Central Ferry Research Articles

Spectral indices for characterizing lentil accessions in the dryland of Pacific Northwest

Lentil is a cool season legume crop suffering terminal stress in different parts of the world, especially in North America, Australia, Southwest Asia and North Africa. Drought stress, which is often linked with high temperatures, is very damaging to grain legumes in practically all agricultural environments. In this experiment, 49 accessions were sown with a check variety in an augmented design in Whitlow farm 2015, central ferry farm 2016 and Spillman farm 2016, Washington state university. The three different locations were in the dryland of southeastern Washington. The collected 49 accessions were screened, where 32 accession were taken from the United States Department of Agriculture's single plant-derived core collection and 16 from lentil reference population of ICARDA and one check variety was Avondale. Secondary traits such as green Normalized difference vegetation index (GNDVI), red Normalized difference vegetation index (RNDVI), photochemical reflectance index (PRI), red Normalized difference vegetation index (RNDVI), water band index (WBI), and normalized water index (NWI) were collected using a multi spectral reflectance device and agronomic metrics such as days to flowering (DF), biomass yield per plant (BYP) and seed yield per plant (SYP) data were also collected as well. Multi trait genotype ideotype distance (MGIDI) addresses the restrictions of AMMI and GGE analysis by using BLUP and ideotype distance, which can properly select genotypes considering higher yields as well as consider other desirable parameters GNDVI, RNDVI, PRI, WBI, NWI. The accessions Avondale, PI 368647, ILL7090, PI33690, PI 5187, ILL 86, ILL595, PI 533690, PI 518734, ILL 1649, ILL 4781 were selected as the ten best genotypes and Avondale, ILL7090, PI533690 were less affected by G x E interaction and selected for further evaluation based on AMMI, GGE and MGIDI index.

Genetic Dissection of Heat Stress Tolerance in Faba Bean (Vicia faba L.) Using GWAS.

Heat waves are expected to become more frequent and intense, which will impact faba bean cultivation globally. Conventional breeding methods are effective but take considerable time to achieve breeding goals, and, therefore, the identification of molecular markers associated with key genes controlling heat tolerance can facilitate and accelerate efficient variety development. We phenotyped 134 accessions in six open field experiments during summer seasons at Terbol, Lebanon, at Hudeiba, Sudan, and at Central Ferry, WA, USA from 2015 to 2018. These accessions were genotyped using genotyping by sequencing (GBS), and 10,794 high quality single nucleotide polymorphisms (SNPs) were discovered. These accessions were clustered in one diverse large group, although several discrete groups may exist surrounding it. Fifteen lines belonging to different botanical groups were identified as tolerant to heat. SNPs associated with heat tolerance using single-trait (ST) and multi-trait (MT) genome-wide association studies (GWASs) showed 9 and 11 significant associations, respectively. Through the annotation of the discovered significant SNPs, we found that SNPs from transcription factor helix–loop–helix bHLH143-like S-adenosylmethionine carrier, putative pentatricopeptide repeat-containing protein At5g08310, protein NLP8-like, and photosystem II reaction center PSB28 proteins are associated with heat tolerance.

Genecology of Thurber’s Needlegrass (Achnatherum thurberianum [Piper] Barkworth) in the Western United States

Thurber’s needlegrass (Achnatherum thurberianum [Piper] Barkworth) is a key restoration species in the Great Basin and surrounding areas, yet comprehensive studies of how climate relates to genetic variation and seed zones for restoration projects are lacking. Potentially adaptive phenotypic traits of 66 diverse populations of Thurber’s needlegrass were measured in common gardens at Central Ferry, Washington and Reno, Nevada in 2012 and 2013. Extensive genetic variation was observed among phenology, morphology, and production traits (P < 0.01), and canonical correlation was used to relate traits to source climate variables. Only with the first two canonical variates were F values significant (P < 0.05), explaining 42% and 18% of the variation, respectively. For variates 1 and 2, strong canonical correlations of 0.97 and 0.94 linked genetic variation with source climates, providing evidence for climate-driven evolution. Pearson linear correlations indicated that populations from warmer, drier locations generally had earlier blooming and longer awns than those from cooler, wetter locations. Plants from warmer, drier locations also had higher survival at Central Ferry and higher leaf length to width (narrower leaves) at Reno in 2012. Regression of the canonical variates 1 and 2 for traits with source climate variables produced very strong models, explaining 94% and 87% of the variation in plant traits. These models were used to map 12 seed zones encompassing 465 079 km2 in the Great Basin and surrounding areas with six seed zones representing 90% of the mapped area. We recommend using these seed zones to guide restoration of Thurber’s needlegrass.

