T HE fact that cross-fertilizing species carry relatively large numbers of deleterious recessives in a heterozygous condition has been demonstrated by various investigators and for several species. The results obtained have been used to make inferences or to provide a critical interpretation relative to population structure and size, types of gene action, mutation rates, selective advantage, an...

Present study revealed the importance of endosulfan in mediating stress responses in Sorghum bicolor L. Moench (variety JP-1-1). The seeds treated with different concentrations (0.2, 0.4 and 0.6%) of endosulfan showed a significant decrease in percent germination over control. As the concentration increased, the shoot length, root length and biomass decreased. The amount of chlorophyll-a and pr...

Chlorophyll b is found in photosynthetic prokaryotes and primary and secondary endosymbionts, although their light-harvesting systems are quite different. Chlorophyll b is synthesized from chlorophyll a by chlorophyllide a oxygenase (CAO), which is a Rieske-mononuclear iron oxygenase. Comparison of the amino acid sequences of CAO among photosynthetic organisms elucidated changes in the domain s...

abstract- to investigate the effect of draught stress on water relations, stomatal density, chlorophyll content and yield of rapeseed, an experiment was done with four levels of drought stress including l1 (field capacity, fc), l2 (70% available water content, awc), l3 (50% awc), and l4 (30% awc), within three growth stages- including stem elongation (t1), onset of flowering (t2) and silique fo...

Biogenesis of thylakoid membranes in the conditional chlorophyll b-deficient CD3 mutant of wheat is dramatically altered by relatively small differences in the light intensity under which seedlings are grown. When the CD3 mutant is grown at 400 microE/m2 S (high light, about one-fifth full sunlight) plants are deficient in chlorophyll b (chlorophyll a/b ratio greater than 6.0) and lack or conta...

objective: in order to study the effect of drought stress, salicylic acid (sa) and  jasmonic acid (ja) foliar application on hill reaction and photosynthetic pigments. methods:experiment was done as factorial on the basis of completely randomized design in 4 replications. irrigation in 3 levels (fc,   fc and  fc), salicylic acid in 2 levels (0 and 0.5 mm) and jasmonic acid in 2 levels (0 and 50...

Anabaena variabilis, a blue-green alga lacking chlorophyll b, shows an absence of the major 22 and 24 kilodalton polypeptides which are present in the photosynthetic membranes of Chlamydomonas reinhardi and higher plants. These data are consistent with other investigations which have shown that these polypeptides are associated with chlorophyll b in the chloroplasts of higher plants, and indica...

In an earlier paper (7) the chlorophyll composition of a number of chlorina mutants of barley obtained from D. W. Robertson (10) were described and it was then pointed out that one of the mutants appeared to be entirely lacking in chlorophyll b. Thus, it was of considerable interest to learn whether the chlorophyll b deficiency was affecting the photosynthetic activity of this mutant. Comparati...