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Nectar production, visitors and deposition of pollen in flowers of Cordia nodosa: a species with atypical distyly in the National Forest of Caxiuanã — Melgaço (PA) COELHO CP; RECH, A. R. ; CORREA, F. s. , CARMO, V. S. ; CAVALCANTE, M. c. ; KANASHIRO, M. Resume 1 orlo to view nut*ge Keywords: distyly, Cordia, reciprocal herkogamy Introduction The old family Boraginaceae is presented from small herbs, shrubs, saplings to large trees (Barroso et al. 1991), and differed in four subfamilies that with molecular assessments were raised to the leve’ of families (Gottschling et al. 2001). Among the levated subfamilies we can highlight the Cordiaeceae family, which has about 350 species (Judd et al. 1999) and 65 of them in stigma) and longistylous (low and medium stamens and high stigma ) are called trístilicas (Ganders 1979).

The distylous condition is the most common, occurring in 27 of 28 families of Angiosperms that have heterostyly (Barrett 1992). An interesting feature in distylous populations is the discrete distribution of morphs, due to the genetic control of this trait, but recent studies show that people have a continuous variation in the characteristics distylous, presenting What we call distyly typical, as is the case of polymorphism styles (Richards and Koptur, 1993, Sánchez et al. 2010; Ferrero et al. 2011).

The ratio between the number of individuals with pin and thrum flowers, according to the type of inheritance they show, can also greatly influence the reproductive process of the population_ This ratio is usually (isopletia) (Ganders 1979), but due to an asymmetrical pollen flow, affecting the reproductive success, or causing variations in heterostylous systems, this ratio can be skewed, as is the case of monomorphic populations (Hamilton 1990), or homostylous populations (Coelho & Almeida, 003). ese deviations in the ratio between the morphs are often caused by the presence of self-compatibility in the population (Ganders 1979), and / or a high rate ofvegetative reproduction (Sobrevila et al. 1983).

Several studies highlight the presence of reciprocal herkogamy (HR) as important for the maintenance of distyly because it is responsible for pollen flow between morphs through flower visitors (Heuchera 1979, Barrett 1992, Faivre & McDade 2001), yet Ether authors have questioned the actual efficiency and also its precise manif 10 McDade 2001 yet other authors have questioned the ctual efficiency and also its precise manifestation as a basic requirement to assign a typical distyly to a species (1 992 Dulberger, palller & Thompson 1997).

The absence of typical distyly may result from variation in the supergene, in response to factors related to environmental disturbance (Barrett 1 988, Agren 1 996), geographic isolation or reduction in population size (Jennersten 1988) often the result is the formation ofvariant morphs and / or the situation of total loss of one of the morphs (Ganders 1979, Hamilton 1990, Matsumura & Washitani 2000). These variants can be classified as Homostyly revistylous, Homostyly longistylous, Homostyly intermediate and eventual total loss of one and thrum morphs as monomorphlsm monomorphy (Bawa & Beach 1983, Hamilton 1990).

The monomorphy is the presence of only one floral morph in the population, and this morpho styled ones, but other combinations may exist (Ganders 1979). This fact can be explained by the presence of self-compatibility of the predominant floral morphology, a high clonal growth and / or the possible loss ofthe thrum floral morph (Sobrevila et al. 1983). Based on these variations the study aims to characterize floral Cordia nodosa, highlighting the floral morphology, floral visitors, nectar production and pollen deposition in stigmas, trying thus to evaluate the evidence distyly to a species and efficiency in the success of the species.

Material and Methods The study was conducted at the Ferreira Penna Scientific Station – Forest National Caxiuanã, Melgaço-PA. The area has the ombrophilous forest predominant vegetation – Amazon Rainf Caxiuanã, Melgaço-PA. The area has the ombrophilous forest predominant vegetation – Amazon Rainforest. The studied population of Cordia nodosa is located near the paths urrounding the Ferreira penna Ecological Station We marked 20 individuals of Cordia nodosa using colored ribbons. Flowers were collected for evaluation of floral morphometry, which were measured as shown in Figure 1.

Visitors were observed from direct observations during the morning and evening with notes on the number of visits and behavior during visits, and photographic record, and catches for identification, totaling 30 hours of observation. Notes on time of anthesis and floral characters, such as stigmatic receptivity, pollen release, presence of odor were made through direct observation. Figure 01 – Arrangement of flowers measures obtained in Cordia nodosa in the Ferreira penna Ecological Station – Melgaço, PA. CC- corolla length; AE-height co stigma; EC-length of stigma, anther height AA-, CA- anther length . (Adapted from Consolara, 2008).

For evaluation of nectar flowers were isolated in pre-anthesis, with short pistils and long stamens, where it was made one to five taken throughout the day, thus evaluating the dynamics of nectar production (as shown in the diagram below) and the availabllity of sugar per flower. Glassy microcapillaries IPL were used to emove the nectar and to assess the concentration of hand refractometer. in order to evaluate the efficiency of pollen deposition on pollinators. Statistical analysis was performed using the Systat program . Results and Discussion The floral morphometry showed that the studied population has flowers with about 6. 9 0. 69 mm, with no significant differences between flowers with long stamens and flowers with short pistils. The flowers open between 07:00 and 08:00 h, and remain with the corolla bright until 14:00 h. The stilettos are doubly forked stigmas with 4 terminals, no difference in size between the lowers. The flowers have a variatlon of the distillery, which is characterized by polymorphism style, ie, the flowers have a wide variation in the height of the stigma, but show little variation in the height of the anthers (Figure 02 and Figure 03 A and B).

Thus the reciproca’ herkogamy does not happen, making it dificult to characterize the population as a typical distylous (Sanchez et al. 2008; Sánchez et al. 2010). Figure 02 – Chart showing high values of the height of the anthers and stigmas obtained in flowers of Cordia nodosa in the Ferreira Penna Ecological Station – Melgaço, equires a detailed floral morphometry to identify variations and calculations of herkogamy, and seems to be more common than imagined and may even cause an overestimation of distylous species described (Sanchez, et. al 2010).

When the flowers were evaluated from the ratio between the height of the stigma and anther height is evident the absence of a discrete distribution, showing a continuous distribution and a quantitative trait (Figure 04), this feature is being observed in many species (Sánchez et. al 2008). Figure 04 – Chart showing the ratio of height of the anther and tigma height obtained from flowers of Cordia nodosa in the Ferreira Penna Ecological Station – Melgaço, PA. After 20 hours of focal observations, distributed throughout the day, many visitors were observed on flowers of Cordia nodosa.

The main visitors were bees, followed by butterflies, moths and wasps. Some ants and Hemiptera were observed trying to enter the opening of the corolla, these observations are rare. The bees were responsible for more than 80% of visits (Figure 05), being the most common behavior collecting pollen from the anthers that sit just above the corolla. When the stigmas are ong these visitors touch them during the entire visit, which does not happen when the stigmas are short. The lepidopteran visits were performed less frequently, but with legitimate behavior, introducing the proboscis into the corolla and touching the reproductive organs.

PAGF 10 in the Ferreira Penna Ecological Station – Melgaço, PA. The Plebeia genre was the most important visits in Cordia nodosa. The two species ofthis genus had an eficient behawor in removing pollen trom the anthers touching the stigmas while collecting pollen (Figure 06). In flowers with short stylets it was ot observed the touch of these species on the stigma, thus functioning as pollen robbers. These data reinforce visitors information highlighting key bees as visitors from Cordia species as noted by Machado et al. (2010).

Besides vespids were observed bees, butterflies and as demonstrated by the figure 7 Figure 06 – Species of bee from genus Plebeia registered as the main visitors ofthe flowers of Cordia nodosa in the Ferreira Penna Ecological Station – Melgaço, PA. that the number of flowers sampled was much reduced. [pic] Figure 08 – Dynamic of nectar in flowers with with long pistil nd short pistil in Cordia nodosa flowers in the Ferreira Penna Ecological Station – Melgaço, PA. The pistils collected showed no significant diference regarding the number of pollen grains on the stigma.

This may be an indlcation that even in flowers WIth short stylets, there is a deposition of pollen due the action of floral visitors, thus maintaining a symmetrical flow of pollen. References AGREN J 1996 Population size, pollinator limitation, and seed set in the self-incompatlble herb Lythrum salicaria. Ecology. 77, 1779- 1790. BARRETT S. C. H. 1988. The evolution, maintenance, and loss of self-incompatibility systems. In: Lovett-DoustJ_ (ed. ). Plant Reproductive Ecology: Patterns and Strategies. Oxford University Press, New York, pp. 98—124_ no gênero Palicourea Aubl.

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