Bean Height Research Articles

Influence of Irrigation Levels and Mulching Types on Growth and Yield of Bean in Drought Prone Area of Bugesera, Eastern Rwanda

Purpose: Water saving practices are crucial for crop production in drought prone areas. This study was conducted in Bugesera District, in the Eastern Province of Rwanda. The objective was to determine the effect of irrigation levels and mulching types on growth and yields of beans. 
 Methodology: A split plot experiment consisting of three irrigation levels as main plots and three mulching types (no mulch, grass mulch and plastic mulch) as subplots, in a Randomized Complete Block Design (RCBD), with three replications was conducted. Climbing bean, Mac 44 variety, was planted at 50 cm × 20 cm spacing. Different levels of irrigation and mulching were applied from 3 weeks after crop emergence. Irrigation water was applied using a manual watering can.
 Findings: Bean height and grain yield varied significantly due to the combined effects of irrigation × mulching. Highest value of plant height, 100 grain weight and yield value were obtained under the combination of 50% irrigation level with grass mulch. Compared to the control, yield improvement of 83%, 100 grains weight improvement of 39% and plant height increase of 20 % were observed under I1M1. Significant and positive correlations were observed between yield, plant height and yield parameters. The observed interdependence of yield parameters is illustrated by the positive and significant correlation between these parameters. Combining irrigation and mulching would improve climbing production while saving irrigation water up to 50%.
 Recommendation: Both plastic and grass mulch gave similar results, however grass mulch is recommended for climbing bean production in the study area due to its additional advantages over the plastic mulch. 

Tolerance of azuki bean to herbicides applied preplant for weed control in a strip‐tillage cropping system

AbstractFive field experiments were conducted at Huron Research Station near Exeter, Ontario, Canada, during 2018 to 2020 to assess the tolerance of strip‐till‐grown azuki bean to various preplant (PP) herbicides. The herbicides selected have activity on glyphosate‐resistant (GR) Canada fleabane, an emerging weed biotype in strip‐till azuki bean production. Saflufenacil, metribuzin, 2,4‐D ester, saflufenacil + metribuzin, saflufenacil + 2,4‐D ester, metribuzin + 2,4‐D ester, and saflufenacil + metribuzin + 2,4‐D ester, applied PP 1 week before seeding, at the proposed label rate (1X) and twice that rate (2X) caused as much as 6%, 5%, 6%, 7%, 8%, 10%, and 13% visible azuki bean injury. The herbicide‐induced azuki bean injury was transient and had no effect on plant density, aboveground dry biomass, height, maturity, and yield except for the dry biomass which was reduced by 28% with metribuzin + 2,4‐D ester and 36% with saflufenacil + metribuzin + 2,4‐D ester at the 2X rate and azuki bean height which was reduced 9% at the 2X rate with saflufenacil + metribuzin + 2,4‐D ester. Based on these results, saflufenacil, metribuzin, 2,4‐D ester, saflufenacil + metribuzin, saflufenacil + 2,4‐D ester, and metribuzin + 2,4‐D ester applied PP have potential for GR Canada fleabane control in strip‐till azuki beans. However, there is not enough crop safety for using a three‐way tankmix of saflufenacil + metribuzin + 2,4‐D ester, applied PP, in azuki bean production.

INNOVATIVE BIOLOGICAL PRODUCTS IN ORGANIC BEAN GROWING TECHNOLOGY

The application of microbiological products in agriculture is becoming more and more relevant nowadays in order to reduce the use of chemical products. These products have the potential to protect plants from diseases, pests, increase yields and improve quality and are friendly to the environment. The aim of the study was to evaluate the effect of the innovative biological product Sporeplus on bean growth and productivity, to evaluate the impact of the product on the prevalence of diseases. The study was carried out at Vytautas Magnus University Botanical Garden. Beans of 'Tiffany' and 'Bobas' varieties were studied by applying the microbiological product as a seed treatment and spraying the plants during vegetation with a product suspension. The highest average bean height was defined in both 'Bobas' (significantly) and 'Tiffany' (insignificantly) varieties sites, where bioproduct Sporeplus was applied for both seed treatment and for later plant spraying during vegetation. Significantly the highest average seed weight per plant was determined in beans of the 'Tiffany' variety, where the seed was treated by bioproduct and also the plants were sprayed with the microbiological product Sporeplus during the vegetation period as well. The average seed weight per plant of the 'Bobas' variety was also the highest (insignificantly) where both the seed and later the plants were treated with the microbiological product Sporeplus. The prevalence of bean rust (Uromyces fabae) was not significantly affected by the application of the microbiological product Sporeplus.

