COMBINING ABILITY IN VIGNA-MUNGO (L) HEPPER
ABSTRACT:
Combining ability analysis was conducted for grain yield and yield Components viz., plant height. branches per plant, pods per plant, pod length, seeds per pod, 100 grain weight in a five parent diallel population of mash (Vigna mungo) including parents, F1's and reciprocals. Non-additive gene action (dominance or epistasis) contributed the major portion in total genetic variance for all the plant characters studied.Significant reciprocal effects were also observed for all the characters which indicated the importance of maternal contribution iii the performance of hybrids. Therefore a biparental mating among the selected F2 segregants followed by selection in advanced generations, F6 or later, is suggested. The genotype 87/88 proved to be the best general combiner for pods per plant and grain yield and could be exploited in future mash breeding programme to develop high yielding varieties.

HYBRID VIGOUR IN INTERV ARIETAL CROSSES OF UPLAND COTTON
ABSTRACT:
Heterosis studies were undertaken in seven intervarietal F1 hybrids of Gossypium hirsunum L, for number of sympodia, mimber of monopodia, number of bolls, boll weight, ginning outturn percentage, staple length and seed cotton yield. Mean squares revealed that all the hybrids and their parents were significantly (P < 0.01) different for all the characters except boll weight. All the hybrids manifested hybrid vigour over their mid parent values for all the characters under study except monopodia per plant, where four hybrids also exhibited positive heterotic effect. Majority of the hybrids transgressed over their better parent values and all the hybrids showed heterobeltiotic effects for seed cotton yield per plant. The hybird of Qalandari X CIM-109 out yielded the performance than the other crosses, the values being 100.56 and 89.24 % in comparison to their mid and better parent values respectively. TIle results indicate that all the cross combinations could be utilized for getting higher yield as hybrid production.

HETEROSIS IN INTERSPECIFIC COTTON HYBRIDS
ABSTRACT:
Both F1 and F2 hybrids of cotton manifested considerable amount of heterosis against the parents. The F2 hybrids which produce more quantity of seed as compared to F1 may be considered for hybrid cotton production. The average heterosis of F2s over the parents recorded was 16.44% in yield, 9.68% in bolls/plant, 16.21% in seed index, 1.34% in lint and 3.45% in staple length. In all the crosses, observed inbreeding depression was greater than what was expected based on coefficient of inbreeding. The discrepancy between the observed and expected depression could be due to factors like linkage disequilibrium, epistasis and ploidy level.

EFFECT OF AQUEOUS EXTRACTS AND LEACHATES OF ANTHERS OF CERATONIA SILIQUA L., ON THE INHIBITION OF LETTUCE SEED GERMINATION
ABSTRACT:
Aqueous extracts and leachates of young, mature, and senesced anthers of Ceratonia siliqua were tested for their inhibition of lettuce seed gemlination. Only senesced anthers was found to contain substantial amounts of germination inhibitors. Isolation of the inhibitors from the anthers revealed the inhibitors to be soluble in water, methanol, ethanol, ethyl acetate and was acidic in nature. Kinetin and GA3 were found to counteract the inhibition of the aqueous extract and leachates of the senesced anthers. Little,loss in the inhibitory activity of the aqueous extract occured even after subjecting the anthers to the highest soil temperature of 80°C for 60 minutes, which indicated that the inhibitors were not proteinaceous.

COMPARISON OF SALT STRESS RESPONSIVE PROTEINS IN ATRIPLEX AMNICOLA ANTIBODIES AND TWO ECOTYPES OF LEPTOCHLOA FUSCA (L.) KUNTH.
ABSTRACT:
Three salt tolerant plant types viz., Atriplex amllicola, Leptochloa fusca (L) Kunth. (Pakistani origin) and Leptochloa fusca (L) Kunth (Australian origin) were used for a comparative study of altered gene expression under salt stress. The plants were aseptically grown in hydroponic medium and exposed to increasing levels of salt starting from 50mM NaCI to 500mM NaCI. Under these stress treatments there was variable expression of a number of proteins as revealed by SDS-PAGE. Specific activities of plant GDH, GOGATand GSin response to salt stress were also determined. Klebsiella sp., NIAB-l, adiazotroph isolated from roots of Leptochloa fusca (L.) Kunth was also exposed to 50mM NaCI to 1000mM NaCI treatments, to examine salt responsive protein profiles. Blots of protein profiles from the three plant types were probed with antibodies raised against p-20 of Atriplex amnicola and p-26 of Klebsiellasp., NIAB-1, to reveal common epitopes among the salt responsive proteins.

