A TAXONOMIC STUDY OF ACACIA NILOTIC A COMPLEX IN W. PAKISTAN

Acacia nilotica complex is represented by five subspecies in W. Pakistan, including a new subspecies, A. nilotica ssp. hemispherica Ali and Faruqi, a new combination, A. nilotica ssp. cupressiformis (J.L. Stewart ) Ali and Faruqi and a new record, A. nilotica ssp. subalata (Vatke) Brenan.

CAUSES OF THE FORMATION OF AN ABNORMALLY HIGH PROPORTION OF PROTOTROPHS IN SOME INTERALLELIC CROSSES OF NEUROSPORA CRASS
ABSTRACT:
Causes of the formation of a high frequency of prototrophs in inter allelic crosses of three tryptophan-1 mutants and one tryptophan-3 mutant have been investigated. The high frequency of prototrophs in the inter allelic crosses of the three tryptophan-l mutants follows from the formation of a large number of pseudo-wild spores. But the formation of an abnormally high proportion of prototrophs in the interallelic crosses of the single tryptophan-3 mutant, A30S, cannot be explained on the basis of pseudo-wild formation, action of recombination, accelerating genes, unequal crossing over, reversion of suppressors. It seems that the. tryptophan synthetase formed by the damaged tryptophan-3 locus in this mutant can acquire a functioned configuration as a result of the action of some other genes which act as modifiers.

SOME RARE PLANKTONIC GREEN ALGAE FOUND IN EAST PAKISTAN
ABSTRACT:
In this paper the planktonic species of fifteen genera belonging to Chloro- phveeae have been described and illustrated with the addition of a new

STUDIES ON THE AGARICS OF DACCA, EAST PAKISTAN. III. WHITE SPORED AGARICS
ABSTRACT:
This paper deals with the study of white spored Agarics of Dacca, namely, 3 species of Lepiota, one species of Panus and one species of Pleurotus. All these species including the genus Panus have been recorded for the first time from East Pakistan.

GENETIC STUDIES ON YIELD AND YIELD COMPONENTS OF BRAS SICA CAMPESTRIS L.
ABSTRACT:
Inheritance of yield and its associated characters were studied in two varietal crosses involving three varieties of Brassica campestris L. Heritahility estimates ranged from 81 per cent for seed yield per plant in cross-1 to 19 per cent for 10-fruit weight in cross-2. Transgressive segregation in both directions was observed in seed yield per plant and fruit length in cross-2 and in seed weight per 10 -fruit and number of fruits per plant in cross-1. Over- dominance was observed in 10-fruit weight and 100-seed weight in both the crosses and number of seeds per fruit and number of fruits per plant respectively in cross-1 and cross-2. The estimates of dominance (hj) gene effects were mostly larger than the additive (d) gene effects and were significant in almost all the characters. Epistasis was detected by chi-square

A PRELIMINARY SURVEY OF ASPERGILLUS SPECIES FROM KARACHI (WEST PAKISTAN)
ABSTRACT:
A preliminary survey of Aspergillus species from Karachi was undertaken. The sources from which these were isolated consist of soil, air, spoiled fruits and leather products. Malt extract agar and Czapek-Dox agar with Rose Bengal (1 :30,000) were utilized for culturing these fungi. A total of 23 species were recorded. Out of these, Aspergillus near flavo- furcatis, A. puniceus, A. unguis and A. variecolor have been reported for the first time from Karachi. The species not reported from West Pakistan as such are A. near flavo-furcatis, A. puniceus '“'and A. variecolor. Brief descriptions of only these three species have been provided. It has been ascertained that out of a total of 49 species of the genus Aspergillus reported by the previous workers, only 23, beyond doubt, are the accepted ones. The remaining 16 species include synonyms, probable synonyms and non-recognisable