alogamia entre dos variedades de frijol común en Fraijanes y Alajuela, localidades del Valle Central de Costa Rica. La parcela experimental consistió en tres. compatible clones CCN51, and the self-incompatible clones TSH clones, were made studies of . autogamia facultativa (39,,9); alogamia facultativa. Rosilda Mara MussuryI* and Wedson Desidério FernandesII para realização de alogamia, como por exemplo pólen abundante, néctar e odor. de vigor inferior, quando comparadas aos testes de autogamia, polinização natural e cruzada.
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Studies of the floral biology and aautogamia system of Brassica napus L. Studies of the floral biology of canola were accomplished with the objective of enlarging the system and reproductive strategies knowledge of its CTC-4 cultivar in Dourados, Centerwest, Brazil. Brassica napus is self pollinated, presenting however, many resources for the allogamy accomplishment, e.
The smaller anther were responsible for the production of fruit with smaller and less growth seeds, when compared to the autogamy, autopollination and cross pollination tests. Brassica napusCanola, floral biology. Among the plants with an economical importance, it is the family of the cruciferae, including about kind and more than 4.
Canola Brassica napus L. In spite of these favorable characteristics for crop periods, few researches have been developed in Mato Grosso do Sul, although this species represents a great alternative for the State. A study developed by Williamsconfirmed that colza flowers produced nectar and pollen in abundance and they were extremely attractive to the bees. Although Williamsobserved in a colza plantation, that the bees collected pollen and nectar, and that the pollen concentrations transported by the wind were larger in the hot, dry and sunny days than in cold, humid and cloudy days.
Williamschecked that wind, transporting considerable amounts of pollen in the field, promoted the autopollination and the crossed pollination of the flowers, still influencing in the fruit yield with longer beans, which contended more seeds and a larger weight. Eisikowtichshowed that the wind can help the auto-pollination. With the objective of understanding the mechanism of canola reproduction, in order to obtain subsidies for its handling and appliance, its floral biology and reproductive system were studied.
Inthe studies of floral biology were accomplished in the period from July to October in stonemasons measuring 1. Seeds of Brassica napus were used cultivar CTC-4sowed with spacing of 20 cm among the arrays and with 12 plants for linear meter.
To observe the morphology of the flower and the sequence of events that precede the anthesis, 20 floral buttons were used in different development stages. The following characteristics were observed: The anthers were observed under magnifying glass to verify the dehiscence type and the beginning of this process was correlated with the stage of the floral development. With the purpose of detecting the essence presence, thirty flowers were placed tightly in closed recipients for a period of 60 minutes and then opened and smelled, according to the technique suggested by Almeida and Dafni For the verification of lipid substances in the exina of the pollen grains and the presence of starch, the reagent Sudan III and Lugol were used, respectively Johansen, The activity of the nectaries was evaluated every two hours, and the schedule of larger nectar production was evaluated through the observation of the polinators occurrence.
To study the reproductive system, autogamy, xenogamy, crossed pollination, smaller anthers and natural pollination tests were performed. For each test, the following characters were appraised: The autogamy was evaluated through the sacking of 20 inflorescences and of 20 individualized floral buttons of 0.
The inflorescences and the buttons were sacked 24 h before the floral anthesis, with thin fabric sacks, endowed with breathing pores and observed daily until the obtaining of fruit that were measured in length.
The xenogamy tests were totally accomplished in 25 buttons emasculated before the dehiscence of the anthers. Both the buttons were artificially pollinated, as those from where the pollen was removed, they were protected with thin fabric sacks in order to avoid the contamination with pollen of other flowers.
POLINIZACIÓN Y DISPERSIÓN by on Prezi
Immediately after the anthesis, the flowers were pollinated. The pollen was taken from the stigma by means of a dissection needle previously sterilized. Soon after, the flower was sacked again and observed until the formation of fruit. U crossed pollination was evaluated in 20 floral buttons, emasculated before the dehiscence of the anthers. With the aid of a dissection needle, the pollen transfer was accomplished among the flowers which were sacked, and then observed daily until the obtaining of the fruit.
For this test, 30 floral buttons were marked with colored ribbon to verify the mean number of fruit produced under natural autlgamia. To observe the alogamiw of the pollen grains of the smaller anthers, the larger anthers of 20 floral buttons were removed with 0. Soon after, the pollen of the smaller anthers was taken on the stigma of the same buttons. The development of the fruit was daily accompanied. All the fruits obtained through each test had their fruits measured in length and their seeds were counted and separated.
The mean weight autogamja the seeds was obtained accurately through the evaluation of five lots of ten seeds in analytic scale of 0. The seed germination test was accomplished with five repetitions of ten seeds, except for autogamy where three repetitions were accomplished. The seeds were placed in gerbox boxes, with double layers of filter paper.
After seven days, the boxes were placed in a germinator and maintained during a period of five days, the number of normal plant seeds was computed at the end. The plant seeds were measured in total length from hypocotyl to radiclewhich obtained the alogwmia average of 10 plants three repetitions for each test.
To study the reproductive system, six treatments, [ autogamy test, crossed pollination, xenogamy, natural pollination and smaller anthers]. The flowers of B. The anthers present auogamia dehiscence. The ovary is a superior type, with parietal placentation, gamocarpelar and bicarpelar.
There are nectaries located in the center of the flower, two between the ovary and the short stamens and two between the long stamens autgoamia the petals Fig 1.
The test of the exsudation from the nectaries indicated the carbohydrates presence in the nectar, reducing sugar and fructose. In field collections, during the period of 9: In this period, larger yield was obtained. The floral buttons with 0.
The alogania placed on the stigma in the buttons with 0. In buttons with 0. The matured nectaries secreted nectar, beginning the first phase of the floral opening pre-anthesis.
When the flower became 1. This fact was confirmed through the sacking of the floral button and posterior transformation in fruit.
The smaller anthers didn’t reach the stigma in this phase.
The pollen alogaamia down the stigma with high concentration of starch, which represented a primary source of energy for the polinators. The intra-floral nectaries produced nectar in great amount during the whole pre-anthesis phase. In this phase, it was observed that Trigona sp. It held on the corolla with the aid of the legs and it began the cutting of the walls, using the jaws.
This cutting was made in the place of nectar elimination and it enlarged progressively, resulting approximately zlogamia an circular opening, with a variable size. In agreement with the size of the hole, Trigona sp. In the second phase, the flower reached the mean size with 1.
AUTOGAMIA – Definition and synonyms of autogamia in the Portuguese dictionary
The bees reach easily the intra-floral nectaries, atogamia needing, however, to move away the floral pieces that were open. When the insects visited the flowers in search of nectar, the pollen grains were stuck to their bodies, mainly in the ventral part and they were taken to the stigma of other flowers.
In pre-anthesis, the buttons marked to evaluate the ragged time for the flower to reach the anthesis, it was observed that this was completed in about 20h, being the available rewards to the polinator for a mean period of 48h.
In reason of the asynchronism and intermittence during the opening of their flowers, the slogamia activity during one day, stays intense, promoting a constant flow of reward to the insects visitors. Probably, the scent developed an important role when provoking instinctive reactions, especially in insects.
The authors affirmed that the great amount of chemical energy spent in the production of the scent was evidenced by the disappearance of starch during the odoriferous phase of the anthesis. Similar results were observed during the anthesis phase when there was a decrease of the starch in flowers above 1. There were larger amounts of starch in buttons below 1.
Chrysomelidaeand Trigona sp. Apidaethat tear the floral button in search of food. In the third post-anthesis phase, the secretion of the nectaries was quite reduced, and the anthers, petals and sepals wither dropping soon after, with the remaining of the stigma that accompanies the fruit until the next ripening.
Meaning of “autogamia” in the Portuguese dictionary
Table 1 indicates the values obtained for the analysis of the characters in each test. It was observed that B. According to Alberts et al. In agreement with Williams and Eisikowtichthe flowers of B. In the present work, the smaller anthers of cultivar CTC-4 presented viable pollen.
However, in the pre-anthesis and anthesis stages, these anthers didn’t reach the stigma, and did not participate in autpgamia noticeable form of the fertilization process. The same ones produced small fruits, with smaller number of seeds, and the plant seeds presented a reduced growth, although no significant differences in relation to the other tests was observed Table 1.
In xenogamy tests and crossed pollination, it was observed that the size and the number of seeds were inferior in relation to the autogamy test and natural pollination. This happened probably, due to the manipulation accomplished in the floral button and in the stigma, during the emasculation and the pollen deposit.
However, the seeds presented larger mean weight and also presented the plant seeds height, for the tests of crossed pollination and xenogamy. This demonstrated that the reproductive strategies used by the species in study were important in the genetic increment of the species, favoring the occurrence of more adaptive characteristics. In agreement with Dan et al. This is one of the requirements for the increment of the vegetable production, with the advantage of they present better condition to complete the biological cycle in adverse conditions.
In the present work, it was observed that in artificial conditions xenogamy test, crossed pollination and smaller anthersthe size and the number of seeds were smaller Table 1. However, there is a possibility that in natural conditions, the alogamy happens with a larger frequency, due to mainly the high populational density of the polinators associated h the reproductive strategies of the plant.
These differences are added in order to aurogamia the development of important autogzmia characteristics for the species, as size of the fruit, number of seeds, and others. Independent to the reproductive system used by B. This was also observed by Almeida and Vidal et al. Possibly, the competition for photo-assimilation is the main reason for the general position of fruits in the sub terminal area of the inflorescence, due to insufficient translocation of food for the terminal area of the inflorescence, alogxmia the miscarrying of a great number of floral buttons and flowers.
Although pollen autoamia is apogamia autogamia test and inter-plant presence of polinator insects and pollen grains stuck to its bodythe same ones don’t participate in a definitive way in the fertilization process, once autogamix pollen autogaima by the larger anthers is enough for the fertilization of the ovules.
Through the accomplished studies, it was observed that, although neither the fruits obtained by the crossed pollination have been larger, nor presented larger number of seeds, the presence of the polinator was important to obtain fruits with seeds weighting larger. That indicates that autogamiq is a larger aloagmia of nutritional reserve in the seed, favoring the germination and the development of the plant seeds.
A detailed knowledge of biological aspects, as the floral biology and the reproductive system of Canola, are very important for a safe introduction of this species in Mato Grosso do Sul, as well as for the development of techniques adapted for the handling of this species. Tese Mestrado Rio de Janeiro.