RESPONSE OF PHRAGMITES AUSTRALIS TO WATER STRESS FROM FLOODING TO DROUGHT
ABSTRACT:
 Leaf samples of Phragmites australis collected from five locations varying from totally flooded to dry regime showed a sharp decrease in the fresh leaf water content of the plant from flooding to dry locations accompanied by an incomparable decrease in OP. This incremental osmotic regulation occurred due to the accumulation of soluble sugars, amino acids, proteins, proline and the nutrient elements K, Na, Ca, Mg and Fe. Low OP under flooding was attributed to the condensation of sugars and amino acids into polysaccharides and protein. Both drought and flooding conditions n:sulted in the accumulation of polysaccharides, protein and proline.

EFFECT OF SALINITY ON GROWTH, SEED YIELD AND NODULATION OF CICER ARIETINUM
ABSTRACT:
Growth, seed yield and nodulation of Cicer arietinum were compared at 0, 0.1, 0.2, 0.4, 0.8, 1.2, 1.6 and 2.0% levels of NaCI salinity in sandy clay loam. Fresh weight of shoots and roots after 8, 12 and 15 weeks salinity treatment, generally decreased with increasing salinity levels. Compared to vegetative growth, reproductive growth was more affected since pods were formed upto 0.4% NaCl levels, whereas, seeds were formed at NaCl level of upto 0.1%only. Numberofnodule per plant, nodule weight and nodule size decreased with increasing salinity levels.

PHYTOSOCIOLOGY OF THE VANISHING TROPICAL DRY DECIDUOUS FORESTS IN DISTRICT SWABI, PAKISTAN, I.A COMMUNITY ANALYSIS
ABSTRACT:
The vegetation of 20 different graveyards in District Swabi was sampled quantitatively. Three main communities: Dalbergia sissoo-Melia azedarach, Ziziphus mauritiana with 2 subtypes, and Acacia modesta with 5 subtypes, were recognized on the basis of similarity indices, importance values and floristic composition of the stands. A. modesta community was widely distributed in the area. The first two communities represent secondary succession in the area. The vegetation of all the stands was stratified into tree, shrub and herb layers. The variation in the dominant species was dueto edaphic and biotic disturbance. It is suggested that the existing vegetation might funher change due to underground seepage of water from nearby Tarbela dam. A vegetation profile of all the communities is given.

SURVIVORSHIP PATTERNS OF SOME DESERT PLANTS
ABSTRACT:
Survivorship pattern of some common summer annuals and perennials showed quite varied mortality patterns which can be tentatively grouped, according to Deevey system of classification. Annuals like Indigofera cordifolia and I. hochesttetri showed a gradual decrease in number of plants after initial lengthy recruitment period and appeared close to type II Deevey curve. However, annuals like Eragrostis ciliaris, Aristida mutabilis, Cynodon dactylon and Tephrosia strigosa showed little mortality at the early phase of life cycle and high mortality at the time of flowering and fruiting following type I Deevey curve. Perennials like Blepharis sindica, Senna holosericea, and Corchorus depressus initially showed a higher level of mortality leaving only few seedlings to continue their life cycle thus following type 3 Deevey curve.

