Downy mildew of Basil is here to Stay

Downy Mildew Close-up

Downy Mildew Close-up

Downy Mildew Spore Growth on Basil Leaves

Downy Mildew Spore Growth on Basil Leaves

Downy mildew of basil is a new destructive disease that appears to be here to stay. In the first years of its appearance in the U.S., complete crop losses occurred for some growers because basil leaves with any mildew are unmarketable. Applying fungicides frequently and starting before first symptoms are considered necessary to control basil downy mildew effectively.

“Sweet basil (Ocimum basilicum L., Fam. Lamaiaceae) is the most commercially important annual culinary herb crop grown in the United States. Sweet basil is grown for culinary use for both fresh and dry consumption and as a source of essential oil and oleoresin for manufacturing perfumes, food flavors, and aromatherapy products.

Basil downy mildew… is a new disease of basil in the United States. …In the United States, the pathogen was first discovered in Florida in the fall of 2007. Since that time, basil downy mildew has been found throughout the eastern United States and in regions of commercial basil production in the Midwest and California.

Once basil plants become infected and develop symptoms, they are no longer marketable as a fresh product. …Currently, there is no known resistance or tolerance to basil downy mildew leaving 100% of the sweet basil acreage in the eastern United States vulnerable to the pathogen. Without adequate chemical control options and genetic resistance, basil downy mildew has the potential to destroy basil production in the eastern United States and in all other areas where basil is being produced.

Selection criteria such as foliar morphology, plant architecture as well as the presence of secondary metabolites and other factors that provide a less favorable microenvironment to the pathogen need to be examined as potential avenues for developing downy mildew-resistant sweet basil cultivars. Until this can be achieved, basil growers will have to rely on multiple applications of the few commercial fungicides currently registered to produce a marketable crop. Additionally, for organic basil growers, control of basil downy mildew will be even more challenging because there are fewer approved products labeled for organic use.”

Authors: Wyenandt, C. A., et al.
Affiliation: Department of Plant Biology and Pathology, Rutgers University
Title: Susceptibility of basil cultivars and breeding lines to downy mildew (Peronospora belbahrii)
Source: HortScience. 2010. 45(9):1416-1419.

To Increase Income and Competiveness, Public Policy Should Educate African Maize Farmers About the Benefits of Using Herbicides

Weedy Maize Field: Africa

Weedy Maize Field: Africa

Maize consumption is a major source of calories for millions of people in Sub-Saharan Africa. Within the next few decades, the majority of people in Sub-Saharan Africa will be living in cities. Countries in eastern and southern Africa are increasing imports of staple foods, including maize. In order to be competitive, African farmers need to reduce the cost of producing a unit of maize. Herbicide adoption would greatly reduce costs of growing maize and lead to greater yields and farmer income and competiveness.

“Rural smallholder production remains highly labor-intensive. On average, family labor accounts for 62% of the total cost of maize production in Zambia’s small- and medium-scale farm sector. Promoting the identification and adoption of practices and technologies that save labor and/or identifying labor-productivity-enhancing technologies through research and development will therefore help to make Zambian maize more competitive and allow farmers to maintain profitability even at lower producer prices.

Although only 3% of fields had herbicides applied, regression results suggest the benefits of its use are quite high. All else equal, applying herbicides increases gross margin between ZMK 363,700 to ZMK 376,300 per hectare planted… The magnitude of this effect is fairly large compared to the national average margin of ZMK 1,108,542 (in other words, at the mean, herbicide use would increase gross margins by roughly a third). …these results indicate that public policy measure should be considered to educate farmers about the benefits of herbicide application, as its contribution to smallholder income growth and regional competitiveness may be comparable to and highly synergistic with increased fertilizer use.”

Authors: Burke, W. J., et al.
Affiliation: Zambia Food Security Research Project (FSRP)
Title: The cost of maize production by smallholder farmers in Zambia
Source: Food Security Research Project. Working Paper 50. March 2011. Available at: 

Organic Cocoa Growers Likely to Switch to Conventional Production if Financing of Inputs is Made Available

Weedy Cocoa: Ghana

Weeding Cocoa: Ghana

There are very few certified organic cocoa growers in Africa. The risks of trying to grow an organic crop are great. Many of these growers choose to grow organically because they lack financial resources to purchase inputs including pesticides. With financing of inputs, many of the current organic growers are likely to switch to use of conventional methods with pesticides due to greater yields, income and less risk.

