ISIS报告：转基因农作物在美国面临崩溃

ISIS Report 01/02/10

GM Crops Facing Meltdown in the USA

ISIS报告：转基因农作物在美国面临崩溃

翻译：Silence 校对：義成

文章来源：http://www.i-sis.org.uk/GMCropsFacingMeltdown.php

在转基因生物的中心地带，经遗传改造而具有耐受除草剂和抗虫性两类显著特性的主要农作物，正在被超级杂草和次生害虫破坏，农民也在为更多同样的败局而抗争；向有机耕作实践的根本性转变也许是唯一挽救之道。——侯美婉博士

请广泛传播，保持所有的链接不变，并交给贵国政府代表要求停止转基因农作物的种植，要求支持非转基因的有机农业！

两种显著特性涵盖了目前世界上商业化种植的所有的转基因（GM）农作物：耐受除草剂（HT）特性，因含有从一类土壤细菌－－根癌农杆菌（Agrobacterium tumefaciens）获得的5 -烯醇丙酮莽草酸3-磷酸合成酶（EPSPS）编码基因而对草甘膦除草剂不敏感；抗虫特性，由于含有一个或更多的从另一类土壤细菌－－苏云金芽孢杆菌(Bacillus thuringiensis)获得的毒素基因。在美国－－转基因生物的中心地带，商业化种植转基因作物开始于1997年左右，並在此后的许多年间迅速增加。截至目前，在美国三大主要农作物——大豆、玉米和棉花的耕种区域[1]（见表1），转基因作物已达85%-91%，其种植面积近171百万英亩。

伴随转基因农作物的生态定时炸弹已经渐行渐近，它即将被引爆。

耐受除草剂的农作物助长了除草剂的使用，导致抗除草剂杂草的产生，反过来又需要更多的除草剂。但越来越多的使用剧毒除草剂和除草剂混合物，没能阻止在耐受除草剂的农作物田中超级杂草的继续生长。同时，次生害虫如抗Bt毒素的牧草盲蝽，成为破坏美国棉花的最主要害虫。

杀不死的植物怪物

现在是“三脚树”的时代——这种三脚树不是指约翰·温德姆的科幻小说《三脚树时代》中提到的转基因植物，而是“杀不死的超级杂草”[2]。正如美国广播公司电视新闻曾报道，这种超级杂草是由于种植抗除草剂的转基因作物而被创造出来的。

电视新闻的现场是2009年10月阿肯色州的收获季节。表情严峻的农民和科学家正在布满巨藜的田间交谈，这种巨藜即使喷洒再多的草甘膦除草剂都死不了。一位农民在3个月内花了50万美元试图清除怪物杂草，仍然徒劳；联合收割机和手工工具对这些杂草都无能为力。据估计，在阿肯色州有100万英亩的大豆和棉花田中已大量滋生怪物杂草。

ABC新闻报道：超级杂草

长芒苋或藜是最可怕的杂草。它可长至7-8英尺高，耐高温和长期干旱，产生数千种子，并有可从农作物吸尽养分的发达根系。如果任其发展，在一年内将占领整个农田。

与此同时，在北卡罗莱纳州珀奎曼斯县，农民兼农业推广人员保罗·史密斯刚刚在他的田里发现可恶的杂草[3]，他也将不得不雇用移民队以手工除草。

预计这种抗除草剂杂草会侵入邻近的县。它早已产生针对至少三种其他类型除草剂的抗性。

抗除草剂的杂草并不是新鲜事。在北卡罗莱纳州有10种，全国有189种杂草对一些除草剂产生抗性。

北卡罗莱纳州立大学的退休农学教授、国家级杂草专家艾伦·约克说，“不太可能生产一种新型除草剂。”

抗草甘膦杂草的产生是由于广泛种植抗除草剂农作物

草甘膦是美国和世界上最广泛使用的除草剂。自20世纪70年代以来，它被孟山都公司以农达为商标名称和专利配方申请专利权并销售。随着抗除草剂农作物的种植而流行使用。美国农业部的数据表明，在主要农作物上的草甘膦的使用量在1994年至2005年间增长了15倍多[4]。据EPA（美国环保署）估计，在2000-2001年，每年1亿磅草甘膦用于草地和农场 [5]，在过去的13年里，它已应用于超过10亿英亩的农田里[6]。

抗草甘膦的杂草不久就出现了，就像很多杂草对以前使用的每一种除草剂产生了抗药性的情形一样。美国杂草科学学会公布在美国有9种杂草被确认抗草甘膦[6]；其中有普通豚草(Ambrosia artemisiifolia)，普通waterhemp（苋菜藤子）(Amaranthus rudis)，巨豚草（三裂叶豚草）(Ambrosia trifida)，毛灯盏细辛(Conyza bonariensis)，加拿大乍蓬(Conyza canadensis)，意大利黑麦草(Lolium multiflorum)，假高粱 (Sorghum halepense)，刚性黑麦草(Lolium rigidum)和帕默藜(Amaranthus palmeri)。

