DESCRIPTION

"USE AS A FERTILIZER OF A PLANT EXTRACT OBTAINED FROM GOLF COURSE AND LAWN MAINTENANCE"

Technical Field of the Invention

This invention is based on the use of a plant extract, which is obtained from the management of lawn turf grasses, in the manufacturing of fertilizers.

Prior Art

At present, the reuse of grass clippings is limited to composting and mulching (S. I. C. F.A., 1990), aiming at the improvement of physical soil properties, a technique that does not have any industrial application.

However, macerating fresh grass clippings in water can result in a new plant extract which can be used in the manufacturing of fertilizers to correct plant nutritional deficiencies, namely iron (Fe) deficiency.

Iron deficiency, normally described as iron chlorosis, affects several agronomic crops, in particular tree crops, and occurs mainly in calcareous soils of arid and semi -arid regions, being common in Mediterranean countries (Chen and Barak, 1982) .

This nutritional imbalance affects yield and fruit quality, and it is necessary to apply massive amounts of synthetic iron chelates to soils, like EDDHA (Pestana et al . , 2003). Due to the fast iron immobilization in calcareous soils, these applications must be repeated each year. The costs of iron chlorosis correction are very high and can represent 60% of the total fertilization inputs (Tagliavini and Rombola, 2001) .

In addition, the environmental impacts of these applications are unknown. We do know, however, that synthetic chelates can be responsible for enhanced plant uptake of metals, such as manganese, copper and nickel (Wallace and Wallace, 1992) .

In order to develop alternative practices of iron correction associated with the use of smaller amounts of fertilizers, several studies have been conducted to test foliar and soil application of new products (Erdal et al . ,

2004; Pestana et al . , 2003; Pestana et al . , 2004).

Foliar sprays can act directly, through Fe supply (Erdal et al . , 2004) and/or indirectly, on the apoplastic and cell membrane pH levels. However, these treatments are effective only in moderate symptoms of iron chlorosis, and are limited by the short duration of the recovery of the symptoms (Rombola et al . , 1999).

The success of foliar sprays with iron compounds depends on their capacity to penetrate the cuticle, travel through the apoplastic free space and cross the plasmalemma of leaf cells to reach the cytoplasm (Rombola et al . , 2000) .

Several authors (Marino et al . , 2004; Rombola et al . , 2001) have used plant extracts obtained from marine algae and/or spontaneous shrubs to correct iron chlorosis. However, in spite of some positive results, the application of these products is not suitable on an industrial scale due to the shortage of raw material and the need to include Fe compounds .

Besides, the use of this green residue is very attractive since it can be rapidly obtained without the use of specific and heavy equipment. This is more advantageous than the method and apparatus for field processing alfafa to obtain a fibrous fraction and liquid fraction which is applied onto the field during processing (USA patent

4109448 (Kline) ; 1978) .

Brief Description of the Drawings

Figure 1 shows a scheme concerning the process, according to the invention, to obtain the plant extract.

Figure 2 shows that application of this extract increases the low values of leaf chlorophyll in mature and young leaves.

- A -

Stunmary of the Invention

Currently, greenkeepers pay large amounts of money to remove fresh residues (grass clippings) resulting from the management of lawn turf grasses .

This invention will allow the use of a plant extract, obtained from grass clippings, as a raw material for the fertilizer industry, therefore enhancing several economic sectors .

This plant extract is obtained from grass clippings as a result of the management of lawn turf grasses and golf courses in the Algarve and it is used to recover from iron chlorosis in strawberries. The extract is obtained by macerating fresh grass clippings in distilled water (1:10) , without any composting process. The use of this green residue is very attractive since it can be rapidly obtained without the use of specific equipment.

This invention allows the use of this extract to be expanded to other crop species and other plant nutrients .

Detailed Description of the Invention

This invention results from the resolution of two problems: i) the accumulation of large amounts of plant

residues obtained from the management of lawn turf grasses and golf courses and ii) the need to establish alternative methods to correct iron chlorosis in agronomic crops, without negative environmental and economic impacts.

Currently, greenkeepers pay large amounts of money to specialized companies to remove fresh residues

(grass clippings) resulting from the management of lawn turf grasses. With this invention, fertilizer industries will use this plant extract as the main raw material to produce a new line of biofertilizers .

This invention allows the reduction of negative environmental impacts, and avoids the use of synthetic chelates, a normal procedure used in tree orchards established on calcareous soils or presenting iron deficiencies .

This plant extract is obtained from grass clippings as a result of the management of lawn turf grasses and golf courses in the Algarve, and it can be used to recover from iron chlorosis for example in strawberries. The extract is obtained by macerating fresh grass clippings in distilled water (1:10), without any composting process.

The use of this green residue is very attractive since it can be rapidly obtained at room temperature (around 20 °C) without the use of any specific equipment.

However, fermentation can be used to increase the content of compounds existing in this plant extract with fertilizing properties. After extract preparation, the fermentation process can be conducted during 24 hours at 30 ⁰ C.

It is possible to use this extract to fertilize other crop species, with special emphasis on tree crops.

The fertilizing capacity of this extract regarding other nutrients can also been considered.

This invention will allow the use of a plant extract, obtained from grass clippings, as a raw material for the fertilizer industry, therefore promoting several economic sectors .

Grass clippings are a residue resulting from the management of lawn turf grasses and golf courses in the Algarve, and other regions. Greenkeepers pay specialized companies to remove this residue, currently without any industrial application, in order to avoid the accumulation of large quantities thereof.

In addition, the use of synthetic iron chelates is common practice in the case of trees, such as citrus, grown on calcareous soils or with iron deficiencies, which can have a negative environmental impact .

Therefore, with this invention we seek to solve

two problems: i) the accumulation of large amounts of plant residues obtained from the management of lawn turf grasses and golf courses and ii) the need to establish alternative methods to correct iron chlorosis in agronomic crops, without negative environmental and economic impacts.

This invention can be used to prepare a plant extract obtained from grass clippings (turf grass extract) .

Clippings from three grass species, Lolium perene

L. (60%) , Festuca spp . (20%) and Poa partensis L. (20%) , with a length of 1-2 mm are removed from a tee area of a golf course located in the Algarve (southern Portugal) , and are rapidly transported to the laboratory in a refrigerator bag (around 4°C) . The extract is obtained by macerating 100 g of grass clippings (fresh weight) in 1 litre of distilled water, and the macerate is then filtered twice through a 1- mm sieve.

In Figure 1 the process to obtain this plant extract, which is frozen at -20 °C until use, is shown. The mineral composition of the extract and the electrical conductivity (EC) values are shown in Table 1. This extract has a neutral pH and low EC values (1.20 dS πf ¹ ) . Regarding nutritional content and as compared to crop needs, the concentration of Mg and Ca is very low, with the exception of Zn. Using fermentation processes, it is possible to enhance nutrient and other compound availability, which have particular agronomic importance.

Table 1

Parameters Average values pH 6.38

EC (dS m ^"1 ) 1.20

Nutrients (mg kg ^"1 ) :

Mg 0.64 + 0.01

Ca 4.02 + 0.33

Fe 3.86 ± 1.17

Cu 2.98 ± 0.48

Mn 7.24 ± 0.33

Zn 15.30 ± 0.12

The foliar application of grass clipping extract allows the correction of iron deficiency in strawberry plants .

The initial recovery of iron chlorosis symptoms is possible after just two applications of grass clipping extract, but total recovery is only possible after four sprays. Total leaf chlorophyll allows the evaluation of both the degree of chlorosis and the intensity of the iron deficiency. The application of this extract increases the low values of leaf chlorophyll (which is a characteristic of iron deficient plants) . This increase is presented in

Figure 2 and is 5 times higher in young leaves. Thus, iron deficient plants treated with this extract show chlorophyll

values similar to those of control plants (completely green) .

The application of this extract also has positive effects on root enzyme activity, yield and fruit quality.

Also, the soil application of this extract, as a product without negative environment impact, is an alternative to foliar spray.

Thus, fertilizer manufacturing companies can use this plant residue (grass clippings) as a main raw material for the launching of new biofertilizer product lines.

In complement but not limiting the claims of the present invention, two field trials are described below.

Example 1

In order to simulate industrial process, fertilizers were prepared at room temperature (around 20 ⁰ C) by adding 15 g of iron sulphate (FeSO ₄ .7H ₂ O) to 88 g of grass clippings extracts (fermented and non-fermented) . A commercial preservative called Nipazol was added (4 g L ^"1 ) in order to stop the extracts fermentation.

At least, three citrus trees established on calcareous soils, showing moderate symptoms of iron

chlorosis, were pulverized with each of these fertilisers in a rate of 2 L tree ^"1 each fifteen days from July to September (total of 5 sprays) . At the end, trees were recovered from symptoms and chlorophyll values increase 25% from the initial values.

Example 2

Additionally, in order to test the efficacy of the grass clipping extracts as stimulating growth compounds, two extracts were prepared at room temperature

(around 20 ⁰ C) : i) fermented grass clippings extract and ii) non-fermented grass clippings extract. Nipazol, a commercial preservative , was used as adjuvant (4g L ^"1 ) in order to stop the fermentation process of both extracts. To test the agronomical effect, a foliar fertilization was done three times at a total dosage of 12 L ha ^"1 , diluted 100 times, during the growth season in two well-fertilised crops: industry tomatoes (vegetative growth, first blooming and fructification stages) and potatoes (tuber initiation, two weeks after tuber initiation, two weeks after previous foliar application) . So, contrary to example 1, the extracts were tested in plants without symptoms of nutrients deficiencies. Extracts foliar application resulted in yield increments up to 11% compared to untreated control plants.

References

Chen, Y. and P. Barak. 1982. Iron nutrition of plants in calcareous soils. Advances in Agronomy, 35: 217-240. Erdal, I., K. Kepnek, and I. Kizilgδz. 2004. Effect of foliar applications at different growth stages on iron and some nutrient concentrations in strawberry cultivars. Turkish Journal of Agriculture and Forestry, 28:421-427. Marino, G., M. Hernandez, A. Lucci, and A. D. Rombola. 2004. Responses of in vitro cultured kiwifruit shoots to treatments with green amaranth aqueous extracts. Journal of Horticultural Science & Biotechnology, 79 : 759-763. Pestana, M., A. de Varennes, and E.A. Faria. 2003.

Diagnosis and correction of iron chlorosis in fruit trees: a review. Food, Agriculture & Environment, 1:

46-51.

Pestana, M., A. de Varennes, and E.A. Faria. 2004. Lime- induced iron chlorosis in fruit trees., p. 171-215. In: R. Dris and S. M. Jain (eds.). Production practices and quality assessment of food crops. Volume 2: Plant mineral nutrition and pesticide management. Kluwer Academic Publishers, Dordrecht, The Netherlands. Rombola, A. D., W. Brύggemann, M. Tagliavini, B. Marangoni , and P. R. Moog. 2000. Iron source affects Fe reduction and re-greening of kiwifruit (Actinxdea deliclosa) leaves. Journal of Plant Nutrition, 23: 1751-1765.

Rombola, A. D., F. Mazzanti, G. Sorrenti, G. Perazzolo, M.

Caravita, R. Raimondi, and B. Marangoni . 2001. Use of plant water extracts for the controls of Fe chlorosis in fruit trees: a preliminary report, p. 81. Book of Abstracts of International Symposiun on Foliar

Nutrition of Perennial Fruit Plants, Merano, Italy. Rombola, A. D., M. Quartieri, B. Marangoni, M. Tagliavini,

D. Scudellari, and J. Abadia. 1999. Strategie di cura della clorosi ferrica nella fruticoltura integrata. Frutticoltura, 5: 59-64.

S. I. C. F.A. 1990. (Soil Improvement Committee California

Fertilizer Association) . Western Fertilizer Handbook.

Interstate Publishers, Inc., Banville, Illinois. Tagliavini, M. and A. D. Rombola. 2001. Iron deficiency and chlorosis in orchard and vineyard ecosystems. European

Journal of Agronomy, 15: 71-92. US patent 4,109,448 - D. C. Kline. 1978. Method and apparatus for in-field processing of vegetation. Wallace, A. and G.A. Wallace. 1992. Some of the problems concerning iron nutrition of plants after four decades of synthetic chelating agents. Journal of Plant

Nutrition, 15: 1487-1508.