2015 News You Can Use


Tomato Leaf Spotting Diseases Identified in the NMSU Plant Diagnostic Clinic

Image of Phoma rot on tomato
Figure 2. Phoma rot on tomato (Photo: N. Goldberg, NMSU-PDC)
Image of early blight on tomato
Figure 1. Early blight on tomato (Photo: J. French, NMSU-PDC)

Tomato leaf spotting diseases Identified in the NMSU - Plant Diagnostic Clinic- Two different fungi which cause leaf spots on tomatoes have recently been identified in the NMSU Plant Diagnostic Clinic: early blight, caused by Alternaria solani, and Phoma rot, caused by Phoma destructiva. These two leaf pathogens occur under similar environmental conditions and produce similar symptoms on plants. Test, don't guess! These diseases look similar to each other, and in fact, look similar in appearance to other tomato diseases. As such, a laboratory test is recommended to properly identify the causal agent. Samples can be submitted to the NMSU - Plant Diagnostic Clinic through the NM County Extension Offices.

Early blight begins as small, brownish black spots (Fig. 1). The tissue around the spot may turn yellow and when spots are abundant on the leaf, the whole leaf may turn yellow. Spots rapidly increase in size. As they enlarge, concentric rings may become visible in the dark brown tissue. As the disease advances, leaves may become blighted and necrotic and the plant may drop leaves prematurely. Phoma rot begins as irregularly shaped, sunken lesions develop on both the upper and lower leaf surfaces (Fig.2). As the lesions expand, they become 'zonate' (an appearance of concentric rings). The tissue around the lesions may become yellow or necrotic. Over time, lesions may grow together resulting in leaf blight and premature defoliation. Pycnidia (black fruiting bodies) embedded in the diseased tissue distinguishes Phoma rot from early blight. Check out this Pathology Factsheet for more information on and photos of these two diseases. Contact: Natalie Goldberg or Jason French


NMSU Plant Diagnostic Clinic Launches New Features

Image of NMSU Plant Diagnostic Clinic Facebook page
NMSU Plant Diagnostic Network Facebook page (photo: NMSU-PDC)

NMSU Plant Diagnostic Clinic Launches New Features - Spring has arrived, plants are growing, and pests are lurking. Never fear, if problems should arise, the New Mexico State University Plant Diagnostic Clinic is here to help. As the new growing season gets underway, we'd like to remind you of the resources of the Plant Clinic. It is a full service, fully integrated, plant diagnostic lab which will process samples for plant diseases and disorder, plant and weed identification and arthropod identification. Submitters are encouraged to utilize the clinic's online submission system, NMSU DDDI. The NMSU's Distance Diagnostics System PowerPoint presentation provides instructions on how to use the system. Earlier this year, the NMSU Plant Diagnostic Clinic received a Gap Audit from the National Plant Diagnostic Network's Star-D Lab Accreditation Program, an important first step toward National accreditation. The audit findings were very favorable and we anticipate full accreditation within a year. When accredited, the NMSU Plant Diagnostic Clinic will be among the first labs accredited nationwide. The Plant Diagnostic Clinic strives to provide rapid and accurate plant diagnostic services. To ensure that our services are meeting the needs of our clientele, we have developed a customer feedback survey, which can be found at the bottom of your diagnostic report. We hope that you will take just a minute of your time to let us know how we're doing. We are also pleased to announce that the NMSU Plant Diagnostic Clinic now has a Facebook page - please Like us on Facebook! Contact: Jason French or Natalie Goldberg

Alfalfa Losses High Due to Alfalfa Weevils

Image of an adult alfalfa weevil
Adult alfalfa weevil (Photo: Patricia Monk, NMSU)