Adaptation of Autumn‐Sown Faba Bean Germplasm to Southeastern Washington

Information regarding the suitability of autumn‐sown faba bean (Vicia faba L.) in southeastern Washington is lacking. Therefore, a variety trial testing the effects of two sowing dates was conducted for two seasons (2011–2012 and 2012–2013) at three locations: Central Ferry Research Farm (CF), Pomeroy, WA; Spillman Agronomy Farm (SF), Pullman, WA; Whitlow Farm (WF), Pullman, WA, with 20 northern European breeding lines, or cultivars, and U.S. Department of Agriculture‐Agricultural Research Service National Plant Germplasm System (USDA‐ARS NPGS) sourced germplasm accessions with predetermined winter‐hardiness. Winter‐hardiness and yield varied depending on location, timing of sowing, and genotype effects. Survival was greatest at CF where the extreme low air temperature was –6°C, yet multiple entries tolerated an extreme low of –14°C in Pullman. In both years, the second sowing at the CF location improved survival, whereas the first sowing was only beneficial at the Pullman locations when seedlings were established before the first hard frost. Providing a longer establishment and cold acclimation period was expected to optimize hardiness and yield potential. However, achieving two to three nodes before the first hard frost was difficult at dryland managed SF and WF locations where soil moisture was limiting. Across entries and site‐years, the mean survival was 65% with a yield of 2800 kg ha−1. To realize the potential of autumn‐sown faba bean in southeastern Washington, genotypes with earlier maturity than the northern European materials tested herein will be needed.

Registration of Four Winter-Hardy Faba Bean Germplasm Lines for Use in Winter Pulse and Cover Crop Development

Faba bean (Vicia faba L.) is a versatile crop grown for food, feed, vegetable, or cover crop purposes in many countries. In response to the growing demand for winter annual legumes for cover crop development in the United States, we developed four winter-hardy faba bean germplasm lines, WH-1 (Reg. No. GP-3, PI 674326), WH-2 (Reg. No. GP-4, PI 674327), WH-3 (Reg. No. GP-5, PI 674328), and WH-4 (Reg. No. GP-6, PI 674329) at the USDA-ARS, Western Regional Plant Introduction Station, Pullman, WA, after six consecutive seasons of overwintering selection at three farms in two locations; Pullman and Central Ferry, WA. These four accessions were identified after the initial screening of 175 accessions from the USDA faba bean germplasm during the 2008–2009 and 2009–2010 winter seasons. In the following years, these populations were compared with several winter-type cultivars and breeding lines from Europe. During the final testing season, in 2013–2014, selected and original accessions were compared. The average increase in percentage survival was 84% across the four accessions. Furthermore, the winter hardiness of the selected accessions was comparable to European materials. These four lines are potential reservoirs of useful diversity accessible for the development of a winter annual legume cover crop in the U.S. Pacific Northwest and other regions up to USDA plant hardiness zone 6b.

Agronomic Performance of Spring‐Sown Faba Bean in Southeastern Washington

Faba bean (Vicia faba L.) is the world's fourth most important cool‐season pulse crop. Currently commercial faba bean cultivars are unavailable in the United States specifically selected for grain production; therefore, a spring‐sown variety trial with 11 populations was conducted for two seasons at two contrasting locations in southeastern Washington. Early seeding was expected to achieve optimal grain yield. In 2012, the warmer Central Ferry, WA, location was sown a month earlier than at Pullman, WA (April vs. May), resulting in earlier flowering, higher grain yield, and an earlier maturity across populations. A drier March–April in 2013 allowed similar sowing dates across locations, synchronizing phenological development and improving grain yields at Pullman. However, at Central Ferry, yield was reduced due to high temperatures (&gt;35°C) and subsequent flower and pod shedding. The National Plant Germplasm System (NPGS) accession W6 12023 and the Extra Precoce Violetto × Hiverna/2 F3:5 breeding population were the highest yielding populations and earliest to flower and mature in 2012 and 2013, respectively. Across 4 site‐years, W6 12023 proved to have superior general adaptability with a high mean plant yield (22.6 g plant−1). Yield data compared favorably to other spring sown pulses currently grown in the region; therefore, a multi‐environment trial with early maturing spring‐type cultivars is warranted.

Comparative Growth and Development of Hexaploid and Tetraploid Reed Canarygrass

ABSTRACTReed canarygrass (Phalaris arundinacea L.) is a globally distributed forage grass potentially useful as a biofuel. It occurs at more northern latitudes as a tetraploid but also as a less‐studied hexaploid (revised to Phalaris caesia Nees) at equatorial to mid‐latitudes in Europe and Africa. In this study, growth and development of ploidy types were compared on six hexaploid and four tetraploid accessions at Pullman (PU) (cooler, wetter), and at Central Ferry (CF) (warmer, dryer), WA, locations. Six phenological, seven morphological, and seven production traits were measured in 2010 and 201l. Plant survival was near 100% for both ploidy types at both locations despite temperatures as low as −24°C. There were frequent interactions with year and location but hexaploid reproductive development averaged 5–8 d later than tetraploids. Ploidy groups had equal production at CF in 2010, averaging 513 g per plant, and at PU in 2011, averaging 1151 g per plant. But in 2010 at PU, tetraploids produced more than twice the dry wt. of hexaploids, and in 2011 at CF hexaploids produced 39% more than tetraploids (P &lt;0.01). Using all traits and accessions, principal components 1 and 2, explaining 67% of the variation, strongly distinguished ploidy groups at PU both years, but CF groups in 2010 were somewhat more diffuse. Although high production for both ploidy groups occurred at PU in 2011, the higher production of hexaploids at CF in 2011 suggested a potential for expanded use in warmer, dryer climates.

Genetic Variation of Wheat streak mosaic virus in the United States Pacific Northwest

Wheat streak mosaic virus (WSMV), the cause of wheat streak mosaic, is a widespread and damaging pathogen of wheat. WSMV is not a chronic problem of annual wheat in the United States Pacific Northwest but could negatively affect the establishment of perennial wheat, which is being developed as an alternative to annual wheat to prevent soil erosion. Fifty local isolates of WSMV were collected from 2008 to 2010 near Lewiston, ID, Pullman, WA, and the United States Department of Agriculture Central Ferry Research Station, near Pomeroy, WA to determine the amount of genetic variation present in the region. The coat protein gene from each isolate was sequenced and the data subjected to four different methods of phylogenetic analyses. Two well-supported clades of WSMV were identified. Isolates in clade I share sequence similarity with isolates from Central Europe; this is the first report of isolates from Central Europe being reported in the United States. Isolates in clade II are similar to isolates originating from Australia, Argentina, and the American Pacific Northwest. Nine isolates showed evidence of recombination and the same two well-supported clades were observed when recombinant isolates were omitted from the analysis. More polymorphic sites, parsimony informative sites, and increased diversity were observed in clade II than clade I, suggesting more recent establishment of the virus in the latter. The observed diversity within both clades could make breeding for durable disease resistance in perennial wheat difficult if there is a differential response of WSMV resistance genes to isolates from different clades.

Yield and Yield Components of Winter‐Type Safflower

ABSTRACTSafflower (Carthamus tinctorius L.) is a minor yet widely grown oil seed crop adapted to semiarid regions. The development of winter adapted safflower, permitting fall planting, could substantially increase seed production. Our objective was to compare seed production of winter‐type and spring‐type safflower under fall and spring planting regimes. From 2006 to 2009 four winter‐type safflower germplasms and two spring cultivars were compared at Central Ferry, WA, Pullman, WA, and Pendleton, OR, in seven year–location combinations. For all years and locations the minimum average winter temperatures in December and January were always below freezing, with annual extremes ranging from ‐11 to ‐26°C. Extensive winter mortality of fall‐planted, spring‐type cultivars generally resulted in little or no seed production. For each year, seed production of fall‐planted, winter‐type germplasm was always higher than when spring planted (P &lt; 0.05), averaging 310 g m‐2 or 66% more. That advantage was also observed at all locations within years except Pullman and Pendleton in 2009. Anthesis of fall‐planted germplasm averaged 16 d earlier than when spring planted. Increased production of fall‐planted winter‐type germplasm was most closely associated with increased seeds per square meter resulting from more capitula per square meter or seeds per capitulum. The results showed that fall‐planted winter‐type safflower has the potential to substantially increase seed production compared to spring types.

