ONTOGENY AND ANATOMY OF THE FLOWER OF LIMNOCHARIS FLAVA (BUTOMACEAE)

The flowers of Limnocharis flava (L.) Buch. are borne in an indeterminate umbel and each consists of three sepals, three yellow petals, and about 18 carpels surrounded by numerous stamens and staminodia. The androecium is centrifugally developed, and the last-formed members are staminodial; it is supplied by branching vascular systems. Carpels arise almost simultaneously, and a prominent residual floral apex remains. The carpels are partially conduplicately closed and are also primitive in possessing laminar placentation and in lacking differentiation of a style. The gynoecium is essentially apocarpous, but there are slight fusions of adjacent carpels near their ventral margins where they are attached to the receptacle. It is suggested that the Limnocharis flower is the most primitive in the family.     

Effect of nifedipine administration on the functional capacity of neutrophils

Administration of nifedipine to mice over a period of six months caused a significant (p<0.05) decrease in neutrophilic functions viz superoxide generation, coupled to NADPH oxidase activity as well as NADPH production by HMP shunt. Properties like chemotaxis and phagocytosis showed a similar decrease. From this study, it is seen that nifedipine causes neutrophil functional abrogation which is therefore an apparent concern for the prolonged usage of the drug. However, relevance of the mouse model to clinical situation needs further investigation.     

Flower production,male sterility and berry setting in andigena potato

Summary Unlike tuberosum, andigena potato germ plasm exhibits a high degree of genetic variation in morphological, biochemical and reproductive traits. Sixty-five percent of the 565 genotypes comprising 145 accessions of Solanum tuberosum ssp. andigena obtained from Argentina, Bolivia, Chile, Colombia and Peru remain totally vegetative and never develop any floral bud when cultivated in northern India. In 18% of genotypes, the floral buds develop but they drop off from the plants prematurely. Thus, 83% of genotypes do not develop mature flowers. The frequency of such genotypes is maximum in the Bolivian genotypes. Whereas 17% of genotypes produce mature flowers, only 2% develop berries. The highest proportion of floral bud formation and their subsequent development and differentiation into mature flowers occur in Peruvian and Colombian genotypes. Partial to high male sterility occurs in 93% of the flowering genotypes; their pollen sterility ranges from 15% to 91%. Seven percent of the flowering genotypes are completely pollen sterile. The male sterility is expressed variously, ranging from structural to sporogenous types. The floral bud formation, its development and retention to maturity, pollen and ovule functionability and fruit development are under the control of a large number of genes, most of which are unlinked and independent. Many of these genes are polygenic in nature.