BREEDING OF MAIZE

Gisborne Herald, Volume LXXIV, Issue 22510, 13 December 1947, Page 8

BREEDING OF MAIZE

NOTHING HAPHAZARD J SELECTION OF TYPES ’ The breeding of hybrid maize was \ dealt with fully by the fields instructor I to the Department of Agriculture, Mr { H. deO. Chamberlain, in a lecture on f Thursday evening to members of the ; Manutuke Young Farmers’ Club. ■ Hybrids were made by crossing lines of either the same variety or of different varieties. This was not done ? haphazardly, but with careful thought \ about the object desired. For example. ‘ a breeder might have two sorts of 1 maize, one which reached maturity at ; a suitable time for his district, but did 1 not yield well, and one that yielded well, but matured too late. The object there was to combine the two desirable characteristics and produce a heavy yielding maize which ripened before frost injured it. All individuals, said Mr Chambers in. embodied within themselves a large series of characteristics—some good and some bad —which were not always apparent to the eye. Before hybridising, these characteristics must be broken down so that the undesirables could be discarded. This was done by self-pollinating the two par-ents-to-be in circumstances of isolation until it was considered that the progeny remaining at last bred true, and worthless attributes had been discarded. 4 Long Initial Process That process might take years of even longer, but until it was complete, hybridising could not commence. Mr Chamberlain, then, by means of diagrams, showed the method used to hybridise the in-bred lines. Explaining that vigour and yield were highest in the double hybrid so produced, the lecturer demonstrated that this acouired vigour and yield declined the further away seed was used from the parent hybrid. Thus seed once removed from the double-yield could be expected to have about 20 per cent less vigour and yield less, accordingly. Also, later generations tended to produce mixed types. To avoid that and. to ensure a plentiful supply of double hybrid seed, the Deop'-tment of Agriculture had sown out 25 acres of parent stock this year, which would be available to growers m the coming season. It was intended that areas of parent stock should be grown each year for that purposes. These areas were grown under contract to the department under conditions of complete isolation and under direct expert supervision. In addition to the benefit to farmers, accruing from a certified source of local supply, that arrangement ensured that any loss of yield, which might pertain during the stage of acclimatisation of imported seed, would not be borne by the growers, but by the Department of Agriculture. , , A vote of thanks was accorded Mr Chamberlain for his instructive address.