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Traditional breeding: major accomplishments

Traditional breeding: major accomplishments. Bert Visser Copenhagen, 13 december 2005. Scope of this presentation. actors the succession of breeders results food security yields resistances hybrids starting materials germplasm collections. Actors: the succession of breeders.

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Traditional breeding: major accomplishments

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  1. Traditional breeding:major accomplishments Bert Visser Copenhagen, 13 december 2005

  2. Scope of this presentation • actors • the succession of breeders • results • food security • yields • resistances • hybrids • starting materials • germplasm collections

  3. Actors: the succession of breeders • domestication started only 10,000 years ago • until 19th century all breeders were farmers • (not all farmers were breeders) • small breeding enterprise emerged in 19th century • breeders became specialists • breeders used genetics • breeding was core business • large mergers accelerated in the rise of biotech • breeding a multidisciplinary affair in multinationals • increasingly, varieties vehicle to sell traits

  4. Results: food security • current human population levels depend on plant domestication • Green Revolution (1970s/1980s) • cereal production expanded faster than world population • prevented large-scale famines in e.g. India and China • in 2002 world food supply 20% higher than in 1961 • real prices 40% lower • (Borlaug & Dowswell, 2003)

  5. Food security versus food sovereignty • food security • food may be available, but: • does it reach every person? • is it affordable to all persons? • food sovereignty • deals with autonomy • the right to choose • challenges globalization and food product uniformity

  6. Results: yield as a complex • yield is the result of several factors • germplasm • irrigation • fertilizer • pesticides • mechanization

  7. Results: some yield figures (1) • actual yield increases between 1960 and 2000 • wheat 208% • rice 109% • maize 157% • potato 78% • cassava 36% • high-yielding semi-dwarf varieties • on 84% of wheat area • on 74% of rice area • harvest index increased from 0.3 to 0.5 (Kush, 2003)

  8. Results: some yield figures (2) • yield potential (Kush, 2003) • from 4 to 10 tonnes/ha for rice and wheat • annual growth of wheat potential • grain production per capita (Kush, 2003) • in 1984 342 kg, in 1996 321 kg • cropping period from 150 – 180 days to 110 days • drought avoidance • three croppings per year

  9. Results: new resistances • resistances introgressed from wild relatives • many not available from farmers’ varieties • based on wide crosses • wheat, rice, maize, tomato, lettuce, etc. • some diseases erased (De Nijs, pers. comm.) • cucumber scab • cucumber leaf spot • some pathogens contained • potato nematode species (Globodera rostochiensis)

  10. Resistances from genebank stocks • resistance against tomato spotted wilt virus (De Ponti) • rust resistance in wheat (CIMMYT) • Hessian fly resistance in wheat • stripe rust in barley • polygenic scab and mildew resistance in apple (BAZ) • grassy stunt resistance in rice (IRRI) • Fusarium wilt in pigeon pea (ICRISAT) • late blight in potato (USDA-ARS) • late blight in potato (CGN)

  11. Hybrid development • two major motives • agronomic: hybrid vigour • economic: biological property protection • higher yields in hybrids • rice yields up to 10 tonnes/ha (China) • attractive trait combinations from different parents • what if similar investments had been spent on open pollinating varieties?

  12. The role of germplasm collections • ex situ collections sources of resistances • major use motive for breeders (CGN questionnaire) • wild relatives major component of collections • utilization in subsequent steps, contributions by several actors • ex situ collections potential sources of many traits • quantitative traits • non-expressed traits • paradigm shift (Tanksley and McCouch, 1997)

  13. Conclusions (1) • in developed countries food production taken for granted • not high on politician’s agenda • in developing countries remaining issue • shift towards sustainability aspects • in developing countries Green Revolution major impact on food production • more on yield than on sustainability • exclusive focus on staple crops

  14. Conclusions (2) • immense diversity available through traditional breeding • not exhausted • GM crops largely technology push and economically inspired (patentable traits and processes) • GM technology any impact on food security? • currently only four crops, two traits, six countries • only developed for markets with purchasing power • only marketed if patents can be enforced

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