Volume 59, Issue 5
May 1964, pages 245-295
pp 245-251 May 1964
Parallel experiments using natural populations were conducted to find out the variability of values of organic production obtained by two different C14 stock solutions, standardization techniques and counting systems as well as the relative efficiency of three types of filters. The results indicate that a uniform method of standardization of stock solution and a careful selection of filters are necessary more than anything else if values of organic production obtained by different workers are to be compared.
pp 252-258 May 1964
The present work deals with the changes during the development of the Pseudocarp inAnacardium occidentale, which is morphologically the pedicel and the disc.
The number of bundles increases from the base towards the distal end in a peculiar way, which has been described in detail. Some of the bundles appear to arisede no vo in the pith whereas the others form a continuous system from base to top.
The development of resin ducts in the pseudocarp is described in detail. They develop lysigenously.
The growth of the pseudocarp is also dealt with. There are three factors which helps in the enlargement of the pseudocarp (1) segmentation and enlargement of the vascular bundles, (2) the enlargement of the parenchymatous cells in the cortex and pith and (3) the increase in number of the resin ducts and their enlargement.
The amount of tannin contents in the cortical and medullary cells was also studied. The tannin contents increase gradually up to the time when the pseudocarp is 22–25 mm. in diameter. Thereafter, they reduce gradually and disappear, completely.
pp 259-262 May 1964
The coefficients for relative growth differ in the two sexes. The implantation of the androgenic gland into the female transforms into the male, and during this process the relative growth coefficient for the abdomen changes progressively during the post-operative intermoult periods. Finally the allometric coefficient assumes nearly the value characteristic for the normal male.
pp 263-286 May 1964
pp 287-295 May 1964
1. Screening tests were carried out with 490 early duration varieties to isolate varieties resistant to blast disease of rice.
2. On the basis of the reaction of the varieties in the seedlings, post-transplanting and neck-infection stage, four varieties have been selected finally as resistant and eight as moderately resistant to blast disease of rice.