14 BULLETIN 542, U. S. DEPARTMENT OF AGRICULTURE. 



throughout the tree. There were many panicles throughout the 

 tree on which there were no fruits, aside from those which were hand- 

 pollinated. 



Other hand pollinations (all with pollen from the same tree) were 

 made in 1915, as follows: 



]\fvUgoa.-~ Panicle No. 1, all fresh stigmas, pollinated on six successive days. 



Panicle No. 2, all fresh stigmas, pollinated on five successive days. 



No fruits were carried on either one, although there were a few fruits on other 

 parts of the tree. 

 Ma Ida. — -One panicle, on which all fresh stigmas were pollinated on five successive 



days, 243 stigmas in all. No fruits set, and there were only two elsewhere on 



the tree. 

 Kala Alfonso. — All fresh stigmas on one panicle, hand-pollinated on two successive 



days. No fruits set, and none elsewhere on the tree. Perhaps the tree was too 



young; this was its first year of flowering. 

 White Alfonso. — One panicle, all fresh stigmas, hand-pollinated on three successive 



days. Set well, agreeing with the. other panicles on the tree. 

 Amini. — One panicle, all fresh stigmas, hand-pollinated on four successive days. 



One fruit carried, agreeing with several other panicles naturally pollinated. 

 Sandersha. — -Two panicles hand-pollinated on several successive days. Set several 



fruits but carried none; behavior differed in no way from many others natu- 

 rally pollinated. 



In general, it may be said that the quantity of fruit produced in all 

 the above cases agreed with the average of other panicles on the tree 

 which were not hand-pollinated. In other words, no appreciable 

 effect was produced by applying an abundance of pollen to the stigmas. 



In 1916 this experiment was repeated on a small scale, and in addi- 

 tion an attempt was made to determine whether or not cross-pollina- 

 tion would increase the production of fruit; and an experiment was 

 carried on to determine whether fruits would be produced without 

 the pollination of the stigmas. This latter experiment was suggested 

 by the investigations of Belling ' who studied young ovaries of the 

 poly embryonic No. 11 race and found that all the embryos appeared 

 to be adventive, no trace being seen of the fertilized egg cell and no 

 traces of pollen tubes being found in the styles. This suggested that 

 fertilization might not be necessary for the development of these 

 polyembryonic mangos. 



In order to manipulate the flowers more readily and lessen the dan- 

 ger of contamination, all the lower laterals were removed from the 

 panicles operated upon in 1916, leaving only the flowers upon the 

 upper 4 or 5 inches of the panicle. Working with the whole panicle, 

 which may produce 4,000 flowers, it is next to impossible to insure 

 that no anthers are allowed to dehisce or that some of the stigmas are 

 not accidentally pollinated. The panicles wore all inclosed in fine 

 muslin bags stretched over a wire frame attached to the branch below 

 tjie base of the panicle. 



i Boiling, John. Report of assistant in horticulture. Mango. In Fla. Agr. Exp. Sta. Kpt. [1907J/08, 

 p. ex-exxv, pi. 7-10. [1908.] 



