Abstract- one of the jobs in production of Orchid is different sorts of harmful plagues. To cover with this job, an thought of utilizing electromagnetic exposure is proposed. The method is stull being tested, nevertheless current consequences shows promise.
Synergistic dealingss between assorted subdivisions of scientific discipline and engineering have improved interdisciplinary Fieldss. In fact, most of the research activities take topographic point someplace among these subdivisions. Therefore, a specializer from one subdivision normally can suggest fresh methods, whenever enters the new field, based on his old cognition. In this brief paper, a new thought from electromagnetism to be used in Orchid plague controlling is introduced. With the addition in demand for luxury flowers such as Orchids, the manufacturers are seeking to maximise addition in production. However, the plague job is still insolvable in many facets.
Traditional manufacturers used adult male easy solution to the pest control by traditional chemical sprays. Despite the simpleness of usage, these chemical insect powders have many disadvantages such as nursery have consequence [ 1 ] . Conventional heating methods in post-harvest agribusiness are impractical because of Orchids sensitiveness to temperature and the fact that this sort of warming hents ( larvae ) both pest and the flower. As a consequence, some modern techniques such as familial interventions and some other unconventional methods such as supersonic moving ridges and electromagnetic interventions have been suggested. The latter has been suggested for pest control of post-harvest stored merchandises such as rice, fruits and walnuts [ 1 ] – [ 10 ] . Recently, we suggested it for usage in forestalling the freeze of agricultural merchandises [ 11 ] . Here the thought of utilizing electromagnetic exposure to command plagues of Orchid is discussed [ 11 ] . This procedure can be based on intervention of biological organisation of plagues or to badgering those utilizing microwaves to protect the flower.
Orchids are treasured for their showy flowers that are frequently rather big and brilliantly colored. Therefore, there are many attendings to them which make them a large trade for manufacturers. Celebrated Orchids are shown in Fig. 1. In the undermentioned Sections, some of import information about Orchids is presented [ 12 ] .
( a ) Cattleya Lake Murray ( B ) Cattleya MacHolmes ( degree Celsius ) Cattleya Michael Crocker
( vitamin D ) Cattleya oconee ( vitamin E ) Cattleya S.J.Bracey ( degree Fahrenheit ) Cattleya Starting point
Fig.1: Some sorts of celebrated Orchids [ 12 ]
Orchids are usually cultivated for their flowers. There are several types of orchid with different size and colourss with the same basic construction. Figure 2 shows the three sepals in the outermost parts of an orchid. In non-orchid flowers this portion is green and helps protect the flower when it is still at its bud phase. In orchids, nevertheless, they are colored and assist to make greater colour and size. The topmost sepal in each flower, usually called the dorsal sepal, is somewhat larger than the other two. These two are positioned at each side and towards the base of the flower. The size and form of these sepals varies greatly from species to species, and industrial florist would wish to develop orchids that are larger and have more alone sepals. Besides, they have three petals and these are coloured petals. The two topmost petals, on either side of the flower, are equal in size and form. However, the lower petal is normally formed into the form of a lip and is known as the labellum. This petal is the most cosmetic and extremely formed portion of an orchid flower and often acts as a landing platform for pollenating insects. In add-on, they mimic insects in and colour and form therefore pull them to the flower.
In size, orchid flowers size scope from minute types up to 20 centimeter. Even within a genus, the forms and sizes of flowers besides vary widely. However, the constructions of all orchid flowers have the same basic signifier, irrespective of whether they are of borne on a root, such as with Pleione formosana, or in bunchs on cernuous roots separately, like those of Dendrobium densiflorum. Each flower has three petals and three sepals.
Fig.2: A diagram of the assorted parts of an Orchid
Cymbid is one the most celebrated of Orchids, therefore, the cultivation information of this orchid is presented as an illustration to others. It is brilliant orchids, with modern 1s in a broad colour scope and spikes that bear 6-20 durable flowers. A Large-flowered type ( besides known as Standard Cymbidiums ) usually blooms from early winter to late spring with flowers enduring 8-12 hebdomads. Miniature-type flower live from mid-autumn to late spring with flowers enduring 6-8 hebdomads and sometimes longer. The needed temperature is 11 to 14 & A ; deg ; C ( 52-57 & A ; deg ; F ) at dark and 16-20 & A ; deg ; C ( 61-68 & A ; deg ; F ) during the twenty-four hours.
Cymbids are sensitive to high temperatures ; hence sufficient airing is necessary. Additionally, when flower buds are developing it is indispensable that the temperature at dark falls below 15 & A ; deg ; C.
