Allelochemicals: Role in Agriculture and Forestry - American Chemical

Chapter 9 Allelopathy in Mexico A . L . Anaya, L . Ramos, J . G . Hernandez, and R . Cruz

Downloaded by UNIV OF SOUTHERN CALIFORNIA on August 12, 2013 | http://pubs.acs.org Publication Date: January 8, 1987 | doi: 10.1021/bk-1987-0330.ch009

Institute de Fisiología Celular, Departamento de Bioenergética, U N A M . Apdo., Postal 70-600, 04510 Mexico, D. F . Mexico

Studies of allelopathy in Mexico were initiated in 1970 within the project entitled Recovery of Tropical Rain Forests. This paper summarizes the main results obtained from: research about the allelopathic potential of some tropical secondary plants in Veracruz; studies in coffee plantations (herbs, coffee shrubs, and shade trees); the discovery of the allelopathic potential of water hyacinth, and the use of this plant as fertilizer in the "chinampas"; the relationships of crops and weeds in "chinampas" and the allelopathic properties of corn pollen. Likewise studies on Helietta parvifolia and Piqueria trinervia are mentioned and finally research that is in progress in temperate and tropical agroecosystems in order to permit more efficient agricultural and forest management of the agroecosystems in Mexico is mentioned, mainly the biological control of weeds and pests, the use of green manures and composts, and the management of water and b i o l o g i c a l d i v e r s i t y . The studies on allelopathy i n Mexico were i n i t i a t e d i n 1970 within the project e n t i t l e d Recovery of Tropical Rain Forests, as a suggestion of i t s d i r e c t o r , Dr. Arturo Gomez-Pompa, at the Institute of Biology of the National Autonomous University of Mexico. Studies of Secondary Vegetation The main objective of this project was to study some of the ecological processes that occur during secondary succession i n warm a n d h u m i d tropics. This process i s triggered a f t e r a perturbation i n the t r o p i c a l rain forest or the abandonment of crop land (1_»2) . The quantity and quality of leached plant metabolites, i n warm and humid regions, suggest that there exists a great variety of complex interactions among plants and microorganisms. In 1970, studies on allelopathy i n the t r o p i c a l zones were scarce, p a r t i c u l a r l y i n Mexico. The contributions of McPherson (3), F r e i and Dodson (4), Quarterman C5), Webb, Tracey and Haydock (6), Marinero (7) , and Gliessman (8) are some important antecedents for the study 0097-6156/87/0330-0089$06.00/0 © 1987 A m e r i c a n C h e m i c a l Society

In Allelochemicals: Role in Agriculture and Forestry; Waller, G.; ACS Symposium Series; American Chemical Society: Washington, DC, 1987.


