by Dr. Sydney Ellerton
Sugar beet breeding occupied a large part of my life and indirectly influenced Lilian and John through all my working years, so I must attempt to outline what it was all about. As in many fields of science, there was more innovation and change during the years following World War II than there had been during the previous century.
Beet breeding had existed as simple selection from the time the crop was first brought into being in the late 18th century. In those days, however, it hadn’t much of a chance, for cane sugar could be very cheaply imported from a whole lot of places. However, it began to blossom in France under Napoleon. In fact, sugar beet seemed to prosper on naval blockades. Just as the German submarine blockade during the first world war had led to the establishment of a beet industry in Britain, so at the beginning of the 19th century it was the British navy who were the villains of the piece. They blockaded the French West Indies and Napoleon reacted by subsidising a domestic beet industry.
A sugar beet variety was a population, a mass of individuals each different from the others as is the case in humans. So early breeders had the task of picking out superior plants from the mass and growing them on for seed. Sounds easy but there were snags. Just picking out big roots to grow on would largely mean picking out lucky roots which had had a bit more space to grow in, a bit richer soil or some other good fortune. However, this problem was solved to a large extent by a certain Louis de Vilmorin in the 19th century. He invented the progeny test which was subsequently applied to just about every form of plant or animal breeding. The idea was that you picked out what appeared to be good plants but then grew them on to seed separately, in the next year comparing not single plants but whole progenies one against another.
There were still big problems. It wasn’t enough to pick out families of big roots, for they might well be poor in sugar content and at first there was no easy way of checking that. Soon, however, came a device called a polarimeter, the same device being called a saccharimeter where the scale was graduated in sugar percentages. Juice was extracted from the beets to be tested, clarified and poured into a long tube. Polarised light, in which all the vibrations were in one plane, was shone down the length of the tube and the plane was caused to rotate: more sugar, more rotation. There was an eyepiece at the end of the tube and some unfortunate (now and again it was Lilian) would spend hours in a little dark room, peering into the gadget and twiddling a knob until the brightness of the two halves of the field of view matched. Then the sugar content could be read off on a scale.
Even picking out superior progenies wasn’t easy. You had a field full of plots but it was never uniform and special statistical techniques had to be invented to distinguish between real and chance differences. The English statistician R.A. Fisher was the great pioneer in this field, publishing in the mid-1920s.
This was the situation in the early days in Maldon. The rented farmhouse at Beeleigh, two miles from Maldon, was fully utilised. Upstairs, Kenneth Hedge and his family were installed. One of the two front rooms downstairs had many hundreds of single plant seed progenies in manila packets hanging on wires from the ceiling, the other front room being an office. The former farm kitchen was the laboratory and the pantry housed the saccharimeter. The single storey extension at the back housed a large tank of cold, muddy water in which roots were washed and scrubbed by hand and a boring machine with a Keil rasp to take samples for analysis. The drive to this was old style: there was an electric motor suspended from the ceiling with a flat belt drive down to fast and loose pulleys on the machine.
This remained the situation until 1945, when we moved into Woodham Mortimer. There a basically similar system albeit with some refinement was set up in the downstairs rooms and it was the Ellerton family who lived upstairs.
Before long things began to move more quickly by the drawing together of a number of originally quite unrelated strands, though the changes occupied ten years or so. Horticulturists had long since known that a strain of certain ornamental plants could turn up with especially big flowers. They called them gigas types. It appeared that these had more chromosomes than usual in every cell, four sets instead of two. They were called tetraploids. Wouldn’t it be marvellous if we could produce such types to order, and have bigger and better crops? There were various strange and unreliable ways in which this might be done, but not long before the war, two Americans, Blakeslee and Avery, had discovered a good way to do it. It involved the use of a substance called colchicine, obtained from the autumn crocus and known as a treatment for gout. When I was in America in 1937-38, polyploidy (the collective term for all plants with an increased number of sets of chromosomes) was the bandwagon of the day and most breeders I met were trying out colchicine on all kinds of plants.
In Europe, sugar beet breeders had been playing this game too, in Germany and in Scandinavia. Early hopes of instant magic were soon dashed. Tetraploid sugar beet did not prove to be an instant way to bigger crops, in fact they were rather lower than normal in sugar content and in yield. Hope soon grew that if these tetraploids were crossed with ordinary beets the hybrids (triploids, with three sets of chromosomes) would show hybrid vigour and be superior. Evidence that this was so was soon gathered, but there was no way that such triploids could be produced in quantity. All that could be done was to grow seed plants of tetraploids and diploids together as a mixture and let them interpollinate at random. The harvested seed had three components, the normal diploid, the hopefully superior triploid and the inferior tetraploid and these mixtures, called ‘polyploid’ varieties were put on the market and hailed as a great advance.
