Salinity and density effects on demography of atriplex triangularis willd
ABSTRACT:
The effect of density-dependent and density-independent factors in regulating the resource allocation , reproductive effort, and fecundity of atriplex triangularis populations were studid in field and laboratort conditions. Total biomass production and reproductive output of A. triangularis varied with changes in soil salinity and plant density. At low soil salinity , where plants produced greater biomass and had higher reproductive output, increased density resulted in a substancial decline in biomass production and a 500 fold lower reproductive output. At higher soil salinities , density- independent factors caused lower biomass production and reproductive output. Small plants were produced under three conditions , containing 57 seeds per plant . increased density caused a five fold reduction in biomass production and reduced fecundity to only 17 seeds per plant. Increase in density resulted in significant decreases in plant size but the

Germination , growth and ion regulation in prosopis juliflora (Swartz) DC. Under saline conditions.
ABSTRACT:
Germination and seedling growth of prosopis juliflora was tested using various dilutions of amended sea water. The plant exhibited high salt tolerance at germination as well as at the growth phase .fifty percent reduction in plant biomass corresponded to EC1w : 21.3 dS.m- 1 . it responded to salinity through K+ selectivity during ion influx and exclusion of Na+ from the leaves by retaining it in the roots. Ca++ content decreased in all plant parts under saline conditions likewise, concentration of Mg++ declined in roots and did not change in stem but increased in leaves. The mechanism of salt tolerance is discussed with respect to ionic balance suggesting a wide ecological amplitude for P.juliflora.

Phytosociology of the plains of quetta district.
ABSTRACT:
Sixteen plant communities recognized on the basis of index of similarity were grouped into 4 steppe types (artemisis maritime steppe, haloxylon griffithii steppe, alhagi maurorum steppe salsola hbaryosma steppe) which correlated with the edaphic factors . individual communities in each steppe type further segregated on the basis of edaphic factors. The total coverage as well as species diversity tended to be relatively high in protected areas and graveyards . the characteristic species of these areas

Structure , composition and pattern in avhyranthes aspera L. dominated ruderal vegetation in the suburbs of karachi
ABSTRACT:
The analysis of achyranthes aspera dominated stands revealed that 45 species were associated with a mean number of 9.54 +- 1.02 species per stand though most of them were of minor importance. A.aspera itself had an average importance value index of 126.97 (range = 103.9- 177.4). species diversity of stands was low and the relative abundance pattern was geometric. Species diversity was predominately a function of equitability . the imporatance value of A. aspera was positively correlated with the humus content and proportion of fine sand in soil and negatively correlated with coarse sand percentage. All stands were associated with basic, non-saline and relatively calcareous soils. Significant negative associations were indicated with cenchrus biflorus , leucos urticifolia and

Palynological studies in the sub genus coprosma (rubiaceae )from new Zealand.
ABSTRACT:
Ten species of the sub genus coprosma (rubiaceae ) have been studied palynologically, TEM was more informative where different components of the exine provide taxonomic characters. The useful characters for taxa differentiation include pollen size (the section coprosma) and the thickness of exine components.

Pollen studies in the primula species (primulaceae) found in Pakistan with special reference to taxonomy
ABSTRACT:
Three basic pollen types, namely auricular , farinose and veris are found in primula . the species occurring in Pakistan are catergorised and the relationship between various species discussed. SEM for the majority of Himalayan taxa has been attempted for the first time.

Chromosomal races of themeda anathera from Pakistan.
ABSTRACT:
Chromosome number and meiotic pairing of three varieties of themeda anathera (Nees) hack, from Pakistan show diploids , aneuploides and eupolyploids all with

Formation of plantlets in cultured anthers of nicotiana tabacum CV. virginica
ABSTRACT:
Anthers of nicotiana tabacum cv. Virginica were cultured and the development of pollen grains studied. A large proportion of pollen grains degenerated in culture , the surviving ones belonging to mitotic and binucleate class producd plantlets which originated from’S’ grains. Cold pretreatment of anthers increased both the number of anthers producing plantlets and the number of plantlets per anther. Dividing the culture period into an initiating and a developmental stage proved beneficial. Addition of mannitol and glutamate gave maximum number of plantlets, absence of which reduced yield. Role of mannitol and glutamine in the development of plantlets from pollen grains in anther culture is discussed.

