http://localhost:80/xmlui/handle/123456789/16574 2026-02-24T00:37:07Z http://localhost:80/xmlui/handle/123456789/16913 Title: A CLADISTIC ANALYSIS OF CALANDRINIA (PORTULACACEAE) Authors: SYEDA SALEHA TAHIR; PETER S. ASHTON Abstract: The cladistic relationship among 34 species of the genus Calandrinia H.B. et. K. (Portulacaceae), en¬demic to Australia were analysed for 22 binary attributes, by using "PHYSYS" computer program. The driteria used to assign evolutionary polarity of attribute state is discussed in detail. In all the Phenograms four main groups come out fairly clearly. The major difference in the trees produced by PHYSYS are the changes in the position of a few taxa, within the major group. The present paper provides data on variation and correlations in seed and pollen characters, and also synthesized detailed morphological relationships. The species having questionable position in some groups are discussed in the light of their unique characters. 1989-06-20T00:00:00Z http://localhost:80/xmlui/handle/123456789/16912 Title: STUDIES IN THE POLLEN MORPHOLOGY OF ARNEBIA SPECIES (BORAGINACEAE) FROM PAKISTAN Authors: QURESHI, QAISER; S. SHAHID SHAUKAT Abstract: A palynological study of 9 species of the genus Arnebia from Pakistan was carried out. The pollen were characerized by having two endoapertures per ectoaperture and a well developed costae with rectangular to constructed rectangular equatorial outline and echinate tectum. Using Principle Component Analysis (PCA) and Cluster Analysis of various pollen characters a correlation of the style length and pollen size was worked out. 1989-06-19T00:00:00Z http://localhost:80/xmlui/handle/123456789/16899 Title: CONTROLLING ELEMENTS INDUCING MUTATIONAL CHANGES AT THE PAL LOCUS IN ANTIRRHINUM MAJUS Authors: K.M. ASLAM Abstract: In Antirrhinum majus the pal-rec-low-o is a repressed state of the pallida-recurrens allele. In heterozy¬gous condition, especially with pal-tub pal-tub tester, its mutation frequency increases from few tiny spots to very clear sectors of mutability on a recessive colourless background. This particular evocation of the pal-rec¬low-o allele is considered to be dependent on the presence of a regulatory element Pr. In the absence of such a regulatory element, the pal-rec-low-o exhibits stable expression owing to the effect of a repressor Rp residing at or near the locus. However, pal-tub regulatory element could be inactive, when inactive, can be made trans-active by introducing a fresh regulator which may segregate at meiosis. 1989-06-18T00:00:00Z http://localhost:80/xmlui/handle/123456789/16893 Title: A STUDY OF NATURAL REGENERATION OF JUNIPER US EXCELSA M. BIEB, IN BALUCHISTAN, PAKISTAN Authors: MOINUDDIN AHMED; IMTIAZ AHMED; PERVEZ IQBAL ANJUM Abstract: Regenerating seedlings from 60 mature stands on Juniper track in Baluchistan ranged from zero to 219 ha-' with a mean of 52 ha-'. Seedling density and basal area (P < .001) and tree basal area and seedling density (P < .05) were significantly correlated indicating that seedlings are shade loving. Highest average seedling density and basal area were recorded from West facing slope. Size frequency distribution of seedling showed a wave of recruitment in addition to past and future trends of the seedling populations suggesting that Juniper forests are not deteriorating. 1989-06-16T00:00:00Z