Flowers have great value in the life of human beings. In the past few years, the ornamental flower industry has grown all over the world. The increase in ornamental plants was 148.2% between 1999 to 2013.
Hafiz Muhammad Bilala*, Nawal Saeedb
aCollege of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, CHINA
bCollege of Food Science and Technology, Huazhong Agricultural University, Wuhan, CHINA
In 2014, the Brazilian ornamental plants and flowers industry gives more than $5.4 billion in revenue, in this revenue potted plants and flowers showed up to 60%. Roses have more importance among all the flowers because of their variant colors, nice fragrance, and attractiveness. Roses are of great economic importance because they give the excellent material for by-products of agro-industrial goods viz. cosmetic, scent industry, and have a more significant role in nutrition and medicine. Roses are known as the queen of flowers but as cut flowers in vases, they have a short life span.
In the global ornamental floriculture sector rose flower is known as number one for cut flower purpose. Rose flower gives us visual satisfaction and it is a source and symbol of sensuality, motivation, elegance, spirituality, and friendliness. Roses are cultivated all over the world and they were grown since ancient times, roses are one of the best ancient decorating flowers for the garden.
Roses are more important for the trade purpose as cut flowers and have much importance in the landscape world for beautification, recreation, and for the lovely human being because of its sweet fragrance, variant elegance, and prettiness. Now a day’s demand of roses is high in international as well as in domestic markets for trade purposes due to its good quality and successful production of flowers. Roses are more resistant than other flowering plants against urban pollutant, soil drought, cold, dirt soil and different kind of diseases. Roses are more useful due to its resistance against severe environmental factors and can be used in wide range of green urban areas having natural environment and also can tolerate the urban polluted soil. For the best growth and optimum flower production of roses, they require complete balanced nutrition from fertilizer application just like other perennial flowering plants.
There are many factors like abiotic stresses which are responsible for the extreme decrease in the agriculture based cultivation production which leads to the estimated loss about US $100 billion yearly. Abiotic stresses from which drought, cold, and salt stresses are the main three factors mostly involved in the decrease in the quality and growth of crop cultivation.
The chemical which is mostly causes the salt stress in plants is NaCl. The changes in plants like development changes are due to different aspects of stresses in which salt stress causes the huge change in morphological, physiological and changes in the development of rose plant. The high concentration of salt causes the severe effect on the leaf area, dry weight and on the physical appearances for the vegetative growth. Some more characters are affected with the high salinity, and these characters are total chlorophyll content, proline content and total soluble sugar. In this matter, most of the scientists and researchers found that salt stress have major effect to decrease chlorophyll content of plants. If the rose plants applied with salinity level of 2–3 dS m-1, the yield of flowers and plants growth decreased by 25-50%, this bad performance against salinity proves roses as low salinity tolerance.
Plants growth and development are restrained badly through salt stress and establish different effects on plants mainly on biochemical reactions and different physiological factors like stability of mineral nutrients, photosynthesis, antioxidant uptake hormonal signaling and osmolytes buildup.
This problem of salt stress generally take place in the semi-arid and arid areas, but the other main source of increasing salinity level is human being itself. Overall, if plants are treated with 50 mM dose of NaCl or less than 50 mM it will only encourages the osmotic stress. And if the dose applied with amount of 50 to 100 mM it will cause the effect between osmotic pressure and salinity shock. The concentration about 100 to 150 mM it will induce the osmotic shock. As a result, the effect due to these stresses salinity shock and salinity stress initiate some complex changes at cellular, molecular and physiological stages.
Rose plant shows the different influences against salinity which mostly depends on substance type, plants farming system (hydroponic or soil), kind and amount of salt, rose cultivar/species, type of rootstock and the irrigation system. Thus, it is necessary to aware about the ecology and the traditional practices for cultivation of plants to discover the plants which shows more tolerance against salinity. Usually, with the increasing concentration there is negative effect of salt stress on the flowering quality and the growth of rose plant, due to which in several species of rose visual damage occur and also there is increase in quality lose. Salinity causes water absorption of plants and it leads the plant to different negative effects on metabolic processes in the plants which are directly related to water stress. Moreover, if the saline conditions increases it will decrease the plant water potential, water contents of leaves and dry matter of plants.
Few numbers of genes of rose plants have been discovered which shows the resistance against saline environment. A small protein RcHSP17.8 against heat shock discovered in cytosolic class in the Rosa chinensis, And the functions of this protein has been characterized and isolated. This discovered gene was produced in saline environment and salinity stress conditions, also in osmotic stress, oxidative stress, drought and cold. The ability of plant roots up-taking the water from the soil is reduced by salt stress. If the concentration of salt in the soil is high. And due to this process physiological drought will established because of reduction in water content inside the cell, decrease in photosynthetic function and closure. A trial was planned with the aims; to establish some suitable level of salinity which gave the good quality flowers of rose and to investigate the morph physiological adaptability of roses at different salinity levels.