Tolerance of Four Market Classes of Dry Beans to Tribenuron and Carfentrazone Applied Preplant

Limited information is available on the sensitivity of dry beans to tribenuron and carfentrazone applied preplant (PP). Four field trials were conducted at Exeter and Ridgetown, ON, Canada in 2019 and 2020 to determine the tolerance of azuki, kidney, small red and white beans to glyphosate (1800 g·ae·ha-1) + tribenuron (15 g·ai·ha-1), glyphosate (1800 g·ae·ha-1) + carfentrazone (35 g·ai·ha-1) and glyphosate (1800 g·ae·ha-1) + tribenuron (15 g·ai·ha-1) + carfentrazone (35 g·ai·ha-1) applied PP 1 - 2 days prior to seeding dry beans. Glyphosate + tribenuron, glyphosate + carfentrazone, and glyphosate + tribenuron + carfentrazone, applied PP, caused 5%, 5% and 9% bean injury at 1 WAE; 7%, 6% and 10% bean injury at 2 WAE and 6%, 5% and 8% bean injury at 4 WAE, respectively. At 8 WAE, there was 0, 1% and 4% injury in azuki bean; 1%, 2% and 2% injury in kidney bean; 3%, 2% and 3% injury in small red bean; and 6%, 3% and 2% injury in white bean with glyphosate + tribenuron, glyphosate + carfentrazone, and glyphosate + tribenuron + carfentrazone applied PP, respectively. The injury was significantly greater with glyphosate + tribenuron in small red and white beans compared to the azuki and kidney beans. There was no difference between injury levels among market classes of dry been with glyphosate + carfentrazone or glyphosate + tribenuron + carfentrazone applied PP. There was no effect of glyphosate + tribenuron, glyphosate + carfentrazone and glyphosate + tribenuron + carfentrazone on dry bean plant stand, maturity and seed yield. However, dry bean biomass was reduced as much as 15% with glyphosate + tribenuron and 13% with glyphosate + tribenuron + carfentrazone compared to the untreated control. Dry bean height was reduced 4% with glyphosate + tribenuron + carfentrazone but was not affected with other treatments. Based on these results, there is potential for using glyphosate plus tribenuron or carfentrazone for preplant weed management in dry bean production.

ВПЛИВ ПОЗАКОРЕНЕВОГО ПІДЖИВЛЕННЯ ПЛАНТАФОЛОМ НА ДЕЯКІ ФІЗІОЛОГІЧНІ ПОКАЗНИКИ І ПРОДУКТИВНІСТЬ СОЇ КУЛЬТУРНОЇ (GLYCINE MAX MOENCH.)

The efficiency of influence of Plantafol (10.54.10) foliage application on soybeans in soil and climatic conditions of the Ternopil region was investigated. It was found that Plantafol increased the green weight of top and plant density, the total mass of grain per plant, its significance and therefore increased the grain crop by 4.9 c/ha.The crop growth was due to the formation of 15.0% higher biomass green weight of top with higher plant stand by 8% and the increase of seed productivity mainly by increasing of the total weight of seeds in plants by 10.2% and its significance by 7.9 % in comparison with the control. By the influence of Plantafol, there was an increase of the height of beans fastening by 6.4%, as well as a tendency to increase the number of beans by 5.7% and the number of seeds per plant by 2.1%.The chlorophyll fluorescence induction technique was used to isolate a group of fluorescence parameters of chlorophyll a, in particular φNPQ, φNO, which can determinate variations in the productivity of the variety, as they are sensitive to the foliage application.There wasn’t found the direct influence of the mineral fertilizer on the quantum yield of photochemistry PS II (ФPSII). At the same time, the abundance of chlorophyll (SPAD) increased.It is assumed that the decrease of the ECSt level, observed under the conditions of Plantafol foliage application of plants, led to the decrease of NPQt and φNPQ levels in soybean.In the absence of significant difference in the rate of linear electron flux in the experimental and control groups, Plantafol decreases the NPQt level and causes the increase of the total number of active RC FS I.The obtained data proved the significance and the perspective of foliage application using as of complex mineral fertilizers during soybean cultivation that increases its productivity in local soil and climatic conditions.The Plantafol reduces the negative effect of some nutritional elements in soil and increases the soybean crop in the conditions of Ternopil region by stimulating photosynthetic, growth and production processes.