There was consternation among breeders who had not been working along these lines, especially when Oswald Rose, of the British Sugar Corporation, came along to tell us that we would all be stone dead if we did not get into this immediately. In Britain there were a number of seed firms which had joined together in the British Sugar Beet Seed Producers’ Association. They had by no means all been doing their own breeding, some being dependent on overseas breeding firms which had not been into polyploids either. It was rather funny in some ways. Of the gathering of maybe fifteen people, only two, Kjell Lindqvist (a Swede) and I had the faintest idea what a polyploid was. What came out of this meeting was a proposal that there should be a single breeding organisation for the Association, with me in charge. Flattering, but impractical, because it was soon made clear that the single firm which at the time had nearly half of the entire U.K. sales would not come in. This was Sharpes’ of Sleaford, who received their basic seed from Germany, from the Kleinwanzleben company which already had polyploids on the market.
The scheme fell apart after that, but when it had done so, Johnsons of Boston, Lincolnshire picked up the baton and asked us to supply their stock seed. They had previously been associated with a Dutch firm, Kuhn, which had a proud history in sugar beet breeding, but which had fallen from grace.
Polyploidy looked like being a modest success and we found ourselves making thousands of microscopic preparations and counting chromosomes ad nauseum, sometimes even in our dreams.
The difficulties had by no means all been solved. Sugar beet varieties were still mixed populations and everybody knows from human analogy that if the genetic base gets narrower and narrower (as it would in a small isolated community or from repeated selection) problems arise from inbreeding, especially a lack of vigour and consequent yield. Further selection would do no more than reach a balance between improvement and deterioration.
Now the United States comes into the picture again, right back to an idea put forward by geneticists East and Shull in 1910. They advised close inbreeding, in fact self-fertilisation (most plants are both male and female so this is possible) and said not to worry about the terrible poor vigour of the inbreds. They said that if you then crossed unrelated inbreds one with another a massive amount of hybrid vigour would be restored and the resulting varieties would be the best ever. The cross between two inbreds had the further advantage that it would be genetically uniform. This idea led to very great advances in maize breeding from the 1930s. But maize was such a wonderfully handy plant, with the male and female flowers totally separated so that crossing inbreds was dead easy. For many years it was a mostly remunerative holiday task for thousands of American school-children. Sugar beet, with many hundreds of tiny florets per seed plant and male and female parts in each flower, was not a bit like maize and about as awkward as anything could be.
Now the story goes back to Salt Lake City and to F.V. Owen’s efforts to make sugar beet behave like maize. I had seen him trying to do this back in 1938, with very close temperature control to sterilise the male parts of the flowers. This was terribly difficult with single plants and quite impractical on a large scale. Later Owen hit on a form of beet which produced no pollen, without any special treatment at all, so it all looked easy.
It wasn’t, though. How could you breed it, if there were only females? Here we had a sugar beet plant which produced no pollen and the only way to reproduce it was to cross it with a normal pollenbearing plant. It soon appeared when this was done the progeny of the so-called male-sterile plants were fertile and this great new discovery seemed to be lost. However, Owen persisted, crossing his male-sterile type with many different pollinators. He finally located some pollinators which did not carry the genes which restored fertility. These he called O-types and by using them it became possible to develop male-sterile inbreds, a sugar beet breeder’s dream.
It was years before the system was quite stabilised, but eventually sugar beet could in principle be bred just like the maize which had yielded such successful hybrids. The new trick of male-sterile and non-restorer (O-type) breeding was now applied to maize and the army of students and schoolchildren formerly employed in crossing corn were no longer needed. After years of work in getting sugar beet to breed like maize, at last we had arrived!
At this point, politics came into the picture again and this time to our advantage. In the post-war years the Americans had come up with the Marshall Plan, aimed at setting Europe on its feet again after all the devastation. This help took many forms, and one of them was to supply European beet breeders with this valuable new male-sterile sugar beet, without charge or restriction.
This was just what I had been waiting for. Now the possibility existed of producing sugar beet varieties which were purely triploid. It was going to be expensive, though, for the male-steriles were very far from perfect, both in sterility and in adaptation to European growth conditions, and there was much work to be done. The other side of the coin was the production of the tetraploids, also an expensive business and the triploid hybrids needed most extensive field testing. Seed on the market at the time was all old-style, at old-style prices. The farmer paid about 10½d (4½p) per pound. No way could the new style breeding be financed by such sales, so we looked for help. This came from a Dutch company, D.J. van der Have, with exactly similar problems and we organised a joint breeding scheme. In the years which followed the Dutch breeder Ton Hendriksen and I met for a day each month, in England or in Holland, and made some very good friends in the process. The result was the production of the first triploid sugar beet in the world, which we named Triplex.
