164 



THE AGRICULTURAL NEWS 



May 25, 1912. 



FRUITS AND FRUIT TREES. 



SELECTION FOR THE LIMA BEAN. 



All account of a method of selection practised for 

 the Lima, or Barbuda, bean {Pliascolus lunatus) is 

 j^iven in Bulletin No. 224 of the College of Agriculture, 

 California University, ifsued last November, and part 

 of this is presented below: — 



A plan of work, looking to the iinprovementof the Lima 

 bean, was begun in the summer of 1908, in co-operation with 

 several farmers. It is expected to continue this work for 

 several years. In the selection of plants, .special attention 

 is being given to earliness where found in high-yielding indi- 

 viduals. It was expected that those plants which blossomed 

 heavily early in the season would also fruit heavily and ripen 

 early. Hence, on the first of July, when fields began to bloom, 

 the earliest and heaviest blossoming plants were marked by 

 means of a piece of lath 2 feet in length, set in the ground 

 beside each plant. Ten thousand stakes were thus set to 

 mark the same number of early blooming plants, the time of 

 selection covering a period of two weeks, and being made in 

 both early and late blooming plants in each field. While 

 there were individual cases in which the early blooming plants 

 did not ripen early, the average time of ripening of these 

 marked plants was earlier than the average of the field. More- 

 over, an advantage was gained in case of selection by marking 

 the plants before the vines became so intertwined as to make 

 it difllcult to recognize individuals. If the early selection had 

 not proved satisfactory, there was still the opportunity of 

 selecting early maturing plants in the fall. But the marked 

 plants being satisfactory as to earliness, it was thought to be 

 of no use to make later selections of other plants. 



The selected plants, although earlier in maturity by 

 perhaps four days than the average of the field, were found 

 at harvest to be apparently lower-yielding than the average 

 of the field. However, this was not entirely unexpected, 

 and as the original purpose had been to make a second selec- 

 tion for yield within the firct selection for earliness, selections 

 being made for 10,000 plants at harvest time. At the time 

 of the first selection in July, earliness of blooming stood 

 almost alone in influencing the marking of plants, except 

 that some attention was given to size and vigour of vine 

 whel-e this did not appear to be due to a difference in room, 

 and hence to available plant food. Vigorous and thrifty 

 plants, which appeared to be so because of inherent character, 



were selected, if blossoming early, and in no case were small, 

 stunted plants selected. At harvest time, however, it seined 

 necessary to pay a great deal of attention to the yield. The 

 plants were pulled, care being taken to separate the vinf s 

 from the vines of surrounding plants, and each was inspected 

 (juickly after being turned over, so that the pods were easily 

 seen. If the pods were found immature, or if the total 

 number of pods was small, it was dropped, except that some 

 plants with a small number of pods were carried along if the 

 plant was very mature, and some very high-yielding plants 

 were carried on, though immature, it being proposed to run 

 two lines of selection, one for eatliness, the other lor yield. 

 In this way, about .3,000 plants were selected out of the 

 original 10,000. 



After a short period of drying, .the pods were picked 

 from each plant and placed in a paper bag. The bags were 

 numbered consecutively, corresponding to cards on which 

 data regarding the number of dry pods, a number of pods to 

 be shelled, and number of pods too immature to shell, length 

 of the vine, and number of pods within 12 inches of the 

 central stem, were recorded. Two numbers were then 

 arbitrarily fixed for each field, one representing number of 

 dry pod.s, the other representing total number of pods, and 

 those plants which did not exceed either of these numbers 

 were discarded. About 1,.500 of the more immature and 

 light yielding plants were discarded in this way. The pods 

 from all the remaining plants were shelled, keeping the lot 

 from each plant separate from all the others. Finally, all 

 but 600 from the original 10,000 were discarded before plant- 

 ing in the spring of 1 909. The seed from these 600 plants, 

 some representing early maturity, some representing high yield 

 and some representing a combination of these factors in the 

 same plant, were grown in rows as foundation stock in 1909, 

 the seed from each plant being planted separately, so that the 

 yield, earliness, and other desirable characters of their produce 

 might be determined. A large number of plants was taken 

 to increase the chances of finding one or more with the power 

 to transmit its characters to the next generation, or to in- 

 crease the chance of isolating mutants. 



The results showed that in the case of pole Lima beans in 

 general, the yield is in proportion to the length of the vine or 

 runners, although it may be said that occasional occurrence of 

 individual plants giving high yield, with a reduced vining ten- 

 dency, would indicate a possibility of reducing this tendency 



