Patrícia Milan

Comparative leaf morphology and anatomy of three Asteraceae species

ABSTRACT The objective of this paper was to describe and compare the morphology and anatomy of mature leaves of Mikania glomerata Spreng., Porophyllum ruderale Cass. and Vernonia condensata Baker (Asteraceae) species that have different habits emphasizing their secretory structures. Longitudinal and transversal sections of mature leaf blades of the three species were analyzed at the apex, base, and medium third part of the midvein of the leaf blade and of the margin. M. glomerata had uniseriate glandular trichomes and secretory ducts; P. ruderale had hydathodes and secretory cavities; and V. condensata had idioblasts and uni- and biseriate glandular trichomes. Key words: Mikania glomerata, Porophyllum ruderale, Vernonia condensata, secretory structures, medicinal plants * Author for correspondence INTRODUCTION The Asteraceae family consists of approximately 25000 species (Barroso, 1986) included in over 1100 genera. These species frequently present herbaceous habits, although arboreous and voluble herbaceous habits also occur (Cronquist, 1981). Because of this variety of habits, the family presents various anatomical structures and in some cases ecological specialization may occur (Metcalfe and Chalk, 1950). Secretory structures are of great taxonomical interest and their restricted distribution has an important diagnosis value (Metcalfe and Chalk, 1950; Fahn, 1979). Frequently, in Asteraceae, they occupy distinct positions in different organs of the plant occurring in all, some or in only one organ (Solereder, 1908). Castro et al. (1997) reviewed the types of secretory structures in the leaves of seventy two representatives of the Asteraceae family from the cerrado vegetation in the Reserva Biologica de Mogi Guacu, Sao Paulo, Brazil. When analyzed together these secretory structures presented diagnosis value at genus level. Eight types of leaf secretory structures were mentioned: ducts, cavities, idioblasts, laticifers, hydathodes, extrafloral nectaries, trichomes and glandular appendixes. According to Metcalfe and Chalk (1950), anatomical diversity is commonly observed in the structure of leaves of species belonging to the Asteraceae. Among the features that vary are: (a) stomata distribution on leaf surfaces; (b) guard-cell positioning in relation to ordinary epidermal cells; (c) hypoderm development on the upper side of the leaf surface; (d) mesophyll and fibrovascular system differentiation; and (e) wax secretion on leaf surface (Solereder, 1908). The anatomical features that can be observed in Asteraceae are: (a) presence of various types of glandular or covering trichomes; (b) papillae on

World consumption of fruit juices, nectars, and still drinks

In 2009, the world consumed 117.7 billion gallons of industrialized still drinks. Of the total volume, 77% were consumed in 40 countries, with 23.5 million liters in the juice category, 17 million in the nectar category, 42 million in the category of still drinks, and 35 million in the category of powdered and concentrated juices. In the period from 2003 to 2009, the consumed volume of fruit-based beverages increased by 30.2%. However, since much of this growth came from increased consumption in lower social classes in emerging countries, the increase in the sales volume occurred primarily in the categories of nectars and still drinks, and therefore does not reflect an increased demand for orange juice at 66° Brix, because these are categories of beverages that are diluted in water instead of 100% juice (Graph 37)

Impact of climate change on citrus growing

In recent years, several reputable organizations have warned about the risks of climate change to world agriculture. Things are no different in the citrus sector. Data from the National Institute of Meteorology (Inmet) show that there has been a gradual increase in average temperature in several Brazilian states. The comparison is obvious when comparing the averages between two 30-year periods, i.e. from 1930 to 1960, in relation to the numbers obtained in the measurements from 1960 to 1990. Although the curve has remained the same, one can clearly see that the state of Sao Paulo is warmer. In some regions, such as Limeira and Sao Jose do Rio Preto, the numbers obtained between 1995 and 2009 indicate that the temperature is, on average, about two degrees Celsius higher than the historical average (Figure 6).

Breakdown of the price of orange juice on the retail market

In order to give a breakdown of the costs incurred on orange juice up to the purchase thereof by the end consumer, this topic is dedicated to the breakdown of the price starting with the final sale value as reconstituted juice on the shelves of retailers in Germany, the biggest consumer of Brazilian FCOJ, and ending with the residual value that would cover orange production costs and profit margins of growers and industries in Brazil. Some factors, such as poorly accessible data and differences in legislation, prevented a broader analysis of the European market, which accounted for 71% of Brazilian FCOJ exported in 2009.

Pests and diseases in the Brazil’s citrus belt

This is undoubtedly a major threat to the Brazilian citrus industry. During the last decade, four diseases were responsible for the eradication of 39 million citrus trees in the citrus belt of Sao Paulo and Triangulo Mineiro. As a consequence, the average annual mortality rate, which previously hovered around 4.5% per year, jumped to 7.3 %. Adopting an average yield of two boxes of oranges per tree, it is estimated that citrus canker, CVC, sudden death, and citrus greening accounted for an annual reduction of around 78 million boxes, which - when compared with 317 million boxes harvested in 2009/10 - represents a decrease in harvest of roughly 20% (Table cxm16).

Specialty of the major producing countries

The world’s foremost citrus producers have different destinations for their production, forming a mix between industrial processing (production of juice), domestic consumption of fresh fruit and export of fresh fruit. Brazil, the world’s largest producer of oranges, sends 70% of its production for industrial processing, with Sao Paulo and the Triângulo Mineiro region sending 86% of their production to this market. To get an idea of the importance of the processing industry for these two Brazilian regions, you must realize that, in Brazil, no other fruit is produced for industrial purposes on a level similar to the production of oranges.

The orange flavor in the BRIC group countries plus Mexico

The region formed by the BRIC countries plus Mexico, with 43.4% of the world’s population, consumes 221 thousand tons of FCOJ Equivalent at 66 ° Brix, with 80% in the form of still drinks, 10% in the form of nectar 10% as juice, and a consumption profile per category of beverage typical of countries with lower per capita net income. Between 2003 and 2009, the volume of orange flavored beverages (juice, nectar and still drinks) rose by 50 %, with still drinks rising by 62 %.

Cycle of working capital and available funding sources

The orange juice companies are among those most heavily penalized by the long cycles and slippage between the financing of harvests - due to the disbursement of funds to the suppliers of raw materials - and the receivables from international customers. The need for working capital in the juice industries varies from 9 to 11 months and the larger their stocks between one harvest and the next, the greater their need for working capital.

Phytosanitary barriers and technical requirements

The main destination markets for citrus products, Europe and the United States, are countries with different market legislation. Brazilian exporters are required to comply with a number of demands concerning phytosanitary issues, packaging, consistency in product quality and regularity of delivery.

Price of orange juice: an incredible volatility

The drop in the price for juice coincides with superharvests of oranges in Sao Paulo and/or in Florida. In such a scenario, expectations are for lower-priced oranges and, consequently, lower production costs for the juice. In this way, any news of larger than normal orange harvests leads to a drop in the prices for juice on the New York Stock Exchange and for the European buyers, with direct implications for the price to be paid for oranges by the industry. Inversely, the increases in prices for juice occur at times when the harvests fail, caused by the consequent expectation of increased prices for the oranges and higher production costs for the juice. So, any news regarding a reduction in the orange harvest brings about an increase in juice prices on the New York Stock Exchange, allowing the industry to negotiate new contracts for the sale of juice at higher prices to European importers.