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ALLELOCHEMICALS: ROLE IN AGRICULTURE AND FORESTRY

that was carried out concerning the a l l e l o p a t h i c potential of the secondary vegetation i n Veracruz, Mexico (9) at the b i o l o g i c a l station of the National Autonomous University of Mexico located at Los Tuxtlas. In t h i s place we selected the most abundant species i n order to detect their a l l e l o p a t h i c p o t e n t i a l . The species were: Piper auritum, Piper hispidum, Croton pyramidalis, Siparuna nicaraguensis, and Cecropia o b t u s i f o l i a . The aqueous extracts of roots and leaves, the leachates of a e r i a l parts, aqueous extracts of s o i l s and i n some cases organic s extracts of leaves, the essential o i l s , and isolated pure compounds were tested for their e f f e c t s upon germination and growth of several test species from the same area. Likewise, bioassays of simultaneous germination were carried out with some of the available seeds. The test seeds used for the bioassays were: Mimosa pudica, Achyranthes aspera, Bidens p i l o s a , and Crusea calocephala (herbaceous species); Ochroma lagopus and Heliocarpus donell-smithii (arboreal species). F i r s t the tolerance of these species to osmotic pressure was determined i n order to avoid interference of this factor with the results (10). Then we tested the following aqueous extracts of leaves, made with 1 and 4 g of dried leaves at 30°C , and 100 mL of d i s t i l l e d water i n a blender. Root extracts were made with 15 g of plant i n 100 mL of d i s t i l l e d water. The a e r i a l parts were leached by soaking 100 g of fresh plants i n 100 mL of d i s t i l l e d water. S o i l extracts were prepared i n a 2:1 proportion. The organic extracts of leaves were obtained with the following solvents: hexane, ethyl acetate, chloroform, benzene, acetone, and methanol. The essential o i l s were obtained by steam d i s t i l l a t i o n and the pure substances with several extraction techniques (11, 12, 14). A l l materials were tested upon seeds i n P e t r i dishes with agar (1%) or f i l t e r paper as substrate, at 27°C and a 12-h photoperiod. Lengths of roots and stems were measured and the percent of germination was calculated. A l l results were s t a t i s t i c a l l y analyzed with an F^ test. The bioassays showed the wide a l l e l o p a t h i c potential of these plants as well as the phytotoxicity of some s o i l s extracts and essent i a l o i l s (Tables I, I I , and I I I ) . A l l species studied inhibited the growth of certain test species. This confirms the s e l e c t i v i t y of the a l l e l o p a t h i c compounds (15). The species with the higher a l l e l o p a t h i c potentials were: Piper auritum, Piper hispidum, Croton pyramidalis, and Siparuna nicaraguens i s . The essential o i l s of the Piperaceae were highly i n h i b i t o r y while that of Croton pyramidalis was less i n h i b i t o r y and even produced stimulations (Table I I I ) . A very interesting result was the i s o l a t i o n of safrole from the essential o i l of Piper auritum. This compound i s abundant i n the Monimiaceae and Lauraceae families. It was found to constitute 60 to 70% of the essential o i l of P.auritum (16). The benzenic extract from leaves of Croton pyramidalis was highly i n h i b i t o r y . From t h i s extract we isolated a flavone and a diterpene (Figure 1) but there are other compounds not yet i d e n t i f i e d i n this extract

that

a r e much more t o x i c

( V\_) .

The tests of simultaneous germination with seeds of Siparuna n i c a -



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91

Mexico

T a b l e I . E f f e c t s o f the E x t r a c t s o f Leaves and Roots of P i p e r a u r i t u m , _P. h i s p i d u m , C r o t o n p y r a m i d a l i s , C e c r o p i a o b t u s i f o l i a , and S i p a r u n a n i c a r a g u e n s i s on R a d i c l e Growth o f Some Secondary Species

1

Treatments

Inhibition/Stimulation (%) Piper Piper Croton Cecropia auritum hispidum pyramidalis obtusifolia L e a f Root L e a f Root L e a f Root L e a f Root

Siparuna nicaraguensis Root Leaf

Species : Mimosa pudica

59

2

27

A.aspera

42

2

(44)

B.pilosa

68

2

28

2

(75)

Crusea calccephalf 3 5 H.donne11 47 smithii 0.lagopus

mean of

3

2

11

five

2

2

2

67

2

21

(67 Ϋ

49

2

(22)

(11)

56

2

17

2

79 76

2

_

21

56

2

2

2

100 86

2

24

2

2

3

(42)

2

_

18

3

25

15

2

66

2

56

2

37

2

2

3

(49)

2

_

31

2

51

2

2

(13)

3

54

(29)

2

52

0

64

(11)

5

4

(8)

_

51

41

0

(3)

2

t o the 1% l e v e l .

significant

t o the 5% l e v e l .

11

(9) 2

repetitions.

significant

8 (7)

2

(3)

2

2

Numbers i n p a r e n t h e s i s a r e s t i m u l a t i o n s .


_

8


92


Table I I . Effects of the Aqueous Extracts of Soils Associated with Piper auritum, P_. hispidum, Croton pyramidalis, Cecropia o b t u s i f o l i a , and Siparuna nicaraguensis on the Radicle Growth of Some Secondary Species

1

Treatments

Inhibition/Stimulation (%) Piper Piper Croton Cecropia Siparuna auritum hispidum pyramidalis o b t u s i f o l i a njcaraguensis

Species : Mimosa pudica

3

12.4

10.7

0

11

A.aspera

(6)

24

2

(16)

B.pilosa

9.4

21

2

18

25

2

(3)

24

2

34

Crusea calocephala

19.2

H. donnellsmithii

20

0.lagopus

Mean of f i v e

2

2

3

10

3

2

6

3

(7)

10

(4) 15

3

11 (20)

10

14

3

(77)

25

2

repetitions.

