MAIZE BREEDING. 6l 



short shank. The leaves should be strong and broad to enable 

 these to manufacture sufficient food to fully mature the grain. 

 The cobs should be broad with the grain close set in straight rows 

 which run out well top and bottom. The sheaths must cover the 

 tops of the ears and the grain should be wedge-shaped so as to pack 

 closely on the cob. Length of grain is an advantage, as it gives a 

 greater percentage of grain to cob. When the crop has become 

 ripe the best ears are selected from these selected plants, and are 

 carefully stored. The following season each of these ears is sown 

 separately, making one row from each cob. The tips and bottom 

 should be removed, as the grain is probably not quite as large at 

 the extremities as in the middle of the cob. From actual ex- 

 periments carried out in America it is found that if anything the 

 grain at the tip will produce quite as much grain in the subsequent 

 crop as the seed from the centre of the cob. 



In-breeding with maize, as with any other monoecious plants, 

 should be avoided as far as possible, as this reduces vitality and 

 productiveness. Therefore, when the rows of mealies in the breed- 

 ing plot have reached the flowering stage it is as well to remove the 

 tassels from every other row and only to select seed from the 

 detasselled row for the following season. This plan makes it ab- 

 solutely certain that the plants from which the seed cobs have 

 been removed have not been fertilised with pollen from their own 

 tassels, and so inter-breeding but not in-breeding is maintained. 

 Another method is to detassel the odd numbers of half the rows 

 throughout the field and the even numbers for the remaining half. 

 This method, is, however, not as certain as the one already described, 

 as with a high wind the pollen from plants grown from seed from 

 the same cob may yet be carried to detasselled plants also raised from 

 seed from the same cob. On the other hand, it gives a fair chance 

 to all the rows, as the row detasselled may turn out poorer than 

 the one which has not been detasselled, as it is impossible at the 

 time of tasselling to tell which cob row is likely to turn out best. 



Cross-Breeding. 

 Cross-breeding should only be taken up by those who fully 

 understand it, and have first determined on what lines they intend 

 to proceed, otherwise the result is likely to be disastrous. Before 

 dealing with this question I may state that in America it seems to 

 -be felt that there is quite as much to be said for broad breeding as 

 there is for narrow breeding, as far as the maize crop is concerned. 

 Mendel's Laws are being applied to the breeding of grain to a great 

 extent, and this being the case, it is necessary to find out which are 

 the dominant and which are the recessive characters. The law of 

 dominance may be applied provided that the parents which are 

 used for crossing are pure-bred. If the parents are not pure-bred 

 the characters will not occur in the definite proportions which they 

 should do, namely one of the recessive to every three dominant. 

 Thus if for crossing purposes we were to take the 75% of dominant 

 seeds and were to cross these with another strain our calculations 

 would be entirely upset. If, however, we took the 25% of grain 

 showing the recessive character and crossed this with another pure 