“…the total market share of organically grown cocoa is still relatively very small and accounted for less than 0.5% of the total production in 2002 to 2005.

For producers who cannot afford inorganic inputs and who currently grow organic cocoa, there is a large amount of risk (both in price and in yield) involved with an estimated 30% lower yield compared with conventional (inorganic) production.

The obvious challenge for producers to produce conventionally is to obtain credit up front to purchase inorganic inputs. Given the advent of organizations like the Cocoa Abrabopa Association (CAA) established in 1998 in Ghana, credit is becoming more accessible to producers.

The current organic producers, who are constrained to do so because of a lack of microfinance opportunities to buy conventional inputs (fertilizer, fungicide, etc.), would probably switch to conventional if financing for said inputs became available, say through a microfinance program. Thus, an unintended impact of a microfinance program might be to lead to lower levels of current organic production.”

Authors: Mahrizal, L., et al.
Affiliations: Department of Agricultural Economics and Agribusiness, University of Arkansas
Title: Necessary price premiums to incentivize Ghanaian organic cocoa production: a phased, orchard management approach
Source: HortScience 47(11)1617-1624. 2012.

Herbicide Use on Cotton Farms Could Greatly Increase Income of Farm Families in Africa

African Cotton Herbicide Experiment

African Cotton Herbicide Experiment

The income of family farms growing cotton in Africa is low largely due to the small size of farms- about one hectare. A major reason that farm size is small is because fields are weeded by hand and there usually is not enough family labor to weed more than one hectare. With use of herbicides, the need for labor is reduced dramatically and individual cotton farms would be able to significantly increase their acreage and incomes.

“Under rainfed agricultural production, common throughout most of Africa, labor bottlenecks at planting and weeding times often critically constrain farm output. During the four to six week period following the first rains, farmers must prepare their soil, plant and conduct the critical first weeding.

Under these circumstances, early season labor constraints, particularly during the first weeding, set an upper bound on the cropped area a family can manage using only household labor. For the average farm household in central Zambia, with five family members, peak-season labor bottlenecks limit the area they can cultivate under conventional hand hoe tillage to about 1 hectare.

In Zambia, herbicide application, instead of weeding with a hand hoe, cuts peak season labor requirements in half.

When combined with dry season land preparation, this reduction in peak season labor requirements enables farm households to crop 2.7 hectares of land under hand hoe cultivation using only household labor. As a result, hand hoe farmers can increase their income from these three crops to 2.9 million Kwacha ($620) per year, triple what they can earn under conventional hand hoe agriculture…

This suggests that cotton company inclusion and financing of one round of herbicides in their cotton packs could potentially raise cotton production and household income considerably.”

Authors: Steven Haggblade and Christina Plerhoples
Affiliations: Department of Agricultural Food and Resource Economics at Michigan State University
Title: Productivity impact of conservation farming on smallholder cotton farmers in Zambia
Source: Food Security Research Project. Working Paper 47. July 2010. Available at: 

California Avocado Production Would be 82 million Pounds Lower with Conversion to Organic Practices

New Orchard Weeds

New Orchard Weeds

California farmers produce 550 million pounds of avocados annually. 8% of the avocado acres are managed with organic production practices. A recent economic analysis by the University of California shows why so few avocado acres are organic. Even though organic avocados receive a price premium, lower yields (15% lower) means lower profits than avocados grown with chemical inputs. The 15% lower yields would mean a loss of 82 million pounds of avocados if all the California avocado growers switched to organic practices. Weeds are the biggest problem for organic avocado growers.

“Profitability estimate of organic avocados in these counties is lower than avocados produced conventionally. Though organic avocados are considered to receive $0.20 more per pound than conventional avocados, organic avocado production shows lower yield than the conventional production.

Based on our discussions with growers and the UCCE farm advisor, organic yield is considered lower than the conventional production. In this study, organic avocado yield is estimated at 15% lower than the conventional yield.”

