Posts Tagged: Guatemala
IPM information extends to apple and peach growers in Guatemala
As part of the Farmer-to-Farmer Program sponsored by the Partners of the Americas and funded by the United States Agency for International Development (USAID), retired UC IPM entomologist Walter Bentley and Washington State University entomologist Jay Brunner traveled to Guatemala in April to help growers improve the peach and apple industry. Their primary goal was to identify pest problems and possible solutions to help peach and apple growers improve fruit production, taking into account the region's unique climate.
“The most important issues were horticultural,” said Bentley. “The region's biggest need is for a horticulturist or plant pathologist.”
Some of the peach varieties require 300 to 500 chilling hours.
“Peach trees at elevations of 7,500 to 9,000 feet above sea level bloom for 2 months whereas bloom in California lasts just 10 days," he said. "You would get situations where the top half of the tree was in bloom while the bottom half was already producing fruit.”
This creates an environment favoring disease development and causing further problems for growers if the disease was severe enough to warrant a pesticide treatment. If a tree was partially in bloom while simultaneously producing fruit, it would have to be hand-sprayed multiple times so that the portion of the tree that warranted treatment was sprayed.
Although most of the important issues that Bentley and Brunner found were horticultural or disease-related, there were some insect problems. Many growers had stink bugs and other plant bugs attacking their trees. Spider mites and predatory mites were also observed. Growers sprayed pyrethroids after bloom to help prevent plant bug damage. However, applying pyrethroids reduced predatory mites, leading to an outbreak of spider mites.
After spending seven days touring four to six farms per day and looking at various practices, Bentley and Brunner spent the next week leading workshops for farmers and discussing integrated pest management (IPM) approaches to managing problems. Using the UC IPM website, specifically the Pest Management Guidelines for apples and peaches, Bentley and Brunner were able to teach sampling methods, stress the importance of correct pest identification, and encourage growers to spray with the least toxic and disruptive products. Bentley and Brunner were surprised by the large variety of pesticides available to growers, but were encouraged that farmers were willing to spray only when necessary while being open to other methods of control.
Bentley and Brunner were impressed by the staff that took them around to each farm and by the growers who were receptive to new ways of managing pest problems. The farmers were very appreciative of the advice they received and were very generous. “Everywhere you went people wanted to share what they had,” said Bentley. “They are amazing people.”
Humbled by the experience, Bentley reflected, “I'm glad I went. I've been given a lot in my life and wanted to give back a little.”
Avocado Botanical Races
Department of Botany and Plant Sciences, University of California Riverside.
Evidence of avocado selection by human hand as far back as 8,000 BC is preserved in archaeological sites in Puebla State, Mexico. At the time of European contact, written records indicate that there already existed three distinct types of avocado, each from a separate geographic center of origin. Today, we refer to them as botanical races, and they represent the “primeval soup” that gave rise to modern avocado cultivars. Here is what we know about the three botanical races of avocado, respectively called (1) the West Indian (formerly known also as the South American), (2) the Guatemalan, and (3) the Mexican (also known as the “criollo”): Each exhibits a characteristic suite of traits that includes differences in leaf chemistry (a distinctive anise scent is found only in Mexican race avocados), peel texture and color, fruit oil content, and sources of tolerance (diseases and salinity). The races were domesticated in separate geographic regions, the “West Indian” race in lowland coastal Mesoamerica (possibly Yucatán), the Guatemalan race in upland Guatemala, and the Mexican race in highland Mexico. The Guatemalan and Mexican races remained fairly local, so their names reflect their respective centers of domestication, but the “West Indian” race seems to have been spread far and wide by indigenous cultures in Meso- and South America and was, incorrectly, named for a much later destination. The explorations of the 15th and 16th centuries kicked off the worldwide distribution of (mostly West Indian race) avocados, reaching Spain in the early 17th century, Jamaica in the mid-17th century, and Indonesia by the mid-18th century. It wasn't until the mid- to late 19th century that the three races of avocado found their way to the United States, primarily Florida and California, where they underwent many rounds of selection and hybridization. ‘Hass', the cornerstone of the California avocado industry, was patented in 1935 but its ancestry is unknown. It is considered to be a Mexican x Guatemalan hybrid because its leaves lack the anise scent and its fruits combine the thick, rough skin of the Guatemalan race but the high oil content of the Mexican race.
avocado vars