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41.
MonirSIRAJ M. BALAVENKATASUBBAIAH K. CHANDRASEKHARAN B. NATARAJU S. D. SHARMA T. SELVAKUMAR P. SUDHAKARA RAO 《昆虫学报》2007,50(1):74-78
在家蚕疾病中,病毒性疾病是危害茧产品的主要且最普遍的疾病。病毒性蚕软腐病是由BmIFV, BmDNV1 和 BmDNV2引起的。对印度种质库(Indian Germ plasm stock)中的BmDN
V1有抗性和敏感的家蚕品种进行了鉴定。利用标准方法对在BmDNV1感染过程中抗性和敏感品系的主要有机成分的变化(包括总蛋白、碳水化合物和脂类)进行了检测。结果表明: 随着幼虫年龄的增长,对照组和处理组中有机成分(即蛋白质和碳水化合物)的含量也随之增长,但是处理组的增长水平明显地低于各自对照组的增长水平。接种BmDNV1后,与对照组比较,敏感品种体内的血淋巴和中肠组织的总蛋白的量显著地下降。在抗性品种,接种4天后的总蛋白的量有了显著地下降,之后,下降水平小于各自的对照组。在抗性和敏感品种中,血淋巴和中肠组织中的总碳水化合物的量略有下降。在变化不显著的抗性和敏感品种中,血淋巴和中肠组织中的脂质的量有显著地提高。在敏感家蚕品种,生化变化清晰地显示: BmDNV1感染消耗作为主要能量来源的总蛋白和碳水化合物。这些成分的损耗导致了被感染家蚕的生长受阻。 相似文献
42.
SINGH N; SINGH S N; SRIVASTAVA K; YUNUS M; AHMAD K. J; SHARMA S C.; SHARGA A N 《Annals of botany》1990,65(1):41-44
Five Gladiolus cultivars, namely Aldebaran, BrightEye, Illusion, Manisha andManmohan, were exposed to 1 and 2 µg l1sulphur dioxide to test their relative-sensitivity toleranceto the pollutant Plants were fumigated experimentally for 2h daily Foliar injury symptoms were observed first in Manishafollowed by Aldebaran and Illusionat the higher dose Photosynthetic pigments and leaf extractpH were significantly decreased, particularly in Manishaand Illusion Overall disturbances in the plantmetabolism due to SO2 treatment led to retarded growth of plants,as evident from decreased shoot length and phytomass valuesThe order of sensitivity of the five Gladiolus cultivars toSO2 was as follows, with the greatest first Manisha, Illusion,Aldebaran, Bright Eye, Manmohan Cultivars, Gladiolus, sensitivity, sulphur dioxide, tolerance 相似文献
43.
44.
A field experiment was conducted to study the effect of nitrogenapplication at 15, 30 and 45 kg ha1 of urea at pre-flowering(PF) and pod initiation (PI) stages on the activity of nitrogenase(N2ase), nitrate reductase (NR) and other related parametersin the nodules of moong (Vigna radiata). Nitrogen applied atPF or PI stage was found to be inhibitory to N2ase and glutaminesynthetase (GS) activities except at 15 kg N ha1 whenapplied at PF in the case of N2ase. At both the stages therewas increase in NR and glutamate dehydrogenase (GDH) activitieswith the application of nitrogen. Seed yield increased by 18per cent with the application of 15 kg N ha1 at PI stagewhereas nitrogen application at PF stage only increased strawyield significantly. Nitrate reductase, nitrogenase, nitrogen application, ammonia assimilation, Vigna radiata 相似文献
45.
Overcoming Self-incompatibility through the Use of Lectins and Sugars in Petunia and Eruca 总被引:1,自引:0,他引:1
Treatment of stigma with a lectin (Con A/PHA) before pollinationwas effective in overcoming self-incompatibility in Petuniahybrida, a gametophytic self-incompatible system, and Erucasativa, a sporophytic self-incompatible system. Treatment ofpollen with glucose/N-acetyl-D-galactosamine (tested only withPetunia) was also effective. These results suggest the involvementof pollen lectins and specific sugar components of the pistilin self-incompatibility recognition. Petunia hybrida, Eruca sativa, self-incompatibility, pollen recognition, lectins 相似文献
46.