Responses of Dry Bean to 2,4-D Ester Applied Preplant and Preemergence

Six field studies were completed in Ontario (during 2016 to 2018) to assess the tolerance of adzuki, kidney, small red and navy bean to 2,4-D ester at 528 or 1056 g·ai·ha-1 applied 14, 7 and 1 day before seeding (PP) and 3 days after seeding (PRE). 2,4-D applied PP or PRE caused as much as 4%, 6%, 7% and 8% injury in adzuki, kidney, small red and navy (white) bean, respectively. There was an increase in bean injury as the preplant interval decreased. At 1 WAE, 2,4-D applied at 1056 g·ai·ha-1 14, 7 and 1 day PP and 3 days after seeding caused up to 6%, 10%, 18% and 5% visible bean injury, respectively. The level of injury decreased over time with minimal bean injury (0 to 3%) at 8 WAE. Bean stand counts were similar to the non-treated control with 2,4-D applied at various timings except at 1 day PP when 2,4-D at the 2X rate decreased bean stand 13%. There was up to 23% and 43% decrease in bean dry weight with 2,4-D applied PP at 528 and 1056 g·ai·ha-1 7 and 1 day PP, respectively. Bean height (6 WAE) was not affected by 2,4-D applied at various timings except at 1 day PP when 2,4-D (1056 g·ai·ha-1) decreased bean height 10%. Additionally, there was no effect of 2,4-D treatments on bean maturity or yield. Based on these results, the safest times to apply 2,4-D are 14 days before seeding or PRE. Injury was higher when 2,4-D was applied 7 and 1 day PP. Injury was lower in adzuki bean compared to kidney, small red or navy bean.

English

A total of six field trials were conducted over a three-year period (2009 to 2011) to determine the tolerance of white and adzuki bean to pendimethalin plus reduced doses of imazethapyr applied preplant incorporated (PPI) in Ontario, Canada. There was minimal injury in white and adzuki bean with pendimethalin, imazethapyr and the tankmix of pendimethalin plus imazethapyr applied PPI at Harrow and Ridgetown. In contrast, at Exeter in 2009 and 2010, pendimethalin caused as much as 5 and 8% injury; imazethapyr caused as much as 18 and 5% injury; and the tankmix of pendimethalin plus imazethapyr caused as much as 20 and 14% injury in white and adzuki bean, respectively. Generally, the tank mixture of pendimethalin at 1080 or 2160 g ai ha-1 and imazethapyr at 37.5 g ai ha-1 had no adverse effect on height, biomass, seed moisture content and yield of white and adzuki bean. In white bean, the tank mixture of pendimethalin at 1080 or 2160 g ai ha-1 plus imazethapyr at 75 or 150 g ai ha-1 resulted in a decrease in height, biomass, and yield of white bean in some environments. In adzuki bean, the tank mixture of pendimethalin at 1080 g ai ha-1 plus imazethapyr at 37.5, 75 or 150 g ai ha-1 did not have any adverse effect on height, biomass, seed moisture content or yield. However, when the rate of pendimethalin was increased to 2160 g ai ha-1 in a tank mixture with imazethapyr at 37.5, 75 or 150 g ai ha-1, a decrease in adzuki bean height and biomass was observed but there was no effect on seed moisture content or yield. Based on this study, there is an adequate margin of crop safety for pendimethalin at 1080 g ai ha-1, imazethapyr at 37.5 g ai ha-1, and the tankmix of pendimethalin plus imazethapyr at 1080 + 37.5 g ai ha-1 applied PPI in white and adzuki bean.   Key words: Imazethapyr, navy bean, pendimethalin, Phaseolus vulgaris, Vigna angularis.

