%
17%
15%
11%
25%
15%
12%
¢x
~xx
xx
xx
x~
x
X
X
X
-
-
-
Compost based on ~ l a n t remains x~x xxx ¢xx x~ X X~ X X V"
~ate
6~
2~
30~
20~
1~
5~
25~
~,;
e~
"
7%
5~
2~
3%
= M=~Tcelium, V = Veslcles (Arbuscules Gould not be found) Intensltyz - = none, x = low, xx = middle, ~xx = hlgh
n i e manures can s t i m u l a t e the growth o f f u n g a l hyphae d e v e l o p i n g from myeorrhiza (ST.JOHN e t a i , 1983) and the f u n g i can s u r v i v e s a p r o p h y t l c a l y in o r g a n i c p a r t i c l e s (WARNER 1984), which would f a v o u r f u r t h e r i n f e c t i o n during th e v e g e t a t i o n p e r i o d (SCH~MBECE 1984),. This t o g e t h e r w~th an e v e n t u a l s y n e r g i s t i c e f f e c t of o t h e r s o i l microorganisms may e x p l a i n t h e b e t t e r i n f e c t i o n develop.~ent in th e t m s t e r l l e t r e a t m e n t s .
5S
References BRECHELT, A., 1987= Wirkuns v e r s c h i e d e n e r o r g a n t s c h e r D~ngemlttel auf d i e E f f t z i e n z der VA-iykorrhiza. J.Agronoo~7 & Crop Science 458, 280-286. BRE~ELT, A. p 1988s EinfluB v e r s c h i e d e n e r organlsoher D ~ g e m l t t e l auf d i e E f f i s t e r m tier V&-lykorrhisa und e i n i g e r N i - f i x i e r e n d e r B a k t e r i e n lm Boden be£ t r o p i s c h e n und s u b t r o p i s c h e n Pflansen. GOttlnger B e i t r ~ e zur I c e d - und P o r s t w i r t s c h a f t i n den Tropen und 8ubtropen. H.~2, GSttingen. BEINERT, K°, SAUERLANDT, W., 1951s Der w t r t e o h a f t s e l g e n e lXfnger. Paul Parey, Berlin. BROWN, U.E., CARR, G.R., 1984s I n t e r a c t i o n s between A s o t o b a c t e r chrooooc• sum and V& m~corrhiza and t h e i r e f f e c t s on s l a n t growth. J . A p p l . B a o t e r l o l . 56, 429-43T. J~0GI, W., 191'4s Bodenmikrobtologtsohe Untersuohungen In einem DUngungeo versueh. Sohwetsertsche Landw.Porsohung ~ ( 1 / 2 ) , 5~1-547. JOHWSON, C.R., 1984s Phosphorus n u t r i t i o n on myeorrhlzal c o l o n i z a t i o n , p h o t o s y n t h e s i s , growth and n u t r i e n t composition of C i t r u s a u r a n t l u = . Plant and Soi~ 80, 35-42. I~tKAWI, A.A.M., 1982s Local o r g a n l c manures and t h e i r e f f e c t on s o i l m i o r o f l o r a and wheat y i e l d . FAO S o i l Bull.45s Organic m a t e r i a l s and s o i l p r o d u c t i v i t y in the near e a s t , Rome, 144-148. ~ISHRA, L i l . , TAUR0, P . , 1983s Use of organic f e r t i l i z e r s v i s - a - v i s miner a l f e r t i l i z e r s . Ins Asian P r o d u c t i v i t y Organization ( e d t . ) . Recycl i n g organic matter in a s i a f o r f e r t i l i z e r use. Report of a study meet i n g on organic f e r t i l i z e r , Tokyo/Japan, 9-9-39. PACOVSKY, R.S., F U I J ~ , G., PAUL, E.A., q985s Influence of s o i l on t h e i n t e r a c t i o n s between endomyoorrhtza and A z o s p i r i l l u m in sorghum. 8 o t l
Biol.Bloohem. 17 (4), 525-5~I. SCH~NBECE, P . , 1980! Endomykorrhiza. ~kologie, Funktion und phytopatholo-" gischs Aspekte. Forum ~ k r o b . ~ ( 2 ) , 90-96. SCHOHB£CK, P . , 1984s ~ n d o ~ o o r r h t s a . Progress in Botany 46, ~82-~92. ST.~0~N, T.V., COLEMAN, D.C., REID, C.P.Po, 198~s A s s o c i a t i o n of VA my_ o o r r h i z a l hyphae wt~h s o i l o r g a n i c p a r t i c l e s . Ecology 64 ( 4 ) , 957-959° WAR~ER, A., 1984! Colonization o f o r g a n i c matter by VA myoorrhizal fungi. T r a n e . ~ r . t ~ c o l . S o c . S_~ (2), ~52-~54.
