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IMPORTANCE OF SELECTION OF SEED. 



Ripe Seeds. 



Prof. J . C. Arthur, Botanist of the Indiana Station in the United 

 States has been experimenting since 1889 on the use of unripe tomato 

 seed, Mnd how far this is an advantage in causing the plants to produce 

 their fruits earlier, and in making them more productive. Compari- 

 sons were made with plants grown under the same conditions from quite 

 ripe seed taken from the same parent. The author arrives at the fol- 

 lowing conclusions : — The principal deviations arising from the use of 

 immature seed are : ( 1 ) A loss of vigour, shown in the smaller percen- 

 tage of germination, weakness of the seedlings, and greater number of 

 plants that die before maturity ; (2) failure to recover lost vigour, al- 

 though the plants may, and usually do, produce an abundant harvest, 

 and one acceptable to the cultivator ; (3) The increase of reproduc- 

 tive parts in proportion to the vegetative parts, resulting in a greater 

 number of fruits and (seeds although individually smaller) and more 

 rapid ripening than in similar plants from mature seeds. 



In Jamaica there is no winter season to interrupt cultivation, and 

 there is no difficulty in sowing seed so as to produce a crop at any season, 

 if a proper amount of water is supplied. We need not therefore force 

 nature to shorten the time of maturing, at the expense of a total larger 

 crop, and larger fruit. The seed should be quite ripe. 



Large Seeds. 



The same author investigated the reciprocal relation between the 

 vegetative (leaf stem, and root) and the reproductive (seed and fruit) 

 part of plants under varying conditions of growth. The generalisation 

 is reached that : 



A decrease in nutrition of an organism favours the development 

 of the reproductive parts at the expense of the vegetative parts. The 

 decrease in nutrition may be brought about by poor soil, bad tillage, 

 slow germination, etc., all leading to the same general result. But it was 

 pointed out that while partly starved plants are as a rule proportionately 

 more productive, i. e., per unit of vegetative part, the reverse is true of 

 plants grown from large and small seeds, for ' large seeds produce 

 stronger plants with a greater capacity for reproduction than small 

 seeds of the same kind/ These conclusions, which are supported by 

 experimental data, strongly emphasize the necessity of using only the 

 largest seeds (that is, screening out and discarding the small seeds) for 

 sowing, in order to secure not only the largest yield of grain and fruit 

 but also to retain the vigour and permanency of the race under high 

 tillage. 



The lesson to be learnt from all these experiments is, that cultivators 

 in Jamaica cannot be too careful in selecting seed for sowing : it should 

 be perfectly ripe, and of the largest size. 