Author: Etaferahu Takele, et al.
Affiliation: Area Farm Advisor, Agricultural Economics/Farm Management, University of California Cooperative Extension (UCCE) Southern California
Title: Avocado sample establishment and production costs and profitability analysis san diego and riverside counties, 2011 organic production practices
Source: University of California Cooperative Extension. 2013.

Herbicides Have Helped Stabilize Wheat Production in Kazakhstan

Kazakhstan ranks in the top 10-15 wheat-producing countries in the world depending on weather conditions (drought is a significant factor 2 out of 5 years). Kazakhstan is a major exporter of wheat with about 4 million tons exported annually. Weeds are a key limiting factor in Kazakhstan’s wheat production; however, recent increases in herbicide use have significantly reduced yield losses.

“Although weather remains the single most important determinant for grain yield in Kazakhstan, improvements in crop management practices fueled by the growing State subsidies have contributed to the recent increase and relative stabilization in wheat yield.”

“According to specialists at the Ministry of Agriculture, nearly half the total cultivated area in Kazakhstan is infested with weeds, including 2.5 million hectares infested with black oats. Between 1999 and 2002, farmers applied virtually no herbicides for the control of black oats on approximately 320,000 hectares. In 2003, treatment expanded to 1.0 million hectares thanks to government subsidies of about US$2 million which reduced farmers’ cost of chemicals by 30 to 40 percent. Herbicide subsidies increased to nearly US$3 million in 2004 and the treated area grew to about 1.4 million hectares. Specialists report that weed infestation has decreased by about 15 percent every year since the anti-black oat campaign was launched.”

Author: Mark Lindeman
Affiliation: USDA Foreign Agricultural Service
Title: Kazakhstan Wheat Production: An Overview
Available at:

New Rice Planting Method Makes Herbicides Necessary in Pakistan

Traditionally, rice has been planted manually in flooded fields in Pakistan. This method of planting requires large amounts of water and a high level of labor. The sustainability of this system is threatened by severe labor and water shortages. Research has focused on direct machine planting of rice seeds in non-flooded soil. However, weeds flourish when the soil is not flooded making herbicides a necessary component of the new planting system.

“An increasing water crisis, as well as the unavailability and high cost of labor, in Pakistan has forced rice-growers to plant rice directly into the field. However, severe weed infestation causes disastrous effects on the productivity of this rice system. In this study, three herbicides were evaluated for weed control in direct-planted rice on a sandy loam soil. Weedy check and weed-free plots were established for comparison. Weed infestation decreased the rice yield by 75.2%. However, the application of herbicides suppressed the weed infestation, with a simultaneous increase in the rice yield.” 

Author: Khawar Jabran, et al.
Affiliation: Ayub Agricultural Research Institute, Faisalabad, Pakistan
Title: Application of bispyribac-sodium provides effective weed control in direct-planted rice on a sandy loam soil.
Publication: Weed Biology and Management. 2012. 12:136-145.

Mr Bittman, Reducing Herbicide Use on Farms is Not Simple

The New York Times writer Mark Bittman writes glowingly about a recent study¹ that reported on an Iowa experiment in which crop yields were maintained while herbicides to control weed populations were reduced (“A Simple Fix for Farming,” NYT,10-21-2012)². Bittman concludes that, “there was only upside—and no downside at all” in this study.  Rhetorically, Bittman asks, “Why wouldn’t a farmer go this route?”. That question was studied by rural sociologists from the University of Missouri and their findings³ show that it’s not so simple to reduce herbicide use—there are serious downsides. The study that Bittman cites reduced herbicide use by switching from spraying the entire field (broadcast spraying) to spraying just down the row of plants (banded spraying) and using cultivation to kill weeds between the rows. This technique of “banding” the herbicide spray in combination with tillage was widely-used several decades ago, but farmers changed to spraying the entire field without the need to cultivate. The sociologists asked farmers why they abandoned the practice and if they would consider using it again. The answer was…

“Operators are not rejecting the practice due to a perceived lack of knowledge of how the practice works or dissatisfaction with reductions of pesticide use or of water quality risks. … The reasons for discontinuing banding related to difficulties of implementing and maintaining the practice and consequently, potential negative impacts on yields and profits. Banding requires two major tasks—the initial banding and the subsequent two (or sometimes three) cultivations between the rows. In effect, it substitutes time, labor, and equipment for out-of-pocket pesticide costs and thus has important ripple effects in terms of time, labor, management, flexibility, and individual control.”