Alfalfa losses High Due to Alfalfa Weevil - This has been the heaviest weevil years in many years throughout New Mexico. As usual, losses are lightest in the Mesilla Valley which has high levels of biological control. Heaviest losses seem to be in the middle Rio Grande area which also is typical but losses are much higher than normal. Biological control in New Mexico ranges from very low to quite effective. At the Agricultural Science Center in Artesia 85% of weevils were parasitized in mid-April but some nearby fields were damaged suggesting lower levels of control. Most of New Mexico has one parasitoid, Bathyplectes spp. which is often not numerous enough to control alfalfa weevil before the first cutting. In the Mesilla Valley we have two species of parasitoids. Bathyplectes spp and Oomyzus incertus and generally higher levels of control. Nationwide growers have found that two parasitoids are needed for very effective control. Efforts are underway to establish Oomyzus incertus in additional areas of New Mexico. Effective management strategies and more photos can be found in the NMSU Extension Publication Guide A-338: Alfalfa Weevil Control Options in NM. In addition to those insecticides listed in the publication, Steward is recommended by many consultants. It has quick knock down, a short cutting restriction and is softer on beneficials than the other insecticide options. In using this product technical representatives recommend Steward 6 oz / A plus Silken 4 oz / A using at least 5 gallons per acre. If there are adults you can add 11.1 oz / A of Lorsban but if there was a concern about beneficials consider just using the Steward. If a second treatment is necessary you can go back 7-10 days later with 5.1 oz of Steward and 4 oz of Silken. Contact: Jane Pierce


Turfgrass Experts Teach Kids About the Water Needs of Artificial Turf

Image of Specialist's teaching kids about water conservation
Elena Sevostianova and Bernd Leinauer teach kids about the water needs of artificial turf at the Water Festival (courtesy photo).

Turfgrass Experts Teach Kids About the Water Needs of Artificial Turf - On Thursday, April 16 the City of Las Cruces organized a Water Festival at Young Park to inform and educate third and fourth graders about energy, water, and water conservation. There were about 25 different booths set up at which the school children learned about water issues in the desert. From 9:00 am to 1:30 pm third and fourth graders walked from station to station and listened to and participated in 10 to 15 minute long presentations and activities. Elena Sevostianova and Bernd Leinauer from the Extension Plant Sciences Department set up rug-sized patches of artificial turf and natural grass at their station and presented real world information on the heat build-up and heat dissipation from artificial turf. The kids first stepped bare feet on the artificial turf and then on natural grass to feel the difference. Afterwards they used an infrared thermometer and measured the temperature on both surfaces. The temperature on the artificial grass was from 20 to 40 degrees higher and reached a maximum of 109 degrees just around noon. The natural grass patch reached a maximum of 80 degrees. When asked how to cool artificial turf most of the kids answered that it needed to be watered. After the artificial grass was irrigated from a watering can kids measured surface temperature again and it recorded the same level as the natural grass. When water requirements were compared for a hot summer day, we determined that the artificial grass needed 10 to 15% more water to stay cool. Both teachers and kids commented that our station was informative and it was interesting to learn that artificial grass needs to be watered in order to make it a safe playing surface. Contact: Bernd Leinauer


Turfgrass Specialist Teaches Water Conservation & Turfgrass Maintenance at Asian Golf Show in China

Image of Dr. Leinauer with Chinese Students
Dr. Bernd Leinauer with students from Shanghai Jiao Tong University (courtesy photo).

Turfgrass Specialist Teaches Chinese Students About Water Conservation and Turfgrass Maintenance at Asian Golf Show in China - In early March, Bernd Leinauer, New Mexico State University professor extension turfgrass specialist, traveled to Beijing and Xiamen, China, to speak at the Asian Golf Show on water conservation and teach students about golf course maintenance. The Golf Course Superintendents Association of America, the Reed Guanghe Exhibitions and the Golf Institute at the Shanghai Jiao Tong University invited him to give a series of lectures. "Our research program in the turfgrass water conservation program has been recognized nationally and internationally by both scientists and practitioners as one of the leading programs in the world," Leinauer said. "The Chinese government will begin regulating water use on golf courses on July 1, 2015, and the organizers of the show wanted to use the opportunity to present different perspectives on reducing irrigation water use on golf courses." Leinauer and Clint Waltz from the University of Georgia were selected by the GCSAA to speak about irrigation water conservation and water management. Both scientists have presented regularly at the national Golf Industry Show organized by the GCSAA and are recognized as experts in the field. After the presentation at the Golf Show, Leinauer traveled to Xiamen, a city in southern China, where he met with students from the Shanghai Jiao Tong University at a newly constructed golf resort. He lectured on various golf course maintenance practices, such as mowing, fertilization, as well as irrigation for golf green construction and water conservation. "It took a lot of time and effort to prepare for the trip because all teaching material had to be submitted well ahead of time to be translated into Chinese. It was interesting for me because I had to lecture with all my slides in Chinese," Leinauer said. "I was really honored to be invited. It was a great experience for me. Everybody was very friendly and hospitable." He added there is a possibility for collaboration in the future to help China with their water issues. It shows that "the work we do is relevant not only to New Mexico and the U.S., but also applies to other countries," he said. Contact: Bernd Leinauer

