Factorial allelopathy : stress of aging , possible mineralization , nitrification , and individualistic pressure of different tree species in a forest community
ABSTRACT:
Herbaceous biomass soil moisture, and soil factors pH, P,N, Ca , K MG, AND MN, when compared from under sycamore , hackberry, red oak, and white oak trees were significantly variable. The differential herbaceous growth pattern did not correspond with soil moisture or variability of different soil factors under different tree species. The amounts of available ammonium and nitrate nitrogen were inversely related to the amounts of total nitrogen under all trees . ammonium nitrogen was always found to be significantly higher than nitrate nitrogen in all cases . sycamore , hackberry , red oak , and white oak trees exerted differential allelopathy influence on their understoroy vegetation , inhibition of nitrification and mineralization . all species exhibited greater allelopathic impact with aging stress of the trees . many phytotoxins were isolated from sycamore , hackberry , red oak, and white oak plant material. Phytotoxins identified were mainly phenolics, flavonoids, hydrolysable and condensed tannins

On the vegetational dynamics of calcareous hills around karachi
ABSTRACT:
Taken together , the findings reported in this paper suggest the prevalence of a progressive succession which seems to be governed initially by extrinisic factors but subsequently largely by the intrinsic properties of the plants . the major

Studies on the organization of genes controlling lysine biosynthesis in neurospora
ABSTRACT:
Thirty eight lys-5 mutants have been studied for interallelic complementation . they fall into 17 groups which cn be arranged on a complementation map comprising 8 complons. While the defects in 16 groups permit a linear

Germinatiob and growth (inhibitors in the fruits of pittosporum tobira ait, during ripening.
ABSTRACT:
Germination and growth inhibitor (s) in different fractions of ripening fruits of pittosporum tobira was studied . both unripe and ripe fruits contained germination and growth inhibiting substance (s) in the water-soluble, acidic and neutral fractions as compared to unripe fruits, germination and growth inhibitor (s) increased 2-3 folds in the ripe fruits . it is suggested that the increase in acidic inhibitor (s) during ripening may reflect the increase in the level of endogenous ABA-like substances.

Seasonal changes in nitrate reductase activity of soybean leaves in relation to their position in plant canopy
ABSTRACT:
Nitrate reductase (NR) activity of field grown soybean leaves in relation to their position in the canopy showed that fresh leaf weight was higher in centrally located leaves as compared to those at the bottom or top of the plant, nitrate reductase activity per g fresh weight per hr was maximum at leaf position 4 which gradually declined in leaves located below or above . an average sample rom a given location showed greatest fresh weight and nitrate reductase activity on early dates

Effect of saline soils, amended with calcium nitrate on the growth and chemical constituents of potato plants.
ABSTRACT:
Saline soils of different regimes were amended with calcium nitrate to elucidate its effect on the growth and chemical composition of potato plants. The effects of salinity on the foliage growth were more pronounced in cv. Rheinhort than in the patrones and cardinal . chlorophyll content increased upto 0.8% amended salinity. Accumulation of oganic solutes (sugars, proteins, proline) in plants under salt stress suggests the basis of osmoregulation for building up salt tolerance. The ability of potato plants to discriminate between Na4 and K9 uptake from saline soils provides a criteria to forecast salt tolerance . on the basis of yield .cv. rheinhort is considered as highly tolerant , patrones as tolerant and cardinal as moderately tolerant to salinity. TGA level was significantly reduced by the amendmentsn under saline conditions.

Effect of some growth regulators on plant growth . tuber initiation , yield and chemical composition of potato (solanum tuberosum L)
ABSTRACT:
Effects of some growth regulations on growth . yield and composition of potato (solanum tuberosum L) have been studied GA3 increased about extensions , leaf area, number of leaves, stolons and tubers but decreased dry matters of stem , leaf and tuber . IAA and K increased dry matters of stem nd leaf but decreased leaf number and leaf area, the number of stolons and tubers either decreased or were not affected . yield of tuber increased

Cotton yield and weed density and diversity in response to pre=emergence application of herbicides in cotton field.
ABSTRACT:
Weed density and diversity were measured at various periods of the growth of a cotton crop following pre-emergence application of 2 and 4 kg/ha prometryne and fluometuron . application of 2 kg/ha prometryne resulted in decreased weed density but relatively higher weed species diversity and a significant improvement in cotto yield; however, application of prometryne at 4 kg/ha gave contrasting results. Fluometuron, despite reducing weed density and elevating weed diversity did not increase the crop yield over the controls presumably due to slower rate of dissipation and consequently higher residual avtivity on the cotton field.

Effect of AL and FE on the growth and mineral content of barley.
ABSTRACT:
The dry matter of barley tops and roots decreased at high Al-treated plants, while the roots were short, thick and spotted brown in colour . chlorosis observed on the Al treated plants when the sources of Fe were ferric. Plants applied with ferrous iron did not show any such chlorotic

Water soluble protein from fagonia cretica linn.
ABSTRACT:
Water soluble protein was isolated and purified from the water extract fraction of dried fagonia cretica plant. The acid hydrolysate of the material showed the presence of phosphate. Sugar and amino acids in the molar ratios of lysine 1; threonine 2; aspartic acid 3; serine 3; glutamic acid 3.

A rapid method for chlorophyll determination
ABSTRACT:
A rapid method for colorimetric determination of chlorophyll a,b and total chlorophyll has been suggested by using a single wavelength-645 nm.