“Banding tasks need to be done on a timely basis; a shortage of labor during windows of cultivation opportunity can mean the growth of weeds to the point where they inhibit crop progress and effective cultivation, and thus decrease yields. Some operators report inabilities to find labor. We have ample evidence of the decline of availability of hired labor in most rural communities… Those people willing to custom cultivate are usually farmers themselves. And home farm demands, overextended commitments, and bad weather and machinery breakdowns can easily combine to delay or postpone custom cultivation beyond optimal periods.”

“Cultivation of large banding acreages requires continuous weeks of effort. Although such commitments were common practice before the broadcast use of herbicides, farmers who rejected banding criticize cultivation as too time-consuming, intrusive into other needed work, ineffective, and certainly one of those jobs they were not eager to resume.”

“Some farmers have purchased banding-related machinery or attempted to experiment with the practice only to find it too difficult to incorporate into tight farming schedules. … Effective cultivation also creates dependency on other external factors. In years with a particularly wet spring and early summer, for example, cultivation has to be postponed.”

“In summary, operators who abandon banding do so not because of water quality issues or lack of knowledge or even additional costs; they drop it because of time and labor requirements, custom labor constraints, loss of control over operations, and potential risks to yield and profitability. … In essence, while banding may work for water quality, it is not working for most farmers.”

¹Authors: A.S. Davis*, J.D. Hillª, C.A. Chaseº, A.M. Johannsº and M. Liebmanº.
Affiliations: *USDA ARS; ªUniversity of Minnesota; ºIowa State University
Title: Increasing cropping system diversity balances productivity, profitability and environmental health.
Publication: PLoS ONE. 2012. 7(10): e47149.

²Author: Mark Bittman
Headline: A Simple Fix For Farming
Publication: The New York Times. October 21, 2012.

³Authors: J.S. Rikoon, R. Vickers and D. Constance
Affiliation: Department of Rural Sociology, University of Missouri-Columbia.
Title: Factors affecting initial use and decisions to abandon banded pesticide applications.
Publication: Agricultural Research to Protect Water Quality Conference Proceedings. 1993. February 21-24, Minneapolis, Minnesota.

Organic Rice Growing Reduced Average Yield of Rice in Texas

Eight percent of the rice acreage in Texas is managed organically. These organic acres have much lower yields than conventionally grown acres. As a result, the overall yield of rice in Texas has declined.

“Organic rice acreage accounted for ca. 8% of the state’s total rice production. Organic rice fields typically yield ca. 30-40% of conventional commercial yields, this brought down the statewide average rice yields. An organic rice crop that yields 40% of the yield of a conventionally [grown] crop is equal to a 60% yield decrease. Multiplying a 60% yield decrease by 8% of the acreage is equal to a 5% drop in the average yield per acre.”

Author: L.T. Wilson
Affiliation: Texas A&M University
Title: From the Editor… Changes in Texas Rice Production
Publication: Texas Rice. 2007. Winter:2.

National Academy of Sciences Credits Pesticides with Improving American Diet

Americans take for granted a plentiful, inexpensive daily supply of fruit and vegetables. This bounty has come about due to increased production throughout the county as a result of pesticide use – a point made by the National Academy of Science…

“Pesticides are used widely in agriculture in the United States. When effectively applied, pesticides can kill or control pests, including weeds, insects, fungi, bacteria, and rodents. Chemical pest control has contributed to dramatic increases in yields for most major fruit and vegetable crops. Its use has led to substantial improvements over the past 40 years in the quantity and variety of the U.S. diet and thus in the health of the public.

Authors: National Research Council
Affiliation: National Academy of Sciences
Publication: Pesticides in the Diets of Infants and Children. 1993. National Academy Press, Washington, DC.