Pollination of paltas and experience in the NOA
A frequent question between the producers of palta anywhere in the world: Necessary plantar polinizadoras are plants of palta between the plantation of Hass, to assure a high productivity fruits? Answer: according to in what agroclimatic zone is located the plantation. In Argentina measurements were realised on the matter on the interaction of polinizadoras plants of group B put in between a commercial plantation of paltas Hass (group A).
In IV the World-wide Congress of the Avocado in 1999, realised in Michoac¡n, Mexico, there were presentations with respect to this subject. The disertantes, set out the details and results of their investigations, confirming the increase of the final production with the put in plantation of varieties of palta of (group B), within the frame of plantation of Hass plants (group A). In Malaga, Spain, in 2004, during the V World-wide Congress of the Avocado, also expounded itself on these practices, and also in Vi±a del Mar, Chile, during the VI Congreso Mundial of the Palta.
The biologists, disertantes of these investigations, came from California, Israel and Spain, whose zones of culture are semi-desert to desert. Their conclusions, were very effective with respect to the increase of the production by hectare. Immediately, we began to reproduce in our breeding ground, plants of palta of group B. (Zutano, Fort and Collinson B.), recommending to the producers of the Argentine north the use of this practice. But the extrapolation of this technique, in our zone of production, did not give the awaited results.
Differences between trees of palta of the group To and B
Group To, their flowers present their receptive stigma during the morning of the first day, but its just mature pollen to afternoon of the second day.
Group B, its flowers present their receptive stigma to afternoon, and its pollen is mature and pollinates, just to the morning of the next day. The avocado considers a special case called heterodicogamia, in which two different genotypes that they present dicogamia synchronous, have a behavior of reciprocal flowering.
In other words, while the flowers of an individual are in feminine stage, the flowers of the other are in masculine stage, favoring intercrosses it (Alcaraz and Hormasa, 2011). The flowers of palta present dicogamia, that is to say, sequential development of the reproductive functions of the plant. Of Avocado (palta), this dicogamia later consists of two periods of first mature opening, that is to say, the feminine part and of second, the masculine part begins to produce pollen (Alcaraz and Hormasa, 2011). Through the temporary separation of the sexual functions the interweaving is promoted (Richards, 1997), which is excellent, because it exactly indicates adaptations that promote the genic flow between individuals of this species.
Experience in the Argentine Northwest
In year 2002 polinizadoras plants of group B put in between a commercial plantation of paltas Hass (group A), located in the zone of the Gorge of Lules stood, province of Tucuman, in the Argentine northwest. In the spring of year 2005, the Hass trees near the trees pollenizers of group B, they had a significant increase in the amount of dumbfounded fruits. At the home of 2006, the amount of fruits in growth of those trees, was substantially greater than the moved away located plants of Hass more of polinizadoras B.
The experience was giving positive results with respect to the increase of production. At the time of the harvest, in May, the fruits of Hass of the plants near the polinizadoras, were more numerous, but smaller than the most moved away to the trees of group B. That year, was exported to Spain, 1 dollar the kilo palta of first, and to 0.5 dollars palta of the second, smaller one to 200 grams.
The used technique worked so well, that it produced an excess of fruits, but smaller. This situation took place because in this place, and the majority of tropical the tropical zones and sub, they inhabit a great amount of insects pollenizers that, already, of in case, they increase jells. This, added to the action of the polinizadoras plants, gave a detrimental result, in opposition to the awaited one. It had to harvest two small drawers of paltas, and to sell them to the same price that a drawer of paltas with fruits greater to 200 grams.
This negative result taught to us that in Argentine North the technique of pollination attended with paltos of group B is not recommendable, because they exist there, a great amount of insects pollenizers. What gave very good result was the positioning of beehives of bees in the environs of the culture, to obtain an important production.
Reproductive Biology. WideDesktopWallpapers
The vectors that transport pollen are mainly insects, which carry out a key function in the reproduction and increase in the genetic variability of the subtropical avocados, since only through the crossed pollination a considerable amount of fruits (Bergh takes place, 1977; Gustafson and Bergh, 1966; Gazit and Degani, 2002). In the tropical cultures it has been verified that autogamia is sufficient to generate a high productivity of fruits.