Tolerance of mung bean to postemergence herbicides

There are a limited number of postemergence (POST) herbicides available for weed management in mung bean production in Ontario. Five field studies were conducted in 2010, 2011 and 2012 near Exeter, Ontario and in 2011 and 2012 near Ridgetown, Ontario to determine the tolerance of mung bean to fomesafen, bentazon, bentazon + fomesafen and halosulfuron applied POST at the 1X and 2X proposed manufacturer’s recommended rate. Bentazon caused 5%-29%, 4%-31%, and 2%-18% injury, fomesafen caused 3%-17%, 1%-7%, and 0%-6% injury, bentazon + fomesafen caused 6%-40%, 4%-37%, and 1%-20% injury, and halosulfuron caused 13%-65%, 8%-75%, and 5%-47% injury in mung bean at 1, 2, and 4 weeks after treatment (WAT), respectively. At Exeter, fomesafen had no adverse effect on height of mung bean but bentazon, bentazon + fomesafen and halosulfuron decreased mung bean height as much as 5% compared to the untreated control. At Ridgetown, there was no decrease in mung bean height due to the herbicides applied. Fomesafen had no adverse effect on shoot dry weight of mung bean but bentazon, bentazon + fomesafen and halosulfuron decreased shoot dry weight of mung beans as much as 43%, 47%, and 57%, respectively. Fomesafen, bentazon, bentazon + fomesafen and halosulfuron had no adverse effect on the seed moisture content and seed yield of mung bean with the exception of halosulfuron applied POST at 70 g ai ha-1 which increased seed moisture content 0.4% at Exeter and 1.4% at Ridgetown and decreased yield 16% at Exeter compared to the untreated control. Based on these results, there is not an adequate margin of crop safety for bentazon, bentazon + fomesafen and halosulfuron applied POST in mung bean. However, there is potential for fomesafen applied POST at the proposed manufacturer’s rate of 240 g ai ha-1 in mung bean production.

Response of dry beans to halosulfuron applied postemergence

Soltani, N., Shropshire, C. and Sikkema, P. H. 2012. Response of dry beans to halosulfuron applied postemergence. Can. J. Plant Sci. 92: 723–728. Four field trials were conducted over a 2-yr period (2009 and 2010) at Exeter and Ridgetown, Ontario, to evaluate the tolerance of adzuki, black, cranberry, kidney, otebo, pinto, Small Red Mexican and white beans to halosulfuron applied postemergence (POST) at 35 and 70 g a.i. ha−1. All treatments including the non-treated control were maintained weed free during the growing season. Halosulfuron applied POST caused as much as 73, 7, 13, 12, 12, 11, 11 and 9% injury in adzuki, black, cranberry, kidney, otebo, pinto, Small Red Mexican (SRM) and white beans, respectively. Halosulfuron applied POST reduced adzuki bean height as much as 52 and 70% at Exeter and Ridgetown, respectively. Plant height was not affected in the other market classes of dry bean evaluated. Halosulfuron POST reduced shoot dry weight of adzuki bean 68% at both rates evaluated. Otebo and SRM bean shoot dry weight were not affected when halosulfuron was applied POST at 35 g a.i. ha−1 but otebo bean shoot dry weight was reduced 12% and SRM bean shoot dry weight was reduced 14% at 70 g a.i. ha−1. Shoot dry weight of black, cranberry, kidney, pinto and white bean was not affected with either rate of halosulfuron. Seed yield of adzuki bean was decreased 58% at 35 g a.i. ha−1 and 68% at 70 g a.i. ha−1 with halosulfuron. White bean yield was not affected with halosulfuron applied POST at 35 g a.i. ha−1 but was reduced 9% at 70 g a.i. ha−1. Seed yield of black, cranberry, kidney, otebo, pinto and SRM bean was not reduced with either rate of halosulfuron. Based on these results, there is not an adequate margin of crop safety for halosulfuron POST in adzuki bean. However, there is potential for POST application of halosulfuron in black, cranberry, kidney, otebo, pinto, SRM and white beans.

Effects of Bacterial Strains and Chicken Manure on Orobanche crenata Infesting Faba Bean

A pot experiment was conducted to assess the effect of bacterial strains and chicken manure on broomrape in faba bean. Results displayed that all treatments reduced Orobanche emergence except the combinations of Rhizobial bacterial strain TAL 1399 and composted chicken manure at 35 g/pot. Among all treatments faba bean inoculated with TAL 1399 alone or in combinations with Bacillus megatherium var phosphaticum (BMP) or Azospirillum braziliense (Ab) plus chicken manure at 35 g/pot displayed no Orobanche emergence (above the ground) until the end of the experiment. However, Orobanche attachment was observed only when faba bean was inoculated with TAL 1399 plus BMP. Moreover, all treatments increased faba bean plant height and dry matter as compared to the control. Faba bean inoculated with bacterial strain TAL 1399 alone or in combination with chicken manure at 30 g/pot sustained the highest plant height as compared to infested or non infested control. They increased faba bean height by 17-19%. Furthermore, crop treated with TAL 1399 plus chicken manure at 30g/pot was significantly higher in root, shoot and total dry weight as compared to the control and other treatments. Results displayed that faba bean growth was improved, especially if soil was mixed with chicken manure. These treatments could offer a new environmentally safe procedure to manage broomrapes, using farm resources and hence improve the sustainability of crop management. It would also be an effective asset in organic farming.

