Major row crops, such as corn, soybeans and cotton, are genetically engineered to tolerate pests, such as weeds and insects. These crops are able to tolerate herbicides but will kill weeds and/or are able to kill insects upon feeding on crop parts. Undoubtedly, these modern technologies are essential to keep up with the increasing demand for food and fiber; however, the safety of GE foods to human health, the environment and socio-economic implications are vital for their long-term adoption.
A consumer is often bombarded with mixed messages regarding the safety of GE foods. Claims and viewpoints related to the positive and negative effects vary widely. The National Academy of Sciences appointed a committee to perform a rigorous and scientific review of available information to address food safety, along with its environmental and socio-economic aspects. Their findings were released during the summer of 2016 in a 584-page report.
The plum curculio, Conotrachelus nenuphar (Herbst), is an important early-season pest of tree fruits. They can cause considerable damage to apple, pear, apricot, peach, plum, nectarine, cherry and other fruits.
Plum curculio adults are a type of weevil (or snout beetle), approximately 6 mm (¼ inch) in length with a mottled combination of brown, black and gray colors over the body. They have four small humps on their wing covers (elytra) and a characteristic curved snout (Figure 2).
There has been exponential increases in the number of weeds resistant to various herbicides commonly used to manage them, especially in field crops in the last 25 years. To better understand herbicide resistance and to minimize its development, we should examine the processes that govern it. Herbicides may classified into various families or groups based on the growth process affected by the herbicide, referred to as mode of action. Slight differences in the genetic makeup of a very small fraction of the population of a particular weed species, referred to as a biotype, may allow them to tolerate a particular herbicide group. So, when herbicides belonging to the same group are used in a given area over lengthy periods, populations of such weeds build up through selection pressure. The particular species is then referred to as an herbicide-resistant weed. The primary cause of herbicide resistance is the repeated use of the same herbicide, or herbicides, with the same mode of action.
The life cycle of the weeds play an important role in the development of resistance. Annual weeds with shorter life cycles develop resistance faster. Perennial weeds take longer time to develop resistance. More and more instances of weed biotypes are reported as evolving resistance to glyphosate. Common weeds, such as horseweed (Figure 5) or marestail ( Conyza canadensis ), waterhemp ( Amaranthus rudis ), palmer amaranth ( Amaranthus palmeri ), common ragweed ( Ambrosia artemisiifolia ), giant ragweed ( Ambrosia trifida ) and johnsongrass ( Sorghum halepense ), have been reported as resistant to glyphosate in the United States.
The best thing to do at this point is to clean up. Grassy areas would greatly benefit from vigorous raking that would stimulate and invigorate grass growth. Spreading some fertilizer will account for early luscious grass growth. The other focus of our attention should be on ornamentals, which may require some pruning.
There are several reasons for pruning. Nicely trimmed shrubs and trees not only look better, but they are healthier too. Start by removing all dead, diseased and damaged shoots and limbs. Next, remove all the limbs that are crossing and rubbing, serving as a source of injury that will result in increased disease and insect injury potential.
In order to improve the vigor on your hydrangea, remove some of the oldest shoots. The best blooms tend to be on the younger two- to five-year-old shoots. The shoot-removing cuts should be made at the soil line.
Historically found in the Great Plains or prairies of the mid-western United States, the eastern coyote (Canis latrans) is becoming more and more common across West Virginia. Over the past 100 years, the coyote has expanded its range across the United States and most of North America.
Records for the coyote in the mid-Atlantic states date back only 50 years, with the first record of a coyote in West Virginia appearing in the 1970s. This remarkably rapid expansion has been due in part to the near extinction of larger predators, such as the mountain lion and timber wolf, and also to the population growth of white-tailed deer. Humans have also aided in the coyotes’ expansion by moving and releasing coyotes for sport hunting. Coyotes are very adaptable in what they eat and where they live; therefore, they have been able to easily expand into forested, agricultural, suburban and urban environments.
Late blight resistant West Virginia ’63 tomato is a favorite to organic and small growers in West Virginia. However, its susceptibility to Septoria leaf spot caused by the fungal pathogen Septoria lycopersici concerns growers.
Cornell University released a F₁ hybrid, Iron Lady, with resistance to Septoria leaf spot and late blight resistance partly obtained from the WV ’63. We crossed the WV ’63 with the Iron Lady and selected field-grown plants resistant to Septoria leaf spot. We tested for this tolerance by inoculating six-week old, nutrient-stressed plants in the greenhouse. The WV ’63 plants were killed; whereas, the hybrid selections survived.
You have heard the old adage that “an ounce of prevention is worth a pound of cure” and in high tunnel production that is sound advice. Pest management inside a high tunnel is particularly difficult, because there are few chemicals registered for use on crops grown in them. Also, the structure is vented to the outside, which allows the possible influx of pests on a regularly basis.
Weeds are a constant problem inside and outside of growing structures. Weeds compete with your crop for light, nutrients and water. They also increase the possibilities of insect and disease problems by harboring these pests in or around your tunnel. Finally, they can reduce air circulation within structures when they are vented.