Recent investigations have shown that abscisic acid (ABA) dependsupon the availability of Ca2+ for its action in certain systems.In order to check whether ABA requires Ca2+ to inhibit seedgermination, the effects of ABA, CaCl2, EGTA (a Ca2+ chelator)and lanthanum chloride and nifedipine (Ca2+ channel blockers),individually and in combination, on seed germination of Brassicajuncea L. cv. RLM-198 were studied. ABA inhibited germinationin a concentration dependent manner. ABA-induced inhibitionwas abolished with the lapse of time after application. Calciumneither affected germination nor altered the ABA-induced inhibition.EGTA. La3+ and nifedipine suppressed seed germination when testedindividually and further elevated the ABA effect, in a synergisticway, when applied simultaneously. They also prevented the time-dependentreduction in ABA-induced inhibition. The findings indicate thatCa2+ is not essential for ABA to cause germination inhibition. EGTA, Ca2+ channel blockers, abscisic acid, seed germination, Brassica juncea 相似文献
47.
Papilio demoleus larvae showed maximum attraction to odours of citral, cirtonellal and citronellol, slightly less to geraniol and 1-limonene, and low attraction to hydroxy-citronellal and geranyl acetate. These chemicals (except the last) are the main odorous constituents of the insect's host plant (Citrus) leaves. Phellandrene was almost inert, whereas farnesol and d-limonene elicited a low, and linalool, eugenol and clove oil a high repulsion. Larvae deprived of one antenna and both maxillary palps were similar to normal larvae in their orientational responses. Normal larval responses changed with the inactivation of one or more of the three specific antennal sensilla. A full complement of the three sensilla was not essential for the normal larval response to certain chemicals. Any of the sensilla singly or in combination with any other sensillum could mediate the normal larval response (attraction) to citral and geraniol. For a few other chemicals, certain specific sensilla, singly or in a combination of two, mediated the normal response. Only for d-limonene were all three sensilla essential for the normal response. 相似文献
48.
Shrankhla Preeti SHARMA Lalit MOHAN Chand Narayan SRIVASTAVA 《Entomological Research》2011,41(6):216-220
The larvicidal activity of the plant extracts Pseudocalymma alliaceum and Allium sativum were determined against Culex quinquefasciatus. The hexane extract of P. alliaceum and the petroleum ether extract of A. sativum exhibited larvicidal efficacy against Cx. quinquefasciatus larvae. Extracts of P. alliaceum resulted in concentrations that produced 50% mortality LC50 and LC90 values of 2.49 and 15.06 ppm, respectively, after 24 h and 1.16 and 8.45 ppm after 48 h. Extracts of A. sativum resulted in LC50 and LC90 values of 8.38 and 29.15 ppm after 24 h and 7.28 and 44.19 ppm after 48 h of exposure, respectively. The results indicate that the plant extract component(s) present in the hexane extract of P. alliaceum leaves demonstrated greater potential as an efficient larvicide than A. sativum against Cx. quinquefasciatus. 相似文献
49.
50.
MANMOHAN D. SHARMA TOM TREGENZA DAVID J. HOSKEN 《Biological journal of the Linnean Society. Linnean Society of London》2011,103(4):923-934
There has been recent debate about the expected allometry of sexually‐selected traits. Although sexually‐selected traits exhibit a diversity of allometric patterns, signalling characters are frequently positively allometric. By contrast, insect genitalia tend to be negatively allometric, although the allometry of nongenital sexually‐selected characters in insects is largely unknown (with some notable exceptions). It has also been suggested that there should be a negative association between the asymmetry and size of bilaterally‐paired, sexually‐selected traits, although this claim is controversial. We assessed the allometry and asymmetry (fluctuating asymmetry, FA) of a nongenital contact–courtship structure, the sex comb, in replicate populations of three species of Drosophila (we also measured wing FA). Sex combs are sexually‐selected characters used to grasp the female's abdomen and genitalia and to spread her wings prior to and during copulation. Although species differed in the size of the sex combs, all combs were positively allometric, and comb allometry did not generally differ significantly between species or populations. Comb and wing asymmetry did vary across species, although not across populations of the same species. However, FA was trait specific and was never negatively associated with trait size. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 103 , 923–934. 相似文献