Distribution of Growth in the Apical Region of the Shoot ofLupinus albus

Publisher Website
Google Scholar
Abstract
The purpose of the investigation is the determination of the volumes and numbers of cells of the meristematic dome and of each of the first 7 primordia and internodes at the apex of the shoot of Lupinui albus . This system occupies a zone which is about 0·4 mm. in length. Techniques are described for dissecting the region in which the observations are made, for determining the numbers of cells and the volumes of the several fragments. From the number of cells and the volume of each fragment an average cell volume it calculated. It is shown that in the midphase of the plastochron the dome contains 3,500 cells and has a volume of 1·6 ×10 −3 mm. 3 , the first primordium contains 1,630 cells and has a volume of 0·38 ×10 −3 mm. 3 , and the first intemode contains about 700 cells and has a volume of about 1·4 ×10 −3 mm 3 The number of cells and the volume of the primordium increase exponentially with increasing plastochron age, and the seventh primordium contains 26,000 cells and has a volume of 20·9 × 10 −3 mm 3 The seventh intemode contains about 5,000 cells and has a volume of 8·6×10 −3 mm 3 The average cell volume in the dome is 4·7 × 10 −7 mm. 3 in the first primorndium it is 2·3 × 10 −7 mm. 3 and in the first internode it is 20·9× 10 −7 mm. 3 In the seventh primordium the average cell volume increases to 7·9 × 10 −7 mm. 3 In the internodes there is little, if. any, change in cell volume from the first to the seventh of the series. The significance of these changes is discussed.

This publication has 2 references indexed in Scilit: