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151.
T. ADAK S. K. SUBBARAO V. P. SHARMA S. R. V. RAO 《Medical and veterinary entomology》1994,8(2):137-140
Abstract Genetically controlled enzyme variation exists within and between four sibling species of the Anopheles culicifacies complex of malaria vectors in India. A study on electrophoretic variation of nine enzymes in An.culicifacies sibling species revealed that the lactate dehydrogenase ( Ldh ) locus has Fast (F) and Slow (S) allozymes distinguishing species A+D from species B+C with a probability of c . 95%. 相似文献
152.
The suitability of ensilage as a means of preserving flax was investigated in a series of experiments in which 400 kg round bales of fresh flax were sealed in polyethylene film or plastic wrapped, with or without the addition of formic acid at 2.5 litre t-1 or formalin at 5.6 litre t-1 at the time of baling. Plastic wrapping provided a more effective seal than the bags which were easily punctured by the flax roots resulting in moulding and deterioration of the flax. Where the seal was not broken untreated flax underwent a clostridial fermentation and the pH fell to about 4.8. Cellulolytic activity degraded the flax fibre over a period of 3 to 6 months. The addition of formic acid reduced the cellulolytic activity provided the seal was not broken. In an experiment with 4 kg batches of flax of 65%, 40% or 25% MC sealed in polyethylene film, the addition of formic or propionic acids at 20 g kg-1 DM did not prevent moulding and deterioration, but both NH3 and SO2 at 40 g kg-1 DM preserved the physical structure of the flax. The NH3 darkened the flax and made it pliable and unscutchable while the SO2 bleached it and preserved the fibre without microbiological deterioration. The presence of acids on the moist stored flax appeared to inhibit the progress of normal water retting. 相似文献
153.
Differences in Osmoregulation in Brassica species 总被引:1,自引:0,他引:1
Brassica carinata L (cv Carinata-2) and Brassica napus L (cvHNS-3) were tested for osmoregulation under three sets of environmentsOsmoregulation was found to vary markedly between two species,with the cv Carinata-2 having a greater degree of osmoregulationthan the cv HNS-3 Furthermore, the differences in osmoregulationwere related to leaf diffusive conductance and grain yield inBrassica species Thus, it has potential use as a selection criterionin Brassicas Brassica carinata L, Brassica napus L, osmoregulation, relative water content, leaf water potential, turgor potential, osmotic potential, leaf temperature, leaf diffusive conductance 相似文献
154.
An improved and simple method is described by which serial 10µ frozen sections of plant tissues may be obtained. Thevalue of this method for use in plant histochemistry is discussed. 相似文献
155.
Reversal of ABA-Induced Stomatal Closure by Phenolic Compounds 总被引:10,自引:0,他引:10
Vanillic acid, gallic acid, salicylic acid, cinnamic acid, p-coumaricacid, ferulic acid, coumarin, chlorogenic acid, rutin and morinantagonize the ABA-induced stomatal closure. This suggests thepossibility of a regulatory role of phenolic compounds in thestomatal mechanism. Stomata respond variably to the individualphenolic compound. Some, such as vanillic acid, promote thestomatal opening while others, such as coumarin, inhibit theprocess. Key words: Phenolic compounds, ABA-induced stomatal closure 相似文献
156.
Notes on the ecology of fishes of the genus Aphanius and Gambusia affinis in Southern Iraq 总被引:2,自引:0,他引:2
SUMMARY. The ecology of three commonly occurring cyprinodonts, Aphanius dispar (Ruppell), A. sophiae (Heckel) and A. mento (Heckel) was studied in the Lower Mesopotamian Plain of Iraq. These fishes are chiefly herbivorous, live in the same habitat and generally take the same food, although the dentition of the jaw and pharynx in A. dispar differs from that of A. mento and A. sophiae . The gut contents were mostly filamentous algae. In laboratory experiments all three species ate Gambusia embryos. A. dispar and A. sophiae ate mosquito larvae whereas A. mento did not. All three species were infected with a cestode parasite which prevented development of female ovaries. The behaviour of the three species was different. Both A. dispar and A. sophiae form schools, swimming and feeding together. In their natural habitat, males and females of A. dispar were in separate schools. A. mento did not form schools; the males of this species displayed aggressive behaviour. Some observations were also made on Gambusia affinis (Baird & Girard). 相似文献
157.
158.
SYNOPSIS. Tetratrichomonas gallinarum was found in the blood of 3 chickens experimentally infected with Borrelia anserina . The blood infection was successfully reproduced in healthy chickens and was accompanied by evidence that the trichomonads multiplied in the blood, ingested red blood cells, and were themselves phagocytized by leucocytes. T. gallinarum was maintained in serial passage in chicken embryos as well as in the usual trichomonad culture media. 相似文献
159.
In further studies of soral morphogenesis in common Britishferns, consideration is given to environmental and other factorswhich may be causally involved. Accounts are given of the normalcourse of sporophyll development in Dryopteris austriaca andof the effects of more or less extensive defoliation on theinception of sori in several ferns. Some anomalous developmentsin sporophylls of Blechnum spicant are described and illustrated.Various general ideas regarding factors involved in the onsetof the reproductive phase are discussed. It is concluded that,on the evidence which is admittedly very incomplete, the onsetof the reproductive phase in the fern sporophyte is determinedby the interaction of a number of factors, rather than by thespecial action of some particular factor. Because the nature,functional sorus is a complex and highly organized structure,its further investigation is considered to be a task of veryconsiderable magnitude. 相似文献
160.
The anatomical structure of the naked receptacles of seed-bearingWilliamsonias collected from Amarjola in the Rajmahal Hills,Bihar, is described. The main stele of the receptacle consistsof a large number of poorly developed, inverted, collateral,exarch bundles. In the pedicel portion of the receptacle thereare present double bundle traces of the bracts, while in theupper part of the receptacle there are present isolated, collateral,endarch bundles in the peripheral region of the cortex whichsupply traces to the seminiferous and interseminal scales. Onthe basis of this study it is concluded that the receptacleof Williamsonia is a modified axis of two noded inflorescence. 相似文献