Safflower Winter Survival and Selection Response Relates to Fall Growth Morphology and Acclimation Capacity

Fall‐planted safflower (Carthamus tinctorius L.) offers potentially higher yield than spring‐sown types. Yet winter survival in relation to fall growth and physiological aspects of acclimation has not been determined. Our objectives were (i) to determine the relationship between fall growth and winter survival in safflower, (ii) to assess if selection improved winter survival, and (iii) to determine if water relations and membrane leakage distinguished safflower varying in winter survival. Fall growth, leaf water relations, and leaf membrane leakage were measured in fall 2004 and 2005 at Pullman and Central Ferry, WA, and winter survival was determined. Average minimum winter temperatures were 1.0°C at Central Ferry and −3.9°C at Pullman, with extremes of −7.2°C at Central Ferry and −19.5°C at Pullman. For the 21 accessions evaluated, low fall plant habit was required for survival, but survival also varied substantially among low‐habit types. Two cycles of recurrent mass selection on five low‐habit types improved winter survival from 21 to 59% at Central Ferry and from 8 to 18% at Pullman. The highest survival was for BJ‐27 after two selection cycles, averaging 90% at Central Ferry and 38% at Pullman. Accession BJ‐27 maintained higher leaf pressure potential during fall acclimation in 2004–2005 and in 2005–2006 had higher pressure potential and membrane stability on the 8 January sampling than less‐hardy types. The results show that both low habit and physiological acclimation capacity are needed for high winter survival in safflower.

Registration of WSRC01, WSRC02, and WSRC03 Winter‐Hardy Safflower Germplasm

Winter‐hardy safflower (Carthamus tinctorius L.) germplasm lines WSRC01 (Reg. No. GP‐38, PI 651878) WSRC02 (Reg. No. GP‐39, PI 651879), and WSRC03 (Reg. No. GP‐40, PI 651880) were developed at the USDA–ARS, Western Regional Plant Introduction Station, Pullman, WA. All three lines were developed from germplasm originating in China and derived from two cycles of recurrent mass selection. Plants of each original accession were fall planted at Pullman (elevation 786 m), and seed of surviving plants was bulked for each cycle. In tests at Pullman and Central Ferry (elevation 206 m), WA, selection increased winter survival an average of 4.1% for WSRC01, 25.3% for WSRC02, and 94.5% for WSRC03, with the increase significant for WSRC02 and WSRC03 (P &lt; 0.05). Average winter survival for WSRC01 was 88%, for WSRC02 84%, and for WSRC03 78%. Survival for spring‐type cultivars was zero in all tests. This is the first release of winter‐hardy safflower and is expected to be useful in breeding improved winter safflower with potential adaptation to areas of the western United States and the southern Great Plains, in addition to international regions such as the Mediterranean basin and southwest Asia.

Autumn growth and its relationship to winter survival in diverse safflower germplasm

The relationship between several autumn growth traits and winter survival was determinedin 11 diverse safflower (Carthamus tinctorius L.) accessions grown at Central Ferry and Pullman, WA, USA. The safflower was sown in September 2002 and 2003 and plant population counts were taken 6-8 wk after emergence, and after the last frost in the spring to calculate winter survival. Growth factors including plant habit and height were also measured in the autumn. The Pullman plots in 2003–2004 were lost during an usually cold and windy November, but otherwise survival ranged from 90% for BJ-27, an introduction from China, to zero for the cultivar Saffire. Winter survival was negatively correlated with more upright plant habit (r = -041**, n = 97) and plant height (r = -0.29**, n = 97). However, some accessions with low plant habit (prostrate growth) and low height values had relatively poor survival. The results show that BJ-27 has sufficient winter survival to achieve over-winter safflower production for many areas. Autumn plant habit and height can predict the potential for winter survival, but physiological factors related to cold acclimation appeared to determine if that potential is realized. Key words: Carthamus tinctorius, safflower, winter hardiness, cold tolerance

Bee Associates of Flowering Astragalus and Onobrychis Genebank Accessions at a Snake River Site in Eastern Washington

