10-08-2021, 04:59 AM
Flowers are harvested with sharp knives or electric pruning shear. On standard carnations two to three nodes and on spray carnations three to four nodes are left on the shoots for the next flowering. Flowers should be cut in the early morning when plants are turgid. Standard carnations are harvested as open flowers or in the bud stage. Spray carnations are harvested with two flowers open and the rest showing color. Flowers are handled carefully to avoid breakage and bruising. It is important to expose flowers to a 40° to 48°F environment as soon as possible to reduce plant temperature. Precooling the flowers maintains quality and increases longevity.
Human beings disseminate all kinds of pathogens over short and long distances in a variety of ways. Within a field, humans disseminate some pathogens, such as tobacco mosaic virus, through the successive handling of diseased and healthy plants. Other pathogens are disseminated through tools, such as portable mini electric garden shears, contaminated when used on diseased plants (e.g., pear infected with fire blight bacteria), and then carried to healthy plants. Humans also disseminate pathogens by transporting contaminated soil on their feet or equipment, using contaminated containers, and using infected transplants, seed, nursery stock, and budwood as mentioned previously. Finally, humans disseminate pathogens by importing new varieties into an area that may carry pathogens that have gone undetected, by traveling throughout the world, and by importing food or other items that may carry harmful plant pathogens. Examples of the role of humans as a vector of pathogens can be seen in the introduction into the United States of the fungi causing Dutch elm disease and white pine blister rust and of the citrus canker bacterium, in the introduction in Europe of the powdery and downy mildews of grape, and, more recently, in the rapid spread of sorghum ergot almost throughout the world (Fig. 2-20).The process of harvesting in Stevia is very important to obtain the highest leaf biomass yield with the most desirable quality and quantity of the sweet compound of steviol glycosides with a desirable taste. The time to harvest Stevia crop varies dependent on the place and time. The first harvest generally can be done 4 months after cultivation and the subsequent harvest is suggested to be done once every 3 months or 40–60 days later. Generally, three commercial harvests can be done every year. Optimum biomass and steviol glycoside quality and quantity can be obtained at the stage of flower bud initiation. It is suggested to cut the branches about 5.0 cm above the ground with tree branches powered pruning shears before stripping the leaves. As the tips of the stems contain as much steviol glycoside as the leaves, they can be added to the harvest yield. It is recommended to cut the stems leaving about a 10 cm portion above the ground to induce the emergence of new flushes, for the subsequent harvest (Kassahun et al., 2013). Benhmimou et al. (2017) reported that the optimal yield depended on the harvesting time and the yield of summer harvesting (August) was higher than that of autumn harvesting (October).Pinching can be done manually or chemically, but most plants are pinched with powerful battery operated pruning shears or electric clippers. Some propagators use the pinch as a way to get cuttings so the plants serve dual roles as stock plants and eventually as flowering plants. If such a practice is followed then the pinch involves the removal of shoots about 3 to 4 inches long. If cutting production is not an objective of pinching, then only the tips of the shoots need to be removed. More leaf axils then remain, so one might expect more lateral shoots than when a harder pinch is made.A thick-bladed, moderately sharp knife can be used to cut woody substrata or dig in soil. Some collectors carry both a knife and a trowel for collecting sporocarps from soil. Different types of fungi occurring on wood require different types of collecting equipment. An ax or hatchet often is needed to extract wood to a depth sufficient to enable identification of the host if it is unknown. However, a mallet and wood chisel, a heavy sheath knife, or a folding knife with a locking blade are usually sufficient for removing the fungus. A pair of electric bypass pruning shears and a folding pruning saw are also helpful for cutting smaller diameter twigs and branches to a uniform length. Care must be used to avoid undue damage to the plant if collecting from a living tree (Figs. 8.10 and 8.11).
Human beings disseminate all kinds of pathogens over short and long distances in a variety of ways. Within a field, humans disseminate some pathogens, such as tobacco mosaic virus, through the successive handling of diseased and healthy plants. Other pathogens are disseminated through tools, such as portable mini electric garden shears, contaminated when used on diseased plants (e.g., pear infected with fire blight bacteria), and then carried to healthy plants. Humans also disseminate pathogens by transporting contaminated soil on their feet or equipment, using contaminated containers, and using infected transplants, seed, nursery stock, and budwood as mentioned previously. Finally, humans disseminate pathogens by importing new varieties into an area that may carry pathogens that have gone undetected, by traveling throughout the world, and by importing food or other items that may carry harmful plant pathogens. Examples of the role of humans as a vector of pathogens can be seen in the introduction into the United States of the fungi causing Dutch elm disease and white pine blister rust and of the citrus canker bacterium, in the introduction in Europe of the powdery and downy mildews of grape, and, more recently, in the rapid spread of sorghum ergot almost throughout the world (Fig. 2-20).The process of harvesting in Stevia is very important to obtain the highest leaf biomass yield with the most desirable quality and quantity of the sweet compound of steviol glycosides with a desirable taste. The time to harvest Stevia crop varies dependent on the place and time. The first harvest generally can be done 4 months after cultivation and the subsequent harvest is suggested to be done once every 3 months or 40–60 days later. Generally, three commercial harvests can be done every year. Optimum biomass and steviol glycoside quality and quantity can be obtained at the stage of flower bud initiation. It is suggested to cut the branches about 5.0 cm above the ground with tree branches powered pruning shears before stripping the leaves. As the tips of the stems contain as much steviol glycoside as the leaves, they can be added to the harvest yield. It is recommended to cut the stems leaving about a 10 cm portion above the ground to induce the emergence of new flushes, for the subsequent harvest (Kassahun et al., 2013). Benhmimou et al. (2017) reported that the optimal yield depended on the harvesting time and the yield of summer harvesting (August) was higher than that of autumn harvesting (October).Pinching can be done manually or chemically, but most plants are pinched with powerful battery operated pruning shears or electric clippers. Some propagators use the pinch as a way to get cuttings so the plants serve dual roles as stock plants and eventually as flowering plants. If such a practice is followed then the pinch involves the removal of shoots about 3 to 4 inches long. If cutting production is not an objective of pinching, then only the tips of the shoots need to be removed. More leaf axils then remain, so one might expect more lateral shoots than when a harder pinch is made.A thick-bladed, moderately sharp knife can be used to cut woody substrata or dig in soil. Some collectors carry both a knife and a trowel for collecting sporocarps from soil. Different types of fungi occurring on wood require different types of collecting equipment. An ax or hatchet often is needed to extract wood to a depth sufficient to enable identification of the host if it is unknown. However, a mallet and wood chisel, a heavy sheath knife, or a folding knife with a locking blade are usually sufficient for removing the fungus. A pair of electric bypass pruning shears and a folding pruning saw are also helpful for cutting smaller diameter twigs and branches to a uniform length. Care must be used to avoid undue damage to the plant if collecting from a living tree (Figs. 8.10 and 8.11).