During early summer to early fall period, orchids need to be placed in moderate to good visible radiation outside or in a cool nursery. The workss could easy acclimatise to outdoor or chill nursery conditions in early summer, and easy to indoor conditions in early fall. To supply sufficient humidness around the works, one can put it on moist crushed rock. However, the base of the pot can non be invariably soaked.
Besides, when irrigating orchids to the first clip, its necessary to add a specific fertiliser. for case, when fertilisers are used overly and in strong concentrations, damage the roots of an orchid.
Pest of Orchid
Normally, several sorts of plagues attack orchids. Therefore, it is indispensable to maintain all nurseries and conservatories clean and free from rubbish and factors that might cowage pest genteelness. To command these plagues, some insect powders have been used, but it is found that they are risky to people and the environment. Some illustrations of orchid plagues are ruddy spider touchs, aphids, false spider touchs, mealy bugs, scale insects, thrips and weevils as shown in Fig. 3 severally [ 12 ] .
Red Spider Mites Aphids False Spider Mites
Mealy Bugs Scale Insects Thrips
Fig. 3: Main plagues of Orchids
Red Spider Touchs
The touchs are little insects with the size of a little dumbbell and besides slow-moving. Red spider touchs are infinitesimal, eight-legged, spider-like insects. They chiefly infest the bottoms of foliages, doing the upper surfaces to go dotted with xanthous splodges. Severe infestations are really unpleasant and foliages will frequently fall off the plane. If the job is ignored, the touchs will bring forth neting between the foliages waterless roots.
In add-on, dry ambiance encourages them where they are more baneful when workss are insufficiently watered and the compost is invariably dry. Red spider touchs are hard to eliminate one time they have become established.
Aphids or greenflies are harmful sap-sucking plagues which spread rapidly if non continued. They gather around the soft parts of shoots particularly their tips, junctions of roots and under foliages, sucking sap and doing foliages to those pickets. They are green, plump and have tiny shore wings. They secrete a substance which encourages the growing of cast.
False Spider Touchs
In recent old ages, false spider touchs have become annoying, particularly the Phalaenopsis species. They cause opposing on the upper surface of foliages which causes fungous disease if neglected. In the beginning of infestation, we use the same control measures as suggested for ruddy spider touchs. Although this harmful plague can be controlled, it causes Markss on the foliages that are repairable.
Mealy bugs are slow-moving similar to ruddy spider touchs. They are bit by bit clustered and inactive insects which resemble little woolly woodlice. They congregate around roots, leaf-joints and under foliages. They suck sap and bring forth a gluey substance which encourages the growing of dirty. Advance infestations are hard to extinguish and best treated with a systemic insect powder.
Scale insects look like a little brown phonograph record and are formed on the bottoms of foliages, particularly along the venas. They are unsightly and do light musca volitanss. They can be removed by pass overing with a moist fabric or damp cotton bud when they are still immature. Plants which are to a great extent infected may besides exhibit sooty mold. At this phase, obliteration is really hard.
Thripss are little, fast-moving and flitting, fly-like insects. They pierce the tissue and suction sap to feed and therefore do silvery mottling and prevent normal foliage and flower development. Advance phases of infestation causes stunted and horrid workss.
One of the most destructive plagues of orchids is weevils. Adult beetles are bantam, less than 12 millimeters long. They feed on foliages, chiefly at dark and the cream-colored larvae ( chow ) have brown, slightly big caputs with their oral cavity adapted to eat roots. The larvae live in the compost and hence demands to be changed when repotting to guarantee that new workss are free from these plagues. Chewed foliages are easy seen but when larvae are present, the first indicant of their presence is when the leaf wilts. They cause a terrible infestation in this phase. Puting the works under a shadiness helps their recovery.
Pest Control Using Electromagnetic Treatment
Electromagnetic moving ridges for insect control in trade goods for many old ages. Initial probes utilizing RF heating to command plagues of grain and nuts were conducted by Frings [ 13 ] , Thomas [ 14 ] and Nelson [ 15 ] . Hirose et Al. [ 16 ] studied the usage of dielectric warming ( 2450 MHz ) for commanding baccy moth larvae.
There are assorted thoughts about the mechanism of pest control utilizing electromagnetic moving ridges. Most of the research workers believe that the moving ridges can merely warm up the plagues which largely composed of H2O instead than the other stuffs in the part [ 1-9 ] , but the others say that they may hold some unknown impacts which can be utile in the intervention [ 17 ] . Below, both thoughts are evaluated, but more probes are in advancement.
To warm up a stuff remotely utilizing wireless moving ridges, the fanciful portion of the dielectric invariable can be used as mentioned in subdivision V. However, the chief end is non merely to warm a stuff ( i.e. a flower ) indoor since it can be done utilizing a warmer or 2.4 GHz microwave beginning. The mission, here, is to warm a unstable stuff without impacting the others while the other 1s are non affected. This can be done utilizing the differences between the fanciful parts of the insulator invariables which alterations versus frequence every bit good. Section V besides furbishes the theory. We believe that there is an appropriate frequence for which the energy is absorbed by the plague but non the place. So this procedure will non impact the quality of the Orchids, owing to the fact that they are sensitive to temperature addition.