A 3 yr survey of the bee associates of flowering accessions of Astragalus and Onobrychis species was conducted in open-pollinated field nurseries at Central Ferry, Washington to gain insight into the potential for bee-mediated inter-accession out-crossing in these nurseries. Such nurseries are used by genebank managers at the USDA-ARS Western Regional Plant Introduction Station (WRPIS), Pullman, Washington, to multiply seed of accessions low in viability and/or supply. Fifty-two species of bees (Hymenoptera) in the Andrenidae (4 species), Apidae (18), Colletidae (1), Halictidae (5), and Megachilidae (24) were recorded. Species-rich genera were Bombus (8 species) and Osmia (16). One undescribed species of Osmia was collected. The bee fauna was more diverse on Astragalus (45 bee species) compared to Onobrychis (29 species). Among the 24 Astragalus and 13 Onobrychis species censused, bee diversity was highest on A. bungeanus Boiss. (24 bee species), A. chaborasicus Boiss. & Hausskn. (24 species), A. miser var. serotinus (A. Gray ex J.G. Cooper) Barney (14 species), A. cicer L. (13 species), A. schistosus Boiss. & Hohen. (12 species), A. onobrychis L. (11 species), A. podolobus Boiss. & Hohen. (11 species), and Onobrychis viciifolia Scop. (10 species). The presence of a rich bee fauna in WRPIS nurseries at Central Ferry, including documented pollinators of the allogamous species A. cicer and O. viciifolia, could complicate efforts to prevent hybridization and maintain genetic integrity of genebank accessions of allogamous plant species. Our results support a 1993 decision by WRPIS curators to discontinue the practice of clustering accessions of single species of Astragalus and Onobrychis in open-pollinated nurseries to regenerate seed.

Wild Allium spp. as Natural Hosts of Iris yellow spot virus.

The incidence of Iris yellow spot virus (IYSV) of genus Tospovirus, family Bunyaviridae in a commercial onion crop was first confirmed in Washington state during 2003 (1). First found in Adams County, IYSV has rapidly spread to all onion-producing counties in the state, affecting seed and bulb crops. The USDA-ARS Western Regional Plant Introduction Station (WRPIS) collects, maintains, and distributes various Allium (garlic and onion) accessions. As part of the regeneration process, accessions are grown under field conditions at the WRPIS farms in two locations: Pullman and Central Ferry, WA. Symptoms indicative of viral infection, now known to be caused by IYSV, first appeared in field-grown accessions in 1999. In June 2005, leaf and scape tissues were collected from WRPIS accessions of wild onions (Allium pskemense, A. vavilovii, and A. altaicum) in Central Ferry that had symptoms indicative of IYSV infection (2). IYSV infection was confirmed using enzyme-linked immunosorbent assay with a commercially available kit (Agdia Inc., Elkhart, IN). Virus infection was further verified using reverse transcription-polymerase chain reaction (RT-PCR) with primers derived from the small (S) RNA of IYSV. The primers flanked the IYSV N gene (5'-TAA AAC AAA CAT TCA AAC AA-3' and 5'-CTC TTA AAC ACA TTT AAC AAG CAC-3'). RT-PCR gave a PCR product of expected size (≈1.2 kb). The DNA amplicon was cloned and sequenced. Nucleotide sequence comparisons with known IYSV N gene sequences showed 95 to 98% sequence identity. The prevalence of the vector, onion thrips (Thrips tabaci), combined with the widespread incidence of IYSV in seed and bulb production areas of the state may have resulted in natural infection of wild relatives of cultivated onion. The potential role of wild Allium spp. in IYSV epidemiology remains to be determined. Information on the extent of IYSV infection of onion germplasm would be useful in identifying potential sources of host plant resistance to IYSV.

SEED TREATMENT INSECT CONTROL IN SPRING WHEAT, 2004

An experiment consisting of a RCB of 6 seed treatments (4 replicates) was seeded using a small plot drill on 7 Apr (60 lb acre) at the USDA-ARS Western Regional Plant Materials Introduction Center at Central Ferry, WA. Seeding was into failed winter wheat which had been seeded on sweet corn ground to encourage wireworm presence. The crop emerged on 12 Apr. Wireworm damage was evaluated by mean plant stand counts per 18 inches of row at 10 DAPE. Mean grain heads per plant were counted prior to harvest as a measure of plant vigor. Differences in plant stand varied between treatments with the two rates of Poncho and Gaucho 480 0.32 fl/oz cwt being significantly higher than the other treatments and UTC. Heads per plant were significantly higher for the two rates of Poncho compared to the other treatments and the UTC. Since RWA appeared after plant stand and head counts were established, differences in plant stand are attributed to wireworm attack on the seedling plants. RWA appeared at just prior to anthesis, and at 48 DAPE counts of mean percent RWA infested tillers were made. Yield data in bu per acre were collected by small plot combine 22 Jul. All 5 seed treatments provided better control of RWA compared to the UTC. PonchoTM 600 provided slightly better yields compared to the 0.32 fl oz/cwt Gaucho 480 treatment. These 3 treatments were better than the other treatments, and the UTC.

