The Importance of Pendimethalin Herbicide in Greece


Greek Cotton Field

Pendimethalin is normally used to control weeds on about 85% of the cotton and onion farms in Greece. During the last decade, the number of approved herbicides has drastically declined in Europe, leaving farmers with less choices and high weed control costs. Researchers at Aristotle University recently summarized the potential effects on Greek farmers if use of pendimethalin were to be stopped as a result of EU regulatory action.

“This work aims to determine the current state of experts’ knowledge, attitudes and beliefs regarding pendimethalin use in three crops (cotton, onion, processing tomato). The survey is focused on experts’ perceptions towards the necessity of pendimethalin in weed control, the advantages and disadvantages of pendimethalin and the probable impacts of pendimethalin withdrawal due to EU regulation or stoppage in manufacturing.

Any action of stoppage or withdrawal of pendimethalin from the market will bring about devastated effects on the farmers and crops, mainly due to lack of effective substitutes or herbicide combinations. The most significant impact, in case of pendimethalin withdrawal, would be a surge in production cost, since farmers must apply more costly and perhaps less effective weed control techniques (hoeing, covering land with plastic and using other combinations of herbicides).

…a Greek farmer hardly can harvest cotton without chemical weed control. Also, they stated that hardly can vision the possibility to cultivate onion, in the Viotia area, and cotton in Thessaly region without herbicide availability, since cost effective alternatives cannot being foreseen.

Then, considering the withdrawal effects of the use of pendimethalin in a regional level, the growers of cotton in Thessaly will lose a total of approximately €16.4 million of their gross production value and a total of approximately €7.3 million of their net revenues. …Finally, in a national level the growers of cotton in whole Greece will lose a total of approximately €42.8 million of their gross production value and a total of approximately €19.1 million of their net revenues.”

Authors: Mattas, K., et al.
Affiliations: Aristotle University of Thessaloniki.
Title: Economic assessment of Pendimethalin herbicide use in selective crops (cotton, processing tomato & onion).
Source: Aristotle University of Thessaloniki Working Papers No 166116 Available:

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: 

Century-Old Cotton Rot Problem Solved with New Fungicide

Root Rot

Root Rot

Cotton Root Rot is a highly destructive disease caused by a soil borne fungus in the southwestern U.S. The fungus penetrates the roots of the cotton plant and blocks the flow of water from the roots to the leaves for transpiration, causing the leaves to wilt. Plants infected early in the growing season die before bearing fruit, whereas infections occurring at later plant growth stages reduce cotton yield and quality. Cotton Root Rot has plagued the cotton industry for more than 100 years. Despite decades of research, effective methods to control the disease were lacking until recently……

“On February 2, 2012, the US Environmental Protection Agency approved a section 18 label for Texas for the fungicide Topguard (flutriafol), to control root rot of cotton (CRR) caused by the soil borne fungus, Phymatotrichopsis omnivore.

CRR is the major yield-limiting disease in many of the cotton-production areas of Texas, causing annual losses exceeding $29 million. Yield losses to individual growers vary greatly, but can range up to 100%.

CRR has been a problem of Texas cotton since the 19th century. The first experiments on control of this disease were published in 1888 and in spite of extensive research efforts since then, there has been no substantial progress, until our recent identification of flutriafol as an effective fungicide. In some of our field trials with strong disease pressure, the yield was increased by as much as 60%. The application is made as a liquid spray to the soil around the seed at planting.”

Authors: Department of Plant & Microbiology Bioenvironmental Sciences
Affiliation: Texas A&M University
Title: Breakthrough against cotton root rot

Organic Cotton Discontinued in Uganda – Due to Damage to the National Economy!

Cotton is considered one of the most strategic commodities in Uganda for increasing household income, creation of employment, industrialization and poverty alleviation. In 1995 the Swedish International Development Agency began promoting organic methods of growing cotton in Uganda. The area under organic management expanded rapidly. Farmers were attracted to organic cotton because the promoters promised a premium price. Then, the reality of trying to grow cotton without chemical pesticides sunk in, shown below in remarks from a presentation by Jolly Sabune, Managing Director of the Cotton Development Organization.