On the other manus, it is said that non merely these moving ridges warm the plague, but besides they can interfere with their physiology [ 18 ] – [ 21 ] . To verify this claim, we have done some trials on Sunne plague samples which are plagues of wheat. Figure 4 ( a ) – ( B ) , represents some of our practical trials to happen suited frequences of the electromagnetic exposure. Figure 4 ( a ) shows pest running off from the aerial in some frequences. The plague ‘s escaping may be due to warming but the power is non high plenty for important temperature addition. Furthermore, we do non anticipate the moving ridges to pull plagues, but some frequence sets will make it. The thought can be extended to Orchid plagues every bit good.
( a ) Attraction ( B ) Repeling
Fig.4: Attraction and driving phenomena of plague in response to different frequences.
Dielectric stuffs, such as most workss, can hive away electrical energy and change over it to heat. Each stuff has a complex permittivity ( ? ) in general. Harmonizing to measurings this value frequence dependant. The fanciful portion ( ??? ) of this value is responsible for soaking up of electromagnetic moving ridges in each stuff. Eq. ( 1 ) shows the general signifier of the first Maxwell ‘s equation sing ( ??? ) .
( 1 )
As a effect, entire power soaking up in a specific stuff is achieved if the 2nd portion of the equation is integrated over the material volume as can be seen in Eq. ( 2 ) .
( 2 )
The basic thought is to utilize ??? to warm the selected stuffs far from electromagnetic beginning.
The addition in temperature of a stuff by captive electromagnetic energy can be expressed in Eq. ( 3 ) as stated in [ 5 ] .
( 3 )
where C is the specific heat of the stuff ( J.kg-1. & A ; deg ; C-1 ) , ? is the denseness of the stuff ( kg.m-3 ) , E is the electric field strength ( V.m-1 ) , f is the frequence ( Hz ) , ? is the dielectric loss factor ( – ) of the stuff, ?t is the clip continuance ( s ) and ?T is the temperature rise in the stuff ( & A ; deg ; C ) .
The ? parametric quantity varies with frequence. For case, ??? of H2O has a extremum in 2.45 GHz frequence. The soaking up frequence of H2O may assist us in warming the H2O in the insects ‘ organic structure but likely all of the other water-composed stuffs nearby may absorb the energy every bit good. A frequence which maximizes the difference between temperature increase in plague and Orchids utilizing the frequence dependent character of ? ( degree Fahrenheit ) is required. With the assistance of Eq. ( 3 ) , the Goal map in Eq. ( 4 ) represents the job which should be maximized.
( 4 )
Using the premise that specific heat of the both stuff are equal, Goal map is reduced to Eq. ( 5 ) .
( 5 )
If we merely presume that electric field is equal in both plague and Orchid parts, the Goal map is reduced to Eq. ( 6 ) .
( 6 )
Therefore, about, it can be stated that we are seeking for a frequence at which the difference between ??? ( degree Fahrenheit ) of the plagues and Orchid is the most possible value. In order to make this, we are traveling to mensurate the effectual permittivity of all Orchid plagues to happen the best frequence in which the difference between ??? of the plague and other stuffs like Orchids is the largest.
There are six challenges that need to be overcome for execution of these thoughts: power, wellness effects, biological effects, monetary value, frequence allotment and design complexness. Power job is solvable if the applied frequence is non higher than GHz. High power beginnings are now common in VHF and UHF frequences and cost is low-cost. Today, electromagnetic moving ridges are known to present for wellness jeopardies and biological defects such as malignant neoplastic disease, but it is reported that take downing the exposure will cut down the jeopardy. Therefore in our method we expose the moving ridges for limited periods which is adequate to increase the temperature of plagues or merchandises. In malice of the wellness and, biological effects of electromagnetic exposure, …… this should be evaluated to guarantee that it does non hold a harmful consequence on the ecosystem.
The job of frequence allotment could be solved for indoor environment every bit good. Taking few frequences to direct in likely VHF and for limited yearss in twelvemonth is non unattainable ; nevertheless we can switch our frequence to ISM sets.
The concluding job is to plan such a program to warm up plagues in different countries. For illustration if we use a individual power beginning, it will be hard to utilize it for terrain uneven train. Therefore for each country, this job should be solved individually and one should plan a suited array of beginnings to cover the country. Additionally the frequence of intervention must be selected in a mode that the soaking up of energy by plague be more than other stuffs.