2

s i g n i f i c a n t to the 1% level.

3

s i g n i f i c a n t to the 5% level.

Numbers i n parenthesis are stimulations.


2

2

(87)

2

9.

Table


Allelopathy

ANAYA ET AL.

III.

E f f e c t s of the E s s e n t i a l O i l s of Piper auritum, Piper hispidum, and C r o t o n p y r a m i d a l i s ( 1 0 0 ppm), on t h e Growth ( R a d i c l e and Stem) o f Some Secondary S p e c i e s

Treatments Species

93

in Mexico

^^"^^^

1

inhibition/stimulation (%) Piper auritum Piper hispidum Croton Stem Root Stem Root Root

pyramidalis Stem

3

(55)

2

90

2

100

2

100

2

100

2

100

2

84

2

34

2

2

100

2

100

2

100

2

49

2

27

2

100

2

100

2

(5)

15

3

Heliocarpus donnell-smithii

91

2

100

2

16

3

Ochroma lagopus

74

2

100

2

100

2

100

2

Mimosa

pudica

Achyranthes aspera Bidens

pilosa

Crusea calocephala

Solanum n i t e n s

Mean from f i v e

3

87

2

81

2

100

91

-

_

100

2

2

-

100

100

2

100

2

1 9

(22)

2

(26)

2

-

repetitions.

significant

t o t h e 1% l e v e l .

significant

t o t h e 5% l e v e l .

Numbers i n p a r e n t h e s i s

are stimulations.


(35)

-

2

2


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ALLELOCHEMICALS: ROLE IN AGRICULTURE AND

FORESTRY

raguensis showed that they are i n h i b i t o r y to the germination and growth of other test seeds. Rodriguez-Hahu (personal communication) mentioned that this e f f e c t i s due to a terpene, a rhamnoside and a flavonol, among other substances that are not yet i d e n t i f i e d . As part of the same project a study of one of the most common weeds i n some disturbed habitats from many regions i n Los Tuxtlas (Veracruz) was carried out. Ambrosia cumanensis i s found as an important species of the ruderal vegetation. It grows vigorously and i n almost pure stands. We decided to assess i t s a l l e l o p a t h i c p o t e n t i a l i n order to evaluate this phenomenom as a determining factor for the structure of the community as well as i n the secondary succession process. Root and leaf aqueous leachates of Ambrosia cumanensis did indeed produce a strong i n h i b i t i o n on the growth of weed species. Aqueous extracts of s o i l c o l l e c t e d under A.cumanensis i n July (during i t s flowering) were strongly a l l e l o p a t h i c to weed growth. Decomposition of leaves and roots i n pots caused i n h i b i t i o n of some weeds also. Microorganisms have a major r o l e i n this process, as shown by results from s t e r i l e and nonsterile s o i l s (17). Bioassays with several sesquiterpene lactones from A. cumanensis showed that these compounds produce d i f f e r e n t e f f e c t s (stimulatory and i n h i b i t o r y ) on the germination and growth of several species of the secondary vegetation (18). Therefore, i t i s possible that the a l l e l o p a t h i c p o t e n t i a l of A. cumanensis contributes to the autocontrol of i t s population by preventing the growth of seedlings of i t s own species (Figure 2). The information obtained at Los Tuxtlas shows that the studied species from the secondary vegetation produce one or more a l l e l o p a t h i c substances, mainly i n leaves or through the decomposition of t h e i r organic matter, that can i n h i b i t growth or have deleterious e f f e c t s on plants and may cause p a r a l l e l effects that are related to the r o l e of auxins and to tropisms and other metabolic processes. The production of a l l e l o p a t h i c compounds i n t r o p i c a l zones, p a r t i c u l a r l y i f they are continuously released into the environment, may contribute to the elimination of secondary species already established and to the s e l e c t i o n of those that are beginning to e s t a b l i s h i n the habitat. Studies i n Coffee

Plantations

In 1979, we decided to extend our studies to one of the agroecosystems of greater importance i n Mexico: the coffee plantations. These studies were r e a l i z e d within the Program of Agroecosystems at the-Instituto Nacional de Investigaciones sobre Recursos B i o t i c o s . We worked at the coffee plantations i n Coatepec, Veracruz, which are characterized by the presence of shade trees which resemble the structure of the deciduous temperate f o r e s t s , with three well defined s t r a t a : the herbaceous layer, the shrub layer represented by coffee plants and the tree layer. The main objective of this study was to assess the a l l e l o p a t h i c i n t e r actions among the species that constitute this community, i n p a r t i c u l a r the coffee plants (19). Figure 3 shows the e f f e c t of the s o i l extracts from the coffee plantation. Waller et a l . mention that these effects might be explained by the accumulation of caffeine and other alkaloids i n s o i l i n old coffee plantations (20). The greatest a l l e l o p a t h i c e f f e c t s were produced by plants from the


9.

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ANAYA ET AL.

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Mexico


MeO

OAc CH OAc 2

Diterpene

F i g u r e 1.

S t r u c t u r e s of P y r a m i d o l a c t o n e ( F u r o l a c t o n e D i t e r p e n e ) of the N o r c l e r o d a n e group ( A ) , and 3 , 5 - d i h y d r o x y - 7 , 4 dimethoxyflavone (B) i s o l a t e d from Croton pyramidalis. f

H

U

0 H

Cumambrin A

Cumambrin Β

Psilostachyin Β

HO

Psilostachyin C Figure 2.

Peruvin

Cumanin

S e s q u i t e r p e n e l a c t o n e s i s o l a t e d from cumanensis-psilo stachya complex.

the

Ambrosia


96

ALLELOCHEMICALS: ROLE IN AGRICULTURE AND

FORESTRY

herbaceous layer (Figure 4), p a r t i c u l a r l y from various species of Commeliriaceae. These results led us to the study of three of the most abundant species i n the coffee orchards: Commelina d i f f u s a , Tripogandra serrulata, and Zebrina sp. A l l species, fresh, dried, and chopped, as well as their l i t t e r , exerted a s i g n i f i c a n t i n h i b i t i o n i n the growth of Bidens p i l o s a (21).


Studies on Water Hyacinth Simultaneous to the studies at the coffee plantation was the study of the a l l e l o p a t h i c potential of the water hyacinth (Eichornia crassipes). This aquatic plant, introduced i n Mexico at the beginning of this century, invades many of the water reservoirs and streams and i s considered as one of the worst aquatic weeds i n our country. Its capacity to establish i t s e l f i n several water habitats and i t s extensive vegetative growth suggested a strong mechanism of invasion, perhaps of a l l e l o p a t h i c nature. Several bioassays were used for testing aqueous extracts from leaves, roots, and flowers upon weeds and cultivated plants. Results showed a strong i n h i b i t o r y e f f e c t , e s p e c i a l l y from leaves and flower leachates (Figure 5). Water hyacinth i s widely used as a green f e r t i l i z e r i n the Valley of Mexico, mainly i n the ancestral t r a d i t i o n a l agroecosystems known as "chinampas". These are long narrow s t r i p s of land surrounded on at least three sides by water. Once the a l l e l o p a t h i c potential of water hyacinth was demonstrated i n laboratory assays, we decided to study the e f f e c t of this plant upon the a g r i c u l t u r a l production and growth of weeds i n a chinampa where turnip, radish, lettuce, and cabbage were cultivated. The s o i l i n the chinampa was prepared i n the t r a d i t i o n a l way of peasants at Xochimilco, by making a seed bed with mud from the bottom of the channels that surround the chinampa. When the mud was dry, i t was cut i n small cubes where the seeds were planted. The seedbed was then covered with s o i l and twigs. Once the seedlings reached 10-15 cm they were transplanted to a plot previously weeded and plowed. Treatments were placed randomly and covered with mud. These were: 1. control (without f e r t i l i z e r ) ; 2. inorganic f e r t i l i z e r (10:10:15), 250 g/m ; 3. cow manure; 4. water hyacinth (whole plant); 5. water hyacinth (roots); 6. water hyacinth ( a e r i a l p a r t ) . Treatments 3,4,5, & 6 were added i n a proportion of aproximately 2kg/m . Figure 6 shows that a l l plots with water hyacinth exhibited a higher crop y i e l d than the other treatments. This was mainly due to: 1) improvement of the s o i l texture; 2) a decreased i n the s a l i n i t y of the s o i l due to a reduced water evaporation and s a l t deposition on the s o i l surface. Leaves and whole plants added to the s o i l caused the greatest i n h i b i t i o n s to weeds i n turnip, radish, and cabbage plots (Figure 7). This effect might be due to: 1) a selective a l l e l o p a t h i c effect of water hyacinth and vegetables upon weeds, and/or 2) competition with crops. Water hyacinth has been widely used as a f e r t i l i z e r i n the chinampas because i t improves the physical and chemical properties of s o i l and i t exerts a certain control of weeds through itsdecomposition i n the s o i l . 2