REDUCTION OF BARLEY YELLOW DWARF VIRUS VECTORED BY APHIDS IN WINTER WHEAT, 1998

REDUCTION OF BARLEY YELLOW DWARF VIRUS VECTORED BY APHIDS IN WINTER WHEAT, 1998: Plots were seeded by large plot drill on 23 Sep, 1997 in a RCBD with four replicates per treatment at the USDA-ARS Western Regional Plant Materials Introduction Center at Central Ferry, WA. Replicates were 45 x 350 ft. Gaucho 480 was applied at 3 rates as a seed treatment insecticide at 1.0, 1.5, and 2.0 oz product cwt. An untreated check was established at seeding. Counts of BCOA were made on day of emergence (0-DAE), 7-DAE, 15-DAE, 22DAE, and 30-DAE. BCOA is a principal vector of barley yellow dwarf virus (BYDV) in fall seeded cereals. The trial was rated for BYDV at 100-DAE in Jan of 1998, using a scale of 0 to 6, where 6 = 100% of plants expressing symptoms of BYDV. Yield data were collected at harvest in Jul.

Controll Of Insect Pests on Spring Canola, 1997

Abstract Plots were established in a RCBD 4 replicates of 6 X 20 ft. at the USDA-ARS Western Regional Plant Materials Introduction Center at Central Ferry, WA. Treatments were made at full bloom with a CO2-powered backpack sprayer at 20 gpa at 20 psi on 24 Jun, 1997 except for 4 rates of Gaucho 75 ST applied as seed treatments at planting on 28 May. All sprayed insecticides were buffered to pH 5.0. Treatments were evaluated for pre-treatment count 46 DAE, 2 DAT (48 DAE) and 10 DAT (56 DAE) by counting the number of CA colonies per m2 (6.6 linear ft of row) with mean number of CA per colony. Counts of CSPW exit holes per 100 pods per replicate were made at harvest, and yield data was collected

Imidacloprid (GAUCHO 480) as an Aphicide in Winter Wheat, 1997

Abstract Plots were seeded by large plot drill on 10 Oct 1996, in a RCBD with 5 replicates per treatment at the USDA-ARS Western Regional Plant Materials Introduction Center at Central Ferry, WA. Gaucho 480 was applied at 2 rates as a seed treatment insecticide at 0.5 and 1.0 oz (AI)/cwt. Lorsban 4 E SG was applied topically by sprayer at 26 d after emergence (DAE) on 7 Nov due to weather conditions prior to that date. An untreated check was established at planting.

Early-Season Flea Beetle Control on Spring Canola, 1997

Abstract Plots were seeded 19 May at the USDA-ARS Western Regional Plant Materials Introduction Center at Central Ferry, WA, at a rate of 6 lb/acre in rows 7 inches apart. Plots were 6 X 20 ft. replicated 4 times in a RCBD, situated next to a crested wheat grass field. Treatments of CR-10 at 2.5 lb product/acre were applied as granules with the seed, and 4 rates of Gaucho 75 ST were applied as seed treatments at planting. Four other treatments were made at the appearance of FB 3 d after emergence (DAE) with a CO2-powered backpack sprayer at 20 gpa at 20 psi. A mean of 20 FB per 6.6 ft of row was present at the time of treatment. The plants were in the early cotyledon stage of growth. FB damage was rated on a scale of 0 to 6, with 0 = no damage, and 6 = total destruction of apical meristem at the pre-treatment count, 7-DAT, 12-DAT, 15-DAT, and 20-DAT.

Late-Season Flea Beetle Control on Spring Canola, 1997

Abstract Plots were seeded 28 May at a rate of 6 lb/acre in rows 7 inches apart at the USDA-ARS Western Regional Plant Materials Introduction Center at Central Ferry, WA. Plots were 6 X 20 ft. replicated 4 times in a RCBD, situated next to a crested wheat grass field. Treatments of CR-10 at 2.5 lb product/acre were applied as granules with the seed, and 4 rates of Gaucho 75 ST were applied as seed treatments at planting. Four other treatments were made at the appearance of flea beetles 2 d after emergence (DAE) with a COz_ powered backpack sprayer at 20 gpa at 20 psi. An untreated check was established. A mean of 80 FB per 6.6 ft of row were present at the time of treat-ment. The plants were in the early-cotyledon stage of growth. FB damage was rated on a scale of 0 to 6, with 0 = damage, and 6 = total destruction of apical meristem at the pre-treatment count, 2-DAT, 5-DAT, 9-DAT, and 15-DAT.