  • During 2007/8, the en-mass introduction of organic caused over 68% drop in yields in the organic areas.
  • National cotton production also dropped by 50% from 134,000 bales in 2006/7 to 66,500 bales in 2007/8.
  • Organic promoters were sabotaging government efforts of increasing cotton yields by de-campaigning use of the effective conventional pesticides.
  • Following the sharp decline in production due to en-mass introduction of organic cotton, the government of Uganda decided that organic cotton promoted in the manner seen during 2007/8 was entrenching poverty rather than alleviating it and would therefore not be accepted.
  • Anyone who wants to support small-scale farmers in cotton must therefore promote conventional cotton production.

Author: Jolly Sabune
Affiliation: Cotton Development Organization
Title: Organic Cotton Production: Uganda’s Experience. Available at:

Jimmy Carter Lived the Weed Nightmare

Our 39th President, Jimmy Carter, grew up on a peanut and cotton farm long before herbicides were available to manage weeds. In his autobiography, President Carter recounts the nightmare of trying to control weeds with tractors and hand labor.

“Our part of Georgia receives about fifty inches of rain during an average year, mostly during the spring and early summer… However, depending entirely on draft animals and hand labor, small variations in the rain pattern could be devastating. … The dry ground permitted the mule-drawn cultivating plows and hoes to restrain the ever-encroaching weeds and grass. However, when no plowing was possible because of several successive days of rain, the noxious plants were uncontrollable. Something like the terrible creeping and oozing things in horror movies, Bermuda grass, coffeeweed, cocklebur, Johnsongrass, beggar-lice, and nut grass would emerge from what had been a cleanly cultivated field, and in a few days our entire crop of young peanuts and cotton could be submerged in a sea of weeds. Often, despite the most heroic efforts by the best farmers, parts of the crop would have to be abandoned. Although partially salvaged, the remaining young plants were heavily damaged by the aggressive plowing and hoeing. During these rainy times, Daddy would pace at night, scan the western skies for a break in the clouds, and scour the community, often far from our own farm, to recruit any person willing to hoe or pull up weeds for day wages.”

Author: Jimmy Carter
Publication: An Hour Before Daylight: Memories of a Rural Boyhood. 2001. Simon & Schuster, New York.

Heavy Thrips Infestations in Virginia and North Carolina Cotton

Thrips have many hosts, including grasses, grains and alfalfa. Large populations often develop on these hosts and fly into cotton fields when the cotton seedlings are developing. Thrips feeding causes severe deformation and stunting of the developing cotton leaves. The Upper Southeast cotton region (Virginia and North Carolina) could be designated “Thrips Central” for the Cotton Belt. Jack Bacheler, a North Carolina Extension Entomologist, explains…

“With the exceptionally warm winter and good moisture levels, at this point it looks like thrips flights into cotton should be both large and early this year. … Our region has earned the distinction of having the highest levels of thrips and greatest potential damage to seedling cotton of anywhere in the U.S. In some tests, with the help of a microscope, we sometimes count as many as 200 to 500 thrips per 5 seedlings! That’s a “ton” of thrips, especially if seedlings are unprotected. So it’s probably not a surprise that Virginia and North Carolina have the highest ratio of surrounding host vegetation to small average cotton field size.”

“Over the past eight years, more than 85 percent of our cotton acreage has been over-sprayed [i.e. sprayed over] following a seed treatment. With the potential for thrips damage lasting up to 5 or 6 weeks after planting and seed treatments varying from about 2 to 3 weeks in their activity, a high percentage of foliar follow-up treatments for thrips is not surprising.”

Author: Jack Bacheler
Affiliation: North Carolina Extension Entomologist
Title: Heavy thrips populations anticipated.
Publication: Southeast Farm Press, April 18, 2012. Available: