Clean Hop Program Seeks To Beat Disease And Better Bitter Beer


The Clean Hop Program is an ongoing collaboration between researchers at the UW-Madison Department of Plant Pathology, Extension agricultural agents in several counties and farmers interested in getting into the hop business. Clark explained that it has several focuses, including evaluating high-yield and high-quality hop varieties, and assessing which cultivars are well-suited to Wisconsin growing conditions. The goal of the program, now several years along, he noted, is to "develop an economically sustainable system for producing pathogen-free planting stock."

As part of their contribution, UW vegetable pathology scientists researching hops have conducted tissue culture and standard propagation, Clark said, trying to produce disease-free planting material.

Terra Nova Nurseries Announced 25th Anniversary In Plant Breeding

Terra Nova Nurseries, a world leader in plant breeding, today announced the 25th anniversary of its founding. This year marks a quarter century of business since the company’s Ken Brown and Dan Heims formed a professional alliance that would change the face of horticulture.

Along with co-founders Jody Brown and Lynne Bartenstein, they vertically integrated a breeding company and tissue culture facility, combining forces to generate and introduce a stable of more than 1,000 varieties of new perennials and annuals. Many of these new plants have won national and international awards, and ongoing breeding accomplishments have put genera such as heuchera and tiarella on the horticulture map.

Terra Nova Nurseries’ mission during the years has involved best-of-breeding, creative plant introduction marketing, and organizational management practices.

Brown and Heim’s philosophy of hiring phenomenal breeders and talented tissue-culture experts has

Orchids aren’t easy, but that makes them fun

It happened four days before Valentine’s Day, in my grocer’s produce department. A new shipment had just been rolled out from the back room, triggering a full-blown swoon in some of Yakima’s more weather-wearied food shoppers. You’re thinking it was lush strawberries for dipping in chocolate? The first California asparagus? No, it was even more sublime.

Breathtakingly perfect Phalaenopsis orchids had been potted and beribboned for gifting our sweethearts. It’s been a long, long winter, and these pretties had us at “hello.”

The orchid family is so large (25,000 species) that it’s estimated that one in every 15 flowering plants in the world is an orchid. Found in nearly every environment (including above the Arctic Circle), the great majority are tropical. They can be epiphytic, meaning they grow on trees, or lithophytic, growing on rocks. Orchids that grow in soil are called terrestrial, and are usually found in the world’s temperate regions.

Not that long ago, orchids were for the wealthy, or the serious plant connoisseur. They were certainly not something you would grab, along with a bag of potatoes or onions, on a quick trip to the grocery store.

What kept them uncommon is the fact that orchids are notably difficult to propagate from seed. Unlike most seeds, dust-sized orchid seeds lack nutritional storage tissue, which made mass distribution from conventional propagation difficult. These days, new micropropagation techniques, often called tissue culture, and advances in stem cell technology, have made some orchids almost as the ubiquitous as ordinary houseplants, and just as affordable.

Bacterial contaminants of plant tissue culture

Different Methods for Overcoming Integumental Dormancy during in vitro Germination of Red Araza Seeds

Red Araza, or Red Strawberry Guava (Psidium cattleianum Sabine) is a native Brazilian Atlantic Forest species of the Myrtaceae family, whose seeds exhibit integumental dormancy. Due to its importance to different industries worldwide, recent research efforts are seeking to expand this species’ micropropagation processes using in vitro seedling germination, especially since in vitro micropropagation of adult plant material has, so far, been limited. This research effort evaluated different methods of overcoming integumental dormancy during in vitro germination of the Red Araza, so as to allow future micropropagation of the species. The seeds’ emergence and vigor were evaluated based on mechanical and acid scarification, using different substrates and immersions in solutions with different levels of gibberellic acid (GA3), and on the influence of the pre-immersion of seeds in water and sulfuric acid. The mechanical and acid scarification of the seeds, combined or separate, resulted in higher in vitro germination percentages and a higher germination rate index (GRI). Pre-immersion in distilled water (20 hours) also proved to be efficient for the germination of the Red Araza seed, with 76.2% of the seeds germinating and a higher speed of emergence (GRI = 0.18). When compared to a Murashige and Skoog (MS-zero) medium, sowing in a hydrophilic cotton substrate showed greater emergence and vigor, with approximately 70% of the seeds germinating. Treating the seeds by pre-immersing them in GA3 turned out to be unnecessary. The methods used for overcoming integumental dormancy during in vitro germination of Red Araza seeds proved to be efficient, and could be used to develop micropropagation protocols of seminal origin for this species.

Temporary immersion systems in plant micropropagation

Whilst offering several advantages over conventional propagation techniques for cloning of selected plant-ing materials, micropropagation can be an unpredictable and costly production technology. Current techniques require a large number of small containers,semi-solid media and aseptic division of plant tissues by hand. Plant micropropagation involves periodic transfers of plant material to fresh media, after subcultures of 4–6 weeks, due to exhaustion of the nutrients in the medium and also because of continuous tissue growth and proliferation, which is rapidly limited by the size of the culture container (Maene and Debergh,1985). Agar products are not inert and complicate automation. High production costs generally limit the commercial use of micropropagation to products with a very high unit value, such as ornamentals, foliage plants and selected fruit crops (Sluis and Walker,1985; Simonton et al., 1991). Labour generally ac-counts for 40–60% of production costs. Cutting and planting represent the most expensive part of micropropagation (Chu, 1995). Although tissue handling is the major part of the work and the most technical, there is also the cleaning, filling and handling of a large number of containers (Maene and Debergh, 1985).Other major costs result from losses during acclimatization and stem and root hyperhydricity (Reuther,1985). It has been concluded that commercial application of micropropagation for various species wouldonly take place if new technologies were available to automate procedures, and if acclimatization protocols were improved (Kitto, 1997).