(1) Field of the Invention
The present invention relates to a device which releases a development affecting gas for affecting the development of plant materials and to a method for use of the device. In particular, the present invention relates to a method for initiating ripening or retarding ripening of a fruit or vegetable, particularly with ethylene.
(2) Description of Related Art
Ethylene and other growth affecting gases have been used in storage rooms to modify the natural growth rate of plant materials including whole plants and plant parts such as fruits and vegetables. Such storage room systems are described in U.S. Pat. Nos. 3,620,765 to McDonnell et al; 3,924,010 to Erb; Re 28,995 to Burg. and 4,764,389 to LaBarge. These systems can only be used by wholesalers and others dealing in bulk fruits and vegetables.
The prior art has described various forms of packaging to inhibit or accelerate growth of fruits or vegetables. U.S. Pat. Nos. 3,069,274 to Concannon; 3,798,333 to Cummin; 4,528,228 to Clevenger and 4,622,229 to Toshitsugu are illustrative of such packaging. The common concept is the provision of a gas to facilitate ripening or the removal of a gas (ethylene) by the package to retard ripening of the fruit or vegetable. Such packaging can be expensive and the effect on development is subject to variation depending upon the handling and storage of the fruit or vegetable.
The prior art has described the treatment of plants to prevent fungal or other microorganism infection of cut or exposed portions. Illustrative is U.S. Pat. No. 2,923,632 to Castberg. Such treatments can only be used where the portion of the plant being treated is not eaten. Further, unless the fungicide or other chemical is safe for food purposes, it is difficult to obtain approval to market such devices. In any event, such devices are not used to affect the development (ripening or retarded ripening) of the plant material.
The prior art has described numerous chemicals for producing ripening in the manner of ethylene. They are particularly set forth by Kays, S. and Beaudry, R. in Acta Horticulturae 201 77-115 (1987). Burg, S. et al., Plant Physiol. 42 144-152 (1987) describes various unsaturated organic compounds as substitutes for ethylene to provide ripening of fruits and vegetables. Alternatively, carbon dioxide and other carbon-oxygen gases have been used to retard ripening of fruits and vegetables.
The problem has been to provide a convenient, on demand method and means for initiating the ripening and/or retardation of ripening of the fruit or vegetable.