Snap Bean (Phaseolus vulgaris) Tolerance to Halosulfuron PRE, POST, or PRE followed by POST

A field experiment was conducted in 1996 and 1997 to determine snap bean tolerance to halosulfuron based on crop injury, height, and yield. Halosulfuron was applied preemergence (PRE), postemergence (POST), and sequentially PRE followed by (fb) POST at 35, 53, and 70 g ai/ha, respectively. For comparison, a hand-weeded check was included. When data were averaged across years and halosulfuron rates, halosulfuron PRE, POST, and PRE fb POST provided similar yellow nutsedge control (74 to 82%) at snap bean harvest. Halosulfuron PRE resulted in 4% snap bean injury at harvest. Similarly, halosulfuron PRE fb POST resulted in 5% injury, while halosulfuron POST caused the most damage at 8%. Snap bean height at harvest was reduced 14% with halosulfuron POST compared to the weed-free check, with only 5 and 6% reduction caused by halosulfuron PRE and PRE fb POST, respectively. Halosulfuron POST reduced yield 39% compared to the weed-free check, while the PRE and PRE fb POST application timings produced yield similar to the check. When averaged across years and halosulfuron application timings, an increase in halosulfuron rate had no effect on yellow nutsedge control or snap bean yield. A linear trend was found for snap bean injury and plant height at harvest with snap bean injury increasing with an increase in halosulfuron rate while snap bean plant height decreased with an increase in halosulfuron rate. Application of halosulfuron PRE is the safest means to control yellow nutsedge in snap bean in North Carolina.

Potencial de espécies vegetais para a remediação do herbicida trifloxysulfuron-sodium

Este trabalho teve como objetivo avaliar a eficiência de espécies vegetais na remediação do herbicida trifloxysulfuron-sodium em solos, utilizando o feijão (Phaseolus vulgaris) como planta indicadora. Os tratamentos foram compostos pela combinação entre as espécies Calopogonium mucunoides, Crotalaria juncea, Crotalaria spectabilis, Vicia sativa, Cajanus cajan, Canavalia ensiformis, Medicago sativa, Dolichus lab lab, Penisetum glaucum, Stylosantes guianensis, Mucuna deeringiana, Mucuna cinereum, Mucuna aterrima, Raphanus sativus e Lupinus albus. Todas as espécies foram semeadas em vasos no dia seguinte à aplicação do trifloxysulfuron-sodium em três doses (0,00; 3,75; e 15,00 g ha-1). Após 80 dias da semeadura, as espécies vegetais foram cortadas na altura do coleto e a parte aérea destas descartada. A seguir, foi realizada a semeadura do feijão (cultivar Pérola). Aos 45 dias após a emergência das plantas de feijão avaliaram-se a altura e a massa seca da parte aérea das plantas. Melhor eficiência na descontaminação do trifloxysulfuron-sodium em solo foi obtida pelas espécies M. aterrima e C. ensiformis.

Herbicide Tolerance of Lima Bean (Phaseolus lunatus) in Ontario1

Lima bean cultivar ‘Improved Kingston’ was evaluated for sensitivity to herbicide treatments in a field experiment, conducted from 1999 to 2001 in Ontario. Crop was evaluated for visual injury at 7, 14, and 28 d after emergence following preemergence (PRE) applications of metolachlor (1,600 and 3,200 g ai/ha) and imazethapyr (75 and 150 g ai/ha). Crop visual injury to postemergence (POST) applications of imazamox + fomesafen (25 + 200 g ai/ha and 50 + 400 g ai/ha) and quizalopfop-P (72 and 144 g ai/ha) was evaluated at 7, 14, and 28 d after treatment. Plant height and crop yield were also assessed. The imazamox + fomesafen mixture caused significant visual injury and tended to decrease lima bean height and yield. Despite some initial injury observed in the metolachlor, imazethapyr, and quizalofop-P treatments, yield was not significantly decreased. Because of their margin of crop safety, metolachlor applied PRE at 1,600 g/ha, imazethapyr applied PRE at 75 g/ha, and quizalofop-P applied POST at 72 g/ha hav...