Callus induction and plantlet formation from kallar grass 9leptochloa fusca )
ABSTRACT:
In studies on callus induction from seeds and seedling explants 32% seeds produced calli when BA (10-7 M) + 2,4-D (10-5 M)+ NAA (10-6 M ) were used. Mode of regeneration was embryogenesis in a combination of BA (10-7 M )+NAA(10-6 M ) +2.4-D (10-6 M) +IAA (10-6 M ). Numerous small embryoids developed with in the

Leaf callus culture of rauwolfia serpentina
ABSTRACT:
Young leaves of rauwolfia serpentine baill, inoculated on MS medium supplemented with NAA @ 1 mg/l with 10mg/l K and and 10% CM under 24 h light induced callus while 2,4-D induced callus under 16 h light . callus induction and its growth was more on explants taken from in vitro raised seedlings on 2,4-D @ 1mg/l or NAA @ 1 mg/l +10 mg/l K and 10% CM under 24 h light. On subculturing the callus exhibited good growth similarly leaf callus growth on AM medium containing NAA, BAP, K, AS and 2,4-D with 1 g/l of CH showed excellent growth . the cultures on MS contained 0.0249-0.0281 % ajmaline , and 0.041 % on AM medium.

Variability for some quantitative traits in soybean
ABSTRACT:
The magnitude of genetic variability , heritability and genetic advance among 36 varieties of soybean was studied . considerable genetic variability was observed for pods per plant, plant height and grain yield per plant. Yield could be considerably improved through intensive selection pressure based on number of pods and number of branches per plant .

Effect of various light insensities on photosynthesis and nodulation in soybean
ABSTRACT:
Influence of 5000 and 10,000 hux intensities on photosynthesis , leaf area, dry matter and nodulation in nodulated and non-nodulated soybean (glysine max CV. Covernia-5) was investigated. High light intensity increased rate of

Hydrogen uptake by the nitrogen fixing root nodules and nodule homogentaes of coriaria nepalensis
ABSTRACT:
Nitrogen fixing root nodules of coriaria nepalensis consumed hydrogen pn incubation with a gas mixture containing hydrogen , indicating an uptake hydrogenase activity . the H2 uptake by the excised nodules varied throughout the year and was highest (2.16 mole H2 consumed g fresh nodule wt-1 .hr-1.) in may. The enzyme activity was detected in vesicle cluster suspensions of the endophyte (20 um residue) as well as in the 20 m filterate fraction of the nodule homogenate.

Structure and development of colleters in aganosoma caryophyllata G. DON.
ABSTRACT:
In aganosoma caryophyllata , colleters are present on the basal adaxial side of the petiole, bract and calyx . these finger shaped structures are clearly divisible into head and stalk . the colleters are developing from a group of epidermal and hypodermal initials a mature colleter consists of a central core of parenchymatous cells surrounded by palisade like epithelial cells. Epithelial cells are externally coated with thick cuticle and contain a single nucleus with abundant cytoplasm. A characteristic

Studies on the sterols of a brown seaweed iyengaria stellate from pakistan
ABSTRACT:
The marine benthic brown alga iyengaria stellate (borg) borgesen , collected from the coast of Karachi was studied for its sterol composition . analysis of ethyl acetate fraction of the methanolic extract of the seaweed by gas liquid chromatography-mass spectrometry revealed the presence of cholesterol, 24- methyl cholesterol ans ergosterol. The last two sterols are being reported for the first time from a brown seaweed.

Ccemical constituents of red algae acanthophora dendroides and halymenia porphyroides
ABSTRACT:
The ethyl acetate fraction of methanolic extracts of acanthophora dendroides Harvey and halymenia porphyroides borgesen yielded a mixture of fatty acids and cholesterol as a major compound, while 7-oxocholesterol was a minor constituents of H. porphyroides , which is being reported for the first time from any red alga. The fatty acid constituents of both seaweeds analysed by GC/MS, revealed the presence of 7 saturated and 8 unsaturated fatty acids. Hexadecanoic acid and its methyl ester were found as major fatty acids in both algae.

The influence of chlormequat on growth of raya (brassica juncea L.)
ABSTRACT:
Brassica juncea seeds soaked in 1000 ppm chlormequat solution for 6 h increased seed germination, number of branches , flowers , pods and yield , while pod length , pod diameter , seed per pod, seed weight and oil contents were nonsignificant .

Effect of boiling on the in-vitro protein digestibility of four different pulses
ABSTRACT:
In-vitro digestibility of mung ( vigna radiate) , mash ( vigna mungo ), masur ( lens culinaris ) and gram (cicer arietinum ) in raw and boiled states was undertaken , mung had highest crude protein content 926.18%). The digestion with pepsin followed by pancreatin indicated a significant decrease , from 33.41 to 49.68% , in the digestibility of all the boiled pulses. The highest digestibility among the unsoaked-raw and soaked –raw pulses was 75% and 78.88% , respectively for gram. In unsoaked –boiled and soaked-boiled pulses highest digestibility was 32.68 and 38.46 % , respectively for masrur , soaking the pulses prior to boiling improved digestibility . the hydration coefficients of all the pulses , except gram was inversely related to boiling time, which in turn showed a positive correlation with digestibility.

Mycorrhiza in jute production
ABSTRACT:
Association of mycorrhiza with jute plants ( corchorus sp ) is elucidated .a species of glomus is considered forming mycorrhizal association with jute plants . the effect of mycorrhiza on the growth of jute plants and production of jute fibre is presented.