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11.
为明确不同寄主和不同信息化合物对豆大蓟马的行为影响,本文应用"Y"型嗅觉仪测定了豆大蓟马雌成虫对两种寄主植物花和不同浓度(v/v)下11种化合物的趋向性反应,结果表明:豆大蓟马对豇豆花、10-4烟酸乙酯、10-6烟酸乙酯、10-2橙花醇、10-2芳樟醇、10-6邻茴香醛和10-23-苯丙醛、10-43-苯丙醛具有极显著的趋向反应;对四季豆花和10-4橙花醇具有显著的趋向反应;10-4β-香茅醇、10-6β-香茅醇和10-6苯甲醛对豆大蓟马具有显著的驱避反应。不同浓度同一化合物对豆大蓟马的吸引作用也存在显著差异。实验结果可为进一步开发利用信息化合物田间防治豆大蓟马提供参考。 相似文献
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Serine protease inhibitors (PIs) have been described in many plant species and are universal throughout the plant kingdom, where trypsin inhibitors is the most common type. In the present study, trypsin and chymotrypsin inhibitory activity was detected in the seed flour extracts of 13 selected cultivars/accessions of cowpea. Two cowpea cultivars, Cream7 and Buff, were found to have higher trypsin and chymotrypsin inhibitory potential compared to other tested cultivars for which they have been selected for further purification studies using ammonium sulfate fractionation and DEAE‐Sephadex A‐25 column. Cream7‐purified proteins showed two bands on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS‐PAGE) corresponding to molecular mass of 17.10 and 14.90 kDa, while the purified protein from Buff cultivar showed a single band corresponding mass of 16.50 kDa. The purified inhibitors were stable at temperature below 60°C and were active at wide range of pH from 2 to 12. The kinetic analysis revealed noncompetitive type of inhibition for both inhibitors against both enzymes. The inhibitor constant (Ki) values suggested high affinity between inhibitors and enzymes. Purified inhibitors were found to have deep and negative effects on the mean larval weight, larval mortality, pupation, and mean pupal weight of Spodoptera littoralis, where Buff PI was more effective than Cream7 PI. It may be concluded that cowpea PI gene(s) could be potential insect control protein for future studies in developing insect‐resistant transgenic plants. 相似文献
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Plants can accumulate, constitutively and/or after induction, a wide variety of defense compounds in their tissues that confer resistance to herbivorous insects. The naturally occurring plant resistance gene pool can serve as an arsenal in pest management via transgenic approaches. As insect‐plant interaction research rapidly advances, it has gradually become clear that the effects of plant defense compounds are determined not only by their toxicity toward target sites, but also by how insects respond to the challenge. Insect digestive tracts are not passive targets of plant defense, but often can adapt to dietary challenge and successfully deal with various plant toxins and anti‐metabolites. This adaptive response has posed an obstacle to biotechnology‐based pest control approaches, which underscores the importance of understanding insect adaptive mechanisms. Molecular studies on the impact of protease inhibitors on insect digestion have contributed significantly to our understanding of insect adaptation to plant defense. This review will focus on exposing how the insect responds to protease inhibitors by both qualitative and quantitative remodeling of their digestive proteases using the cowpea bruchid–soybean cysteine protease inhibitor N system. 相似文献
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B.u.i. Van Le Maria H. Cruz de Carvalho Yasmine Zuily-Fodil Anh T. Pham Thi Kiem Tran Thanh Van 《Journal of plant physiology》2002,159(11)
A simple protocol was established for high frequency direct shoot regeneration of cowpea [Vigna unguiculata (L.) cv. EPACE-1]. Bud proliferation occurred at the cotyledonary nodes of cowpea seedlings three weeks after culture on a medium containing Murashige and Skoog salts (1962) and B5 vitamins (Gamborg et al. 1968) supplemented with TDZ. A 10 μmol/L TDZ pre-treatment, shoot tip removal and excision of longitudinal thin cell layers (TCL) at the level of the cotyledonary nodes with subsequent culture on a MSB5 medium supplemented with 1 μmol/L IBA and 1 μmol/L TDZ were the optimal conditions for maximum bud proliferation. Up to 32.5 regenerated shoot buds were produced per TCL. The regenerated plants (R0) were true-to-type and successfully transferred to soil. 相似文献
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Maria A. G. D. Grazziotin Glaucia B. Cabral Abdulrazak B. Ibrahim Renato B. Machado Francisco J. L. Aragão 《The Annals of applied biology》2020,176(3):268-274
Persistent decrease in the productivity of cowpea (Vigna unguiculata L.) has been partly due to attack by bruchids including Zabrotes subfasciatus and Callosobruchus maculatus. Resistance to these insects in Phaseolus vulgaris L. has been shown to be associated with arcelins, a family of seed proteins encoded by a multigenic family of lectins on the APA locus. In this work, we report the construction of an expression vector containing Arc1 gene isolated from P. vulgaris and introduced into cowpea as a strategy to confer resistance to insect attack. Following transformation and selection, feeding experiments in which C. maculatus and Z. subfasciatus were fed with transgenic (L3 and L5) and non-transgenic (control) grains showed that introduced gene protected the transgenic line. Significant differences (p < .05 and p < .01) were found in the number of eggs laid, the number of emerging insects and the loss of grain mass in L3, compared with control, for both insects. Similar observations were made in L5 with the exception of the number of laid eggs. The strategy here described may form the basis for the development of a cowpea variety tolerant to bruchids in a crop cultivated by farmers throughout Latin America and Africa. 相似文献
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豇豆胰蛋白酶抑制剂基因的克隆 总被引:5,自引:0,他引:5
利用RT-PCR的方法,从豇豆种子,子叶及成熟叶片中分别提取RNA,反转录后以该基因两端的保守序列为引物进行PCR扩增,PCR产物与pUCm-T载体连接进行克隆,蓝白筛选重组子,经测序,其核苷酸同源性高达100%,蛋白质同源性达91%。本试验同时对该基因的表达时期差异进行了大致检测。结果是种子的表达量最高,子叶其次,成熟叶中最低。 相似文献
20.
In trials conducted in Benin, conidia of Beauveria bassiana were evaluated as a control method against the cowpea weevil, Callosobruchus maculatus , in stored cowpea. In the first trial using a high artificial infestation of C. maculatus in 8-kg batches of cowpea in jerry cans under typical conditions, concentrations of 1 × 109 and 1 × 1011 conidia kg−1 were compared with lemon grass oil at 2 mL kg−1 and the synthetic pesticide mixture of 1.5% pirimiphos methyl + 0.05% deltamethrin at 0.5 g kg−1 . After 2 months of storage, seed losses (SD) were 20.63 (5.3)% in the untreated control, 8.04 (3.2)% in the low-dose B. bassiana group, 3.12 (1.3)% in the high-dose B. bassiana group, 2.52 (0.4)% in the lemon grass oil group and 0% in the pirimiphos methyl + deltamethrin group. In a second trial with natural infestations in 50-kg batches of cowpea in 200-L drums, treatment with B. bassiana 1 × 1011 conidia kg−1 was compared with pirimiphos methyl + deltamethrin at 0.5 g kg−1 . After 6 months of storage on six farms, losses reached 30.76 (1.5)% in the control, 1.28 (0.2)% in the pirimiphos methyl + deltamethrin group and 3.69 (0.6)% in the B. bassiana group. 相似文献