Tolerance of cranberry beans (Phaseolus vulgaris) to soil applications of s-metolachlor and imazethapyr

There is little information on the tolerance of cranberry beans to preplant incorporated (PPI) and preemergence (PRE) applications of s-metolachlor and imazethapyr, eithe r alone or in tank mix combination, for selective weed control in cranberry beans in Ontario. Tolerance of two cranberry bean cultivars, Hooter and SVM Taylor, to PPI and PRE applications of s-metolachlor, imazethapyr and their tank mix combination at the label rate (1×) and twice the label rate (2× ) were studied at two Ontario locations (Exeter and Ridgetown) in 2001 and 2002. There were no differences between the two cultivars in their responses to the herbicide treatments. PPI and PRE applications of s-metolachlor alone at the 1× and 2× rate had no effect on visual crop injury and no negative effect on plant height, dry weight and yield compared to the control. The PPI and PRE applications of imazethapyr at the 1× rate did not result in significant visual crop injury, and had no negative effect on bean height and dry weight, but at the 2× rate there was significant visual crop injury, a decrease in height with the PPI application and decreased dry weight with PPI and PRE applications. No negative effect o n cranberry bean yield was observed with the application of imazethapyr at either the 1× or 2× rates. The PPI and PRE applications of the tank mix of s-metolachlor plus imazethapyr at the 1× rate did not result in significant visual crop injury or decreases in bean plant height or dry weight. At the 2× rate, there was significant visual crop injury, a decrease in bean plant height with PPI and PRE applications and decreased dry weight with the PPI application. The tank mix of s-metolachlor plus imazethapyr at the 1× rate had no effect on yield, but the PPI application at the 2× rate caused a decrease in yield at 1 of the 4 site-years. Key words:

Dry Edible Bean (Phaseolus vulgaris) Response to Imazethapyr

Imazethapyr at 0.07 and 0.10 kg ai ha-1applied preplant incorporated (PPI), preemergence (PRE), and postemergence (POST) was evaluated at two locations in 1988 and 1989 for safety to dry edible beans. Bean stunting, leaf crinkling, and interveinal chlorosis were evident from imazethapyr and varied from 1 to 57%. Imazethapyr significantly reduced bean height and delayed maturity. PPI and POST applications of imazethapyr at 0.07 and 0.10 kg ha-1did not reduce bean seed yields compared to yields of the untreated control. Bean cultivar by herbicide interactions were significant for bean injury but varied with year and location.

Nutrient and growth response of pinto bean to foliar‐applied herbicides and soil temperatures

Abstract Two soil temperatures, 19 ± 1 and 27 ± 3C affected some nutrient concentrations in roots, stems and leaves of ‘U. I. III’ pinto bean (Phaseolus vulgaris), but did not affect overall plant morphology. Acifluorfen (5‐[2‐chloro‐4‐(trifluoromethyl)phenoxy]‐2‐nitrobenzoic acid) at 0.84 kg ai/ha reduced N, P, K, Ca, Mg, Cu, Mn and Zn levels in each of the 3 plant tissues and also reduced pinto bean height, leaf area, root, leaf, and stem weight, and nodule wet weight compared to the nonherbicide‐treated controls. Bentazon [3‐(l‐methylethyl)‐(lH)‐2,l,3‐benzothiadiazin‐4(3H)‐one‐2,2‐dioxide] and sethoxydim ((2‐[l‐(ethoxyimino)butyl]‐5‐[2‐(ethylthio)propyl]‐3‐hydroxy‐2‐cyclohexen‐l‐one)) generally did not affect pinto bean growth or nutrient accumulation.

Snap Bean (Phaseolus vulgaris) and Common Lambsquarters (Chenopodium album) Response to Acifluorfen

Field studies were conducted for 3 yr to determine the foliar activity of acifluorfen {5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid} for control of common lambsquarters (Chenopodium albumL. # CHEAL) in snap beans (Phaseolus vulgarisL. ‘Provider’ in 1983 and 1985 and ‘Green Crop’ in 1984). Control of 1 to 7 cm tall common lambsquarters varied between 75 and 100% with 0.28 kg ai/ha acifluorfen and frequently increased linearly with increases in acifluorfen rates to 0.84 kg/ha. Snap bean injury occurred each year and in 1985 was influenced by acifluorfen rate, stage of snap bean growth, and surfactant. Snap bean yields in 1983 were reduced linearly with increases in acifluorfen rates and in 1985 were reduced more from applications at the 1- to 2-trifoliolate leaf stage than at the 4- to 8-trifoliolate leaf stage. In the greenhouse, reductions in snap bean height from acifluorfen were related to application timing, surfactant and cultivar. Fresh weight reduction of snap beans was highest with the cultivar ‘Green Crop’ but was increased to both cultivars by early application timing and the addition of surfactant to the spray mix.