Handpollinerade grödor

[Lars i skogen]

 Jag tror att de allra flesta är medvetna om att all uppmärksamhet som "bidöden" fått de senaste åren är kraftigt överdriven, åtminstone vad gäller honungsbin. (vildbin är en annan historia). I samband med diskussion om bidöden hör jag gång på gång från olika håll historien om "en region i Kina där alla bina dött och därför måste pollineras för hand". Eftersom jag är född kritisk så tror jag att det bara är en modern myt,  en lögn helt enkelt som villigt sprids av alla som vill propagera för biodling.

Men jag kan ju såklart ha fel. Finns det någon här som kan presentera en TILLFÖRLITLIG källa på att historien om Kina är sann?

[Edward.]

duger Newsweek?

http://www.thedailybeast.com/newsweek/2008/06/14/stung-by-bees.html
Stung By Bees
Jun 14, 2008 7:52 AM EDT


A mysterious ailment of honeybees threatens a trillion-dollar industry and an essential source of nutrition.

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For 3,000 years, farmers in China's Sichuan province pollinated their fruit trees the old-fashioned way: they let the bees do it. Flowers produce nectar that attracts bees, which inadvertently transfer sticky grains of pollen from one flower to another, fertilizing them so they bear fruit. When China rapidly expanded its pear orchards in the 1980s, it stepped up its use of pesticides, and this age-old system of pollination began to unravel. Today, during the spring, the snow-white pear blossoms blanket the hills, but there are no bees to carry the pollen. Instead, thousands of villagers climb through the trees, hand-pollinating them by dipping "pollination sticks"—brushes made of chicken feathers and cigarette filters—into plastic bottles of pollen and then touching them to each of the billions of blossoms.

China's use of human bees is only one of many troubling signs of an agricultural crisis in the making. Bees the world over have been dying from a mysterious syndrome termed colony collapse disorder, or CCD. U.S. beekeepers lost 35 percent of their hives this winter, after losing 30 percent the previous year. Similar but less well-publicized losses have occurred in countries as far-flung as Canada, Brazil, India and China, as well as throughout Europe. A recent survey of wild-bee populations in Belgium and France found that 25 percent of species have declined in the past 30 years. Several species of bumblebees common in the United States as recently as 1990 have disappeared. In Britain, the British Beekeepers Association has warned that honeybees could disappear entirely from the island by 2018, along with £165 million worth of apples, pears, canola and other crops they pollinate.

The threat is vast. Most crops—87 of the world's 115 most important ones—require pollination to develop fruits, nuts and seeds, says agroecologist Alexandra-Maria Klein at Germany's University of Göttingen. Those crops account for about $1 trillion of the approximately $3 trillion in annual sales of agricultural produce worldwide. They also provide 35 percent of the calories consumed by humans each year, and most of the vitamins, minerals and antioxidants. Every blueberry, cherry, apple, grapefruit, avocado, squash, cucumber, macadamia nut and almond depends on the ministrations of a bee for its existence. Even crops such as lettuce and broccoli need insect pollination to produce seed for the following year's supply.

Colony-collapse disorder is characterized by the sudden collapse of a full-strength hive in a matter of weeks, with adults leaving the hive and not returning, until the hive is deserted. "I found colonies that had just stopped living," says Borje Svensson, a Swedish beekeeper. "They had given up life without any sign of struggle." No one knows what causes it, but theories abound. U.S. researchers believe a previously little-known disease called Israeli acute paralysis virus is involved, while Spanish researchers suspect a fungus called Nosema. When France lost a third of its bees in the 1990s, beekeepers blamed Imidacloprid, a new pesticide that had been used on the sunflower crop, a honeybee favorite. France banned the use of Imidacloprid on sunflowers in 1999 and expanded the ban to other crops in 2004, yet its bees have not recovered. Despite this ambiguous evidence, many beekeepers around the world continue to blame Imidacloprid—the best-selling pesticide in the world, with annual sales of nearly $860 million. Others have pointed fingers at malefactors ranging from cell phones to genetically modified crops, with little evidence. The leading theory is that colony collapse is caused by a combination of viruses, pesticides, the parasitic varroa mite, drought and stress triggered by commercial colonies' overwork and poor nutrition.

The meta-culprit is the shift to large-scale agriculture. When most farms were small family affairs, pollinators came from nearby wildlands. But the growth of massive industrial farms has put most crops out of the reach of wild insects. So farmers need to supply artificially large numbers of bees to pollinate their fields in the spring. The European honeybee is the only pollinator that fits the bill: adapted for dense living in tree hollows, it takes naturally to man-made wooden hives, making it the only bee that comes in convenient boxes of 50,000 that can be trucked from crop to crop. Wild insects such as bumblebees and tropical flies still account for 15 percent of pollination, including crops such as cacao (chocolate). Yet these wild insects are declining worldwide due to loss of habitat and increased pesticide use. Farmers the world over now rely almost completely on the European honeybee, one of 20,000 species of bees. Many beekeepers now make more money from pollination fees than from honey production.

[Lars i skogen]

Tack! Fast jag vet faktiskt inte om det duger... 
Att päron handpollineras tror jag på, men kopplingen till bidöd är oklar. Enligt artikeln verkar handpollineringen bero på att man använder väldigt mycket gifter i dessa odlingar. Vilket kanske är omöjligt tillsammans med biodling i och för sig, men det är ju isf inte döda bin som gjort att man tvingats handpollinera, utan att man valt att bespruta och istället låta människor sköta pollineringen. Idioti är det ju såklart även i mina ögon, men har väl inget med CCD (eller annan bidöd) att göra?

[Rune H]

Som jag uppfattat det har men valt att bespruta. Bina  - och andra pollinerande insekter har dött - och man tvingas handpollinera. Jag tror inte att man valt att utrota insekterna för att man skall handpollinera utan att men tvingas till det därför att man använder kemikalier.

Jag tror att du kan hitta en hel del uppgifter hos Coloss http://www.coloss.org/.
Det har rapporterats ovanligt stora förluster från flera länder. Orsakerna tycks vara olika. Allt ifrån användningen av kemikalier ( lokalt i Kina - se ovan) till CCD (USA).  Ibland är det fråga om ett nytt "hot" som varken bina eller biodlaren lärt sig hantera ännu ( t.ex- den asiatiska getingen i Frankrike), en svår vinter ( England för några år sedan) osv.
Det finns således ingen entydig gemensam förklaring till varför bina dör.
Tyvärr tycks det inte finnas någon täckande statistik för jordklotet, När det gäller t.ex. många länder i Afrika är det svårt att få klara uppgifter.

[Lars i skogen]

Tack! Där kan jag lägga många timmar på att läsa själv!

[Rune H]

Det skulle vara roligt att veta om du fortfarande tror att bidöden är en myt efter att ha studerat lite av det material som COLOSS tagit fram.
Personligen tror jag att de persosner/institutioner som ingår i COLOSS har en hög trovärdhet.