Brechelt, A., 1989: Effect of different organic manures on the efficiency of VA-mycorrhiza. Agrlc. Ecosystems Envlrcn., 29: 55-58.
Agriculture, Ecosystems and E~vironment, 29 (1989) 55-58 Elsevier Science Publishers B.V., Amsterdam Printed in Czechoslovakia
E f f e c t of d i f f e r e n t
o r g a n i c manures on t h e e f f i c i e n c y o f VA mycorrhiza
Andrea B r e c h e l t I n s t i t u t ftlr Pflanzenbau und T i e r h y g i e n e i n den Tropen und Subtropen d e r G e o r g - A u g u e t - U n i v e r s i t ~ t G 0 t t i n g e n , G r i s e b a o h s t r . 6 , D-~400 G~ttingen A_bstract The i n f l u e n c e o f s t e r i l i z e d and u n s t e r i l i z e d s t a b l e manure and two d i f f e r e n t k i n d s of compost on t h e e f f i c i e n c y of VA m y c o r r h i z a l n ~ . ~ aioum annuum was examined. The magnitude of t h e p o s i t i v e e f E e o t o f VA mycorrhlza on p l a n t y i e l d d e c r e a s e d w i t h i n c r e a s i n g amounts o f o r g a n i c manure due t o b e t t e r growth of the n o n m y c o r r h i z a l p l a n t s . Co,spared with t h e s t e r i l e t r e a t m e n t s , the m y c c r r h i z a l e f f e c t was b e t t e r with u n s t e r l l e manures when t h e p o s s i b l e n u t r i e n t s o u r c e s provided by t h e manures were low. Introduction I t has p r e v i o u s l y been shown t h a t t h e e f f i c i e n c y of VA m y c o r r h i z a on p l a n t y i e l d always decreased with i n c r e a s e d amounts of f r e s h o r g a n i c manures (BRECHELT 1987). The r a t e o f t h i s r e d u c t i o n was n o t dependent only on t h e n u t r i e n t c o n t e n t s of t h e manures. In ol'der examine the r o l e of the n u t r i e n t s and the r e a s o n s f o r d i f f e r e n t i n f l u e n c e s of o r g a n i c manures, u n s t e r i l e m a t e r i a l was compared with t h e e f f e c t of t h e c o r r e s ponding amounts of the same manures in a s t e r i l e and ho~,Loseneous form. M a t e r i a l and Ne~hods The VA m y c o r r h i z a l funsu~ Acaulos~ora l o n g u l a (SIEVERDING p e r s . i n f o r mation) was grown on Capsicum annuu~ i n a poor f o r e s t s o i l as d e s c r i b e d by BRECHELT (1988). To compare t h e i n f l u e n c e of s t a b l e manure, compost from s t a b l e manure and compost based on p l a n t remains ( v a l i a n t I) w i t h t h e i r c o r r e s p o n d i n g amounts in a s t e r i l e form ( v a r i a n t I I ) , the manures were s t e r i l i z e d ~20aC f o r 8 h o u r s ) and ground b e f o r e a p ~ l i c a t i o n , t h e manures were added a t 4 c o n c e n t r a t i o n s r ~ 0 , 100, 200, ~00 d r / h a . T h e i r phosphorus c o n t e n t i s given in t a b l ~ 1t f o r a l l t h e o ! h e r n u t r i e n t s and l n f o r m a t i o n s eee
BRECHELT (1988). Inoculation of the experlmental plants with AcaulosDora lon~ula took p l a c e a t t r a n s p l a n t a t i n g i n t o 1 k g - p o t s usin~ i n f e c t e d p l a n t r o o t s o f Eupatorium odoratum.
Results and Dieousslon As r e c e n t l y shown (BRECHELT 1987), i n c r e a s e d amounts o f f r e s h o r g an i c m a t e r i a l ( I ) l e d t o a decrease i n myoorrhiza e f f i c i e n c y ( t a b . 2 ) .
The
56
increasing n u t r i e n t concentrations of the s o i l in treatments with higher amounts o f o r g a n i c manures caused t h i s r e d u c t i o n (SCH~BECK 1980). Higher amounts of t h e d i f f e r e n t t y p e s o f manures reduced d i f f e r e n c e s between t h e i n o c u l a t e d (M) and non i n o c u l a t e d (NM) p l a n t s more o r l e a s q u i c k l y dependin~ on t h e s t a g e o f m a t u r i t y and t h e kind o f s t a r t i n g m a t e r i a l . The r e s u l t s were l i t t l e i n f l u e n c e d by t h e a v a i l a b i l i t y o f n u t r i e n t s ( t a b . l ) dur i n g th e time o f a p p l i c a t i o n . The a c t i v i t y o f s o i l 1microorganisms Drobably improved t h e a v a i l a b i l i t y o f t h e n u t r i e n t s d u r i n g t h e v e g e t a t i o n p e r i o d . This p r o c e s s can v a r y in i n t e n s i t y d ecen d i n g on t h e o r g a n i c t r e a t m e n t (BRECHELT 1987). M i c r o b i a l a c t i v i t y can a l s o f i x n u t r i e n t s (J~GGI 1974),
produce antibiotic substances (BEINE~T and SAUERLANDT 1951), enzymes (J~GGI 19~4), organic acids and influence other microorganisms (MAI~AWI 1982, MIS~RA and TA~HO 198~), any o f which could a f f e c t
the efficiency
o f the VA m y c o r r h i s a In d i f f e r e n t ways: The b e t t e r a v a i l a b i l i t y o f n u t r i e n t s i n t h e s t e r i l e v a r i a n t ( I I ) dl:r i n g the time o f a p D l i c a t i o n ( t a b . l ) d i d n o t cause a h i g h e ~ r a t e o f p l a n t growth ( t a b . 2 ) ; t h e manures did I n f l u e n c e t h e e f f i c i e n c y o f t h e VA mycorr h i z a l i n o c u l a t i o n . The comeost from s t a b l e manure always caused p o o r e r growth o f the i n o c u l a t e d p l a n t s . In c o n t r a s t , m y c o r r h i z a l e f f e c t s were maintained w i t h i n c r e a s i n g amounts o f s t e r i l i z e d s t a b l e manure and comp o s t based on p l a n t r e m a i n s ; o n l y w i t h t h e h i g h e s t amount o f manure i n both t r e a t m e n t s d id t h e N~ p l a n t s grow much b e t t e r than t h e M p l a n t s . P a r a s i t i c e f f e c t o f t h e VA m y c o r r h i z a could perhaps e x o l a i n t h e n e g a t i v e r e s u l t s of t h e i n o c u l a t i o n i n t h e s e s t e r i l e t r e a t m e n t s . I t i s w e l l known t h a t t h e R ¥ c o r r h i z a l e f f e c t s can become p a r a s i t i c i f t h e r e i s a ones i d e d advantage f o r one of th e p a r t n e r s (BROWN and CARR 1984, PACOVSK¥ e t e l . 1985), f o r example~ th e f u n g i consuming l a r g e amounts o f a s s i m i l a t e s from t h e h o s t p l a n t (,TORNSON 1984). M y c o r r h i z a l p l a n t s g e n e r a l l y grew b e t t e r w i t h u n s t e r i l e manure compared with t h e s t e r i l e m a t e r i a l s , when t h e p o s s i b l e n u t r i e n t s o u r c e s provided by t h e manures were low
