NAPOLEÃO ESBERARD DE MACÊDO’s scientific contributions

The present paper had the objetive to imprive the knowledge for ecofisiological studies. With herbaceus cotton (Gossypium hirsutum L. r. latifolium Hutch.) taken into consideration a non destructive method to estimate the area and volume of the fruits that also had chlorophyll and take part actively is the photosyntesis as a modification in the method of Hozumi et al. (1955) to growth analysis. Through linear measures of the length and width of the fruit and using the general equation of the ellipse and of the revolution ellipsoid, it is possible to estimate the aiel and volume of the fruit accurately, and through periodic measures, the absolute and relative rate of growth, the measures of height and caulinar diameter of the plants and volume of the plants in time intervals (for example 15 days) during the plants life.

Herbaceous cotton plant samples (Gossypium hirsutum L. race latifolium Hutch.), from Embrapa Cotton cultivar BRS Sucupira, from several farms of the Barreiras county, in the harvest time 2001/2002, showing rottenness were analyzed by Embrapa Cotton. It was verified that the rottenness was caused by several environmental factors: long period drought, that raised quikly the senectitude of plants, followed by intense rain and cloudy days, and also the presence of insects, as the soybean thumbtack (Nezara viridula) and the corn cartridge caterpillar (Spodoptera fungiperda) that damage the fruit, and open the way to bacteria and fungus. The occurrence of the "false-fruit" is probably of genetic nature, induced by environmental pressure (long period drought followed by a lot of rain and nutritional unbalance, specially the boron). The mentioned cultivar itself has mocó cotton genes, a natural trihybrid (G. hirsutum, G. mustelinum and G. barbadense), increasing the occurrence of abnormalities when compared with genotypes of one species only. Probably, it is a case of non-complete fertilization, controlled by a Se gene (G. barbadense) that induces the formation of twin embryos. Cytogenetic studies are necessary to check this hypothesis.