抗草甘膦超级杂草

在2004年年底，抗草甘膦的帕默藜首次出现在佐治亚州梅肯县，并已蔓延到佐治亚州其他地区以及南卡罗来纳州、北卡罗来纳州、阿肯色州、田纳西州、肯塔基州和密苏里州[7]。根据佐治亚大学杂草专家斯坦利·卡尔佩珀估计，佐治亚州有10万英亩农田严重布满了藜，有29个县现已证实藜是抗草甘膦的。 2007年，在梅肯县，1万英亩农田因抗草甘膦藜大量滋生而被抛荒。

据报道，孟山度公司技术开发部经理里克·科尔曾说，这样的问题是“可管理的”。他建议农民轮种并使用不同品牌的除草剂。孟山都的销售代表正在鼓励农民把草甘膦和以前使用的除草剂如2，4-二氯苯氧乙酸 （2,4-D）混合使用。2,4-二氯苯氧乙酸在瑞典、丹麦和挪威三个国家因与癌症、生殖和神经系统的损害有关而被禁用，它是1960年代在越南使用的橙剂的组分之一。

据报道佐治亚州的农民已改种传统的非转基因作物。

佐治亚大学的杂草科学家估计，每6米棉行中的平均仅两种长芒苋杂草会使棉花产量减少百分之二十三[8]。一棵杂草可以产生450000粒种子。在阿肯色州、田纳西州、新墨西哥州、密西西比州以及最近的亚拉巴马州，农田已经布满杂草。

百草枯被推荐在保护性耕作方案中使用，与其他三种除草剂混合使用。每一种除草剂以不同的作用模式除草。田纳西大学的科学家们已经发现帕默杂草不仅抗草甘膦而且抗磺酰脲类除草剂三氟啶磺酸钠。

草甘膦抗性极易产生

早在耐受除草剂的转基因作物被引入之前，批评人士已经预测，抗草甘膦杂草只需通过抗除草剂作物和其同属的野生杂草之间交叉授粉就繁殖出来了。但他们忽视了“流动基因组”机制，这些机制在应对环境刺激时可改变基因组和基因，並使大多数杂草产生针对除草剂的抗性而不依赖于交叉授粉。在我的书－－《遗传工程：美梦还是噩梦》（1997/1998年第一版）的“伪科学和大企业的冒险新世界”这章节中，我就注意到这些机制 [9]

美国科林斯堡的科罗拉多州立大学的一个由托德·盖恩斯领导的研究小组调查了来自佐治亚州的抗草甘膦藜种群。他们发现，与对草甘膦敏感的植物相比，抗性植物体内负责代谢草甘膦的EPSPS这种酶的编码基因扩增（增殖）了5至160倍 [10]。该基因的表达水平与基因的拷贝数呈正相关。针对该基因的荧光染色表明，被扩增的基因副本存在于每一条染色体。

至少自20世纪80年代以来就已经知道，基因扩增是细胞和生物体对环境中的“选择的”因子最常见的生理反应之一 [9]。

到2009年，有16种杂草被确认有草甘膦抗性[10]。目前已确定的抗性机制包括：草甘膦吸收率降低，和/或EPSPS基因发生突变而使得杂草更难以被除草剂抑制。抗草甘膦藜是首个基于基因扩增而产生抗性的案例。这个例子证明对不受欢迎的因子产生抗性可轻易地进化出来，也证明对大自然发起 “化学战”是徒劳的。

牧草盲蝽：最有害的棉花虫害

在2008年，“牧草盲蝽”侵染了美国480万英亩棉田[11]，成为最具破坏性的棉花害虫。另外一种害虫，棉盲蝽象名列第五，侵害面积达230万英亩。

从加州圣华金河谷流域到弗吉尼亚州东南部的美国的棉花种植带，现在65%的区域都种植了Bt转基因棉花(Table 1 [1])，棉籽象鼻虫和烟草蚜虫自从Bt棉花引种以来已经很罕见了。但是在印度及其他地方[12, 13]，次生害虫特别是牧草盲蝽造成了严重危害。

牧草盲蝽（TPB），学名Lygus lineolaris,从有记录可查的历史以来一直是棉花害虫。在1995年以前，它被针对其他害虫（如烟草蚜虫和棉籽象鼻虫）的杀虫剂控制住。根据密西西比州立大学三角洲研究与推广中心的研究人员的研究[14]，自广泛种植Bt转基因棉花与扑灭棉籽象鼻虫以来，杀虫剂用量减少；结果牧草盲蝽成为棉田的主要虫害。

 “额外的昆虫控制成本源自增加叶面喷洒、较高的技术费和害虫抗性。”三角洲研究与推广中心昆虫研究学者杰夫·戈尔在2010年新奥尔良陆地棉种植会议上介绍说。[15]

在1995年种植一英亩棉花成本为12.75至24美元；在2005年，种植一英亩用“卡迪拉克”处理过种子的抗虫保铃棉、抗农达除草剂棉花的成本是52美元。现在2010年，种植一英亩（孟山都公司的）第二代抗虫保铃棉和抗农达除草剂棉，农民们要花费85美元或更多。

 “在密西西比州，有的棉农要花费超过100美元来控制叶面虫害。你把技术费和种子处理费用加上，就会明白为什么我们的棉花种植面积正在减少。”戈尔说。

更严重的问题是，牧草盲蝽已经对几类杀虫剂产生抗性，尤其是在中南部州的三角洲地区 [14]。

虽然牧草盲蝽是棉花整个生长周期的害虫，但在开花期虫害特别严重，此时害虫大量繁殖，所以其成虫和幼虫都会吸食棉花。大多数虫害吸食发生在棉花的生殖组织。害虫把它们的口器插入小的棉铃。在三角洲的一些地区因缺乏有效控制，由牧草盲蝽造成农作物几乎全部损失并非罕见。

中南部的棉农向戈尔请教种植非转Bt基因的棉花品种，尤其是那些因Bt生物技术花费更高成本的棉农[15]。“我们有一些种植者种了小面积的非转Bt基因的棉花，它们大概从中看到了利润。”

 “但如果我们开始重新种植非转Bt基因棉花，我向你保证，烟草蚜虫就会回来，我们在对付牧草盲蝽之外，不想为了杀死烟草蚜虫而又叶片喷施杀虫剂。在那种情况下，我们被迫的支出的金额将是无法估量的。”

牧草盲蝽在过去四至五年已成为中南部的第1号害虫，正在驱使不再能够负担得起喷剂的费用的许多棉农离开密西西比三角洲流域。

戈尔透露，在南方，叶螨连同蚜虫、椿象一起，也正在获得“预算破坏者”这样的名声。

像牧草盲蝽一样，叶螨对用来控制它们的杀虫剂正在产生抗性。 “过去15年以来，我们已经基本上翻倍了百治磷（Bidrin）的使用率，乙酰甲胺磷的使用率则增至三倍。因此，我们不仅正在喷洒更多的杀虫剂，我们也正以更高的使用率而使成本也提高了很多。”戈尔说。

他指出，为了防治植物虫害而对新烟碱类杀虫剂依赖的副作用是在棉花蚜虫中已经产生了一些抗药性。 “我们开始听到来自中南部许多咨询者的抱怨。”

更多的类似做法是徒劳的

预测令人失望，给农民的唯一的官方学术建议是会首先产生问题的更多的相同的常规做法，即喷洒更多或喷洒不同种类杀虫农药的混合剂，包括已被禁止使用的太毒的杀虫剂。同时，工业已经做好准备以出售含多种转基因性状的品种，可多达八个性状但加倍了种子价格 [16]。

令人失望的是一些国家政府和政府的科学家坚持不懈的努力去促进失败的转基因技术，而我早就讲清楚，那些技术自20世纪80年代初以来已经过时[9]。一份Sciencexpress文件（显示快速出版物，大概没有经过同行评审）题为“粮食安全：喂养90亿人的挑战”[17]其中英国首席科学家约翰·贝丁顿教授为合著者，尽管其中有些轻视目前的转基因作物，但他们仍坚持我们超过30年听到的承诺。 “未来十年，将看到的理想特性组合的发展和新的特性如抗旱性的引入。到本世纪中叶涉及多基因性状的更为激进的方案可能是切实可行的。”它继续承诺“克隆具有对疾病先天免疫进行遗传的动物”等。

草甘膦和“农达”，仍然在把可耐受除草剂的农作物当作“杂草战士”推广的生物技术研究所小册子中被标榜成“对我们的毒性比餐桌上的食盐还低”[18]，实际上正如新的研究结果显示它们非常毒[19，20]（多毒导致死亡，草甘膦和农达，SIS42；现在禁止草甘膦除草剂，SIS43）。 在美国13年的转基因作物种植整体上增加了318百万英磅的杀虫剂用量[21]（在美国转基因作物增加了除草剂农药的使用量，SIS45）。单从这一因素导致的该国额外的疾病负担相当可观。

印度已尝到了来自转基因Bt棉花教训[22]的苦果 ，在恶化的农场自杀事件中，以及同美国一样，在由次生的与新的棉花害虫、抗BT害虫、新疾病带来的生态灾难中，最重要的是，土壤耗尽了营养物质和有益微生物而在10年内将不再支持任何农作物的生长。他们的唯一救星是回归有机农业，因为它已经证明比Bt棉更可持续、利润更高[12]。这可能也会应用于美国。

