b'POPEYE WAS RIGHTPART 2FROM PESKY PESTS TO NBTS: A CLOSE LOOK AT SPINACH BREEDING.BY: MARCEL BRUINSI n Part 1 of our spinach breeding story we looked at what itDOWNY MILDEWmost serious of all spinach diseases. takes to develop a new spinach variety, how much time andThis pathogen is the money it takes, and how breeders make sure their breedingBreeding for resistance to it is therefore a substantial focus for programs are aligned with what consumers want. In this Part 2,all firms, but this is made extremely difficult because new races we look at the organic market, and the slew of nasty spinach dis- of the pathogen continue to emerge regularly. eases that the breeders need to find an answer for. We also askedThe chances this battle will end soon are low, says them their thoughts on the use of new breeding techniques andJaarsma, with Laan having a similar view. There will never be whether they felt they had enough access to germplasm for theiran end to the constant battle to achieve DM resistance, he says, breeding efforts.for as long we are working with vertical resistance (key and lock). Up till now the pathogen has always been able to crack ORGANIC MARKET the codes.Because spinach already has high amounts of vitamins and min- Dew Kumari Sharma, spinach breeder at Vilmorin-Mikado, erals, increasing those levels is not a focus for breeders of thisexplains further about the nature of the battlethat the new crop, but organic variety development is key. The organic babyraces of DM that continuously surface break down the resistance spinach sector is important in the U.S. market in particular, saysgenes deployed in newly-released varieties. Today, we have 19 Rinse Jaarsma, breeder spinach at Syngenta. races, of which more than 10 races were identified in the last Raimon Laan, spinach breeder at Bejo Zaden, explainsthree decades while the first one dates back to 1824, she says. that in general, the organic spinach sector is catered to withWhy is this evolution going so rapidly in the past few decades NCT seed (seed that undergoes National Cooperative Testingcompared to the distant past? Well, there are many reasons, for for accreditation by the National Seed Industry Council). Hisexample, intense year-round high-density planting and limited company offers several varieties that are produced organicallycrop rotation. But another important reason I would like to high-as well. The majority of spinach breeding investment at KWSlight is that if we rely only on the limited number of full-package Vegetables is focused on the development of disease-resistantresistant varieties that are available in the market, the genetic varieties for the organic market. base operating at the field-level is narrow. That increases nat-The organic spinach market in Europe would grow quiteural selection pressure on the pathogens, leading to the emer-a bit faster, according to Ole Johansen, managing director atgence of a new race more frequently.DeSeed, with regulatory change. Right now, EU regulationsKumari Sharma stresses that for breeders to reach the require organically produced seed, representing an impedi- finish line of the DM resistance race, they will have to use the ment to expanding the organic spinach sector. Spinach seednaturally available genetic resources more sustainably, and opt can carry seed-borne pathogens situated below the seed coatfor more durable horizontal resistance by incorporating quan-and the seed yield of organic seed is low, he says. Hence thetitative genes in addition to the few major genes to broaden the cost of seed may be two to three times higher than conventionalgenetic base on the commercially available materials. Johansen untreated seed.agrees that the dream is to identify horizontal resistance.26IEUROPEAN SEEDIEUROPEAN-SEED.COM'