2

Studies on Crop-Weed Relationships As p a r t of the Program of Agroecosystems from INIREB

(Instituto


9.

ANAYA ET AL.

Allelopathy

in

97

Mexico

-Bidens pilosa

j

j _ Mimosa pudica_|


60-Γ-

c o

50—

5 .c c

40—

'S

30— 20— 10 — 0 — 1

10- 1

stem

root Figure

3.

2

E f f e c t o f the aqueous e x t r a c t s o f s o i l s o f the shrubs s t r a t u m ( c o f f e e ) on weed growth. ( 1 ) S o i l o f Typica c o f f e e . ( 2 ) S o i l o f Bourbon c o f f e e .

too

100

50

50

ο 3*

3

7

4

TREES 1 2 3 4 5 Figure

. . . .

4.

Inga v e r a Inga j i n i c u i l Inga l e p t o l o b a Grevillea robusta L e u c a e n a pulverulenta

JZL 8

COFFEE 6 7 8 9

. . .

10

11

JO

HERBS

10 . Typica 11 . P. Bourbon Mundo Novo Ca t u r r a

aquilinum

E f f e c t o f the aqueous e x t r a c t s of d r y l e a v e s o f t r e e s , c o f f e e and herbs on the g e r m i n a t i o n and growth o f Rumex sp. (· non s i g n i f i c a n t ) .


98

ALLELOCHEMIC ALS: ROLE IN AGRICULTURE AND FORESTRY -r-100

100-r

504-

δ

8

I Downloaded by UNIV OF SOUTHERN CALIFORNIA on August 12, 2013 | http://pubs.acs.org Publication Date: January 8, 1987 | doi: 10.1021/bk-1987-0330.ch009

i ο

.Turnip

l_Mimosa pudica_l

I

I

Beans_ leaves IZ! roots I.

flowers & F i g u r e 5.

E f f e c t o f aqueous l e a c h a t e s o f Eichomia orassipes ( l e a v e s , r o o t s and f l o w e r s ) on t h e g e r m i n a t i o n and growth o f t h r e e s p e c i e s ( · non s i g n i f i c a n t ) .

^Control ESZÎ Inorganic f e r t i l i z e r f v T l Manure K-ggE-3 Water hyacinth (whole plant) recai Water hyacinth (rhizome and root) ggggj Water hyacinth ( l e a f and bulb)

TREATMENTS Figure 6.

Y i e l d of t u r n i p , r a d i s h , l e t t u c e and cabbage w i t h t h e s i x t r e a t m e n t s ( · non s i g n i f i c a n t ) .



ANAYA ET AL.

Figure

7.