现在需要耕作实践的一个根本性的转变

在美国，尽管经济衰退，有机产品市场增长势头强劲。据来自美国农业部的最新报告，有机食品的零售销售从1997年的36亿美元上升到2008年度的 211亿美元 [23]（见图1）。该市场是如此活跃，以至于有机农场有时要勉力去生产出足够的供应以满足迅速增长的消费需求，从而导致有机产品的周期性短缺。

 图1 从1997年到2008年美国有机市场的增长态势

经认证的有机耕地面积从1997年时的130万英亩至2005年的400多万英亩（占美国所有农业土地的百分之0.5），已增加了一倍多。在同一时期，有机农场数目从5 021增至8 493，经认证的有机农场的平均规模从268英亩增至477亩。

那么，为什么美国农民没能利用迅速扩大的市场优势？有人认为[23]，潜在的有机农民可能选择继续常规的生产方法，因为“来自附近的对有机农业持有负面看法的其他农民的社会压力”，或因为在过渡期内无法应对天气导致的产量和利润减少的影响。这并不奇怪，由于GM支持者包括政府监管机构对有机农业进行的持续的负面宣传的缘故。（例见由英国食品标准局最近试图证明有机食品的营养不超过常规食品，但它与以下报道相背逆[24]（英国食品标准局的研究证明有机食品更好，SiS44）。通常的声称是，有机农业比常规农业产量较少和需要更多能量，且有机农产品没有更多营养或健康，但与常规生产方式相比却不卫生。在带有已公布科学文献的证据的ISIS报告－－现在看粮食的未来：*有机* 可持续*不使用化石燃料[25]以及其他研究中，这些虚假声称已被彻底驳斥 。

与美国农民最相关的一个研究是由爱荷华州立大学的凯瑟琳·戴拉特和美国农业部的Cynthia A.Cambardella所作的关于从常规农业转变为经认证的有机生产的三年过渡期中的农场绩效评估[26] 。持续四年（三年过渡期的和第一年有机）的实验显示，对大豆和玉米来说，虽然初期产量下降，但在第三年扳平，在第四年有机产量都超出常规农业。

我们的报告[25]也证明（有机耕种）减少温室气体排放量的巨大潜力 - 甚至可使我们完全摆脱对化石燃料依赖的程度——通过有机农业和当地化食品（和可再生能源）系统。这是最新的科学分析与由农民领衔研究的案例的独特结合，尤其是农民自己的经验和创新，往往挫败了拘泥于陈旧和过时理论的学术科学家，其中，转基因技术是一个突出的例子。

大约在我们的报告公布后的同一时间，国际农业知识、科学和技术的发展评估（IAASTD）也出版了。 IAASTD是400名参与科学家和来自全球110个国家的非政府代表三年深思熟虑的成果[27]。它得出的结论是，小规模的有机农业是战胜饥饿、社会不平等和环境灾害的前进途径[28]（“无转基因的有机农业养活世界”，SIS38）。

在农业的崩溃完成之前，现在需要耕作实践中的一个根本性的转变。

原文：

ISIS Report 01/02/10

GM Crops Facing Meltdown in the USA

Major crops genetically modified for just two traits - herbicide tolerance and insect resistance are ravaged by super weeds and secondary pests in the heartland of GMOs as farmers fight a losing battle with more of the same; a fundamental shift to organic farming practices may be the only salvation Dr. Mae-Wan Ho

Please circulate widely, keeping all links unchanged, and submit to your government representatives demanding an end to GM crops and support for non-GM organic agriculture

Two traits account for practically all the genetically modified (GM) crops grown in the world today: herbicide-tolerance (HT) due to glyphosate-insensitive form of the gene coding for the enzyme targeted by the herbicide, 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), derived from soil bacterium Agrobacterium tumefaciens, and insect-resistance due to one or more toxin genes derived from the soil bacterium Bt (Bacillus thuringiensis). Commercial planting began around 1997 in the United States, the heartland of GM crops, and increased rapidly over the years. By now, GM crops have taken over 85-91 percent of the area planted with the three major crops, soybean, corn and cotton in the US [1]] (see Table 1), which occupy nearly 171 million acres.

The ecological time-bomb that came with the GM crops has been ticking away, and is about to explode.

HT crops encouraged the use of herbicides, resulting in herbicide-resistant weeds that demand yet more herbicides. But the increasing use of deadly herbicide and herbicide mixtures has failed to stall the advance of the palmer super weed in HT crops. At the same time, secondary pests such as the tarnished plant bug, against which Bt toxin is powerless, became the single most damaging insect for US cotton.

Monster plants that can’t be killed

It is the Day of the Triffids - not the genetically modified plants themselves as alluded to in John Wyndham’s novel - but “super weeds that can’t be killed” [2], created by the planting of genetically modified HT crops, as seen on ABC TV news.

The scene is set at harvest time in Arkansas October 2009. Grim-faced farmers and scientists speak from fields infested with giant pigweed plants that can withstand as much glyphosate herbicide as you can afford to douse on them. One farmer spent US$0.5 million in three months trying to clear the monster weeds in vain; they stop combine harvesters and break hand tools. Already, an estimated one million acres of soybean and cotton crops in Arkansas have become infested.

The palmer amaranth or palmer pigweed is the most dreaded weed. It can grow 7-8 feet tall, withstand withering heat and prolonged droughts, produce thousands of seeds and has a root system that drains nutrients away from crops. If left unchecked, it would take over a field in a year.

Meanwhile in North Carolina Perquimans County, farmer and extension worker Paul Smith has just found the offending weed in his field [3], and he too, will have to hire a migrant crew to remove the weed by hand.

The resistant weed is expected to move into neighbouring counties. It has already developed resistance to at least three other types of herbicides.

Herbicide-resistance in weeds is nothing new. Ten weed species in North Carolina and 189 weed species nationally have developed resistance to some herbicide.

A new herbicide is unlikely to come out, said Alan York, retired professor of agriculture from North Carolina State University and national weed expert

Glyphosate-resistant weeds from widespread planting of HT crops

Glyphosate is the most widely used herbicide in the US and the world at large. It was patented and sold by Monsanto since the 1970s under the trade name and proprietary formulation, Roundup. Its popularity shot up with the introduction of HT crops. Data from the US Department of Agriculture indicate that the use of glyphosate on major crops went up by more than 15 fold between 1994 and 2005 [4]. The EPA estimated in 2000-2001 that 100 million pounds of glyphosate are used on lawns and farms every year [5], and over the last 13 years, it has been applied to more than a billion acres [6].

It did not take long for glyphosate-resistant weeds to appear, just as weeds resistant to every herbicide used in the past had appeared. The Weed Science Society of America reported nine weed species in the United States with confirmed resistance to glyphosate [6]; among them are strains of common ragweed (Ambrosia artemisiifolia), common waterhemp (Amaranthus rudis), giant ragweed (Ambrosia trifida), hairy fleabane (Conyza bonariensis), horseweed (Conyza canadensis), Italian ryegrass (Lolium multiflorum), johnsongrass (Sorghum halepense), rigid ryegrass (Lolium rigidum), and palmer pigweed (Amaranthus palmeri).

Glyphosate-resistant palmer super weed

Glyphosate-resistant palmer pigweed first turned up in late 2004 in Macon County, Georgia, and has since spread to other parts of Georgia as well as to South Carolina, North Carolina, Arkansas, Tennessee, Kentucky and Missouri [7]. An estimated 100 000 acres in Georgia are severely infested with pigweed and 29 counties have now confirmed pigweed resistance to glyhosate, according to weed specialist Stanley Culpepper at the University of Georgia. In 2007, 10 000 acres of glyphosate-resistant pigweed infested land were abandoned in Macon County.

Monsanto’s technical development manager Rick Cole was reported saying that the problems were “manageable”. He advised farmers to alternate crops and use different makes of herbicides. Monsanto sales representatives are encouraging farmers to mix glyphosate and older herbicides such as 2,4-D, banned in Sweden, Denmark and Norway on account of links to cancer and reproductive and neurological damages. It is a component of Agent Orange used in Vietnam in the 1960s.

Farmers in Georgia are reported to be going back to conventional non-GM crops.

Weed scientists at the University of Georgia estimate that an average of just two palmer amaranth plants in every 6 m length of cotton row can reduce yield by at least 23 percent [8]. A single weed plant can produce 450 000 seeds. Many fields in Arkansas, Tennessee, New Mexico, Mississippi and most recently, Alabama are also infested.

Paraquat is recommended for use in conservation tillage programmes, mixed with up to three other herbicides, each with a different mode of action. Scientists at the University of Tennessee have seen palmer weeds resistant not only to glyphosate but also to the sulfonylurea herbicide trifloxysulfuron-sodium

Glyphosate resistance with the greatest of ease

Critics have been predicting glyphosate-resistant weeds before HT crops were introduced, simply through cross-pollination between HT crops and wild weedy relatives. But they had neglected the ‘fluid genome’ mechanisms that can alter genomes and genes in response to environmental stimuli, enabling most weed plants to become herbicide resistant independently of cross-pollination. I drew attention to these mechanisms in my book Genetic Engineering Dream or Nightmare, the Brave New World of Bad Science and Big Business [9] first published in 1997/1998.

Researchers led by Todd Gaines at Colorado State University, Fort Collins in the United States investigated glyphosate-resistant palmer pigweed populations from Georgia. They found that the gene coding for the enzyme EPSPS responsible for metabolising glyphosate herbicide was amplified (multiplied) 5 to 160-fold in glyphosate-resistant plants compared with glyphosate-susceptible plants [10]. The level of gene expression was positively correlated with gene copy number. Fluorescent staining for the gene showed that the amplified gene copies were present on every chromosome.

Gene amplification is one of the most common physiological responses of cells and organisms to ‘selective’ agents in their environment, known at least since 1980s [9].

Glyphosate resistance has been confirmed in 16 weed species as of 2009 [10]. The mechanisms identified so far include reduced glyphosate uptake, and/or mutations in the EPSPS gene that make it less susceptible to inhibition by the herbicide. Glyphosate-resistant palmer pigweed is the first case of resistance based on gene amplification. It confirms the ease with which resistance to obnoxious agents can evolve [9], and the futility of this ‘chemical warfare’ against nature.

Tarnished plant bug the single most damaging pest for cotton

The tarnished plant bug infested 4.8 million acres of US cotton in 2008 [11] making it the single most damaging pest for cotton. Another insect, the fleahopper ranked 5th, and infested 2.3 million acres.

The Cotton Belt of the United States, extending from the San Joaquin Valley of California to Southeastern Virginia, has largely seen off the boll weevil and tobacco budworm since the introduction of Bt cotton, which now accounts for 65 percent of the area planted with cotton (Table 1 [1]). But, as in India and elsewhere [12, 13], secondary pests are posing serious problems, especially the tarnished plant bug.

The tarnished plant bug (TPB), Lygus lineolaris, has been a cotton pest for as long as records were kept. Before 1995, it was controlled with insecticides targeting other insect pests such as tobacco budworm and boll weevil. According to researchers at the Mississippi State University Delta Research and Extension Center [14], since the widespread adoption of Bt-cotton and eradication of the boll weevil, less insecticide have been used; and as a result, the tarnished plant bug has become the primary insect pest of cotton.

Additional insect control costs are coming from increasing foliar sprays, higher technology fees and pest resistance, said Jeff Gore, research entomologist at the Delta Research and Extension Center, speaking at the 2010 Beltwide Cotton Conferences in New Orleans [15]

In 1995 planting an acre of cotton cost $12.75 to $24; in 2005, planting Bollgard, Roundup Ready cotton with a ‘Cadillac’ seed treatment would have cost about $52 an acre. Now in 2010, with Bollgard II and Roundup Ready Flex, farmers will be spending $85 or more an acre.

“In Mississippi, we have growers who are spending well over $100 for foliar insect control. You add that onto technology fees and seed treatments, you understand why our cotton acreage is decreasing.” Gore said.

To compound the problem, TPB has become resistant to several classes of insecticides, particularly in the Delta regions of the Mid-South states [14].

While TPB is a pest of cotton throughout the growing season, it is particularly damaging during the flowering period, when the pest reproduces copiously, so both adult and immature stages of TPB feed on cotton during the flowering period. Most feeding occurs on reproductive structures. The pests insert their mouthparts into squares and small bolls. It is not uncommon for TPB to cause near-total crop loss in the absence of effective control in some areas of the Delta.

Mid-South growers consulted Gore about planting a non-Bt variety, especially with the higher costs of Bt technology [15]. “We have a few growers planting small acreages of non-Bt cotton, and they’re probably going to see benefits from that.

“But if we start shifting back to non-Bt cotton, I promise you, the tobacco budworm will come back, and we don’t want to be making foliar applications for resistant tobacco budworms, in addition to treating tarnished plant bugs. The amount of money we would have to spend in that situation would be astronomical.”

TPB has been the No. 1 pest in the Mid-South for the past four to five years, and is driving a lot of cotton growers out of the Mississippi Delta, no longer able to afford the cost of sprays.

Gore revealed that spider mites are also gaining a reputation as ‘budget busters’ in the South, along with aphids and stink bugs.

Like TPB, spider mites are becoming resistant to the insecticides used to control them. “Over the past 15 years, we’ve essentially doubled our application rates with Bidrin and tripled our application rates with acephate. So we’re not only spraying more often, we’re applying higher rates that cost more.” Gore said.

He pointed out that a side-effect of relying on neoniccotinoids for plant bug control is some resistance has developed in cotton aphids. “We're starting to hear lots of complaints from consultants across the Mid-South.”

More of the same is futile

It is disappointing though predictable that the only official academic advice given to farmers is more of the same conventional practices that created the problems in the first place, spraying more and spraying mixtures of different kinds of pesticides, including those banned for being too toxic. Industry, meanwhile, is ready to sell varieties with more stacked GM traits; up to eight at double the seed price [16].

Disappointing too is the persistent effort by some governments and government scientists to promote the failed GM technology, which as I made clear, was already obsolete since the early 1980s [9]. A Sciencexpress paper (indicating quick publication, probably without peer review) entitled “Food security: the challenge of feeding 9 billion people” [17] co-authored by UK chief scientist Prof. John Beddington among others, while somewhat dismissive of current GM crops, nevertheless holds out promises we’ve heard for more than 30 years. “The next decade will see the development of combinations of desirable traits and the introduction of new traits such as drought tolerance. By mid-century much more radical options involving highly polygenic traits may be feasible.” It went on to promise “cloned animals with engineered innate immunity to diseases” and more.

Glyphosate and Roundup, still advertised as ‘less toxic to us than table salt’ in a pamphlet from the Biotechnology Institute promoting HT crops as ‘Weed Warrior’ [18], is in fact highly toxic as new findings indicate [19, 20] (Death By Multiple Poisoning, Glyphosate and Roundup, SiS 42; Ban Glyphosate Herbicides Now, SiS 43). Thirteen years of GM crops in the USA has increased overall pesticide use by 318 million pounds [21] (GM Crops Increase Herbicide Use in the United States, SiS 45). The extra disease burden on the nation from that alone is considerable.

India has learned bitter Lessons from Bt Cotton [22] in a saga of worsening farm suicides and, in common with the USA, an ecological disaster in secondary and new cotton pests, resistant pests, new diseases, and above all, soils so depleted in nutrients and beneficial microorganisms that they would cease to support the growth of any crop in a decade. Their only salvation is a return to organic agriculture, which has already proven far more sustainable and profitable than Bt cotton [12]. This may apply also to the USA.

A fundamental shift in farming practices needed now

The organic market has been booming in the United States despite the economic downturn. According to a new report from the US Department of Agriculture, retail sales of organic food went up to $21.1 billion in 2008 from $3.6 billion in 1997 [23] (see Fig. 1). The market is so active that organic farms have struggled at times to produce sufficient supply to keep up with the rapid growth in consumer demand, leading to periodic shortages of organic products.

(Figure 1 Growth in US organic market 1997 to 2008)

Certified organic acres more than doubled from 1.3 million acres in 1997 to a little over 4 million acres in 2005 (0.5 percent of all agricultural land in the US). In the same period, the number of organic farms increased from 5 021 to 8 493, and the average size of certified organic farms went from 268 acres to 477 acres.

So why are US farmers failing to taking advantage of the rapidly expanding market? It is thought [23] that potential organic farmers may opt to continue with conventional production methods because of “social pressures from other farmers nearby who have negative views of organic farming”, or because of an inability to weather the effects of reduced yields and profits during the transition period. This is not surprising on account of the persistent negative propaganda carried out by GM proponents, including government regulatory agencies, against organic agriculture. (See for example the recent attempt by UK Food Standards Agency to prove organic food is no more nutritious than conventional food, which backfired [24] (UK Food Standards Agency Study Proves Organic Food Is Better, SiS 44). The usual claims are that organic agriculture yields less and require more energy than conventional agriculture, and organic produce no more nutritious or healthy, but less hygienic than conventional produce. These false claims are all thoroughly refuted in ISIS report Food Futures Now: *Organic *Sustainable *Fossil Fuel Free [25], with evidence from the published scientific literature, as well as other studies.

Most relevant for US farmers is a study by Kathleen Delate of Iowa State University and Cynthia A. Cambardella of the US Department of Agriculture assessing the performance of farms during the three-year transition it takes to switch from conventional to certified organic production [26]. The experiment lasting four years (three years transition and first year organic) showed that although yields dropped initially, they equalized in the third year, and by the fourth year, the organic yields were ahead of the conventional for both soybean and corn.

Our report [25] also documents the enormous potential for reducing greenhouse emissions – even to the extent of freeing us entirely from fossil fuels – through organic agriculture and localised food (and renewable energy) systems. It is a unique combination of the latest scientific analyses, case studies of farmer-led research, and especially farmers’ own experiences and innovations that often confound academic scientists wedded to outmoded and obsolete theories, of which GM technology is one glaring example.

At about the same time our report was released, the International Assessment of Agricultural Knowledge, Science and Technology for Development (IAASTD) was also published. IAASTD was the result of three-year deliberation by 400 participating scientists and non-government representatives from 110 countries around the world [27]. It came to the conclusion that small scale organic agriculture is the way ahead for coping with hunger, social inequities and environmental disasters [28] (“GM-Free Organic Agriculture to Feed the World[”, SiS 38).

A fundamental shift in farming practice is needed right now, before the agricultural meltdown is complete.

References

1. Adoption ofngenetically engineered crops in the U.S.: Extent of adoption. USDA Economic Research Service, 1 July 2009, http://www.ers.usda.gov/Data/biotechcrops/adoption.htm
2. Super weed can’t be killed, abc news, 6 October 2009, http://abcnews.go.com/Video/playerIndex?id=8767877
3. “N.C. farmers battle herbicide-resistant weeds”. Jeff Hampton, The Virginian-Pilot. 19 July 2009, http://hamptonroads.com/2009/07/nc-farmers-battle-herbicideresistant-weeds
4. Who benefits from gm crops? The rise in pesticide use, executive summary, Friends of the Earth International, Amsterdam, January 2008.
5. 2000-2001 pesticide market estimates: usage, U.S. Environmental Protection Agency, http://www.epa.gov/oppbead1/pestsales/01pestsales/usage2001_3.htm
6. Glyphosate-resistant weeds: can we close the barn door? Weed Science Society of America, 18 November 2009, http://www.wssa.net/WSSA/PressRoom/WSSA_GlyphosateResistance.pdf
7. “’Superweed’ explosion threatns Monsanto heartlands”, Clea Caulcutt, 19 April 2009, http://www.france24.com/en/20090418-superweed-explosion-threatens-monsanto-heartlands-genetically-modified-US-crops
8. “Paraquat fights glypohsate resistant palmer amaranth”, 30 September 2009,
   http://paraquat.com/english/news-and-features/archives/paraquat-fights-glyphosate-resistant-palmer-amaranth
9. Ho MW. Genetic Engineering Dream of Nightmare? The Brave New World of Bad Science and Big Business, Third World Network, Gateway Books, MacMillan, Continuum, Penang, Malaysia, Bath, UK, Dublin, Ireland, New York, USA, 1998, 1999, 2007 (reprint with extended Introduction). http://www.i-sis.org.uk/genet.php
10. Gaines TA, Zhang W, Wan D et al. Gene amplification confers glyphosate resistance in Amaranthus palmeri. PNAS Early Edition 2009, www.pnas.org/cgi/doi/10.1073/pnas.0906649107
11. ARS survey helps growers track two key cotton pests. PHYSORG.com, 1 December 2009, http://www.physorg.com/news178912351.html
12. Ho MW. Farmer suicides and Bt cotton nightmare unfolding in India. Science in Society 45 (in press)
13. Ho MW. Mealy bug plagues Bt cotton in India and Pakistan. Science in Society 45 (in press)
14. Catchot A, Musser F, Gore J, Cook D, Daves D, Lorenz G, Akin S, Studebaker G, Tindall K, Stewart S, Bagwell R, Leonard BR and Jackson R. Midsouth Multtistate Evaluation of Treatment Thresholds for Tarnished Plant Bug. 2009, Mississippi State University Extension Service, http://msucares.com/pubs/publications/images/p2561_pics/bug_1.jpg
15. “Insect control pushes cotton costs higher”, Elton Robinson, Farm Press, 15 January 2010, http://deltafarmpress.com/cotton/cotton-insect-control-0115/
16. Benbrook C. Critical issue report: the seed price premium. The Organic Center. 2009 December. http://www.organic-center.org/reportfiles/Seeds_Final_11-30-09.pdf
17. Godfray HCJ, Beddington JR, Crute IR, Haddad L, Lawrence D, Muir JF, Pretty J, Robinson S, Thomas SM and Toulmin C. Food security: the challenge of feeding 9 billion people. Sciencexpress, 28 January 2010/10.1126/science.1185383
18. Weed Warrior Hebicide-Tolerant Crops, accessed 29 January 2010, http://www.biotechinstitute.org/resources/YWarticles/10.1/10.1.3.pdf
19. Ho MW and Cherry B. Death by multiple poisoning, glyphosate and Roundup. Science in Society 42 , 14, 2009
20. Ho MW. Ban glyphosate herbicides now. Science in Society 43, 34, 2009
21. Cherry B. GM crops increase herbicide use in the United States. Science in Society 45 (in press)
22. Ho MW. Lessons from Bt cotton. ISIS letter to Hilary Benn, UK Secretary of State for the Environment, 4 January 2010, http://www.i-sis.org.uk/lessonsFromBtCotton.php
23. Marketing U.S. organic foods: recent trends from farms to consumers. Carolyn Dimitri and Lydia Oberholtzer, USDA Economic Research Service, September 2009, http://www.ers.usda.gov/Publications/EIB58/
24. Ho MW.UK Food Standards Agency study proves organic food is better. Science in Society 44, 32-33, 2009.
25. Ho MW, Burcher S, Lim LC, et al. Food Futures Now, Organic, Sustainable, Fossil Fuel Free, ISIS and TWN, London, 2008. http://www.i-sis.org.uk/foodFutures.php
26. Delate K and Cambardella CA. Organic production: Agroecosystem performance during transition to certified organic grain production. Agronomy Journal 2004, 96, 1288-98.
27. International Assessment of Agricultural Knowledge, Science and Technology for Development, IAASTD, 2008http://www.agassessment.org/index.cfm?Page=Press_Materials&ItemID=11
28. Ho MW. “GM-free organic agriculture to feed the world”. Science in Society 38, 14-15, 2008.

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