(BRZCH~T,'~1968). For two manures t h e f r e s h o r g a n i c m a t e r i a l caused a b e t t e r development o f the m y c o r r h i z a l i n f e c t i o n ~han t h e s t e r i l e form ( t a b . 3 ) . F r e s h o r g a -
Table 1. ? content of the organic manure (mg/g PM) |,
I
Manures
Total
P Availability
P
aid
,
Stable manure
I II Compost (staI b l e manure) II Compost (plant- I remains) II
le
low
4.15
3.26
3~
48%
49%
4s%
48'
2.82
4% 4~
62~
34~
5%
66%
29% II
IIII
I
57
Tab l e 2. Shoot dry weight (g DM) o f Capsicum annuum w i t h (M) and w i t h o u t (NM) mycorrhiza w i t h i n c r e a s i n g a p p l i c a t i o n s o f orgartic manure (E~O, 1=50, 2=100, 3=200, ~=3OO d r / h a ) I = fresh
II = sterile
Stablemanure
NM
0.13 0,06
0.52 0.32
0.95 0.75
1 , 2 5 1.95 1 . 3 1 1.99
0.13 0,06
0.25 0.2~
0.43 0.22
1.24 0.35
1.47 1.7~
0,13 0.06
0.1~ 0.21
0.31 0.38
0.56 0.98
0.93 1.42
0.~ 0.0~
0.~ 0.~
0.~2 0.~1
~.09 0.49
~.~
GD5%=0.17 Compost from stable manure
M H~
0.13 0.22 0.66 1 . 3 1 2.21 0.06 0.27 0.35 0.80 1 . 8 1 6~5%=o.o8 Compost based on plant remains .. ,.
0.0~ 0.0~
0.27 0.10
~.o.
~
0.61 0.~1
~.4~ ~.0~
.
.
~.~ 1,88 .
.
~.08
.
Table 3. R y o o r r h i z a i n f e c t i o n r a t e (%) and l n t e n s i t ~ o f Capsicumannuu m wi~h i n c r e a s i n g a p ~ l i o a t i o n s of o r g a n i c manure (E=O, 1=~0, 2=100, 3=200, 4=300 dr/ha) I = fresh
~
2
~
4
•
II : sterile
1
2
3 ....
4
S t a b l e manure M ~
V= Rate
~XX
~X
XX
XX
X~
XXX
XX
XX
XX
XXX
X
X
X
X
-
X
-
X
X~
XX
25% 8% 4% 6% Compost from stable manure V= Rate
25%
4%
4%
8%
20~
XXX
XXX
~XX
XXX
XXX
XXX
XXX
XX
XX
X
XX
XX
XX
X
XXX
X~
X
-
25~
24%
17%
15%
11%
25%
15%
12%
¢x
~xx
xx
xx
x~
x
X
X
X
-
-
-
Compost based on ~ l a n t remains x~x xxx ¢xx x~ X X~ X X V"
~ate
6~
2~
30~
20~
1~
5~
25~
~,;
e~
"
7%
5~
2~
3%
= M=~Tcelium, V = Veslcles (Arbuscules Gould not be found) Intensltyz - = none, x = low, xx = middle, ~xx = hlgh
n i e manures can s t i m u l a t e the growth o f f u n g a l hyphae d e v e l o p i n g from myeorrhiza (ST.JOHN e t a i , 1983) and the f u n g i can s u r v i v e s a p r o p h y t l c a l y in o r g a n i c p a r t i c l e s (WARNER 1984), which would f a v o u r f u r t h e r i n f e c t i o n during th e v e g e t a t i o n p e r i o d (SCH~MBECE 1984),. This t o g e t h e r w~th an e v e n t u a l s y n e r g i s t i c e f f e c t of o t h e r s o i l microorganisms may e x p l a i n t h e b e t t e r i n f e c t i o n develop.~ent in th e t m s t e r l l e t r e a t m e n t s .
5S
References BRECHELT, A., 1987= Wirkuns v e r s c h i e d e n e r o r g a n t s c h e r D~ngemlttel auf d i e E f f t z i e n z der VA-iykorrhiza. J.Agronoo~7 & Crop Science 458, 280-286. BRE~ELT, A. p 1988s EinfluB v e r s c h i e d e n e r organlsoher D ~ g e m l t t e l auf d i e E f f i s t e r m tier V&-lykorrhisa und e i n i g e r N i - f i x i e r e n d e r B a k t e r i e n lm Boden be£ t r o p i s c h e n und s u b t r o p i s c h e n Pflansen. GOttlnger B e i t r ~ e zur I c e d - und P o r s t w i r t s c h a f t i n den Tropen und 8ubtropen. H.~2, GSttingen. BEINERT, K°, SAUERLANDT, W., 1951s Der w t r t e o h a f t s e l g e n e lXfnger. Paul Parey, Berlin. BROWN, U.E., CARR, G.R., 1984s I n t e r a c t i o n s between A s o t o b a c t e r chrooooc• sum and V& m~corrhiza and t h e i r e f f e c t s on s l a n t growth. J . A p p l . B a o t e r l o l . 56, 429-43T. J~0GI, W., 191'4s Bodenmikrobtologtsohe Untersuohungen In einem DUngungeo versueh. Sohwetsertsche Landw.Porsohung ~ ( 1 / 2 ) , 5~1-547. JOHWSON, C.R., 1984s Phosphorus n u t r i t i o n on myeorrhlzal c o l o n i z a t i o n , p h o t o s y n t h e s i s , growth and n u t r i e n t composition of C i t r u s a u r a n t l u = . Plant and Soi~ 80, 35-42. I~tKAWI, A.A.M., 1982s Local o r g a n l c manures and t h e i r e f f e c t on s o i l m i o r o f l o r a and wheat y i e l d . FAO S o i l Bull.45s Organic m a t e r i a l s and s o i l p r o d u c t i v i t y in the near e a s t , Rome, 144-148. ~ISHRA, L i l . , TAUR0, P . , 1983s Use of organic f e r t i l i z e r s v i s - a - v i s miner a l f e r t i l i z e r s . Ins Asian P r o d u c t i v i t y Organization ( e d t . ) . Recycl i n g organic matter in a s i a f o r f e r t i l i z e r use. Report of a study meet i n g on organic f e r t i l i z e r , Tokyo/Japan, 9-9-39. PACOVSKY, R.S., F U I J ~ , G., PAUL, E.A., q985s Influence of s o i l on t h e i n t e r a c t i o n s between endomyoorrhtza and A z o s p i r i l l u m in sorghum. 8 o t l
Biol.Bloohem. 17 (4), 525-5~I. SCH~NBECE, P . , 1980! Endomykorrhiza. ~kologie, Funktion und phytopatholo-" gischs Aspekte. Forum ~ k r o b . ~ ( 2 ) , 90-96. SCHOHB£CK, P . , 1984s ~ n d o ~ o o r r h t s a . Progress in Botany 46, ~82-~92. ST.~0~N, T.V., COLEMAN, D.C., REID, C.P.Po, 198~s A s s o c i a t i o n of VA my_ o o r r h i z a l hyphae wt~h s o i l o r g a n i c p a r t i c l e s . Ecology 64 ( 4 ) , 957-959° WAR~ER, A., 1984! Colonization o f o r g a n i c matter by VA myoorrhizal fungi. T r a n e . ~ r . t ~ c o l . S o c . S_~ (2), ~52-~54.
Brechelt, A., 1989: Effect of different organic manures on the efficiency of VA-mycorrhiza. Agrlc. Ecosystems Envlrcn., 29: 55-58.