All these hybrids exacerbated an already big problem, handling enormous masses of numerical data. If you had 100 female inbreds and 100 male you already had 10,000 possible hybrids to test. A very special sampling technique had to be worked out, for it was impossible to put them all in field trials especially at a whole lot of different locations. The mass of data was further increased because the sugar companies were now demanding high quality beet which caused minimum manufacturing losses. They wanted low amino-nitrogen content and low sodium and potassium. In came the cuprammonia test and the flame photometer. It was all overwhelming, or it would have been if computers had not turned up just in time. We managed to invent a number of new statistical techniques and we could then cope. Praise be unto the computer! How chance circumstances interact. Lilian’s brother Wyn, when he returned from his long war, had not gone back to banking but got into computers at a very early date. His job was to reorganise the office systems of a succession of major companies to use the new wonder technique. We talked about it and I saw the possibilities for my work. The result was that I was using computers back in 1968 and was fully prepared for the new flood of data handling.
Now came something else. Sugar beet had just about the most awkward seed ever, a knobbly, corky, irregularly shaped thing. It wasn’t really a seed at all, but a fruit which contained several seeds. This led to a major problem. When sown in rows, many surplus seedlings came up and they were not nicely, evenly spread but came in little, tight groups. The several seeds in a single ‘cluster’ would germinate on almost exactly the same spot. The only answer was to go after them with hand hoes and even to get down on hands and knees to do the job of thinning to just one young plant every nine inches or so. This was very costly for the farmer, but for many years the Americans could bring in cheap labour from Mexico and we had the gypsies and Irish seasonal workers. The cost was going up all the time, though, and the American labour unions felt that cheap seasonal immigrants offered unfair competition and managed to get legislation through, prohibiting their entry. So something had to be done, and done fast.
The first approach was mechanical, invented by Prof. Roy Bainer of the University of California at Davis. We used it briefly in our seed warehouse. The ‘seed’ was broken up (segmented) mechanically and then screened to a nearly uniform size. The plants did not like this rough treatment a bit and grew rather weakly. The next approach was to achieve the same object more gently. The seed was passed between rotating rubber pads, and graded for size as before. This was better, and precision drills, which sowed the seed at uniform intervals, were being developed and improved. It was still not perfect, though, because many of the pieces still contained more than one seed and others no viable seed at all. At this point breeding came into the picture from an unlikely source, Soviet Russia. In the Ukraine, some strange seed plants had been noticed, not by chance but after a very extensive search. These plants had tiny green flowers occurring singly on the stems instead of in the usual little groups. Now it was possible to think of breeding the ideal seed for precisely spaced sowing. The war, not surprisingly, had created enormous disruption in the Soviet Union. The head of the All-Union Plant Breeding Institute in Kiev, and his wife had become personae non grata with the Russians prudently managed to get out to Germany. From there they were sought out by the Americans, who had heard of the new, monogerm seed plants in Russia and wanted them very urgently. Viacheslav and Elena (Helen) Savitsky moved to America and soon claimed to have rediscovered the monogerm type of seed plant in seed crops in Oregon. The claim was that they succeeded because they knew what they were looking for and could spot the odd plant among millions of the purely ordinary. This is very likely, but the suspicion that they might have sneaked a few of the Russian seeds over with them will, however, probably never quite be dispelled.
Again, the U.S. government was remarkably generous and, at a very early stage, supplied European breeders with some of the new seeds. They had all sorts of faults, but improvement work went on apace and in due course our company produced the first monogerm variety to go on to the British market. It also was triploid, for we could use the same tetraploid pollinators as we had used for Triplex, the monogerm character being entirely a maternal characteristic. There was still lots of room for improvement and this will presumably go on ad infinitum, but such seed, raised on male-sterile mother plants, is the basis of all present-day sugar beet varieties.
During these years we got involved with America too. In Europe there was the I.I.R.B., an association for research workers in sugar beet; not only breeders, of course. I had become a member in 1947. There was a similar society in America, the A.S.S.B.T. (American Society of Sugar Beet Technologists) and I became a member of that too and went over there in 1954. This led eventually to a second overseas collaboration, now three-way, for it involved our Dutch friends too. It was with what at the time was the premier beet sugar company in America, the Great Western Sugar Company of Denver, Colorado.
From this point onwards, life, both family and technical, took on an international aspect. This proved to be a great source of pleasure. It led to a continuously updated world view of developments in scientific matters appertaining to sugar beet, and it also led to many close and durable family friendships. The year in the International House community in Berkeley before the war had prepared me for all this, and in particular, I felt completely at home in America.