Allelopathy

in

Mexico

Y i e l d and d i v e r s i t y of weeds w i t h ( · non s i g n i f i c a n t ) .

the s i x

treatments



100


Nacional de Investigaciones sobre Recursos B i o t i c o s ) , we conducted a study of the relationships between cultivated plants and weeds i n a "chinampa" at San Andres Mixquic, D.F., i n the southeastern Valley of Mexico. In t h i s study i t was found that leachates from c u l t i v a t e d plants (corn, squash, and beans) stimulated the growth of their own seedlings and inhibited that of weeds. Also, we found that corn production i s less affected by the presence of weeds when i t i s associated with Cucurbita f i c i f o l i a (Jimenez et a l . , i n preparation). F i n a l l y , i t was demonstrated that corn pollen has a strong a l l e l o p a t h i c p o t e n t i a l . These results led us to the study of several organic extracts of such pollen tested upon Cassia jalapensis. The hexanic and methanolic f r a c tion proved to be very i n h i b i t o r y to Cassia jalapensis seedlings(22)and the ethanolic extract was found to act as an i n h i b i t o r of electron transport i n isolated mitochondria from watermelon seedlings (Cruz,R., i n preparation). Studies on H e l i e t t a p a r v i f o l i a . In the northern arid region of Mexico, Rovalo e_t a l . (23) carried out a study of the p o t e n t i a l uses of H e l i e t t a p a r v i f o l i a . They demonstrated that the e s s e n t i a l o i l of H e l i e t t a acts as a fungicide upon Pénicillium, Rhizopus, Fusarium, and Aspergillus and also acts as an i n s e c t i c i d e upon Anastrepha ludens ( f r u i t f l y ) . The a l l e l o p a t h i c potential of H e l i e t t a leaves was demonstrated upon a common weed: Convolvulus arvense. Studies on Piqueria t r i n e r v i a . A very i n t e r e s t i n g study i s that of the a l l e l o p a t h i c p o t e n t i a l of Piqueria t r i n e r v i a and i t s piquerols A and B, by Gonzalez de l a Parra et a l . (14). It was found that this widely d i s t r i b u t e d weed i n the Valley of Mexico has a wide b i o l o g i c a l a c t i v i t y upon other plants. Present studies i n warm and temperate region. At present, we are assessing the a l l e l o p a t h i c p o t e n t i a l of weeds from a t r o p i c a l region of the country (Uxpanapa, Veracruz), as a complement to the project e n t i t l e d Recovery of Tropical Rain Forests from INIREB. This information i s necessary to permit more e f f i c i e n t a g r i c u l t u r a l and forest management of the secondary vegetation i n the t r o p i c s . At the same time we are studying the a l l e l o p a t h i c interactions among crops, weeds, and microorganisms and some aspects of the t r a d i t i o n a l agroecosystems known as "camellones" i n Tlaxcala, a central state i n Mexico. Those are distinguished by their b i o l o g i c a l d i v e r s i ty, the presence of water channels along the border of the crop lands, and the t r a d i t i o n a l management system, which involves b i o l o g i c a l cont r o l of pests and the use of green manure i n mono cultures of corn and i n mixed c u l t i v a t i o n with beans and squash. Our f i n a l goal i s to help generate a multiple model of production and to maintain our natural resources.

Literature Cited 1. Gómez-Pompa, Α. ; Anaya, A.L. ; Golley, F. ; Hartshorn, G. ; Janzen, D. ; Kellman, M. ; Nevling, L. ; Penalosa, J. ; Richards, P. ; Vazquez, C. ; Zinke, P. ; Guevara, S. ; In "Fragile Ecosystems" ; Farnsworth, E.G. ; Golley, F.B., Eds. ; Springer-Verlag ; New York, Heidelberg, Berlin, 1974 ; pp. 113-138. 2. Gómez-Pompa, A. ; Vázquez-Yañes, C. ; Amo R., S. del ; Butanda, Α., Eds. ; "Regeneración de Selvas" ; Cia. Editorial Continental, S.A. México, 1976. In Allelochemicals: Role in Agriculture and Forestry; Waller, G.; ACS Symposium Series; American Chemical Society: Washington, DC, 1987.


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Allelochemicals: Role in Agriculture and Forestry - American Chemical

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