New Sorghum Aphid Pest Likely in New Mexico This Year

Image of a map showing the locations of sugarcane aphid
Figure 2. Map showing the distribution of sugarcane aphid
Image of a sugarcare aphid
Figure 1. Sugarcane aphid (Photo: Entomology and Plant Pathology Department, Oklahoma State University)
Image of a greenbug aphid
Figure 4. Greenbug aphid (Photo: Entomology and Plant Pathology Department, Oklahoma State University)
Image of yellow sugarcane aphid
Figure 3. Yellow sugarcane aphid (Photo: Entomology and Plant Pathology Department, Oklahoma State University)

New Sorghum Aphid Pest Likely in New Mexico This Year - Sorghum growers need to be aware of the possibility of finding sugarcane aphid (Fig. 1) in New Mexico. Sugarcane aphid is a new aphid pest of sorghum. This aphid either expanded its diet from eating sugarcane to sorghum or came in as a new biotype. Over the last year the sugarcane aphid moved from south Texas to the Panhandle. Last fall it was collected northwest of Lubbock, near Plainview, and near Amarillo Texas. It was also collected in Oldam County, Texas, west of Amarillo on the border of New Mexico (see distribution map - Fig. 2). It might be in New Mexico now but NMSU entomologists did not find any in surveys last fall. Growers, consultants and county agents are urged to be aware of the possibility of sugarcane aphid and to notify NMSU entomologists as soon as anyone spots the aphid. Unfortunately we cannot apply for a section 18 for the most effective insecticide, Transform, until we find sugarcane aphid in New Mexico. Sugarcane aphid looks similar to some other sorghum aphids, particularly yellow sugarcane aphid (Fig. 3) and greenbug (Fig. 4). However, it is easy to distinguish the three species. Unlike sugarcane aphid, yellow sugarcane aphid has numerous hairs on its back, and the greenbug has a green stripe down its back. Populations of sugarcane aphid can be enormous. They reproduce rapidly within four days of birth. Growers can see losses of 25-50 percent. Some fields have been so bad that growers have abandoned them. One of the biggest problems is when the aphids' sticky secretions, honeydew, clog harvesting equipment. Significant losses can occur when insecticides are not applied until populations have exploded, which can happen very quickly. For this reason scouting twice a week is recommended once aphids are found. Beneficial insects often help control insect pests in New Mexico, but growers cannot expect beneficials to keep up with this rapidly reproducing pest. Dry desert conditions also help control many insect pests in New Mexico so there may be some control from desiccation in grain sorghum. However, in forage sorghum the canopy is so dense that we will likely not see any control from desiccation. Fortunately, if an effective insecticide is applied at the recommended economic threshold of 50-125 aphids per leaf, growers can generally see good control with just one application. Contact: Jane Pierce


NMSU Plant Clinic Hosts NPDN STAR-D Auditor Training

Image of participants in the training
Participants in the NPDN STAR-D auditor training held in Las Cruces, NM in February 2015 (Photo credit: Jenna Gilbert, NMSU)

NMSU Plant Diagnostic Clinic Hosts NPDN STAR-D Auditor Training - The NMSU Plant Diagnostic Laboratory, housed in the Extension Plant Sciences Department, hosted a National Plant Diagnostic Network (NPDN) STAR-D (System for True, Accurate and Reliable Diagnostics) Auditor Training the week of February 23rd. The NPDN is a collective effort among Land Grant Universities, federal agencies, and state departments of agriculture, whose mission is to enhance agricultural security through the protection of plant health and productivity. The STAR-D program was designed to create and maintain a diagnostic laboratory accreditation process that enables the laboratories to follow similar requirements and standards striving to meet consistency, accuracy and timeliness of testing, documenting and reporting plant pests. The participants included the audit trainers (three NPDN STAR-D trainers and a professional International Standards Organization 17025 trainer) and ten auditor trainees from around the United States. The training consisted of three days of intensive classes and exercises for the trainees and a gap audit of the NMSU-Plant Diagnostic Laboratory. The gap audit serves as a preliminary review of the laboratory's quality management system which includes assessment of the facilities, equipment, personnel and procedures; and is the first step toward STAR-D accreditation. Contact: Natalie Goldberg or Jason French