RELATIONSHIP OF SEED BANK TO PLANT DISTRIBUTION IN SALINE ARID COMMUNITIES
ABSTRACT:
Species of seed bank and those occurring in vegetation were compared for six desert halophytic shrub communities. Perennial shrubs like Suaeda fruticosa, Haloxylon recurvum, Cressa cretica and Salsola baryosma dominated the six communities studied. Communities also showed very low species diversity. The seed bank was represented by a large number of species as compared to the species present in the vegetation, indicating a poor relationship between seed bank and vegetation. S. fruticosa maintains a persistent seed bank thereby dominating the seed bank flora of almost all communities irrespective of the dominant species. All other perennial halophytic species studied showed a transient nature of the seed bank. Monthly seed bank data was collected for 2 halophytic species for 12 months. Presence of H. recurvum, S. fruticosa and C. cretica was higher in the seed bank after seed dispersal and except for S. fruticosa seeds, the number of all other species declined substantially in the soil.

Life form and leaf size spectra of the plant communities of diverse areas ranging from Harnai, Sinjawi to Duki Regions of Pakistan.
ABSTRACT:
The taxonomy and morpho-anatomy of Dilophus fasciola (Roth) Howe var. repens (J. Agardh) Feldmann and Spatoglossum australasicum Kuetzing is reported for the first time from the coast of Karachi.

Addition to the species of Dilophus J. Agardh and Spatoglossum Kuetzing (Phaeophyta-Dictyotales) from the coast of Karachi, Pakistan.
ABSTRACT:
Using TLC patterns and growth response to tannin, the profiles of secondary metabolites in 5 species of Fusarium viz., F. anthophilum, F. proliferatum, F. subglutinans, F: scirpi and F. sporotrichioides isolated from wheat, corn and pearl millet is presented as additional criteria for species identification.

Profiles of secondary metabolites in species of Fusarium
ABSTRACT:
Extra early pigeonpea genotypes selected from ICRISAT materials planted at the National Agricultural Research Centre, Islamabad were found infected by a pod rot disease during September-October, 1990. The disease appeared as water soaked lesions which subsequently developed into a wet rot affecting both young and mature pods showing luxuriant whitish growth with black headed pin like sporangia around the pods. The pods damaged by insects were more affected than non-damaged pods. Withered and detached flowers also showed fungal growth. Pods near maturity were more susceptible than the young pods specially under humid conditions. The fungus isolated in pure culture on PDA medium was identified as Choanephora cucurbitarum (Berk and Rav.) Thaxter (Stevens, 1913). Detached healthy pods of pigeonpea cultivar ICCP-83015 surface sterilized with 0.5% sodium hypochlorite solution for 1.5 minutes, followed by washing in sterilized distilled water were dipped in a conidial suspension of C. cucurbitarum (6.5x104 conidia/ml) and placed in sterilized Petri plates at room temperature (24±2°C) developed characteristic symptoms of the disease. There does not appear to be any previous report of C. cucurbitarum on pigeonpea in Pakistan. Pod rot of pigeonpea caused by C. cucurbitarum has been reported from India (Misra & Mehra, 1969). The fungus has been reported to parasitize Luffa acutangula Roxb., (Ghaffar & Kafi, 1968), Capsicum annum L., (Mirza & Qureshi, 1978), Vigna unguiculata (L.) Wilp (Bashir et al., 1985) and Vigna radiata (L.) Wilczek (Alam et al., 1984).

Choanephora pod rot of pigeonpea in Pakistan.
ABSTRACT:
Cotton (Gossypium hirsutum L.) is one of the most important crop of Pakistan which accounts for 60% of the export product of the country. In the last few years cotton leaf curl disease has acquired epidemic proportions in Pakistan and has seriously threatened cotton production. The characteristic symptoms of the disease are severe leaf curling, thick dark veins and enations which sometimes differentiate into cup shaped leaf-like structures on the underside of the leaf (Fig 1a). Whitefly (Bemisia tabaci) was suspected as the insect vector of cotton leaf curl disease. Whiteflies maintained in the controlled conditions were used for insect transmission of the disease from cotton to cotton and from cotton to tobacco (Nicotiana tabacum). The symptoms developed on cotton and tobacco were similar to leaf curling in cotton plant with thick dark veins and development of cup shaped structures on underside ofleaf (Fig.1b).

A whitefly - transmitted Geminivirus associated with colton Leaf Curl disease in Pakistan.
ABSTRACT: