Specificity of Gibberellin and Sucrose-promoted Flower Bud Growth in Gladiolus

A critical stage in flower bud growth in the spike of Gladioluswhich is initiated by gibberellic acid (GA₃) and sustained bysucrose has been identified. This corresponds to the stage atwhich separation of the outer bract occurs. In buds at differentdevelopmental stages isolated and held in water, it is the samebud stage that first shows increased growth. Buds not inducedby light were shown to respond more significantly to GA₃ andsucrose than those induced by light. Since the separation ofthe outer bract results in light-induced amylase productionand starch hydrolysis leading to petal growth, it is proposedthat growth promotion by GA₃ is related to light-induced petalgrowth at this specific stage. flower bud growth, Gladiolus natalensis, gibberellic acid, sucrose     

Diethylphenylacetamide: a new insect repellent against stable fly,Stomoxys calcitrans

Abstract. This paper reports the results of a laboratory study showing effectiveness of a new insect repellent N,N-diethylphenylacetamide (DEPA) against stable fly, Stomoxys calcitrans, and compared to N,N-diethyl-m-toluamide (DEET) and dimethyl-phthalate (DMP). DEPA gave maximum protection time of more than 6h at 3% concentration followed by DEET and DMP.     

The relationships of the Apostasiaceae on the basis of floral anatomy

The Apostasiaceae is a small family of limited distribution, with about 15 species altogether, and its affinities have been controversial. The floral anatomy of nine representatives of the family is now known in detail, and its relationships are discussed on the basis of the floral vasculature. The pattern of the vascular supply to the floral organs is very similar to that of the diandrous orchids, showing the undoubted affinity of the Apostasiaceae with the Orchidaceae. The subtribe Cypripedilinae of the Orchidaceae must have evolved directly from the Apostasiaceae.     

Cytokinins in Gladiolus (Gladiolus grandiflorus) Corms

Ten cytokinin-like substances, termed X₁, X₂, X₃, X_4a, X_4b,X_5a, X_5b, X₆, X₇, and X₈, active in the soya bean hypocotyltest, were detected in gladiolus corms. The factors X_4a, X_5aand X₄ were tentatively identified as zeatin (Z), isopentenyladenosine (iPA) and isopentenyl adenine (iP), respectively,based on their behaviour in Sephadex LH-20 column chromatography,paper chromatography and high pressure liquid chromatography.Factor X₃, which behaved like zeatin riboside (ZR) in the abovesystems could be ZR and/or dihydrozeatin riboside (DHZR). Thebehaviour in Sephadex and ion-exchange column chromatographysuggested that X₁ and X₂ may be cytokinin glucosides and X₅a cytokinin nucleotide or a cytokinin conjugate similar to lupinicacid. The total cytokinin content and the concentration of Z,ZR/DHZR and iPA were higher in non-dormant than in dormant corms.The concentrations of X₁ and X₂ were higher in dormant corms. Gladiolus grandiflorus, gladiolus, dormancy, cytokinins, Sephadex column chromatography, high pressure liquid chromatography     

EFFECT OF BODY SIZE ON THE RESPIRATION OF CERITHIDEA (CERITHIDEOPSILLA) CINGULATA (GMELIN, 1790) AND CERITHIUM CORALIUM KIENER, 1841

The effect of body size on the oxygen consumption and metabolicrate of Cerithidea (Cerithideopsilla) cingulata (Gmelin, 1790)andCerithium coralium Kiener, 1841 was studied at a constant temperatureof 25°C. An exponential relationship has been observed inboth animals. Oxygen consumption showed a positive linear correlationwith a ‘b’ value of 0.6518 in C. cingulata and 0.7667in C. coralium. A negative linear correlation was obtained forthe metabolic rate with a (b-1) value of –0.3482 in C.cingulata and –0.2333 in C. coralium.