Treatment and/or prophylaxis of storage diseases of harvested material

Abstract

The present invention relates to the treatment and/or prophylaxis of storage diseases of harvested material. This object is achieved by the use of the bacterium of Pseudomonas sp. Proradix (DSMZ 13134). This object is further achieved by a method comprising provision of harvested material, contacting said harvested material with a solution containing the bacterium of Pseudomonas sp. Proradix (DSMZ 13134), and storing the harvested material outside of the ground soil.

Claims

1. A method for reducing growth of Helminthosporium solani (silver scurf) on harvested tubers of a potato plant (Solanum tuberosum), comprising the following steps: a) providing harvested tubers of a potato plant (Solanum tuberosum), wherein said harvested tubers are infected with Helminthosporium solani (silver scurf), b) contacting said harvested tubers with a solution containing Pseudomonas proradix strain DSMZ 13134 as the sole active agent, and c) storing said harvested tubers outside of a ground soil under atmospheric pressure in a storage room for the purpose of later consumption.

2. The method of claim 1, comprising before step a) the following steps: a) providing tubers of the potato plant (Solanum tuberosum), a) contacting said tubers with a solution containing Pseudomonas proradix strain DSMZ 13134, a) introducing said tubers into the ground soil, a) cultivating said tubers in the ground soil, and a) harvesting the cultivated tubers to produce a harvested material, wherein said harvested material is said harvested tubers.

3. The method of claim 1, wherein in step b) the solution is applied by mordanting, spraying or immersing the harvested tubers.

4. The method of claim 2, wherein in step a) and step b) the solution is applied by mordanting, spraying or immersing the tubers.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows the effect of Proradix on the affection of potato tubers by silver scurf after the storage following a treatment of the potato tuber at the laying and/or before the storage (field trial 2010/2011 in Germany);

(2) FIG. 2 shows the effect of Proradix in comparison to the chemical of Imazalil on the regeneration of spores of the silver scurf pathogen on the potato tuber after the storage following a treatment of the potato tuber at the laying and/or before the storage (field trial 2010/2011 in the Netherlands);

(3) FIG. 3 shows the effect of Proradix in comparison to the chemical of Imazalil on the rate of germination of the spores of the silver scurf pathogen on the potato tuber after the storage following a treatment of the potato tuber at the laying and/or before the storage (field trial 2010/2011 in the Netherlands);

(4) FIG. 4 shows the effect of Proradix on the affection by the silver scurf on potato tubers after the storage following a treatment of the potato tuber at the laying and before the storage (field trial 2009/2010 in the Netherlands);

(5) FIG. 5 shows the effect of Proradix in combination with the chemical of Imazalil on the affection by the silver scurf of potato tubers after the storage following a treatment of the potato tuber at the laying and/or before the storage.

EXAMPLES

Example 1

Isolation of Proradix

(6) The isolation of the bacterium of Pseudomonas sp. Proradix is extensively described in WO01/40441, there example 1. It is explicitly referred thereto and such disclosure is made a disclosure of the present application. The bacterium is also purchasable from the company of Sourcon Padena GmbH & Co. KG, Tbingen, Germany.

Example 2

Dosage and Application

(7) For the treatment of the seed potato at or before the laying into the ground soil Proradix is used as a liquid mordant [Proradix WG (LF 4816-00); Sourcon Padena GmbH & Co. KG, Tbingen, Germany], according to the information of the manufacturer in a concentration of 60 g/ha via the spraying method by using a ULV spraying device. Before the storage of the potatoes 20 g of Proradix WG is dissolved in a maximum of 2 l of water per barrel. The application onto the potatoes is also effected by means of a ULV spraying device.

Example 3

Field Trials

(8) The laying of the potato and, if applicable, the treatment with Proradix and/or Imazalil is carried out in springtime and the harvest and storage and, if applicable, the treatment with Proradix and/or Imazalil is carried out in fall of the same year.

(9) In a field trial conducted in the years of 2010/2011 in Germany according to the EPPO guidelines the effect of Proradix was examined on an affection by the silver scurf of the potato tuber after storing in the storage facility. For this purpose, a part of the potato tubers was remained entirely untreated, another part was only treated at the laying, and yet another part only before the storage, and a further part both at the laying and also before the storage. After a storage time of 20 weeks the potatoes were examined for an affection by the silver scurf. The result is shown in FIG. 1.

(10) It is shown that more than 50% of the surface of the untreated potatoes is affected by silver scurf after the storage (FIG. 1, first column). Following a treatment of the potatoes with Proradix exclusively at the laying an affection by silver scurf after the storage can be seen, which is reduced by about 25% (absolute: 39.1%; FIG. 1, second column). Following a treatment of the potatoes with Proradix exclusively before the storage a reduction of the affection by silver scurf of almost 50% can already be seen (absolute: 26.6%; FIG. 1, third column). After a treatment of the potatoes with Proradix both at the laying and also before the storage in comparison to the untreated potatoes a dramatic reduction of the affection by silver scurf after the storage of more than 70% can be seen (absolute: 14.8%, FIG. 1; fourth column) which implies a synergistic effect (FIG. 1; cf. fourth with second and third column).

(11) In a further field trial conducted in the years of 2010/2011 in the Netherlands according to the EPPO guidelines the influence of Proradix in comparison to the chemical standard of Imazalil on the production of spores of the fungal pathogen of Helminthosporium solani, the initiator of the silver scurf, and the rate of germination of the spores on the potato tuber was examined. The results are shown in FIGS. 2 and 3.

(12) It is clearly shown that by the treatment of the potato with Proradix before the storage a dramatic reduction of the formation of spores is achieved (FIG. 2; second column) which is comparable to that being achieved by the chemical of Imazalil (FIG. 2; third column).

(13) The examination of the formation of spores shows that expecially the combined application of Proradix at the laying but also before the storage of the potatoes, in comparison to untreated potatoes, only a quarter of the formed spores is able to germinate (FIG. 3; second column). Here Proradix shows significant advantages over the chemical of Imazalil, the use of which still enables half of the spores to germinate (FIG. 3; fourth column).

(14) In another field trial which was conducted in the years of 2009 and 2010 in Germany according to the EPPO guidelines the results shown in FIG. 1 were confirmed. The result of this field trial is shown in FIG. 4.

(15) In a field trial conducted in the years of 2010 and 2011 in Germany according to the EPPO guidelines it was examined in detail, whether Proradix can also be effectively used in combination with the chemical of Imazalil. For this purpose a part of the potatoes remain untreated, a part was treated with the chemical of Imazalil at the laying, and a part was treated at the laying and also before the storage with the chemical of Imazalil, and yet another part was treated at the laying with Imazalil and before the storage with Proradix. The result is shown in FIG. 5.

(16) It becomes apparent that, in comparison to untreated potatoes, the application of Imazalil at the laying in combination with the application of Proradix before the storage results in a dramatic reduction of an affection by silver scurf after the storage (FIG. 5; cf. fourth with first column), whereas a treatment of the potatoes exclusively with Imazalil at the laying and the storage results in a significantly diminished reduction of the affection by silver scurf after the storage (FIG. 5; cf. third with first column).

CONCLUSION

(17) The inventors were able to demonstrate, using the example of the potato and the silver scurf, that the Pseudomonas strain of Proradix can be employed for the treatment and/or prophylaxis of storage diseases of harvested material. The protective effects of the Pseudomonas strain of Proradix were so far only described in cases where the bacterium was introduced into the ground soil and given to the root and, therefore, into its natural habitat. As a consequence, the Pseudomonas strain of Proradix used as a biological storage mordant is a particular environment-friendly alternative to the chemicals which are so far used.