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H. Review of Related Literature

Strawberries are a viable crop in most areas of the United States. Cultivars have been developed to suit most agro-climatic conditions. In many locations, demand for locally produced berries far exceeds available supplies; small-scale producers can thus get higher returns from strawberries than from most other crops.
( http://attra.ncat.org/attra-pub/strawberry.html)


Strawberries are small-fruit crops that lend themselves well to small-scale and part-time farming operations. Initial investment is high but is primarily related to the cost of land preparation, planting, and installing an irrigation system. Also, equipment needs on a small-acreage farm are not very great. Strawberry plantings should produce commercialquality fruit for three to five years. Increasing demand for strawberries in recent years has kept fresh-market prices relatively stable. Growing strawberries is not for everyone however, as they have special production requirements, as well as a short shelf life and marketing season. (http://pubs.cas.psu.edu/FreePubs/pdfs/ua290.pdf)

Cacti, cultivated by people worldwide, are a familiar sight as potted plants, houseplants or in ornamental gardens in warmer climates. They often form part of xeriphytic (dry) gardens in arid regions, or raised rockeries. Some countries, such as Australia, have water restrictions in many cities, so drought-resistant plants are increasing in popularity. Numerous species have entered widespread cultivation, including members of Echinopsis, Mammillaria and Cereus among others. Some, such as the Golden Barrel dekha Cactus, Echinocactus grusonii, are prominent in garden design.
Cacti are commonly used for fencing material where there is a lack of either natural resources or financial means to construct a permanent fence. This is often seen in arid and warm climates, such as the Masai Mara in Kenya. This is known as a cactus fence. Cactus fences are often used by homeowners and landscape architects for home security purposes. The sharp thorns of the cactus deter unauthorized persons from entering private properties, and may prevent break-ins if planted under windows and near drainpipes. The aesthetic characteristics of some species, in conjunction with their home security qualities, makes them a considerable alternative to artificial fences and walls.( http://en.wikipedia.org/wiki/Cactus).
Opuntia ficus indica (L.) Miller is a cactus species widely utilized in semi-arid zones as a fruit and forage crop. It is one of the few crops that can be cultivated in areas which offer little growth possibility for common fruits and vegetables.
Nutritive value of its fruits (prickly pear) and cladodes continues to be studied in attempt to better use this species. Research studies related to the histological and physiological aspects of the growth and adaptation of Opuntia ficus indica to drought were carried out by several authors.
In Tiznit (south Morocco), Opuntia ficus indica species is represented essentially by two ecotypes called 'Aissa' and 'Moussa'. They could be distinguished by the flowering time and the period of fruit maturation which is respectively June to August and September to December. In addition, the presence and absence of spines on cladodes is a frequently used character in the ecotype identification. However, the expression of such characters could be more or less influenced by the environmental conditions. At actual time there is no marker-assisted breeding program for Opuntia ficus indica. (http://bbplaboratory.ifrance.com/opuntia.html)

Food spoilage may be defined as any change that renders food unfit for human consumption. These changes may be caused by various factors, including contamination by microorganisms, infestation by insects, or degradation by endogenous enzymes. (http://www.britannica.com/EBchecked/topic/560730/spoilage)
The heat resistance of endo-polygalacturonase (endo-PG) of the strawberry spoilage fungi, Rhizopus sexualis, R. stolonifer and Mucor piriformis, was compared to that of isolates of R. arrhizus, R. stolonifer and R. oryzae known to cause breakdown of canned apricots. All species produced endo-PGs in culture medium which showed marked heat tolerance and a bimodal heat stability. Heating for 10 min at temperatures between 30-120°C indicated that maximum inactivation occurred at 50-60°C. Stability increased from 70°C to 100°C and then declined, but in some cases activity remained even after heating at 120°C for 10 min. Similar trends in heat resistance were recorded for endo-PGs in infected tissue of apricot, peach, tomato and cherry fruits, whereas those in infected tissue of strawberry, raspberry and plum were rapidly inactivated at all temperatures above 40°C. The possible reasons for differences between fruits are discussed. (http://www3.interscience.wiley.com/journal/113323635/abstract)