Pollination is the single most important aspect for both yield and quality , also in semi - closed greenhouses . rationality enough for Godfrey Dol , specializer in growing in semi - unsympathetic greenhouse , to divvy up selective information about what pollination is , guideline and method .
What is pollination?The constitution of fruit is the product of a plants procreative system . The fruits are a tasty prospect for fauna who spread the cum far and wide . But before the fruit was formed , it was a efflorescence .
The bloom of a tomato plant has both the manly DNA ( anther , which create pollen ) and female DNA ( stigma , which receives the pollen ) of the species . They are separated by a few millimeters only , but without the pollen journey from the anther to the stigma , a tomato plant will not form in good order . Pollination is the story of how pollen travels this brusk distance .
Pollination guidelinesPollination is a mental process that in nature is aid by wind , insects or small brute . It is a natural process and it is therefore no surprisal that there are strong-arm limitations . One of the most distinctly define guideline in the glasshouse diligence is the optimum temperature cooking stove for pollination of tomato plants . At temperature of more than 28 level Celsius , the pollination degrades and above 32 degrees there are serious implications on takings and caliber . agriculturalist want to keep the glasshouse temperature below 28 arcdegree for this ground . It is one of the chief reasons why nursery have wave in cool climates , and why others are built at high altitude . It is also the rationality the semi - unsympathetic glasshouse is embraced in fond climates while in the Netherlands , it suffered a nerveless receipt .
Cool climate and forced cooling allow for the maximal temperature in the glasshouse to be reduced below the danger level for pollenation .
At the lower end of the spectrum , pollination also has a minimum solar day time temperature limit of 16 degree Celsius below which the pollen is not workable .
The second restriction is in humidity . At gloomy humidness , the pollen is too dry and does not flummox to the stigma . At eminent humidity , the pollen sticks to the stamen and does not fall onto the stigma .
In conventional greenhouse , the recommended humidity range is 60 - 75 % . Due to better aura movement , the compass in a semi - closed glasshouse is 70 - 85 % .
distinguish the signsThere are also upper limits for the 24 - 60 minutes temperature , above which pollination is compromised , regardless of low-cal levels . For larger fruiting Lycopersicon esculentum plants such as beefsteak and truss tomatoes on the vine , an medium 24 - 60 minutes temperature of more than 21 degrees Celsius has adverse effect on pollination .
Smaller fruiting tomato plants such as cherry tree and snacking tomato plant hurt pollination problems above 23 degree Celsius .
Individual varieties can have a dissimilar 24 - hour temperature above which the pollination is compromise . When temperature are above these threshold , any means to reduce the day or dark temperature must be used . This include using cooling at nighttime .
One typical physical feature of when the 24 - hour temperature is too high is called stigma exsertion and is shown in build 1 . The stain is sticking out of the prime . This is where the pollen is supposed to be deposited , but because it protrudes the protection that the flower provide , pollination is not possible .
The picture in figure 1 is a tell - tale star sign that the 24 - hour temperature is too high . price can already come about before this symptom is noticed . It should not be confused with daylight temperature higher than 30 degrees . Fig 1 ; The Stigma protruding through the protective flower strobile because of eminent 24 - minute temperature . It is important to point out that exposure to maximal temperatures of more than 30 degrees for a twosome of hours will have negligible effect on pollenation . Nor does one Clarence Day of average 24 - hour temperature of more than 21 degree . However , a full day above 30 degree , or consecutive days with a maximum temperature above 30 degrees Celsius will bear upon pollination .
If the temperature reaches 40 degrees Celsius for one hr there is an immediate effect . For a high-pitched 24 - hour temperature to have effect on pollenation takes at least a one to two workweek . likewise , for pollination to return to normal will take two weeks of cool weather .
Flower temperatureUnderstandably the essence of temperature on pollination is related to flower temperature . The temperatures say above relate to glasshouse breeze temperature , which is what is normally measured . The flower temperature is assumed to be as much as 5 degrees higher than the air temperature . This is strung-out on radiation syndrome . Hence , a high 24 - hr temperature has less effect on pollination when radiation therapy is down , states Godfrey . works that are untested also seem to be able-bodied to withstand higher 24 - hour temperature .
How authoritative is pollinationAll the protection that a glasshouse provides , helps to produce upright quality yield . Without proper pollenation , however , the investment of a glasshouse , heating plant , fertiliser , and labor , is reduced to nothing . ill pollinated fruit have less ejaculate , become gentle , have a shorter shelf life-time , and appear dull .
The glasshouse needs to produce a gamy share of premium fruits to be profitable . Without right pollenation , the per centum of waste material and 2nd - class fruits blend in up , increasing the toll per kilo and the carbon step .
When bumblebees are used properly , the pollination is usually perfect except for when extraneous conditions are utmost , as discussed earlier .
In a few countries , bumblebees are not available and manual pollination must be used . Due to the cost of labor involved in cultivator are tempted to save on pollination cost . It pays to remember the statement above that without proper pollination a Lycopersicon esculentum industrial plant will not raise premium fruit .
Manual pollinationWhen tomato plant are pollinated manually , the best method acting is by using galvanising bees . These are shelling operate vibrators . Staff must hover every flora in the greenhouse three fourth dimension per calendar week . It is tempting to revert to other means of pollination ( tapping crop wires , tap flora with an irrigation hosiery , tapping strings with an irrigation hose , screw the gutter with a reefer or using a blower mount to a streetcar ) , as it is much cheaper .
Under cool , dry condition , this can result in adequate pollination . However , when the weather condition is cloudy or showery , these other methods do not serve .
In Australia , where bumblebee are not allowed , the one-year labour price of pollination with electric bees is as much as 35,000 Euros per hectare per yr . However , mislay one corbel be more than 35,000 Euros . Hence the insisting in providing the plants with the correct pollination method . A fruit that is ill set , can not be turned into a premium fruit .
A better agency to ascertain proper pollenation is to make certain labor is available to pollinate with galvanizing bees on ( cloudy or rainy ) days when pollenation is difficult and cross-pollinate with toll - effective way on good days . This requires a flexible workforce which is not prosperous to achieve .
It also needs to be noted that beefsteak and TOV tomatoes are much more unmanageable to cross-pollinate manually compared to cherry red , cocktail , and snacking tomatoes .
This clause is the first in a serial of three about pollination . Last year Godfrey already started with a series aboutgrowing in a semi - closed in greenhouse . Read here - go’sfor semi - closed glasshouses , cool , the deviation between semi - closed and domiciliation and fan glasshousesandhow to prevent impulse , becoming a harvest to vegetativeandhumidity , for examplein tomato . The last updates in the series were abouta high humidness at nightandCO2 gain and the effect on crop .
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Godfrey DolLinkedIn[email protected]+81 80 700 94 006
